ip_input.c revision 1.59
1/* $NetBSD: ip_input.c,v 1.59 1998/03/19 15:46:43 mrg 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_mrouting.h" 76 77#include <sys/param.h> 78#include <sys/systm.h> 79#include <sys/malloc.h> 80#include <sys/mbuf.h> 81#include <sys/domain.h> 82#include <sys/protosw.h> 83#include <sys/socket.h> 84#include <sys/socketvar.h> 85#include <sys/errno.h> 86#include <sys/time.h> 87#include <sys/kernel.h> 88#include <sys/proc.h> 89 90#include <vm/vm.h> 91#include <sys/sysctl.h> 92 93#include <net/if.h> 94#include <net/if_dl.h> 95#include <net/route.h> 96#include <net/pfil.h> 97 98#include <netinet/in.h> 99#include <netinet/in_systm.h> 100#include <netinet/ip.h> 101#include <netinet/in_pcb.h> 102#include <netinet/in_var.h> 103#include <netinet/ip_var.h> 104#include <netinet/ip_icmp.h> 105 106#ifndef IPFORWARDING 107#ifdef GATEWAY 108#define IPFORWARDING 1 /* forward IP packets not for us */ 109#else /* GATEWAY */ 110#define IPFORWARDING 0 /* don't forward IP packets not for us */ 111#endif /* GATEWAY */ 112#endif /* IPFORWARDING */ 113#ifndef IPSENDREDIRECTS 114#define IPSENDREDIRECTS 1 115#endif 116#ifndef IPFORWSRCRT 117#define IPFORWSRCRT 1 /* forward source-routed packets */ 118#endif 119#ifndef IPALLOWSRCRT 120#define IPALLOWSRCRT 1 /* allow source-routed packets */ 121#endif 122#ifndef IPMTUDISC 123#define IPMTUDISC 0 124#endif 125 126/* 127 * Note: DIRECTED_BROADCAST is handled this way so that previous 128 * configuration using this option will Just Work. 129 */ 130#ifndef IPDIRECTEDBCAST 131#ifdef DIRECTED_BROADCAST 132#define IPDIRECTEDBCAST 1 133#else 134#define IPDIRECTEDBCAST 0 135#endif /* DIRECTED_BROADCAST */ 136#endif /* IPDIRECTEDBCAST */ 137int ipforwarding = IPFORWARDING; 138int ipsendredirects = IPSENDREDIRECTS; 139int ip_defttl = IPDEFTTL; 140int ip_forwsrcrt = IPFORWSRCRT; 141int ip_directedbcast = IPDIRECTEDBCAST; 142int ip_allowsrcrt = IPALLOWSRCRT; 143int ip_mtudisc = IPMTUDISC; 144#ifdef DIAGNOSTIC 145int ipprintfs = 0; 146#endif 147 148extern struct domain inetdomain; 149extern struct protosw inetsw[]; 150u_char ip_protox[IPPROTO_MAX]; 151int ipqmaxlen = IFQ_MAXLEN; 152struct in_ifaddrhead in_ifaddr; 153struct in_ifaddrhashhead *in_ifaddrhashtbl; 154struct ifqueue ipintrq; 155 156/* 157 * We need to save the IP options in case a protocol wants to respond 158 * to an incoming packet over the same route if the packet got here 159 * using IP source routing. This allows connection establishment and 160 * maintenance when the remote end is on a network that is not known 161 * to us. 162 */ 163int ip_nhops = 0; 164static struct ip_srcrt { 165 struct in_addr dst; /* final destination */ 166 char nop; /* one NOP to align */ 167 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */ 168 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)]; 169} ip_srcrt; 170 171static void save_rte __P((u_char *, struct in_addr)); 172 173/* 174 * IP initialization: fill in IP protocol switch table. 175 * All protocols not implemented in kernel go to raw IP protocol handler. 176 */ 177void 178ip_init() 179{ 180 register struct protosw *pr; 181 register int i; 182 183 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); 184 if (pr == 0) 185 panic("ip_init"); 186 for (i = 0; i < IPPROTO_MAX; i++) 187 ip_protox[i] = pr - inetsw; 188 for (pr = inetdomain.dom_protosw; 189 pr < inetdomain.dom_protoswNPROTOSW; pr++) 190 if (pr->pr_domain->dom_family == PF_INET && 191 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 192 ip_protox[pr->pr_protocol] = pr - inetsw; 193 LIST_INIT(&ipq); 194 ip_id = time.tv_sec & 0xffff; 195 ipintrq.ifq_maxlen = ipqmaxlen; 196 TAILQ_INIT(&in_ifaddr); 197 in_ifaddrhashtbl = 198 hashinit(IN_IFADDR_HASH_SIZE, M_IFADDR, M_WAITOK, &in_ifaddrhash); 199} 200 201struct sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET }; 202struct route ipforward_rt; 203 204/* 205 * Ip input routine. Checksum and byte swap header. If fragmented 206 * try to reassemble. Process options. Pass to next level. 207 */ 208void 209ipintr() 210{ 211 register struct ip *ip = NULL; 212 register struct mbuf *m; 213 register struct ipq *fp; 214 register struct in_ifaddr *ia; 215 register struct ifaddr *ifa; 216 struct ipqent *ipqe; 217 int hlen = 0, mff, len, s; 218#ifdef PFIL_HOOKS 219 struct packet_filter_hook *pfh; 220 struct mbuf *m0; 221 int rv; 222#endif /* PFIL_HOOKS */ 223 224next: 225 /* 226 * Get next datagram off input queue and get IP header 227 * in first mbuf. 228 */ 229 s = splimp(); 230 IF_DEQUEUE(&ipintrq, m); 231 splx(s); 232 if (m == 0) 233 return; 234#ifdef DIAGNOSTIC 235 if ((m->m_flags & M_PKTHDR) == 0) 236 panic("ipintr no HDR"); 237#endif 238 /* 239 * If no IP addresses have been set yet but the interfaces 240 * are receiving, can't do anything with incoming packets yet. 241 */ 242 if (in_ifaddr.tqh_first == 0) 243 goto bad; 244 ipstat.ips_total++; 245 if (m->m_len < sizeof (struct ip) && 246 (m = m_pullup(m, sizeof (struct ip))) == 0) { 247 ipstat.ips_toosmall++; 248 goto next; 249 } 250 ip = mtod(m, struct ip *); 251 if (ip->ip_v != IPVERSION) { 252 ipstat.ips_badvers++; 253 goto bad; 254 } 255 hlen = ip->ip_hl << 2; 256 if (hlen < sizeof(struct ip)) { /* minimum header length */ 257 ipstat.ips_badhlen++; 258 goto bad; 259 } 260 if (hlen > m->m_len) { 261 if ((m = m_pullup(m, hlen)) == 0) { 262 ipstat.ips_badhlen++; 263 goto next; 264 } 265 ip = mtod(m, struct ip *); 266 } 267 if ((ip->ip_sum = in_cksum(m, hlen)) != 0) { 268 ipstat.ips_badsum++; 269 goto bad; 270 } 271 272 /* 273 * Convert fields to host representation. 274 */ 275 NTOHS(ip->ip_len); 276 NTOHS(ip->ip_id); 277 NTOHS(ip->ip_off); 278 len = ip->ip_len; 279 280 /* 281 * Check that the amount of data in the buffers 282 * is as at least much as the IP header would have us expect. 283 * Trim mbufs if longer than we expect. 284 * Drop packet if shorter than we expect. 285 */ 286 if (m->m_pkthdr.len < len) { 287 ipstat.ips_tooshort++; 288 goto bad; 289 } 290 if (m->m_pkthdr.len > len) { 291 if (m->m_len == m->m_pkthdr.len) { 292 m->m_len = len; 293 m->m_pkthdr.len = len; 294 } else 295 m_adj(m, len - m->m_pkthdr.len); 296 } 297 298#ifdef PFIL_HOOKS 299 /* 300 * Run through list of hooks for input packets. 301 */ 302 m0 = m; 303 for (pfh = pfil_hook_get(PFIL_IN); pfh; pfh = pfh->pfil_link.tqe_next) 304 if (pfh->pfil_func) { 305 rv = pfh->pfil_func(ip, hlen, m->m_pkthdr.rcvif, 0, &m0); 306 if (rv) 307 goto next; 308 ip = mtod(m = m0, struct ip *); 309 } 310#endif /* PFIL_HOOKS */ 311 312 /* 313 * Process options and, if not destined for us, 314 * ship it on. ip_dooptions returns 1 when an 315 * error was detected (causing an icmp message 316 * to be sent and the original packet to be freed). 317 */ 318 ip_nhops = 0; /* for source routed packets */ 319 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 320 goto next; 321 322 /* 323 * Check our list of addresses, to see if the packet is for us. 324 */ 325 INADDR_TO_IA(ip->ip_dst, ia); 326 if (ia != NULL) goto ours; 327 if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 328 for (ifa = m->m_pkthdr.rcvif->if_addrlist.tqh_first; 329 ifa != NULL; ifa = ifa->ifa_list.tqe_next) { 330 if (ifa->ifa_addr->sa_family != AF_INET) continue; 331 ia = ifatoia(ifa); 332 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 333 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 334 /* 335 * Look for all-0's host part (old broadcast addr), 336 * either for subnet or net. 337 */ 338 ip->ip_dst.s_addr == ia->ia_subnet || 339 ip->ip_dst.s_addr == ia->ia_net) 340 goto ours; 341 /* 342 * An interface with IP address zero accepts 343 * all packets that arrive on that interface. 344 */ 345 if (in_nullhost(ia->ia_addr.sin_addr)) 346 goto ours; 347 } 348 } 349 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 350 struct in_multi *inm; 351#ifdef MROUTING 352 extern struct socket *ip_mrouter; 353 354 if (m->m_flags & M_EXT) { 355 if ((m = m_pullup(m, hlen)) == 0) { 356 ipstat.ips_toosmall++; 357 goto next; 358 } 359 ip = mtod(m, struct ip *); 360 } 361 362 if (ip_mrouter) { 363 /* 364 * If we are acting as a multicast router, all 365 * incoming multicast packets are passed to the 366 * kernel-level multicast forwarding function. 367 * The packet is returned (relatively) intact; if 368 * ip_mforward() returns a non-zero value, the packet 369 * must be discarded, else it may be accepted below. 370 * 371 * (The IP ident field is put in the same byte order 372 * as expected when ip_mforward() is called from 373 * ip_output().) 374 */ 375 ip->ip_id = htons(ip->ip_id); 376 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 377 ipstat.ips_cantforward++; 378 m_freem(m); 379 goto next; 380 } 381 ip->ip_id = ntohs(ip->ip_id); 382 383 /* 384 * The process-level routing demon needs to receive 385 * all multicast IGMP packets, whether or not this 386 * host belongs to their destination groups. 387 */ 388 if (ip->ip_p == IPPROTO_IGMP) 389 goto ours; 390 ipstat.ips_forward++; 391 } 392#endif 393 /* 394 * See if we belong to the destination multicast group on the 395 * arrival interface. 396 */ 397 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 398 if (inm == NULL) { 399 ipstat.ips_cantforward++; 400 m_freem(m); 401 goto next; 402 } 403 goto ours; 404 } 405 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 406 in_nullhost(ip->ip_dst)) 407 goto ours; 408 409 /* 410 * Not for us; forward if possible and desirable. 411 */ 412 if (ipforwarding == 0) { 413 ipstat.ips_cantforward++; 414 m_freem(m); 415 } else 416 ip_forward(m, 0); 417 goto next; 418 419ours: 420 /* 421 * If offset or IP_MF are set, must reassemble. 422 * Otherwise, nothing need be done. 423 * (We could look in the reassembly queue to see 424 * if the packet was previously fragmented, 425 * but it's not worth the time; just let them time out.) 426 */ 427 if (ip->ip_off & ~(IP_DF|IP_RF)) { 428 /* 429 * Look for queue of fragments 430 * of this datagram. 431 */ 432 for (fp = ipq.lh_first; fp != NULL; fp = fp->ipq_q.le_next) 433 if (ip->ip_id == fp->ipq_id && 434 in_hosteq(ip->ip_src, fp->ipq_src) && 435 in_hosteq(ip->ip_dst, fp->ipq_dst) && 436 ip->ip_p == fp->ipq_p) 437 goto found; 438 fp = 0; 439found: 440 441 /* 442 * Adjust ip_len to not reflect header, 443 * set ipqe_mff if more fragments are expected, 444 * convert offset of this to bytes. 445 */ 446 ip->ip_len -= hlen; 447 mff = (ip->ip_off & IP_MF) != 0; 448 if (mff) { 449 /* 450 * Make sure that fragments have a data length 451 * that's a non-zero multiple of 8 bytes. 452 */ 453 if (ip->ip_len == 0 || (ip->ip_len & 0x7) != 0) { 454 ipstat.ips_badfrags++; 455 goto bad; 456 } 457 } 458 ip->ip_off <<= 3; 459 460 /* 461 * If datagram marked as having more fragments 462 * or if this is not the first fragment, 463 * attempt reassembly; if it succeeds, proceed. 464 */ 465 if (mff || ip->ip_off) { 466 ipstat.ips_fragments++; 467 MALLOC(ipqe, struct ipqent *, sizeof (struct ipqent), 468 M_IPQ, M_NOWAIT); 469 if (ipqe == NULL) { 470 ipstat.ips_rcvmemdrop++; 471 goto bad; 472 } 473 ipqe->ipqe_mff = mff; 474 ipqe->ipqe_m = m; 475 ipqe->ipqe_ip = ip; 476 m = ip_reass(ipqe, fp); 477 if (m == 0) 478 goto next; 479 ipstat.ips_reassembled++; 480 ip = mtod(m, struct ip *); 481 } else 482 if (fp) 483 ip_freef(fp); 484 } else 485 ip->ip_len -= hlen; 486 487 /* 488 * Switch out to protocol's input routine. 489 */ 490 ipstat.ips_delivered++; 491 (*inetsw[ip_protox[ip->ip_p]].pr_input)(m, hlen); 492 goto next; 493bad: 494 m_freem(m); 495 goto next; 496} 497 498/* 499 * Take incoming datagram fragment and try to 500 * reassemble it into whole datagram. If a chain for 501 * reassembly of this datagram already exists, then it 502 * is given as fp; otherwise have to make a chain. 503 */ 504struct mbuf * 505ip_reass(ipqe, fp) 506 register struct ipqent *ipqe; 507 register struct ipq *fp; 508{ 509 register struct mbuf *m = ipqe->ipqe_m; 510 register struct ipqent *nq, *p, *q; 511 struct ip *ip; 512 struct mbuf *t; 513 int hlen = ipqe->ipqe_ip->ip_hl << 2; 514 int i, next; 515 516 /* 517 * Presence of header sizes in mbufs 518 * would confuse code below. 519 */ 520 m->m_data += hlen; 521 m->m_len -= hlen; 522 523 /* 524 * If first fragment to arrive, create a reassembly queue. 525 */ 526 if (fp == 0) { 527 MALLOC(fp, struct ipq *, sizeof (struct ipq), 528 M_FTABLE, M_NOWAIT); 529 if (fp == NULL) 530 goto dropfrag; 531 LIST_INSERT_HEAD(&ipq, fp, ipq_q); 532 fp->ipq_ttl = IPFRAGTTL; 533 fp->ipq_p = ipqe->ipqe_ip->ip_p; 534 fp->ipq_id = ipqe->ipqe_ip->ip_id; 535 LIST_INIT(&fp->ipq_fragq); 536 fp->ipq_src = ipqe->ipqe_ip->ip_src; 537 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 538 p = NULL; 539 goto insert; 540 } 541 542 /* 543 * Find a segment which begins after this one does. 544 */ 545 for (p = NULL, q = fp->ipq_fragq.lh_first; q != NULL; 546 p = q, q = q->ipqe_q.le_next) 547 if (q->ipqe_ip->ip_off > ipqe->ipqe_ip->ip_off) 548 break; 549 550 /* 551 * If there is a preceding segment, it may provide some of 552 * our data already. If so, drop the data from the incoming 553 * segment. If it provides all of our data, drop us. 554 */ 555 if (p != NULL) { 556 i = p->ipqe_ip->ip_off + p->ipqe_ip->ip_len - 557 ipqe->ipqe_ip->ip_off; 558 if (i > 0) { 559 if (i >= ipqe->ipqe_ip->ip_len) 560 goto dropfrag; 561 m_adj(ipqe->ipqe_m, i); 562 ipqe->ipqe_ip->ip_off += i; 563 ipqe->ipqe_ip->ip_len -= i; 564 } 565 } 566 567 /* 568 * While we overlap succeeding segments trim them or, 569 * if they are completely covered, dequeue them. 570 */ 571 for (; q != NULL && ipqe->ipqe_ip->ip_off + ipqe->ipqe_ip->ip_len > 572 q->ipqe_ip->ip_off; q = nq) { 573 i = (ipqe->ipqe_ip->ip_off + ipqe->ipqe_ip->ip_len) - 574 q->ipqe_ip->ip_off; 575 if (i < q->ipqe_ip->ip_len) { 576 q->ipqe_ip->ip_len -= i; 577 q->ipqe_ip->ip_off += i; 578 m_adj(q->ipqe_m, i); 579 break; 580 } 581 nq = q->ipqe_q.le_next; 582 m_freem(q->ipqe_m); 583 LIST_REMOVE(q, ipqe_q); 584 FREE(q, M_IPQ); 585 } 586 587insert: 588 /* 589 * Stick new segment in its place; 590 * check for complete reassembly. 591 */ 592 if (p == NULL) { 593 LIST_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 594 } else { 595 LIST_INSERT_AFTER(p, ipqe, ipqe_q); 596 } 597 next = 0; 598 for (p = NULL, q = fp->ipq_fragq.lh_first; q != NULL; 599 p = q, q = q->ipqe_q.le_next) { 600 if (q->ipqe_ip->ip_off != next) 601 return (0); 602 next += q->ipqe_ip->ip_len; 603 } 604 if (p->ipqe_mff) 605 return (0); 606 607 /* 608 * Reassembly is complete. Check for a bogus message size and 609 * concatenate fragments. 610 */ 611 q = fp->ipq_fragq.lh_first; 612 ip = q->ipqe_ip; 613 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 614 ipstat.ips_toolong++; 615 ip_freef(fp); 616 return (0); 617 } 618 m = q->ipqe_m; 619 t = m->m_next; 620 m->m_next = 0; 621 m_cat(m, t); 622 nq = q->ipqe_q.le_next; 623 FREE(q, M_IPQ); 624 for (q = nq; q != NULL; q = nq) { 625 t = q->ipqe_m; 626 nq = q->ipqe_q.le_next; 627 FREE(q, M_IPQ); 628 m_cat(m, t); 629 } 630 631 /* 632 * Create header for new ip packet by 633 * modifying header of first packet; 634 * dequeue and discard fragment reassembly header. 635 * Make header visible. 636 */ 637 ip->ip_len = next; 638 ip->ip_src = fp->ipq_src; 639 ip->ip_dst = fp->ipq_dst; 640 LIST_REMOVE(fp, ipq_q); 641 FREE(fp, M_FTABLE); 642 m->m_len += (ip->ip_hl << 2); 643 m->m_data -= (ip->ip_hl << 2); 644 /* some debugging cruft by sklower, below, will go away soon */ 645 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 646 register int plen = 0; 647 for (t = m; t; t = t->m_next) 648 plen += t->m_len; 649 m->m_pkthdr.len = plen; 650 } 651 return (m); 652 653dropfrag: 654 ipstat.ips_fragdropped++; 655 m_freem(m); 656 FREE(ipqe, M_IPQ); 657 return (0); 658} 659 660/* 661 * Free a fragment reassembly header and all 662 * associated datagrams. 663 */ 664void 665ip_freef(fp) 666 struct ipq *fp; 667{ 668 register struct ipqent *q, *p; 669 670 for (q = fp->ipq_fragq.lh_first; q != NULL; q = p) { 671 p = q->ipqe_q.le_next; 672 m_freem(q->ipqe_m); 673 LIST_REMOVE(q, ipqe_q); 674 FREE(q, M_IPQ); 675 } 676 LIST_REMOVE(fp, ipq_q); 677 FREE(fp, M_FTABLE); 678} 679 680/* 681 * IP timer processing; 682 * if a timer expires on a reassembly 683 * queue, discard it. 684 */ 685void 686ip_slowtimo() 687{ 688 register struct ipq *fp, *nfp; 689 int s = splsoftnet(); 690 691 for (fp = ipq.lh_first; fp != NULL; fp = nfp) { 692 nfp = fp->ipq_q.le_next; 693 if (--fp->ipq_ttl == 0) { 694 ipstat.ips_fragtimeout++; 695 ip_freef(fp); 696 } 697 } 698 splx(s); 699} 700 701/* 702 * Drain off all datagram fragments. 703 */ 704void 705ip_drain() 706{ 707 708 while (ipq.lh_first != NULL) { 709 ipstat.ips_fragdropped++; 710 ip_freef(ipq.lh_first); 711 } 712} 713 714/* 715 * Do option processing on a datagram, 716 * possibly discarding it if bad options are encountered, 717 * or forwarding it if source-routed. 718 * Returns 1 if packet has been forwarded/freed, 719 * 0 if the packet should be processed further. 720 */ 721int 722ip_dooptions(m) 723 struct mbuf *m; 724{ 725 register struct ip *ip = mtod(m, struct ip *); 726 register u_char *cp; 727 register struct ip_timestamp *ipt; 728 register struct in_ifaddr *ia; 729 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 730 struct in_addr *sin, dst; 731 n_time ntime; 732 733 dst = ip->ip_dst; 734 cp = (u_char *)(ip + 1); 735 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 736 for (; cnt > 0; cnt -= optlen, cp += optlen) { 737 opt = cp[IPOPT_OPTVAL]; 738 if (opt == IPOPT_EOL) 739 break; 740 if (opt == IPOPT_NOP) 741 optlen = 1; 742 else { 743 optlen = cp[IPOPT_OLEN]; 744 if (optlen <= 0 || optlen > cnt) { 745 code = &cp[IPOPT_OLEN] - (u_char *)ip; 746 goto bad; 747 } 748 } 749 switch (opt) { 750 751 default: 752 break; 753 754 /* 755 * Source routing with record. 756 * Find interface with current destination address. 757 * If none on this machine then drop if strictly routed, 758 * or do nothing if loosely routed. 759 * Record interface address and bring up next address 760 * component. If strictly routed make sure next 761 * address is on directly accessible net. 762 */ 763 case IPOPT_LSRR: 764 case IPOPT_SSRR: 765 if (ip_allowsrcrt == 0) { 766 type = ICMP_UNREACH; 767 code = ICMP_UNREACH_NET_PROHIB; 768 goto bad; 769 } 770 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 771 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 772 goto bad; 773 } 774 ipaddr.sin_addr = ip->ip_dst; 775 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 776 if (ia == 0) { 777 if (opt == IPOPT_SSRR) { 778 type = ICMP_UNREACH; 779 code = ICMP_UNREACH_SRCFAIL; 780 goto bad; 781 } 782 /* 783 * Loose routing, and not at next destination 784 * yet; nothing to do except forward. 785 */ 786 break; 787 } 788 off--; /* 0 origin */ 789 if (off > optlen - sizeof(struct in_addr)) { 790 /* 791 * End of source route. Should be for us. 792 */ 793 save_rte(cp, ip->ip_src); 794 break; 795 } 796 /* 797 * locate outgoing interface 798 */ 799 bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr, 800 sizeof(ipaddr.sin_addr)); 801 if (opt == IPOPT_SSRR) { 802#define INA struct in_ifaddr * 803#define SA struct sockaddr * 804 ia = (INA)ifa_ifwithladdr((SA)&ipaddr); 805 } else 806 ia = ip_rtaddr(ipaddr.sin_addr); 807 if (ia == 0) { 808 type = ICMP_UNREACH; 809 code = ICMP_UNREACH_SRCFAIL; 810 goto bad; 811 } 812 ip->ip_dst = ipaddr.sin_addr; 813 bcopy((caddr_t)&ia->ia_addr.sin_addr, 814 (caddr_t)(cp + off), sizeof(struct in_addr)); 815 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 816 /* 817 * Let ip_intr's mcast routing check handle mcast pkts 818 */ 819 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 820 break; 821 822 case IPOPT_RR: 823 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 824 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 825 goto bad; 826 } 827 /* 828 * If no space remains, ignore. 829 */ 830 off--; /* 0 origin */ 831 if (off > optlen - sizeof(struct in_addr)) 832 break; 833 bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr, 834 sizeof(ipaddr.sin_addr)); 835 /* 836 * locate outgoing interface; if we're the destination, 837 * use the incoming interface (should be same). 838 */ 839 if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0 && 840 (ia = ip_rtaddr(ipaddr.sin_addr)) == 0) { 841 type = ICMP_UNREACH; 842 code = ICMP_UNREACH_HOST; 843 goto bad; 844 } 845 bcopy((caddr_t)&ia->ia_addr.sin_addr, 846 (caddr_t)(cp + off), sizeof(struct in_addr)); 847 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 848 break; 849 850 case IPOPT_TS: 851 code = cp - (u_char *)ip; 852 ipt = (struct ip_timestamp *)cp; 853 if (ipt->ipt_len < 5) 854 goto bad; 855 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 856 if (++ipt->ipt_oflw == 0) 857 goto bad; 858 break; 859 } 860 sin = (struct in_addr *)(cp + ipt->ipt_ptr - 1); 861 switch (ipt->ipt_flg) { 862 863 case IPOPT_TS_TSONLY: 864 break; 865 866 case IPOPT_TS_TSANDADDR: 867 if (ipt->ipt_ptr + sizeof(n_time) + 868 sizeof(struct in_addr) > ipt->ipt_len) 869 goto bad; 870 ipaddr.sin_addr = dst; 871 ia = (INA)ifaof_ifpforaddr((SA)&ipaddr, 872 m->m_pkthdr.rcvif); 873 if (ia == 0) 874 continue; 875 bcopy((caddr_t)&ia->ia_addr.sin_addr, 876 (caddr_t)sin, sizeof(struct in_addr)); 877 ipt->ipt_ptr += sizeof(struct in_addr); 878 break; 879 880 case IPOPT_TS_PRESPEC: 881 if (ipt->ipt_ptr + sizeof(n_time) + 882 sizeof(struct in_addr) > ipt->ipt_len) 883 goto bad; 884 bcopy((caddr_t)sin, (caddr_t)&ipaddr.sin_addr, 885 sizeof(struct in_addr)); 886 if (ifa_ifwithaddr((SA)&ipaddr) == 0) 887 continue; 888 ipt->ipt_ptr += sizeof(struct in_addr); 889 break; 890 891 default: 892 goto bad; 893 } 894 ntime = iptime(); 895 bcopy((caddr_t)&ntime, (caddr_t)cp + ipt->ipt_ptr - 1, 896 sizeof(n_time)); 897 ipt->ipt_ptr += sizeof(n_time); 898 } 899 } 900 if (forward) { 901 if (ip_forwsrcrt == 0) { 902 type = ICMP_UNREACH; 903 code = ICMP_UNREACH_SRCFAIL; 904 goto bad; 905 } 906 ip_forward(m, 1); 907 return (1); 908 } 909 return (0); 910bad: 911 ip->ip_len -= ip->ip_hl << 2; /* XXX icmp_error adds in hdr length */ 912 icmp_error(m, type, code, 0, 0); 913 ipstat.ips_badoptions++; 914 return (1); 915} 916 917/* 918 * Given address of next destination (final or next hop), 919 * return internet address info of interface to be used to get there. 920 */ 921struct in_ifaddr * 922ip_rtaddr(dst) 923 struct in_addr dst; 924{ 925 register struct sockaddr_in *sin; 926 927 sin = satosin(&ipforward_rt.ro_dst); 928 929 if (ipforward_rt.ro_rt == 0 || !in_hosteq(dst, sin->sin_addr)) { 930 if (ipforward_rt.ro_rt) { 931 RTFREE(ipforward_rt.ro_rt); 932 ipforward_rt.ro_rt = 0; 933 } 934 sin->sin_family = AF_INET; 935 sin->sin_len = sizeof(*sin); 936 sin->sin_addr = dst; 937 938 rtalloc(&ipforward_rt); 939 } 940 if (ipforward_rt.ro_rt == 0) 941 return ((struct in_ifaddr *)0); 942 return (ifatoia(ipforward_rt.ro_rt->rt_ifa)); 943} 944 945/* 946 * Save incoming source route for use in replies, 947 * to be picked up later by ip_srcroute if the receiver is interested. 948 */ 949void 950save_rte(option, dst) 951 u_char *option; 952 struct in_addr dst; 953{ 954 unsigned olen; 955 956 olen = option[IPOPT_OLEN]; 957#ifdef DIAGNOSTIC 958 if (ipprintfs) 959 printf("save_rte: olen %d\n", olen); 960#endif 961 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 962 return; 963 bcopy((caddr_t)option, (caddr_t)ip_srcrt.srcopt, olen); 964 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 965 ip_srcrt.dst = dst; 966} 967 968/* 969 * Retrieve incoming source route for use in replies, 970 * in the same form used by setsockopt. 971 * The first hop is placed before the options, will be removed later. 972 */ 973struct mbuf * 974ip_srcroute() 975{ 976 register struct in_addr *p, *q; 977 register struct mbuf *m; 978 979 if (ip_nhops == 0) 980 return ((struct mbuf *)0); 981 m = m_get(M_DONTWAIT, MT_SOOPTS); 982 if (m == 0) 983 return ((struct mbuf *)0); 984 985#define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 986 987 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 988 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 989 OPTSIZ; 990#ifdef DIAGNOSTIC 991 if (ipprintfs) 992 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 993#endif 994 995 /* 996 * First save first hop for return route 997 */ 998 p = &ip_srcrt.route[ip_nhops - 1]; 999 *(mtod(m, struct in_addr *)) = *p--; 1000#ifdef DIAGNOSTIC 1001 if (ipprintfs) 1002 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1003#endif 1004 1005 /* 1006 * Copy option fields and padding (nop) to mbuf. 1007 */ 1008 ip_srcrt.nop = IPOPT_NOP; 1009 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1010 bcopy((caddr_t)&ip_srcrt.nop, 1011 mtod(m, caddr_t) + sizeof(struct in_addr), OPTSIZ); 1012 q = (struct in_addr *)(mtod(m, caddr_t) + 1013 sizeof(struct in_addr) + OPTSIZ); 1014#undef OPTSIZ 1015 /* 1016 * Record return path as an IP source route, 1017 * reversing the path (pointers are now aligned). 1018 */ 1019 while (p >= ip_srcrt.route) { 1020#ifdef DIAGNOSTIC 1021 if (ipprintfs) 1022 printf(" %x", ntohl(q->s_addr)); 1023#endif 1024 *q++ = *p--; 1025 } 1026 /* 1027 * Last hop goes to final destination. 1028 */ 1029 *q = ip_srcrt.dst; 1030#ifdef DIAGNOSTIC 1031 if (ipprintfs) 1032 printf(" %x\n", ntohl(q->s_addr)); 1033#endif 1034 return (m); 1035} 1036 1037/* 1038 * Strip out IP options, at higher 1039 * level protocol in the kernel. 1040 * Second argument is buffer to which options 1041 * will be moved, and return value is their length. 1042 * XXX should be deleted; last arg currently ignored. 1043 */ 1044void 1045ip_stripoptions(m, mopt) 1046 register struct mbuf *m; 1047 struct mbuf *mopt; 1048{ 1049 register int i; 1050 struct ip *ip = mtod(m, struct ip *); 1051 register caddr_t opts; 1052 int olen; 1053 1054 olen = (ip->ip_hl<<2) - sizeof (struct ip); 1055 opts = (caddr_t)(ip + 1); 1056 i = m->m_len - (sizeof (struct ip) + olen); 1057 bcopy(opts + olen, opts, (unsigned)i); 1058 m->m_len -= olen; 1059 if (m->m_flags & M_PKTHDR) 1060 m->m_pkthdr.len -= olen; 1061 ip->ip_hl = sizeof(struct ip) >> 2; 1062} 1063 1064int inetctlerrmap[PRC_NCMDS] = { 1065 0, 0, 0, 0, 1066 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1067 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1068 EMSGSIZE, EHOSTUNREACH, 0, 0, 1069 0, 0, 0, 0, 1070 ENOPROTOOPT 1071}; 1072 1073/* 1074 * Forward a packet. If some error occurs return the sender 1075 * an icmp packet. Note we can't always generate a meaningful 1076 * icmp message because icmp doesn't have a large enough repertoire 1077 * of codes and types. 1078 * 1079 * If not forwarding, just drop the packet. This could be confusing 1080 * if ipforwarding was zero but some routing protocol was advancing 1081 * us as a gateway to somewhere. However, we must let the routing 1082 * protocol deal with that. 1083 * 1084 * The srcrt parameter indicates whether the packet is being forwarded 1085 * via a source route. 1086 */ 1087void 1088ip_forward(m, srcrt) 1089 struct mbuf *m; 1090 int srcrt; 1091{ 1092 register struct ip *ip = mtod(m, struct ip *); 1093 register struct sockaddr_in *sin; 1094 register struct rtentry *rt; 1095 int error, type = 0, code = 0; 1096 struct mbuf *mcopy; 1097 n_long dest; 1098 struct ifnet *destifp; 1099 1100 dest = 0; 1101#ifdef DIAGNOSTIC 1102 if (ipprintfs) 1103 printf("forward: src %x dst %x ttl %x\n", 1104 ip->ip_src.s_addr, ip->ip_dst.s_addr, ip->ip_ttl); 1105#endif 1106 if (m->m_flags & M_BCAST || in_canforward(ip->ip_dst) == 0) { 1107 ipstat.ips_cantforward++; 1108 m_freem(m); 1109 return; 1110 } 1111 HTONS(ip->ip_id); 1112 if (ip->ip_ttl <= IPTTLDEC) { 1113 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1114 return; 1115 } 1116 ip->ip_ttl -= IPTTLDEC; 1117 1118 sin = satosin(&ipforward_rt.ro_dst); 1119 if ((rt = ipforward_rt.ro_rt) == 0 || 1120 !in_hosteq(ip->ip_dst, sin->sin_addr)) { 1121 if (ipforward_rt.ro_rt) { 1122 RTFREE(ipforward_rt.ro_rt); 1123 ipforward_rt.ro_rt = 0; 1124 } 1125 sin->sin_family = AF_INET; 1126 sin->sin_len = sizeof(struct sockaddr_in); 1127 sin->sin_addr = ip->ip_dst; 1128 1129 rtalloc(&ipforward_rt); 1130 if (ipforward_rt.ro_rt == 0) { 1131 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0); 1132 return; 1133 } 1134 rt = ipforward_rt.ro_rt; 1135 } 1136 1137 /* 1138 * Save at most 68 bytes of the packet in case 1139 * we need to generate an ICMP message to the src. 1140 */ 1141 mcopy = m_copy(m, 0, imin((int)ip->ip_len, 68)); 1142 1143 /* 1144 * If forwarding packet using same interface that it came in on, 1145 * perhaps should send a redirect to sender to shortcut a hop. 1146 * Only send redirect if source is sending directly to us, 1147 * and if packet was not source routed (or has any options). 1148 * Also, don't send redirect if forwarding using a default route 1149 * or a route modified by a redirect. 1150 */ 1151 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1152 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1153 !in_nullhost(satosin(rt_key(rt))->sin_addr) && 1154 ipsendredirects && !srcrt) { 1155 if (rt->rt_ifa && 1156 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1157 ifatoia(rt->rt_ifa)->ia_subnet) { 1158 if (rt->rt_flags & RTF_GATEWAY) 1159 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1160 else 1161 dest = ip->ip_dst.s_addr; 1162 /* Router requirements says to only send host redirects */ 1163 type = ICMP_REDIRECT; 1164 code = ICMP_REDIRECT_HOST; 1165#ifdef DIAGNOSTIC 1166 if (ipprintfs) 1167 printf("redirect (%d) to %x\n", code, (u_int32_t)dest); 1168#endif 1169 } 1170 } 1171 1172 error = ip_output(m, (struct mbuf *)0, &ipforward_rt, 1173 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 0); 1174 if (error) 1175 ipstat.ips_cantforward++; 1176 else { 1177 ipstat.ips_forward++; 1178 if (type) 1179 ipstat.ips_redirectsent++; 1180 else { 1181 if (mcopy) 1182 m_freem(mcopy); 1183 return; 1184 } 1185 } 1186 if (mcopy == NULL) 1187 return; 1188 destifp = NULL; 1189 1190 switch (error) { 1191 1192 case 0: /* forwarded, but need redirect */ 1193 /* type, code set above */ 1194 break; 1195 1196 case ENETUNREACH: /* shouldn't happen, checked above */ 1197 case EHOSTUNREACH: 1198 case ENETDOWN: 1199 case EHOSTDOWN: 1200 default: 1201 type = ICMP_UNREACH; 1202 code = ICMP_UNREACH_HOST; 1203 break; 1204 1205 case EMSGSIZE: 1206 type = ICMP_UNREACH; 1207 code = ICMP_UNREACH_NEEDFRAG; 1208 if (ipforward_rt.ro_rt) 1209 destifp = ipforward_rt.ro_rt->rt_ifp; 1210 ipstat.ips_cantfrag++; 1211 break; 1212 1213 case ENOBUFS: 1214 type = ICMP_SOURCEQUENCH; 1215 code = 0; 1216 break; 1217 } 1218 icmp_error(mcopy, type, code, dest, destifp); 1219} 1220 1221void 1222ip_savecontrol(inp, mp, ip, m) 1223 register struct inpcb *inp; 1224 register struct mbuf **mp; 1225 register struct ip *ip; 1226 register struct mbuf *m; 1227{ 1228 1229 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 1230 struct timeval tv; 1231 1232 microtime(&tv); 1233 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1234 SCM_TIMESTAMP, SOL_SOCKET); 1235 if (*mp) 1236 mp = &(*mp)->m_next; 1237 } 1238 if (inp->inp_flags & INP_RECVDSTADDR) { 1239 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst, 1240 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 1241 if (*mp) 1242 mp = &(*mp)->m_next; 1243 } 1244#ifdef notyet 1245 /* 1246 * XXX 1247 * Moving these out of udp_input() made them even more broken 1248 * than they already were. 1249 * - fenner@parc.xerox.com 1250 */ 1251 /* options were tossed already */ 1252 if (inp->inp_flags & INP_RECVOPTS) { 1253 *mp = sbcreatecontrol((caddr_t) opts_deleted_above, 1254 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 1255 if (*mp) 1256 mp = &(*mp)->m_next; 1257 } 1258 /* ip_srcroute doesn't do what we want here, need to fix */ 1259 if (inp->inp_flags & INP_RECVRETOPTS) { 1260 *mp = sbcreatecontrol((caddr_t) ip_srcroute(), 1261 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 1262 if (*mp) 1263 mp = &(*mp)->m_next; 1264 } 1265#endif 1266 if (inp->inp_flags & INP_RECVIF) { 1267 struct sockaddr_dl sdl; 1268 1269 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]); 1270 sdl.sdl_family = AF_LINK; 1271 sdl.sdl_index = m->m_pkthdr.rcvif ? 1272 m->m_pkthdr.rcvif->if_index : 0; 1273 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0; 1274 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len, 1275 IP_RECVIF, IPPROTO_IP); 1276 if (*mp) 1277 mp = &(*mp)->m_next; 1278 } 1279} 1280 1281int 1282ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 1283 int *name; 1284 u_int namelen; 1285 void *oldp; 1286 size_t *oldlenp; 1287 void *newp; 1288 size_t newlen; 1289{ 1290 extern int subnetsarelocal; 1291 1292 int error, old; 1293 1294 /* All sysctl names at this level are terminal. */ 1295 if (namelen != 1) 1296 return (ENOTDIR); 1297 1298 switch (name[0]) { 1299 case IPCTL_FORWARDING: 1300 return (sysctl_int(oldp, oldlenp, newp, newlen, &ipforwarding)); 1301 case IPCTL_SENDREDIRECTS: 1302 return (sysctl_int(oldp, oldlenp, newp, newlen, 1303 &ipsendredirects)); 1304 case IPCTL_DEFTTL: 1305 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_defttl)); 1306#ifdef notyet 1307 case IPCTL_DEFMTU: 1308 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu)); 1309#endif 1310 case IPCTL_FORWSRCRT: 1311 /* Don't allow this to change in a secure environment. */ 1312 if (securelevel > 0) 1313 return (sysctl_rdint(oldp, oldlenp, newp, 1314 ip_forwsrcrt)); 1315 else 1316 return (sysctl_int(oldp, oldlenp, newp, newlen, 1317 &ip_forwsrcrt)); 1318 case IPCTL_DIRECTEDBCAST: 1319 return (sysctl_int(oldp, oldlenp, newp, newlen, 1320 &ip_directedbcast)); 1321 case IPCTL_ALLOWSRCRT: 1322 return (sysctl_int(oldp, oldlenp, newp, newlen, 1323 &ip_allowsrcrt)); 1324 case IPCTL_SUBNETSARELOCAL: 1325 return (sysctl_int(oldp, oldlenp, newp, newlen, 1326 &subnetsarelocal)); 1327 case IPCTL_MTUDISC: 1328 return (sysctl_int(oldp, oldlenp, newp, newlen, 1329 &ip_mtudisc)); 1330 case IPCTL_ANONPORTMIN: 1331 old = anonportmin; 1332 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmin); 1333 if (anonportmin >= anonportmax || anonportmin > 65535 1334#ifndef IPNOPRIVPORTS 1335 || anonportmin < IPPORT_RESERVED 1336#endif 1337 ) { 1338 anonportmin = old; 1339 return (EINVAL); 1340 } 1341 return (error); 1342 case IPCTL_ANONPORTMAX: 1343 old = anonportmax; 1344 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmax); 1345 if (anonportmin >= anonportmax || anonportmax > 65535 1346#ifndef IPNOPRIVPORTS 1347 || anonportmax < IPPORT_RESERVED 1348#endif 1349 ) { 1350 anonportmax = old; 1351 return (EINVAL); 1352 } 1353 return (error); 1354 default: 1355 return (EOPNOTSUPP); 1356 } 1357 /* NOTREACHED */ 1358} 1359