1 /* $NetBSD: ip_input.c,v 1.170 2003/07/03 05:03:53 itojun 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 1.170 2003/07/03 05:03:53 itojun 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 int srcrt = 0; 437 438 MCLAIM(m, &ip_rx_mowner); 439 #ifdef DIAGNOSTIC 440 if ((m->m_flags & M_PKTHDR) == 0) 441 panic("ipintr no HDR"); 442 #endif 443 #ifdef IPSEC 444 /* 445 * should the inner packet be considered authentic? 446 * see comment in ah4_input(). 447 */ 448 if (m) { 449 m->m_flags &= ~M_AUTHIPHDR; 450 m->m_flags &= ~M_AUTHIPDGM; 451 } 452 #endif 453 454 /* 455 * If no IP addresses have been set yet but the interfaces 456 * are receiving, can't do anything with incoming packets yet. 457 */ 458 if (TAILQ_FIRST(&in_ifaddr) == 0) 459 goto bad; 460 ipstat.ips_total++; 461 /* 462 * If the IP header is not aligned, slurp it up into a new 463 * mbuf with space for link headers, in the event we forward 464 * it. Otherwise, if it is aligned, make sure the entire 465 * base IP header is in the first mbuf of the chain. 466 */ 467 if (IP_HDR_ALIGNED_P(mtod(m, caddr_t)) == 0) { 468 if ((m = m_copyup(m, sizeof(struct ip), 469 (max_linkhdr + 3) & ~3)) == NULL) { 470 /* XXXJRT new stat, please */ 471 ipstat.ips_toosmall++; 472 return; 473 } 474 } else if (__predict_false(m->m_len < sizeof (struct ip))) { 475 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) { 476 ipstat.ips_toosmall++; 477 return; 478 } 479 } 480 ip = mtod(m, struct ip *); 481 if (ip->ip_v != IPVERSION) { 482 ipstat.ips_badvers++; 483 goto bad; 484 } 485 hlen = ip->ip_hl << 2; 486 if (hlen < sizeof(struct ip)) { /* minimum header length */ 487 ipstat.ips_badhlen++; 488 goto bad; 489 } 490 if (hlen > m->m_len) { 491 if ((m = m_pullup(m, hlen)) == 0) { 492 ipstat.ips_badhlen++; 493 return; 494 } 495 ip = mtod(m, struct ip *); 496 } 497 498 /* 499 * RFC1122: packets with a multicast source address are 500 * not allowed. 501 */ 502 if (IN_MULTICAST(ip->ip_src.s_addr)) { 503 ipstat.ips_badaddr++; 504 goto bad; 505 } 506 507 /* 127/8 must not appear on wire - RFC1122 */ 508 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 509 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 510 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 511 ipstat.ips_badaddr++; 512 goto bad; 513 } 514 } 515 516 switch (m->m_pkthdr.csum_flags & 517 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) | 518 M_CSUM_IPv4_BAD)) { 519 case M_CSUM_IPv4|M_CSUM_IPv4_BAD: 520 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad); 521 goto badcsum; 522 523 case M_CSUM_IPv4: 524 /* Checksum was okay. */ 525 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok); 526 break; 527 528 default: 529 /* Must compute it ourselves. */ 530 INET_CSUM_COUNTER_INCR(&ip_swcsum); 531 if (in_cksum(m, hlen) != 0) 532 goto bad; 533 break; 534 } 535 536 /* Retrieve the packet length. */ 537 len = ntohs(ip->ip_len); 538 539 /* 540 * Check for additional length bogosity 541 */ 542 if (len < hlen) { 543 ipstat.ips_badlen++; 544 goto bad; 545 } 546 547 /* 548 * Check that the amount of data in the buffers 549 * is as at least much as the IP header would have us expect. 550 * Trim mbufs if longer than we expect. 551 * Drop packet if shorter than we expect. 552 */ 553 if (m->m_pkthdr.len < len) { 554 ipstat.ips_tooshort++; 555 goto bad; 556 } 557 if (m->m_pkthdr.len > len) { 558 if (m->m_len == m->m_pkthdr.len) { 559 m->m_len = len; 560 m->m_pkthdr.len = len; 561 } else 562 m_adj(m, len - m->m_pkthdr.len); 563 } 564 565 #ifdef IPSEC 566 /* ipflow (IP fast forwarding) is not compatible with IPsec. */ 567 m->m_flags &= ~M_CANFASTFWD; 568 #else 569 /* 570 * Assume that we can create a fast-forward IP flow entry 571 * based on this packet. 572 */ 573 m->m_flags |= M_CANFASTFWD; 574 #endif 575 576 #ifdef PFIL_HOOKS 577 /* 578 * Run through list of hooks for input packets. If there are any 579 * filters which require that additional packets in the flow are 580 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 581 * Note that filters must _never_ set this flag, as another filter 582 * in the list may have previously cleared it. 583 */ 584 /* 585 * let ipfilter look at packet on the wire, 586 * not the decapsulated packet. 587 */ 588 #ifdef IPSEC 589 if (!ipsec_getnhist(m)) 590 #else 591 if (1) 592 #endif 593 { 594 struct in_addr odst; 595 596 odst = ip->ip_dst; 597 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif, 598 PFIL_IN) != 0) 599 return; 600 if (m == NULL) 601 return; 602 ip = mtod(m, struct ip *); 603 hlen = ip->ip_hl << 2; 604 srcrt = (odst.s_addr != ip->ip_dst.s_addr); 605 } 606 #endif /* PFIL_HOOKS */ 607 608 #ifdef ALTQ 609 /* XXX Temporary until ALTQ is changed to use a pfil hook */ 610 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) { 611 /* packet dropped by traffic conditioner */ 612 return; 613 } 614 #endif 615 616 /* 617 * Process options and, if not destined for us, 618 * ship it on. ip_dooptions returns 1 when an 619 * error was detected (causing an icmp message 620 * to be sent and the original packet to be freed). 621 */ 622 ip_nhops = 0; /* for source routed packets */ 623 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 624 return; 625 626 /* 627 * Enable a consistency check between the destination address 628 * and the arrival interface for a unicast packet (the RFC 1122 629 * strong ES model) if IP forwarding is disabled and the packet 630 * is not locally generated. 631 * 632 * XXX - Checking also should be disabled if the destination 633 * address is ipnat'ed to a different interface. 634 * 635 * XXX - Checking is incompatible with IP aliases added 636 * to the loopback interface instead of the interface where 637 * the packets are received. 638 * 639 * XXX - We need to add a per ifaddr flag for this so that 640 * we get finer grain control. 641 */ 642 checkif = ip_checkinterface && (ipforwarding == 0) && 643 (m->m_pkthdr.rcvif != NULL) && 644 ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0); 645 646 /* 647 * Check our list of addresses, to see if the packet is for us. 648 * 649 * Traditional 4.4BSD did not consult IFF_UP at all. 650 * The behavior here is to treat addresses on !IFF_UP interface 651 * as not mine. 652 */ 653 downmatch = 0; 654 LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) { 655 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) { 656 if (checkif && ia->ia_ifp != m->m_pkthdr.rcvif) 657 continue; 658 if ((ia->ia_ifp->if_flags & IFF_UP) != 0) 659 break; 660 else 661 downmatch++; 662 } 663 } 664 if (ia != NULL) 665 goto ours; 666 if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 667 TAILQ_FOREACH(ifa, &m->m_pkthdr.rcvif->if_addrlist, ifa_list) { 668 if (ifa->ifa_addr->sa_family != AF_INET) 669 continue; 670 ia = ifatoia(ifa); 671 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 672 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 673 /* 674 * Look for all-0's host part (old broadcast addr), 675 * either for subnet or net. 676 */ 677 ip->ip_dst.s_addr == ia->ia_subnet || 678 ip->ip_dst.s_addr == ia->ia_net) 679 goto ours; 680 /* 681 * An interface with IP address zero accepts 682 * all packets that arrive on that interface. 683 */ 684 if (in_nullhost(ia->ia_addr.sin_addr)) 685 goto ours; 686 } 687 } 688 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 689 struct in_multi *inm; 690 #ifdef MROUTING 691 extern struct socket *ip_mrouter; 692 693 if (M_READONLY(m)) { 694 if ((m = m_pullup(m, hlen)) == 0) { 695 ipstat.ips_toosmall++; 696 return; 697 } 698 ip = mtod(m, struct ip *); 699 } 700 701 if (ip_mrouter) { 702 /* 703 * If we are acting as a multicast router, all 704 * incoming multicast packets are passed to the 705 * kernel-level multicast forwarding function. 706 * The packet is returned (relatively) intact; if 707 * ip_mforward() returns a non-zero value, the packet 708 * must be discarded, else it may be accepted below. 709 * 710 * (The IP ident field is put in the same byte order 711 * as expected when ip_mforward() is called from 712 * ip_output().) 713 */ 714 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 715 ipstat.ips_cantforward++; 716 m_freem(m); 717 return; 718 } 719 720 /* 721 * The process-level routing demon needs to receive 722 * all multicast IGMP packets, whether or not this 723 * host belongs to their destination groups. 724 */ 725 if (ip->ip_p == IPPROTO_IGMP) 726 goto ours; 727 ipstat.ips_forward++; 728 } 729 #endif 730 /* 731 * See if we belong to the destination multicast group on the 732 * arrival interface. 733 */ 734 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 735 if (inm == NULL) { 736 ipstat.ips_cantforward++; 737 m_freem(m); 738 return; 739 } 740 goto ours; 741 } 742 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 743 in_nullhost(ip->ip_dst)) 744 goto ours; 745 746 /* 747 * Not for us; forward if possible and desirable. 748 */ 749 if (ipforwarding == 0) { 750 ipstat.ips_cantforward++; 751 m_freem(m); 752 } else { 753 /* 754 * If ip_dst matched any of my address on !IFF_UP interface, 755 * and there's no IFF_UP interface that matches ip_dst, 756 * send icmp unreach. Forwarding it will result in in-kernel 757 * forwarding loop till TTL goes to 0. 758 */ 759 if (downmatch) { 760 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0); 761 ipstat.ips_cantforward++; 762 return; 763 } 764 #ifdef IPSEC 765 if (ipsec4_in_reject(m, NULL)) { 766 ipsecstat.in_polvio++; 767 goto bad; 768 } 769 #endif 770 771 ip_forward(m, srcrt); 772 } 773 return; 774 775 ours: 776 /* 777 * If offset or IP_MF are set, must reassemble. 778 * Otherwise, nothing need be done. 779 * (We could look in the reassembly queue to see 780 * if the packet was previously fragmented, 781 * but it's not worth the time; just let them time out.) 782 */ 783 if (ip->ip_off & ~htons(IP_DF|IP_RF)) { 784 if (M_READONLY(m)) { 785 if ((m = m_pullup(m, hlen)) == NULL) { 786 ipstat.ips_toosmall++; 787 goto bad; 788 } 789 ip = mtod(m, struct ip *); 790 } 791 792 /* 793 * Look for queue of fragments 794 * of this datagram. 795 */ 796 IPQ_LOCK(); 797 LIST_FOREACH(fp, &ipq, ipq_q) 798 if (ip->ip_id == fp->ipq_id && 799 in_hosteq(ip->ip_src, fp->ipq_src) && 800 in_hosteq(ip->ip_dst, fp->ipq_dst) && 801 ip->ip_p == fp->ipq_p) 802 goto found; 803 fp = 0; 804 found: 805 806 /* 807 * Adjust ip_len to not reflect header, 808 * set ipqe_mff if more fragments are expected, 809 * convert offset of this to bytes. 810 */ 811 ip->ip_len = htons(ntohs(ip->ip_len) - hlen); 812 mff = (ip->ip_off & htons(IP_MF)) != 0; 813 if (mff) { 814 /* 815 * Make sure that fragments have a data length 816 * that's a non-zero multiple of 8 bytes. 817 */ 818 if (ntohs(ip->ip_len) == 0 || 819 (ntohs(ip->ip_len) & 0x7) != 0) { 820 ipstat.ips_badfrags++; 821 IPQ_UNLOCK(); 822 goto bad; 823 } 824 } 825 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3); 826 827 /* 828 * If datagram marked as having more fragments 829 * or if this is not the first fragment, 830 * attempt reassembly; if it succeeds, proceed. 831 */ 832 if (mff || ip->ip_off != htons(0)) { 833 ipstat.ips_fragments++; 834 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 835 if (ipqe == NULL) { 836 ipstat.ips_rcvmemdrop++; 837 IPQ_UNLOCK(); 838 goto bad; 839 } 840 ipqe->ipqe_mff = mff; 841 ipqe->ipqe_m = m; 842 ipqe->ipqe_ip = ip; 843 m = ip_reass(ipqe, fp); 844 if (m == 0) { 845 IPQ_UNLOCK(); 846 return; 847 } 848 ipstat.ips_reassembled++; 849 ip = mtod(m, struct ip *); 850 hlen = ip->ip_hl << 2; 851 ip->ip_len = htons(ntohs(ip->ip_len) + hlen); 852 } else 853 if (fp) 854 ip_freef(fp); 855 IPQ_UNLOCK(); 856 } 857 858 #ifdef IPSEC 859 /* 860 * enforce IPsec policy checking if we are seeing last header. 861 * note that we do not visit this with protocols with pcb layer 862 * code - like udp/tcp/raw ip. 863 */ 864 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 && 865 ipsec4_in_reject(m, NULL)) { 866 ipsecstat.in_polvio++; 867 goto bad; 868 } 869 #endif 870 871 /* 872 * Switch out to protocol's input routine. 873 */ 874 #if IFA_STATS 875 if (ia && ip) 876 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len); 877 #endif 878 ipstat.ips_delivered++; 879 { 880 int off = hlen, nh = ip->ip_p; 881 882 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh); 883 return; 884 } 885 bad: 886 m_freem(m); 887 return; 888 889 badcsum: 890 ipstat.ips_badsum++; 891 m_freem(m); 892 } 893 894 /* 895 * Take incoming datagram fragment and try to 896 * reassemble it into whole datagram. If a chain for 897 * reassembly of this datagram already exists, then it 898 * is given as fp; otherwise have to make a chain. 899 */ 900 struct mbuf * 901 ip_reass(ipqe, fp) 902 struct ipqent *ipqe; 903 struct ipq *fp; 904 { 905 struct mbuf *m = ipqe->ipqe_m; 906 struct ipqent *nq, *p, *q; 907 struct ip *ip; 908 struct mbuf *t; 909 int hlen = ipqe->ipqe_ip->ip_hl << 2; 910 int i, next; 911 912 IPQ_LOCK_CHECK(); 913 914 /* 915 * Presence of header sizes in mbufs 916 * would confuse code below. 917 */ 918 m->m_data += hlen; 919 m->m_len -= hlen; 920 921 /* 922 * If first fragment to arrive, create a reassembly queue. 923 */ 924 if (fp == 0) { 925 /* 926 * Enforce upper bound on number of fragmented packets 927 * for which we attempt reassembly; 928 * If maxfrag is 0, never accept fragments. 929 * If maxfrag is -1, accept all fragments without limitation. 930 */ 931 if (ip_maxfragpackets < 0) 932 ; 933 else if (ip_nfragpackets >= ip_maxfragpackets) 934 goto dropfrag; 935 ip_nfragpackets++; 936 MALLOC(fp, struct ipq *, sizeof (struct ipq), 937 M_FTABLE, M_NOWAIT); 938 if (fp == NULL) 939 goto dropfrag; 940 LIST_INSERT_HEAD(&ipq, fp, ipq_q); 941 fp->ipq_ttl = IPFRAGTTL; 942 fp->ipq_p = ipqe->ipqe_ip->ip_p; 943 fp->ipq_id = ipqe->ipqe_ip->ip_id; 944 TAILQ_INIT(&fp->ipq_fragq); 945 fp->ipq_src = ipqe->ipqe_ip->ip_src; 946 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 947 p = NULL; 948 goto insert; 949 } 950 951 /* 952 * Find a segment which begins after this one does. 953 */ 954 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 955 p = q, q = TAILQ_NEXT(q, ipqe_q)) 956 if (ntohs(q->ipqe_ip->ip_off) > ntohs(ipqe->ipqe_ip->ip_off)) 957 break; 958 959 /* 960 * If there is a preceding segment, it may provide some of 961 * our data already. If so, drop the data from the incoming 962 * segment. If it provides all of our data, drop us. 963 */ 964 if (p != NULL) { 965 i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) - 966 ntohs(ipqe->ipqe_ip->ip_off); 967 if (i > 0) { 968 if (i >= ntohs(ipqe->ipqe_ip->ip_len)) 969 goto dropfrag; 970 m_adj(ipqe->ipqe_m, i); 971 ipqe->ipqe_ip->ip_off = 972 htons(ntohs(ipqe->ipqe_ip->ip_off) + i); 973 ipqe->ipqe_ip->ip_len = 974 htons(ntohs(ipqe->ipqe_ip->ip_len) - i); 975 } 976 } 977 978 /* 979 * While we overlap succeeding segments trim them or, 980 * if they are completely covered, dequeue them. 981 */ 982 for (; q != NULL && 983 ntohs(ipqe->ipqe_ip->ip_off) + ntohs(ipqe->ipqe_ip->ip_len) > 984 ntohs(q->ipqe_ip->ip_off); q = nq) { 985 i = (ntohs(ipqe->ipqe_ip->ip_off) + 986 ntohs(ipqe->ipqe_ip->ip_len)) - ntohs(q->ipqe_ip->ip_off); 987 if (i < ntohs(q->ipqe_ip->ip_len)) { 988 q->ipqe_ip->ip_len = 989 htons(ntohs(q->ipqe_ip->ip_len) - i); 990 q->ipqe_ip->ip_off = 991 htons(ntohs(q->ipqe_ip->ip_off) + i); 992 m_adj(q->ipqe_m, i); 993 break; 994 } 995 nq = TAILQ_NEXT(q, ipqe_q); 996 m_freem(q->ipqe_m); 997 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 998 pool_put(&ipqent_pool, q); 999 } 1000 1001 insert: 1002 /* 1003 * Stick new segment in its place; 1004 * check for complete reassembly. 1005 */ 1006 if (p == NULL) { 1007 TAILQ_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 1008 } else { 1009 TAILQ_INSERT_AFTER(&fp->ipq_fragq, p, ipqe, ipqe_q); 1010 } 1011 next = 0; 1012 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1013 p = q, q = TAILQ_NEXT(q, ipqe_q)) { 1014 if (ntohs(q->ipqe_ip->ip_off) != next) 1015 return (0); 1016 next += ntohs(q->ipqe_ip->ip_len); 1017 } 1018 if (p->ipqe_mff) 1019 return (0); 1020 1021 /* 1022 * Reassembly is complete. Check for a bogus message size and 1023 * concatenate fragments. 1024 */ 1025 q = TAILQ_FIRST(&fp->ipq_fragq); 1026 ip = q->ipqe_ip; 1027 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 1028 ipstat.ips_toolong++; 1029 ip_freef(fp); 1030 return (0); 1031 } 1032 m = q->ipqe_m; 1033 t = m->m_next; 1034 m->m_next = 0; 1035 m_cat(m, t); 1036 nq = TAILQ_NEXT(q, ipqe_q); 1037 pool_put(&ipqent_pool, q); 1038 for (q = nq; q != NULL; q = nq) { 1039 t = q->ipqe_m; 1040 nq = TAILQ_NEXT(q, ipqe_q); 1041 pool_put(&ipqent_pool, q); 1042 m_cat(m, t); 1043 } 1044 1045 /* 1046 * Create header for new ip packet by 1047 * modifying header of first packet; 1048 * dequeue and discard fragment reassembly header. 1049 * Make header visible. 1050 */ 1051 ip->ip_len = htons(next); 1052 ip->ip_src = fp->ipq_src; 1053 ip->ip_dst = fp->ipq_dst; 1054 LIST_REMOVE(fp, ipq_q); 1055 FREE(fp, M_FTABLE); 1056 ip_nfragpackets--; 1057 m->m_len += (ip->ip_hl << 2); 1058 m->m_data -= (ip->ip_hl << 2); 1059 /* some debugging cruft by sklower, below, will go away soon */ 1060 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 1061 int plen = 0; 1062 for (t = m; t; t = t->m_next) 1063 plen += t->m_len; 1064 m->m_pkthdr.len = plen; 1065 } 1066 return (m); 1067 1068 dropfrag: 1069 ipstat.ips_fragdropped++; 1070 m_freem(m); 1071 pool_put(&ipqent_pool, ipqe); 1072 return (0); 1073 } 1074 1075 /* 1076 * Free a fragment reassembly header and all 1077 * associated datagrams. 1078 */ 1079 void 1080 ip_freef(fp) 1081 struct ipq *fp; 1082 { 1083 struct ipqent *q, *p; 1084 1085 IPQ_LOCK_CHECK(); 1086 1087 for (q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; q = p) { 1088 p = TAILQ_NEXT(q, ipqe_q); 1089 m_freem(q->ipqe_m); 1090 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1091 pool_put(&ipqent_pool, q); 1092 } 1093 LIST_REMOVE(fp, ipq_q); 1094 FREE(fp, M_FTABLE); 1095 ip_nfragpackets--; 1096 } 1097 1098 /* 1099 * IP timer processing; 1100 * if a timer expires on a reassembly 1101 * queue, discard it. 1102 */ 1103 void 1104 ip_slowtimo() 1105 { 1106 struct ipq *fp, *nfp; 1107 int s = splsoftnet(); 1108 1109 IPQ_LOCK(); 1110 for (fp = LIST_FIRST(&ipq); fp != NULL; fp = nfp) { 1111 nfp = LIST_NEXT(fp, ipq_q); 1112 if (--fp->ipq_ttl == 0) { 1113 ipstat.ips_fragtimeout++; 1114 ip_freef(fp); 1115 } 1116 } 1117 /* 1118 * If we are over the maximum number of fragments 1119 * (due to the limit being lowered), drain off 1120 * enough to get down to the new limit. 1121 */ 1122 if (ip_maxfragpackets < 0) 1123 ; 1124 else { 1125 while (ip_nfragpackets > ip_maxfragpackets && LIST_FIRST(&ipq)) 1126 ip_freef(LIST_FIRST(&ipq)); 1127 } 1128 IPQ_UNLOCK(); 1129 #ifdef GATEWAY 1130 ipflow_slowtimo(); 1131 #endif 1132 splx(s); 1133 } 1134 1135 /* 1136 * Drain off all datagram fragments. 1137 */ 1138 void 1139 ip_drain() 1140 { 1141 1142 /* 1143 * We may be called from a device's interrupt context. If 1144 * the ipq is already busy, just bail out now. 1145 */ 1146 if (ipq_lock_try() == 0) 1147 return; 1148 1149 while (LIST_FIRST(&ipq) != NULL) { 1150 ipstat.ips_fragdropped++; 1151 ip_freef(LIST_FIRST(&ipq)); 1152 } 1153 1154 IPQ_UNLOCK(); 1155 } 1156 1157 /* 1158 * Do option processing on a datagram, 1159 * possibly discarding it if bad options are encountered, 1160 * or forwarding it if source-routed. 1161 * Returns 1 if packet has been forwarded/freed, 1162 * 0 if the packet should be processed further. 1163 */ 1164 int 1165 ip_dooptions(m) 1166 struct mbuf *m; 1167 { 1168 struct ip *ip = mtod(m, struct ip *); 1169 u_char *cp, *cp0; 1170 struct ip_timestamp *ipt; 1171 struct in_ifaddr *ia; 1172 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 1173 struct in_addr dst; 1174 n_time ntime; 1175 1176 dst = ip->ip_dst; 1177 cp = (u_char *)(ip + 1); 1178 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1179 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1180 opt = cp[IPOPT_OPTVAL]; 1181 if (opt == IPOPT_EOL) 1182 break; 1183 if (opt == IPOPT_NOP) 1184 optlen = 1; 1185 else { 1186 if (cnt < IPOPT_OLEN + sizeof(*cp)) { 1187 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1188 goto bad; 1189 } 1190 optlen = cp[IPOPT_OLEN]; 1191 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) { 1192 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1193 goto bad; 1194 } 1195 } 1196 switch (opt) { 1197 1198 default: 1199 break; 1200 1201 /* 1202 * Source routing with record. 1203 * Find interface with current destination address. 1204 * If none on this machine then drop if strictly routed, 1205 * or do nothing if loosely routed. 1206 * Record interface address and bring up next address 1207 * component. If strictly routed make sure next 1208 * address is on directly accessible net. 1209 */ 1210 case IPOPT_LSRR: 1211 case IPOPT_SSRR: 1212 if (ip_allowsrcrt == 0) { 1213 type = ICMP_UNREACH; 1214 code = ICMP_UNREACH_NET_PROHIB; 1215 goto bad; 1216 } 1217 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1218 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1219 goto bad; 1220 } 1221 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1222 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1223 goto bad; 1224 } 1225 ipaddr.sin_addr = ip->ip_dst; 1226 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1227 if (ia == 0) { 1228 if (opt == IPOPT_SSRR) { 1229 type = ICMP_UNREACH; 1230 code = ICMP_UNREACH_SRCFAIL; 1231 goto bad; 1232 } 1233 /* 1234 * Loose routing, and not at next destination 1235 * yet; nothing to do except forward. 1236 */ 1237 break; 1238 } 1239 off--; /* 0 origin */ 1240 if ((off + sizeof(struct in_addr)) > optlen) { 1241 /* 1242 * End of source route. Should be for us. 1243 */ 1244 save_rte(cp, ip->ip_src); 1245 break; 1246 } 1247 /* 1248 * locate outgoing interface 1249 */ 1250 bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr, 1251 sizeof(ipaddr.sin_addr)); 1252 if (opt == IPOPT_SSRR) 1253 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1254 else 1255 ia = ip_rtaddr(ipaddr.sin_addr); 1256 if (ia == 0) { 1257 type = ICMP_UNREACH; 1258 code = ICMP_UNREACH_SRCFAIL; 1259 goto bad; 1260 } 1261 ip->ip_dst = ipaddr.sin_addr; 1262 bcopy((caddr_t)&ia->ia_addr.sin_addr, 1263 (caddr_t)(cp + off), sizeof(struct in_addr)); 1264 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1265 /* 1266 * Let ip_intr's mcast routing check handle mcast pkts 1267 */ 1268 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 1269 break; 1270 1271 case IPOPT_RR: 1272 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1273 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1274 goto bad; 1275 } 1276 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1277 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1278 goto bad; 1279 } 1280 /* 1281 * If no space remains, ignore. 1282 */ 1283 off--; /* 0 origin */ 1284 if ((off + sizeof(struct in_addr)) > optlen) 1285 break; 1286 bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr, 1287 sizeof(ipaddr.sin_addr)); 1288 /* 1289 * locate outgoing interface; if we're the destination, 1290 * use the incoming interface (should be same). 1291 */ 1292 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))) 1293 == NULL && 1294 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) { 1295 type = ICMP_UNREACH; 1296 code = ICMP_UNREACH_HOST; 1297 goto bad; 1298 } 1299 bcopy((caddr_t)&ia->ia_addr.sin_addr, 1300 (caddr_t)(cp + off), sizeof(struct in_addr)); 1301 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1302 break; 1303 1304 case IPOPT_TS: 1305 code = cp - (u_char *)ip; 1306 ipt = (struct ip_timestamp *)cp; 1307 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) { 1308 code = (u_char *)&ipt->ipt_len - (u_char *)ip; 1309 goto bad; 1310 } 1311 if (ipt->ipt_ptr < 5) { 1312 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip; 1313 goto bad; 1314 } 1315 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 1316 if (++ipt->ipt_oflw == 0) { 1317 code = (u_char *)&ipt->ipt_ptr - 1318 (u_char *)ip; 1319 goto bad; 1320 } 1321 break; 1322 } 1323 cp0 = (cp + ipt->ipt_ptr - 1); 1324 switch (ipt->ipt_flg) { 1325 1326 case IPOPT_TS_TSONLY: 1327 break; 1328 1329 case IPOPT_TS_TSANDADDR: 1330 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1331 sizeof(struct in_addr) > ipt->ipt_len) { 1332 code = (u_char *)&ipt->ipt_ptr - 1333 (u_char *)ip; 1334 goto bad; 1335 } 1336 ipaddr.sin_addr = dst; 1337 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr), 1338 m->m_pkthdr.rcvif)); 1339 if (ia == 0) 1340 continue; 1341 bcopy(&ia->ia_addr.sin_addr, 1342 cp0, sizeof(struct in_addr)); 1343 ipt->ipt_ptr += sizeof(struct in_addr); 1344 break; 1345 1346 case IPOPT_TS_PRESPEC: 1347 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1348 sizeof(struct in_addr) > ipt->ipt_len) { 1349 code = (u_char *)&ipt->ipt_ptr - 1350 (u_char *)ip; 1351 goto bad; 1352 } 1353 bcopy(cp0, &ipaddr.sin_addr, 1354 sizeof(struct in_addr)); 1355 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))) 1356 == NULL) 1357 continue; 1358 ipt->ipt_ptr += sizeof(struct in_addr); 1359 break; 1360 1361 default: 1362 /* XXX can't take &ipt->ipt_flg */ 1363 code = (u_char *)&ipt->ipt_ptr - 1364 (u_char *)ip + 1; 1365 goto bad; 1366 } 1367 ntime = iptime(); 1368 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */ 1369 bcopy(cp0, (caddr_t)cp + ipt->ipt_ptr - 1, 1370 sizeof(n_time)); 1371 ipt->ipt_ptr += sizeof(n_time); 1372 } 1373 } 1374 if (forward) { 1375 if (ip_forwsrcrt == 0) { 1376 type = ICMP_UNREACH; 1377 code = ICMP_UNREACH_SRCFAIL; 1378 goto bad; 1379 } 1380 ip_forward(m, 1); 1381 return (1); 1382 } 1383 return (0); 1384 bad: 1385 icmp_error(m, type, code, 0, 0); 1386 ipstat.ips_badoptions++; 1387 return (1); 1388 } 1389 1390 /* 1391 * Given address of next destination (final or next hop), 1392 * return internet address info of interface to be used to get there. 1393 */ 1394 struct in_ifaddr * 1395 ip_rtaddr(dst) 1396 struct in_addr dst; 1397 { 1398 struct sockaddr_in *sin; 1399 1400 sin = satosin(&ipforward_rt.ro_dst); 1401 1402 if (ipforward_rt.ro_rt == 0 || !in_hosteq(dst, sin->sin_addr)) { 1403 if (ipforward_rt.ro_rt) { 1404 RTFREE(ipforward_rt.ro_rt); 1405 ipforward_rt.ro_rt = 0; 1406 } 1407 sin->sin_family = AF_INET; 1408 sin->sin_len = sizeof(*sin); 1409 sin->sin_addr = dst; 1410 1411 rtalloc(&ipforward_rt); 1412 } 1413 if (ipforward_rt.ro_rt == 0) 1414 return ((struct in_ifaddr *)0); 1415 return (ifatoia(ipforward_rt.ro_rt->rt_ifa)); 1416 } 1417 1418 /* 1419 * Save incoming source route for use in replies, 1420 * to be picked up later by ip_srcroute if the receiver is interested. 1421 */ 1422 void 1423 save_rte(option, dst) 1424 u_char *option; 1425 struct in_addr dst; 1426 { 1427 unsigned olen; 1428 1429 olen = option[IPOPT_OLEN]; 1430 #ifdef DIAGNOSTIC 1431 if (ipprintfs) 1432 printf("save_rte: olen %d\n", olen); 1433 #endif /* 0 */ 1434 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1435 return; 1436 bcopy((caddr_t)option, (caddr_t)ip_srcrt.srcopt, olen); 1437 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1438 ip_srcrt.dst = dst; 1439 } 1440 1441 /* 1442 * Retrieve incoming source route for use in replies, 1443 * in the same form used by setsockopt. 1444 * The first hop is placed before the options, will be removed later. 1445 */ 1446 struct mbuf * 1447 ip_srcroute() 1448 { 1449 struct in_addr *p, *q; 1450 struct mbuf *m; 1451 1452 if (ip_nhops == 0) 1453 return ((struct mbuf *)0); 1454 m = m_get(M_DONTWAIT, MT_SOOPTS); 1455 if (m == 0) 1456 return ((struct mbuf *)0); 1457 1458 MCLAIM(m, &inetdomain.dom_mowner); 1459 #define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1460 1461 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1462 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1463 OPTSIZ; 1464 #ifdef DIAGNOSTIC 1465 if (ipprintfs) 1466 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1467 #endif 1468 1469 /* 1470 * First save first hop for return route 1471 */ 1472 p = &ip_srcrt.route[ip_nhops - 1]; 1473 *(mtod(m, struct in_addr *)) = *p--; 1474 #ifdef DIAGNOSTIC 1475 if (ipprintfs) 1476 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1477 #endif 1478 1479 /* 1480 * Copy option fields and padding (nop) to mbuf. 1481 */ 1482 ip_srcrt.nop = IPOPT_NOP; 1483 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1484 bcopy((caddr_t)&ip_srcrt.nop, 1485 mtod(m, caddr_t) + sizeof(struct in_addr), OPTSIZ); 1486 q = (struct in_addr *)(mtod(m, caddr_t) + 1487 sizeof(struct in_addr) + OPTSIZ); 1488 #undef OPTSIZ 1489 /* 1490 * Record return path as an IP source route, 1491 * reversing the path (pointers are now aligned). 1492 */ 1493 while (p >= ip_srcrt.route) { 1494 #ifdef DIAGNOSTIC 1495 if (ipprintfs) 1496 printf(" %x", ntohl(q->s_addr)); 1497 #endif 1498 *q++ = *p--; 1499 } 1500 /* 1501 * Last hop goes to final destination. 1502 */ 1503 *q = ip_srcrt.dst; 1504 #ifdef DIAGNOSTIC 1505 if (ipprintfs) 1506 printf(" %x\n", ntohl(q->s_addr)); 1507 #endif 1508 return (m); 1509 } 1510 1511 /* 1512 * Strip out IP options, at higher 1513 * level protocol in the kernel. 1514 * Second argument is buffer to which options 1515 * will be moved, and return value is their length. 1516 * XXX should be deleted; last arg currently ignored. 1517 */ 1518 void 1519 ip_stripoptions(m, mopt) 1520 struct mbuf *m; 1521 struct mbuf *mopt; 1522 { 1523 int i; 1524 struct ip *ip = mtod(m, struct ip *); 1525 caddr_t opts; 1526 int olen; 1527 1528 olen = (ip->ip_hl << 2) - sizeof (struct ip); 1529 opts = (caddr_t)(ip + 1); 1530 i = m->m_len - (sizeof (struct ip) + olen); 1531 bcopy(opts + olen, opts, (unsigned)i); 1532 m->m_len -= olen; 1533 if (m->m_flags & M_PKTHDR) 1534 m->m_pkthdr.len -= olen; 1535 ip->ip_len = htons(ntohs(ip->ip_len) - olen); 1536 ip->ip_hl = sizeof (struct ip) >> 2; 1537 } 1538 1539 const int inetctlerrmap[PRC_NCMDS] = { 1540 0, 0, 0, 0, 1541 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1542 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1543 EMSGSIZE, EHOSTUNREACH, 0, 0, 1544 0, 0, 0, 0, 1545 ENOPROTOOPT 1546 }; 1547 1548 /* 1549 * Forward a packet. If some error occurs return the sender 1550 * an icmp packet. Note we can't always generate a meaningful 1551 * icmp message because icmp doesn't have a large enough repertoire 1552 * of codes and types. 1553 * 1554 * If not forwarding, just drop the packet. This could be confusing 1555 * if ipforwarding was zero but some routing protocol was advancing 1556 * us as a gateway to somewhere. However, we must let the routing 1557 * protocol deal with that. 1558 * 1559 * The srcrt parameter indicates whether the packet is being forwarded 1560 * via a source route. 1561 */ 1562 void 1563 ip_forward(m, srcrt) 1564 struct mbuf *m; 1565 int srcrt; 1566 { 1567 struct ip *ip = mtod(m, struct ip *); 1568 struct sockaddr_in *sin; 1569 struct rtentry *rt; 1570 int error, type = 0, code = 0; 1571 struct mbuf *mcopy; 1572 n_long dest; 1573 struct ifnet *destifp; 1574 #ifdef IPSEC 1575 struct ifnet dummyifp; 1576 #endif 1577 1578 /* 1579 * We are now in the output path. 1580 */ 1581 MCLAIM(m, &ip_tx_mowner); 1582 1583 /* 1584 * Clear any in-bound checksum flags for this packet. 1585 */ 1586 m->m_pkthdr.csum_flags = 0; 1587 1588 dest = 0; 1589 #ifdef DIAGNOSTIC 1590 if (ipprintfs) 1591 printf("forward: src %2.2x dst %2.2x ttl %x\n", 1592 ntohl(ip->ip_src.s_addr), 1593 ntohl(ip->ip_dst.s_addr), ip->ip_ttl); 1594 #endif 1595 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) { 1596 ipstat.ips_cantforward++; 1597 m_freem(m); 1598 return; 1599 } 1600 if (ip->ip_ttl <= IPTTLDEC) { 1601 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1602 return; 1603 } 1604 ip->ip_ttl -= IPTTLDEC; 1605 1606 sin = satosin(&ipforward_rt.ro_dst); 1607 if ((rt = ipforward_rt.ro_rt) == 0 || 1608 !in_hosteq(ip->ip_dst, sin->sin_addr)) { 1609 if (ipforward_rt.ro_rt) { 1610 RTFREE(ipforward_rt.ro_rt); 1611 ipforward_rt.ro_rt = 0; 1612 } 1613 sin->sin_family = AF_INET; 1614 sin->sin_len = sizeof(struct sockaddr_in); 1615 sin->sin_addr = ip->ip_dst; 1616 1617 rtalloc(&ipforward_rt); 1618 if (ipforward_rt.ro_rt == 0) { 1619 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0); 1620 return; 1621 } 1622 rt = ipforward_rt.ro_rt; 1623 } 1624 1625 /* 1626 * Save at most 68 bytes of the packet in case 1627 * we need to generate an ICMP message to the src. 1628 * Pullup to avoid sharing mbuf cluster between m and mcopy. 1629 */ 1630 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT); 1631 if (mcopy) 1632 mcopy = m_pullup(mcopy, ip->ip_hl << 2); 1633 1634 /* 1635 * If forwarding packet using same interface that it came in on, 1636 * perhaps should send a redirect to sender to shortcut a hop. 1637 * Only send redirect if source is sending directly to us, 1638 * and if packet was not source routed (or has any options). 1639 * Also, don't send redirect if forwarding using a default route 1640 * or a route modified by a redirect. 1641 */ 1642 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1643 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1644 !in_nullhost(satosin(rt_key(rt))->sin_addr) && 1645 ipsendredirects && !srcrt) { 1646 if (rt->rt_ifa && 1647 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1648 ifatoia(rt->rt_ifa)->ia_subnet) { 1649 if (rt->rt_flags & RTF_GATEWAY) 1650 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1651 else 1652 dest = ip->ip_dst.s_addr; 1653 /* 1654 * Router requirements says to only send host 1655 * redirects. 1656 */ 1657 type = ICMP_REDIRECT; 1658 code = ICMP_REDIRECT_HOST; 1659 #ifdef DIAGNOSTIC 1660 if (ipprintfs) 1661 printf("redirect (%d) to %x\n", code, 1662 (u_int32_t)dest); 1663 #endif 1664 } 1665 } 1666 1667 #ifdef IPSEC 1668 /* Don't lookup socket in forwarding case */ 1669 (void)ipsec_setsocket(m, NULL); 1670 #endif 1671 error = ip_output(m, (struct mbuf *)0, &ipforward_rt, 1672 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 0); 1673 if (error) 1674 ipstat.ips_cantforward++; 1675 else { 1676 ipstat.ips_forward++; 1677 if (type) 1678 ipstat.ips_redirectsent++; 1679 else { 1680 if (mcopy) { 1681 #ifdef GATEWAY 1682 if (mcopy->m_flags & M_CANFASTFWD) 1683 ipflow_create(&ipforward_rt, mcopy); 1684 #endif 1685 m_freem(mcopy); 1686 } 1687 return; 1688 } 1689 } 1690 if (mcopy == NULL) 1691 return; 1692 destifp = NULL; 1693 1694 switch (error) { 1695 1696 case 0: /* forwarded, but need redirect */ 1697 /* type, code set above */ 1698 break; 1699 1700 case ENETUNREACH: /* shouldn't happen, checked above */ 1701 case EHOSTUNREACH: 1702 case ENETDOWN: 1703 case EHOSTDOWN: 1704 default: 1705 type = ICMP_UNREACH; 1706 code = ICMP_UNREACH_HOST; 1707 break; 1708 1709 case EMSGSIZE: 1710 type = ICMP_UNREACH; 1711 code = ICMP_UNREACH_NEEDFRAG; 1712 #ifndef IPSEC 1713 if (ipforward_rt.ro_rt) 1714 destifp = ipforward_rt.ro_rt->rt_ifp; 1715 #else 1716 /* 1717 * If the packet is routed over IPsec tunnel, tell the 1718 * originator the tunnel MTU. 1719 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 1720 * XXX quickhack!!! 1721 */ 1722 if (ipforward_rt.ro_rt) { 1723 struct secpolicy *sp; 1724 int ipsecerror; 1725 size_t ipsechdr; 1726 struct route *ro; 1727 1728 sp = ipsec4_getpolicybyaddr(mcopy, 1729 IPSEC_DIR_OUTBOUND, IP_FORWARDING, 1730 &ipsecerror); 1731 1732 if (sp == NULL) 1733 destifp = ipforward_rt.ro_rt->rt_ifp; 1734 else { 1735 /* count IPsec header size */ 1736 ipsechdr = ipsec4_hdrsiz(mcopy, 1737 IPSEC_DIR_OUTBOUND, NULL); 1738 1739 /* 1740 * find the correct route for outer IPv4 1741 * header, compute tunnel MTU. 1742 * 1743 * XXX BUG ALERT 1744 * The "dummyifp" code relies upon the fact 1745 * that icmp_error() touches only ifp->if_mtu. 1746 */ 1747 /*XXX*/ 1748 destifp = NULL; 1749 if (sp->req != NULL 1750 && sp->req->sav != NULL 1751 && sp->req->sav->sah != NULL) { 1752 ro = &sp->req->sav->sah->sa_route; 1753 if (ro->ro_rt && ro->ro_rt->rt_ifp) { 1754 dummyifp.if_mtu = 1755 ro->ro_rt->rt_rmx.rmx_mtu ? 1756 ro->ro_rt->rt_rmx.rmx_mtu : 1757 ro->ro_rt->rt_ifp->if_mtu; 1758 dummyifp.if_mtu -= ipsechdr; 1759 destifp = &dummyifp; 1760 } 1761 } 1762 1763 key_freesp(sp); 1764 } 1765 } 1766 #endif /*IPSEC*/ 1767 ipstat.ips_cantfrag++; 1768 break; 1769 1770 case ENOBUFS: 1771 #if 1 1772 /* 1773 * a router should not generate ICMP_SOURCEQUENCH as 1774 * required in RFC1812 Requirements for IP Version 4 Routers. 1775 * source quench could be a big problem under DoS attacks, 1776 * or if the underlying interface is rate-limited. 1777 */ 1778 if (mcopy) 1779 m_freem(mcopy); 1780 return; 1781 #else 1782 type = ICMP_SOURCEQUENCH; 1783 code = 0; 1784 break; 1785 #endif 1786 } 1787 icmp_error(mcopy, type, code, dest, destifp); 1788 } 1789 1790 void 1791 ip_savecontrol(inp, mp, ip, m) 1792 struct inpcb *inp; 1793 struct mbuf **mp; 1794 struct ip *ip; 1795 struct mbuf *m; 1796 { 1797 1798 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 1799 struct timeval tv; 1800 1801 microtime(&tv); 1802 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1803 SCM_TIMESTAMP, SOL_SOCKET); 1804 if (*mp) 1805 mp = &(*mp)->m_next; 1806 } 1807 if (inp->inp_flags & INP_RECVDSTADDR) { 1808 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst, 1809 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 1810 if (*mp) 1811 mp = &(*mp)->m_next; 1812 } 1813 #ifdef notyet 1814 /* 1815 * XXX 1816 * Moving these out of udp_input() made them even more broken 1817 * than they already were. 1818 * - fenner@parc.xerox.com 1819 */ 1820 /* options were tossed already */ 1821 if (inp->inp_flags & INP_RECVOPTS) { 1822 *mp = sbcreatecontrol((caddr_t) opts_deleted_above, 1823 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 1824 if (*mp) 1825 mp = &(*mp)->m_next; 1826 } 1827 /* ip_srcroute doesn't do what we want here, need to fix */ 1828 if (inp->inp_flags & INP_RECVRETOPTS) { 1829 *mp = sbcreatecontrol((caddr_t) ip_srcroute(), 1830 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 1831 if (*mp) 1832 mp = &(*mp)->m_next; 1833 } 1834 #endif 1835 if (inp->inp_flags & INP_RECVIF) { 1836 struct sockaddr_dl sdl; 1837 1838 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]); 1839 sdl.sdl_family = AF_LINK; 1840 sdl.sdl_index = m->m_pkthdr.rcvif ? 1841 m->m_pkthdr.rcvif->if_index : 0; 1842 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0; 1843 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len, 1844 IP_RECVIF, IPPROTO_IP); 1845 if (*mp) 1846 mp = &(*mp)->m_next; 1847 } 1848 } 1849 1850 int 1851 ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 1852 int *name; 1853 u_int namelen; 1854 void *oldp; 1855 size_t *oldlenp; 1856 void *newp; 1857 size_t newlen; 1858 { 1859 extern int subnetsarelocal, hostzeroisbroadcast; 1860 1861 int error, old; 1862 1863 /* All sysctl names at this level are terminal. */ 1864 if (namelen != 1) 1865 return (ENOTDIR); 1866 1867 switch (name[0]) { 1868 case IPCTL_FORWARDING: 1869 return (sysctl_int(oldp, oldlenp, newp, newlen, &ipforwarding)); 1870 case IPCTL_SENDREDIRECTS: 1871 return (sysctl_int(oldp, oldlenp, newp, newlen, 1872 &ipsendredirects)); 1873 case IPCTL_DEFTTL: 1874 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_defttl)); 1875 #ifdef notyet 1876 case IPCTL_DEFMTU: 1877 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu)); 1878 #endif 1879 case IPCTL_FORWSRCRT: 1880 /* Don't allow this to change in a secure environment. */ 1881 if (securelevel > 0) 1882 return (sysctl_rdint(oldp, oldlenp, newp, 1883 ip_forwsrcrt)); 1884 else 1885 return (sysctl_int(oldp, oldlenp, newp, newlen, 1886 &ip_forwsrcrt)); 1887 case IPCTL_DIRECTEDBCAST: 1888 return (sysctl_int(oldp, oldlenp, newp, newlen, 1889 &ip_directedbcast)); 1890 case IPCTL_ALLOWSRCRT: 1891 return (sysctl_int(oldp, oldlenp, newp, newlen, 1892 &ip_allowsrcrt)); 1893 case IPCTL_SUBNETSARELOCAL: 1894 return (sysctl_int(oldp, oldlenp, newp, newlen, 1895 &subnetsarelocal)); 1896 case IPCTL_MTUDISC: 1897 error = sysctl_int(oldp, oldlenp, newp, newlen, 1898 &ip_mtudisc); 1899 if (error == 0 && ip_mtudisc == 0) 1900 rt_timer_queue_remove_all(ip_mtudisc_timeout_q, TRUE); 1901 return error; 1902 case IPCTL_ANONPORTMIN: 1903 old = anonportmin; 1904 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmin); 1905 if (anonportmin >= anonportmax || anonportmin < 0 1906 || anonportmin > 65535 1907 #ifndef IPNOPRIVPORTS 1908 || anonportmin < IPPORT_RESERVED 1909 #endif 1910 ) { 1911 anonportmin = old; 1912 return (EINVAL); 1913 } 1914 return (error); 1915 case IPCTL_ANONPORTMAX: 1916 old = anonportmax; 1917 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmax); 1918 if (anonportmin >= anonportmax || anonportmax < 0 1919 || anonportmax > 65535 1920 #ifndef IPNOPRIVPORTS 1921 || anonportmax < IPPORT_RESERVED 1922 #endif 1923 ) { 1924 anonportmax = old; 1925 return (EINVAL); 1926 } 1927 return (error); 1928 case IPCTL_MTUDISCTIMEOUT: 1929 old = ip_mtudisc_timeout; 1930 error = sysctl_int(oldp, oldlenp, newp, newlen, 1931 &ip_mtudisc_timeout); 1932 if (ip_mtudisc_timeout < 0) { 1933 ip_mtudisc_timeout = old; 1934 return (EINVAL); 1935 } 1936 if (error == 0) 1937 rt_timer_queue_change(ip_mtudisc_timeout_q, 1938 ip_mtudisc_timeout); 1939 return (error); 1940 #ifdef GATEWAY 1941 case IPCTL_MAXFLOWS: 1942 { 1943 int s; 1944 1945 error = sysctl_int(oldp, oldlenp, newp, newlen, 1946 &ip_maxflows); 1947 s = splsoftnet(); 1948 ipflow_reap(0); 1949 splx(s); 1950 return (error); 1951 } 1952 #endif 1953 case IPCTL_HOSTZEROBROADCAST: 1954 return (sysctl_int(oldp, oldlenp, newp, newlen, 1955 &hostzeroisbroadcast)); 1956 #if NGIF > 0 1957 case IPCTL_GIF_TTL: 1958 return (sysctl_int(oldp, oldlenp, newp, newlen, 1959 &ip_gif_ttl)); 1960 #endif 1961 1962 #if NGRE > 0 1963 case IPCTL_GRE_TTL: 1964 return (sysctl_int(oldp, oldlenp, newp, newlen, 1965 &ip_gre_ttl)); 1966 #endif 1967 1968 #ifndef IPNOPRIVPORTS 1969 case IPCTL_LOWPORTMIN: 1970 old = lowportmin; 1971 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmin); 1972 if (lowportmin >= lowportmax 1973 || lowportmin > IPPORT_RESERVEDMAX 1974 || lowportmin < IPPORT_RESERVEDMIN 1975 ) { 1976 lowportmin = old; 1977 return (EINVAL); 1978 } 1979 return (error); 1980 case IPCTL_LOWPORTMAX: 1981 old = lowportmax; 1982 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmax); 1983 if (lowportmin >= lowportmax 1984 || lowportmax > IPPORT_RESERVEDMAX 1985 || lowportmax < IPPORT_RESERVEDMIN 1986 ) { 1987 lowportmax = old; 1988 return (EINVAL); 1989 } 1990 return (error); 1991 #endif 1992 1993 case IPCTL_MAXFRAGPACKETS: 1994 return (sysctl_int(oldp, oldlenp, newp, newlen, 1995 &ip_maxfragpackets)); 1996 1997 case IPCTL_CHECKINTERFACE: 1998 return (sysctl_int(oldp, oldlenp, newp, newlen, 1999 &ip_checkinterface)); 2000 default: 2001 return (EOPNOTSUPP); 2002 } 2003 /* NOTREACHED */ 2004 } 2005