1 /* $NetBSD: ip_input.c,v 1.167 2003/06/23 11:02:14 martin Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /*- 33 * Copyright (c) 1998 The NetBSD Foundation, Inc. 34 * All rights reserved. 35 * 36 * This code is derived from software contributed to The NetBSD Foundation 37 * by Public Access Networks Corporation ("Panix"). It was developed under 38 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 3. All advertising materials mentioning features or use of this software 49 * must display the following acknowledgement: 50 * This product includes software developed by the NetBSD 51 * Foundation, Inc. and its contributors. 52 * 4. Neither the name of The NetBSD Foundation nor the names of its 53 * contributors may be used to endorse or promote products derived 54 * from this software without specific prior written permission. 55 * 56 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 57 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 58 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 59 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 60 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 61 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 62 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 63 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 64 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 65 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 66 * POSSIBILITY OF SUCH DAMAGE. 67 */ 68 69 /* 70 * Copyright (c) 1982, 1986, 1988, 1993 71 * The Regents of the University of California. All rights reserved. 72 * 73 * Redistribution and use in source and binary forms, with or without 74 * modification, are permitted provided that the following conditions 75 * are met: 76 * 1. Redistributions of source code must retain the above copyright 77 * notice, this list of conditions and the following disclaimer. 78 * 2. Redistributions in binary form must reproduce the above copyright 79 * notice, this list of conditions and the following disclaimer in the 80 * documentation and/or other materials provided with the distribution. 81 * 3. All advertising materials mentioning features or use of this software 82 * must display the following acknowledgement: 83 * This product includes software developed by the University of 84 * California, Berkeley and its contributors. 85 * 4. Neither the name of the University nor the names of its contributors 86 * may be used to endorse or promote products derived from this software 87 * without specific prior written permission. 88 * 89 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 90 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 91 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 92 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 93 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 94 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 95 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 96 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 97 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 98 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 99 * SUCH DAMAGE. 100 * 101 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 102 */ 103 104 #include <sys/cdefs.h> 105 __KERNEL_RCSID(0, "$NetBSD: ip_input.c,v 1.167 2003/06/23 11:02:14 martin Exp $"); 106 107 #include "opt_gateway.h" 108 #include "opt_pfil_hooks.h" 109 #include "opt_ipsec.h" 110 #include "opt_mrouting.h" 111 #include "opt_mbuftrace.h" 112 #include "opt_inet_csum.h" 113 114 #include <sys/param.h> 115 #include <sys/systm.h> 116 #include <sys/malloc.h> 117 #include <sys/mbuf.h> 118 #include <sys/domain.h> 119 #include <sys/protosw.h> 120 #include <sys/socket.h> 121 #include <sys/socketvar.h> 122 #include <sys/errno.h> 123 #include <sys/time.h> 124 #include <sys/kernel.h> 125 #include <sys/pool.h> 126 #include <sys/sysctl.h> 127 128 #include <net/if.h> 129 #include <net/if_dl.h> 130 #include <net/route.h> 131 #include <net/pfil.h> 132 133 #include <netinet/in.h> 134 #include <netinet/in_systm.h> 135 #include <netinet/ip.h> 136 #include <netinet/in_pcb.h> 137 #include <netinet/in_var.h> 138 #include <netinet/ip_var.h> 139 #include <netinet/ip_icmp.h> 140 /* just for gif_ttl */ 141 #include <netinet/in_gif.h> 142 #include "gif.h" 143 #include <net/if_gre.h> 144 #include "gre.h" 145 146 #ifdef MROUTING 147 #include <netinet/ip_mroute.h> 148 #endif 149 150 #ifdef IPSEC 151 #include <netinet6/ipsec.h> 152 #include <netkey/key.h> 153 #endif 154 155 #ifndef IPFORWARDING 156 #ifdef GATEWAY 157 #define IPFORWARDING 1 /* forward IP packets not for us */ 158 #else /* GATEWAY */ 159 #define IPFORWARDING 0 /* don't forward IP packets not for us */ 160 #endif /* GATEWAY */ 161 #endif /* IPFORWARDING */ 162 #ifndef IPSENDREDIRECTS 163 #define IPSENDREDIRECTS 1 164 #endif 165 #ifndef IPFORWSRCRT 166 #define IPFORWSRCRT 1 /* forward source-routed packets */ 167 #endif 168 #ifndef IPALLOWSRCRT 169 #define IPALLOWSRCRT 1 /* allow source-routed packets */ 170 #endif 171 #ifndef IPMTUDISC 172 #define IPMTUDISC 1 173 #endif 174 #ifndef IPMTUDISCTIMEOUT 175 #define IPMTUDISCTIMEOUT (10 * 60) /* as per RFC 1191 */ 176 #endif 177 178 /* 179 * Note: DIRECTED_BROADCAST is handled this way so that previous 180 * configuration using this option will Just Work. 181 */ 182 #ifndef IPDIRECTEDBCAST 183 #ifdef DIRECTED_BROADCAST 184 #define IPDIRECTEDBCAST 1 185 #else 186 #define IPDIRECTEDBCAST 0 187 #endif /* DIRECTED_BROADCAST */ 188 #endif /* IPDIRECTEDBCAST */ 189 int ipforwarding = IPFORWARDING; 190 int ipsendredirects = IPSENDREDIRECTS; 191 int ip_defttl = IPDEFTTL; 192 int ip_forwsrcrt = IPFORWSRCRT; 193 int ip_directedbcast = IPDIRECTEDBCAST; 194 int ip_allowsrcrt = IPALLOWSRCRT; 195 int ip_mtudisc = IPMTUDISC; 196 int ip_mtudisc_timeout = IPMTUDISCTIMEOUT; 197 #ifdef DIAGNOSTIC 198 int ipprintfs = 0; 199 #endif 200 /* 201 * XXX - Setting ip_checkinterface mostly implements the receive side of 202 * the Strong ES model described in RFC 1122, but since the routing table 203 * and transmit implementation do not implement the Strong ES model, 204 * setting this to 1 results in an odd hybrid. 205 * 206 * XXX - ip_checkinterface currently must be disabled if you use ipnat 207 * to translate the destination address to another local interface. 208 * 209 * XXX - ip_checkinterface must be disabled if you add IP aliases 210 * to the loopback interface instead of the interface where the 211 * packets for those addresses are received. 212 */ 213 int ip_checkinterface = 0; 214 215 216 struct rttimer_queue *ip_mtudisc_timeout_q = NULL; 217 218 extern struct domain inetdomain; 219 int ipqmaxlen = IFQ_MAXLEN; 220 u_long in_ifaddrhash; /* size of hash table - 1 */ 221 int in_ifaddrentries; /* total number of addrs */ 222 struct in_ifaddrhead in_ifaddr; 223 struct in_ifaddrhashhead *in_ifaddrhashtbl; 224 u_long in_multihash; /* size of hash table - 1 */ 225 int in_multientries; /* total number of addrs */ 226 struct in_multihead in_multi; 227 struct in_multihashhead *in_multihashtbl; 228 struct ifqueue ipintrq; 229 struct ipstat ipstat; 230 u_int16_t ip_id; 231 232 #ifdef PFIL_HOOKS 233 struct pfil_head inet_pfil_hook; 234 #endif 235 236 struct ipqhead ipq; 237 int ipq_locked; 238 int ip_nfragpackets = 0; 239 int ip_maxfragpackets = 200; 240 241 static __inline int ipq_lock_try __P((void)); 242 static __inline void ipq_unlock __P((void)); 243 244 static __inline int 245 ipq_lock_try() 246 { 247 int s; 248 249 /* 250 * Use splvm() -- we're blocking things that would cause 251 * mbuf allocation. 252 */ 253 s = splvm(); 254 if (ipq_locked) { 255 splx(s); 256 return (0); 257 } 258 ipq_locked = 1; 259 splx(s); 260 return (1); 261 } 262 263 static __inline void 264 ipq_unlock() 265 { 266 int s; 267 268 s = splvm(); 269 ipq_locked = 0; 270 splx(s); 271 } 272 273 #ifdef DIAGNOSTIC 274 #define IPQ_LOCK() \ 275 do { \ 276 if (ipq_lock_try() == 0) { \ 277 printf("%s:%d: ipq already locked\n", __FILE__, __LINE__); \ 278 panic("ipq_lock"); \ 279 } \ 280 } while (/*CONSTCOND*/ 0) 281 #define IPQ_LOCK_CHECK() \ 282 do { \ 283 if (ipq_locked == 0) { \ 284 printf("%s:%d: ipq lock not held\n", __FILE__, __LINE__); \ 285 panic("ipq lock check"); \ 286 } \ 287 } while (/*CONSTCOND*/ 0) 288 #else 289 #define IPQ_LOCK() (void) ipq_lock_try() 290 #define IPQ_LOCK_CHECK() /* nothing */ 291 #endif 292 293 #define IPQ_UNLOCK() ipq_unlock() 294 295 struct pool inmulti_pool; 296 struct pool ipqent_pool; 297 298 #ifdef INET_CSUM_COUNTERS 299 #include <sys/device.h> 300 301 struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 302 NULL, "inet", "hwcsum bad"); 303 struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 304 NULL, "inet", "hwcsum ok"); 305 struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 306 NULL, "inet", "swcsum"); 307 308 #define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++ 309 310 #else 311 312 #define INET_CSUM_COUNTER_INCR(ev) /* nothing */ 313 314 #endif /* INET_CSUM_COUNTERS */ 315 316 /* 317 * We need to save the IP options in case a protocol wants to respond 318 * to an incoming packet over the same route if the packet got here 319 * using IP source routing. This allows connection establishment and 320 * maintenance when the remote end is on a network that is not known 321 * to us. 322 */ 323 int ip_nhops = 0; 324 static struct ip_srcrt { 325 struct in_addr dst; /* final destination */ 326 char nop; /* one NOP to align */ 327 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */ 328 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)]; 329 } ip_srcrt; 330 331 static void save_rte __P((u_char *, struct in_addr)); 332 333 #ifdef MBUFTRACE 334 struct mowner ip_rx_mowner = { "internet", "rx" }; 335 struct mowner ip_tx_mowner = { "internet", "tx" }; 336 #endif 337 338 /* 339 * IP initialization: fill in IP protocol switch table. 340 * All protocols not implemented in kernel go to raw IP protocol handler. 341 */ 342 void 343 ip_init() 344 { 345 struct protosw *pr; 346 int i; 347 348 pool_init(&inmulti_pool, sizeof(struct in_multi), 0, 0, 0, "inmltpl", 349 NULL); 350 pool_init(&ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl", 351 NULL); 352 353 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); 354 if (pr == 0) 355 panic("ip_init"); 356 for (i = 0; i < IPPROTO_MAX; i++) 357 ip_protox[i] = pr - inetsw; 358 for (pr = inetdomain.dom_protosw; 359 pr < inetdomain.dom_protoswNPROTOSW; pr++) 360 if (pr->pr_domain->dom_family == PF_INET && 361 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 362 ip_protox[pr->pr_protocol] = pr - inetsw; 363 LIST_INIT(&ipq); 364 ip_id = time.tv_sec & 0xffff; 365 ipintrq.ifq_maxlen = ipqmaxlen; 366 TAILQ_INIT(&in_ifaddr); 367 in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IFADDR, 368 M_WAITOK, &in_ifaddrhash); 369 in_multihashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IPMADDR, 370 M_WAITOK, &in_multihash); 371 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout); 372 #ifdef GATEWAY 373 ipflow_init(); 374 #endif 375 376 #ifdef PFIL_HOOKS 377 /* Register our Packet Filter hook. */ 378 inet_pfil_hook.ph_type = PFIL_TYPE_AF; 379 inet_pfil_hook.ph_af = AF_INET; 380 i = pfil_head_register(&inet_pfil_hook); 381 if (i != 0) 382 printf("ip_init: WARNING: unable to register pfil hook, " 383 "error %d\n", i); 384 #endif /* PFIL_HOOKS */ 385 386 #ifdef INET_CSUM_COUNTERS 387 evcnt_attach_static(&ip_hwcsum_bad); 388 evcnt_attach_static(&ip_hwcsum_ok); 389 evcnt_attach_static(&ip_swcsum); 390 #endif /* INET_CSUM_COUNTERS */ 391 392 #ifdef MBUFTRACE 393 MOWNER_ATTACH(&ip_tx_mowner); 394 MOWNER_ATTACH(&ip_rx_mowner); 395 #endif /* MBUFTRACE */ 396 } 397 398 struct sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET }; 399 struct route ipforward_rt; 400 401 /* 402 * IP software interrupt routine 403 */ 404 void 405 ipintr() 406 { 407 int s; 408 struct mbuf *m; 409 410 while (1) { 411 s = splnet(); 412 IF_DEQUEUE(&ipintrq, m); 413 splx(s); 414 if (m == 0) 415 return; 416 MCLAIM(m, &ip_rx_mowner); 417 ip_input(m); 418 } 419 } 420 421 /* 422 * Ip input routine. Checksum and byte swap header. If fragmented 423 * try to reassemble. Process options. Pass to next level. 424 */ 425 void 426 ip_input(struct mbuf *m) 427 { 428 struct ip *ip = NULL; 429 struct ipq *fp; 430 struct in_ifaddr *ia; 431 struct ifaddr *ifa; 432 struct ipqent *ipqe; 433 int hlen = 0, mff, len; 434 int downmatch; 435 int checkif; 436 437 MCLAIM(m, &ip_rx_mowner); 438 #ifdef DIAGNOSTIC 439 if ((m->m_flags & M_PKTHDR) == 0) 440 panic("ipintr no HDR"); 441 #endif 442 #ifdef IPSEC 443 /* 444 * should the inner packet be considered authentic? 445 * see comment in ah4_input(). 446 */ 447 if (m) { 448 m->m_flags &= ~M_AUTHIPHDR; 449 m->m_flags &= ~M_AUTHIPDGM; 450 } 451 #endif 452 453 /* 454 * If no IP addresses have been set yet but the interfaces 455 * are receiving, can't do anything with incoming packets yet. 456 */ 457 if (TAILQ_FIRST(&in_ifaddr) == 0) 458 goto bad; 459 ipstat.ips_total++; 460 /* 461 * If the IP header is not aligned, slurp it up into a new 462 * mbuf with space for link headers, in the event we forward 463 * it. Otherwise, if it is aligned, make sure the entire 464 * base IP header is in the first mbuf of the chain. 465 */ 466 if (IP_HDR_ALIGNED_P(mtod(m, caddr_t)) == 0) { 467 if ((m = m_copyup(m, sizeof(struct ip), 468 (max_linkhdr + 3) & ~3)) == NULL) { 469 /* XXXJRT new stat, please */ 470 ipstat.ips_toosmall++; 471 return; 472 } 473 } else if (__predict_false(m->m_len < sizeof (struct ip))) { 474 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) { 475 ipstat.ips_toosmall++; 476 return; 477 } 478 } 479 ip = mtod(m, struct ip *); 480 if (ip->ip_v != IPVERSION) { 481 ipstat.ips_badvers++; 482 goto bad; 483 } 484 hlen = ip->ip_hl << 2; 485 if (hlen < sizeof(struct ip)) { /* minimum header length */ 486 ipstat.ips_badhlen++; 487 goto bad; 488 } 489 if (hlen > m->m_len) { 490 if ((m = m_pullup(m, hlen)) == 0) { 491 ipstat.ips_badhlen++; 492 return; 493 } 494 ip = mtod(m, struct ip *); 495 } 496 497 /* 498 * RFC1122: packets with a multicast source address are 499 * not allowed. 500 */ 501 if (IN_MULTICAST(ip->ip_src.s_addr)) { 502 ipstat.ips_badaddr++; 503 goto bad; 504 } 505 506 /* 127/8 must not appear on wire - RFC1122 */ 507 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 508 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 509 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 510 ipstat.ips_badaddr++; 511 goto bad; 512 } 513 } 514 515 switch (m->m_pkthdr.csum_flags & 516 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) | 517 M_CSUM_IPv4_BAD)) { 518 case M_CSUM_IPv4|M_CSUM_IPv4_BAD: 519 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad); 520 goto badcsum; 521 522 case M_CSUM_IPv4: 523 /* Checksum was okay. */ 524 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok); 525 break; 526 527 default: 528 /* Must compute it ourselves. */ 529 INET_CSUM_COUNTER_INCR(&ip_swcsum); 530 if (in_cksum(m, hlen) != 0) 531 goto bad; 532 break; 533 } 534 535 /* Retrieve the packet length. */ 536 len = ntohs(ip->ip_len); 537 538 /* 539 * Check for additional length bogosity 540 */ 541 if (len < hlen) { 542 ipstat.ips_badlen++; 543 goto bad; 544 } 545 546 /* 547 * Check that the amount of data in the buffers 548 * is as at least much as the IP header would have us expect. 549 * Trim mbufs if longer than we expect. 550 * Drop packet if shorter than we expect. 551 */ 552 if (m->m_pkthdr.len < len) { 553 ipstat.ips_tooshort++; 554 goto bad; 555 } 556 if (m->m_pkthdr.len > len) { 557 if (m->m_len == m->m_pkthdr.len) { 558 m->m_len = len; 559 m->m_pkthdr.len = len; 560 } else 561 m_adj(m, len - m->m_pkthdr.len); 562 } 563 564 #ifdef IPSEC 565 /* ipflow (IP fast forwarding) is not compatible with IPsec. */ 566 m->m_flags &= ~M_CANFASTFWD; 567 #else 568 /* 569 * Assume that we can create a fast-forward IP flow entry 570 * based on this packet. 571 */ 572 m->m_flags |= M_CANFASTFWD; 573 #endif 574 575 #ifdef PFIL_HOOKS 576 /* 577 * Run through list of hooks for input packets. If there are any 578 * filters which require that additional packets in the flow are 579 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 580 * Note that filters must _never_ set this flag, as another filter 581 * in the list may have previously cleared it. 582 */ 583 /* 584 * let ipfilter look at packet on the wire, 585 * not the decapsulated packet. 586 */ 587 #ifdef IPSEC 588 if (!ipsec_getnhist(m)) 589 #else 590 if (1) 591 #endif 592 { 593 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif, 594 PFIL_IN) != 0) 595 return; 596 if (m == NULL) 597 return; 598 ip = mtod(m, struct ip *); 599 hlen = ip->ip_hl << 2; 600 } 601 #endif /* PFIL_HOOKS */ 602 603 #ifdef ALTQ 604 /* XXX Temporary until ALTQ is changed to use a pfil hook */ 605 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) { 606 /* packet dropped by traffic conditioner */ 607 return; 608 } 609 #endif 610 611 /* 612 * Process options and, if not destined for us, 613 * ship it on. ip_dooptions returns 1 when an 614 * error was detected (causing an icmp message 615 * to be sent and the original packet to be freed). 616 */ 617 ip_nhops = 0; /* for source routed packets */ 618 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 619 return; 620 621 /* 622 * Enable a consistency check between the destination address 623 * and the arrival interface for a unicast packet (the RFC 1122 624 * strong ES model) if IP forwarding is disabled and the packet 625 * is not locally generated. 626 * 627 * XXX - Checking also should be disabled if the destination 628 * address is ipnat'ed to a different interface. 629 * 630 * XXX - Checking is incompatible with IP aliases added 631 * to the loopback interface instead of the interface where 632 * the packets are received. 633 * 634 * XXX - We need to add a per ifaddr flag for this so that 635 * we get finer grain control. 636 */ 637 checkif = ip_checkinterface && (ipforwarding == 0) && 638 (m->m_pkthdr.rcvif != NULL) && 639 ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0); 640 641 /* 642 * Check our list of addresses, to see if the packet is for us. 643 * 644 * Traditional 4.4BSD did not consult IFF_UP at all. 645 * The behavior here is to treat addresses on !IFF_UP interface 646 * as not mine. 647 */ 648 downmatch = 0; 649 LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) { 650 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) { 651 if (checkif && ia->ia_ifp != m->m_pkthdr.rcvif) 652 continue; 653 if ((ia->ia_ifp->if_flags & IFF_UP) != 0) 654 break; 655 else 656 downmatch++; 657 } 658 } 659 if (ia != NULL) 660 goto ours; 661 if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 662 TAILQ_FOREACH(ifa, &m->m_pkthdr.rcvif->if_addrlist, ifa_list) { 663 if (ifa->ifa_addr->sa_family != AF_INET) 664 continue; 665 ia = ifatoia(ifa); 666 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 667 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 668 /* 669 * Look for all-0's host part (old broadcast addr), 670 * either for subnet or net. 671 */ 672 ip->ip_dst.s_addr == ia->ia_subnet || 673 ip->ip_dst.s_addr == ia->ia_net) 674 goto ours; 675 /* 676 * An interface with IP address zero accepts 677 * all packets that arrive on that interface. 678 */ 679 if (in_nullhost(ia->ia_addr.sin_addr)) 680 goto ours; 681 } 682 } 683 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 684 struct in_multi *inm; 685 #ifdef MROUTING 686 extern struct socket *ip_mrouter; 687 688 if (M_READONLY(m)) { 689 if ((m = m_pullup(m, hlen)) == 0) { 690 ipstat.ips_toosmall++; 691 return; 692 } 693 ip = mtod(m, struct ip *); 694 } 695 696 if (ip_mrouter) { 697 /* 698 * If we are acting as a multicast router, all 699 * incoming multicast packets are passed to the 700 * kernel-level multicast forwarding function. 701 * The packet is returned (relatively) intact; if 702 * ip_mforward() returns a non-zero value, the packet 703 * must be discarded, else it may be accepted below. 704 * 705 * (The IP ident field is put in the same byte order 706 * as expected when ip_mforward() is called from 707 * ip_output().) 708 */ 709 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 710 ipstat.ips_cantforward++; 711 m_freem(m); 712 return; 713 } 714 715 /* 716 * The process-level routing demon needs to receive 717 * all multicast IGMP packets, whether or not this 718 * host belongs to their destination groups. 719 */ 720 if (ip->ip_p == IPPROTO_IGMP) 721 goto ours; 722 ipstat.ips_forward++; 723 } 724 #endif 725 /* 726 * See if we belong to the destination multicast group on the 727 * arrival interface. 728 */ 729 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 730 if (inm == NULL) { 731 ipstat.ips_cantforward++; 732 m_freem(m); 733 return; 734 } 735 goto ours; 736 } 737 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 738 in_nullhost(ip->ip_dst)) 739 goto ours; 740 741 /* 742 * Not for us; forward if possible and desirable. 743 */ 744 if (ipforwarding == 0) { 745 ipstat.ips_cantforward++; 746 m_freem(m); 747 } else { 748 /* 749 * If ip_dst matched any of my address on !IFF_UP interface, 750 * and there's no IFF_UP interface that matches ip_dst, 751 * send icmp unreach. Forwarding it will result in in-kernel 752 * forwarding loop till TTL goes to 0. 753 */ 754 if (downmatch) { 755 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0); 756 ipstat.ips_cantforward++; 757 return; 758 } 759 #ifdef IPSEC 760 if (ipsec4_in_reject(m, NULL)) { 761 ipsecstat.in_polvio++; 762 goto bad; 763 } 764 #endif 765 766 ip_forward(m, 0); 767 } 768 return; 769 770 ours: 771 /* 772 * If offset or IP_MF are set, must reassemble. 773 * Otherwise, nothing need be done. 774 * (We could look in the reassembly queue to see 775 * if the packet was previously fragmented, 776 * but it's not worth the time; just let them time out.) 777 */ 778 if (ip->ip_off & ~htons(IP_DF|IP_RF)) { 779 if (M_READONLY(m)) { 780 if ((m = m_pullup(m, hlen)) == NULL) { 781 ipstat.ips_toosmall++; 782 goto bad; 783 } 784 ip = mtod(m, struct ip *); 785 } 786 787 /* 788 * Look for queue of fragments 789 * of this datagram. 790 */ 791 IPQ_LOCK(); 792 LIST_FOREACH(fp, &ipq, ipq_q) 793 if (ip->ip_id == fp->ipq_id && 794 in_hosteq(ip->ip_src, fp->ipq_src) && 795 in_hosteq(ip->ip_dst, fp->ipq_dst) && 796 ip->ip_p == fp->ipq_p) 797 goto found; 798 fp = 0; 799 found: 800 801 /* 802 * Adjust ip_len to not reflect header, 803 * set ipqe_mff if more fragments are expected, 804 * convert offset of this to bytes. 805 */ 806 ip->ip_len = htons(ntohs(ip->ip_len) - hlen); 807 mff = (ip->ip_off & htons(IP_MF)) != 0; 808 if (mff) { 809 /* 810 * Make sure that fragments have a data length 811 * that's a non-zero multiple of 8 bytes. 812 */ 813 if (ntohs(ip->ip_len) == 0 || 814 (ntohs(ip->ip_len) & 0x7) != 0) { 815 ipstat.ips_badfrags++; 816 IPQ_UNLOCK(); 817 goto bad; 818 } 819 } 820 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3); 821 822 /* 823 * If datagram marked as having more fragments 824 * or if this is not the first fragment, 825 * attempt reassembly; if it succeeds, proceed. 826 */ 827 if (mff || ip->ip_off != htons(0)) { 828 ipstat.ips_fragments++; 829 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 830 if (ipqe == NULL) { 831 ipstat.ips_rcvmemdrop++; 832 IPQ_UNLOCK(); 833 goto bad; 834 } 835 ipqe->ipqe_mff = mff; 836 ipqe->ipqe_m = m; 837 ipqe->ipqe_ip = ip; 838 m = ip_reass(ipqe, fp); 839 if (m == 0) { 840 IPQ_UNLOCK(); 841 return; 842 } 843 ipstat.ips_reassembled++; 844 ip = mtod(m, struct ip *); 845 hlen = ip->ip_hl << 2; 846 ip->ip_len = htons(ntohs(ip->ip_len) + hlen); 847 } else 848 if (fp) 849 ip_freef(fp); 850 IPQ_UNLOCK(); 851 } 852 853 #ifdef IPSEC 854 /* 855 * enforce IPsec policy checking if we are seeing last header. 856 * note that we do not visit this with protocols with pcb layer 857 * code - like udp/tcp/raw ip. 858 */ 859 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 && 860 ipsec4_in_reject(m, NULL)) { 861 ipsecstat.in_polvio++; 862 goto bad; 863 } 864 #endif 865 866 /* 867 * Switch out to protocol's input routine. 868 */ 869 #if IFA_STATS 870 if (ia && ip) 871 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len); 872 #endif 873 ipstat.ips_delivered++; 874 { 875 int off = hlen, nh = ip->ip_p; 876 877 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh); 878 return; 879 } 880 bad: 881 m_freem(m); 882 return; 883 884 badcsum: 885 ipstat.ips_badsum++; 886 m_freem(m); 887 } 888 889 /* 890 * Take incoming datagram fragment and try to 891 * reassemble it into whole datagram. If a chain for 892 * reassembly of this datagram already exists, then it 893 * is given as fp; otherwise have to make a chain. 894 */ 895 struct mbuf * 896 ip_reass(ipqe, fp) 897 struct ipqent *ipqe; 898 struct ipq *fp; 899 { 900 struct mbuf *m = ipqe->ipqe_m; 901 struct ipqent *nq, *p, *q; 902 struct ip *ip; 903 struct mbuf *t; 904 int hlen = ipqe->ipqe_ip->ip_hl << 2; 905 int i, next; 906 907 IPQ_LOCK_CHECK(); 908 909 /* 910 * Presence of header sizes in mbufs 911 * would confuse code below. 912 */ 913 m->m_data += hlen; 914 m->m_len -= hlen; 915 916 /* 917 * If first fragment to arrive, create a reassembly queue. 918 */ 919 if (fp == 0) { 920 /* 921 * Enforce upper bound on number of fragmented packets 922 * for which we attempt reassembly; 923 * If maxfrag is 0, never accept fragments. 924 * If maxfrag is -1, accept all fragments without limitation. 925 */ 926 if (ip_maxfragpackets < 0) 927 ; 928 else if (ip_nfragpackets >= ip_maxfragpackets) 929 goto dropfrag; 930 ip_nfragpackets++; 931 MALLOC(fp, struct ipq *, sizeof (struct ipq), 932 M_FTABLE, M_NOWAIT); 933 if (fp == NULL) 934 goto dropfrag; 935 LIST_INSERT_HEAD(&ipq, fp, ipq_q); 936 fp->ipq_ttl = IPFRAGTTL; 937 fp->ipq_p = ipqe->ipqe_ip->ip_p; 938 fp->ipq_id = ipqe->ipqe_ip->ip_id; 939 TAILQ_INIT(&fp->ipq_fragq); 940 fp->ipq_src = ipqe->ipqe_ip->ip_src; 941 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 942 p = NULL; 943 goto insert; 944 } 945 946 /* 947 * Find a segment which begins after this one does. 948 */ 949 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 950 p = q, q = TAILQ_NEXT(q, ipqe_q)) 951 if (ntohs(q->ipqe_ip->ip_off) > ntohs(ipqe->ipqe_ip->ip_off)) 952 break; 953 954 /* 955 * If there is a preceding segment, it may provide some of 956 * our data already. If so, drop the data from the incoming 957 * segment. If it provides all of our data, drop us. 958 */ 959 if (p != NULL) { 960 i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) - 961 ntohs(ipqe->ipqe_ip->ip_off); 962 if (i > 0) { 963 if (i >= ntohs(ipqe->ipqe_ip->ip_len)) 964 goto dropfrag; 965 m_adj(ipqe->ipqe_m, i); 966 ipqe->ipqe_ip->ip_off = 967 htons(ntohs(ipqe->ipqe_ip->ip_off) + i); 968 ipqe->ipqe_ip->ip_len = 969 htons(ntohs(ipqe->ipqe_ip->ip_len) - i); 970 } 971 } 972 973 /* 974 * While we overlap succeeding segments trim them or, 975 * if they are completely covered, dequeue them. 976 */ 977 for (; q != NULL && 978 ntohs(ipqe->ipqe_ip->ip_off) + ntohs(ipqe->ipqe_ip->ip_len) > 979 ntohs(q->ipqe_ip->ip_off); q = nq) { 980 i = (ntohs(ipqe->ipqe_ip->ip_off) + 981 ntohs(ipqe->ipqe_ip->ip_len)) - ntohs(q->ipqe_ip->ip_off); 982 if (i < ntohs(q->ipqe_ip->ip_len)) { 983 q->ipqe_ip->ip_len = 984 htons(ntohs(q->ipqe_ip->ip_len) - i); 985 q->ipqe_ip->ip_off = 986 htons(ntohs(q->ipqe_ip->ip_off) + i); 987 m_adj(q->ipqe_m, i); 988 break; 989 } 990 nq = TAILQ_NEXT(q, ipqe_q); 991 m_freem(q->ipqe_m); 992 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 993 pool_put(&ipqent_pool, q); 994 } 995 996 insert: 997 /* 998 * Stick new segment in its place; 999 * check for complete reassembly. 1000 */ 1001 if (p == NULL) { 1002 TAILQ_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 1003 } else { 1004 TAILQ_INSERT_AFTER(&fp->ipq_fragq, p, ipqe, ipqe_q); 1005 } 1006 next = 0; 1007 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1008 p = q, q = TAILQ_NEXT(q, ipqe_q)) { 1009 if (ntohs(q->ipqe_ip->ip_off) != next) 1010 return (0); 1011 next += ntohs(q->ipqe_ip->ip_len); 1012 } 1013 if (p->ipqe_mff) 1014 return (0); 1015 1016 /* 1017 * Reassembly is complete. Check for a bogus message size and 1018 * concatenate fragments. 1019 */ 1020 q = TAILQ_FIRST(&fp->ipq_fragq); 1021 ip = q->ipqe_ip; 1022 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 1023 ipstat.ips_toolong++; 1024 ip_freef(fp); 1025 return (0); 1026 } 1027 m = q->ipqe_m; 1028 t = m->m_next; 1029 m->m_next = 0; 1030 m_cat(m, t); 1031 nq = TAILQ_NEXT(q, ipqe_q); 1032 pool_put(&ipqent_pool, q); 1033 for (q = nq; q != NULL; q = nq) { 1034 t = q->ipqe_m; 1035 nq = TAILQ_NEXT(q, ipqe_q); 1036 pool_put(&ipqent_pool, q); 1037 m_cat(m, t); 1038 } 1039 1040 /* 1041 * Create header for new ip packet by 1042 * modifying header of first packet; 1043 * dequeue and discard fragment reassembly header. 1044 * Make header visible. 1045 */ 1046 ip->ip_len = htons(next); 1047 ip->ip_src = fp->ipq_src; 1048 ip->ip_dst = fp->ipq_dst; 1049 LIST_REMOVE(fp, ipq_q); 1050 FREE(fp, M_FTABLE); 1051 ip_nfragpackets--; 1052 m->m_len += (ip->ip_hl << 2); 1053 m->m_data -= (ip->ip_hl << 2); 1054 /* some debugging cruft by sklower, below, will go away soon */ 1055 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 1056 int plen = 0; 1057 for (t = m; t; t = t->m_next) 1058 plen += t->m_len; 1059 m->m_pkthdr.len = plen; 1060 } 1061 return (m); 1062 1063 dropfrag: 1064 ipstat.ips_fragdropped++; 1065 m_freem(m); 1066 pool_put(&ipqent_pool, ipqe); 1067 return (0); 1068 } 1069 1070 /* 1071 * Free a fragment reassembly header and all 1072 * associated datagrams. 1073 */ 1074 void 1075 ip_freef(fp) 1076 struct ipq *fp; 1077 { 1078 struct ipqent *q, *p; 1079 1080 IPQ_LOCK_CHECK(); 1081 1082 for (q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; q = p) { 1083 p = TAILQ_NEXT(q, ipqe_q); 1084 m_freem(q->ipqe_m); 1085 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1086 pool_put(&ipqent_pool, q); 1087 } 1088 LIST_REMOVE(fp, ipq_q); 1089 FREE(fp, M_FTABLE); 1090 ip_nfragpackets--; 1091 } 1092 1093 /* 1094 * IP timer processing; 1095 * if a timer expires on a reassembly 1096 * queue, discard it. 1097 */ 1098 void 1099 ip_slowtimo() 1100 { 1101 struct ipq *fp, *nfp; 1102 int s = splsoftnet(); 1103 1104 IPQ_LOCK(); 1105 for (fp = LIST_FIRST(&ipq); fp != NULL; fp = nfp) { 1106 nfp = LIST_NEXT(fp, ipq_q); 1107 if (--fp->ipq_ttl == 0) { 1108 ipstat.ips_fragtimeout++; 1109 ip_freef(fp); 1110 } 1111 } 1112 /* 1113 * If we are over the maximum number of fragments 1114 * (due to the limit being lowered), drain off 1115 * enough to get down to the new limit. 1116 */ 1117 if (ip_maxfragpackets < 0) 1118 ; 1119 else { 1120 while (ip_nfragpackets > ip_maxfragpackets && LIST_FIRST(&ipq)) 1121 ip_freef(LIST_FIRST(&ipq)); 1122 } 1123 IPQ_UNLOCK(); 1124 #ifdef GATEWAY 1125 ipflow_slowtimo(); 1126 #endif 1127 splx(s); 1128 } 1129 1130 /* 1131 * Drain off all datagram fragments. 1132 */ 1133 void 1134 ip_drain() 1135 { 1136 1137 /* 1138 * We may be called from a device's interrupt context. If 1139 * the ipq is already busy, just bail out now. 1140 */ 1141 if (ipq_lock_try() == 0) 1142 return; 1143 1144 while (LIST_FIRST(&ipq) != NULL) { 1145 ipstat.ips_fragdropped++; 1146 ip_freef(LIST_FIRST(&ipq)); 1147 } 1148 1149 IPQ_UNLOCK(); 1150 } 1151 1152 /* 1153 * Do option processing on a datagram, 1154 * possibly discarding it if bad options are encountered, 1155 * or forwarding it if source-routed. 1156 * Returns 1 if packet has been forwarded/freed, 1157 * 0 if the packet should be processed further. 1158 */ 1159 int 1160 ip_dooptions(m) 1161 struct mbuf *m; 1162 { 1163 struct ip *ip = mtod(m, struct ip *); 1164 u_char *cp, *cp0; 1165 struct ip_timestamp *ipt; 1166 struct in_ifaddr *ia; 1167 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 1168 struct in_addr dst; 1169 n_time ntime; 1170 1171 dst = ip->ip_dst; 1172 cp = (u_char *)(ip + 1); 1173 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1174 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1175 opt = cp[IPOPT_OPTVAL]; 1176 if (opt == IPOPT_EOL) 1177 break; 1178 if (opt == IPOPT_NOP) 1179 optlen = 1; 1180 else { 1181 if (cnt < IPOPT_OLEN + sizeof(*cp)) { 1182 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1183 goto bad; 1184 } 1185 optlen = cp[IPOPT_OLEN]; 1186 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) { 1187 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1188 goto bad; 1189 } 1190 } 1191 switch (opt) { 1192 1193 default: 1194 break; 1195 1196 /* 1197 * Source routing with record. 1198 * Find interface with current destination address. 1199 * If none on this machine then drop if strictly routed, 1200 * or do nothing if loosely routed. 1201 * Record interface address and bring up next address 1202 * component. If strictly routed make sure next 1203 * address is on directly accessible net. 1204 */ 1205 case IPOPT_LSRR: 1206 case IPOPT_SSRR: 1207 if (ip_allowsrcrt == 0) { 1208 type = ICMP_UNREACH; 1209 code = ICMP_UNREACH_NET_PROHIB; 1210 goto bad; 1211 } 1212 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1213 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1214 goto bad; 1215 } 1216 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1217 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1218 goto bad; 1219 } 1220 ipaddr.sin_addr = ip->ip_dst; 1221 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1222 if (ia == 0) { 1223 if (opt == IPOPT_SSRR) { 1224 type = ICMP_UNREACH; 1225 code = ICMP_UNREACH_SRCFAIL; 1226 goto bad; 1227 } 1228 /* 1229 * Loose routing, and not at next destination 1230 * yet; nothing to do except forward. 1231 */ 1232 break; 1233 } 1234 off--; /* 0 origin */ 1235 if ((off + sizeof(struct in_addr)) > optlen) { 1236 /* 1237 * End of source route. Should be for us. 1238 */ 1239 save_rte(cp, ip->ip_src); 1240 break; 1241 } 1242 /* 1243 * locate outgoing interface 1244 */ 1245 bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr, 1246 sizeof(ipaddr.sin_addr)); 1247 if (opt == IPOPT_SSRR) 1248 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1249 else 1250 ia = ip_rtaddr(ipaddr.sin_addr); 1251 if (ia == 0) { 1252 type = ICMP_UNREACH; 1253 code = ICMP_UNREACH_SRCFAIL; 1254 goto bad; 1255 } 1256 ip->ip_dst = ipaddr.sin_addr; 1257 bcopy((caddr_t)&ia->ia_addr.sin_addr, 1258 (caddr_t)(cp + off), sizeof(struct in_addr)); 1259 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1260 /* 1261 * Let ip_intr's mcast routing check handle mcast pkts 1262 */ 1263 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 1264 break; 1265 1266 case IPOPT_RR: 1267 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1268 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1269 goto bad; 1270 } 1271 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1272 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1273 goto bad; 1274 } 1275 /* 1276 * If no space remains, ignore. 1277 */ 1278 off--; /* 0 origin */ 1279 if ((off + sizeof(struct in_addr)) > optlen) 1280 break; 1281 bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr, 1282 sizeof(ipaddr.sin_addr)); 1283 /* 1284 * locate outgoing interface; if we're the destination, 1285 * use the incoming interface (should be same). 1286 */ 1287 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))) 1288 == NULL && 1289 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) { 1290 type = ICMP_UNREACH; 1291 code = ICMP_UNREACH_HOST; 1292 goto bad; 1293 } 1294 bcopy((caddr_t)&ia->ia_addr.sin_addr, 1295 (caddr_t)(cp + off), sizeof(struct in_addr)); 1296 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1297 break; 1298 1299 case IPOPT_TS: 1300 code = cp - (u_char *)ip; 1301 ipt = (struct ip_timestamp *)cp; 1302 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) { 1303 code = (u_char *)&ipt->ipt_len - (u_char *)ip; 1304 goto bad; 1305 } 1306 if (ipt->ipt_ptr < 5) { 1307 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip; 1308 goto bad; 1309 } 1310 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 1311 if (++ipt->ipt_oflw == 0) { 1312 code = (u_char *)&ipt->ipt_ptr - 1313 (u_char *)ip; 1314 goto bad; 1315 } 1316 break; 1317 } 1318 cp0 = (cp + ipt->ipt_ptr - 1); 1319 switch (ipt->ipt_flg) { 1320 1321 case IPOPT_TS_TSONLY: 1322 break; 1323 1324 case IPOPT_TS_TSANDADDR: 1325 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1326 sizeof(struct in_addr) > ipt->ipt_len) { 1327 code = (u_char *)&ipt->ipt_ptr - 1328 (u_char *)ip; 1329 goto bad; 1330 } 1331 ipaddr.sin_addr = dst; 1332 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr), 1333 m->m_pkthdr.rcvif)); 1334 if (ia == 0) 1335 continue; 1336 bcopy(&ia->ia_addr.sin_addr, 1337 cp0, sizeof(struct in_addr)); 1338 ipt->ipt_ptr += sizeof(struct in_addr); 1339 break; 1340 1341 case IPOPT_TS_PRESPEC: 1342 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1343 sizeof(struct in_addr) > ipt->ipt_len) { 1344 code = (u_char *)&ipt->ipt_ptr - 1345 (u_char *)ip; 1346 goto bad; 1347 } 1348 bcopy(cp0, &ipaddr.sin_addr, 1349 sizeof(struct in_addr)); 1350 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))) 1351 == NULL) 1352 continue; 1353 ipt->ipt_ptr += sizeof(struct in_addr); 1354 break; 1355 1356 default: 1357 /* XXX can't take &ipt->ipt_flg */ 1358 code = (u_char *)&ipt->ipt_ptr - 1359 (u_char *)ip + 1; 1360 goto bad; 1361 } 1362 ntime = iptime(); 1363 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */ 1364 bcopy(cp0, (caddr_t)cp + ipt->ipt_ptr - 1, 1365 sizeof(n_time)); 1366 ipt->ipt_ptr += sizeof(n_time); 1367 } 1368 } 1369 if (forward) { 1370 if (ip_forwsrcrt == 0) { 1371 type = ICMP_UNREACH; 1372 code = ICMP_UNREACH_SRCFAIL; 1373 goto bad; 1374 } 1375 ip_forward(m, 1); 1376 return (1); 1377 } 1378 return (0); 1379 bad: 1380 icmp_error(m, type, code, 0, 0); 1381 ipstat.ips_badoptions++; 1382 return (1); 1383 } 1384 1385 /* 1386 * Given address of next destination (final or next hop), 1387 * return internet address info of interface to be used to get there. 1388 */ 1389 struct in_ifaddr * 1390 ip_rtaddr(dst) 1391 struct in_addr dst; 1392 { 1393 struct sockaddr_in *sin; 1394 1395 sin = satosin(&ipforward_rt.ro_dst); 1396 1397 if (ipforward_rt.ro_rt == 0 || !in_hosteq(dst, sin->sin_addr)) { 1398 if (ipforward_rt.ro_rt) { 1399 RTFREE(ipforward_rt.ro_rt); 1400 ipforward_rt.ro_rt = 0; 1401 } 1402 sin->sin_family = AF_INET; 1403 sin->sin_len = sizeof(*sin); 1404 sin->sin_addr = dst; 1405 1406 rtalloc(&ipforward_rt); 1407 } 1408 if (ipforward_rt.ro_rt == 0) 1409 return ((struct in_ifaddr *)0); 1410 return (ifatoia(ipforward_rt.ro_rt->rt_ifa)); 1411 } 1412 1413 /* 1414 * Save incoming source route for use in replies, 1415 * to be picked up later by ip_srcroute if the receiver is interested. 1416 */ 1417 void 1418 save_rte(option, dst) 1419 u_char *option; 1420 struct in_addr dst; 1421 { 1422 unsigned olen; 1423 1424 olen = option[IPOPT_OLEN]; 1425 #ifdef DIAGNOSTIC 1426 if (ipprintfs) 1427 printf("save_rte: olen %d\n", olen); 1428 #endif /* 0 */ 1429 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1430 return; 1431 bcopy((caddr_t)option, (caddr_t)ip_srcrt.srcopt, olen); 1432 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1433 ip_srcrt.dst = dst; 1434 } 1435 1436 /* 1437 * Retrieve incoming source route for use in replies, 1438 * in the same form used by setsockopt. 1439 * The first hop is placed before the options, will be removed later. 1440 */ 1441 struct mbuf * 1442 ip_srcroute() 1443 { 1444 struct in_addr *p, *q; 1445 struct mbuf *m; 1446 1447 if (ip_nhops == 0) 1448 return ((struct mbuf *)0); 1449 m = m_get(M_DONTWAIT, MT_SOOPTS); 1450 if (m == 0) 1451 return ((struct mbuf *)0); 1452 1453 MCLAIM(m, &inetdomain.dom_mowner); 1454 #define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1455 1456 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1457 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1458 OPTSIZ; 1459 #ifdef DIAGNOSTIC 1460 if (ipprintfs) 1461 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1462 #endif 1463 1464 /* 1465 * First save first hop for return route 1466 */ 1467 p = &ip_srcrt.route[ip_nhops - 1]; 1468 *(mtod(m, struct in_addr *)) = *p--; 1469 #ifdef DIAGNOSTIC 1470 if (ipprintfs) 1471 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1472 #endif 1473 1474 /* 1475 * Copy option fields and padding (nop) to mbuf. 1476 */ 1477 ip_srcrt.nop = IPOPT_NOP; 1478 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1479 bcopy((caddr_t)&ip_srcrt.nop, 1480 mtod(m, caddr_t) + sizeof(struct in_addr), OPTSIZ); 1481 q = (struct in_addr *)(mtod(m, caddr_t) + 1482 sizeof(struct in_addr) + OPTSIZ); 1483 #undef OPTSIZ 1484 /* 1485 * Record return path as an IP source route, 1486 * reversing the path (pointers are now aligned). 1487 */ 1488 while (p >= ip_srcrt.route) { 1489 #ifdef DIAGNOSTIC 1490 if (ipprintfs) 1491 printf(" %x", ntohl(q->s_addr)); 1492 #endif 1493 *q++ = *p--; 1494 } 1495 /* 1496 * Last hop goes to final destination. 1497 */ 1498 *q = ip_srcrt.dst; 1499 #ifdef DIAGNOSTIC 1500 if (ipprintfs) 1501 printf(" %x\n", ntohl(q->s_addr)); 1502 #endif 1503 return (m); 1504 } 1505 1506 /* 1507 * Strip out IP options, at higher 1508 * level protocol in the kernel. 1509 * Second argument is buffer to which options 1510 * will be moved, and return value is their length. 1511 * XXX should be deleted; last arg currently ignored. 1512 */ 1513 void 1514 ip_stripoptions(m, mopt) 1515 struct mbuf *m; 1516 struct mbuf *mopt; 1517 { 1518 int i; 1519 struct ip *ip = mtod(m, struct ip *); 1520 caddr_t opts; 1521 int olen; 1522 1523 olen = (ip->ip_hl << 2) - sizeof (struct ip); 1524 opts = (caddr_t)(ip + 1); 1525 i = m->m_len - (sizeof (struct ip) + olen); 1526 bcopy(opts + olen, opts, (unsigned)i); 1527 m->m_len -= olen; 1528 if (m->m_flags & M_PKTHDR) 1529 m->m_pkthdr.len -= olen; 1530 ip->ip_len = htons(ntohs(ip->ip_len) - olen); 1531 ip->ip_hl = sizeof (struct ip) >> 2; 1532 } 1533 1534 const int inetctlerrmap[PRC_NCMDS] = { 1535 0, 0, 0, 0, 1536 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1537 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1538 EMSGSIZE, EHOSTUNREACH, 0, 0, 1539 0, 0, 0, 0, 1540 ENOPROTOOPT 1541 }; 1542 1543 /* 1544 * Forward a packet. If some error occurs return the sender 1545 * an icmp packet. Note we can't always generate a meaningful 1546 * icmp message because icmp doesn't have a large enough repertoire 1547 * of codes and types. 1548 * 1549 * If not forwarding, just drop the packet. This could be confusing 1550 * if ipforwarding was zero but some routing protocol was advancing 1551 * us as a gateway to somewhere. However, we must let the routing 1552 * protocol deal with that. 1553 * 1554 * The srcrt parameter indicates whether the packet is being forwarded 1555 * via a source route. 1556 */ 1557 void 1558 ip_forward(m, srcrt) 1559 struct mbuf *m; 1560 int srcrt; 1561 { 1562 struct ip *ip = mtod(m, struct ip *); 1563 struct sockaddr_in *sin; 1564 struct rtentry *rt; 1565 int error, type = 0, code = 0; 1566 struct mbuf *mcopy; 1567 n_long dest; 1568 struct ifnet *destifp; 1569 #ifdef IPSEC 1570 struct ifnet dummyifp; 1571 #endif 1572 1573 /* 1574 * We are now in the output path. 1575 */ 1576 MCLAIM(m, &ip_tx_mowner); 1577 1578 /* 1579 * Clear any in-bound checksum flags for this packet. 1580 */ 1581 m->m_pkthdr.csum_flags = 0; 1582 1583 dest = 0; 1584 #ifdef DIAGNOSTIC 1585 if (ipprintfs) 1586 printf("forward: src %2.2x dst %2.2x ttl %x\n", 1587 ntohl(ip->ip_src.s_addr), 1588 ntohl(ip->ip_dst.s_addr), ip->ip_ttl); 1589 #endif 1590 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) { 1591 ipstat.ips_cantforward++; 1592 m_freem(m); 1593 return; 1594 } 1595 if (ip->ip_ttl <= IPTTLDEC) { 1596 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1597 return; 1598 } 1599 ip->ip_ttl -= IPTTLDEC; 1600 1601 sin = satosin(&ipforward_rt.ro_dst); 1602 if ((rt = ipforward_rt.ro_rt) == 0 || 1603 !in_hosteq(ip->ip_dst, sin->sin_addr)) { 1604 if (ipforward_rt.ro_rt) { 1605 RTFREE(ipforward_rt.ro_rt); 1606 ipforward_rt.ro_rt = 0; 1607 } 1608 sin->sin_family = AF_INET; 1609 sin->sin_len = sizeof(struct sockaddr_in); 1610 sin->sin_addr = ip->ip_dst; 1611 1612 rtalloc(&ipforward_rt); 1613 if (ipforward_rt.ro_rt == 0) { 1614 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0); 1615 return; 1616 } 1617 rt = ipforward_rt.ro_rt; 1618 } 1619 1620 /* 1621 * Save at most 68 bytes of the packet in case 1622 * we need to generate an ICMP message to the src. 1623 * Pullup to avoid sharing mbuf cluster between m and mcopy. 1624 */ 1625 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT); 1626 if (mcopy) 1627 mcopy = m_pullup(mcopy, ip->ip_hl << 2); 1628 1629 /* 1630 * If forwarding packet using same interface that it came in on, 1631 * perhaps should send a redirect to sender to shortcut a hop. 1632 * Only send redirect if source is sending directly to us, 1633 * and if packet was not source routed (or has any options). 1634 * Also, don't send redirect if forwarding using a default route 1635 * or a route modified by a redirect. 1636 */ 1637 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1638 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1639 !in_nullhost(satosin(rt_key(rt))->sin_addr) && 1640 ipsendredirects && !srcrt) { 1641 if (rt->rt_ifa && 1642 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1643 ifatoia(rt->rt_ifa)->ia_subnet) { 1644 if (rt->rt_flags & RTF_GATEWAY) 1645 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1646 else 1647 dest = ip->ip_dst.s_addr; 1648 /* 1649 * Router requirements says to only send host 1650 * redirects. 1651 */ 1652 type = ICMP_REDIRECT; 1653 code = ICMP_REDIRECT_HOST; 1654 #ifdef DIAGNOSTIC 1655 if (ipprintfs) 1656 printf("redirect (%d) to %x\n", code, 1657 (u_int32_t)dest); 1658 #endif 1659 } 1660 } 1661 1662 #ifdef IPSEC 1663 /* Don't lookup socket in forwarding case */ 1664 (void)ipsec_setsocket(m, NULL); 1665 #endif 1666 error = ip_output(m, (struct mbuf *)0, &ipforward_rt, 1667 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 0); 1668 if (error) 1669 ipstat.ips_cantforward++; 1670 else { 1671 ipstat.ips_forward++; 1672 if (type) 1673 ipstat.ips_redirectsent++; 1674 else { 1675 if (mcopy) { 1676 #ifdef GATEWAY 1677 if (mcopy->m_flags & M_CANFASTFWD) 1678 ipflow_create(&ipforward_rt, mcopy); 1679 #endif 1680 m_freem(mcopy); 1681 } 1682 return; 1683 } 1684 } 1685 if (mcopy == NULL) 1686 return; 1687 destifp = NULL; 1688 1689 switch (error) { 1690 1691 case 0: /* forwarded, but need redirect */ 1692 /* type, code set above */ 1693 break; 1694 1695 case ENETUNREACH: /* shouldn't happen, checked above */ 1696 case EHOSTUNREACH: 1697 case ENETDOWN: 1698 case EHOSTDOWN: 1699 default: 1700 type = ICMP_UNREACH; 1701 code = ICMP_UNREACH_HOST; 1702 break; 1703 1704 case EMSGSIZE: 1705 type = ICMP_UNREACH; 1706 code = ICMP_UNREACH_NEEDFRAG; 1707 #ifndef IPSEC 1708 if (ipforward_rt.ro_rt) 1709 destifp = ipforward_rt.ro_rt->rt_ifp; 1710 #else 1711 /* 1712 * If the packet is routed over IPsec tunnel, tell the 1713 * originator the tunnel MTU. 1714 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 1715 * XXX quickhack!!! 1716 */ 1717 if (ipforward_rt.ro_rt) { 1718 struct secpolicy *sp; 1719 int ipsecerror; 1720 size_t ipsechdr; 1721 struct route *ro; 1722 1723 sp = ipsec4_getpolicybyaddr(mcopy, 1724 IPSEC_DIR_OUTBOUND, 1725 IP_FORWARDING, 1726 &ipsecerror); 1727 1728 if (sp == NULL) 1729 destifp = ipforward_rt.ro_rt->rt_ifp; 1730 else { 1731 /* count IPsec header size */ 1732 ipsechdr = ipsec4_hdrsiz(mcopy, 1733 IPSEC_DIR_OUTBOUND, 1734 NULL); 1735 1736 /* 1737 * find the correct route for outer IPv4 1738 * header, compute tunnel MTU. 1739 * 1740 * XXX BUG ALERT 1741 * The "dummyifp" code relies upon the fact 1742 * that icmp_error() touches only ifp->if_mtu. 1743 */ 1744 /*XXX*/ 1745 destifp = NULL; 1746 if (sp->req != NULL 1747 && sp->req->sav != NULL 1748 && sp->req->sav->sah != NULL) { 1749 ro = &sp->req->sav->sah->sa_route; 1750 if (ro->ro_rt && ro->ro_rt->rt_ifp) { 1751 dummyifp.if_mtu = 1752 ro->ro_rt->rt_rmx.rmx_mtu ? 1753 ro->ro_rt->rt_rmx.rmx_mtu : 1754 ro->ro_rt->rt_ifp->if_mtu; 1755 dummyifp.if_mtu -= ipsechdr; 1756 destifp = &dummyifp; 1757 } 1758 } 1759 1760 key_freesp(sp); 1761 } 1762 } 1763 #endif /*IPSEC*/ 1764 ipstat.ips_cantfrag++; 1765 break; 1766 1767 case ENOBUFS: 1768 #if 1 1769 /* 1770 * a router should not generate ICMP_SOURCEQUENCH as 1771 * required in RFC1812 Requirements for IP Version 4 Routers. 1772 * source quench could be a big problem under DoS attacks, 1773 * or if the underlying interface is rate-limited. 1774 */ 1775 if (mcopy) 1776 m_freem(mcopy); 1777 return; 1778 #else 1779 type = ICMP_SOURCEQUENCH; 1780 code = 0; 1781 break; 1782 #endif 1783 } 1784 icmp_error(mcopy, type, code, dest, destifp); 1785 } 1786 1787 void 1788 ip_savecontrol(inp, mp, ip, m) 1789 struct inpcb *inp; 1790 struct mbuf **mp; 1791 struct ip *ip; 1792 struct mbuf *m; 1793 { 1794 1795 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 1796 struct timeval tv; 1797 1798 microtime(&tv); 1799 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1800 SCM_TIMESTAMP, SOL_SOCKET); 1801 if (*mp) 1802 mp = &(*mp)->m_next; 1803 } 1804 if (inp->inp_flags & INP_RECVDSTADDR) { 1805 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst, 1806 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 1807 if (*mp) 1808 mp = &(*mp)->m_next; 1809 } 1810 #ifdef notyet 1811 /* 1812 * XXX 1813 * Moving these out of udp_input() made them even more broken 1814 * than they already were. 1815 * - fenner@parc.xerox.com 1816 */ 1817 /* options were tossed already */ 1818 if (inp->inp_flags & INP_RECVOPTS) { 1819 *mp = sbcreatecontrol((caddr_t) opts_deleted_above, 1820 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 1821 if (*mp) 1822 mp = &(*mp)->m_next; 1823 } 1824 /* ip_srcroute doesn't do what we want here, need to fix */ 1825 if (inp->inp_flags & INP_RECVRETOPTS) { 1826 *mp = sbcreatecontrol((caddr_t) ip_srcroute(), 1827 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 1828 if (*mp) 1829 mp = &(*mp)->m_next; 1830 } 1831 #endif 1832 if (inp->inp_flags & INP_RECVIF) { 1833 struct sockaddr_dl sdl; 1834 1835 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]); 1836 sdl.sdl_family = AF_LINK; 1837 sdl.sdl_index = m->m_pkthdr.rcvif ? 1838 m->m_pkthdr.rcvif->if_index : 0; 1839 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0; 1840 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len, 1841 IP_RECVIF, IPPROTO_IP); 1842 if (*mp) 1843 mp = &(*mp)->m_next; 1844 } 1845 } 1846 1847 int 1848 ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 1849 int *name; 1850 u_int namelen; 1851 void *oldp; 1852 size_t *oldlenp; 1853 void *newp; 1854 size_t newlen; 1855 { 1856 extern int subnetsarelocal, hostzeroisbroadcast; 1857 1858 int error, old; 1859 1860 /* All sysctl names at this level are terminal. */ 1861 if (namelen != 1) 1862 return (ENOTDIR); 1863 1864 switch (name[0]) { 1865 case IPCTL_FORWARDING: 1866 return (sysctl_int(oldp, oldlenp, newp, newlen, &ipforwarding)); 1867 case IPCTL_SENDREDIRECTS: 1868 return (sysctl_int(oldp, oldlenp, newp, newlen, 1869 &ipsendredirects)); 1870 case IPCTL_DEFTTL: 1871 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_defttl)); 1872 #ifdef notyet 1873 case IPCTL_DEFMTU: 1874 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu)); 1875 #endif 1876 case IPCTL_FORWSRCRT: 1877 /* Don't allow this to change in a secure environment. */ 1878 if (securelevel > 0) 1879 return (sysctl_rdint(oldp, oldlenp, newp, 1880 ip_forwsrcrt)); 1881 else 1882 return (sysctl_int(oldp, oldlenp, newp, newlen, 1883 &ip_forwsrcrt)); 1884 case IPCTL_DIRECTEDBCAST: 1885 return (sysctl_int(oldp, oldlenp, newp, newlen, 1886 &ip_directedbcast)); 1887 case IPCTL_ALLOWSRCRT: 1888 return (sysctl_int(oldp, oldlenp, newp, newlen, 1889 &ip_allowsrcrt)); 1890 case IPCTL_SUBNETSARELOCAL: 1891 return (sysctl_int(oldp, oldlenp, newp, newlen, 1892 &subnetsarelocal)); 1893 case IPCTL_MTUDISC: 1894 error = sysctl_int(oldp, oldlenp, newp, newlen, 1895 &ip_mtudisc); 1896 if (error == 0 && ip_mtudisc == 0) 1897 rt_timer_queue_remove_all(ip_mtudisc_timeout_q, TRUE); 1898 return error; 1899 case IPCTL_ANONPORTMIN: 1900 old = anonportmin; 1901 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmin); 1902 if (anonportmin >= anonportmax || anonportmin < 0 1903 || anonportmin > 65535 1904 #ifndef IPNOPRIVPORTS 1905 || anonportmin < IPPORT_RESERVED 1906 #endif 1907 ) { 1908 anonportmin = old; 1909 return (EINVAL); 1910 } 1911 return (error); 1912 case IPCTL_ANONPORTMAX: 1913 old = anonportmax; 1914 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmax); 1915 if (anonportmin >= anonportmax || anonportmax < 0 1916 || anonportmax > 65535 1917 #ifndef IPNOPRIVPORTS 1918 || anonportmax < IPPORT_RESERVED 1919 #endif 1920 ) { 1921 anonportmax = old; 1922 return (EINVAL); 1923 } 1924 return (error); 1925 case IPCTL_MTUDISCTIMEOUT: 1926 old = ip_mtudisc_timeout; 1927 error = sysctl_int(oldp, oldlenp, newp, newlen, 1928 &ip_mtudisc_timeout); 1929 if (ip_mtudisc_timeout < 0) { 1930 ip_mtudisc_timeout = old; 1931 return (EINVAL); 1932 } 1933 if (error == 0) 1934 rt_timer_queue_change(ip_mtudisc_timeout_q, 1935 ip_mtudisc_timeout); 1936 return (error); 1937 #ifdef GATEWAY 1938 case IPCTL_MAXFLOWS: 1939 { 1940 int s; 1941 1942 error = sysctl_int(oldp, oldlenp, newp, newlen, 1943 &ip_maxflows); 1944 s = splsoftnet(); 1945 ipflow_reap(0); 1946 splx(s); 1947 return (error); 1948 } 1949 #endif 1950 case IPCTL_HOSTZEROBROADCAST: 1951 return (sysctl_int(oldp, oldlenp, newp, newlen, 1952 &hostzeroisbroadcast)); 1953 #if NGIF > 0 1954 case IPCTL_GIF_TTL: 1955 return (sysctl_int(oldp, oldlenp, newp, newlen, 1956 &ip_gif_ttl)); 1957 #endif 1958 1959 #if NGRE > 0 1960 case IPCTL_GRE_TTL: 1961 return (sysctl_int(oldp, oldlenp, newp, newlen, 1962 &ip_gre_ttl)); 1963 #endif 1964 1965 #ifndef IPNOPRIVPORTS 1966 case IPCTL_LOWPORTMIN: 1967 old = lowportmin; 1968 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmin); 1969 if (lowportmin >= lowportmax 1970 || lowportmin > IPPORT_RESERVEDMAX 1971 || lowportmin < IPPORT_RESERVEDMIN 1972 ) { 1973 lowportmin = old; 1974 return (EINVAL); 1975 } 1976 return (error); 1977 case IPCTL_LOWPORTMAX: 1978 old = lowportmax; 1979 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmax); 1980 if (lowportmin >= lowportmax 1981 || lowportmax > IPPORT_RESERVEDMAX 1982 || lowportmax < IPPORT_RESERVEDMIN 1983 ) { 1984 lowportmax = old; 1985 return (EINVAL); 1986 } 1987 return (error); 1988 #endif 1989 1990 case IPCTL_MAXFRAGPACKETS: 1991 return (sysctl_int(oldp, oldlenp, newp, newlen, 1992 &ip_maxfragpackets)); 1993 1994 case IPCTL_CHECKINTERFACE: 1995 return (sysctl_int(oldp, oldlenp, newp, newlen, 1996 &ip_checkinterface)); 1997 default: 1998 return (EOPNOTSUPP); 1999 } 2000 /* NOTREACHED */ 2001 } 2002