ip_input.c revision 1.63
1/* $NetBSD: ip_input.c,v 1.63 1998/04/29 21:37:55 matt 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_mrouting.h" 77 78#include <sys/param.h> 79#include <sys/systm.h> 80#include <sys/malloc.h> 81#include <sys/mbuf.h> 82#include <sys/domain.h> 83#include <sys/protosw.h> 84#include <sys/socket.h> 85#include <sys/socketvar.h> 86#include <sys/errno.h> 87#include <sys/time.h> 88#include <sys/kernel.h> 89#include <sys/proc.h> 90 91#include <vm/vm.h> 92#include <sys/sysctl.h> 93 94#include <net/if.h> 95#include <net/if_dl.h> 96#include <net/route.h> 97#include <net/pfil.h> 98 99#include <netinet/in.h> 100#include <netinet/in_systm.h> 101#include <netinet/ip.h> 102#include <netinet/in_pcb.h> 103#include <netinet/in_var.h> 104#include <netinet/ip_var.h> 105#include <netinet/ip_icmp.h> 106 107#ifndef IPFORWARDING 108#ifdef GATEWAY 109#define IPFORWARDING 1 /* forward IP packets not for us */ 110#else /* GATEWAY */ 111#define IPFORWARDING 0 /* don't forward IP packets not for us */ 112#endif /* GATEWAY */ 113#endif /* IPFORWARDING */ 114#ifndef IPSENDREDIRECTS 115#define IPSENDREDIRECTS 1 116#endif 117#ifndef IPFORWSRCRT 118#define IPFORWSRCRT 1 /* forward source-routed packets */ 119#endif 120#ifndef IPALLOWSRCRT 121#define IPALLOWSRCRT 1 /* allow source-routed packets */ 122#endif 123#ifndef IPMTUDISC 124#define IPMTUDISC 0 125#endif 126#ifndef IPMTUDISCTIMEOUT 127#define IPMTUDISCTIMEOUT (10 * 60) /* as per RFC 1191 */ 128#endif 129 130/* 131 * Note: DIRECTED_BROADCAST is handled this way so that previous 132 * configuration using this option will Just Work. 133 */ 134#ifndef IPDIRECTEDBCAST 135#ifdef DIRECTED_BROADCAST 136#define IPDIRECTEDBCAST 1 137#else 138#define IPDIRECTEDBCAST 0 139#endif /* DIRECTED_BROADCAST */ 140#endif /* IPDIRECTEDBCAST */ 141int ipforwarding = IPFORWARDING; 142int ipsendredirects = IPSENDREDIRECTS; 143int ip_defttl = IPDEFTTL; 144int ip_forwsrcrt = IPFORWSRCRT; 145int ip_directedbcast = IPDIRECTEDBCAST; 146int ip_allowsrcrt = IPALLOWSRCRT; 147int ip_mtudisc = IPMTUDISC; 148u_int ip_mtudisc_timeout = IPMTUDISCTIMEOUT; 149#ifdef DIAGNOSTIC 150int ipprintfs = 0; 151#endif 152 153struct rttimer_queue *ip_mtudisc_timeout_q = NULL; 154 155extern struct domain inetdomain; 156extern struct protosw inetsw[]; 157u_char ip_protox[IPPROTO_MAX]; 158int ipqmaxlen = IFQ_MAXLEN; 159struct in_ifaddrhead in_ifaddr; 160struct in_ifaddrhashhead *in_ifaddrhashtbl; 161struct ifqueue ipintrq; 162struct ipstat ipstat; 163u_int16_t ip_id; 164int ip_defttl; 165struct ipqhead ipq; 166 167/* 168 * We need to save the IP options in case a protocol wants to respond 169 * to an incoming packet over the same route if the packet got here 170 * using IP source routing. This allows connection establishment and 171 * maintenance when the remote end is on a network that is not known 172 * to us. 173 */ 174int ip_nhops = 0; 175static struct ip_srcrt { 176 struct in_addr dst; /* final destination */ 177 char nop; /* one NOP to align */ 178 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */ 179 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)]; 180} ip_srcrt; 181 182static void save_rte __P((u_char *, struct in_addr)); 183 184/* 185 * IP initialization: fill in IP protocol switch table. 186 * All protocols not implemented in kernel go to raw IP protocol handler. 187 */ 188void 189ip_init() 190{ 191 register struct protosw *pr; 192 register int i; 193 194 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); 195 if (pr == 0) 196 panic("ip_init"); 197 for (i = 0; i < IPPROTO_MAX; i++) 198 ip_protox[i] = pr - inetsw; 199 for (pr = inetdomain.dom_protosw; 200 pr < inetdomain.dom_protoswNPROTOSW; pr++) 201 if (pr->pr_domain->dom_family == PF_INET && 202 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 203 ip_protox[pr->pr_protocol] = pr - inetsw; 204 LIST_INIT(&ipq); 205 ip_id = time.tv_sec & 0xffff; 206 ipintrq.ifq_maxlen = ipqmaxlen; 207 TAILQ_INIT(&in_ifaddr); 208 in_ifaddrhashtbl = 209 hashinit(IN_IFADDR_HASH_SIZE, M_IFADDR, M_WAITOK, &in_ifaddrhash); 210 if (ip_mtudisc != 0) 211 ip_mtudisc_timeout_q = 212 rt_timer_queue_create(ip_mtudisc_timeout); 213} 214 215struct sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET }; 216struct route ipforward_rt; 217 218/* 219 * Ip input routine. Checksum and byte swap header. If fragmented 220 * try to reassemble. Process options. Pass to next level. 221 */ 222void 223ipintr() 224{ 225 register struct ip *ip = NULL; 226 register struct mbuf *m; 227 register struct ipq *fp; 228 register struct in_ifaddr *ia; 229 register struct ifaddr *ifa; 230 struct ipqent *ipqe; 231 int hlen = 0, mff, len, s; 232#ifdef PFIL_HOOKS 233 struct packet_filter_hook *pfh; 234 struct mbuf *m0; 235 int rv; 236#endif /* PFIL_HOOKS */ 237 238next: 239 /* 240 * Get next datagram off input queue and get IP header 241 * in first mbuf. 242 */ 243 s = splimp(); 244 IF_DEQUEUE(&ipintrq, m); 245 splx(s); 246 if (m == 0) 247 return; 248#ifdef DIAGNOSTIC 249 if ((m->m_flags & M_PKTHDR) == 0) 250 panic("ipintr no HDR"); 251#endif 252 /* 253 * If no IP addresses have been set yet but the interfaces 254 * are receiving, can't do anything with incoming packets yet. 255 */ 256 if (in_ifaddr.tqh_first == 0) 257 goto bad; 258 ipstat.ips_total++; 259 if (m->m_len < sizeof (struct ip) && 260 (m = m_pullup(m, sizeof (struct ip))) == 0) { 261 ipstat.ips_toosmall++; 262 goto next; 263 } 264 ip = mtod(m, struct ip *); 265 if (ip->ip_v != IPVERSION) { 266 ipstat.ips_badvers++; 267 goto bad; 268 } 269 hlen = ip->ip_hl << 2; 270 if (hlen < sizeof(struct ip)) { /* minimum header length */ 271 ipstat.ips_badhlen++; 272 goto bad; 273 } 274 if (hlen > m->m_len) { 275 if ((m = m_pullup(m, hlen)) == 0) { 276 ipstat.ips_badhlen++; 277 goto next; 278 } 279 ip = mtod(m, struct ip *); 280 } 281 if ((ip->ip_sum = in_cksum(m, hlen)) != 0) { 282 ipstat.ips_badsum++; 283 goto bad; 284 } 285 286 /* 287 * Convert fields to host representation. 288 */ 289 NTOHS(ip->ip_len); 290 NTOHS(ip->ip_id); 291 NTOHS(ip->ip_off); 292 len = ip->ip_len; 293 294 /* 295 * Check that the amount of data in the buffers 296 * is as at least much as the IP header would have us expect. 297 * Trim mbufs if longer than we expect. 298 * Drop packet if shorter than we expect. 299 */ 300 if (m->m_pkthdr.len < len) { 301 ipstat.ips_tooshort++; 302 goto bad; 303 } 304 if (m->m_pkthdr.len > len) { 305 if (m->m_len == m->m_pkthdr.len) { 306 m->m_len = len; 307 m->m_pkthdr.len = len; 308 } else 309 m_adj(m, len - m->m_pkthdr.len); 310 } 311 312#ifdef PFIL_HOOKS 313 /* 314 * Run through list of hooks for input packets. 315 */ 316 m0 = m; 317 for (pfh = pfil_hook_get(PFIL_IN); pfh; pfh = pfh->pfil_link.tqe_next) 318 if (pfh->pfil_func) { 319 rv = pfh->pfil_func(ip, hlen, m->m_pkthdr.rcvif, 0, &m0); 320 if (rv) 321 goto next; 322 ip = mtod(m = m0, struct ip *); 323 } 324#endif /* PFIL_HOOKS */ 325 326 /* 327 * Process options and, if not destined for us, 328 * ship it on. ip_dooptions returns 1 when an 329 * error was detected (causing an icmp message 330 * to be sent and the original packet to be freed). 331 */ 332 ip_nhops = 0; /* for source routed packets */ 333 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 334 goto next; 335 336 /* 337 * Check our list of addresses, to see if the packet is for us. 338 */ 339 INADDR_TO_IA(ip->ip_dst, ia); 340 if (ia != NULL) goto ours; 341 if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 342 for (ifa = m->m_pkthdr.rcvif->if_addrlist.tqh_first; 343 ifa != NULL; ifa = ifa->ifa_list.tqe_next) { 344 if (ifa->ifa_addr->sa_family != AF_INET) continue; 345 ia = ifatoia(ifa); 346 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 347 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 348 /* 349 * Look for all-0's host part (old broadcast addr), 350 * either for subnet or net. 351 */ 352 ip->ip_dst.s_addr == ia->ia_subnet || 353 ip->ip_dst.s_addr == ia->ia_net) 354 goto ours; 355 /* 356 * An interface with IP address zero accepts 357 * all packets that arrive on that interface. 358 */ 359 if (in_nullhost(ia->ia_addr.sin_addr)) 360 goto ours; 361 } 362 } 363 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 364 struct in_multi *inm; 365#ifdef MROUTING 366 extern struct socket *ip_mrouter; 367 368 if (m->m_flags & M_EXT) { 369 if ((m = m_pullup(m, hlen)) == 0) { 370 ipstat.ips_toosmall++; 371 goto next; 372 } 373 ip = mtod(m, struct ip *); 374 } 375 376 if (ip_mrouter) { 377 /* 378 * If we are acting as a multicast router, all 379 * incoming multicast packets are passed to the 380 * kernel-level multicast forwarding function. 381 * The packet is returned (relatively) intact; if 382 * ip_mforward() returns a non-zero value, the packet 383 * must be discarded, else it may be accepted below. 384 * 385 * (The IP ident field is put in the same byte order 386 * as expected when ip_mforward() is called from 387 * ip_output().) 388 */ 389 ip->ip_id = htons(ip->ip_id); 390 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 391 ipstat.ips_cantforward++; 392 m_freem(m); 393 goto next; 394 } 395 ip->ip_id = ntohs(ip->ip_id); 396 397 /* 398 * The process-level routing demon needs to receive 399 * all multicast IGMP packets, whether or not this 400 * host belongs to their destination groups. 401 */ 402 if (ip->ip_p == IPPROTO_IGMP) 403 goto ours; 404 ipstat.ips_forward++; 405 } 406#endif 407 /* 408 * See if we belong to the destination multicast group on the 409 * arrival interface. 410 */ 411 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 412 if (inm == NULL) { 413 ipstat.ips_cantforward++; 414 m_freem(m); 415 goto next; 416 } 417 goto ours; 418 } 419 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 420 in_nullhost(ip->ip_dst)) 421 goto ours; 422 423 /* 424 * Not for us; forward if possible and desirable. 425 */ 426 if (ipforwarding == 0) { 427 ipstat.ips_cantforward++; 428 m_freem(m); 429 } else 430 ip_forward(m, 0); 431 goto next; 432 433ours: 434 /* 435 * If offset or IP_MF are set, must reassemble. 436 * Otherwise, nothing need be done. 437 * (We could look in the reassembly queue to see 438 * if the packet was previously fragmented, 439 * but it's not worth the time; just let them time out.) 440 */ 441 if (ip->ip_off & ~(IP_DF|IP_RF)) { 442 /* 443 * Look for queue of fragments 444 * of this datagram. 445 */ 446 for (fp = ipq.lh_first; fp != NULL; fp = fp->ipq_q.le_next) 447 if (ip->ip_id == fp->ipq_id && 448 in_hosteq(ip->ip_src, fp->ipq_src) && 449 in_hosteq(ip->ip_dst, fp->ipq_dst) && 450 ip->ip_p == fp->ipq_p) 451 goto found; 452 fp = 0; 453found: 454 455 /* 456 * Adjust ip_len to not reflect header, 457 * set ipqe_mff if more fragments are expected, 458 * convert offset of this to bytes. 459 */ 460 ip->ip_len -= hlen; 461 mff = (ip->ip_off & IP_MF) != 0; 462 if (mff) { 463 /* 464 * Make sure that fragments have a data length 465 * that's a non-zero multiple of 8 bytes. 466 */ 467 if (ip->ip_len == 0 || (ip->ip_len & 0x7) != 0) { 468 ipstat.ips_badfrags++; 469 goto bad; 470 } 471 } 472 ip->ip_off <<= 3; 473 474 /* 475 * If datagram marked as having more fragments 476 * or if this is not the first fragment, 477 * attempt reassembly; if it succeeds, proceed. 478 */ 479 if (mff || ip->ip_off) { 480 ipstat.ips_fragments++; 481 MALLOC(ipqe, struct ipqent *, sizeof (struct ipqent), 482 M_IPQ, M_NOWAIT); 483 if (ipqe == NULL) { 484 ipstat.ips_rcvmemdrop++; 485 goto bad; 486 } 487 ipqe->ipqe_mff = mff; 488 ipqe->ipqe_m = m; 489 ipqe->ipqe_ip = ip; 490 m = ip_reass(ipqe, fp); 491 if (m == 0) 492 goto next; 493 ipstat.ips_reassembled++; 494 ip = mtod(m, struct ip *); 495 } else 496 if (fp) 497 ip_freef(fp); 498 } else 499 ip->ip_len -= hlen; 500 501 /* 502 * Switch out to protocol's input routine. 503 */ 504 ipstat.ips_delivered++; 505 (*inetsw[ip_protox[ip->ip_p]].pr_input)(m, hlen); 506 goto next; 507bad: 508 m_freem(m); 509 goto next; 510} 511 512/* 513 * Take incoming datagram fragment and try to 514 * reassemble it into whole datagram. If a chain for 515 * reassembly of this datagram already exists, then it 516 * is given as fp; otherwise have to make a chain. 517 */ 518struct mbuf * 519ip_reass(ipqe, fp) 520 register struct ipqent *ipqe; 521 register struct ipq *fp; 522{ 523 register struct mbuf *m = ipqe->ipqe_m; 524 register struct ipqent *nq, *p, *q; 525 struct ip *ip; 526 struct mbuf *t; 527 int hlen = ipqe->ipqe_ip->ip_hl << 2; 528 int i, next; 529 530 /* 531 * Presence of header sizes in mbufs 532 * would confuse code below. 533 */ 534 m->m_data += hlen; 535 m->m_len -= hlen; 536 537 /* 538 * If first fragment to arrive, create a reassembly queue. 539 */ 540 if (fp == 0) { 541 MALLOC(fp, struct ipq *, sizeof (struct ipq), 542 M_FTABLE, M_NOWAIT); 543 if (fp == NULL) 544 goto dropfrag; 545 LIST_INSERT_HEAD(&ipq, fp, ipq_q); 546 fp->ipq_ttl = IPFRAGTTL; 547 fp->ipq_p = ipqe->ipqe_ip->ip_p; 548 fp->ipq_id = ipqe->ipqe_ip->ip_id; 549 LIST_INIT(&fp->ipq_fragq); 550 fp->ipq_src = ipqe->ipqe_ip->ip_src; 551 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 552 p = NULL; 553 goto insert; 554 } 555 556 /* 557 * Find a segment which begins after this one does. 558 */ 559 for (p = NULL, q = fp->ipq_fragq.lh_first; q != NULL; 560 p = q, q = q->ipqe_q.le_next) 561 if (q->ipqe_ip->ip_off > ipqe->ipqe_ip->ip_off) 562 break; 563 564 /* 565 * If there is a preceding segment, it may provide some of 566 * our data already. If so, drop the data from the incoming 567 * segment. If it provides all of our data, drop us. 568 */ 569 if (p != NULL) { 570 i = p->ipqe_ip->ip_off + p->ipqe_ip->ip_len - 571 ipqe->ipqe_ip->ip_off; 572 if (i > 0) { 573 if (i >= ipqe->ipqe_ip->ip_len) 574 goto dropfrag; 575 m_adj(ipqe->ipqe_m, i); 576 ipqe->ipqe_ip->ip_off += i; 577 ipqe->ipqe_ip->ip_len -= i; 578 } 579 } 580 581 /* 582 * While we overlap succeeding segments trim them or, 583 * if they are completely covered, dequeue them. 584 */ 585 for (; q != NULL && ipqe->ipqe_ip->ip_off + ipqe->ipqe_ip->ip_len > 586 q->ipqe_ip->ip_off; q = nq) { 587 i = (ipqe->ipqe_ip->ip_off + ipqe->ipqe_ip->ip_len) - 588 q->ipqe_ip->ip_off; 589 if (i < q->ipqe_ip->ip_len) { 590 q->ipqe_ip->ip_len -= i; 591 q->ipqe_ip->ip_off += i; 592 m_adj(q->ipqe_m, i); 593 break; 594 } 595 nq = q->ipqe_q.le_next; 596 m_freem(q->ipqe_m); 597 LIST_REMOVE(q, ipqe_q); 598 FREE(q, M_IPQ); 599 } 600 601insert: 602 /* 603 * Stick new segment in its place; 604 * check for complete reassembly. 605 */ 606 if (p == NULL) { 607 LIST_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 608 } else { 609 LIST_INSERT_AFTER(p, ipqe, ipqe_q); 610 } 611 next = 0; 612 for (p = NULL, q = fp->ipq_fragq.lh_first; q != NULL; 613 p = q, q = q->ipqe_q.le_next) { 614 if (q->ipqe_ip->ip_off != next) 615 return (0); 616 next += q->ipqe_ip->ip_len; 617 } 618 if (p->ipqe_mff) 619 return (0); 620 621 /* 622 * Reassembly is complete. Check for a bogus message size and 623 * concatenate fragments. 624 */ 625 q = fp->ipq_fragq.lh_first; 626 ip = q->ipqe_ip; 627 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 628 ipstat.ips_toolong++; 629 ip_freef(fp); 630 return (0); 631 } 632 m = q->ipqe_m; 633 t = m->m_next; 634 m->m_next = 0; 635 m_cat(m, t); 636 nq = q->ipqe_q.le_next; 637 FREE(q, M_IPQ); 638 for (q = nq; q != NULL; q = nq) { 639 t = q->ipqe_m; 640 nq = q->ipqe_q.le_next; 641 FREE(q, M_IPQ); 642 m_cat(m, t); 643 } 644 645 /* 646 * Create header for new ip packet by 647 * modifying header of first packet; 648 * dequeue and discard fragment reassembly header. 649 * Make header visible. 650 */ 651 ip->ip_len = next; 652 ip->ip_src = fp->ipq_src; 653 ip->ip_dst = fp->ipq_dst; 654 LIST_REMOVE(fp, ipq_q); 655 FREE(fp, M_FTABLE); 656 m->m_len += (ip->ip_hl << 2); 657 m->m_data -= (ip->ip_hl << 2); 658 /* some debugging cruft by sklower, below, will go away soon */ 659 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 660 register int plen = 0; 661 for (t = m; t; t = t->m_next) 662 plen += t->m_len; 663 m->m_pkthdr.len = plen; 664 } 665 return (m); 666 667dropfrag: 668 ipstat.ips_fragdropped++; 669 m_freem(m); 670 FREE(ipqe, M_IPQ); 671 return (0); 672} 673 674/* 675 * Free a fragment reassembly header and all 676 * associated datagrams. 677 */ 678void 679ip_freef(fp) 680 struct ipq *fp; 681{ 682 register struct ipqent *q, *p; 683 684 for (q = fp->ipq_fragq.lh_first; q != NULL; q = p) { 685 p = q->ipqe_q.le_next; 686 m_freem(q->ipqe_m); 687 LIST_REMOVE(q, ipqe_q); 688 FREE(q, M_IPQ); 689 } 690 LIST_REMOVE(fp, ipq_q); 691 FREE(fp, M_FTABLE); 692} 693 694/* 695 * IP timer processing; 696 * if a timer expires on a reassembly 697 * queue, discard it. 698 */ 699void 700ip_slowtimo() 701{ 702 register struct ipq *fp, *nfp; 703 int s = splsoftnet(); 704 705 for (fp = ipq.lh_first; fp != NULL; fp = nfp) { 706 nfp = fp->ipq_q.le_next; 707 if (--fp->ipq_ttl == 0) { 708 ipstat.ips_fragtimeout++; 709 ip_freef(fp); 710 } 711 } 712#ifdef GATEWAY 713 ipflow_slowtimo(); 714#endif 715 splx(s); 716} 717 718/* 719 * Drain off all datagram fragments. 720 */ 721void 722ip_drain() 723{ 724 725 while (ipq.lh_first != NULL) { 726 ipstat.ips_fragdropped++; 727 ip_freef(ipq.lh_first); 728 } 729} 730 731/* 732 * Do option processing on a datagram, 733 * possibly discarding it if bad options are encountered, 734 * or forwarding it if source-routed. 735 * Returns 1 if packet has been forwarded/freed, 736 * 0 if the packet should be processed further. 737 */ 738int 739ip_dooptions(m) 740 struct mbuf *m; 741{ 742 register struct ip *ip = mtod(m, struct ip *); 743 register u_char *cp; 744 register struct ip_timestamp *ipt; 745 register struct in_ifaddr *ia; 746 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 747 struct in_addr *sin, dst; 748 n_time ntime; 749 750 dst = ip->ip_dst; 751 cp = (u_char *)(ip + 1); 752 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 753 for (; cnt > 0; cnt -= optlen, cp += optlen) { 754 opt = cp[IPOPT_OPTVAL]; 755 if (opt == IPOPT_EOL) 756 break; 757 if (opt == IPOPT_NOP) 758 optlen = 1; 759 else { 760 optlen = cp[IPOPT_OLEN]; 761 if (optlen <= 0 || optlen > cnt) { 762 code = &cp[IPOPT_OLEN] - (u_char *)ip; 763 goto bad; 764 } 765 } 766 switch (opt) { 767 768 default: 769 break; 770 771 /* 772 * Source routing with record. 773 * Find interface with current destination address. 774 * If none on this machine then drop if strictly routed, 775 * or do nothing if loosely routed. 776 * Record interface address and bring up next address 777 * component. If strictly routed make sure next 778 * address is on directly accessible net. 779 */ 780 case IPOPT_LSRR: 781 case IPOPT_SSRR: 782 if (ip_allowsrcrt == 0) { 783 type = ICMP_UNREACH; 784 code = ICMP_UNREACH_NET_PROHIB; 785 goto bad; 786 } 787 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 788 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 789 goto bad; 790 } 791 ipaddr.sin_addr = ip->ip_dst; 792 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 793 if (ia == 0) { 794 if (opt == IPOPT_SSRR) { 795 type = ICMP_UNREACH; 796 code = ICMP_UNREACH_SRCFAIL; 797 goto bad; 798 } 799 /* 800 * Loose routing, and not at next destination 801 * yet; nothing to do except forward. 802 */ 803 break; 804 } 805 off--; /* 0 origin */ 806 if (off > optlen - sizeof(struct in_addr)) { 807 /* 808 * End of source route. Should be for us. 809 */ 810 save_rte(cp, ip->ip_src); 811 break; 812 } 813 /* 814 * locate outgoing interface 815 */ 816 bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr, 817 sizeof(ipaddr.sin_addr)); 818 if (opt == IPOPT_SSRR) { 819#define INA struct in_ifaddr * 820#define SA struct sockaddr * 821 ia = (INA)ifa_ifwithladdr((SA)&ipaddr); 822 } else 823 ia = ip_rtaddr(ipaddr.sin_addr); 824 if (ia == 0) { 825 type = ICMP_UNREACH; 826 code = ICMP_UNREACH_SRCFAIL; 827 goto bad; 828 } 829 ip->ip_dst = ipaddr.sin_addr; 830 bcopy((caddr_t)&ia->ia_addr.sin_addr, 831 (caddr_t)(cp + off), sizeof(struct in_addr)); 832 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 833 /* 834 * Let ip_intr's mcast routing check handle mcast pkts 835 */ 836 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 837 break; 838 839 case IPOPT_RR: 840 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 841 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 842 goto bad; 843 } 844 /* 845 * If no space remains, ignore. 846 */ 847 off--; /* 0 origin */ 848 if (off > optlen - sizeof(struct in_addr)) 849 break; 850 bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr, 851 sizeof(ipaddr.sin_addr)); 852 /* 853 * locate outgoing interface; if we're the destination, 854 * use the incoming interface (should be same). 855 */ 856 if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0 && 857 (ia = ip_rtaddr(ipaddr.sin_addr)) == 0) { 858 type = ICMP_UNREACH; 859 code = ICMP_UNREACH_HOST; 860 goto bad; 861 } 862 bcopy((caddr_t)&ia->ia_addr.sin_addr, 863 (caddr_t)(cp + off), sizeof(struct in_addr)); 864 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 865 break; 866 867 case IPOPT_TS: 868 code = cp - (u_char *)ip; 869 ipt = (struct ip_timestamp *)cp; 870 if (ipt->ipt_len < 5) 871 goto bad; 872 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 873 if (++ipt->ipt_oflw == 0) 874 goto bad; 875 break; 876 } 877 sin = (struct in_addr *)(cp + ipt->ipt_ptr - 1); 878 switch (ipt->ipt_flg) { 879 880 case IPOPT_TS_TSONLY: 881 break; 882 883 case IPOPT_TS_TSANDADDR: 884 if (ipt->ipt_ptr + sizeof(n_time) + 885 sizeof(struct in_addr) > ipt->ipt_len) 886 goto bad; 887 ipaddr.sin_addr = dst; 888 ia = (INA)ifaof_ifpforaddr((SA)&ipaddr, 889 m->m_pkthdr.rcvif); 890 if (ia == 0) 891 continue; 892 bcopy((caddr_t)&ia->ia_addr.sin_addr, 893 (caddr_t)sin, sizeof(struct in_addr)); 894 ipt->ipt_ptr += sizeof(struct in_addr); 895 break; 896 897 case IPOPT_TS_PRESPEC: 898 if (ipt->ipt_ptr + sizeof(n_time) + 899 sizeof(struct in_addr) > ipt->ipt_len) 900 goto bad; 901 bcopy((caddr_t)sin, (caddr_t)&ipaddr.sin_addr, 902 sizeof(struct in_addr)); 903 if (ifa_ifwithaddr((SA)&ipaddr) == 0) 904 continue; 905 ipt->ipt_ptr += sizeof(struct in_addr); 906 break; 907 908 default: 909 goto bad; 910 } 911 ntime = iptime(); 912 bcopy((caddr_t)&ntime, (caddr_t)cp + ipt->ipt_ptr - 1, 913 sizeof(n_time)); 914 ipt->ipt_ptr += sizeof(n_time); 915 } 916 } 917 if (forward) { 918 if (ip_forwsrcrt == 0) { 919 type = ICMP_UNREACH; 920 code = ICMP_UNREACH_SRCFAIL; 921 goto bad; 922 } 923 ip_forward(m, 1); 924 return (1); 925 } 926 return (0); 927bad: 928 ip->ip_len -= ip->ip_hl << 2; /* XXX icmp_error adds in hdr length */ 929 icmp_error(m, type, code, 0, 0); 930 ipstat.ips_badoptions++; 931 return (1); 932} 933 934/* 935 * Given address of next destination (final or next hop), 936 * return internet address info of interface to be used to get there. 937 */ 938struct in_ifaddr * 939ip_rtaddr(dst) 940 struct in_addr dst; 941{ 942 register struct sockaddr_in *sin; 943 944 sin = satosin(&ipforward_rt.ro_dst); 945 946 if (ipforward_rt.ro_rt == 0 || !in_hosteq(dst, sin->sin_addr)) { 947 if (ipforward_rt.ro_rt) { 948 RTFREE(ipforward_rt.ro_rt); 949 ipforward_rt.ro_rt = 0; 950 } 951 sin->sin_family = AF_INET; 952 sin->sin_len = sizeof(*sin); 953 sin->sin_addr = dst; 954 955 rtalloc(&ipforward_rt); 956 } 957 if (ipforward_rt.ro_rt == 0) 958 return ((struct in_ifaddr *)0); 959 return (ifatoia(ipforward_rt.ro_rt->rt_ifa)); 960} 961 962/* 963 * Save incoming source route for use in replies, 964 * to be picked up later by ip_srcroute if the receiver is interested. 965 */ 966void 967save_rte(option, dst) 968 u_char *option; 969 struct in_addr dst; 970{ 971 unsigned olen; 972 973 olen = option[IPOPT_OLEN]; 974#ifdef DIAGNOSTIC 975 if (ipprintfs) 976 printf("save_rte: olen %d\n", olen); 977#endif 978 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 979 return; 980 bcopy((caddr_t)option, (caddr_t)ip_srcrt.srcopt, olen); 981 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 982 ip_srcrt.dst = dst; 983} 984 985/* 986 * Retrieve incoming source route for use in replies, 987 * in the same form used by setsockopt. 988 * The first hop is placed before the options, will be removed later. 989 */ 990struct mbuf * 991ip_srcroute() 992{ 993 register struct in_addr *p, *q; 994 register struct mbuf *m; 995 996 if (ip_nhops == 0) 997 return ((struct mbuf *)0); 998 m = m_get(M_DONTWAIT, MT_SOOPTS); 999 if (m == 0) 1000 return ((struct mbuf *)0); 1001 1002#define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1003 1004 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1005 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1006 OPTSIZ; 1007#ifdef DIAGNOSTIC 1008 if (ipprintfs) 1009 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1010#endif 1011 1012 /* 1013 * First save first hop for return route 1014 */ 1015 p = &ip_srcrt.route[ip_nhops - 1]; 1016 *(mtod(m, struct in_addr *)) = *p--; 1017#ifdef DIAGNOSTIC 1018 if (ipprintfs) 1019 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1020#endif 1021 1022 /* 1023 * Copy option fields and padding (nop) to mbuf. 1024 */ 1025 ip_srcrt.nop = IPOPT_NOP; 1026 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1027 bcopy((caddr_t)&ip_srcrt.nop, 1028 mtod(m, caddr_t) + sizeof(struct in_addr), OPTSIZ); 1029 q = (struct in_addr *)(mtod(m, caddr_t) + 1030 sizeof(struct in_addr) + OPTSIZ); 1031#undef OPTSIZ 1032 /* 1033 * Record return path as an IP source route, 1034 * reversing the path (pointers are now aligned). 1035 */ 1036 while (p >= ip_srcrt.route) { 1037#ifdef DIAGNOSTIC 1038 if (ipprintfs) 1039 printf(" %x", ntohl(q->s_addr)); 1040#endif 1041 *q++ = *p--; 1042 } 1043 /* 1044 * Last hop goes to final destination. 1045 */ 1046 *q = ip_srcrt.dst; 1047#ifdef DIAGNOSTIC 1048 if (ipprintfs) 1049 printf(" %x\n", ntohl(q->s_addr)); 1050#endif 1051 return (m); 1052} 1053 1054/* 1055 * Strip out IP options, at higher 1056 * level protocol in the kernel. 1057 * Second argument is buffer to which options 1058 * will be moved, and return value is their length. 1059 * XXX should be deleted; last arg currently ignored. 1060 */ 1061void 1062ip_stripoptions(m, mopt) 1063 register struct mbuf *m; 1064 struct mbuf *mopt; 1065{ 1066 register int i; 1067 struct ip *ip = mtod(m, struct ip *); 1068 register caddr_t opts; 1069 int olen; 1070 1071 olen = (ip->ip_hl<<2) - sizeof (struct ip); 1072 opts = (caddr_t)(ip + 1); 1073 i = m->m_len - (sizeof (struct ip) + olen); 1074 bcopy(opts + olen, opts, (unsigned)i); 1075 m->m_len -= olen; 1076 if (m->m_flags & M_PKTHDR) 1077 m->m_pkthdr.len -= olen; 1078 ip->ip_hl = sizeof(struct ip) >> 2; 1079} 1080 1081int inetctlerrmap[PRC_NCMDS] = { 1082 0, 0, 0, 0, 1083 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1084 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1085 EMSGSIZE, EHOSTUNREACH, 0, 0, 1086 0, 0, 0, 0, 1087 ENOPROTOOPT 1088}; 1089 1090/* 1091 * Forward a packet. If some error occurs return the sender 1092 * an icmp packet. Note we can't always generate a meaningful 1093 * icmp message because icmp doesn't have a large enough repertoire 1094 * of codes and types. 1095 * 1096 * If not forwarding, just drop the packet. This could be confusing 1097 * if ipforwarding was zero but some routing protocol was advancing 1098 * us as a gateway to somewhere. However, we must let the routing 1099 * protocol deal with that. 1100 * 1101 * The srcrt parameter indicates whether the packet is being forwarded 1102 * via a source route. 1103 */ 1104void 1105ip_forward(m, srcrt) 1106 struct mbuf *m; 1107 int srcrt; 1108{ 1109 register struct ip *ip = mtod(m, struct ip *); 1110 register struct sockaddr_in *sin; 1111 register struct rtentry *rt; 1112 int error, type = 0, code = 0; 1113 struct mbuf *mcopy; 1114 n_long dest; 1115 struct ifnet *destifp; 1116 1117 dest = 0; 1118#ifdef DIAGNOSTIC 1119 if (ipprintfs) 1120 printf("forward: src %x dst %x ttl %x\n", 1121 ip->ip_src.s_addr, ip->ip_dst.s_addr, ip->ip_ttl); 1122#endif 1123 if (m->m_flags & M_BCAST || in_canforward(ip->ip_dst) == 0) { 1124 ipstat.ips_cantforward++; 1125 m_freem(m); 1126 return; 1127 } 1128 HTONS(ip->ip_id); 1129 if (ip->ip_ttl <= IPTTLDEC) { 1130 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1131 return; 1132 } 1133 ip->ip_ttl -= IPTTLDEC; 1134 1135 sin = satosin(&ipforward_rt.ro_dst); 1136 if ((rt = ipforward_rt.ro_rt) == 0 || 1137 !in_hosteq(ip->ip_dst, sin->sin_addr)) { 1138 if (ipforward_rt.ro_rt) { 1139 RTFREE(ipforward_rt.ro_rt); 1140 ipforward_rt.ro_rt = 0; 1141 } 1142 sin->sin_family = AF_INET; 1143 sin->sin_len = sizeof(struct sockaddr_in); 1144 sin->sin_addr = ip->ip_dst; 1145 1146 rtalloc(&ipforward_rt); 1147 if (ipforward_rt.ro_rt == 0) { 1148 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0); 1149 return; 1150 } 1151 rt = ipforward_rt.ro_rt; 1152 } 1153 1154 /* 1155 * Save at most 68 bytes of the packet in case 1156 * we need to generate an ICMP message to the src. 1157 */ 1158 mcopy = m_copy(m, 0, imin((int)ip->ip_len, 68)); 1159 1160 /* 1161 * If forwarding packet using same interface that it came in on, 1162 * perhaps should send a redirect to sender to shortcut a hop. 1163 * Only send redirect if source is sending directly to us, 1164 * and if packet was not source routed (or has any options). 1165 * Also, don't send redirect if forwarding using a default route 1166 * or a route modified by a redirect. 1167 */ 1168 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1169 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1170 !in_nullhost(satosin(rt_key(rt))->sin_addr) && 1171 ipsendredirects && !srcrt) { 1172 if (rt->rt_ifa && 1173 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1174 ifatoia(rt->rt_ifa)->ia_subnet) { 1175 if (rt->rt_flags & RTF_GATEWAY) 1176 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1177 else 1178 dest = ip->ip_dst.s_addr; 1179 /* Router requirements says to only send host redirects */ 1180 type = ICMP_REDIRECT; 1181 code = ICMP_REDIRECT_HOST; 1182#ifdef DIAGNOSTIC 1183 if (ipprintfs) 1184 printf("redirect (%d) to %x\n", code, (u_int32_t)dest); 1185#endif 1186 } 1187 } 1188 1189 error = ip_output(m, (struct mbuf *)0, &ipforward_rt, 1190 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 0); 1191 if (error) 1192 ipstat.ips_cantforward++; 1193 else { 1194 ipstat.ips_forward++; 1195 if (type) 1196 ipstat.ips_redirectsent++; 1197 else { 1198 if (mcopy) { 1199#ifdef GATEWAY 1200 ipflow_create(&ipforward_rt, mcopy); 1201#endif 1202 m_freem(mcopy); 1203 } 1204 return; 1205 } 1206 } 1207 if (mcopy == NULL) 1208 return; 1209 destifp = NULL; 1210 1211 switch (error) { 1212 1213 case 0: /* forwarded, but need redirect */ 1214 /* type, code set above */ 1215 break; 1216 1217 case ENETUNREACH: /* shouldn't happen, checked above */ 1218 case EHOSTUNREACH: 1219 case ENETDOWN: 1220 case EHOSTDOWN: 1221 default: 1222 type = ICMP_UNREACH; 1223 code = ICMP_UNREACH_HOST; 1224 break; 1225 1226 case EMSGSIZE: 1227 type = ICMP_UNREACH; 1228 code = ICMP_UNREACH_NEEDFRAG; 1229 if (ipforward_rt.ro_rt) 1230 destifp = ipforward_rt.ro_rt->rt_ifp; 1231 ipstat.ips_cantfrag++; 1232 break; 1233 1234 case ENOBUFS: 1235 type = ICMP_SOURCEQUENCH; 1236 code = 0; 1237 break; 1238 } 1239 icmp_error(mcopy, type, code, dest, destifp); 1240} 1241 1242void 1243ip_savecontrol(inp, mp, ip, m) 1244 register struct inpcb *inp; 1245 register struct mbuf **mp; 1246 register struct ip *ip; 1247 register struct mbuf *m; 1248{ 1249 1250 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 1251 struct timeval tv; 1252 1253 microtime(&tv); 1254 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1255 SCM_TIMESTAMP, SOL_SOCKET); 1256 if (*mp) 1257 mp = &(*mp)->m_next; 1258 } 1259 if (inp->inp_flags & INP_RECVDSTADDR) { 1260 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst, 1261 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 1262 if (*mp) 1263 mp = &(*mp)->m_next; 1264 } 1265#ifdef notyet 1266 /* 1267 * XXX 1268 * Moving these out of udp_input() made them even more broken 1269 * than they already were. 1270 * - fenner@parc.xerox.com 1271 */ 1272 /* options were tossed already */ 1273 if (inp->inp_flags & INP_RECVOPTS) { 1274 *mp = sbcreatecontrol((caddr_t) opts_deleted_above, 1275 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 1276 if (*mp) 1277 mp = &(*mp)->m_next; 1278 } 1279 /* ip_srcroute doesn't do what we want here, need to fix */ 1280 if (inp->inp_flags & INP_RECVRETOPTS) { 1281 *mp = sbcreatecontrol((caddr_t) ip_srcroute(), 1282 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 1283 if (*mp) 1284 mp = &(*mp)->m_next; 1285 } 1286#endif 1287 if (inp->inp_flags & INP_RECVIF) { 1288 struct sockaddr_dl sdl; 1289 1290 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]); 1291 sdl.sdl_family = AF_LINK; 1292 sdl.sdl_index = m->m_pkthdr.rcvif ? 1293 m->m_pkthdr.rcvif->if_index : 0; 1294 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0; 1295 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len, 1296 IP_RECVIF, IPPROTO_IP); 1297 if (*mp) 1298 mp = &(*mp)->m_next; 1299 } 1300} 1301 1302int 1303ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 1304 int *name; 1305 u_int namelen; 1306 void *oldp; 1307 size_t *oldlenp; 1308 void *newp; 1309 size_t newlen; 1310{ 1311 extern int subnetsarelocal; 1312 1313 int error, old; 1314 1315 /* All sysctl names at this level are terminal. */ 1316 if (namelen != 1) 1317 return (ENOTDIR); 1318 1319 switch (name[0]) { 1320 case IPCTL_FORWARDING: 1321 return (sysctl_int(oldp, oldlenp, newp, newlen, &ipforwarding)); 1322 case IPCTL_SENDREDIRECTS: 1323 return (sysctl_int(oldp, oldlenp, newp, newlen, 1324 &ipsendredirects)); 1325 case IPCTL_DEFTTL: 1326 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_defttl)); 1327#ifdef notyet 1328 case IPCTL_DEFMTU: 1329 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu)); 1330#endif 1331 case IPCTL_FORWSRCRT: 1332 /* Don't allow this to change in a secure environment. */ 1333 if (securelevel > 0) 1334 return (sysctl_rdint(oldp, oldlenp, newp, 1335 ip_forwsrcrt)); 1336 else 1337 return (sysctl_int(oldp, oldlenp, newp, newlen, 1338 &ip_forwsrcrt)); 1339 case IPCTL_DIRECTEDBCAST: 1340 return (sysctl_int(oldp, oldlenp, newp, newlen, 1341 &ip_directedbcast)); 1342 case IPCTL_ALLOWSRCRT: 1343 return (sysctl_int(oldp, oldlenp, newp, newlen, 1344 &ip_allowsrcrt)); 1345 case IPCTL_SUBNETSARELOCAL: 1346 return (sysctl_int(oldp, oldlenp, newp, newlen, 1347 &subnetsarelocal)); 1348 case IPCTL_MTUDISC: 1349 error = sysctl_int(oldp, oldlenp, newp, newlen, 1350 &ip_mtudisc); 1351 if (ip_mtudisc != 0 && ip_mtudisc_timeout_q == NULL) { 1352 ip_mtudisc_timeout_q = 1353 rt_timer_queue_create(ip_mtudisc_timeout); 1354 } else if (ip_mtudisc == 0 && ip_mtudisc_timeout_q != NULL) { 1355 rt_timer_queue_destroy(ip_mtudisc_timeout_q, TRUE); 1356 ip_mtudisc_timeout_q = NULL; 1357 } 1358 return error; 1359 case IPCTL_ANONPORTMIN: 1360 old = anonportmin; 1361 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmin); 1362 if (anonportmin >= anonportmax || anonportmin > 65535 1363#ifndef IPNOPRIVPORTS 1364 || anonportmin < IPPORT_RESERVED 1365#endif 1366 ) { 1367 anonportmin = old; 1368 return (EINVAL); 1369 } 1370 return (error); 1371 case IPCTL_ANONPORTMAX: 1372 old = anonportmax; 1373 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmax); 1374 if (anonportmin >= anonportmax || anonportmax > 65535 1375#ifndef IPNOPRIVPORTS 1376 || anonportmax < IPPORT_RESERVED 1377#endif 1378 ) { 1379 anonportmax = old; 1380 return (EINVAL); 1381 } 1382 return (error); 1383 case IPCTL_MTUDISCTIMEOUT: 1384 error = sysctl_int(oldp, oldlenp, newp, newlen, 1385 &ip_mtudisc_timeout); 1386 if (ip_mtudisc_timeout_q != NULL) 1387 rt_timer_queue_change(ip_mtudisc_timeout_q, 1388 ip_mtudisc_timeout); 1389 return (error); 1390 default: 1391 return (EOPNOTSUPP); 1392 } 1393 /* NOTREACHED */ 1394} 1395