ip_input.c revision 1.64
1/* $NetBSD: ip_input.c,v 1.64 1998/05/01 03:23:24 thorpej 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 /* 313 * Assume that we can create a fast-forward IP flow entry 314 * based on this packet. 315 */ 316 m->m_flags |= M_CANFASTFWD; 317 318#ifdef PFIL_HOOKS 319 /* 320 * Run through list of hooks for input packets. If there are any 321 * filters which require that additional packets in the flow are 322 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 323 * Note that filters must _never_ set this flag, as another filter 324 * in the list may have previously cleared it. 325 */ 326 m0 = m; 327 for (pfh = pfil_hook_get(PFIL_IN); pfh; pfh = pfh->pfil_link.tqe_next) 328 if (pfh->pfil_func) { 329 rv = pfh->pfil_func(ip, hlen, m->m_pkthdr.rcvif, 0, &m0); 330 if (rv) 331 goto next; 332 ip = mtod(m = m0, struct ip *); 333 } 334#endif /* PFIL_HOOKS */ 335 336 /* 337 * Process options and, if not destined for us, 338 * ship it on. ip_dooptions returns 1 when an 339 * error was detected (causing an icmp message 340 * to be sent and the original packet to be freed). 341 */ 342 ip_nhops = 0; /* for source routed packets */ 343 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 344 goto next; 345 346 /* 347 * Check our list of addresses, to see if the packet is for us. 348 */ 349 INADDR_TO_IA(ip->ip_dst, ia); 350 if (ia != NULL) goto ours; 351 if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 352 for (ifa = m->m_pkthdr.rcvif->if_addrlist.tqh_first; 353 ifa != NULL; ifa = ifa->ifa_list.tqe_next) { 354 if (ifa->ifa_addr->sa_family != AF_INET) continue; 355 ia = ifatoia(ifa); 356 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 357 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 358 /* 359 * Look for all-0's host part (old broadcast addr), 360 * either for subnet or net. 361 */ 362 ip->ip_dst.s_addr == ia->ia_subnet || 363 ip->ip_dst.s_addr == ia->ia_net) 364 goto ours; 365 /* 366 * An interface with IP address zero accepts 367 * all packets that arrive on that interface. 368 */ 369 if (in_nullhost(ia->ia_addr.sin_addr)) 370 goto ours; 371 } 372 } 373 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 374 struct in_multi *inm; 375#ifdef MROUTING 376 extern struct socket *ip_mrouter; 377 378 if (m->m_flags & M_EXT) { 379 if ((m = m_pullup(m, hlen)) == 0) { 380 ipstat.ips_toosmall++; 381 goto next; 382 } 383 ip = mtod(m, struct ip *); 384 } 385 386 if (ip_mrouter) { 387 /* 388 * If we are acting as a multicast router, all 389 * incoming multicast packets are passed to the 390 * kernel-level multicast forwarding function. 391 * The packet is returned (relatively) intact; if 392 * ip_mforward() returns a non-zero value, the packet 393 * must be discarded, else it may be accepted below. 394 * 395 * (The IP ident field is put in the same byte order 396 * as expected when ip_mforward() is called from 397 * ip_output().) 398 */ 399 ip->ip_id = htons(ip->ip_id); 400 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 401 ipstat.ips_cantforward++; 402 m_freem(m); 403 goto next; 404 } 405 ip->ip_id = ntohs(ip->ip_id); 406 407 /* 408 * The process-level routing demon needs to receive 409 * all multicast IGMP packets, whether or not this 410 * host belongs to their destination groups. 411 */ 412 if (ip->ip_p == IPPROTO_IGMP) 413 goto ours; 414 ipstat.ips_forward++; 415 } 416#endif 417 /* 418 * See if we belong to the destination multicast group on the 419 * arrival interface. 420 */ 421 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 422 if (inm == NULL) { 423 ipstat.ips_cantforward++; 424 m_freem(m); 425 goto next; 426 } 427 goto ours; 428 } 429 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 430 in_nullhost(ip->ip_dst)) 431 goto ours; 432 433 /* 434 * Not for us; forward if possible and desirable. 435 */ 436 if (ipforwarding == 0) { 437 ipstat.ips_cantforward++; 438 m_freem(m); 439 } else 440 ip_forward(m, 0); 441 goto next; 442 443ours: 444 /* 445 * If offset or IP_MF are set, must reassemble. 446 * Otherwise, nothing need be done. 447 * (We could look in the reassembly queue to see 448 * if the packet was previously fragmented, 449 * but it's not worth the time; just let them time out.) 450 */ 451 if (ip->ip_off & ~(IP_DF|IP_RF)) { 452 /* 453 * Look for queue of fragments 454 * of this datagram. 455 */ 456 for (fp = ipq.lh_first; fp != NULL; fp = fp->ipq_q.le_next) 457 if (ip->ip_id == fp->ipq_id && 458 in_hosteq(ip->ip_src, fp->ipq_src) && 459 in_hosteq(ip->ip_dst, fp->ipq_dst) && 460 ip->ip_p == fp->ipq_p) 461 goto found; 462 fp = 0; 463found: 464 465 /* 466 * Adjust ip_len to not reflect header, 467 * set ipqe_mff if more fragments are expected, 468 * convert offset of this to bytes. 469 */ 470 ip->ip_len -= hlen; 471 mff = (ip->ip_off & IP_MF) != 0; 472 if (mff) { 473 /* 474 * Make sure that fragments have a data length 475 * that's a non-zero multiple of 8 bytes. 476 */ 477 if (ip->ip_len == 0 || (ip->ip_len & 0x7) != 0) { 478 ipstat.ips_badfrags++; 479 goto bad; 480 } 481 } 482 ip->ip_off <<= 3; 483 484 /* 485 * If datagram marked as having more fragments 486 * or if this is not the first fragment, 487 * attempt reassembly; if it succeeds, proceed. 488 */ 489 if (mff || ip->ip_off) { 490 ipstat.ips_fragments++; 491 MALLOC(ipqe, struct ipqent *, sizeof (struct ipqent), 492 M_IPQ, M_NOWAIT); 493 if (ipqe == NULL) { 494 ipstat.ips_rcvmemdrop++; 495 goto bad; 496 } 497 ipqe->ipqe_mff = mff; 498 ipqe->ipqe_m = m; 499 ipqe->ipqe_ip = ip; 500 m = ip_reass(ipqe, fp); 501 if (m == 0) 502 goto next; 503 ipstat.ips_reassembled++; 504 ip = mtod(m, struct ip *); 505 } else 506 if (fp) 507 ip_freef(fp); 508 } else 509 ip->ip_len -= hlen; 510 511 /* 512 * Switch out to protocol's input routine. 513 */ 514 ipstat.ips_delivered++; 515 (*inetsw[ip_protox[ip->ip_p]].pr_input)(m, hlen); 516 goto next; 517bad: 518 m_freem(m); 519 goto next; 520} 521 522/* 523 * Take incoming datagram fragment and try to 524 * reassemble it into whole datagram. If a chain for 525 * reassembly of this datagram already exists, then it 526 * is given as fp; otherwise have to make a chain. 527 */ 528struct mbuf * 529ip_reass(ipqe, fp) 530 register struct ipqent *ipqe; 531 register struct ipq *fp; 532{ 533 register struct mbuf *m = ipqe->ipqe_m; 534 register struct ipqent *nq, *p, *q; 535 struct ip *ip; 536 struct mbuf *t; 537 int hlen = ipqe->ipqe_ip->ip_hl << 2; 538 int i, next; 539 540 /* 541 * Presence of header sizes in mbufs 542 * would confuse code below. 543 */ 544 m->m_data += hlen; 545 m->m_len -= hlen; 546 547 /* 548 * If first fragment to arrive, create a reassembly queue. 549 */ 550 if (fp == 0) { 551 MALLOC(fp, struct ipq *, sizeof (struct ipq), 552 M_FTABLE, M_NOWAIT); 553 if (fp == NULL) 554 goto dropfrag; 555 LIST_INSERT_HEAD(&ipq, fp, ipq_q); 556 fp->ipq_ttl = IPFRAGTTL; 557 fp->ipq_p = ipqe->ipqe_ip->ip_p; 558 fp->ipq_id = ipqe->ipqe_ip->ip_id; 559 LIST_INIT(&fp->ipq_fragq); 560 fp->ipq_src = ipqe->ipqe_ip->ip_src; 561 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 562 p = NULL; 563 goto insert; 564 } 565 566 /* 567 * Find a segment which begins after this one does. 568 */ 569 for (p = NULL, q = fp->ipq_fragq.lh_first; q != NULL; 570 p = q, q = q->ipqe_q.le_next) 571 if (q->ipqe_ip->ip_off > ipqe->ipqe_ip->ip_off) 572 break; 573 574 /* 575 * If there is a preceding segment, it may provide some of 576 * our data already. If so, drop the data from the incoming 577 * segment. If it provides all of our data, drop us. 578 */ 579 if (p != NULL) { 580 i = p->ipqe_ip->ip_off + p->ipqe_ip->ip_len - 581 ipqe->ipqe_ip->ip_off; 582 if (i > 0) { 583 if (i >= ipqe->ipqe_ip->ip_len) 584 goto dropfrag; 585 m_adj(ipqe->ipqe_m, i); 586 ipqe->ipqe_ip->ip_off += i; 587 ipqe->ipqe_ip->ip_len -= i; 588 } 589 } 590 591 /* 592 * While we overlap succeeding segments trim them or, 593 * if they are completely covered, dequeue them. 594 */ 595 for (; q != NULL && ipqe->ipqe_ip->ip_off + ipqe->ipqe_ip->ip_len > 596 q->ipqe_ip->ip_off; q = nq) { 597 i = (ipqe->ipqe_ip->ip_off + ipqe->ipqe_ip->ip_len) - 598 q->ipqe_ip->ip_off; 599 if (i < q->ipqe_ip->ip_len) { 600 q->ipqe_ip->ip_len -= i; 601 q->ipqe_ip->ip_off += i; 602 m_adj(q->ipqe_m, i); 603 break; 604 } 605 nq = q->ipqe_q.le_next; 606 m_freem(q->ipqe_m); 607 LIST_REMOVE(q, ipqe_q); 608 FREE(q, M_IPQ); 609 } 610 611insert: 612 /* 613 * Stick new segment in its place; 614 * check for complete reassembly. 615 */ 616 if (p == NULL) { 617 LIST_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 618 } else { 619 LIST_INSERT_AFTER(p, ipqe, ipqe_q); 620 } 621 next = 0; 622 for (p = NULL, q = fp->ipq_fragq.lh_first; q != NULL; 623 p = q, q = q->ipqe_q.le_next) { 624 if (q->ipqe_ip->ip_off != next) 625 return (0); 626 next += q->ipqe_ip->ip_len; 627 } 628 if (p->ipqe_mff) 629 return (0); 630 631 /* 632 * Reassembly is complete. Check for a bogus message size and 633 * concatenate fragments. 634 */ 635 q = fp->ipq_fragq.lh_first; 636 ip = q->ipqe_ip; 637 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 638 ipstat.ips_toolong++; 639 ip_freef(fp); 640 return (0); 641 } 642 m = q->ipqe_m; 643 t = m->m_next; 644 m->m_next = 0; 645 m_cat(m, t); 646 nq = q->ipqe_q.le_next; 647 FREE(q, M_IPQ); 648 for (q = nq; q != NULL; q = nq) { 649 t = q->ipqe_m; 650 nq = q->ipqe_q.le_next; 651 FREE(q, M_IPQ); 652 m_cat(m, t); 653 } 654 655 /* 656 * Create header for new ip packet by 657 * modifying header of first packet; 658 * dequeue and discard fragment reassembly header. 659 * Make header visible. 660 */ 661 ip->ip_len = next; 662 ip->ip_src = fp->ipq_src; 663 ip->ip_dst = fp->ipq_dst; 664 LIST_REMOVE(fp, ipq_q); 665 FREE(fp, M_FTABLE); 666 m->m_len += (ip->ip_hl << 2); 667 m->m_data -= (ip->ip_hl << 2); 668 /* some debugging cruft by sklower, below, will go away soon */ 669 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 670 register int plen = 0; 671 for (t = m; t; t = t->m_next) 672 plen += t->m_len; 673 m->m_pkthdr.len = plen; 674 } 675 return (m); 676 677dropfrag: 678 ipstat.ips_fragdropped++; 679 m_freem(m); 680 FREE(ipqe, M_IPQ); 681 return (0); 682} 683 684/* 685 * Free a fragment reassembly header and all 686 * associated datagrams. 687 */ 688void 689ip_freef(fp) 690 struct ipq *fp; 691{ 692 register struct ipqent *q, *p; 693 694 for (q = fp->ipq_fragq.lh_first; q != NULL; q = p) { 695 p = q->ipqe_q.le_next; 696 m_freem(q->ipqe_m); 697 LIST_REMOVE(q, ipqe_q); 698 FREE(q, M_IPQ); 699 } 700 LIST_REMOVE(fp, ipq_q); 701 FREE(fp, M_FTABLE); 702} 703 704/* 705 * IP timer processing; 706 * if a timer expires on a reassembly 707 * queue, discard it. 708 */ 709void 710ip_slowtimo() 711{ 712 register struct ipq *fp, *nfp; 713 int s = splsoftnet(); 714 715 for (fp = ipq.lh_first; fp != NULL; fp = nfp) { 716 nfp = fp->ipq_q.le_next; 717 if (--fp->ipq_ttl == 0) { 718 ipstat.ips_fragtimeout++; 719 ip_freef(fp); 720 } 721 } 722#ifdef GATEWAY 723 ipflow_slowtimo(); 724#endif 725 splx(s); 726} 727 728/* 729 * Drain off all datagram fragments. 730 */ 731void 732ip_drain() 733{ 734 735 while (ipq.lh_first != NULL) { 736 ipstat.ips_fragdropped++; 737 ip_freef(ipq.lh_first); 738 } 739} 740 741/* 742 * Do option processing on a datagram, 743 * possibly discarding it if bad options are encountered, 744 * or forwarding it if source-routed. 745 * Returns 1 if packet has been forwarded/freed, 746 * 0 if the packet should be processed further. 747 */ 748int 749ip_dooptions(m) 750 struct mbuf *m; 751{ 752 register struct ip *ip = mtod(m, struct ip *); 753 register u_char *cp; 754 register struct ip_timestamp *ipt; 755 register struct in_ifaddr *ia; 756 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 757 struct in_addr *sin, dst; 758 n_time ntime; 759 760 dst = ip->ip_dst; 761 cp = (u_char *)(ip + 1); 762 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 763 for (; cnt > 0; cnt -= optlen, cp += optlen) { 764 opt = cp[IPOPT_OPTVAL]; 765 if (opt == IPOPT_EOL) 766 break; 767 if (opt == IPOPT_NOP) 768 optlen = 1; 769 else { 770 optlen = cp[IPOPT_OLEN]; 771 if (optlen <= 0 || optlen > cnt) { 772 code = &cp[IPOPT_OLEN] - (u_char *)ip; 773 goto bad; 774 } 775 } 776 switch (opt) { 777 778 default: 779 break; 780 781 /* 782 * Source routing with record. 783 * Find interface with current destination address. 784 * If none on this machine then drop if strictly routed, 785 * or do nothing if loosely routed. 786 * Record interface address and bring up next address 787 * component. If strictly routed make sure next 788 * address is on directly accessible net. 789 */ 790 case IPOPT_LSRR: 791 case IPOPT_SSRR: 792 if (ip_allowsrcrt == 0) { 793 type = ICMP_UNREACH; 794 code = ICMP_UNREACH_NET_PROHIB; 795 goto bad; 796 } 797 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 798 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 799 goto bad; 800 } 801 ipaddr.sin_addr = ip->ip_dst; 802 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 803 if (ia == 0) { 804 if (opt == IPOPT_SSRR) { 805 type = ICMP_UNREACH; 806 code = ICMP_UNREACH_SRCFAIL; 807 goto bad; 808 } 809 /* 810 * Loose routing, and not at next destination 811 * yet; nothing to do except forward. 812 */ 813 break; 814 } 815 off--; /* 0 origin */ 816 if (off > optlen - sizeof(struct in_addr)) { 817 /* 818 * End of source route. Should be for us. 819 */ 820 save_rte(cp, ip->ip_src); 821 break; 822 } 823 /* 824 * locate outgoing interface 825 */ 826 bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr, 827 sizeof(ipaddr.sin_addr)); 828 if (opt == IPOPT_SSRR) { 829#define INA struct in_ifaddr * 830#define SA struct sockaddr * 831 ia = (INA)ifa_ifwithladdr((SA)&ipaddr); 832 } else 833 ia = ip_rtaddr(ipaddr.sin_addr); 834 if (ia == 0) { 835 type = ICMP_UNREACH; 836 code = ICMP_UNREACH_SRCFAIL; 837 goto bad; 838 } 839 ip->ip_dst = ipaddr.sin_addr; 840 bcopy((caddr_t)&ia->ia_addr.sin_addr, 841 (caddr_t)(cp + off), sizeof(struct in_addr)); 842 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 843 /* 844 * Let ip_intr's mcast routing check handle mcast pkts 845 */ 846 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 847 break; 848 849 case IPOPT_RR: 850 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 851 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 852 goto bad; 853 } 854 /* 855 * If no space remains, ignore. 856 */ 857 off--; /* 0 origin */ 858 if (off > optlen - sizeof(struct in_addr)) 859 break; 860 bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr, 861 sizeof(ipaddr.sin_addr)); 862 /* 863 * locate outgoing interface; if we're the destination, 864 * use the incoming interface (should be same). 865 */ 866 if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0 && 867 (ia = ip_rtaddr(ipaddr.sin_addr)) == 0) { 868 type = ICMP_UNREACH; 869 code = ICMP_UNREACH_HOST; 870 goto bad; 871 } 872 bcopy((caddr_t)&ia->ia_addr.sin_addr, 873 (caddr_t)(cp + off), sizeof(struct in_addr)); 874 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 875 break; 876 877 case IPOPT_TS: 878 code = cp - (u_char *)ip; 879 ipt = (struct ip_timestamp *)cp; 880 if (ipt->ipt_len < 5) 881 goto bad; 882 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 883 if (++ipt->ipt_oflw == 0) 884 goto bad; 885 break; 886 } 887 sin = (struct in_addr *)(cp + ipt->ipt_ptr - 1); 888 switch (ipt->ipt_flg) { 889 890 case IPOPT_TS_TSONLY: 891 break; 892 893 case IPOPT_TS_TSANDADDR: 894 if (ipt->ipt_ptr + sizeof(n_time) + 895 sizeof(struct in_addr) > ipt->ipt_len) 896 goto bad; 897 ipaddr.sin_addr = dst; 898 ia = (INA)ifaof_ifpforaddr((SA)&ipaddr, 899 m->m_pkthdr.rcvif); 900 if (ia == 0) 901 continue; 902 bcopy((caddr_t)&ia->ia_addr.sin_addr, 903 (caddr_t)sin, sizeof(struct in_addr)); 904 ipt->ipt_ptr += sizeof(struct in_addr); 905 break; 906 907 case IPOPT_TS_PRESPEC: 908 if (ipt->ipt_ptr + sizeof(n_time) + 909 sizeof(struct in_addr) > ipt->ipt_len) 910 goto bad; 911 bcopy((caddr_t)sin, (caddr_t)&ipaddr.sin_addr, 912 sizeof(struct in_addr)); 913 if (ifa_ifwithaddr((SA)&ipaddr) == 0) 914 continue; 915 ipt->ipt_ptr += sizeof(struct in_addr); 916 break; 917 918 default: 919 goto bad; 920 } 921 ntime = iptime(); 922 bcopy((caddr_t)&ntime, (caddr_t)cp + ipt->ipt_ptr - 1, 923 sizeof(n_time)); 924 ipt->ipt_ptr += sizeof(n_time); 925 } 926 } 927 if (forward) { 928 if (ip_forwsrcrt == 0) { 929 type = ICMP_UNREACH; 930 code = ICMP_UNREACH_SRCFAIL; 931 goto bad; 932 } 933 ip_forward(m, 1); 934 return (1); 935 } 936 return (0); 937bad: 938 ip->ip_len -= ip->ip_hl << 2; /* XXX icmp_error adds in hdr length */ 939 icmp_error(m, type, code, 0, 0); 940 ipstat.ips_badoptions++; 941 return (1); 942} 943 944/* 945 * Given address of next destination (final or next hop), 946 * return internet address info of interface to be used to get there. 947 */ 948struct in_ifaddr * 949ip_rtaddr(dst) 950 struct in_addr dst; 951{ 952 register struct sockaddr_in *sin; 953 954 sin = satosin(&ipforward_rt.ro_dst); 955 956 if (ipforward_rt.ro_rt == 0 || !in_hosteq(dst, sin->sin_addr)) { 957 if (ipforward_rt.ro_rt) { 958 RTFREE(ipforward_rt.ro_rt); 959 ipforward_rt.ro_rt = 0; 960 } 961 sin->sin_family = AF_INET; 962 sin->sin_len = sizeof(*sin); 963 sin->sin_addr = dst; 964 965 rtalloc(&ipforward_rt); 966 } 967 if (ipforward_rt.ro_rt == 0) 968 return ((struct in_ifaddr *)0); 969 return (ifatoia(ipforward_rt.ro_rt->rt_ifa)); 970} 971 972/* 973 * Save incoming source route for use in replies, 974 * to be picked up later by ip_srcroute if the receiver is interested. 975 */ 976void 977save_rte(option, dst) 978 u_char *option; 979 struct in_addr dst; 980{ 981 unsigned olen; 982 983 olen = option[IPOPT_OLEN]; 984#ifdef DIAGNOSTIC 985 if (ipprintfs) 986 printf("save_rte: olen %d\n", olen); 987#endif 988 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 989 return; 990 bcopy((caddr_t)option, (caddr_t)ip_srcrt.srcopt, olen); 991 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 992 ip_srcrt.dst = dst; 993} 994 995/* 996 * Retrieve incoming source route for use in replies, 997 * in the same form used by setsockopt. 998 * The first hop is placed before the options, will be removed later. 999 */ 1000struct mbuf * 1001ip_srcroute() 1002{ 1003 register struct in_addr *p, *q; 1004 register struct mbuf *m; 1005 1006 if (ip_nhops == 0) 1007 return ((struct mbuf *)0); 1008 m = m_get(M_DONTWAIT, MT_SOOPTS); 1009 if (m == 0) 1010 return ((struct mbuf *)0); 1011 1012#define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1013 1014 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1015 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1016 OPTSIZ; 1017#ifdef DIAGNOSTIC 1018 if (ipprintfs) 1019 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1020#endif 1021 1022 /* 1023 * First save first hop for return route 1024 */ 1025 p = &ip_srcrt.route[ip_nhops - 1]; 1026 *(mtod(m, struct in_addr *)) = *p--; 1027#ifdef DIAGNOSTIC 1028 if (ipprintfs) 1029 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1030#endif 1031 1032 /* 1033 * Copy option fields and padding (nop) to mbuf. 1034 */ 1035 ip_srcrt.nop = IPOPT_NOP; 1036 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1037 bcopy((caddr_t)&ip_srcrt.nop, 1038 mtod(m, caddr_t) + sizeof(struct in_addr), OPTSIZ); 1039 q = (struct in_addr *)(mtod(m, caddr_t) + 1040 sizeof(struct in_addr) + OPTSIZ); 1041#undef OPTSIZ 1042 /* 1043 * Record return path as an IP source route, 1044 * reversing the path (pointers are now aligned). 1045 */ 1046 while (p >= ip_srcrt.route) { 1047#ifdef DIAGNOSTIC 1048 if (ipprintfs) 1049 printf(" %x", ntohl(q->s_addr)); 1050#endif 1051 *q++ = *p--; 1052 } 1053 /* 1054 * Last hop goes to final destination. 1055 */ 1056 *q = ip_srcrt.dst; 1057#ifdef DIAGNOSTIC 1058 if (ipprintfs) 1059 printf(" %x\n", ntohl(q->s_addr)); 1060#endif 1061 return (m); 1062} 1063 1064/* 1065 * Strip out IP options, at higher 1066 * level protocol in the kernel. 1067 * Second argument is buffer to which options 1068 * will be moved, and return value is their length. 1069 * XXX should be deleted; last arg currently ignored. 1070 */ 1071void 1072ip_stripoptions(m, mopt) 1073 register struct mbuf *m; 1074 struct mbuf *mopt; 1075{ 1076 register int i; 1077 struct ip *ip = mtod(m, struct ip *); 1078 register caddr_t opts; 1079 int olen; 1080 1081 olen = (ip->ip_hl<<2) - sizeof (struct ip); 1082 opts = (caddr_t)(ip + 1); 1083 i = m->m_len - (sizeof (struct ip) + olen); 1084 bcopy(opts + olen, opts, (unsigned)i); 1085 m->m_len -= olen; 1086 if (m->m_flags & M_PKTHDR) 1087 m->m_pkthdr.len -= olen; 1088 ip->ip_hl = sizeof(struct ip) >> 2; 1089} 1090 1091int inetctlerrmap[PRC_NCMDS] = { 1092 0, 0, 0, 0, 1093 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1094 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1095 EMSGSIZE, EHOSTUNREACH, 0, 0, 1096 0, 0, 0, 0, 1097 ENOPROTOOPT 1098}; 1099 1100/* 1101 * Forward a packet. If some error occurs return the sender 1102 * an icmp packet. Note we can't always generate a meaningful 1103 * icmp message because icmp doesn't have a large enough repertoire 1104 * of codes and types. 1105 * 1106 * If not forwarding, just drop the packet. This could be confusing 1107 * if ipforwarding was zero but some routing protocol was advancing 1108 * us as a gateway to somewhere. However, we must let the routing 1109 * protocol deal with that. 1110 * 1111 * The srcrt parameter indicates whether the packet is being forwarded 1112 * via a source route. 1113 */ 1114void 1115ip_forward(m, srcrt) 1116 struct mbuf *m; 1117 int srcrt; 1118{ 1119 register struct ip *ip = mtod(m, struct ip *); 1120 register struct sockaddr_in *sin; 1121 register struct rtentry *rt; 1122 int error, type = 0, code = 0; 1123 struct mbuf *mcopy; 1124 n_long dest; 1125 struct ifnet *destifp; 1126 1127 dest = 0; 1128#ifdef DIAGNOSTIC 1129 if (ipprintfs) 1130 printf("forward: src %x dst %x ttl %x\n", 1131 ip->ip_src.s_addr, ip->ip_dst.s_addr, ip->ip_ttl); 1132#endif 1133 if (m->m_flags & M_BCAST || in_canforward(ip->ip_dst) == 0) { 1134 ipstat.ips_cantforward++; 1135 m_freem(m); 1136 return; 1137 } 1138 HTONS(ip->ip_id); 1139 if (ip->ip_ttl <= IPTTLDEC) { 1140 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1141 return; 1142 } 1143 ip->ip_ttl -= IPTTLDEC; 1144 1145 sin = satosin(&ipforward_rt.ro_dst); 1146 if ((rt = ipforward_rt.ro_rt) == 0 || 1147 !in_hosteq(ip->ip_dst, sin->sin_addr)) { 1148 if (ipforward_rt.ro_rt) { 1149 RTFREE(ipforward_rt.ro_rt); 1150 ipforward_rt.ro_rt = 0; 1151 } 1152 sin->sin_family = AF_INET; 1153 sin->sin_len = sizeof(struct sockaddr_in); 1154 sin->sin_addr = ip->ip_dst; 1155 1156 rtalloc(&ipforward_rt); 1157 if (ipforward_rt.ro_rt == 0) { 1158 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0); 1159 return; 1160 } 1161 rt = ipforward_rt.ro_rt; 1162 } 1163 1164 /* 1165 * Save at most 68 bytes of the packet in case 1166 * we need to generate an ICMP message to the src. 1167 */ 1168 mcopy = m_copy(m, 0, imin((int)ip->ip_len, 68)); 1169 1170 /* 1171 * If forwarding packet using same interface that it came in on, 1172 * perhaps should send a redirect to sender to shortcut a hop. 1173 * Only send redirect if source is sending directly to us, 1174 * and if packet was not source routed (or has any options). 1175 * Also, don't send redirect if forwarding using a default route 1176 * or a route modified by a redirect. 1177 */ 1178 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1179 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1180 !in_nullhost(satosin(rt_key(rt))->sin_addr) && 1181 ipsendredirects && !srcrt) { 1182 if (rt->rt_ifa && 1183 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1184 ifatoia(rt->rt_ifa)->ia_subnet) { 1185 if (rt->rt_flags & RTF_GATEWAY) 1186 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1187 else 1188 dest = ip->ip_dst.s_addr; 1189 /* Router requirements says to only send host redirects */ 1190 type = ICMP_REDIRECT; 1191 code = ICMP_REDIRECT_HOST; 1192#ifdef DIAGNOSTIC 1193 if (ipprintfs) 1194 printf("redirect (%d) to %x\n", code, (u_int32_t)dest); 1195#endif 1196 } 1197 } 1198 1199 error = ip_output(m, (struct mbuf *)0, &ipforward_rt, 1200 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 0); 1201 if (error) 1202 ipstat.ips_cantforward++; 1203 else { 1204 ipstat.ips_forward++; 1205 if (type) 1206 ipstat.ips_redirectsent++; 1207 else { 1208 if (mcopy) { 1209#ifdef GATEWAY 1210 if (mcopy->m_flags & M_CANFASTFWD) 1211 ipflow_create(&ipforward_rt, mcopy); 1212#endif 1213 m_freem(mcopy); 1214 } 1215 return; 1216 } 1217 } 1218 if (mcopy == NULL) 1219 return; 1220 destifp = NULL; 1221 1222 switch (error) { 1223 1224 case 0: /* forwarded, but need redirect */ 1225 /* type, code set above */ 1226 break; 1227 1228 case ENETUNREACH: /* shouldn't happen, checked above */ 1229 case EHOSTUNREACH: 1230 case ENETDOWN: 1231 case EHOSTDOWN: 1232 default: 1233 type = ICMP_UNREACH; 1234 code = ICMP_UNREACH_HOST; 1235 break; 1236 1237 case EMSGSIZE: 1238 type = ICMP_UNREACH; 1239 code = ICMP_UNREACH_NEEDFRAG; 1240 if (ipforward_rt.ro_rt) 1241 destifp = ipforward_rt.ro_rt->rt_ifp; 1242 ipstat.ips_cantfrag++; 1243 break; 1244 1245 case ENOBUFS: 1246 type = ICMP_SOURCEQUENCH; 1247 code = 0; 1248 break; 1249 } 1250 icmp_error(mcopy, type, code, dest, destifp); 1251} 1252 1253void 1254ip_savecontrol(inp, mp, ip, m) 1255 register struct inpcb *inp; 1256 register struct mbuf **mp; 1257 register struct ip *ip; 1258 register struct mbuf *m; 1259{ 1260 1261 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 1262 struct timeval tv; 1263 1264 microtime(&tv); 1265 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1266 SCM_TIMESTAMP, SOL_SOCKET); 1267 if (*mp) 1268 mp = &(*mp)->m_next; 1269 } 1270 if (inp->inp_flags & INP_RECVDSTADDR) { 1271 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst, 1272 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 1273 if (*mp) 1274 mp = &(*mp)->m_next; 1275 } 1276#ifdef notyet 1277 /* 1278 * XXX 1279 * Moving these out of udp_input() made them even more broken 1280 * than they already were. 1281 * - fenner@parc.xerox.com 1282 */ 1283 /* options were tossed already */ 1284 if (inp->inp_flags & INP_RECVOPTS) { 1285 *mp = sbcreatecontrol((caddr_t) opts_deleted_above, 1286 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 1287 if (*mp) 1288 mp = &(*mp)->m_next; 1289 } 1290 /* ip_srcroute doesn't do what we want here, need to fix */ 1291 if (inp->inp_flags & INP_RECVRETOPTS) { 1292 *mp = sbcreatecontrol((caddr_t) ip_srcroute(), 1293 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 1294 if (*mp) 1295 mp = &(*mp)->m_next; 1296 } 1297#endif 1298 if (inp->inp_flags & INP_RECVIF) { 1299 struct sockaddr_dl sdl; 1300 1301 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]); 1302 sdl.sdl_family = AF_LINK; 1303 sdl.sdl_index = m->m_pkthdr.rcvif ? 1304 m->m_pkthdr.rcvif->if_index : 0; 1305 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0; 1306 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len, 1307 IP_RECVIF, IPPROTO_IP); 1308 if (*mp) 1309 mp = &(*mp)->m_next; 1310 } 1311} 1312 1313int 1314ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 1315 int *name; 1316 u_int namelen; 1317 void *oldp; 1318 size_t *oldlenp; 1319 void *newp; 1320 size_t newlen; 1321{ 1322 extern int subnetsarelocal; 1323 1324 int error, old; 1325 1326 /* All sysctl names at this level are terminal. */ 1327 if (namelen != 1) 1328 return (ENOTDIR); 1329 1330 switch (name[0]) { 1331 case IPCTL_FORWARDING: 1332 return (sysctl_int(oldp, oldlenp, newp, newlen, &ipforwarding)); 1333 case IPCTL_SENDREDIRECTS: 1334 return (sysctl_int(oldp, oldlenp, newp, newlen, 1335 &ipsendredirects)); 1336 case IPCTL_DEFTTL: 1337 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_defttl)); 1338#ifdef notyet 1339 case IPCTL_DEFMTU: 1340 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu)); 1341#endif 1342 case IPCTL_FORWSRCRT: 1343 /* Don't allow this to change in a secure environment. */ 1344 if (securelevel > 0) 1345 return (sysctl_rdint(oldp, oldlenp, newp, 1346 ip_forwsrcrt)); 1347 else 1348 return (sysctl_int(oldp, oldlenp, newp, newlen, 1349 &ip_forwsrcrt)); 1350 case IPCTL_DIRECTEDBCAST: 1351 return (sysctl_int(oldp, oldlenp, newp, newlen, 1352 &ip_directedbcast)); 1353 case IPCTL_ALLOWSRCRT: 1354 return (sysctl_int(oldp, oldlenp, newp, newlen, 1355 &ip_allowsrcrt)); 1356 case IPCTL_SUBNETSARELOCAL: 1357 return (sysctl_int(oldp, oldlenp, newp, newlen, 1358 &subnetsarelocal)); 1359 case IPCTL_MTUDISC: 1360 error = sysctl_int(oldp, oldlenp, newp, newlen, 1361 &ip_mtudisc); 1362 if (ip_mtudisc != 0 && ip_mtudisc_timeout_q == NULL) { 1363 ip_mtudisc_timeout_q = 1364 rt_timer_queue_create(ip_mtudisc_timeout); 1365 } else if (ip_mtudisc == 0 && ip_mtudisc_timeout_q != NULL) { 1366 rt_timer_queue_destroy(ip_mtudisc_timeout_q, TRUE); 1367 ip_mtudisc_timeout_q = NULL; 1368 } 1369 return error; 1370 case IPCTL_ANONPORTMIN: 1371 old = anonportmin; 1372 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmin); 1373 if (anonportmin >= anonportmax || anonportmin > 65535 1374#ifndef IPNOPRIVPORTS 1375 || anonportmin < IPPORT_RESERVED 1376#endif 1377 ) { 1378 anonportmin = old; 1379 return (EINVAL); 1380 } 1381 return (error); 1382 case IPCTL_ANONPORTMAX: 1383 old = anonportmax; 1384 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmax); 1385 if (anonportmin >= anonportmax || anonportmax > 65535 1386#ifndef IPNOPRIVPORTS 1387 || anonportmax < IPPORT_RESERVED 1388#endif 1389 ) { 1390 anonportmax = old; 1391 return (EINVAL); 1392 } 1393 return (error); 1394 case IPCTL_MTUDISCTIMEOUT: 1395 error = sysctl_int(oldp, oldlenp, newp, newlen, 1396 &ip_mtudisc_timeout); 1397 if (ip_mtudisc_timeout_q != NULL) 1398 rt_timer_queue_change(ip_mtudisc_timeout_q, 1399 ip_mtudisc_timeout); 1400 return (error); 1401 default: 1402 return (EOPNOTSUPP); 1403 } 1404 /* NOTREACHED */ 1405} 1406