ip_input.c revision 1.181
1 /* $NetBSD: ip_input.c,v 1.181 2003/11/11 20:25:26 jonathan Exp $ */ 2 3 /* 4 * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the project nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 */ 31 32 /*- 33 * Copyright (c) 1998 The NetBSD Foundation, Inc. 34 * All rights reserved. 35 * 36 * This code is derived from software contributed to The NetBSD Foundation 37 * by Public Access Networks Corporation ("Panix"). It was developed under 38 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon. 39 * 40 * Redistribution and use in source and binary forms, with or without 41 * modification, are permitted provided that the following conditions 42 * are met: 43 * 1. Redistributions of source code must retain the above copyright 44 * notice, this list of conditions and the following disclaimer. 45 * 2. Redistributions in binary form must reproduce the above copyright 46 * notice, this list of conditions and the following disclaimer in the 47 * documentation and/or other materials provided with the distribution. 48 * 3. All advertising materials mentioning features or use of this software 49 * must display the following acknowledgement: 50 * This product includes software developed by the NetBSD 51 * Foundation, Inc. and its contributors. 52 * 4. Neither the name of The NetBSD Foundation nor the names of its 53 * contributors may be used to endorse or promote products derived 54 * from this software without specific prior written permission. 55 * 56 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 57 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 58 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 59 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 60 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 61 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 62 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 63 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 64 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 65 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 66 * POSSIBILITY OF SUCH DAMAGE. 67 */ 68 69 /* 70 * Copyright (c) 1982, 1986, 1988, 1993 71 * The Regents of the University of California. All rights reserved. 72 * 73 * Redistribution and use in source and binary forms, with or without 74 * modification, are permitted provided that the following conditions 75 * are met: 76 * 1. Redistributions of source code must retain the above copyright 77 * notice, this list of conditions and the following disclaimer. 78 * 2. Redistributions in binary form must reproduce the above copyright 79 * notice, this list of conditions and the following disclaimer in the 80 * documentation and/or other materials provided with the distribution. 81 * 3. Neither the name of the University nor the names of its contributors 82 * may be used to endorse or promote products derived from this software 83 * without specific prior written permission. 84 * 85 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 86 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 87 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 88 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 89 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 90 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 91 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 92 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 93 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 94 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 95 * SUCH DAMAGE. 96 * 97 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 98 */ 99 100 #include <sys/cdefs.h> 101 __KERNEL_RCSID(0, "$NetBSD: ip_input.c,v 1.181 2003/11/11 20:25:26 jonathan Exp $"); 102 103 #include "opt_gateway.h" 104 #include "opt_pfil_hooks.h" 105 #include "opt_ipsec.h" 106 #include "opt_mrouting.h" 107 #include "opt_mbuftrace.h" 108 #include "opt_inet_csum.h" 109 110 #include <sys/param.h> 111 #include <sys/systm.h> 112 #include <sys/malloc.h> 113 #include <sys/mbuf.h> 114 #include <sys/domain.h> 115 #include <sys/protosw.h> 116 #include <sys/socket.h> 117 #include <sys/socketvar.h> 118 #include <sys/errno.h> 119 #include <sys/time.h> 120 #include <sys/kernel.h> 121 #include <sys/pool.h> 122 #include <sys/sysctl.h> 123 124 #include <net/if.h> 125 #include <net/if_dl.h> 126 #include <net/route.h> 127 #include <net/pfil.h> 128 129 #include <netinet/in.h> 130 #include <netinet/in_systm.h> 131 #include <netinet/ip.h> 132 #include <netinet/in_pcb.h> 133 #include <netinet/in_var.h> 134 #include <netinet/ip_var.h> 135 #include <netinet/ip_icmp.h> 136 /* just for gif_ttl */ 137 #include <netinet/in_gif.h> 138 #include "gif.h" 139 #include <net/if_gre.h> 140 #include "gre.h" 141 142 #ifdef MROUTING 143 #include <netinet/ip_mroute.h> 144 #endif 145 146 #ifdef IPSEC 147 #include <netinet6/ipsec.h> 148 #include <netkey/key.h> 149 #endif 150 #ifdef FAST_IPSEC 151 #include <netipsec/ipsec.h> 152 #include <netipsec/key.h> 153 #endif /* FAST_IPSEC*/ 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_ifaddrhead; 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_multihashhead *in_multihashtbl; 227 struct ifqueue ipintrq; 228 struct ipstat ipstat; 229 230 #ifdef PFIL_HOOKS 231 struct pfil_head inet_pfil_hook; 232 #endif 233 234 struct ipqhead ipq; 235 int ipq_locked; 236 int ip_nfragpackets = 0; 237 int ip_maxfragpackets = 200; 238 239 static __inline int ipq_lock_try __P((void)); 240 static __inline void ipq_unlock __P((void)); 241 242 static __inline int 243 ipq_lock_try() 244 { 245 int s; 246 247 /* 248 * Use splvm() -- we're blocking things that would cause 249 * mbuf allocation. 250 */ 251 s = splvm(); 252 if (ipq_locked) { 253 splx(s); 254 return (0); 255 } 256 ipq_locked = 1; 257 splx(s); 258 return (1); 259 } 260 261 static __inline void 262 ipq_unlock() 263 { 264 int s; 265 266 s = splvm(); 267 ipq_locked = 0; 268 splx(s); 269 } 270 271 #ifdef DIAGNOSTIC 272 #define IPQ_LOCK() \ 273 do { \ 274 if (ipq_lock_try() == 0) { \ 275 printf("%s:%d: ipq already locked\n", __FILE__, __LINE__); \ 276 panic("ipq_lock"); \ 277 } \ 278 } while (/*CONSTCOND*/ 0) 279 #define IPQ_LOCK_CHECK() \ 280 do { \ 281 if (ipq_locked == 0) { \ 282 printf("%s:%d: ipq lock not held\n", __FILE__, __LINE__); \ 283 panic("ipq lock check"); \ 284 } \ 285 } while (/*CONSTCOND*/ 0) 286 #else 287 #define IPQ_LOCK() (void) ipq_lock_try() 288 #define IPQ_LOCK_CHECK() /* nothing */ 289 #endif 290 291 #define IPQ_UNLOCK() ipq_unlock() 292 293 struct pool inmulti_pool; 294 struct pool ipqent_pool; 295 296 #ifdef INET_CSUM_COUNTERS 297 #include <sys/device.h> 298 299 struct evcnt ip_hwcsum_bad = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 300 NULL, "inet", "hwcsum bad"); 301 struct evcnt ip_hwcsum_ok = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 302 NULL, "inet", "hwcsum ok"); 303 struct evcnt ip_swcsum = EVCNT_INITIALIZER(EVCNT_TYPE_MISC, 304 NULL, "inet", "swcsum"); 305 306 #define INET_CSUM_COUNTER_INCR(ev) (ev)->ev_count++ 307 308 #else 309 310 #define INET_CSUM_COUNTER_INCR(ev) /* nothing */ 311 312 #endif /* INET_CSUM_COUNTERS */ 313 314 /* 315 * We need to save the IP options in case a protocol wants to respond 316 * to an incoming packet over the same route if the packet got here 317 * using IP source routing. This allows connection establishment and 318 * maintenance when the remote end is on a network that is not known 319 * to us. 320 */ 321 int ip_nhops = 0; 322 static struct ip_srcrt { 323 struct in_addr dst; /* final destination */ 324 char nop; /* one NOP to align */ 325 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */ 326 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)]; 327 } ip_srcrt; 328 329 static void save_rte __P((u_char *, struct in_addr)); 330 331 #ifdef MBUFTRACE 332 struct mowner ip_rx_mowner = { "internet", "rx" }; 333 struct mowner ip_tx_mowner = { "internet", "tx" }; 334 #endif 335 336 /* 337 * IP initialization: fill in IP protocol switch table. 338 * All protocols not implemented in kernel go to raw IP protocol handler. 339 */ 340 void 341 ip_init() 342 { 343 struct protosw *pr; 344 int i; 345 346 pool_init(&inmulti_pool, sizeof(struct in_multi), 0, 0, 0, "inmltpl", 347 NULL); 348 pool_init(&ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl", 349 NULL); 350 351 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); 352 if (pr == 0) 353 panic("ip_init"); 354 for (i = 0; i < IPPROTO_MAX; i++) 355 ip_protox[i] = pr - inetsw; 356 for (pr = inetdomain.dom_protosw; 357 pr < inetdomain.dom_protoswNPROTOSW; pr++) 358 if (pr->pr_domain->dom_family == PF_INET && 359 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 360 ip_protox[pr->pr_protocol] = pr - inetsw; 361 LIST_INIT(&ipq); 362 ipintrq.ifq_maxlen = ipqmaxlen; 363 TAILQ_INIT(&in_ifaddrhead); 364 in_ifaddrhashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IFADDR, 365 M_WAITOK, &in_ifaddrhash); 366 in_multihashtbl = hashinit(IN_IFADDR_HASH_SIZE, HASH_LIST, M_IPMADDR, 367 M_WAITOK, &in_multihash); 368 ip_mtudisc_timeout_q = rt_timer_queue_create(ip_mtudisc_timeout); 369 #ifdef GATEWAY 370 ipflow_init(); 371 #endif 372 373 #ifdef PFIL_HOOKS 374 /* Register our Packet Filter hook. */ 375 inet_pfil_hook.ph_type = PFIL_TYPE_AF; 376 inet_pfil_hook.ph_af = AF_INET; 377 i = pfil_head_register(&inet_pfil_hook); 378 if (i != 0) 379 printf("ip_init: WARNING: unable to register pfil hook, " 380 "error %d\n", i); 381 #endif /* PFIL_HOOKS */ 382 383 #ifdef INET_CSUM_COUNTERS 384 evcnt_attach_static(&ip_hwcsum_bad); 385 evcnt_attach_static(&ip_hwcsum_ok); 386 evcnt_attach_static(&ip_swcsum); 387 #endif /* INET_CSUM_COUNTERS */ 388 389 #ifdef MBUFTRACE 390 MOWNER_ATTACH(&ip_tx_mowner); 391 MOWNER_ATTACH(&ip_rx_mowner); 392 #endif /* MBUFTRACE */ 393 } 394 395 struct sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET }; 396 struct route ipforward_rt; 397 398 /* 399 * IP software interrupt routine 400 */ 401 void 402 ipintr() 403 { 404 int s; 405 struct mbuf *m; 406 407 while (1) { 408 s = splnet(); 409 IF_DEQUEUE(&ipintrq, m); 410 splx(s); 411 if (m == 0) 412 return; 413 MCLAIM(m, &ip_rx_mowner); 414 ip_input(m); 415 } 416 } 417 418 /* 419 * Ip input routine. Checksum and byte swap header. If fragmented 420 * try to reassemble. Process options. Pass to next level. 421 */ 422 void 423 ip_input(struct mbuf *m) 424 { 425 struct ip *ip = NULL; 426 struct ipq *fp; 427 struct in_ifaddr *ia; 428 struct ifaddr *ifa; 429 struct ipqent *ipqe; 430 int hlen = 0, mff, len; 431 int downmatch; 432 int checkif; 433 int srcrt = 0; 434 #ifdef FAST_IPSEC 435 struct m_tag *mtag; 436 struct tdb_ident *tdbi; 437 struct secpolicy *sp; 438 int s, error; 439 #endif /* FAST_IPSEC */ 440 441 MCLAIM(m, &ip_rx_mowner); 442 #ifdef DIAGNOSTIC 443 if ((m->m_flags & M_PKTHDR) == 0) 444 panic("ipintr no HDR"); 445 #endif 446 447 /* 448 * If no IP addresses have been set yet but the interfaces 449 * are receiving, can't do anything with incoming packets yet. 450 */ 451 if (TAILQ_FIRST(&in_ifaddrhead) == 0) 452 goto bad; 453 ipstat.ips_total++; 454 /* 455 * If the IP header is not aligned, slurp it up into a new 456 * mbuf with space for link headers, in the event we forward 457 * it. Otherwise, if it is aligned, make sure the entire 458 * base IP header is in the first mbuf of the chain. 459 */ 460 if (IP_HDR_ALIGNED_P(mtod(m, caddr_t)) == 0) { 461 if ((m = m_copyup(m, sizeof(struct ip), 462 (max_linkhdr + 3) & ~3)) == NULL) { 463 /* XXXJRT new stat, please */ 464 ipstat.ips_toosmall++; 465 return; 466 } 467 } else if (__predict_false(m->m_len < sizeof (struct ip))) { 468 if ((m = m_pullup(m, sizeof (struct ip))) == NULL) { 469 ipstat.ips_toosmall++; 470 return; 471 } 472 } 473 ip = mtod(m, struct ip *); 474 if (ip->ip_v != IPVERSION) { 475 ipstat.ips_badvers++; 476 goto bad; 477 } 478 hlen = ip->ip_hl << 2; 479 if (hlen < sizeof(struct ip)) { /* minimum header length */ 480 ipstat.ips_badhlen++; 481 goto bad; 482 } 483 if (hlen > m->m_len) { 484 if ((m = m_pullup(m, hlen)) == 0) { 485 ipstat.ips_badhlen++; 486 return; 487 } 488 ip = mtod(m, struct ip *); 489 } 490 491 /* 492 * RFC1122: packets with a multicast source address are 493 * not allowed. 494 */ 495 if (IN_MULTICAST(ip->ip_src.s_addr)) { 496 ipstat.ips_badaddr++; 497 goto bad; 498 } 499 500 /* 127/8 must not appear on wire - RFC1122 */ 501 if ((ntohl(ip->ip_dst.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET || 502 (ntohl(ip->ip_src.s_addr) >> IN_CLASSA_NSHIFT) == IN_LOOPBACKNET) { 503 if ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) { 504 ipstat.ips_badaddr++; 505 goto bad; 506 } 507 } 508 509 switch (m->m_pkthdr.csum_flags & 510 ((m->m_pkthdr.rcvif->if_csum_flags_rx & M_CSUM_IPv4) | 511 M_CSUM_IPv4_BAD)) { 512 case M_CSUM_IPv4|M_CSUM_IPv4_BAD: 513 INET_CSUM_COUNTER_INCR(&ip_hwcsum_bad); 514 goto badcsum; 515 516 case M_CSUM_IPv4: 517 /* Checksum was okay. */ 518 INET_CSUM_COUNTER_INCR(&ip_hwcsum_ok); 519 break; 520 521 default: 522 /* Must compute it ourselves. */ 523 INET_CSUM_COUNTER_INCR(&ip_swcsum); 524 if (in_cksum(m, hlen) != 0) 525 goto bad; 526 break; 527 } 528 529 /* Retrieve the packet length. */ 530 len = ntohs(ip->ip_len); 531 532 /* 533 * Check for additional length bogosity 534 */ 535 if (len < hlen) { 536 ipstat.ips_badlen++; 537 goto bad; 538 } 539 540 /* 541 * Check that the amount of data in the buffers 542 * is as at least much as the IP header would have us expect. 543 * Trim mbufs if longer than we expect. 544 * Drop packet if shorter than we expect. 545 */ 546 if (m->m_pkthdr.len < len) { 547 ipstat.ips_tooshort++; 548 goto bad; 549 } 550 if (m->m_pkthdr.len > len) { 551 if (m->m_len == m->m_pkthdr.len) { 552 m->m_len = len; 553 m->m_pkthdr.len = len; 554 } else 555 m_adj(m, len - m->m_pkthdr.len); 556 } 557 558 #ifdef IPSEC 559 /* ipflow (IP fast forwarding) is not compatible with IPsec. */ 560 m->m_flags &= ~M_CANFASTFWD; 561 #else 562 /* 563 * Assume that we can create a fast-forward IP flow entry 564 * based on this packet. 565 */ 566 m->m_flags |= M_CANFASTFWD; 567 #endif 568 569 #ifdef PFIL_HOOKS 570 /* 571 * Run through list of hooks for input packets. If there are any 572 * filters which require that additional packets in the flow are 573 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 574 * Note that filters must _never_ set this flag, as another filter 575 * in the list may have previously cleared it. 576 */ 577 /* 578 * let ipfilter look at packet on the wire, 579 * not the decapsulated packet. 580 */ 581 #ifdef IPSEC 582 if (!ipsec_getnhist(m)) 583 #else 584 if (1) 585 #endif 586 { 587 struct in_addr odst; 588 589 odst = ip->ip_dst; 590 if (pfil_run_hooks(&inet_pfil_hook, &m, m->m_pkthdr.rcvif, 591 PFIL_IN) != 0) 592 return; 593 if (m == NULL) 594 return; 595 ip = mtod(m, struct ip *); 596 hlen = ip->ip_hl << 2; 597 srcrt = (odst.s_addr != ip->ip_dst.s_addr); 598 } 599 #endif /* PFIL_HOOKS */ 600 601 #ifdef ALTQ 602 /* XXX Temporary until ALTQ is changed to use a pfil hook */ 603 if (altq_input != NULL && (*altq_input)(m, AF_INET) == 0) { 604 /* packet dropped by traffic conditioner */ 605 return; 606 } 607 #endif 608 609 /* 610 * Process options and, if not destined for us, 611 * ship it on. ip_dooptions returns 1 when an 612 * error was detected (causing an icmp message 613 * to be sent and the original packet to be freed). 614 */ 615 ip_nhops = 0; /* for source routed packets */ 616 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 617 return; 618 619 /* 620 * Enable a consistency check between the destination address 621 * and the arrival interface for a unicast packet (the RFC 1122 622 * strong ES model) if IP forwarding is disabled and the packet 623 * is not locally generated. 624 * 625 * XXX - Checking also should be disabled if the destination 626 * address is ipnat'ed to a different interface. 627 * 628 * XXX - Checking is incompatible with IP aliases added 629 * to the loopback interface instead of the interface where 630 * the packets are received. 631 * 632 * XXX - We need to add a per ifaddr flag for this so that 633 * we get finer grain control. 634 */ 635 checkif = ip_checkinterface && (ipforwarding == 0) && 636 (m->m_pkthdr.rcvif != NULL) && 637 ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0); 638 639 /* 640 * Check our list of addresses, to see if the packet is for us. 641 * 642 * Traditional 4.4BSD did not consult IFF_UP at all. 643 * The behavior here is to treat addresses on !IFF_UP interface 644 * as not mine. 645 */ 646 downmatch = 0; 647 LIST_FOREACH(ia, &IN_IFADDR_HASH(ip->ip_dst.s_addr), ia_hash) { 648 if (in_hosteq(ia->ia_addr.sin_addr, ip->ip_dst)) { 649 if (checkif && ia->ia_ifp != m->m_pkthdr.rcvif) 650 continue; 651 if ((ia->ia_ifp->if_flags & IFF_UP) != 0) 652 break; 653 else 654 downmatch++; 655 } 656 } 657 if (ia != NULL) 658 goto ours; 659 if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 660 TAILQ_FOREACH(ifa, &m->m_pkthdr.rcvif->if_addrlist, ifa_list) { 661 if (ifa->ifa_addr->sa_family != AF_INET) 662 continue; 663 ia = ifatoia(ifa); 664 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 665 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 666 /* 667 * Look for all-0's host part (old broadcast addr), 668 * either for subnet or net. 669 */ 670 ip->ip_dst.s_addr == ia->ia_subnet || 671 ip->ip_dst.s_addr == ia->ia_net) 672 goto ours; 673 /* 674 * An interface with IP address zero accepts 675 * all packets that arrive on that interface. 676 */ 677 if (in_nullhost(ia->ia_addr.sin_addr)) 678 goto ours; 679 } 680 } 681 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 682 struct in_multi *inm; 683 #ifdef MROUTING 684 extern struct socket *ip_mrouter; 685 686 if (M_READONLY(m)) { 687 if ((m = m_pullup(m, hlen)) == 0) { 688 ipstat.ips_toosmall++; 689 return; 690 } 691 ip = mtod(m, struct ip *); 692 } 693 694 if (ip_mrouter) { 695 /* 696 * If we are acting as a multicast router, all 697 * incoming multicast packets are passed to the 698 * kernel-level multicast forwarding function. 699 * The packet is returned (relatively) intact; if 700 * ip_mforward() returns a non-zero value, the packet 701 * must be discarded, else it may be accepted below. 702 * 703 * (The IP ident field is put in the same byte order 704 * as expected when ip_mforward() is called from 705 * ip_output().) 706 */ 707 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 708 ipstat.ips_cantforward++; 709 m_freem(m); 710 return; 711 } 712 713 /* 714 * The process-level routing demon needs to receive 715 * all multicast IGMP packets, whether or not this 716 * host belongs to their destination groups. 717 */ 718 if (ip->ip_p == IPPROTO_IGMP) 719 goto ours; 720 ipstat.ips_forward++; 721 } 722 #endif 723 /* 724 * See if we belong to the destination multicast group on the 725 * arrival interface. 726 */ 727 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 728 if (inm == NULL) { 729 ipstat.ips_cantforward++; 730 m_freem(m); 731 return; 732 } 733 goto ours; 734 } 735 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 736 in_nullhost(ip->ip_dst)) 737 goto ours; 738 739 /* 740 * Not for us; forward if possible and desirable. 741 */ 742 if (ipforwarding == 0) { 743 ipstat.ips_cantforward++; 744 m_freem(m); 745 } else { 746 /* 747 * If ip_dst matched any of my address on !IFF_UP interface, 748 * and there's no IFF_UP interface that matches ip_dst, 749 * send icmp unreach. Forwarding it will result in in-kernel 750 * forwarding loop till TTL goes to 0. 751 */ 752 if (downmatch) { 753 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, 0, 0); 754 ipstat.ips_cantforward++; 755 return; 756 } 757 #ifdef IPSEC 758 if (ipsec4_in_reject(m, NULL)) { 759 ipsecstat.in_polvio++; 760 goto bad; 761 } 762 #endif 763 #ifdef FAST_IPSEC 764 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 765 s = splsoftnet(); 766 if (mtag != NULL) { 767 tdbi = (struct tdb_ident *)(mtag + 1); 768 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 769 } else { 770 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 771 IP_FORWARDING, &error); 772 } 773 if (sp == NULL) { /* NB: can happen if error */ 774 splx(s); 775 /*XXX error stat???*/ 776 DPRINTF(("ip_input: no SP for forwarding\n")); /*XXX*/ 777 goto bad; 778 } 779 780 /* 781 * Check security policy against packet attributes. 782 */ 783 error = ipsec_in_reject(sp, m); 784 KEY_FREESP(&sp); 785 splx(s); 786 if (error) { 787 ipstat.ips_cantforward++; 788 goto bad; 789 } 790 #endif /* FAST_IPSEC */ 791 792 ip_forward(m, srcrt); 793 } 794 return; 795 796 ours: 797 /* 798 * If offset or IP_MF are set, must reassemble. 799 * Otherwise, nothing need be done. 800 * (We could look in the reassembly queue to see 801 * if the packet was previously fragmented, 802 * but it's not worth the time; just let them time out.) 803 */ 804 if (ip->ip_off & ~htons(IP_DF|IP_RF)) { 805 if (M_READONLY(m)) { 806 if ((m = m_pullup(m, hlen)) == NULL) { 807 ipstat.ips_toosmall++; 808 goto bad; 809 } 810 ip = mtod(m, struct ip *); 811 } 812 813 /* 814 * Look for queue of fragments 815 * of this datagram. 816 */ 817 IPQ_LOCK(); 818 LIST_FOREACH(fp, &ipq, ipq_q) 819 if (ip->ip_id == fp->ipq_id && 820 in_hosteq(ip->ip_src, fp->ipq_src) && 821 in_hosteq(ip->ip_dst, fp->ipq_dst) && 822 ip->ip_p == fp->ipq_p) 823 goto found; 824 fp = 0; 825 found: 826 827 /* 828 * Adjust ip_len to not reflect header, 829 * set ipqe_mff if more fragments are expected, 830 * convert offset of this to bytes. 831 */ 832 ip->ip_len = htons(ntohs(ip->ip_len) - hlen); 833 mff = (ip->ip_off & htons(IP_MF)) != 0; 834 if (mff) { 835 /* 836 * Make sure that fragments have a data length 837 * that's a non-zero multiple of 8 bytes. 838 */ 839 if (ntohs(ip->ip_len) == 0 || 840 (ntohs(ip->ip_len) & 0x7) != 0) { 841 ipstat.ips_badfrags++; 842 IPQ_UNLOCK(); 843 goto bad; 844 } 845 } 846 ip->ip_off = htons((ntohs(ip->ip_off) & IP_OFFMASK) << 3); 847 848 /* 849 * If datagram marked as having more fragments 850 * or if this is not the first fragment, 851 * attempt reassembly; if it succeeds, proceed. 852 */ 853 if (mff || ip->ip_off != htons(0)) { 854 ipstat.ips_fragments++; 855 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 856 if (ipqe == NULL) { 857 ipstat.ips_rcvmemdrop++; 858 IPQ_UNLOCK(); 859 goto bad; 860 } 861 ipqe->ipqe_mff = mff; 862 ipqe->ipqe_m = m; 863 ipqe->ipqe_ip = ip; 864 m = ip_reass(ipqe, fp); 865 if (m == 0) { 866 IPQ_UNLOCK(); 867 return; 868 } 869 ipstat.ips_reassembled++; 870 ip = mtod(m, struct ip *); 871 hlen = ip->ip_hl << 2; 872 ip->ip_len = htons(ntohs(ip->ip_len) + hlen); 873 } else 874 if (fp) 875 ip_freef(fp); 876 IPQ_UNLOCK(); 877 } 878 879 #if defined(IPSEC) 880 /* 881 * enforce IPsec policy checking if we are seeing last header. 882 * note that we do not visit this with protocols with pcb layer 883 * code - like udp/tcp/raw ip. 884 */ 885 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0 && 886 ipsec4_in_reject(m, NULL)) { 887 ipsecstat.in_polvio++; 888 goto bad; 889 } 890 #endif 891 #if FAST_IPSEC 892 /* 893 * enforce IPsec policy checking if we are seeing last header. 894 * note that we do not visit this with protocols with pcb layer 895 * code - like udp/tcp/raw ip. 896 */ 897 if ((inetsw[ip_protox[ip->ip_p]].pr_flags & PR_LASTHDR) != 0) { 898 /* 899 * Check if the packet has already had IPsec processing 900 * done. If so, then just pass it along. This tag gets 901 * set during AH, ESP, etc. input handling, before the 902 * packet is returned to the ip input queue for delivery. 903 */ 904 mtag = m_tag_find(m, PACKET_TAG_IPSEC_IN_DONE, NULL); 905 s = splsoftnet(); 906 if (mtag != NULL) { 907 tdbi = (struct tdb_ident *)(mtag + 1); 908 sp = ipsec_getpolicy(tdbi, IPSEC_DIR_INBOUND); 909 } else { 910 sp = ipsec_getpolicybyaddr(m, IPSEC_DIR_INBOUND, 911 IP_FORWARDING, &error); 912 } 913 if (sp != NULL) { 914 /* 915 * Check security policy against packet attributes. 916 */ 917 error = ipsec_in_reject(sp, m); 918 KEY_FREESP(&sp); 919 } else { 920 /* XXX error stat??? */ 921 error = EINVAL; 922 DPRINTF(("ip_input: no SP, packet discarded\n"));/*XXX*/ 923 goto bad; 924 } 925 splx(s); 926 if (error) 927 goto bad; 928 } 929 #endif /* FAST_IPSEC */ 930 931 /* 932 * Switch out to protocol's input routine. 933 */ 934 #if IFA_STATS 935 if (ia && ip) 936 ia->ia_ifa.ifa_data.ifad_inbytes += ntohs(ip->ip_len); 937 #endif 938 ipstat.ips_delivered++; 939 { 940 int off = hlen, nh = ip->ip_p; 941 942 (*inetsw[ip_protox[nh]].pr_input)(m, off, nh); 943 return; 944 } 945 bad: 946 m_freem(m); 947 return; 948 949 badcsum: 950 ipstat.ips_badsum++; 951 m_freem(m); 952 } 953 954 /* 955 * Take incoming datagram fragment and try to 956 * reassemble it into whole datagram. If a chain for 957 * reassembly of this datagram already exists, then it 958 * is given as fp; otherwise have to make a chain. 959 */ 960 struct mbuf * 961 ip_reass(ipqe, fp) 962 struct ipqent *ipqe; 963 struct ipq *fp; 964 { 965 struct mbuf *m = ipqe->ipqe_m; 966 struct ipqent *nq, *p, *q; 967 struct ip *ip; 968 struct mbuf *t; 969 int hlen = ipqe->ipqe_ip->ip_hl << 2; 970 int i, next; 971 972 IPQ_LOCK_CHECK(); 973 974 /* 975 * Presence of header sizes in mbufs 976 * would confuse code below. 977 */ 978 m->m_data += hlen; 979 m->m_len -= hlen; 980 981 /* 982 * If first fragment to arrive, create a reassembly queue. 983 */ 984 if (fp == 0) { 985 /* 986 * Enforce upper bound on number of fragmented packets 987 * for which we attempt reassembly; 988 * If maxfrag is 0, never accept fragments. 989 * If maxfrag is -1, accept all fragments without limitation. 990 */ 991 if (ip_maxfragpackets < 0) 992 ; 993 else if (ip_nfragpackets >= ip_maxfragpackets) 994 goto dropfrag; 995 ip_nfragpackets++; 996 MALLOC(fp, struct ipq *, sizeof (struct ipq), 997 M_FTABLE, M_NOWAIT); 998 if (fp == NULL) 999 goto dropfrag; 1000 LIST_INSERT_HEAD(&ipq, fp, ipq_q); 1001 fp->ipq_ttl = IPFRAGTTL; 1002 fp->ipq_p = ipqe->ipqe_ip->ip_p; 1003 fp->ipq_id = ipqe->ipqe_ip->ip_id; 1004 TAILQ_INIT(&fp->ipq_fragq); 1005 fp->ipq_src = ipqe->ipqe_ip->ip_src; 1006 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 1007 p = NULL; 1008 goto insert; 1009 } 1010 1011 /* 1012 * Find a segment which begins after this one does. 1013 */ 1014 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1015 p = q, q = TAILQ_NEXT(q, ipqe_q)) 1016 if (ntohs(q->ipqe_ip->ip_off) > ntohs(ipqe->ipqe_ip->ip_off)) 1017 break; 1018 1019 /* 1020 * If there is a preceding segment, it may provide some of 1021 * our data already. If so, drop the data from the incoming 1022 * segment. If it provides all of our data, drop us. 1023 */ 1024 if (p != NULL) { 1025 i = ntohs(p->ipqe_ip->ip_off) + ntohs(p->ipqe_ip->ip_len) - 1026 ntohs(ipqe->ipqe_ip->ip_off); 1027 if (i > 0) { 1028 if (i >= ntohs(ipqe->ipqe_ip->ip_len)) 1029 goto dropfrag; 1030 m_adj(ipqe->ipqe_m, i); 1031 ipqe->ipqe_ip->ip_off = 1032 htons(ntohs(ipqe->ipqe_ip->ip_off) + i); 1033 ipqe->ipqe_ip->ip_len = 1034 htons(ntohs(ipqe->ipqe_ip->ip_len) - i); 1035 } 1036 } 1037 1038 /* 1039 * While we overlap succeeding segments trim them or, 1040 * if they are completely covered, dequeue them. 1041 */ 1042 for (; q != NULL && 1043 ntohs(ipqe->ipqe_ip->ip_off) + ntohs(ipqe->ipqe_ip->ip_len) > 1044 ntohs(q->ipqe_ip->ip_off); q = nq) { 1045 i = (ntohs(ipqe->ipqe_ip->ip_off) + 1046 ntohs(ipqe->ipqe_ip->ip_len)) - ntohs(q->ipqe_ip->ip_off); 1047 if (i < ntohs(q->ipqe_ip->ip_len)) { 1048 q->ipqe_ip->ip_len = 1049 htons(ntohs(q->ipqe_ip->ip_len) - i); 1050 q->ipqe_ip->ip_off = 1051 htons(ntohs(q->ipqe_ip->ip_off) + i); 1052 m_adj(q->ipqe_m, i); 1053 break; 1054 } 1055 nq = TAILQ_NEXT(q, ipqe_q); 1056 m_freem(q->ipqe_m); 1057 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1058 pool_put(&ipqent_pool, q); 1059 } 1060 1061 insert: 1062 /* 1063 * Stick new segment in its place; 1064 * check for complete reassembly. 1065 */ 1066 if (p == NULL) { 1067 TAILQ_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 1068 } else { 1069 TAILQ_INSERT_AFTER(&fp->ipq_fragq, p, ipqe, ipqe_q); 1070 } 1071 next = 0; 1072 for (p = NULL, q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; 1073 p = q, q = TAILQ_NEXT(q, ipqe_q)) { 1074 if (ntohs(q->ipqe_ip->ip_off) != next) 1075 return (0); 1076 next += ntohs(q->ipqe_ip->ip_len); 1077 } 1078 if (p->ipqe_mff) 1079 return (0); 1080 1081 /* 1082 * Reassembly is complete. Check for a bogus message size and 1083 * concatenate fragments. 1084 */ 1085 q = TAILQ_FIRST(&fp->ipq_fragq); 1086 ip = q->ipqe_ip; 1087 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 1088 ipstat.ips_toolong++; 1089 ip_freef(fp); 1090 return (0); 1091 } 1092 m = q->ipqe_m; 1093 t = m->m_next; 1094 m->m_next = 0; 1095 m_cat(m, t); 1096 nq = TAILQ_NEXT(q, ipqe_q); 1097 pool_put(&ipqent_pool, q); 1098 for (q = nq; q != NULL; q = nq) { 1099 t = q->ipqe_m; 1100 nq = TAILQ_NEXT(q, ipqe_q); 1101 pool_put(&ipqent_pool, q); 1102 m_cat(m, t); 1103 } 1104 1105 /* 1106 * Create header for new ip packet by 1107 * modifying header of first packet; 1108 * dequeue and discard fragment reassembly header. 1109 * Make header visible. 1110 */ 1111 ip->ip_len = htons(next); 1112 ip->ip_src = fp->ipq_src; 1113 ip->ip_dst = fp->ipq_dst; 1114 LIST_REMOVE(fp, ipq_q); 1115 FREE(fp, M_FTABLE); 1116 ip_nfragpackets--; 1117 m->m_len += (ip->ip_hl << 2); 1118 m->m_data -= (ip->ip_hl << 2); 1119 /* some debugging cruft by sklower, below, will go away soon */ 1120 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 1121 int plen = 0; 1122 for (t = m; t; t = t->m_next) 1123 plen += t->m_len; 1124 m->m_pkthdr.len = plen; 1125 } 1126 return (m); 1127 1128 dropfrag: 1129 ipstat.ips_fragdropped++; 1130 m_freem(m); 1131 pool_put(&ipqent_pool, ipqe); 1132 return (0); 1133 } 1134 1135 /* 1136 * Free a fragment reassembly header and all 1137 * associated datagrams. 1138 */ 1139 void 1140 ip_freef(fp) 1141 struct ipq *fp; 1142 { 1143 struct ipqent *q, *p; 1144 1145 IPQ_LOCK_CHECK(); 1146 1147 for (q = TAILQ_FIRST(&fp->ipq_fragq); q != NULL; q = p) { 1148 p = TAILQ_NEXT(q, ipqe_q); 1149 m_freem(q->ipqe_m); 1150 TAILQ_REMOVE(&fp->ipq_fragq, q, ipqe_q); 1151 pool_put(&ipqent_pool, q); 1152 } 1153 LIST_REMOVE(fp, ipq_q); 1154 FREE(fp, M_FTABLE); 1155 ip_nfragpackets--; 1156 } 1157 1158 /* 1159 * IP timer processing; 1160 * if a timer expires on a reassembly 1161 * queue, discard it. 1162 */ 1163 void 1164 ip_slowtimo() 1165 { 1166 struct ipq *fp, *nfp; 1167 int s = splsoftnet(); 1168 1169 IPQ_LOCK(); 1170 for (fp = LIST_FIRST(&ipq); fp != NULL; fp = nfp) { 1171 nfp = LIST_NEXT(fp, ipq_q); 1172 if (--fp->ipq_ttl == 0) { 1173 ipstat.ips_fragtimeout++; 1174 ip_freef(fp); 1175 } 1176 } 1177 /* 1178 * If we are over the maximum number of fragments 1179 * (due to the limit being lowered), drain off 1180 * enough to get down to the new limit. 1181 */ 1182 if (ip_maxfragpackets < 0) 1183 ; 1184 else { 1185 while (ip_nfragpackets > ip_maxfragpackets && LIST_FIRST(&ipq)) 1186 ip_freef(LIST_FIRST(&ipq)); 1187 } 1188 IPQ_UNLOCK(); 1189 #ifdef GATEWAY 1190 ipflow_slowtimo(); 1191 #endif 1192 splx(s); 1193 } 1194 1195 /* 1196 * Drain off all datagram fragments. 1197 */ 1198 void 1199 ip_drain() 1200 { 1201 1202 /* 1203 * We may be called from a device's interrupt context. If 1204 * the ipq is already busy, just bail out now. 1205 */ 1206 if (ipq_lock_try() == 0) 1207 return; 1208 1209 while (LIST_FIRST(&ipq) != NULL) { 1210 ipstat.ips_fragdropped++; 1211 ip_freef(LIST_FIRST(&ipq)); 1212 } 1213 1214 IPQ_UNLOCK(); 1215 } 1216 1217 /* 1218 * Do option processing on a datagram, 1219 * possibly discarding it if bad options are encountered, 1220 * or forwarding it if source-routed. 1221 * Returns 1 if packet has been forwarded/freed, 1222 * 0 if the packet should be processed further. 1223 */ 1224 int 1225 ip_dooptions(m) 1226 struct mbuf *m; 1227 { 1228 struct ip *ip = mtod(m, struct ip *); 1229 u_char *cp, *cp0; 1230 struct ip_timestamp *ipt; 1231 struct in_ifaddr *ia; 1232 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 1233 struct in_addr dst; 1234 n_time ntime; 1235 1236 dst = ip->ip_dst; 1237 cp = (u_char *)(ip + 1); 1238 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 1239 for (; cnt > 0; cnt -= optlen, cp += optlen) { 1240 opt = cp[IPOPT_OPTVAL]; 1241 if (opt == IPOPT_EOL) 1242 break; 1243 if (opt == IPOPT_NOP) 1244 optlen = 1; 1245 else { 1246 if (cnt < IPOPT_OLEN + sizeof(*cp)) { 1247 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1248 goto bad; 1249 } 1250 optlen = cp[IPOPT_OLEN]; 1251 if (optlen < IPOPT_OLEN + sizeof(*cp) || optlen > cnt) { 1252 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1253 goto bad; 1254 } 1255 } 1256 switch (opt) { 1257 1258 default: 1259 break; 1260 1261 /* 1262 * Source routing with record. 1263 * Find interface with current destination address. 1264 * If none on this machine then drop if strictly routed, 1265 * or do nothing if loosely routed. 1266 * Record interface address and bring up next address 1267 * component. If strictly routed make sure next 1268 * address is on directly accessible net. 1269 */ 1270 case IPOPT_LSRR: 1271 case IPOPT_SSRR: 1272 if (ip_allowsrcrt == 0) { 1273 type = ICMP_UNREACH; 1274 code = ICMP_UNREACH_NET_PROHIB; 1275 goto bad; 1276 } 1277 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1278 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1279 goto bad; 1280 } 1281 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1282 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1283 goto bad; 1284 } 1285 ipaddr.sin_addr = ip->ip_dst; 1286 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1287 if (ia == 0) { 1288 if (opt == IPOPT_SSRR) { 1289 type = ICMP_UNREACH; 1290 code = ICMP_UNREACH_SRCFAIL; 1291 goto bad; 1292 } 1293 /* 1294 * Loose routing, and not at next destination 1295 * yet; nothing to do except forward. 1296 */ 1297 break; 1298 } 1299 off--; /* 0 origin */ 1300 if ((off + sizeof(struct in_addr)) > optlen) { 1301 /* 1302 * End of source route. Should be for us. 1303 */ 1304 save_rte(cp, ip->ip_src); 1305 break; 1306 } 1307 /* 1308 * locate outgoing interface 1309 */ 1310 bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr, 1311 sizeof(ipaddr.sin_addr)); 1312 if (opt == IPOPT_SSRR) 1313 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 1314 else 1315 ia = ip_rtaddr(ipaddr.sin_addr); 1316 if (ia == 0) { 1317 type = ICMP_UNREACH; 1318 code = ICMP_UNREACH_SRCFAIL; 1319 goto bad; 1320 } 1321 ip->ip_dst = ipaddr.sin_addr; 1322 bcopy((caddr_t)&ia->ia_addr.sin_addr, 1323 (caddr_t)(cp + off), sizeof(struct in_addr)); 1324 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1325 /* 1326 * Let ip_intr's mcast routing check handle mcast pkts 1327 */ 1328 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 1329 break; 1330 1331 case IPOPT_RR: 1332 if (optlen < IPOPT_OFFSET + sizeof(*cp)) { 1333 code = &cp[IPOPT_OLEN] - (u_char *)ip; 1334 goto bad; 1335 } 1336 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 1337 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 1338 goto bad; 1339 } 1340 /* 1341 * If no space remains, ignore. 1342 */ 1343 off--; /* 0 origin */ 1344 if ((off + sizeof(struct in_addr)) > optlen) 1345 break; 1346 bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr, 1347 sizeof(ipaddr.sin_addr)); 1348 /* 1349 * locate outgoing interface; if we're the destination, 1350 * use the incoming interface (should be same). 1351 */ 1352 if ((ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr)))) 1353 == NULL && 1354 (ia = ip_rtaddr(ipaddr.sin_addr)) == NULL) { 1355 type = ICMP_UNREACH; 1356 code = ICMP_UNREACH_HOST; 1357 goto bad; 1358 } 1359 bcopy((caddr_t)&ia->ia_addr.sin_addr, 1360 (caddr_t)(cp + off), sizeof(struct in_addr)); 1361 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 1362 break; 1363 1364 case IPOPT_TS: 1365 code = cp - (u_char *)ip; 1366 ipt = (struct ip_timestamp *)cp; 1367 if (ipt->ipt_len < 4 || ipt->ipt_len > 40) { 1368 code = (u_char *)&ipt->ipt_len - (u_char *)ip; 1369 goto bad; 1370 } 1371 if (ipt->ipt_ptr < 5) { 1372 code = (u_char *)&ipt->ipt_ptr - (u_char *)ip; 1373 goto bad; 1374 } 1375 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 1376 if (++ipt->ipt_oflw == 0) { 1377 code = (u_char *)&ipt->ipt_ptr - 1378 (u_char *)ip; 1379 goto bad; 1380 } 1381 break; 1382 } 1383 cp0 = (cp + ipt->ipt_ptr - 1); 1384 switch (ipt->ipt_flg) { 1385 1386 case IPOPT_TS_TSONLY: 1387 break; 1388 1389 case IPOPT_TS_TSANDADDR: 1390 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1391 sizeof(struct in_addr) > ipt->ipt_len) { 1392 code = (u_char *)&ipt->ipt_ptr - 1393 (u_char *)ip; 1394 goto bad; 1395 } 1396 ipaddr.sin_addr = dst; 1397 ia = ifatoia(ifaof_ifpforaddr(sintosa(&ipaddr), 1398 m->m_pkthdr.rcvif)); 1399 if (ia == 0) 1400 continue; 1401 bcopy(&ia->ia_addr.sin_addr, 1402 cp0, sizeof(struct in_addr)); 1403 ipt->ipt_ptr += sizeof(struct in_addr); 1404 break; 1405 1406 case IPOPT_TS_PRESPEC: 1407 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1408 sizeof(struct in_addr) > ipt->ipt_len) { 1409 code = (u_char *)&ipt->ipt_ptr - 1410 (u_char *)ip; 1411 goto bad; 1412 } 1413 bcopy(cp0, &ipaddr.sin_addr, 1414 sizeof(struct in_addr)); 1415 if (ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))) 1416 == NULL) 1417 continue; 1418 ipt->ipt_ptr += sizeof(struct in_addr); 1419 break; 1420 1421 default: 1422 /* XXX can't take &ipt->ipt_flg */ 1423 code = (u_char *)&ipt->ipt_ptr - 1424 (u_char *)ip + 1; 1425 goto bad; 1426 } 1427 ntime = iptime(); 1428 cp0 = (u_char *) &ntime; /* XXX grumble, GCC... */ 1429 bcopy(cp0, (caddr_t)cp + ipt->ipt_ptr - 1, 1430 sizeof(n_time)); 1431 ipt->ipt_ptr += sizeof(n_time); 1432 } 1433 } 1434 if (forward) { 1435 if (ip_forwsrcrt == 0) { 1436 type = ICMP_UNREACH; 1437 code = ICMP_UNREACH_SRCFAIL; 1438 goto bad; 1439 } 1440 ip_forward(m, 1); 1441 return (1); 1442 } 1443 return (0); 1444 bad: 1445 icmp_error(m, type, code, 0, 0); 1446 ipstat.ips_badoptions++; 1447 return (1); 1448 } 1449 1450 /* 1451 * Given address of next destination (final or next hop), 1452 * return internet address info of interface to be used to get there. 1453 */ 1454 struct in_ifaddr * 1455 ip_rtaddr(dst) 1456 struct in_addr dst; 1457 { 1458 struct sockaddr_in *sin; 1459 1460 sin = satosin(&ipforward_rt.ro_dst); 1461 1462 if (ipforward_rt.ro_rt == 0 || !in_hosteq(dst, sin->sin_addr)) { 1463 if (ipforward_rt.ro_rt) { 1464 RTFREE(ipforward_rt.ro_rt); 1465 ipforward_rt.ro_rt = 0; 1466 } 1467 sin->sin_family = AF_INET; 1468 sin->sin_len = sizeof(*sin); 1469 sin->sin_addr = dst; 1470 1471 rtalloc(&ipforward_rt); 1472 } 1473 if (ipforward_rt.ro_rt == 0) 1474 return ((struct in_ifaddr *)0); 1475 return (ifatoia(ipforward_rt.ro_rt->rt_ifa)); 1476 } 1477 1478 /* 1479 * Save incoming source route for use in replies, 1480 * to be picked up later by ip_srcroute if the receiver is interested. 1481 */ 1482 void 1483 save_rte(option, dst) 1484 u_char *option; 1485 struct in_addr dst; 1486 { 1487 unsigned olen; 1488 1489 olen = option[IPOPT_OLEN]; 1490 #ifdef DIAGNOSTIC 1491 if (ipprintfs) 1492 printf("save_rte: olen %d\n", olen); 1493 #endif /* 0 */ 1494 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1495 return; 1496 bcopy((caddr_t)option, (caddr_t)ip_srcrt.srcopt, olen); 1497 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1498 ip_srcrt.dst = dst; 1499 } 1500 1501 /* 1502 * Retrieve incoming source route for use in replies, 1503 * in the same form used by setsockopt. 1504 * The first hop is placed before the options, will be removed later. 1505 */ 1506 struct mbuf * 1507 ip_srcroute() 1508 { 1509 struct in_addr *p, *q; 1510 struct mbuf *m; 1511 1512 if (ip_nhops == 0) 1513 return ((struct mbuf *)0); 1514 m = m_get(M_DONTWAIT, MT_SOOPTS); 1515 if (m == 0) 1516 return ((struct mbuf *)0); 1517 1518 MCLAIM(m, &inetdomain.dom_mowner); 1519 #define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1520 1521 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1522 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1523 OPTSIZ; 1524 #ifdef DIAGNOSTIC 1525 if (ipprintfs) 1526 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1527 #endif 1528 1529 /* 1530 * First save first hop for return route 1531 */ 1532 p = &ip_srcrt.route[ip_nhops - 1]; 1533 *(mtod(m, struct in_addr *)) = *p--; 1534 #ifdef DIAGNOSTIC 1535 if (ipprintfs) 1536 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1537 #endif 1538 1539 /* 1540 * Copy option fields and padding (nop) to mbuf. 1541 */ 1542 ip_srcrt.nop = IPOPT_NOP; 1543 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1544 bcopy((caddr_t)&ip_srcrt.nop, 1545 mtod(m, caddr_t) + sizeof(struct in_addr), OPTSIZ); 1546 q = (struct in_addr *)(mtod(m, caddr_t) + 1547 sizeof(struct in_addr) + OPTSIZ); 1548 #undef OPTSIZ 1549 /* 1550 * Record return path as an IP source route, 1551 * reversing the path (pointers are now aligned). 1552 */ 1553 while (p >= ip_srcrt.route) { 1554 #ifdef DIAGNOSTIC 1555 if (ipprintfs) 1556 printf(" %x", ntohl(q->s_addr)); 1557 #endif 1558 *q++ = *p--; 1559 } 1560 /* 1561 * Last hop goes to final destination. 1562 */ 1563 *q = ip_srcrt.dst; 1564 #ifdef DIAGNOSTIC 1565 if (ipprintfs) 1566 printf(" %x\n", ntohl(q->s_addr)); 1567 #endif 1568 return (m); 1569 } 1570 1571 /* 1572 * Strip out IP options, at higher 1573 * level protocol in the kernel. 1574 * Second argument is buffer to which options 1575 * will be moved, and return value is their length. 1576 * XXX should be deleted; last arg currently ignored. 1577 */ 1578 void 1579 ip_stripoptions(m, mopt) 1580 struct mbuf *m; 1581 struct mbuf *mopt; 1582 { 1583 int i; 1584 struct ip *ip = mtod(m, struct ip *); 1585 caddr_t opts; 1586 int olen; 1587 1588 olen = (ip->ip_hl << 2) - sizeof (struct ip); 1589 opts = (caddr_t)(ip + 1); 1590 i = m->m_len - (sizeof (struct ip) + olen); 1591 bcopy(opts + olen, opts, (unsigned)i); 1592 m->m_len -= olen; 1593 if (m->m_flags & M_PKTHDR) 1594 m->m_pkthdr.len -= olen; 1595 ip->ip_len = htons(ntohs(ip->ip_len) - olen); 1596 ip->ip_hl = sizeof (struct ip) >> 2; 1597 } 1598 1599 const int inetctlerrmap[PRC_NCMDS] = { 1600 0, 0, 0, 0, 1601 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1602 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1603 EMSGSIZE, EHOSTUNREACH, 0, 0, 1604 0, 0, 0, 0, 1605 ENOPROTOOPT 1606 }; 1607 1608 /* 1609 * Forward a packet. If some error occurs return the sender 1610 * an icmp packet. Note we can't always generate a meaningful 1611 * icmp message because icmp doesn't have a large enough repertoire 1612 * of codes and types. 1613 * 1614 * If not forwarding, just drop the packet. This could be confusing 1615 * if ipforwarding was zero but some routing protocol was advancing 1616 * us as a gateway to somewhere. However, we must let the routing 1617 * protocol deal with that. 1618 * 1619 * The srcrt parameter indicates whether the packet is being forwarded 1620 * via a source route. 1621 */ 1622 void 1623 ip_forward(m, srcrt) 1624 struct mbuf *m; 1625 int srcrt; 1626 { 1627 struct ip *ip = mtod(m, struct ip *); 1628 struct sockaddr_in *sin; 1629 struct rtentry *rt; 1630 int error, type = 0, code = 0; 1631 struct mbuf *mcopy; 1632 n_long dest; 1633 struct ifnet *destifp; 1634 #if defined(IPSEC) || defined(FAST_IPSEC) 1635 struct ifnet dummyifp; 1636 #endif 1637 1638 /* 1639 * We are now in the output path. 1640 */ 1641 MCLAIM(m, &ip_tx_mowner); 1642 1643 /* 1644 * Clear any in-bound checksum flags for this packet. 1645 */ 1646 m->m_pkthdr.csum_flags = 0; 1647 1648 dest = 0; 1649 #ifdef DIAGNOSTIC 1650 if (ipprintfs) 1651 printf("forward: src %2.2x dst %2.2x ttl %x\n", 1652 ntohl(ip->ip_src.s_addr), 1653 ntohl(ip->ip_dst.s_addr), ip->ip_ttl); 1654 #endif 1655 if (m->m_flags & (M_BCAST|M_MCAST) || in_canforward(ip->ip_dst) == 0) { 1656 ipstat.ips_cantforward++; 1657 m_freem(m); 1658 return; 1659 } 1660 if (ip->ip_ttl <= IPTTLDEC) { 1661 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1662 return; 1663 } 1664 ip->ip_ttl -= IPTTLDEC; 1665 1666 sin = satosin(&ipforward_rt.ro_dst); 1667 if ((rt = ipforward_rt.ro_rt) == 0 || 1668 !in_hosteq(ip->ip_dst, sin->sin_addr)) { 1669 if (ipforward_rt.ro_rt) { 1670 RTFREE(ipforward_rt.ro_rt); 1671 ipforward_rt.ro_rt = 0; 1672 } 1673 sin->sin_family = AF_INET; 1674 sin->sin_len = sizeof(struct sockaddr_in); 1675 sin->sin_addr = ip->ip_dst; 1676 1677 rtalloc(&ipforward_rt); 1678 if (ipforward_rt.ro_rt == 0) { 1679 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0); 1680 return; 1681 } 1682 rt = ipforward_rt.ro_rt; 1683 } 1684 1685 /* 1686 * Save at most 68 bytes of the packet in case 1687 * we need to generate an ICMP message to the src. 1688 * Pullup to avoid sharing mbuf cluster between m and mcopy. 1689 */ 1690 mcopy = m_copym(m, 0, imin(ntohs(ip->ip_len), 68), M_DONTWAIT); 1691 if (mcopy) 1692 mcopy = m_pullup(mcopy, ip->ip_hl << 2); 1693 1694 /* 1695 * If forwarding packet using same interface that it came in on, 1696 * perhaps should send a redirect to sender to shortcut a hop. 1697 * Only send redirect if source is sending directly to us, 1698 * and if packet was not source routed (or has any options). 1699 * Also, don't send redirect if forwarding using a default route 1700 * or a route modified by a redirect. 1701 */ 1702 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1703 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1704 !in_nullhost(satosin(rt_key(rt))->sin_addr) && 1705 ipsendredirects && !srcrt) { 1706 if (rt->rt_ifa && 1707 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1708 ifatoia(rt->rt_ifa)->ia_subnet) { 1709 if (rt->rt_flags & RTF_GATEWAY) 1710 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1711 else 1712 dest = ip->ip_dst.s_addr; 1713 /* 1714 * Router requirements says to only send host 1715 * redirects. 1716 */ 1717 type = ICMP_REDIRECT; 1718 code = ICMP_REDIRECT_HOST; 1719 #ifdef DIAGNOSTIC 1720 if (ipprintfs) 1721 printf("redirect (%d) to %x\n", code, 1722 (u_int32_t)dest); 1723 #endif 1724 } 1725 } 1726 1727 error = ip_output(m, (struct mbuf *)0, &ipforward_rt, 1728 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 1729 (struct ip_moptions *)NULL, (struct socket *)NULL); 1730 1731 if (error) 1732 ipstat.ips_cantforward++; 1733 else { 1734 ipstat.ips_forward++; 1735 if (type) 1736 ipstat.ips_redirectsent++; 1737 else { 1738 if (mcopy) { 1739 #ifdef GATEWAY 1740 if (mcopy->m_flags & M_CANFASTFWD) 1741 ipflow_create(&ipforward_rt, mcopy); 1742 #endif 1743 m_freem(mcopy); 1744 } 1745 return; 1746 } 1747 } 1748 if (mcopy == NULL) 1749 return; 1750 destifp = NULL; 1751 1752 switch (error) { 1753 1754 case 0: /* forwarded, but need redirect */ 1755 /* type, code set above */ 1756 break; 1757 1758 case ENETUNREACH: /* shouldn't happen, checked above */ 1759 case EHOSTUNREACH: 1760 case ENETDOWN: 1761 case EHOSTDOWN: 1762 default: 1763 type = ICMP_UNREACH; 1764 code = ICMP_UNREACH_HOST; 1765 break; 1766 1767 case EMSGSIZE: 1768 type = ICMP_UNREACH; 1769 code = ICMP_UNREACH_NEEDFRAG; 1770 #if !defined(IPSEC) && !defined(FAST_IPSEC) 1771 if (ipforward_rt.ro_rt) 1772 destifp = ipforward_rt.ro_rt->rt_ifp; 1773 #else 1774 /* 1775 * If the packet is routed over IPsec tunnel, tell the 1776 * originator the tunnel MTU. 1777 * tunnel MTU = if MTU - sizeof(IP) - ESP/AH hdrsiz 1778 * XXX quickhack!!! 1779 */ 1780 if (ipforward_rt.ro_rt) { 1781 struct secpolicy *sp; 1782 int ipsecerror; 1783 size_t ipsechdr; 1784 struct route *ro; 1785 1786 sp = ipsec4_getpolicybyaddr(mcopy, 1787 IPSEC_DIR_OUTBOUND, IP_FORWARDING, 1788 &ipsecerror); 1789 1790 if (sp == NULL) 1791 destifp = ipforward_rt.ro_rt->rt_ifp; 1792 else { 1793 /* count IPsec header size */ 1794 ipsechdr = ipsec4_hdrsiz(mcopy, 1795 IPSEC_DIR_OUTBOUND, NULL); 1796 1797 /* 1798 * find the correct route for outer IPv4 1799 * header, compute tunnel MTU. 1800 * 1801 * XXX BUG ALERT 1802 * The "dummyifp" code relies upon the fact 1803 * that icmp_error() touches only ifp->if_mtu. 1804 */ 1805 /*XXX*/ 1806 destifp = NULL; 1807 if (sp->req != NULL 1808 && sp->req->sav != NULL 1809 && sp->req->sav->sah != NULL) { 1810 ro = &sp->req->sav->sah->sa_route; 1811 if (ro->ro_rt && ro->ro_rt->rt_ifp) { 1812 dummyifp.if_mtu = 1813 ro->ro_rt->rt_rmx.rmx_mtu ? 1814 ro->ro_rt->rt_rmx.rmx_mtu : 1815 ro->ro_rt->rt_ifp->if_mtu; 1816 dummyifp.if_mtu -= ipsechdr; 1817 destifp = &dummyifp; 1818 } 1819 } 1820 1821 #ifdef IPSEC 1822 key_freesp(sp); 1823 #else 1824 KEY_FREESP(&sp); 1825 #endif 1826 } 1827 } 1828 #endif /*IPSEC*/ 1829 ipstat.ips_cantfrag++; 1830 break; 1831 1832 case ENOBUFS: 1833 #if 1 1834 /* 1835 * a router should not generate ICMP_SOURCEQUENCH as 1836 * required in RFC1812 Requirements for IP Version 4 Routers. 1837 * source quench could be a big problem under DoS attacks, 1838 * or if the underlying interface is rate-limited. 1839 */ 1840 if (mcopy) 1841 m_freem(mcopy); 1842 return; 1843 #else 1844 type = ICMP_SOURCEQUENCH; 1845 code = 0; 1846 break; 1847 #endif 1848 } 1849 icmp_error(mcopy, type, code, dest, destifp); 1850 } 1851 1852 void 1853 ip_savecontrol(inp, mp, ip, m) 1854 struct inpcb *inp; 1855 struct mbuf **mp; 1856 struct ip *ip; 1857 struct mbuf *m; 1858 { 1859 1860 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 1861 struct timeval tv; 1862 1863 microtime(&tv); 1864 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1865 SCM_TIMESTAMP, SOL_SOCKET); 1866 if (*mp) 1867 mp = &(*mp)->m_next; 1868 } 1869 if (inp->inp_flags & INP_RECVDSTADDR) { 1870 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst, 1871 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 1872 if (*mp) 1873 mp = &(*mp)->m_next; 1874 } 1875 #ifdef notyet 1876 /* 1877 * XXX 1878 * Moving these out of udp_input() made them even more broken 1879 * than they already were. 1880 * - fenner (at) parc.xerox.com 1881 */ 1882 /* options were tossed already */ 1883 if (inp->inp_flags & INP_RECVOPTS) { 1884 *mp = sbcreatecontrol((caddr_t) opts_deleted_above, 1885 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 1886 if (*mp) 1887 mp = &(*mp)->m_next; 1888 } 1889 /* ip_srcroute doesn't do what we want here, need to fix */ 1890 if (inp->inp_flags & INP_RECVRETOPTS) { 1891 *mp = sbcreatecontrol((caddr_t) ip_srcroute(), 1892 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 1893 if (*mp) 1894 mp = &(*mp)->m_next; 1895 } 1896 #endif 1897 if (inp->inp_flags & INP_RECVIF) { 1898 struct sockaddr_dl sdl; 1899 1900 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]); 1901 sdl.sdl_family = AF_LINK; 1902 sdl.sdl_index = m->m_pkthdr.rcvif ? 1903 m->m_pkthdr.rcvif->if_index : 0; 1904 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0; 1905 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len, 1906 IP_RECVIF, IPPROTO_IP); 1907 if (*mp) 1908 mp = &(*mp)->m_next; 1909 } 1910 } 1911 1912 int 1913 ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 1914 int *name; 1915 u_int namelen; 1916 void *oldp; 1917 size_t *oldlenp; 1918 void *newp; 1919 size_t newlen; 1920 { 1921 extern int subnetsarelocal, hostzeroisbroadcast; 1922 1923 int error, old; 1924 1925 /* All sysctl names (except ifq.*) at this level are terminal. */ 1926 if ((namelen != 1) && !(namelen == 2 && name[0] == IPCTL_IFQ)) 1927 return (ENOTDIR); 1928 1929 switch (name[0]) { 1930 case IPCTL_FORWARDING: 1931 return (sysctl_int(oldp, oldlenp, newp, newlen, &ipforwarding)); 1932 case IPCTL_SENDREDIRECTS: 1933 return (sysctl_int(oldp, oldlenp, newp, newlen, 1934 &ipsendredirects)); 1935 case IPCTL_DEFTTL: 1936 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_defttl)); 1937 #ifdef notyet 1938 case IPCTL_DEFMTU: 1939 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu)); 1940 #endif 1941 case IPCTL_FORWSRCRT: 1942 /* Don't allow this to change in a secure environment. */ 1943 if (securelevel > 0) 1944 return (sysctl_rdint(oldp, oldlenp, newp, 1945 ip_forwsrcrt)); 1946 else 1947 return (sysctl_int(oldp, oldlenp, newp, newlen, 1948 &ip_forwsrcrt)); 1949 case IPCTL_DIRECTEDBCAST: 1950 return (sysctl_int(oldp, oldlenp, newp, newlen, 1951 &ip_directedbcast)); 1952 case IPCTL_ALLOWSRCRT: 1953 return (sysctl_int(oldp, oldlenp, newp, newlen, 1954 &ip_allowsrcrt)); 1955 case IPCTL_SUBNETSARELOCAL: 1956 return (sysctl_int(oldp, oldlenp, newp, newlen, 1957 &subnetsarelocal)); 1958 case IPCTL_MTUDISC: 1959 error = sysctl_int(oldp, oldlenp, newp, newlen, 1960 &ip_mtudisc); 1961 if (error == 0 && ip_mtudisc == 0) 1962 rt_timer_queue_remove_all(ip_mtudisc_timeout_q, TRUE); 1963 return error; 1964 case IPCTL_ANONPORTMIN: 1965 old = anonportmin; 1966 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmin); 1967 if (anonportmin >= anonportmax || anonportmin < 0 1968 || anonportmin > 65535 1969 #ifndef IPNOPRIVPORTS 1970 || anonportmin < IPPORT_RESERVED 1971 #endif 1972 ) { 1973 anonportmin = old; 1974 return (EINVAL); 1975 } 1976 return (error); 1977 case IPCTL_ANONPORTMAX: 1978 old = anonportmax; 1979 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmax); 1980 if (anonportmin >= anonportmax || anonportmax < 0 1981 || anonportmax > 65535 1982 #ifndef IPNOPRIVPORTS 1983 || anonportmax < IPPORT_RESERVED 1984 #endif 1985 ) { 1986 anonportmax = old; 1987 return (EINVAL); 1988 } 1989 return (error); 1990 case IPCTL_MTUDISCTIMEOUT: 1991 old = ip_mtudisc_timeout; 1992 error = sysctl_int(oldp, oldlenp, newp, newlen, 1993 &ip_mtudisc_timeout); 1994 if (ip_mtudisc_timeout < 0) { 1995 ip_mtudisc_timeout = old; 1996 return (EINVAL); 1997 } 1998 if (error == 0) 1999 rt_timer_queue_change(ip_mtudisc_timeout_q, 2000 ip_mtudisc_timeout); 2001 return (error); 2002 #ifdef GATEWAY 2003 case IPCTL_MAXFLOWS: 2004 { 2005 int s; 2006 2007 error = sysctl_int(oldp, oldlenp, newp, newlen, 2008 &ip_maxflows); 2009 s = splsoftnet(); 2010 ipflow_reap(0); 2011 splx(s); 2012 return (error); 2013 } 2014 #endif 2015 case IPCTL_HOSTZEROBROADCAST: 2016 return (sysctl_int(oldp, oldlenp, newp, newlen, 2017 &hostzeroisbroadcast)); 2018 #if NGIF > 0 2019 case IPCTL_GIF_TTL: 2020 return (sysctl_int(oldp, oldlenp, newp, newlen, 2021 &ip_gif_ttl)); 2022 #endif 2023 2024 #if NGRE > 0 2025 case IPCTL_GRE_TTL: 2026 return (sysctl_int(oldp, oldlenp, newp, newlen, 2027 &ip_gre_ttl)); 2028 #endif 2029 2030 #ifndef IPNOPRIVPORTS 2031 case IPCTL_LOWPORTMIN: 2032 old = lowportmin; 2033 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmin); 2034 if (lowportmin >= lowportmax 2035 || lowportmin > IPPORT_RESERVEDMAX 2036 || lowportmin < IPPORT_RESERVEDMIN 2037 ) { 2038 lowportmin = old; 2039 return (EINVAL); 2040 } 2041 return (error); 2042 case IPCTL_LOWPORTMAX: 2043 old = lowportmax; 2044 error = sysctl_int(oldp, oldlenp, newp, newlen, &lowportmax); 2045 if (lowportmin >= lowportmax 2046 || lowportmax > IPPORT_RESERVEDMAX 2047 || lowportmax < IPPORT_RESERVEDMIN 2048 ) { 2049 lowportmax = old; 2050 return (EINVAL); 2051 } 2052 return (error); 2053 #endif 2054 2055 case IPCTL_MAXFRAGPACKETS: 2056 return (sysctl_int(oldp, oldlenp, newp, newlen, 2057 &ip_maxfragpackets)); 2058 2059 case IPCTL_CHECKINTERFACE: 2060 return (sysctl_int(oldp, oldlenp, newp, newlen, 2061 &ip_checkinterface)); 2062 case IPCTL_IFQ: 2063 return (sysctl_ifq(name+1, namelen-1, 2064 oldp, oldlenp, newp, newlen, 2065 &ipintrq)); 2066 2067 default: 2068 return (EOPNOTSUPP); 2069 } 2070 /* NOTREACHED */ 2071 } 2072
Indexes created Wed Sep 24 05:09:52 GMT 2025