ip_input.c revision 1.84
1/* $NetBSD: ip_input.c,v 1.84 1999/04/07 05:34:32 proff 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 if (in_cksum(m, hlen) != 0) { 344 ipstat.ips_badsum++; 345 goto bad; 346 } 347 348 /* 349 * Convert fields to host representation. 350 */ 351 NTOHS(ip->ip_len); 352 NTOHS(ip->ip_off); 353 len = ip->ip_len; 354 355 /* 356 * Check for additional length bogosity 357 */ 358 if (len < hlen) { 359 ipstat.ips_badlen++; 360 goto bad; 361 } 362 363 /* 364 * Check that the amount of data in the buffers 365 * is as at least much as the IP header would have us expect. 366 * Trim mbufs if longer than we expect. 367 * Drop packet if shorter than we expect. 368 */ 369 if (m->m_pkthdr.len < len) { 370 ipstat.ips_tooshort++; 371 goto bad; 372 } 373 if (m->m_pkthdr.len > len) { 374 if (m->m_len == m->m_pkthdr.len) { 375 m->m_len = len; 376 m->m_pkthdr.len = len; 377 } else 378 m_adj(m, len - m->m_pkthdr.len); 379 } 380 381 /* 382 * Assume that we can create a fast-forward IP flow entry 383 * based on this packet. 384 */ 385 m->m_flags |= M_CANFASTFWD; 386 387#ifdef PFIL_HOOKS 388 /* 389 * Run through list of hooks for input packets. If there are any 390 * filters which require that additional packets in the flow are 391 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 392 * Note that filters must _never_ set this flag, as another filter 393 * in the list may have previously cleared it. 394 */ 395 m0 = m; 396 for (pfh = pfil_hook_get(PFIL_IN); pfh; pfh = pfh->pfil_link.tqe_next) 397 if (pfh->pfil_func) { 398 rv = pfh->pfil_func(ip, hlen, m->m_pkthdr.rcvif, 0, &m0); 399 if (rv) 400 goto next; 401 m = m0; 402 if (m == NULL) 403 goto next; 404 ip = mtod(m, struct ip *); 405 } 406#endif /* PFIL_HOOKS */ 407 408 /* 409 * Process options and, if not destined for us, 410 * ship it on. ip_dooptions returns 1 when an 411 * error was detected (causing an icmp message 412 * to be sent and the original packet to be freed). 413 */ 414 ip_nhops = 0; /* for source routed packets */ 415 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 416 goto next; 417 418 /* 419 * Check our list of addresses, to see if the packet is for us. 420 */ 421 INADDR_TO_IA(ip->ip_dst, ia); 422 if (ia != NULL) { 423 if (ia->ia_ifp->if_flags & IFF_UP) 424 goto ours; 425 } 426 if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 427 for (ifa = m->m_pkthdr.rcvif->if_addrlist.tqh_first; 428 ifa != NULL; ifa = ifa->ifa_list.tqe_next) { 429 if (ifa->ifa_addr->sa_family != AF_INET) continue; 430 ia = ifatoia(ifa); 431 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 432 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 433 /* 434 * Look for all-0's host part (old broadcast addr), 435 * either for subnet or net. 436 */ 437 ip->ip_dst.s_addr == ia->ia_subnet || 438 ip->ip_dst.s_addr == ia->ia_net) 439 goto ours; 440 /* 441 * An interface with IP address zero accepts 442 * all packets that arrive on that interface. 443 */ 444 if (in_nullhost(ia->ia_addr.sin_addr)) 445 goto ours; 446 } 447 } 448 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 449 struct in_multi *inm; 450#ifdef MROUTING 451 extern struct socket *ip_mrouter; 452 453 if (m->m_flags & M_EXT) { 454 if ((m = m_pullup(m, hlen)) == 0) { 455 ipstat.ips_toosmall++; 456 goto next; 457 } 458 ip = mtod(m, struct ip *); 459 } 460 461 if (ip_mrouter) { 462 /* 463 * If we are acting as a multicast router, all 464 * incoming multicast packets are passed to the 465 * kernel-level multicast forwarding function. 466 * The packet is returned (relatively) intact; if 467 * ip_mforward() returns a non-zero value, the packet 468 * must be discarded, else it may be accepted below. 469 * 470 * (The IP ident field is put in the same byte order 471 * as expected when ip_mforward() is called from 472 * ip_output().) 473 */ 474 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 475 ipstat.ips_cantforward++; 476 m_freem(m); 477 goto next; 478 } 479 480 /* 481 * The process-level routing demon needs to receive 482 * all multicast IGMP packets, whether or not this 483 * host belongs to their destination groups. 484 */ 485 if (ip->ip_p == IPPROTO_IGMP) 486 goto ours; 487 ipstat.ips_forward++; 488 } 489#endif 490 /* 491 * See if we belong to the destination multicast group on the 492 * arrival interface. 493 */ 494 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 495 if (inm == NULL) { 496 ipstat.ips_cantforward++; 497 m_freem(m); 498 goto next; 499 } 500 goto ours; 501 } 502 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 503 in_nullhost(ip->ip_dst)) 504 goto ours; 505 506 /* 507 * Not for us; forward if possible and desirable. 508 */ 509 if (ipforwarding == 0) { 510 ipstat.ips_cantforward++; 511 m_freem(m); 512 } else 513 ip_forward(m, 0); 514 goto next; 515 516ours: 517 /* 518 * If offset or IP_MF are set, must reassemble. 519 * Otherwise, nothing need be done. 520 * (We could look in the reassembly queue to see 521 * if the packet was previously fragmented, 522 * but it's not worth the time; just let them time out.) 523 */ 524 if (ip->ip_off & ~(IP_DF|IP_RF)) { 525 /* 526 * Look for queue of fragments 527 * of this datagram. 528 */ 529 IPQ_LOCK(); 530 for (fp = ipq.lh_first; fp != NULL; fp = fp->ipq_q.le_next) 531 if (ip->ip_id == fp->ipq_id && 532 in_hosteq(ip->ip_src, fp->ipq_src) && 533 in_hosteq(ip->ip_dst, fp->ipq_dst) && 534 ip->ip_p == fp->ipq_p) 535 goto found; 536 fp = 0; 537found: 538 539 /* 540 * Adjust ip_len to not reflect header, 541 * set ipqe_mff if more fragments are expected, 542 * convert offset of this to bytes. 543 */ 544 ip->ip_len -= hlen; 545 mff = (ip->ip_off & IP_MF) != 0; 546 if (mff) { 547 /* 548 * Make sure that fragments have a data length 549 * that's a non-zero multiple of 8 bytes. 550 */ 551 if (ip->ip_len == 0 || (ip->ip_len & 0x7) != 0) { 552 ipstat.ips_badfrags++; 553 IPQ_UNLOCK(); 554 goto bad; 555 } 556 } 557 ip->ip_off <<= 3; 558 559 /* 560 * If datagram marked as having more fragments 561 * or if this is not the first fragment, 562 * attempt reassembly; if it succeeds, proceed. 563 */ 564 if (mff || ip->ip_off) { 565 ipstat.ips_fragments++; 566 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 567 if (ipqe == NULL) { 568 ipstat.ips_rcvmemdrop++; 569 IPQ_UNLOCK(); 570 goto bad; 571 } 572 ipqe->ipqe_mff = mff; 573 ipqe->ipqe_m = m; 574 ipqe->ipqe_ip = ip; 575 m = ip_reass(ipqe, fp); 576 if (m == 0) { 577 IPQ_UNLOCK(); 578 goto next; 579 } 580 ipstat.ips_reassembled++; 581 ip = mtod(m, struct ip *); 582 hlen = ip->ip_hl << 2; 583 ip->ip_len += hlen; 584 } else 585 if (fp) 586 ip_freef(fp); 587 IPQ_UNLOCK(); 588 } 589 590 /* 591 * Switch out to protocol's input routine. 592 */ 593#if IFA_STATS 594 ia->ia_ifa.ifa_data.ifad_inbytes += ip->ip_len; 595#endif 596 ipstat.ips_delivered++; 597 (*inetsw[ip_protox[ip->ip_p]].pr_input)(m, hlen); 598 goto next; 599bad: 600 m_freem(m); 601 goto next; 602} 603 604/* 605 * Take incoming datagram fragment and try to 606 * reassemble it into whole datagram. If a chain for 607 * reassembly of this datagram already exists, then it 608 * is given as fp; otherwise have to make a chain. 609 */ 610struct mbuf * 611ip_reass(ipqe, fp) 612 register struct ipqent *ipqe; 613 register struct ipq *fp; 614{ 615 register struct mbuf *m = ipqe->ipqe_m; 616 register struct ipqent *nq, *p, *q; 617 struct ip *ip; 618 struct mbuf *t; 619 int hlen = ipqe->ipqe_ip->ip_hl << 2; 620 int i, next; 621 622 IPQ_LOCK_CHECK(); 623 624 /* 625 * Presence of header sizes in mbufs 626 * would confuse code below. 627 */ 628 m->m_data += hlen; 629 m->m_len -= hlen; 630 631 /* 632 * If first fragment to arrive, create a reassembly queue. 633 */ 634 if (fp == 0) { 635 MALLOC(fp, struct ipq *, sizeof (struct ipq), 636 M_FTABLE, M_NOWAIT); 637 if (fp == NULL) 638 goto dropfrag; 639 LIST_INSERT_HEAD(&ipq, fp, ipq_q); 640 fp->ipq_ttl = IPFRAGTTL; 641 fp->ipq_p = ipqe->ipqe_ip->ip_p; 642 fp->ipq_id = ipqe->ipqe_ip->ip_id; 643 LIST_INIT(&fp->ipq_fragq); 644 fp->ipq_src = ipqe->ipqe_ip->ip_src; 645 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 646 p = NULL; 647 goto insert; 648 } 649 650 /* 651 * Find a segment which begins after this one does. 652 */ 653 for (p = NULL, q = fp->ipq_fragq.lh_first; q != NULL; 654 p = q, q = q->ipqe_q.le_next) 655 if (q->ipqe_ip->ip_off > ipqe->ipqe_ip->ip_off) 656 break; 657 658 /* 659 * If there is a preceding segment, it may provide some of 660 * our data already. If so, drop the data from the incoming 661 * segment. If it provides all of our data, drop us. 662 */ 663 if (p != NULL) { 664 i = p->ipqe_ip->ip_off + p->ipqe_ip->ip_len - 665 ipqe->ipqe_ip->ip_off; 666 if (i > 0) { 667 if (i >= ipqe->ipqe_ip->ip_len) 668 goto dropfrag; 669 m_adj(ipqe->ipqe_m, i); 670 ipqe->ipqe_ip->ip_off += i; 671 ipqe->ipqe_ip->ip_len -= i; 672 } 673 } 674 675 /* 676 * While we overlap succeeding segments trim them or, 677 * if they are completely covered, dequeue them. 678 */ 679 for (; q != NULL && ipqe->ipqe_ip->ip_off + ipqe->ipqe_ip->ip_len > 680 q->ipqe_ip->ip_off; q = nq) { 681 i = (ipqe->ipqe_ip->ip_off + ipqe->ipqe_ip->ip_len) - 682 q->ipqe_ip->ip_off; 683 if (i < q->ipqe_ip->ip_len) { 684 q->ipqe_ip->ip_len -= i; 685 q->ipqe_ip->ip_off += i; 686 m_adj(q->ipqe_m, i); 687 break; 688 } 689 nq = q->ipqe_q.le_next; 690 m_freem(q->ipqe_m); 691 LIST_REMOVE(q, ipqe_q); 692 pool_put(&ipqent_pool, q); 693 } 694 695insert: 696 /* 697 * Stick new segment in its place; 698 * check for complete reassembly. 699 */ 700 if (p == NULL) { 701 LIST_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 702 } else { 703 LIST_INSERT_AFTER(p, ipqe, ipqe_q); 704 } 705 next = 0; 706 for (p = NULL, q = fp->ipq_fragq.lh_first; q != NULL; 707 p = q, q = q->ipqe_q.le_next) { 708 if (q->ipqe_ip->ip_off != next) 709 return (0); 710 next += q->ipqe_ip->ip_len; 711 } 712 if (p->ipqe_mff) 713 return (0); 714 715 /* 716 * Reassembly is complete. Check for a bogus message size and 717 * concatenate fragments. 718 */ 719 q = fp->ipq_fragq.lh_first; 720 ip = q->ipqe_ip; 721 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 722 ipstat.ips_toolong++; 723 ip_freef(fp); 724 return (0); 725 } 726 m = q->ipqe_m; 727 t = m->m_next; 728 m->m_next = 0; 729 m_cat(m, t); 730 nq = q->ipqe_q.le_next; 731 pool_put(&ipqent_pool, q); 732 for (q = nq; q != NULL; q = nq) { 733 t = q->ipqe_m; 734 nq = q->ipqe_q.le_next; 735 pool_put(&ipqent_pool, q); 736 m_cat(m, t); 737 } 738 739 /* 740 * Create header for new ip packet by 741 * modifying header of first packet; 742 * dequeue and discard fragment reassembly header. 743 * Make header visible. 744 */ 745 ip->ip_len = next; 746 ip->ip_src = fp->ipq_src; 747 ip->ip_dst = fp->ipq_dst; 748 LIST_REMOVE(fp, ipq_q); 749 FREE(fp, M_FTABLE); 750 m->m_len += (ip->ip_hl << 2); 751 m->m_data -= (ip->ip_hl << 2); 752 /* some debugging cruft by sklower, below, will go away soon */ 753 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 754 register int plen = 0; 755 for (t = m; t; t = t->m_next) 756 plen += t->m_len; 757 m->m_pkthdr.len = plen; 758 } 759 return (m); 760 761dropfrag: 762 ipstat.ips_fragdropped++; 763 m_freem(m); 764 pool_put(&ipqent_pool, ipqe); 765 return (0); 766} 767 768/* 769 * Free a fragment reassembly header and all 770 * associated datagrams. 771 */ 772void 773ip_freef(fp) 774 struct ipq *fp; 775{ 776 register struct ipqent *q, *p; 777 778 IPQ_LOCK_CHECK(); 779 780 for (q = fp->ipq_fragq.lh_first; q != NULL; q = p) { 781 p = q->ipqe_q.le_next; 782 m_freem(q->ipqe_m); 783 LIST_REMOVE(q, ipqe_q); 784 pool_put(&ipqent_pool, q); 785 } 786 LIST_REMOVE(fp, ipq_q); 787 FREE(fp, M_FTABLE); 788} 789 790/* 791 * IP timer processing; 792 * if a timer expires on a reassembly 793 * queue, discard it. 794 */ 795void 796ip_slowtimo() 797{ 798 register struct ipq *fp, *nfp; 799 int s = splsoftnet(); 800 801 IPQ_LOCK(); 802 for (fp = ipq.lh_first; fp != NULL; fp = nfp) { 803 nfp = fp->ipq_q.le_next; 804 if (--fp->ipq_ttl == 0) { 805 ipstat.ips_fragtimeout++; 806 ip_freef(fp); 807 } 808 } 809 IPQ_UNLOCK(); 810#ifdef GATEWAY 811 ipflow_slowtimo(); 812#endif 813 splx(s); 814} 815 816/* 817 * Drain off all datagram fragments. 818 */ 819void 820ip_drain() 821{ 822 823 /* 824 * We may be called from a device's interrupt context. If 825 * the ipq is already busy, just bail out now. 826 */ 827 if (ipq_lock_try() == 0) 828 return; 829 830 while (ipq.lh_first != NULL) { 831 ipstat.ips_fragdropped++; 832 ip_freef(ipq.lh_first); 833 } 834 835 IPQ_UNLOCK(); 836} 837 838/* 839 * Do option processing on a datagram, 840 * possibly discarding it if bad options are encountered, 841 * or forwarding it if source-routed. 842 * Returns 1 if packet has been forwarded/freed, 843 * 0 if the packet should be processed further. 844 */ 845int 846ip_dooptions(m) 847 struct mbuf *m; 848{ 849 register struct ip *ip = mtod(m, struct ip *); 850 register u_char *cp; 851 register struct ip_timestamp *ipt; 852 register struct in_ifaddr *ia; 853 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 854 struct in_addr *sin, dst; 855 n_time ntime; 856 857 dst = ip->ip_dst; 858 cp = (u_char *)(ip + 1); 859 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 860 for (; cnt > 0; cnt -= optlen, cp += optlen) { 861 opt = cp[IPOPT_OPTVAL]; 862 if (opt == IPOPT_EOL) 863 break; 864 if (opt == IPOPT_NOP) 865 optlen = 1; 866 else { 867 optlen = cp[IPOPT_OLEN]; 868 if (optlen <= 0 || optlen > cnt) { 869 code = &cp[IPOPT_OLEN] - (u_char *)ip; 870 goto bad; 871 } 872 } 873 switch (opt) { 874 875 default: 876 break; 877 878 /* 879 * Source routing with record. 880 * Find interface with current destination address. 881 * If none on this machine then drop if strictly routed, 882 * or do nothing if loosely routed. 883 * Record interface address and bring up next address 884 * component. If strictly routed make sure next 885 * address is on directly accessible net. 886 */ 887 case IPOPT_LSRR: 888 case IPOPT_SSRR: 889 if (ip_allowsrcrt == 0) { 890 type = ICMP_UNREACH; 891 code = ICMP_UNREACH_NET_PROHIB; 892 goto bad; 893 } 894 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 895 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 896 goto bad; 897 } 898 ipaddr.sin_addr = ip->ip_dst; 899 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 900 if (ia == 0) { 901 if (opt == IPOPT_SSRR) { 902 type = ICMP_UNREACH; 903 code = ICMP_UNREACH_SRCFAIL; 904 goto bad; 905 } 906 /* 907 * Loose routing, and not at next destination 908 * yet; nothing to do except forward. 909 */ 910 break; 911 } 912 off--; /* 0 origin */ 913 if (off > optlen - sizeof(struct in_addr)) { 914 /* 915 * End of source route. Should be for us. 916 */ 917 save_rte(cp, ip->ip_src); 918 break; 919 } 920 /* 921 * locate outgoing interface 922 */ 923 bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr, 924 sizeof(ipaddr.sin_addr)); 925 if (opt == IPOPT_SSRR) { 926#define INA struct in_ifaddr * 927#define SA struct sockaddr * 928 ia = (INA)ifa_ifwithladdr((SA)&ipaddr); 929 } else 930 ia = ip_rtaddr(ipaddr.sin_addr); 931 if (ia == 0) { 932 type = ICMP_UNREACH; 933 code = ICMP_UNREACH_SRCFAIL; 934 goto bad; 935 } 936 ip->ip_dst = ipaddr.sin_addr; 937 bcopy((caddr_t)&ia->ia_addr.sin_addr, 938 (caddr_t)(cp + off), sizeof(struct in_addr)); 939 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 940 /* 941 * Let ip_intr's mcast routing check handle mcast pkts 942 */ 943 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 944 break; 945 946 case IPOPT_RR: 947 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 948 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 949 goto bad; 950 } 951 /* 952 * If no space remains, ignore. 953 */ 954 off--; /* 0 origin */ 955 if (off > optlen - sizeof(struct in_addr)) 956 break; 957 bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr, 958 sizeof(ipaddr.sin_addr)); 959 /* 960 * locate outgoing interface; if we're the destination, 961 * use the incoming interface (should be same). 962 */ 963 if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0 && 964 (ia = ip_rtaddr(ipaddr.sin_addr)) == 0) { 965 type = ICMP_UNREACH; 966 code = ICMP_UNREACH_HOST; 967 goto bad; 968 } 969 bcopy((caddr_t)&ia->ia_addr.sin_addr, 970 (caddr_t)(cp + off), sizeof(struct in_addr)); 971 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 972 break; 973 974 case IPOPT_TS: 975 code = cp - (u_char *)ip; 976 ipt = (struct ip_timestamp *)cp; 977 if (ipt->ipt_len < 5) 978 goto bad; 979 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 980 if (++ipt->ipt_oflw == 0) 981 goto bad; 982 break; 983 } 984 sin = (struct in_addr *)(cp + ipt->ipt_ptr - 1); 985 switch (ipt->ipt_flg) { 986 987 case IPOPT_TS_TSONLY: 988 break; 989 990 case IPOPT_TS_TSANDADDR: 991 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 992 sizeof(struct in_addr) > ipt->ipt_len) 993 goto bad; 994 ipaddr.sin_addr = dst; 995 ia = (INA)ifaof_ifpforaddr((SA)&ipaddr, 996 m->m_pkthdr.rcvif); 997 if (ia == 0) 998 continue; 999 bcopy((caddr_t)&ia->ia_addr.sin_addr, 1000 (caddr_t)sin, sizeof(struct in_addr)); 1001 ipt->ipt_ptr += sizeof(struct in_addr); 1002 break; 1003 1004 case IPOPT_TS_PRESPEC: 1005 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 1006 sizeof(struct in_addr) > ipt->ipt_len) 1007 goto bad; 1008 bcopy((caddr_t)sin, (caddr_t)&ipaddr.sin_addr, 1009 sizeof(struct in_addr)); 1010 if (ifa_ifwithaddr((SA)&ipaddr) == 0) 1011 continue; 1012 ipt->ipt_ptr += sizeof(struct in_addr); 1013 break; 1014 1015 default: 1016 goto bad; 1017 } 1018 ntime = iptime(); 1019 bcopy((caddr_t)&ntime, (caddr_t)cp + ipt->ipt_ptr - 1, 1020 sizeof(n_time)); 1021 ipt->ipt_ptr += sizeof(n_time); 1022 } 1023 } 1024 if (forward) { 1025 if (ip_forwsrcrt == 0) { 1026 type = ICMP_UNREACH; 1027 code = ICMP_UNREACH_SRCFAIL; 1028 goto bad; 1029 } 1030 ip_forward(m, 1); 1031 return (1); 1032 } 1033 return (0); 1034bad: 1035 icmp_error(m, type, code, 0, 0); 1036 ipstat.ips_badoptions++; 1037 return (1); 1038} 1039 1040/* 1041 * Given address of next destination (final or next hop), 1042 * return internet address info of interface to be used to get there. 1043 */ 1044struct in_ifaddr * 1045ip_rtaddr(dst) 1046 struct in_addr dst; 1047{ 1048 register struct sockaddr_in *sin; 1049 1050 sin = satosin(&ipforward_rt.ro_dst); 1051 1052 if (ipforward_rt.ro_rt == 0 || !in_hosteq(dst, sin->sin_addr)) { 1053 if (ipforward_rt.ro_rt) { 1054 RTFREE(ipforward_rt.ro_rt); 1055 ipforward_rt.ro_rt = 0; 1056 } 1057 sin->sin_family = AF_INET; 1058 sin->sin_len = sizeof(*sin); 1059 sin->sin_addr = dst; 1060 1061 rtalloc(&ipforward_rt); 1062 } 1063 if (ipforward_rt.ro_rt == 0) 1064 return ((struct in_ifaddr *)0); 1065 return (ifatoia(ipforward_rt.ro_rt->rt_ifa)); 1066} 1067 1068/* 1069 * Save incoming source route for use in replies, 1070 * to be picked up later by ip_srcroute if the receiver is interested. 1071 */ 1072void 1073save_rte(option, dst) 1074 u_char *option; 1075 struct in_addr dst; 1076{ 1077 unsigned olen; 1078 1079 olen = option[IPOPT_OLEN]; 1080#ifdef DIAGNOSTIC 1081 if (ipprintfs) 1082 printf("save_rte: olen %d\n", olen); 1083#endif 1084 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1085 return; 1086 bcopy((caddr_t)option, (caddr_t)ip_srcrt.srcopt, olen); 1087 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1088 ip_srcrt.dst = dst; 1089} 1090 1091/* 1092 * Retrieve incoming source route for use in replies, 1093 * in the same form used by setsockopt. 1094 * The first hop is placed before the options, will be removed later. 1095 */ 1096struct mbuf * 1097ip_srcroute() 1098{ 1099 register struct in_addr *p, *q; 1100 register struct mbuf *m; 1101 1102 if (ip_nhops == 0) 1103 return ((struct mbuf *)0); 1104 m = m_get(M_DONTWAIT, MT_SOOPTS); 1105 if (m == 0) 1106 return ((struct mbuf *)0); 1107 1108#define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1109 1110 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1111 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1112 OPTSIZ; 1113#ifdef DIAGNOSTIC 1114 if (ipprintfs) 1115 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1116#endif 1117 1118 /* 1119 * First save first hop for return route 1120 */ 1121 p = &ip_srcrt.route[ip_nhops - 1]; 1122 *(mtod(m, struct in_addr *)) = *p--; 1123#ifdef DIAGNOSTIC 1124 if (ipprintfs) 1125 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1126#endif 1127 1128 /* 1129 * Copy option fields and padding (nop) to mbuf. 1130 */ 1131 ip_srcrt.nop = IPOPT_NOP; 1132 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1133 bcopy((caddr_t)&ip_srcrt.nop, 1134 mtod(m, caddr_t) + sizeof(struct in_addr), OPTSIZ); 1135 q = (struct in_addr *)(mtod(m, caddr_t) + 1136 sizeof(struct in_addr) + OPTSIZ); 1137#undef OPTSIZ 1138 /* 1139 * Record return path as an IP source route, 1140 * reversing the path (pointers are now aligned). 1141 */ 1142 while (p >= ip_srcrt.route) { 1143#ifdef DIAGNOSTIC 1144 if (ipprintfs) 1145 printf(" %x", ntohl(q->s_addr)); 1146#endif 1147 *q++ = *p--; 1148 } 1149 /* 1150 * Last hop goes to final destination. 1151 */ 1152 *q = ip_srcrt.dst; 1153#ifdef DIAGNOSTIC 1154 if (ipprintfs) 1155 printf(" %x\n", ntohl(q->s_addr)); 1156#endif 1157 return (m); 1158} 1159 1160/* 1161 * Strip out IP options, at higher 1162 * level protocol in the kernel. 1163 * Second argument is buffer to which options 1164 * will be moved, and return value is their length. 1165 * XXX should be deleted; last arg currently ignored. 1166 */ 1167void 1168ip_stripoptions(m, mopt) 1169 register struct mbuf *m; 1170 struct mbuf *mopt; 1171{ 1172 register int i; 1173 struct ip *ip = mtod(m, struct ip *); 1174 register caddr_t opts; 1175 int olen; 1176 1177 olen = (ip->ip_hl << 2) - sizeof (struct ip); 1178 opts = (caddr_t)(ip + 1); 1179 i = m->m_len - (sizeof (struct ip) + olen); 1180 bcopy(opts + olen, opts, (unsigned)i); 1181 m->m_len -= olen; 1182 if (m->m_flags & M_PKTHDR) 1183 m->m_pkthdr.len -= olen; 1184 ip->ip_len -= olen; 1185 ip->ip_hl = sizeof (struct ip) >> 2; 1186} 1187 1188int inetctlerrmap[PRC_NCMDS] = { 1189 0, 0, 0, 0, 1190 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1191 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1192 EMSGSIZE, EHOSTUNREACH, 0, 0, 1193 0, 0, 0, 0, 1194 ENOPROTOOPT 1195}; 1196 1197/* 1198 * Forward a packet. If some error occurs return the sender 1199 * an icmp packet. Note we can't always generate a meaningful 1200 * icmp message because icmp doesn't have a large enough repertoire 1201 * of codes and types. 1202 * 1203 * If not forwarding, just drop the packet. This could be confusing 1204 * if ipforwarding was zero but some routing protocol was advancing 1205 * us as a gateway to somewhere. However, we must let the routing 1206 * protocol deal with that. 1207 * 1208 * The srcrt parameter indicates whether the packet is being forwarded 1209 * via a source route. 1210 */ 1211void 1212ip_forward(m, srcrt) 1213 struct mbuf *m; 1214 int srcrt; 1215{ 1216 register struct ip *ip = mtod(m, struct ip *); 1217 register struct sockaddr_in *sin; 1218 register struct rtentry *rt; 1219 int error, type = 0, code = 0; 1220 struct mbuf *mcopy; 1221 n_long dest; 1222 struct ifnet *destifp; 1223 1224 dest = 0; 1225#ifdef DIAGNOSTIC 1226 if (ipprintfs) 1227 printf("forward: src %2.2x dst %2.2x ttl %x\n", 1228 ntohl(ip->ip_src.s_addr), 1229 ntohl(ip->ip_dst.s_addr), ip->ip_ttl); 1230#endif 1231 if (m->m_flags & M_BCAST || in_canforward(ip->ip_dst) == 0) { 1232 ipstat.ips_cantforward++; 1233 m_freem(m); 1234 return; 1235 } 1236 if (ip->ip_ttl <= IPTTLDEC) { 1237 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1238 return; 1239 } 1240 ip->ip_ttl -= IPTTLDEC; 1241 1242 sin = satosin(&ipforward_rt.ro_dst); 1243 if ((rt = ipforward_rt.ro_rt) == 0 || 1244 !in_hosteq(ip->ip_dst, sin->sin_addr)) { 1245 if (ipforward_rt.ro_rt) { 1246 RTFREE(ipforward_rt.ro_rt); 1247 ipforward_rt.ro_rt = 0; 1248 } 1249 sin->sin_family = AF_INET; 1250 sin->sin_len = sizeof(struct sockaddr_in); 1251 sin->sin_addr = ip->ip_dst; 1252 1253 rtalloc(&ipforward_rt); 1254 if (ipforward_rt.ro_rt == 0) { 1255 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0); 1256 return; 1257 } 1258 rt = ipforward_rt.ro_rt; 1259 } 1260 1261 /* 1262 * Save at most 68 bytes of the packet in case 1263 * we need to generate an ICMP message to the src. 1264 */ 1265 mcopy = m_copy(m, 0, imin((int)ip->ip_len, 68)); 1266 1267 /* 1268 * If forwarding packet using same interface that it came in on, 1269 * perhaps should send a redirect to sender to shortcut a hop. 1270 * Only send redirect if source is sending directly to us, 1271 * and if packet was not source routed (or has any options). 1272 * Also, don't send redirect if forwarding using a default route 1273 * or a route modified by a redirect. 1274 */ 1275 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1276 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1277 !in_nullhost(satosin(rt_key(rt))->sin_addr) && 1278 ipsendredirects && !srcrt) { 1279 if (rt->rt_ifa && 1280 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1281 ifatoia(rt->rt_ifa)->ia_subnet) { 1282 if (rt->rt_flags & RTF_GATEWAY) 1283 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1284 else 1285 dest = ip->ip_dst.s_addr; 1286 /* 1287 * Router requirements says to only send host 1288 * redirects. 1289 */ 1290 type = ICMP_REDIRECT; 1291 code = ICMP_REDIRECT_HOST; 1292#ifdef DIAGNOSTIC 1293 if (ipprintfs) 1294 printf("redirect (%d) to %x\n", code, 1295 (u_int32_t)dest); 1296#endif 1297 } 1298 } 1299 1300 error = ip_output(m, (struct mbuf *)0, &ipforward_rt, 1301 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 0); 1302 if (error) 1303 ipstat.ips_cantforward++; 1304 else { 1305 ipstat.ips_forward++; 1306 if (type) 1307 ipstat.ips_redirectsent++; 1308 else { 1309 if (mcopy) { 1310#ifdef GATEWAY 1311 if (mcopy->m_flags & M_CANFASTFWD) 1312 ipflow_create(&ipforward_rt, mcopy); 1313#endif 1314 m_freem(mcopy); 1315 } 1316 return; 1317 } 1318 } 1319 if (mcopy == NULL) 1320 return; 1321 destifp = NULL; 1322 1323 switch (error) { 1324 1325 case 0: /* forwarded, but need redirect */ 1326 /* type, code set above */ 1327 break; 1328 1329 case ENETUNREACH: /* shouldn't happen, checked above */ 1330 case EHOSTUNREACH: 1331 case ENETDOWN: 1332 case EHOSTDOWN: 1333 default: 1334 type = ICMP_UNREACH; 1335 code = ICMP_UNREACH_HOST; 1336 break; 1337 1338 case EMSGSIZE: 1339 type = ICMP_UNREACH; 1340 code = ICMP_UNREACH_NEEDFRAG; 1341 if (ipforward_rt.ro_rt) 1342 destifp = ipforward_rt.ro_rt->rt_ifp; 1343 ipstat.ips_cantfrag++; 1344 break; 1345 1346 case ENOBUFS: 1347 type = ICMP_SOURCEQUENCH; 1348 code = 0; 1349 break; 1350 } 1351 icmp_error(mcopy, type, code, dest, destifp); 1352} 1353 1354void 1355ip_savecontrol(inp, mp, ip, m) 1356 register struct inpcb *inp; 1357 register struct mbuf **mp; 1358 register struct ip *ip; 1359 register struct mbuf *m; 1360{ 1361 1362 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 1363 struct timeval tv; 1364 1365 microtime(&tv); 1366 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1367 SCM_TIMESTAMP, SOL_SOCKET); 1368 if (*mp) 1369 mp = &(*mp)->m_next; 1370 } 1371 if (inp->inp_flags & INP_RECVDSTADDR) { 1372 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst, 1373 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 1374 if (*mp) 1375 mp = &(*mp)->m_next; 1376 } 1377#ifdef notyet 1378 /* 1379 * XXX 1380 * Moving these out of udp_input() made them even more broken 1381 * than they already were. 1382 * - fenner@parc.xerox.com 1383 */ 1384 /* options were tossed already */ 1385 if (inp->inp_flags & INP_RECVOPTS) { 1386 *mp = sbcreatecontrol((caddr_t) opts_deleted_above, 1387 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 1388 if (*mp) 1389 mp = &(*mp)->m_next; 1390 } 1391 /* ip_srcroute doesn't do what we want here, need to fix */ 1392 if (inp->inp_flags & INP_RECVRETOPTS) { 1393 *mp = sbcreatecontrol((caddr_t) ip_srcroute(), 1394 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 1395 if (*mp) 1396 mp = &(*mp)->m_next; 1397 } 1398#endif 1399 if (inp->inp_flags & INP_RECVIF) { 1400 struct sockaddr_dl sdl; 1401 1402 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]); 1403 sdl.sdl_family = AF_LINK; 1404 sdl.sdl_index = m->m_pkthdr.rcvif ? 1405 m->m_pkthdr.rcvif->if_index : 0; 1406 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0; 1407 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len, 1408 IP_RECVIF, IPPROTO_IP); 1409 if (*mp) 1410 mp = &(*mp)->m_next; 1411 } 1412} 1413 1414int 1415ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 1416 int *name; 1417 u_int namelen; 1418 void *oldp; 1419 size_t *oldlenp; 1420 void *newp; 1421 size_t newlen; 1422{ 1423 extern int subnetsarelocal; 1424 1425 int error, old; 1426 1427 /* All sysctl names at this level are terminal. */ 1428 if (namelen != 1) 1429 return (ENOTDIR); 1430 1431 switch (name[0]) { 1432 case IPCTL_FORWARDING: 1433 return (sysctl_int(oldp, oldlenp, newp, newlen, &ipforwarding)); 1434 case IPCTL_SENDREDIRECTS: 1435 return (sysctl_int(oldp, oldlenp, newp, newlen, 1436 &ipsendredirects)); 1437 case IPCTL_DEFTTL: 1438 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_defttl)); 1439#ifdef notyet 1440 case IPCTL_DEFMTU: 1441 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu)); 1442#endif 1443 case IPCTL_FORWSRCRT: 1444 /* Don't allow this to change in a secure environment. */ 1445 if (securelevel > 0) 1446 return (sysctl_rdint(oldp, oldlenp, newp, 1447 ip_forwsrcrt)); 1448 else 1449 return (sysctl_int(oldp, oldlenp, newp, newlen, 1450 &ip_forwsrcrt)); 1451 case IPCTL_DIRECTEDBCAST: 1452 return (sysctl_int(oldp, oldlenp, newp, newlen, 1453 &ip_directedbcast)); 1454 case IPCTL_ALLOWSRCRT: 1455 return (sysctl_int(oldp, oldlenp, newp, newlen, 1456 &ip_allowsrcrt)); 1457 case IPCTL_SUBNETSARELOCAL: 1458 return (sysctl_int(oldp, oldlenp, newp, newlen, 1459 &subnetsarelocal)); 1460 case IPCTL_MTUDISC: 1461 error = sysctl_int(oldp, oldlenp, newp, newlen, 1462 &ip_mtudisc); 1463 if (ip_mtudisc != 0 && ip_mtudisc_timeout_q == NULL) { 1464 ip_mtudisc_timeout_q = 1465 rt_timer_queue_create(ip_mtudisc_timeout); 1466 } else if (ip_mtudisc == 0 && ip_mtudisc_timeout_q != NULL) { 1467 rt_timer_queue_destroy(ip_mtudisc_timeout_q, TRUE); 1468 ip_mtudisc_timeout_q = NULL; 1469 } 1470 return error; 1471 case IPCTL_ANONPORTMIN: 1472 old = anonportmin; 1473 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmin); 1474 if (anonportmin >= anonportmax || anonportmin > 65535 1475#ifndef IPNOPRIVPORTS 1476 || anonportmin < IPPORT_RESERVED 1477#endif 1478 ) { 1479 anonportmin = old; 1480 return (EINVAL); 1481 } 1482 return (error); 1483 case IPCTL_ANONPORTMAX: 1484 old = anonportmax; 1485 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmax); 1486 if (anonportmin >= anonportmax || anonportmax > 65535 1487#ifndef IPNOPRIVPORTS 1488 || anonportmax < IPPORT_RESERVED 1489#endif 1490 ) { 1491 anonportmax = old; 1492 return (EINVAL); 1493 } 1494 return (error); 1495 case IPCTL_MTUDISCTIMEOUT: 1496 error = sysctl_int(oldp, oldlenp, newp, newlen, 1497 &ip_mtudisc_timeout); 1498 if (ip_mtudisc_timeout_q != NULL) 1499 rt_timer_queue_change(ip_mtudisc_timeout_q, 1500 ip_mtudisc_timeout); 1501 return (error); 1502#ifdef GATEWAY 1503 case IPCTL_MAXFLOWS: 1504 { 1505 int s; 1506 1507 error = sysctl_int(oldp, oldlenp, newp, newlen, 1508 &ip_maxflows); 1509 s = splsoftnet(); 1510 ipflow_reap(0); 1511 splx(s); 1512 return (error); 1513 } 1514#endif 1515 default: 1516 return (EOPNOTSUPP); 1517 } 1518 /* NOTREACHED */ 1519} 1520