ip_input.c revision 1.88
1/* $NetBSD: ip_input.c,v 1.88 1999/06/26 06:16:48 sommerfeld Exp $ */ 2 3/*- 4 * Copyright (c) 1998 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Public Access Networks Corporation ("Panix"). It was developed under 9 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the NetBSD 22 * Foundation, Inc. and its contributors. 23 * 4. Neither the name of The NetBSD Foundation nor the names of its 24 * contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 37 * POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40/* 41 * Copyright (c) 1982, 1986, 1988, 1993 42 * The Regents of the University of California. All rights reserved. 43 * 44 * Redistribution and use in source and binary forms, with or without 45 * modification, are permitted provided that the following conditions 46 * are met: 47 * 1. Redistributions of source code must retain the above copyright 48 * notice, this list of conditions and the following disclaimer. 49 * 2. Redistributions in binary form must reproduce the above copyright 50 * notice, this list of conditions and the following disclaimer in the 51 * documentation and/or other materials provided with the distribution. 52 * 3. All advertising materials mentioning features or use of this software 53 * must display the following acknowledgement: 54 * This product includes software developed by the University of 55 * California, Berkeley and its contributors. 56 * 4. Neither the name of the University nor the names of its contributors 57 * may be used to endorse or promote products derived from this software 58 * without specific prior written permission. 59 * 60 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 61 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 62 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 63 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 64 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 65 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 66 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 67 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 68 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 69 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 70 * SUCH DAMAGE. 71 * 72 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 73 */ 74 75#include "opt_gateway.h" 76#include "opt_pfil_hooks.h" 77#include "opt_mrouting.h" 78 79#include <sys/param.h> 80#include <sys/systm.h> 81#include <sys/malloc.h> 82#include <sys/mbuf.h> 83#include <sys/domain.h> 84#include <sys/protosw.h> 85#include <sys/socket.h> 86#include <sys/socketvar.h> 87#include <sys/errno.h> 88#include <sys/time.h> 89#include <sys/kernel.h> 90#include <sys/proc.h> 91#include <sys/pool.h> 92 93#include <vm/vm.h> 94#include <sys/sysctl.h> 95 96#include <net/if.h> 97#include <net/if_dl.h> 98#include <net/route.h> 99#include <net/pfil.h> 100 101#include <netinet/in.h> 102#include <netinet/in_systm.h> 103#include <netinet/ip.h> 104#include <netinet/in_pcb.h> 105#include <netinet/in_var.h> 106#include <netinet/ip_var.h> 107#include <netinet/ip_icmp.h> 108 109#ifndef IPFORWARDING 110#ifdef GATEWAY 111#define IPFORWARDING 1 /* forward IP packets not for us */ 112#else /* GATEWAY */ 113#define IPFORWARDING 0 /* don't forward IP packets not for us */ 114#endif /* GATEWAY */ 115#endif /* IPFORWARDING */ 116#ifndef IPSENDREDIRECTS 117#define IPSENDREDIRECTS 1 118#endif 119#ifndef IPFORWSRCRT 120#define IPFORWSRCRT 1 /* forward source-routed packets */ 121#endif 122#ifndef IPALLOWSRCRT 123#define IPALLOWSRCRT 1 /* allow source-routed packets */ 124#endif 125#ifndef IPMTUDISC 126#define IPMTUDISC 0 127#endif 128#ifndef IPMTUDISCTIMEOUT 129#define IPMTUDISCTIMEOUT (10 * 60) /* as per RFC 1191 */ 130#endif 131 132/* 133 * Note: DIRECTED_BROADCAST is handled this way so that previous 134 * configuration using this option will Just Work. 135 */ 136#ifndef IPDIRECTEDBCAST 137#ifdef DIRECTED_BROADCAST 138#define IPDIRECTEDBCAST 1 139#else 140#define IPDIRECTEDBCAST 0 141#endif /* DIRECTED_BROADCAST */ 142#endif /* IPDIRECTEDBCAST */ 143int ipforwarding = IPFORWARDING; 144int ipsendredirects = IPSENDREDIRECTS; 145int ip_defttl = IPDEFTTL; 146int ip_forwsrcrt = IPFORWSRCRT; 147int ip_directedbcast = IPDIRECTEDBCAST; 148int ip_allowsrcrt = IPALLOWSRCRT; 149int ip_mtudisc = IPMTUDISC; 150u_int ip_mtudisc_timeout = IPMTUDISCTIMEOUT; 151#ifdef DIAGNOSTIC 152int ipprintfs = 0; 153#endif 154 155struct rttimer_queue *ip_mtudisc_timeout_q = NULL; 156 157extern struct domain inetdomain; 158extern struct protosw inetsw[]; 159u_char ip_protox[IPPROTO_MAX]; 160int ipqmaxlen = IFQ_MAXLEN; 161struct in_ifaddrhead in_ifaddr; 162struct in_ifaddrhashhead *in_ifaddrhashtbl; 163struct ifqueue ipintrq; 164struct ipstat ipstat; 165u_int16_t ip_id; 166int ip_defttl; 167 168struct ipqhead ipq; 169int ipq_locked; 170 171static __inline int ipq_lock_try __P((void)); 172static __inline void ipq_unlock __P((void)); 173 174static __inline int 175ipq_lock_try() 176{ 177 int s; 178 179 s = splimp(); 180 if (ipq_locked) { 181 splx(s); 182 return (0); 183 } 184 ipq_locked = 1; 185 splx(s); 186 return (1); 187} 188 189static __inline void 190ipq_unlock() 191{ 192 int s; 193 194 s = splimp(); 195 ipq_locked = 0; 196 splx(s); 197} 198 199#ifdef DIAGNOSTIC 200#define IPQ_LOCK() \ 201do { \ 202 if (ipq_lock_try() == 0) { \ 203 printf("%s:%d: ipq already locked\n", __FILE__, __LINE__); \ 204 panic("ipq_lock"); \ 205 } \ 206} while (0) 207#define IPQ_LOCK_CHECK() \ 208do { \ 209 if (ipq_locked == 0) { \ 210 printf("%s:%d: ipq lock not held\n", __FILE__, __LINE__); \ 211 panic("ipq lock check"); \ 212 } \ 213} while (0) 214#else 215#define IPQ_LOCK() (void) ipq_lock_try() 216#define IPQ_LOCK_CHECK() /* nothing */ 217#endif 218 219#define IPQ_UNLOCK() ipq_unlock() 220 221struct pool ipqent_pool; 222 223/* 224 * We need to save the IP options in case a protocol wants to respond 225 * to an incoming packet over the same route if the packet got here 226 * using IP source routing. This allows connection establishment and 227 * maintenance when the remote end is on a network that is not known 228 * to us. 229 */ 230int ip_nhops = 0; 231static struct ip_srcrt { 232 struct in_addr dst; /* final destination */ 233 char nop; /* one NOP to align */ 234 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */ 235 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)]; 236} ip_srcrt; 237 238static void save_rte __P((u_char *, struct in_addr)); 239 240/* 241 * IP initialization: fill in IP protocol switch table. 242 * All protocols not implemented in kernel go to raw IP protocol handler. 243 */ 244void 245ip_init() 246{ 247 register struct protosw *pr; 248 register int i; 249 250 pool_init(&ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl", 251 0, NULL, NULL, M_IPQ); 252 253 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); 254 if (pr == 0) 255 panic("ip_init"); 256 for (i = 0; i < IPPROTO_MAX; i++) 257 ip_protox[i] = pr - inetsw; 258 for (pr = inetdomain.dom_protosw; 259 pr < inetdomain.dom_protoswNPROTOSW; pr++) 260 if (pr->pr_domain->dom_family == PF_INET && 261 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 262 ip_protox[pr->pr_protocol] = pr - inetsw; 263 LIST_INIT(&ipq); 264 ip_id = time.tv_sec & 0xffff; 265 ipintrq.ifq_maxlen = ipqmaxlen; 266 TAILQ_INIT(&in_ifaddr); 267 in_ifaddrhashtbl = 268 hashinit(IN_IFADDR_HASH_SIZE, M_IFADDR, M_WAITOK, &in_ifaddrhash); 269 if (ip_mtudisc != 0) 270 ip_mtudisc_timeout_q = 271 rt_timer_queue_create(ip_mtudisc_timeout); 272#ifdef GATEWAY 273 ipflow_init(); 274#endif 275} 276 277struct sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET }; 278struct route ipforward_rt; 279 280/* 281 * Ip input routine. Checksum and byte swap header. If fragmented 282 * try to reassemble. Process options. Pass to next level. 283 */ 284void 285ipintr() 286{ 287 register struct ip *ip = NULL; 288 register struct mbuf *m; 289 register struct ipq *fp; 290 register struct in_ifaddr *ia; 291 register struct ifaddr *ifa; 292 struct ipqent *ipqe; 293 int hlen = 0, mff, len, s; 294#ifdef PFIL_HOOKS 295 struct packet_filter_hook *pfh; 296 struct mbuf *m0; 297 int rv; 298#endif /* PFIL_HOOKS */ 299 300next: 301 /* 302 * Get next datagram off input queue and get IP header 303 * in first mbuf. 304 */ 305 s = splimp(); 306 IF_DEQUEUE(&ipintrq, m); 307 splx(s); 308 if (m == 0) 309 return; 310#ifdef DIAGNOSTIC 311 if ((m->m_flags & M_PKTHDR) == 0) 312 panic("ipintr no HDR"); 313#endif 314 /* 315 * If no IP addresses have been set yet but the interfaces 316 * are receiving, can't do anything with incoming packets yet. 317 */ 318 if (in_ifaddr.tqh_first == 0) 319 goto bad; 320 ipstat.ips_total++; 321 if (m->m_len < sizeof (struct ip) && 322 (m = m_pullup(m, sizeof (struct ip))) == 0) { 323 ipstat.ips_toosmall++; 324 goto next; 325 } 326 ip = mtod(m, struct ip *); 327 if (ip->ip_v != IPVERSION) { 328 ipstat.ips_badvers++; 329 goto bad; 330 } 331 hlen = ip->ip_hl << 2; 332 if (hlen < sizeof(struct ip)) { /* minimum header length */ 333 ipstat.ips_badhlen++; 334 goto bad; 335 } 336 if (hlen > m->m_len) { 337 if ((m = m_pullup(m, hlen)) == 0) { 338 ipstat.ips_badhlen++; 339 goto next; 340 } 341 ip = mtod(m, struct ip *); 342 } 343 /* 344 * we drop packets that have a multicast address as source 345 * as wanted by rfc 1112 346 */ 347 if (IN_MULTICAST(ip->ip_src.s_addr)) { 348 goto bad; 349 } 350 351 if (in_cksum(m, hlen) != 0) { 352 ipstat.ips_badsum++; 353 goto bad; 354 } 355 356 /* 357 * Convert fields to host representation. 358 */ 359 NTOHS(ip->ip_len); 360 NTOHS(ip->ip_off); 361 len = ip->ip_len; 362 363 /* 364 * Check for additional length bogosity 365 */ 366 if (len < hlen) { 367 ipstat.ips_badlen++; 368 goto bad; 369 } 370 371 /* 372 * Check that the amount of data in the buffers 373 * is as at least much as the IP header would have us expect. 374 * Trim mbufs if longer than we expect. 375 * Drop packet if shorter than we expect. 376 */ 377 if (m->m_pkthdr.len < len) { 378 ipstat.ips_tooshort++; 379 goto bad; 380 } 381 if (m->m_pkthdr.len > len) { 382 if (m->m_len == m->m_pkthdr.len) { 383 m->m_len = len; 384 m->m_pkthdr.len = len; 385 } else 386 m_adj(m, len - m->m_pkthdr.len); 387 } 388 389 /* 390 * Assume that we can create a fast-forward IP flow entry 391 * based on this packet. 392 */ 393 m->m_flags |= M_CANFASTFWD; 394 395#ifdef PFIL_HOOKS 396 /* 397 * Run through list of hooks for input packets. If there are any 398 * filters which require that additional packets in the flow are 399 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 400 * Note that filters must _never_ set this flag, as another filter 401 * in the list may have previously cleared it. 402 */ 403 m0 = m; 404 for (pfh = pfil_hook_get(PFIL_IN); pfh; pfh = pfh->pfil_link.tqe_next) 405 if (pfh->pfil_func) { 406 rv = pfh->pfil_func(ip, hlen, m->m_pkthdr.rcvif, 0, &m0); 407 if (rv) 408 goto next; 409 m = m0; 410 if (m == NULL) 411 goto next; 412 ip = mtod(m, struct ip *); 413 } 414#endif /* PFIL_HOOKS */ 415 416 /* 417 * Process options and, if not destined for us, 418 * ship it on. ip_dooptions returns 1 when an 419 * error was detected (causing an icmp message 420 * to be sent and the original packet to be freed). 421 */ 422 ip_nhops = 0; /* for source routed packets */ 423 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 424 goto next; 425 426 /* 427 * Check our list of addresses, to see if the packet is for us. 428 */ 429 INADDR_TO_IA(ip->ip_dst, ia); 430 if (ia != NULL) 431 goto ours; 432 if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 433 for (ifa = m->m_pkthdr.rcvif->if_addrlist.tqh_first; 434 ifa != NULL; ifa = ifa->ifa_list.tqe_next) { 435 if (ifa->ifa_addr->sa_family != AF_INET) continue; 436 ia = ifatoia(ifa); 437 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 438 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 439 /* 440 * Look for all-0's host part (old broadcast addr), 441 * either for subnet or net. 442 */ 443 ip->ip_dst.s_addr == ia->ia_subnet || 444 ip->ip_dst.s_addr == ia->ia_net) 445 goto ours; 446 /* 447 * An interface with IP address zero accepts 448 * all packets that arrive on that interface. 449 */ 450 if (in_nullhost(ia->ia_addr.sin_addr)) 451 goto ours; 452 } 453 } 454 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 455 struct in_multi *inm; 456#ifdef MROUTING 457 extern struct socket *ip_mrouter; 458 459 if (m->m_flags & M_EXT) { 460 if ((m = m_pullup(m, hlen)) == 0) { 461 ipstat.ips_toosmall++; 462 goto next; 463 } 464 ip = mtod(m, struct ip *); 465 } 466 467 if (ip_mrouter) { 468 /* 469 * If we are acting as a multicast router, all 470 * incoming multicast packets are passed to the 471 * kernel-level multicast forwarding function. 472 * The packet is returned (relatively) intact; if 473 * ip_mforward() returns a non-zero value, the packet 474 * must be discarded, else it may be accepted below. 475 * 476 * (The IP ident field is put in the same byte order 477 * as expected when ip_mforward() is called from 478 * ip_output().) 479 */ 480 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 481 ipstat.ips_cantforward++; 482 m_freem(m); 483 goto next; 484 } 485 486 /* 487 * The process-level routing demon needs to receive 488 * all multicast IGMP packets, whether or not this 489 * host belongs to their destination groups. 490 */ 491 if (ip->ip_p == IPPROTO_IGMP) 492 goto ours; 493 ipstat.ips_forward++; 494 } 495#endif 496 /* 497 * See if we belong to the destination multicast group on the 498 * arrival interface. 499 */ 500 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 501 if (inm == NULL) { 502 ipstat.ips_cantforward++; 503 m_freem(m); 504 goto next; 505 } 506 goto ours; 507 } 508 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 509 in_nullhost(ip->ip_dst)) 510 goto ours; 511 512 /* 513 * Not for us; forward if possible and desirable. 514 */ 515 if (ipforwarding == 0) { 516 ipstat.ips_cantforward++; 517 m_freem(m); 518 } else 519 ip_forward(m, 0); 520 goto next; 521 522ours: 523 /* 524 * If offset or IP_MF are set, must reassemble. 525 * Otherwise, nothing need be done. 526 * (We could look in the reassembly queue to see 527 * if the packet was previously fragmented, 528 * but it's not worth the time; just let them time out.) 529 */ 530 if (ip->ip_off & ~(IP_DF|IP_RF)) { 531 /* 532 * Look for queue of fragments 533 * of this datagram. 534 */ 535 IPQ_LOCK(); 536 for (fp = ipq.lh_first; fp != NULL; fp = fp->ipq_q.le_next) 537 if (ip->ip_id == fp->ipq_id && 538 in_hosteq(ip->ip_src, fp->ipq_src) && 539 in_hosteq(ip->ip_dst, fp->ipq_dst) && 540 ip->ip_p == fp->ipq_p) 541 goto found; 542 fp = 0; 543found: 544 545 /* 546 * Adjust ip_len to not reflect header, 547 * set ipqe_mff if more fragments are expected, 548 * convert offset of this to bytes. 549 */ 550 ip->ip_len -= hlen; 551 mff = (ip->ip_off & IP_MF) != 0; 552 if (mff) { 553 /* 554 * Make sure that fragments have a data length 555 * that's a non-zero multiple of 8 bytes. 556 */ 557 if (ip->ip_len == 0 || (ip->ip_len & 0x7) != 0) { 558 ipstat.ips_badfrags++; 559 IPQ_UNLOCK(); 560 goto bad; 561 } 562 } 563 ip->ip_off <<= 3; 564 565 /* 566 * If datagram marked as having more fragments 567 * or if this is not the first fragment, 568 * attempt reassembly; if it succeeds, proceed. 569 */ 570 if (mff || ip->ip_off) { 571 ipstat.ips_fragments++; 572 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 573 if (ipqe == NULL) { 574 ipstat.ips_rcvmemdrop++; 575 IPQ_UNLOCK(); 576 goto bad; 577 } 578 ipqe->ipqe_mff = mff; 579 ipqe->ipqe_m = m; 580 ipqe->ipqe_ip = ip; 581 m = ip_reass(ipqe, fp); 582 if (m == 0) { 583 IPQ_UNLOCK(); 584 goto next; 585 } 586 ipstat.ips_reassembled++; 587 ip = mtod(m, struct ip *); 588 hlen = ip->ip_hl << 2; 589 ip->ip_len += hlen; 590 } else 591 if (fp) 592 ip_freef(fp); 593 IPQ_UNLOCK(); 594 } 595 596 /* 597 * Switch out to protocol's input routine. 598 */ 599#if IFA_STATS 600 ia->ia_ifa.ifa_data.ifad_inbytes += ip->ip_len; 601#endif 602 ipstat.ips_delivered++; 603 (*inetsw[ip_protox[ip->ip_p]].pr_input)(m, hlen); 604 goto next; 605bad: 606 m_freem(m); 607 goto next; 608} 609 610/* 611 * Take incoming datagram fragment and try to 612 * reassemble it into whole datagram. If a chain for 613 * reassembly of this datagram already exists, then it 614 * is given as fp; otherwise have to make a chain. 615 */ 616struct mbuf * 617ip_reass(ipqe, fp) 618 register struct ipqent *ipqe; 619 register struct ipq *fp; 620{ 621 register struct mbuf *m = ipqe->ipqe_m; 622 register struct ipqent *nq, *p, *q; 623 struct ip *ip; 624 struct mbuf *t; 625 int hlen = ipqe->ipqe_ip->ip_hl << 2; 626 int i, next; 627 628 IPQ_LOCK_CHECK(); 629 630 /* 631 * Presence of header sizes in mbufs 632 * would confuse code below. 633 */ 634 m->m_data += hlen; 635 m->m_len -= hlen; 636 637 /* 638 * If first fragment to arrive, create a reassembly queue. 639 */ 640 if (fp == 0) { 641 MALLOC(fp, struct ipq *, sizeof (struct ipq), 642 M_FTABLE, M_NOWAIT); 643 if (fp == NULL) 644 goto dropfrag; 645 LIST_INSERT_HEAD(&ipq, fp, ipq_q); 646 fp->ipq_ttl = IPFRAGTTL; 647 fp->ipq_p = ipqe->ipqe_ip->ip_p; 648 fp->ipq_id = ipqe->ipqe_ip->ip_id; 649 LIST_INIT(&fp->ipq_fragq); 650 fp->ipq_src = ipqe->ipqe_ip->ip_src; 651 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 652 p = NULL; 653 goto insert; 654 } 655 656 /* 657 * Find a segment which begins after this one does. 658 */ 659 for (p = NULL, q = fp->ipq_fragq.lh_first; q != NULL; 660 p = q, q = q->ipqe_q.le_next) 661 if (q->ipqe_ip->ip_off > ipqe->ipqe_ip->ip_off) 662 break; 663 664 /* 665 * If there is a preceding segment, it may provide some of 666 * our data already. If so, drop the data from the incoming 667 * segment. If it provides all of our data, drop us. 668 */ 669 if (p != NULL) { 670 i = p->ipqe_ip->ip_off + p->ipqe_ip->ip_len - 671 ipqe->ipqe_ip->ip_off; 672 if (i > 0) { 673 if (i >= ipqe->ipqe_ip->ip_len) 674 goto dropfrag; 675 m_adj(ipqe->ipqe_m, i); 676 ipqe->ipqe_ip->ip_off += i; 677 ipqe->ipqe_ip->ip_len -= i; 678 } 679 } 680 681 /* 682 * While we overlap succeeding segments trim them or, 683 * if they are completely covered, dequeue them. 684 */ 685 for (; q != NULL && ipqe->ipqe_ip->ip_off + ipqe->ipqe_ip->ip_len > 686 q->ipqe_ip->ip_off; q = nq) { 687 i = (ipqe->ipqe_ip->ip_off + ipqe->ipqe_ip->ip_len) - 688 q->ipqe_ip->ip_off; 689 if (i < q->ipqe_ip->ip_len) { 690 q->ipqe_ip->ip_len -= i; 691 q->ipqe_ip->ip_off += i; 692 m_adj(q->ipqe_m, i); 693 break; 694 } 695 nq = q->ipqe_q.le_next; 696 m_freem(q->ipqe_m); 697 LIST_REMOVE(q, ipqe_q); 698 pool_put(&ipqent_pool, q); 699 } 700 701insert: 702 /* 703 * Stick new segment in its place; 704 * check for complete reassembly. 705 */ 706 if (p == NULL) { 707 LIST_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 708 } else { 709 LIST_INSERT_AFTER(p, ipqe, ipqe_q); 710 } 711 next = 0; 712 for (p = NULL, q = fp->ipq_fragq.lh_first; q != NULL; 713 p = q, q = q->ipqe_q.le_next) { 714 if (q->ipqe_ip->ip_off != next) 715 return (0); 716 next += q->ipqe_ip->ip_len; 717 } 718 if (p->ipqe_mff) 719 return (0); 720 721 /* 722 * Reassembly is complete. Check for a bogus message size and 723 * concatenate fragments. 724 */ 725 q = fp->ipq_fragq.lh_first; 726 ip = q->ipqe_ip; 727 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 728 ipstat.ips_toolong++; 729 ip_freef(fp); 730 return (0); 731 } 732 m = q->ipqe_m; 733 t = m->m_next; 734 m->m_next = 0; 735 m_cat(m, t); 736 nq = q->ipqe_q.le_next; 737 pool_put(&ipqent_pool, q); 738 for (q = nq; q != NULL; q = nq) { 739 t = q->ipqe_m; 740 nq = q->ipqe_q.le_next; 741 pool_put(&ipqent_pool, q); 742 m_cat(m, t); 743 } 744 745 /* 746 * Create header for new ip packet by 747 * modifying header of first packet; 748 * dequeue and discard fragment reassembly header. 749 * Make header visible. 750 */ 751 ip->ip_len = next; 752 ip->ip_src = fp->ipq_src; 753 ip->ip_dst = fp->ipq_dst; 754 LIST_REMOVE(fp, ipq_q); 755 FREE(fp, M_FTABLE); 756 m->m_len += (ip->ip_hl << 2); 757 m->m_data -= (ip->ip_hl << 2); 758 /* some debugging cruft by sklower, below, will go away soon */ 759 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 760 register int plen = 0; 761 for (t = m; t; t = t->m_next) 762 plen += t->m_len; 763 m->m_pkthdr.len = plen; 764 } 765 return (m); 766 767dropfrag: 768 ipstat.ips_fragdropped++; 769 m_freem(m); 770 pool_put(&ipqent_pool, ipqe); 771 return (0); 772} 773 774/* 775 * Free a fragment reassembly header and all 776 * associated datagrams. 777 */ 778void 779ip_freef(fp) 780 struct ipq *fp; 781{ 782 register struct ipqent *q, *p; 783 784 IPQ_LOCK_CHECK(); 785 786 for (q = fp->ipq_fragq.lh_first; q != NULL; q = p) { 787 p = q->ipqe_q.le_next; 788 m_freem(q->ipqe_m); 789 LIST_REMOVE(q, ipqe_q); 790 pool_put(&ipqent_pool, q); 791 } 792 LIST_REMOVE(fp, ipq_q); 793 FREE(fp, M_FTABLE); 794} 795 796/* 797 * IP timer processing; 798 * if a timer expires on a reassembly 799 * queue, discard it. 800 */ 801void 802ip_slowtimo() 803{ 804 register struct ipq *fp, *nfp; 805 int s = splsoftnet(); 806 807 IPQ_LOCK(); 808 for (fp = ipq.lh_first; fp != NULL; fp = nfp) { 809 nfp = fp->ipq_q.le_next; 810 if (--fp->ipq_ttl == 0) { 811 ipstat.ips_fragtimeout++; 812 ip_freef(fp); 813 } 814 } 815 IPQ_UNLOCK(); 816#ifdef GATEWAY 817 ipflow_slowtimo(); 818#endif 819 splx(s); 820} 821 822/* 823 * Drain off all datagram fragments. 824 */ 825void 826ip_drain() 827{ 828 829 /* 830 * We may be called from a device's interrupt context. If 831 * the ipq is already busy, just bail out now. 832 */ 833 if (ipq_lock_try() == 0) 834 return; 835 836 while (ipq.lh_first != NULL) { 837 ipstat.ips_fragdropped++; 838 ip_freef(ipq.lh_first); 839 } 840 841 IPQ_UNLOCK(); 842} 843 844/* 845 * Do option processing on a datagram, 846 * possibly discarding it if bad options are encountered, 847 * or forwarding it if source-routed. 848 * Returns 1 if packet has been forwarded/freed, 849 * 0 if the packet should be processed further. 850 */ 851int 852ip_dooptions(m) 853 struct mbuf *m; 854{ 855 register struct ip *ip = mtod(m, struct ip *); 856 register u_char *cp; 857 register struct ip_timestamp *ipt; 858 register struct in_ifaddr *ia; 859 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 860 struct in_addr *sin, dst; 861 n_time ntime; 862 863 dst = ip->ip_dst; 864 cp = (u_char *)(ip + 1); 865 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 866 for (; cnt > 0; cnt -= optlen, cp += optlen) { 867 opt = cp[IPOPT_OPTVAL]; 868 if (opt == IPOPT_EOL) 869 break; 870 if (opt == IPOPT_NOP) 871 optlen = 1; 872 else { 873 optlen = cp[IPOPT_OLEN]; 874 if (optlen <= 0 || optlen > cnt) { 875 code = &cp[IPOPT_OLEN] - (u_char *)ip; 876 goto bad; 877 } 878 } 879 switch (opt) { 880 881 default: 882 break; 883 884 /* 885 * Source routing with record. 886 * Find interface with current destination address. 887 * If none on this machine then drop if strictly routed, 888 * or do nothing if loosely routed. 889 * Record interface address and bring up next address 890 * component. If strictly routed make sure next 891 * address is on directly accessible net. 892 */ 893 case IPOPT_LSRR: 894 case IPOPT_SSRR: 895 if (ip_allowsrcrt == 0) { 896 type = ICMP_UNREACH; 897 code = ICMP_UNREACH_NET_PROHIB; 898 goto bad; 899 } 900 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 901 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 902 goto bad; 903 } 904 ipaddr.sin_addr = ip->ip_dst; 905 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 906 if (ia == 0) { 907 if (opt == IPOPT_SSRR) { 908 type = ICMP_UNREACH; 909 code = ICMP_UNREACH_SRCFAIL; 910 goto bad; 911 } 912 /* 913 * Loose routing, and not at next destination 914 * yet; nothing to do except forward. 915 */ 916 break; 917 } 918 off--; /* 0 origin */ 919 if (off > optlen - sizeof(struct in_addr)) { 920 /* 921 * End of source route. Should be for us. 922 */ 923 save_rte(cp, ip->ip_src); 924 break; 925 } 926 /* 927 * locate outgoing interface 928 */ 929 bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr, 930 sizeof(ipaddr.sin_addr)); 931 if (opt == IPOPT_SSRR) { 932#define INA struct in_ifaddr * 933#define SA struct sockaddr * 934 ia = (INA)ifa_ifwithladdr((SA)&ipaddr); 935 } else 936 ia = ip_rtaddr(ipaddr.sin_addr); 937 if (ia == 0) { 938 type = ICMP_UNREACH; 939 code = ICMP_UNREACH_SRCFAIL; 940 goto bad; 941 } 942 ip->ip_dst = ipaddr.sin_addr; 943 bcopy((caddr_t)&ia->ia_addr.sin_addr, 944 (caddr_t)(cp + off), sizeof(struct in_addr)); 945 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 946 /* 947 * Let ip_intr's mcast routing check handle mcast pkts 948 */ 949 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 950 break; 951 952 case IPOPT_RR: 953 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 954 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 955 goto bad; 956 } 957 /* 958 * If no space remains, ignore. 959 */ 960 off--; /* 0 origin */ 961 if (off > optlen - sizeof(struct in_addr)) 962 break; 963 bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr, 964 sizeof(ipaddr.sin_addr)); 965 /* 966 * locate outgoing interface; if we're the destination, 967 * use the incoming interface (should be same). 968 */ 969 if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0 && 970 (ia = ip_rtaddr(ipaddr.sin_addr)) == 0) { 971 type = ICMP_UNREACH; 972 code = ICMP_UNREACH_HOST; 973 goto bad; 974 } 975 bcopy((caddr_t)&ia->ia_addr.sin_addr, 976 (caddr_t)(cp + off), sizeof(struct in_addr)); 977 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 978 break; 979 980 case IPOPT_TS: 981 code = cp - (u_char *)ip; 982 ipt = (struct ip_timestamp *)cp; 983 if (ipt->ipt_len < 5) 984 goto bad; 985 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 986 if (++ipt->ipt_oflw == 0) 987 goto bad; 988 break; 989 } 990 sin = (struct in_addr *)(cp + ipt->ipt_ptr - 1); 991 switch (ipt->ipt_flg) { 992 993 case IPOPT_TS_TSONLY: 994 break; 995 996 case IPOPT_TS_TSANDADDR: 997 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 998 sizeof(struct in_addr) > ipt->ipt_len) 999 goto bad; 1000 ipaddr.sin_addr = dst; 1001 ia = (INA)ifaof_ifpforaddr((SA)&ipaddr, 1002 m->m_pkthdr.rcvif); 1003 if (ia == 0) 1004 continue; 1005 bcopy((caddr_t)&ia->ia_addr.sin_addr, 1006 (caddr_t)sin, sizeof(struct in_addr)); 1007 ipt->ipt_ptr += sizeof(struct in_addr); 1008 break; 1009 1010 case IPOPT_TS_PRESPEC: 1011 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1012 sizeof(struct in_addr) > ipt->ipt_len) 1013 goto bad; 1014 bcopy((caddr_t)sin, (caddr_t)&ipaddr.sin_addr, 1015 sizeof(struct in_addr)); 1016 if (ifa_ifwithaddr((SA)&ipaddr) == 0) 1017 continue; 1018 ipt->ipt_ptr += sizeof(struct in_addr); 1019 break; 1020 1021 default: 1022 goto bad; 1023 } 1024 ntime = iptime(); 1025 bcopy((caddr_t)&ntime, (caddr_t)cp + ipt->ipt_ptr - 1, 1026 sizeof(n_time)); 1027 ipt->ipt_ptr += sizeof(n_time); 1028 } 1029 } 1030 if (forward) { 1031 if (ip_forwsrcrt == 0) { 1032 type = ICMP_UNREACH; 1033 code = ICMP_UNREACH_SRCFAIL; 1034 goto bad; 1035 } 1036 ip_forward(m, 1); 1037 return (1); 1038 } 1039 return (0); 1040bad: 1041 icmp_error(m, type, code, 0, 0); 1042 ipstat.ips_badoptions++; 1043 return (1); 1044} 1045 1046/* 1047 * Given address of next destination (final or next hop), 1048 * return internet address info of interface to be used to get there. 1049 */ 1050struct in_ifaddr * 1051ip_rtaddr(dst) 1052 struct in_addr dst; 1053{ 1054 register struct sockaddr_in *sin; 1055 1056 sin = satosin(&ipforward_rt.ro_dst); 1057 1058 if (ipforward_rt.ro_rt == 0 || !in_hosteq(dst, sin->sin_addr)) { 1059 if (ipforward_rt.ro_rt) { 1060 RTFREE(ipforward_rt.ro_rt); 1061 ipforward_rt.ro_rt = 0; 1062 } 1063 sin->sin_family = AF_INET; 1064 sin->sin_len = sizeof(*sin); 1065 sin->sin_addr = dst; 1066 1067 rtalloc(&ipforward_rt); 1068 } 1069 if (ipforward_rt.ro_rt == 0) 1070 return ((struct in_ifaddr *)0); 1071 return (ifatoia(ipforward_rt.ro_rt->rt_ifa)); 1072} 1073 1074/* 1075 * Save incoming source route for use in replies, 1076 * to be picked up later by ip_srcroute if the receiver is interested. 1077 */ 1078void 1079save_rte(option, dst) 1080 u_char *option; 1081 struct in_addr dst; 1082{ 1083 unsigned olen; 1084 1085 olen = option[IPOPT_OLEN]; 1086#ifdef DIAGNOSTIC 1087 if (ipprintfs) 1088 printf("save_rte: olen %d\n", olen); 1089#endif 1090 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1091 return; 1092 bcopy((caddr_t)option, (caddr_t)ip_srcrt.srcopt, olen); 1093 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1094 ip_srcrt.dst = dst; 1095} 1096 1097/* 1098 * Retrieve incoming source route for use in replies, 1099 * in the same form used by setsockopt. 1100 * The first hop is placed before the options, will be removed later. 1101 */ 1102struct mbuf * 1103ip_srcroute() 1104{ 1105 register struct in_addr *p, *q; 1106 register struct mbuf *m; 1107 1108 if (ip_nhops == 0) 1109 return ((struct mbuf *)0); 1110 m = m_get(M_DONTWAIT, MT_SOOPTS); 1111 if (m == 0) 1112 return ((struct mbuf *)0); 1113 1114#define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1115 1116 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1117 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1118 OPTSIZ; 1119#ifdef DIAGNOSTIC 1120 if (ipprintfs) 1121 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1122#endif 1123 1124 /* 1125 * First save first hop for return route 1126 */ 1127 p = &ip_srcrt.route[ip_nhops - 1]; 1128 *(mtod(m, struct in_addr *)) = *p--; 1129#ifdef DIAGNOSTIC 1130 if (ipprintfs) 1131 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1132#endif 1133 1134 /* 1135 * Copy option fields and padding (nop) to mbuf. 1136 */ 1137 ip_srcrt.nop = IPOPT_NOP; 1138 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1139 bcopy((caddr_t)&ip_srcrt.nop, 1140 mtod(m, caddr_t) + sizeof(struct in_addr), OPTSIZ); 1141 q = (struct in_addr *)(mtod(m, caddr_t) + 1142 sizeof(struct in_addr) + OPTSIZ); 1143#undef OPTSIZ 1144 /* 1145 * Record return path as an IP source route, 1146 * reversing the path (pointers are now aligned). 1147 */ 1148 while (p >= ip_srcrt.route) { 1149#ifdef DIAGNOSTIC 1150 if (ipprintfs) 1151 printf(" %x", ntohl(q->s_addr)); 1152#endif 1153 *q++ = *p--; 1154 } 1155 /* 1156 * Last hop goes to final destination. 1157 */ 1158 *q = ip_srcrt.dst; 1159#ifdef DIAGNOSTIC 1160 if (ipprintfs) 1161 printf(" %x\n", ntohl(q->s_addr)); 1162#endif 1163 return (m); 1164} 1165 1166/* 1167 * Strip out IP options, at higher 1168 * level protocol in the kernel. 1169 * Second argument is buffer to which options 1170 * will be moved, and return value is their length. 1171 * XXX should be deleted; last arg currently ignored. 1172 */ 1173void 1174ip_stripoptions(m, mopt) 1175 register struct mbuf *m; 1176 struct mbuf *mopt; 1177{ 1178 register int i; 1179 struct ip *ip = mtod(m, struct ip *); 1180 register caddr_t opts; 1181 int olen; 1182 1183 olen = (ip->ip_hl << 2) - sizeof (struct ip); 1184 opts = (caddr_t)(ip + 1); 1185 i = m->m_len - (sizeof (struct ip) + olen); 1186 bcopy(opts + olen, opts, (unsigned)i); 1187 m->m_len -= olen; 1188 if (m->m_flags & M_PKTHDR) 1189 m->m_pkthdr.len -= olen; 1190 ip->ip_len -= olen; 1191 ip->ip_hl = sizeof (struct ip) >> 2; 1192} 1193 1194int inetctlerrmap[PRC_NCMDS] = { 1195 0, 0, 0, 0, 1196 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1197 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1198 EMSGSIZE, EHOSTUNREACH, 0, 0, 1199 0, 0, 0, 0, 1200 ENOPROTOOPT 1201}; 1202 1203/* 1204 * Forward a packet. If some error occurs return the sender 1205 * an icmp packet. Note we can't always generate a meaningful 1206 * icmp message because icmp doesn't have a large enough repertoire 1207 * of codes and types. 1208 * 1209 * If not forwarding, just drop the packet. This could be confusing 1210 * if ipforwarding was zero but some routing protocol was advancing 1211 * us as a gateway to somewhere. However, we must let the routing 1212 * protocol deal with that. 1213 * 1214 * The srcrt parameter indicates whether the packet is being forwarded 1215 * via a source route. 1216 */ 1217void 1218ip_forward(m, srcrt) 1219 struct mbuf *m; 1220 int srcrt; 1221{ 1222 register struct ip *ip = mtod(m, struct ip *); 1223 register struct sockaddr_in *sin; 1224 register struct rtentry *rt; 1225 int error, type = 0, code = 0; 1226 struct mbuf *mcopy; 1227 n_long dest; 1228 struct ifnet *destifp; 1229 1230 dest = 0; 1231#ifdef DIAGNOSTIC 1232 if (ipprintfs) 1233 printf("forward: src %2.2x dst %2.2x ttl %x\n", 1234 ntohl(ip->ip_src.s_addr), 1235 ntohl(ip->ip_dst.s_addr), ip->ip_ttl); 1236#endif 1237 if (m->m_flags & M_BCAST || in_canforward(ip->ip_dst) == 0) { 1238 ipstat.ips_cantforward++; 1239 m_freem(m); 1240 return; 1241 } 1242 if (ip->ip_ttl <= IPTTLDEC) { 1243 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1244 return; 1245 } 1246 ip->ip_ttl -= IPTTLDEC; 1247 1248 sin = satosin(&ipforward_rt.ro_dst); 1249 if ((rt = ipforward_rt.ro_rt) == 0 || 1250 !in_hosteq(ip->ip_dst, sin->sin_addr)) { 1251 if (ipforward_rt.ro_rt) { 1252 RTFREE(ipforward_rt.ro_rt); 1253 ipforward_rt.ro_rt = 0; 1254 } 1255 sin->sin_family = AF_INET; 1256 sin->sin_len = sizeof(struct sockaddr_in); 1257 sin->sin_addr = ip->ip_dst; 1258 1259 rtalloc(&ipforward_rt); 1260 if (ipforward_rt.ro_rt == 0) { 1261 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0); 1262 return; 1263 } 1264 rt = ipforward_rt.ro_rt; 1265 } 1266 1267 /* 1268 * Save at most 68 bytes of the packet in case 1269 * we need to generate an ICMP message to the src. 1270 */ 1271 mcopy = m_copy(m, 0, imin((int)ip->ip_len, 68)); 1272 1273 /* 1274 * If forwarding packet using same interface that it came in on, 1275 * perhaps should send a redirect to sender to shortcut a hop. 1276 * Only send redirect if source is sending directly to us, 1277 * and if packet was not source routed (or has any options). 1278 * Also, don't send redirect if forwarding using a default route 1279 * or a route modified by a redirect. 1280 */ 1281 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1282 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1283 !in_nullhost(satosin(rt_key(rt))->sin_addr) && 1284 ipsendredirects && !srcrt) { 1285 if (rt->rt_ifa && 1286 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1287 ifatoia(rt->rt_ifa)->ia_subnet) { 1288 if (rt->rt_flags & RTF_GATEWAY) 1289 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1290 else 1291 dest = ip->ip_dst.s_addr; 1292 /* 1293 * Router requirements says to only send host 1294 * redirects. 1295 */ 1296 type = ICMP_REDIRECT; 1297 code = ICMP_REDIRECT_HOST; 1298#ifdef DIAGNOSTIC 1299 if (ipprintfs) 1300 printf("redirect (%d) to %x\n", code, 1301 (u_int32_t)dest); 1302#endif 1303 } 1304 } 1305 1306 error = ip_output(m, (struct mbuf *)0, &ipforward_rt, 1307 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 0); 1308 if (error) 1309 ipstat.ips_cantforward++; 1310 else { 1311 ipstat.ips_forward++; 1312 if (type) 1313 ipstat.ips_redirectsent++; 1314 else { 1315 if (mcopy) { 1316#ifdef GATEWAY 1317 if (mcopy->m_flags & M_CANFASTFWD) 1318 ipflow_create(&ipforward_rt, mcopy); 1319#endif 1320 m_freem(mcopy); 1321 } 1322 return; 1323 } 1324 } 1325 if (mcopy == NULL) 1326 return; 1327 destifp = NULL; 1328 1329 switch (error) { 1330 1331 case 0: /* forwarded, but need redirect */ 1332 /* type, code set above */ 1333 break; 1334 1335 case ENETUNREACH: /* shouldn't happen, checked above */ 1336 case EHOSTUNREACH: 1337 case ENETDOWN: 1338 case EHOSTDOWN: 1339 default: 1340 type = ICMP_UNREACH; 1341 code = ICMP_UNREACH_HOST; 1342 break; 1343 1344 case EMSGSIZE: 1345 type = ICMP_UNREACH; 1346 code = ICMP_UNREACH_NEEDFRAG; 1347 if (ipforward_rt.ro_rt) 1348 destifp = ipforward_rt.ro_rt->rt_ifp; 1349 ipstat.ips_cantfrag++; 1350 break; 1351 1352 case ENOBUFS: 1353 type = ICMP_SOURCEQUENCH; 1354 code = 0; 1355 break; 1356 } 1357 icmp_error(mcopy, type, code, dest, destifp); 1358} 1359 1360void 1361ip_savecontrol(inp, mp, ip, m) 1362 register struct inpcb *inp; 1363 register struct mbuf **mp; 1364 register struct ip *ip; 1365 register struct mbuf *m; 1366{ 1367 1368 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 1369 struct timeval tv; 1370 1371 microtime(&tv); 1372 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1373 SCM_TIMESTAMP, SOL_SOCKET); 1374 if (*mp) 1375 mp = &(*mp)->m_next; 1376 } 1377 if (inp->inp_flags & INP_RECVDSTADDR) { 1378 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst, 1379 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 1380 if (*mp) 1381 mp = &(*mp)->m_next; 1382 } 1383#ifdef notyet 1384 /* 1385 * XXX 1386 * Moving these out of udp_input() made them even more broken 1387 * than they already were. 1388 * - fenner@parc.xerox.com 1389 */ 1390 /* options were tossed already */ 1391 if (inp->inp_flags & INP_RECVOPTS) { 1392 *mp = sbcreatecontrol((caddr_t) opts_deleted_above, 1393 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 1394 if (*mp) 1395 mp = &(*mp)->m_next; 1396 } 1397 /* ip_srcroute doesn't do what we want here, need to fix */ 1398 if (inp->inp_flags & INP_RECVRETOPTS) { 1399 *mp = sbcreatecontrol((caddr_t) ip_srcroute(), 1400 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 1401 if (*mp) 1402 mp = &(*mp)->m_next; 1403 } 1404#endif 1405 if (inp->inp_flags & INP_RECVIF) { 1406 struct sockaddr_dl sdl; 1407 1408 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]); 1409 sdl.sdl_family = AF_LINK; 1410 sdl.sdl_index = m->m_pkthdr.rcvif ? 1411 m->m_pkthdr.rcvif->if_index : 0; 1412 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0; 1413 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len, 1414 IP_RECVIF, IPPROTO_IP); 1415 if (*mp) 1416 mp = &(*mp)->m_next; 1417 } 1418} 1419 1420int 1421ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 1422 int *name; 1423 u_int namelen; 1424 void *oldp; 1425 size_t *oldlenp; 1426 void *newp; 1427 size_t newlen; 1428{ 1429 extern int subnetsarelocal, hostzeroisbroadcast; 1430 1431 int error, old; 1432 1433 /* All sysctl names at this level are terminal. */ 1434 if (namelen != 1) 1435 return (ENOTDIR); 1436 1437 switch (name[0]) { 1438 case IPCTL_FORWARDING: 1439 return (sysctl_int(oldp, oldlenp, newp, newlen, &ipforwarding)); 1440 case IPCTL_SENDREDIRECTS: 1441 return (sysctl_int(oldp, oldlenp, newp, newlen, 1442 &ipsendredirects)); 1443 case IPCTL_DEFTTL: 1444 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_defttl)); 1445#ifdef notyet 1446 case IPCTL_DEFMTU: 1447 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu)); 1448#endif 1449 case IPCTL_FORWSRCRT: 1450 /* Don't allow this to change in a secure environment. */ 1451 if (securelevel > 0) 1452 return (sysctl_rdint(oldp, oldlenp, newp, 1453 ip_forwsrcrt)); 1454 else 1455 return (sysctl_int(oldp, oldlenp, newp, newlen, 1456 &ip_forwsrcrt)); 1457 case IPCTL_DIRECTEDBCAST: 1458 return (sysctl_int(oldp, oldlenp, newp, newlen, 1459 &ip_directedbcast)); 1460 case IPCTL_ALLOWSRCRT: 1461 return (sysctl_int(oldp, oldlenp, newp, newlen, 1462 &ip_allowsrcrt)); 1463 case IPCTL_SUBNETSARELOCAL: 1464 return (sysctl_int(oldp, oldlenp, newp, newlen, 1465 &subnetsarelocal)); 1466 case IPCTL_MTUDISC: 1467 error = sysctl_int(oldp, oldlenp, newp, newlen, 1468 &ip_mtudisc); 1469 if (ip_mtudisc != 0 && ip_mtudisc_timeout_q == NULL) { 1470 ip_mtudisc_timeout_q = 1471 rt_timer_queue_create(ip_mtudisc_timeout); 1472 } else if (ip_mtudisc == 0 && ip_mtudisc_timeout_q != NULL) { 1473 rt_timer_queue_destroy(ip_mtudisc_timeout_q, TRUE); 1474 ip_mtudisc_timeout_q = NULL; 1475 } 1476 return error; 1477 case IPCTL_ANONPORTMIN: 1478 old = anonportmin; 1479 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmin); 1480 if (anonportmin >= anonportmax || anonportmin > 65535 1481#ifndef IPNOPRIVPORTS 1482 || anonportmin < IPPORT_RESERVED 1483#endif 1484 ) { 1485 anonportmin = old; 1486 return (EINVAL); 1487 } 1488 return (error); 1489 case IPCTL_ANONPORTMAX: 1490 old = anonportmax; 1491 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmax); 1492 if (anonportmin >= anonportmax || anonportmax > 65535 1493#ifndef IPNOPRIVPORTS 1494 || anonportmax < IPPORT_RESERVED 1495#endif 1496 ) { 1497 anonportmax = old; 1498 return (EINVAL); 1499 } 1500 return (error); 1501 case IPCTL_MTUDISCTIMEOUT: 1502 error = sysctl_int(oldp, oldlenp, newp, newlen, 1503 &ip_mtudisc_timeout); 1504 if (ip_mtudisc_timeout_q != NULL) 1505 rt_timer_queue_change(ip_mtudisc_timeout_q, 1506 ip_mtudisc_timeout); 1507 return (error); 1508#ifdef GATEWAY 1509 case IPCTL_MAXFLOWS: 1510 { 1511 int s; 1512 1513 error = sysctl_int(oldp, oldlenp, newp, newlen, 1514 &ip_maxflows); 1515 s = splsoftnet(); 1516 ipflow_reap(0); 1517 splx(s); 1518 return (error); 1519 } 1520#endif 1521 case IPCTL_HOSTZEROBROADCAST: 1522 return (sysctl_int(oldp, oldlenp, newp, newlen, 1523 &hostzeroisbroadcast)); 1524 1525 default: 1526 return (EOPNOTSUPP); 1527 } 1528 /* NOTREACHED */ 1529} 1530