1 /* $NetBSD: ip_input.c,v 1.74 1998/11/13 03:24:22 thorpej Exp $ */ 2 3 /* 4 * Copyright (c) 1982, 1986, 1988, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by the University of 18 * California, Berkeley and its contributors. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 36 */ 37 38 /*- 39 * Copyright (c) 1998 The NetBSD Foundation, Inc. 40 * All rights reserved. 41 * 42 * This code is derived from software contributed to The NetBSD Foundation 43 * by Public Access Networks Corporation ("Panix"). It was developed under 44 * contract to Panix by Eric Haszlakiewicz and Thor Lancelot Simon. 45 * 46 * Redistribution and use in source and binary forms, with or without 47 * modification, are permitted provided that the following conditions 48 * are met: 49 * 1. Redistributions of source code must retain the above copyright 50 * notice, this list of conditions and the following disclaimer. 51 * 2. Redistributions in binary form must reproduce the above copyright 52 * notice, this list of conditions and the following disclaimer in the 53 * documentation and/or other materials provided with the distribution. 54 * 3. All advertising materials mentioning features or use of this software 55 * must display the following acknowledgement: 56 * This product includes software developed by the NetBSD 57 * Foundation, Inc. and its contributors. 58 * 4. Neither the name of The NetBSD Foundation nor the names of its 59 * contributors may be used to endorse or promote products derived 60 * from this software without specific prior written permission. 61 * 62 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 63 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 64 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 65 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 66 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 67 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 68 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 69 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 70 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 71 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 72 * POSSIBILITY OF SUCH DAMAGE. 73 */ 74 75 #include "opt_gateway.h" 76 #include "opt_pfil_hooks.h" 77 #include "opt_mrouting.h" 78 79 #include <sys/param.h> 80 #include <sys/systm.h> 81 #include <sys/malloc.h> 82 #include <sys/mbuf.h> 83 #include <sys/domain.h> 84 #include <sys/protosw.h> 85 #include <sys/socket.h> 86 #include <sys/socketvar.h> 87 #include <sys/errno.h> 88 #include <sys/time.h> 89 #include <sys/kernel.h> 90 #include <sys/proc.h> 91 #include <sys/pool.h> 92 93 #include <vm/vm.h> 94 #include <sys/sysctl.h> 95 96 #include <net/if.h> 97 #include <net/if_dl.h> 98 #include <net/route.h> 99 #include <net/pfil.h> 100 101 #include <netinet/in.h> 102 #include <netinet/in_systm.h> 103 #include <netinet/ip.h> 104 #include <netinet/in_pcb.h> 105 #include <netinet/in_var.h> 106 #include <netinet/ip_var.h> 107 #include <netinet/ip_icmp.h> 108 109 #ifndef IPFORWARDING 110 #ifdef GATEWAY 111 #define IPFORWARDING 1 /* forward IP packets not for us */ 112 #else /* GATEWAY */ 113 #define IPFORWARDING 0 /* don't forward IP packets not for us */ 114 #endif /* GATEWAY */ 115 #endif /* IPFORWARDING */ 116 #ifndef IPSENDREDIRECTS 117 #define IPSENDREDIRECTS 1 118 #endif 119 #ifndef IPFORWSRCRT 120 #define IPFORWSRCRT 1 /* forward source-routed packets */ 121 #endif 122 #ifndef IPALLOWSRCRT 123 #define IPALLOWSRCRT 1 /* allow source-routed packets */ 124 #endif 125 #ifndef IPMTUDISC 126 #define IPMTUDISC 0 127 #endif 128 #ifndef IPMTUDISCTIMEOUT 129 #define IPMTUDISCTIMEOUT (10 * 60) /* as per RFC 1191 */ 130 #endif 131 132 /* 133 * Note: DIRECTED_BROADCAST is handled this way so that previous 134 * configuration using this option will Just Work. 135 */ 136 #ifndef IPDIRECTEDBCAST 137 #ifdef DIRECTED_BROADCAST 138 #define IPDIRECTEDBCAST 1 139 #else 140 #define IPDIRECTEDBCAST 0 141 #endif /* DIRECTED_BROADCAST */ 142 #endif /* IPDIRECTEDBCAST */ 143 int ipforwarding = IPFORWARDING; 144 int ipsendredirects = IPSENDREDIRECTS; 145 int ip_defttl = IPDEFTTL; 146 int ip_forwsrcrt = IPFORWSRCRT; 147 int ip_directedbcast = IPDIRECTEDBCAST; 148 int ip_allowsrcrt = IPALLOWSRCRT; 149 int ip_mtudisc = IPMTUDISC; 150 u_int ip_mtudisc_timeout = IPMTUDISCTIMEOUT; 151 #ifdef DIAGNOSTIC 152 int ipprintfs = 0; 153 #endif 154 155 struct rttimer_queue *ip_mtudisc_timeout_q = NULL; 156 157 extern struct domain inetdomain; 158 extern struct protosw inetsw[]; 159 u_char ip_protox[IPPROTO_MAX]; 160 int ipqmaxlen = IFQ_MAXLEN; 161 struct in_ifaddrhead in_ifaddr; 162 struct in_ifaddrhashhead *in_ifaddrhashtbl; 163 struct ifqueue ipintrq; 164 struct ipstat ipstat; 165 u_int16_t ip_id; 166 int ip_defttl; 167 struct ipqhead ipq; 168 169 struct pool ipqent_pool; 170 171 /* 172 * We need to save the IP options in case a protocol wants to respond 173 * to an incoming packet over the same route if the packet got here 174 * using IP source routing. This allows connection establishment and 175 * maintenance when the remote end is on a network that is not known 176 * to us. 177 */ 178 int ip_nhops = 0; 179 static struct ip_srcrt { 180 struct in_addr dst; /* final destination */ 181 char nop; /* one NOP to align */ 182 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */ 183 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)]; 184 } ip_srcrt; 185 186 static void save_rte __P((u_char *, struct in_addr)); 187 188 /* 189 * IP initialization: fill in IP protocol switch table. 190 * All protocols not implemented in kernel go to raw IP protocol handler. 191 */ 192 void 193 ip_init() 194 { 195 register struct protosw *pr; 196 register int i; 197 198 pool_init(&ipqent_pool, sizeof(struct ipqent), 0, 0, 0, "ipqepl", 199 0, NULL, NULL, M_IPQ); 200 201 pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); 202 if (pr == 0) 203 panic("ip_init"); 204 for (i = 0; i < IPPROTO_MAX; i++) 205 ip_protox[i] = pr - inetsw; 206 for (pr = inetdomain.dom_protosw; 207 pr < inetdomain.dom_protoswNPROTOSW; pr++) 208 if (pr->pr_domain->dom_family == PF_INET && 209 pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) 210 ip_protox[pr->pr_protocol] = pr - inetsw; 211 LIST_INIT(&ipq); 212 ip_id = time.tv_sec & 0xffff; 213 ipintrq.ifq_maxlen = ipqmaxlen; 214 TAILQ_INIT(&in_ifaddr); 215 in_ifaddrhashtbl = 216 hashinit(IN_IFADDR_HASH_SIZE, M_IFADDR, M_WAITOK, &in_ifaddrhash); 217 if (ip_mtudisc != 0) 218 ip_mtudisc_timeout_q = 219 rt_timer_queue_create(ip_mtudisc_timeout); 220 #ifdef GATEWAY 221 ipflow_init(); 222 #endif 223 } 224 225 struct sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET }; 226 struct route ipforward_rt; 227 228 /* 229 * Ip input routine. Checksum and byte swap header. If fragmented 230 * try to reassemble. Process options. Pass to next level. 231 */ 232 void 233 ipintr() 234 { 235 register struct ip *ip = NULL; 236 register struct mbuf *m; 237 register struct ipq *fp; 238 register struct in_ifaddr *ia; 239 register struct ifaddr *ifa; 240 struct ipqent *ipqe; 241 int hlen = 0, mff, len, s; 242 #ifdef PFIL_HOOKS 243 struct packet_filter_hook *pfh; 244 struct mbuf *m0; 245 int rv; 246 #endif /* PFIL_HOOKS */ 247 248 next: 249 /* 250 * Get next datagram off input queue and get IP header 251 * in first mbuf. 252 */ 253 s = splimp(); 254 IF_DEQUEUE(&ipintrq, m); 255 splx(s); 256 if (m == 0) 257 return; 258 #ifdef DIAGNOSTIC 259 if ((m->m_flags & M_PKTHDR) == 0) 260 panic("ipintr no HDR"); 261 #endif 262 /* 263 * If no IP addresses have been set yet but the interfaces 264 * are receiving, can't do anything with incoming packets yet. 265 */ 266 if (in_ifaddr.tqh_first == 0) 267 goto bad; 268 ipstat.ips_total++; 269 if (m->m_len < sizeof (struct ip) && 270 (m = m_pullup(m, sizeof (struct ip))) == 0) { 271 ipstat.ips_toosmall++; 272 goto next; 273 } 274 ip = mtod(m, struct ip *); 275 if (ip->ip_v != IPVERSION) { 276 ipstat.ips_badvers++; 277 goto bad; 278 } 279 hlen = ip->ip_hl << 2; 280 if (hlen < sizeof(struct ip)) { /* minimum header length */ 281 ipstat.ips_badhlen++; 282 goto bad; 283 } 284 if (hlen > m->m_len) { 285 if ((m = m_pullup(m, hlen)) == 0) { 286 ipstat.ips_badhlen++; 287 goto next; 288 } 289 ip = mtod(m, struct ip *); 290 } 291 if ((ip->ip_sum = in_cksum(m, hlen)) != 0) { 292 ipstat.ips_badsum++; 293 goto bad; 294 } 295 296 /* 297 * Convert fields to host representation. 298 */ 299 NTOHS(ip->ip_len); 300 NTOHS(ip->ip_id); 301 NTOHS(ip->ip_off); 302 len = ip->ip_len; 303 304 /* 305 * Check that the amount of data in the buffers 306 * is as at least much as the IP header would have us expect. 307 * Trim mbufs if longer than we expect. 308 * Drop packet if shorter than we expect. 309 */ 310 if (m->m_pkthdr.len < len) { 311 ipstat.ips_tooshort++; 312 goto bad; 313 } 314 if (m->m_pkthdr.len > len) { 315 if (m->m_len == m->m_pkthdr.len) { 316 m->m_len = len; 317 m->m_pkthdr.len = len; 318 } else 319 m_adj(m, len - m->m_pkthdr.len); 320 } 321 322 /* 323 * Assume that we can create a fast-forward IP flow entry 324 * based on this packet. 325 */ 326 m->m_flags |= M_CANFASTFWD; 327 328 #ifdef PFIL_HOOKS 329 /* 330 * Run through list of hooks for input packets. If there are any 331 * filters which require that additional packets in the flow are 332 * not fast-forwarded, they must clear the M_CANFASTFWD flag. 333 * Note that filters must _never_ set this flag, as another filter 334 * in the list may have previously cleared it. 335 */ 336 m0 = m; 337 for (pfh = pfil_hook_get(PFIL_IN); pfh; pfh = pfh->pfil_link.tqe_next) 338 if (pfh->pfil_func) { 339 rv = pfh->pfil_func(ip, hlen, m->m_pkthdr.rcvif, 0, &m0); 340 if (rv) 341 goto next; 342 m = m0; 343 if (m == NULL) 344 goto next; 345 ip = mtod(m, struct ip *); 346 } 347 #endif /* PFIL_HOOKS */ 348 349 /* 350 * Process options and, if not destined for us, 351 * ship it on. ip_dooptions returns 1 when an 352 * error was detected (causing an icmp message 353 * to be sent and the original packet to be freed). 354 */ 355 ip_nhops = 0; /* for source routed packets */ 356 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 357 goto next; 358 359 /* 360 * Check our list of addresses, to see if the packet is for us. 361 */ 362 INADDR_TO_IA(ip->ip_dst, ia); 363 if (ia != NULL) goto ours; 364 if (m->m_pkthdr.rcvif->if_flags & IFF_BROADCAST) { 365 for (ifa = m->m_pkthdr.rcvif->if_addrlist.tqh_first; 366 ifa != NULL; ifa = ifa->ifa_list.tqe_next) { 367 if (ifa->ifa_addr->sa_family != AF_INET) continue; 368 ia = ifatoia(ifa); 369 if (in_hosteq(ip->ip_dst, ia->ia_broadaddr.sin_addr) || 370 in_hosteq(ip->ip_dst, ia->ia_netbroadcast) || 371 /* 372 * Look for all-0's host part (old broadcast addr), 373 * either for subnet or net. 374 */ 375 ip->ip_dst.s_addr == ia->ia_subnet || 376 ip->ip_dst.s_addr == ia->ia_net) 377 goto ours; 378 /* 379 * An interface with IP address zero accepts 380 * all packets that arrive on that interface. 381 */ 382 if (in_nullhost(ia->ia_addr.sin_addr)) 383 goto ours; 384 } 385 } 386 if (IN_MULTICAST(ip->ip_dst.s_addr)) { 387 struct in_multi *inm; 388 #ifdef MROUTING 389 extern struct socket *ip_mrouter; 390 391 if (m->m_flags & M_EXT) { 392 if ((m = m_pullup(m, hlen)) == 0) { 393 ipstat.ips_toosmall++; 394 goto next; 395 } 396 ip = mtod(m, struct ip *); 397 } 398 399 if (ip_mrouter) { 400 /* 401 * If we are acting as a multicast router, all 402 * incoming multicast packets are passed to the 403 * kernel-level multicast forwarding function. 404 * The packet is returned (relatively) intact; if 405 * ip_mforward() returns a non-zero value, the packet 406 * must be discarded, else it may be accepted below. 407 * 408 * (The IP ident field is put in the same byte order 409 * as expected when ip_mforward() is called from 410 * ip_output().) 411 */ 412 ip->ip_id = htons(ip->ip_id); 413 if (ip_mforward(m, m->m_pkthdr.rcvif) != 0) { 414 ipstat.ips_cantforward++; 415 m_freem(m); 416 goto next; 417 } 418 ip->ip_id = ntohs(ip->ip_id); 419 420 /* 421 * The process-level routing demon needs to receive 422 * all multicast IGMP packets, whether or not this 423 * host belongs to their destination groups. 424 */ 425 if (ip->ip_p == IPPROTO_IGMP) 426 goto ours; 427 ipstat.ips_forward++; 428 } 429 #endif 430 /* 431 * See if we belong to the destination multicast group on the 432 * arrival interface. 433 */ 434 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 435 if (inm == NULL) { 436 ipstat.ips_cantforward++; 437 m_freem(m); 438 goto next; 439 } 440 goto ours; 441 } 442 if (ip->ip_dst.s_addr == INADDR_BROADCAST || 443 in_nullhost(ip->ip_dst)) 444 goto ours; 445 446 /* 447 * Not for us; forward if possible and desirable. 448 */ 449 if (ipforwarding == 0) { 450 ipstat.ips_cantforward++; 451 m_freem(m); 452 } else 453 ip_forward(m, 0); 454 goto next; 455 456 ours: 457 /* 458 * If offset or IP_MF are set, must reassemble. 459 * Otherwise, nothing need be done. 460 * (We could look in the reassembly queue to see 461 * if the packet was previously fragmented, 462 * but it's not worth the time; just let them time out.) 463 */ 464 if (ip->ip_off & ~(IP_DF|IP_RF)) { 465 /* 466 * Look for queue of fragments 467 * of this datagram. 468 */ 469 for (fp = ipq.lh_first; fp != NULL; fp = fp->ipq_q.le_next) 470 if (ip->ip_id == fp->ipq_id && 471 in_hosteq(ip->ip_src, fp->ipq_src) && 472 in_hosteq(ip->ip_dst, fp->ipq_dst) && 473 ip->ip_p == fp->ipq_p) 474 goto found; 475 fp = 0; 476 found: 477 478 /* 479 * Adjust ip_len to not reflect header, 480 * set ipqe_mff if more fragments are expected, 481 * convert offset of this to bytes. 482 */ 483 ip->ip_len -= hlen; 484 mff = (ip->ip_off & IP_MF) != 0; 485 if (mff) { 486 /* 487 * Make sure that fragments have a data length 488 * that's a non-zero multiple of 8 bytes. 489 */ 490 if (ip->ip_len == 0 || (ip->ip_len & 0x7) != 0) { 491 ipstat.ips_badfrags++; 492 goto bad; 493 } 494 } 495 ip->ip_off <<= 3; 496 497 /* 498 * If datagram marked as having more fragments 499 * or if this is not the first fragment, 500 * attempt reassembly; if it succeeds, proceed. 501 */ 502 if (mff || ip->ip_off) { 503 ipstat.ips_fragments++; 504 ipqe = pool_get(&ipqent_pool, PR_NOWAIT); 505 if (ipqe == NULL) { 506 ipstat.ips_rcvmemdrop++; 507 goto bad; 508 } 509 ipqe->ipqe_mff = mff; 510 ipqe->ipqe_m = m; 511 ipqe->ipqe_ip = ip; 512 m = ip_reass(ipqe, fp); 513 if (m == 0) 514 goto next; 515 ipstat.ips_reassembled++; 516 ip = mtod(m, struct ip *); 517 hlen = ip->ip_hl << 2; 518 } else 519 if (fp) 520 ip_freef(fp); 521 } else 522 ip->ip_len -= hlen; 523 524 /* 525 * Switch out to protocol's input routine. 526 */ 527 ipstat.ips_delivered++; 528 (*inetsw[ip_protox[ip->ip_p]].pr_input)(m, hlen); 529 goto next; 530 bad: 531 m_freem(m); 532 goto next; 533 } 534 535 /* 536 * Take incoming datagram fragment and try to 537 * reassemble it into whole datagram. If a chain for 538 * reassembly of this datagram already exists, then it 539 * is given as fp; otherwise have to make a chain. 540 */ 541 struct mbuf * 542 ip_reass(ipqe, fp) 543 register struct ipqent *ipqe; 544 register struct ipq *fp; 545 { 546 register struct mbuf *m = ipqe->ipqe_m; 547 register struct ipqent *nq, *p, *q; 548 struct ip *ip; 549 struct mbuf *t; 550 int hlen = ipqe->ipqe_ip->ip_hl << 2; 551 int i, next; 552 553 /* 554 * Presence of header sizes in mbufs 555 * would confuse code below. 556 */ 557 m->m_data += hlen; 558 m->m_len -= hlen; 559 560 /* 561 * If first fragment to arrive, create a reassembly queue. 562 */ 563 if (fp == 0) { 564 MALLOC(fp, struct ipq *, sizeof (struct ipq), 565 M_FTABLE, M_NOWAIT); 566 if (fp == NULL) 567 goto dropfrag; 568 LIST_INSERT_HEAD(&ipq, fp, ipq_q); 569 fp->ipq_ttl = IPFRAGTTL; 570 fp->ipq_p = ipqe->ipqe_ip->ip_p; 571 fp->ipq_id = ipqe->ipqe_ip->ip_id; 572 LIST_INIT(&fp->ipq_fragq); 573 fp->ipq_src = ipqe->ipqe_ip->ip_src; 574 fp->ipq_dst = ipqe->ipqe_ip->ip_dst; 575 p = NULL; 576 goto insert; 577 } 578 579 /* 580 * Find a segment which begins after this one does. 581 */ 582 for (p = NULL, q = fp->ipq_fragq.lh_first; q != NULL; 583 p = q, q = q->ipqe_q.le_next) 584 if (q->ipqe_ip->ip_off > ipqe->ipqe_ip->ip_off) 585 break; 586 587 /* 588 * If there is a preceding segment, it may provide some of 589 * our data already. If so, drop the data from the incoming 590 * segment. If it provides all of our data, drop us. 591 */ 592 if (p != NULL) { 593 i = p->ipqe_ip->ip_off + p->ipqe_ip->ip_len - 594 ipqe->ipqe_ip->ip_off; 595 if (i > 0) { 596 if (i >= ipqe->ipqe_ip->ip_len) 597 goto dropfrag; 598 m_adj(ipqe->ipqe_m, i); 599 ipqe->ipqe_ip->ip_off += i; 600 ipqe->ipqe_ip->ip_len -= i; 601 } 602 } 603 604 /* 605 * While we overlap succeeding segments trim them or, 606 * if they are completely covered, dequeue them. 607 */ 608 for (; q != NULL && ipqe->ipqe_ip->ip_off + ipqe->ipqe_ip->ip_len > 609 q->ipqe_ip->ip_off; q = nq) { 610 i = (ipqe->ipqe_ip->ip_off + ipqe->ipqe_ip->ip_len) - 611 q->ipqe_ip->ip_off; 612 if (i < q->ipqe_ip->ip_len) { 613 q->ipqe_ip->ip_len -= i; 614 q->ipqe_ip->ip_off += i; 615 m_adj(q->ipqe_m, i); 616 break; 617 } 618 nq = q->ipqe_q.le_next; 619 m_freem(q->ipqe_m); 620 LIST_REMOVE(q, ipqe_q); 621 pool_put(&ipqent_pool, q); 622 } 623 624 insert: 625 /* 626 * Stick new segment in its place; 627 * check for complete reassembly. 628 */ 629 if (p == NULL) { 630 LIST_INSERT_HEAD(&fp->ipq_fragq, ipqe, ipqe_q); 631 } else { 632 LIST_INSERT_AFTER(p, ipqe, ipqe_q); 633 } 634 next = 0; 635 for (p = NULL, q = fp->ipq_fragq.lh_first; q != NULL; 636 p = q, q = q->ipqe_q.le_next) { 637 if (q->ipqe_ip->ip_off != next) 638 return (0); 639 next += q->ipqe_ip->ip_len; 640 } 641 if (p->ipqe_mff) 642 return (0); 643 644 /* 645 * Reassembly is complete. Check for a bogus message size and 646 * concatenate fragments. 647 */ 648 q = fp->ipq_fragq.lh_first; 649 ip = q->ipqe_ip; 650 if ((next + (ip->ip_hl << 2)) > IP_MAXPACKET) { 651 ipstat.ips_toolong++; 652 ip_freef(fp); 653 return (0); 654 } 655 m = q->ipqe_m; 656 t = m->m_next; 657 m->m_next = 0; 658 m_cat(m, t); 659 nq = q->ipqe_q.le_next; 660 pool_put(&ipqent_pool, q); 661 for (q = nq; q != NULL; q = nq) { 662 t = q->ipqe_m; 663 nq = q->ipqe_q.le_next; 664 pool_put(&ipqent_pool, q); 665 m_cat(m, t); 666 } 667 668 /* 669 * Create header for new ip packet by 670 * modifying header of first packet; 671 * dequeue and discard fragment reassembly header. 672 * Make header visible. 673 */ 674 ip->ip_len = next; 675 ip->ip_src = fp->ipq_src; 676 ip->ip_dst = fp->ipq_dst; 677 LIST_REMOVE(fp, ipq_q); 678 FREE(fp, M_FTABLE); 679 m->m_len += (ip->ip_hl << 2); 680 m->m_data -= (ip->ip_hl << 2); 681 /* some debugging cruft by sklower, below, will go away soon */ 682 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 683 register int plen = 0; 684 for (t = m; t; t = t->m_next) 685 plen += t->m_len; 686 m->m_pkthdr.len = plen; 687 } 688 return (m); 689 690 dropfrag: 691 ipstat.ips_fragdropped++; 692 m_freem(m); 693 pool_put(&ipqent_pool, ipqe); 694 return (0); 695 } 696 697 /* 698 * Free a fragment reassembly header and all 699 * associated datagrams. 700 */ 701 void 702 ip_freef(fp) 703 struct ipq *fp; 704 { 705 register struct ipqent *q, *p; 706 707 for (q = fp->ipq_fragq.lh_first; q != NULL; q = p) { 708 p = q->ipqe_q.le_next; 709 m_freem(q->ipqe_m); 710 LIST_REMOVE(q, ipqe_q); 711 pool_put(&ipqent_pool, q); 712 } 713 LIST_REMOVE(fp, ipq_q); 714 FREE(fp, M_FTABLE); 715 } 716 717 /* 718 * IP timer processing; 719 * if a timer expires on a reassembly 720 * queue, discard it. 721 */ 722 void 723 ip_slowtimo() 724 { 725 register struct ipq *fp, *nfp; 726 int s = splsoftnet(); 727 728 for (fp = ipq.lh_first; fp != NULL; fp = nfp) { 729 nfp = fp->ipq_q.le_next; 730 if (--fp->ipq_ttl == 0) { 731 ipstat.ips_fragtimeout++; 732 ip_freef(fp); 733 } 734 } 735 #ifdef GATEWAY 736 ipflow_slowtimo(); 737 #endif 738 splx(s); 739 } 740 741 /* 742 * Drain off all datagram fragments. 743 */ 744 void 745 ip_drain() 746 { 747 748 while (ipq.lh_first != NULL) { 749 ipstat.ips_fragdropped++; 750 ip_freef(ipq.lh_first); 751 } 752 } 753 754 /* 755 * Do option processing on a datagram, 756 * possibly discarding it if bad options are encountered, 757 * or forwarding it if source-routed. 758 * Returns 1 if packet has been forwarded/freed, 759 * 0 if the packet should be processed further. 760 */ 761 int 762 ip_dooptions(m) 763 struct mbuf *m; 764 { 765 register struct ip *ip = mtod(m, struct ip *); 766 register u_char *cp; 767 register struct ip_timestamp *ipt; 768 register struct in_ifaddr *ia; 769 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 770 struct in_addr *sin, dst; 771 n_time ntime; 772 773 dst = ip->ip_dst; 774 cp = (u_char *)(ip + 1); 775 cnt = (ip->ip_hl << 2) - sizeof (struct ip); 776 for (; cnt > 0; cnt -= optlen, cp += optlen) { 777 opt = cp[IPOPT_OPTVAL]; 778 if (opt == IPOPT_EOL) 779 break; 780 if (opt == IPOPT_NOP) 781 optlen = 1; 782 else { 783 optlen = cp[IPOPT_OLEN]; 784 if (optlen <= 0 || optlen > cnt) { 785 code = &cp[IPOPT_OLEN] - (u_char *)ip; 786 goto bad; 787 } 788 } 789 switch (opt) { 790 791 default: 792 break; 793 794 /* 795 * Source routing with record. 796 * Find interface with current destination address. 797 * If none on this machine then drop if strictly routed, 798 * or do nothing if loosely routed. 799 * Record interface address and bring up next address 800 * component. If strictly routed make sure next 801 * address is on directly accessible net. 802 */ 803 case IPOPT_LSRR: 804 case IPOPT_SSRR: 805 if (ip_allowsrcrt == 0) { 806 type = ICMP_UNREACH; 807 code = ICMP_UNREACH_NET_PROHIB; 808 goto bad; 809 } 810 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 811 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 812 goto bad; 813 } 814 ipaddr.sin_addr = ip->ip_dst; 815 ia = ifatoia(ifa_ifwithaddr(sintosa(&ipaddr))); 816 if (ia == 0) { 817 if (opt == IPOPT_SSRR) { 818 type = ICMP_UNREACH; 819 code = ICMP_UNREACH_SRCFAIL; 820 goto bad; 821 } 822 /* 823 * Loose routing, and not at next destination 824 * yet; nothing to do except forward. 825 */ 826 break; 827 } 828 off--; /* 0 origin */ 829 if (off > optlen - sizeof(struct in_addr)) { 830 /* 831 * End of source route. Should be for us. 832 */ 833 save_rte(cp, ip->ip_src); 834 break; 835 } 836 /* 837 * locate outgoing interface 838 */ 839 bcopy((caddr_t)(cp + off), (caddr_t)&ipaddr.sin_addr, 840 sizeof(ipaddr.sin_addr)); 841 if (opt == IPOPT_SSRR) { 842 #define INA struct in_ifaddr * 843 #define SA struct sockaddr * 844 ia = (INA)ifa_ifwithladdr((SA)&ipaddr); 845 } else 846 ia = ip_rtaddr(ipaddr.sin_addr); 847 if (ia == 0) { 848 type = ICMP_UNREACH; 849 code = ICMP_UNREACH_SRCFAIL; 850 goto bad; 851 } 852 ip->ip_dst = ipaddr.sin_addr; 853 bcopy((caddr_t)&ia->ia_addr.sin_addr, 854 (caddr_t)(cp + off), sizeof(struct in_addr)); 855 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 856 /* 857 * Let ip_intr's mcast routing check handle mcast pkts 858 */ 859 forward = !IN_MULTICAST(ip->ip_dst.s_addr); 860 break; 861 862 case IPOPT_RR: 863 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 864 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 865 goto bad; 866 } 867 /* 868 * If no space remains, ignore. 869 */ 870 off--; /* 0 origin */ 871 if (off > optlen - sizeof(struct in_addr)) 872 break; 873 bcopy((caddr_t)(&ip->ip_dst), (caddr_t)&ipaddr.sin_addr, 874 sizeof(ipaddr.sin_addr)); 875 /* 876 * locate outgoing interface; if we're the destination, 877 * use the incoming interface (should be same). 878 */ 879 if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0 && 880 (ia = ip_rtaddr(ipaddr.sin_addr)) == 0) { 881 type = ICMP_UNREACH; 882 code = ICMP_UNREACH_HOST; 883 goto bad; 884 } 885 bcopy((caddr_t)&ia->ia_addr.sin_addr, 886 (caddr_t)(cp + off), sizeof(struct in_addr)); 887 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 888 break; 889 890 case IPOPT_TS: 891 code = cp - (u_char *)ip; 892 ipt = (struct ip_timestamp *)cp; 893 if (ipt->ipt_len < 5) 894 goto bad; 895 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (int32_t)) { 896 if (++ipt->ipt_oflw == 0) 897 goto bad; 898 break; 899 } 900 sin = (struct in_addr *)(cp + ipt->ipt_ptr - 1); 901 switch (ipt->ipt_flg) { 902 903 case IPOPT_TS_TSONLY: 904 break; 905 906 case IPOPT_TS_TSANDADDR: 907 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 908 sizeof(struct in_addr) > ipt->ipt_len) 909 goto bad; 910 ipaddr.sin_addr = dst; 911 ia = (INA)ifaof_ifpforaddr((SA)&ipaddr, 912 m->m_pkthdr.rcvif); 913 if (ia == 0) 914 continue; 915 bcopy((caddr_t)&ia->ia_addr.sin_addr, 916 (caddr_t)sin, sizeof(struct in_addr)); 917 ipt->ipt_ptr += sizeof(struct in_addr); 918 break; 919 920 case IPOPT_TS_PRESPEC: 921 if (ipt->ipt_ptr - 1 + sizeof(n_time) + 922 sizeof(struct in_addr) > ipt->ipt_len) 923 goto bad; 924 bcopy((caddr_t)sin, (caddr_t)&ipaddr.sin_addr, 925 sizeof(struct in_addr)); 926 if (ifa_ifwithaddr((SA)&ipaddr) == 0) 927 continue; 928 ipt->ipt_ptr += sizeof(struct in_addr); 929 break; 930 931 default: 932 goto bad; 933 } 934 ntime = iptime(); 935 bcopy((caddr_t)&ntime, (caddr_t)cp + ipt->ipt_ptr - 1, 936 sizeof(n_time)); 937 ipt->ipt_ptr += sizeof(n_time); 938 } 939 } 940 if (forward) { 941 if (ip_forwsrcrt == 0) { 942 type = ICMP_UNREACH; 943 code = ICMP_UNREACH_SRCFAIL; 944 goto bad; 945 } 946 ip_forward(m, 1); 947 return (1); 948 } 949 return (0); 950 bad: 951 ip->ip_len -= ip->ip_hl << 2; /* XXX icmp_error adds in hdr length */ 952 icmp_error(m, type, code, 0, 0); 953 ipstat.ips_badoptions++; 954 return (1); 955 } 956 957 /* 958 * Given address of next destination (final or next hop), 959 * return internet address info of interface to be used to get there. 960 */ 961 struct in_ifaddr * 962 ip_rtaddr(dst) 963 struct in_addr dst; 964 { 965 register struct sockaddr_in *sin; 966 967 sin = satosin(&ipforward_rt.ro_dst); 968 969 if (ipforward_rt.ro_rt == 0 || !in_hosteq(dst, sin->sin_addr)) { 970 if (ipforward_rt.ro_rt) { 971 RTFREE(ipforward_rt.ro_rt); 972 ipforward_rt.ro_rt = 0; 973 } 974 sin->sin_family = AF_INET; 975 sin->sin_len = sizeof(*sin); 976 sin->sin_addr = dst; 977 978 rtalloc(&ipforward_rt); 979 } 980 if (ipforward_rt.ro_rt == 0) 981 return ((struct in_ifaddr *)0); 982 return (ifatoia(ipforward_rt.ro_rt->rt_ifa)); 983 } 984 985 /* 986 * Save incoming source route for use in replies, 987 * to be picked up later by ip_srcroute if the receiver is interested. 988 */ 989 void 990 save_rte(option, dst) 991 u_char *option; 992 struct in_addr dst; 993 { 994 unsigned olen; 995 996 olen = option[IPOPT_OLEN]; 997 #ifdef DIAGNOSTIC 998 if (ipprintfs) 999 printf("save_rte: olen %d\n", olen); 1000 #endif 1001 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1002 return; 1003 bcopy((caddr_t)option, (caddr_t)ip_srcrt.srcopt, olen); 1004 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1005 ip_srcrt.dst = dst; 1006 } 1007 1008 /* 1009 * Retrieve incoming source route for use in replies, 1010 * in the same form used by setsockopt. 1011 * The first hop is placed before the options, will be removed later. 1012 */ 1013 struct mbuf * 1014 ip_srcroute() 1015 { 1016 register struct in_addr *p, *q; 1017 register struct mbuf *m; 1018 1019 if (ip_nhops == 0) 1020 return ((struct mbuf *)0); 1021 m = m_get(M_DONTWAIT, MT_SOOPTS); 1022 if (m == 0) 1023 return ((struct mbuf *)0); 1024 1025 #define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1026 1027 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1028 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1029 OPTSIZ; 1030 #ifdef DIAGNOSTIC 1031 if (ipprintfs) 1032 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1033 #endif 1034 1035 /* 1036 * First save first hop for return route 1037 */ 1038 p = &ip_srcrt.route[ip_nhops - 1]; 1039 *(mtod(m, struct in_addr *)) = *p--; 1040 #ifdef DIAGNOSTIC 1041 if (ipprintfs) 1042 printf(" hops %x", ntohl(mtod(m, struct in_addr *)->s_addr)); 1043 #endif 1044 1045 /* 1046 * Copy option fields and padding (nop) to mbuf. 1047 */ 1048 ip_srcrt.nop = IPOPT_NOP; 1049 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1050 bcopy((caddr_t)&ip_srcrt.nop, 1051 mtod(m, caddr_t) + sizeof(struct in_addr), OPTSIZ); 1052 q = (struct in_addr *)(mtod(m, caddr_t) + 1053 sizeof(struct in_addr) + OPTSIZ); 1054 #undef OPTSIZ 1055 /* 1056 * Record return path as an IP source route, 1057 * reversing the path (pointers are now aligned). 1058 */ 1059 while (p >= ip_srcrt.route) { 1060 #ifdef DIAGNOSTIC 1061 if (ipprintfs) 1062 printf(" %x", ntohl(q->s_addr)); 1063 #endif 1064 *q++ = *p--; 1065 } 1066 /* 1067 * Last hop goes to final destination. 1068 */ 1069 *q = ip_srcrt.dst; 1070 #ifdef DIAGNOSTIC 1071 if (ipprintfs) 1072 printf(" %x\n", ntohl(q->s_addr)); 1073 #endif 1074 return (m); 1075 } 1076 1077 /* 1078 * Strip out IP options, at higher 1079 * level protocol in the kernel. 1080 * Second argument is buffer to which options 1081 * will be moved, and return value is their length. 1082 * XXX should be deleted; last arg currently ignored. 1083 */ 1084 void 1085 ip_stripoptions(m, mopt) 1086 register struct mbuf *m; 1087 struct mbuf *mopt; 1088 { 1089 register int i; 1090 struct ip *ip = mtod(m, struct ip *); 1091 register caddr_t opts; 1092 int olen; 1093 1094 olen = (ip->ip_hl<<2) - sizeof (struct ip); 1095 opts = (caddr_t)(ip + 1); 1096 i = m->m_len - (sizeof (struct ip) + olen); 1097 bcopy(opts + olen, opts, (unsigned)i); 1098 m->m_len -= olen; 1099 if (m->m_flags & M_PKTHDR) 1100 m->m_pkthdr.len -= olen; 1101 ip->ip_hl = sizeof(struct ip) >> 2; 1102 } 1103 1104 int inetctlerrmap[PRC_NCMDS] = { 1105 0, 0, 0, 0, 1106 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1107 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1108 EMSGSIZE, EHOSTUNREACH, 0, 0, 1109 0, 0, 0, 0, 1110 ENOPROTOOPT 1111 }; 1112 1113 /* 1114 * Forward a packet. If some error occurs return the sender 1115 * an icmp packet. Note we can't always generate a meaningful 1116 * icmp message because icmp doesn't have a large enough repertoire 1117 * of codes and types. 1118 * 1119 * If not forwarding, just drop the packet. This could be confusing 1120 * if ipforwarding was zero but some routing protocol was advancing 1121 * us as a gateway to somewhere. However, we must let the routing 1122 * protocol deal with that. 1123 * 1124 * The srcrt parameter indicates whether the packet is being forwarded 1125 * via a source route. 1126 */ 1127 void 1128 ip_forward(m, srcrt) 1129 struct mbuf *m; 1130 int srcrt; 1131 { 1132 register struct ip *ip = mtod(m, struct ip *); 1133 register struct sockaddr_in *sin; 1134 register struct rtentry *rt; 1135 int error, type = 0, code = 0; 1136 struct mbuf *mcopy; 1137 n_long dest; 1138 struct ifnet *destifp; 1139 1140 dest = 0; 1141 #ifdef DIAGNOSTIC 1142 if (ipprintfs) 1143 printf("forward: src %2.2x dst %2.2x ttl %x\n", 1144 ntohl(ip->ip_src.s_addr), 1145 ntohl(ip->ip_dst.s_addr), ip->ip_ttl); 1146 #endif 1147 if (m->m_flags & M_BCAST || in_canforward(ip->ip_dst) == 0) { 1148 ipstat.ips_cantforward++; 1149 m_freem(m); 1150 return; 1151 } 1152 HTONS(ip->ip_id); 1153 if (ip->ip_ttl <= IPTTLDEC) { 1154 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1155 return; 1156 } 1157 ip->ip_ttl -= IPTTLDEC; 1158 1159 sin = satosin(&ipforward_rt.ro_dst); 1160 if ((rt = ipforward_rt.ro_rt) == 0 || 1161 !in_hosteq(ip->ip_dst, sin->sin_addr)) { 1162 if (ipforward_rt.ro_rt) { 1163 RTFREE(ipforward_rt.ro_rt); 1164 ipforward_rt.ro_rt = 0; 1165 } 1166 sin->sin_family = AF_INET; 1167 sin->sin_len = sizeof(struct sockaddr_in); 1168 sin->sin_addr = ip->ip_dst; 1169 1170 rtalloc(&ipforward_rt); 1171 if (ipforward_rt.ro_rt == 0) { 1172 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0); 1173 return; 1174 } 1175 rt = ipforward_rt.ro_rt; 1176 } 1177 1178 /* 1179 * Save at most 68 bytes of the packet in case 1180 * we need to generate an ICMP message to the src. 1181 */ 1182 mcopy = m_copy(m, 0, imin((int)ip->ip_len, 68)); 1183 1184 /* 1185 * If forwarding packet using same interface that it came in on, 1186 * perhaps should send a redirect to sender to shortcut a hop. 1187 * Only send redirect if source is sending directly to us, 1188 * and if packet was not source routed (or has any options). 1189 * Also, don't send redirect if forwarding using a default route 1190 * or a route modified by a redirect. 1191 */ 1192 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1193 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1194 !in_nullhost(satosin(rt_key(rt))->sin_addr) && 1195 ipsendredirects && !srcrt) { 1196 if (rt->rt_ifa && 1197 (ip->ip_src.s_addr & ifatoia(rt->rt_ifa)->ia_subnetmask) == 1198 ifatoia(rt->rt_ifa)->ia_subnet) { 1199 if (rt->rt_flags & RTF_GATEWAY) 1200 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1201 else 1202 dest = ip->ip_dst.s_addr; 1203 /* Router requirements says to only send host redirects */ 1204 type = ICMP_REDIRECT; 1205 code = ICMP_REDIRECT_HOST; 1206 #ifdef DIAGNOSTIC 1207 if (ipprintfs) 1208 printf("redirect (%d) to %x\n", code, (u_int32_t)dest); 1209 #endif 1210 } 1211 } 1212 1213 error = ip_output(m, (struct mbuf *)0, &ipforward_rt, 1214 (IP_FORWARDING | (ip_directedbcast ? IP_ALLOWBROADCAST : 0)), 0); 1215 if (error) 1216 ipstat.ips_cantforward++; 1217 else { 1218 ipstat.ips_forward++; 1219 if (type) 1220 ipstat.ips_redirectsent++; 1221 else { 1222 if (mcopy) { 1223 #ifdef GATEWAY 1224 if (mcopy->m_flags & M_CANFASTFWD) 1225 ipflow_create(&ipforward_rt, mcopy); 1226 #endif 1227 m_freem(mcopy); 1228 } 1229 return; 1230 } 1231 } 1232 if (mcopy == NULL) 1233 return; 1234 destifp = NULL; 1235 1236 switch (error) { 1237 1238 case 0: /* forwarded, but need redirect */ 1239 /* type, code set above */ 1240 break; 1241 1242 case ENETUNREACH: /* shouldn't happen, checked above */ 1243 case EHOSTUNREACH: 1244 case ENETDOWN: 1245 case EHOSTDOWN: 1246 default: 1247 type = ICMP_UNREACH; 1248 code = ICMP_UNREACH_HOST; 1249 break; 1250 1251 case EMSGSIZE: 1252 type = ICMP_UNREACH; 1253 code = ICMP_UNREACH_NEEDFRAG; 1254 if (ipforward_rt.ro_rt) 1255 destifp = ipforward_rt.ro_rt->rt_ifp; 1256 ipstat.ips_cantfrag++; 1257 break; 1258 1259 case ENOBUFS: 1260 type = ICMP_SOURCEQUENCH; 1261 code = 0; 1262 break; 1263 } 1264 icmp_error(mcopy, type, code, dest, destifp); 1265 } 1266 1267 void 1268 ip_savecontrol(inp, mp, ip, m) 1269 register struct inpcb *inp; 1270 register struct mbuf **mp; 1271 register struct ip *ip; 1272 register struct mbuf *m; 1273 { 1274 1275 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 1276 struct timeval tv; 1277 1278 microtime(&tv); 1279 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1280 SCM_TIMESTAMP, SOL_SOCKET); 1281 if (*mp) 1282 mp = &(*mp)->m_next; 1283 } 1284 if (inp->inp_flags & INP_RECVDSTADDR) { 1285 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst, 1286 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 1287 if (*mp) 1288 mp = &(*mp)->m_next; 1289 } 1290 #ifdef notyet 1291 /* 1292 * XXX 1293 * Moving these out of udp_input() made them even more broken 1294 * than they already were. 1295 * - fenner@parc.xerox.com 1296 */ 1297 /* options were tossed already */ 1298 if (inp->inp_flags & INP_RECVOPTS) { 1299 *mp = sbcreatecontrol((caddr_t) opts_deleted_above, 1300 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 1301 if (*mp) 1302 mp = &(*mp)->m_next; 1303 } 1304 /* ip_srcroute doesn't do what we want here, need to fix */ 1305 if (inp->inp_flags & INP_RECVRETOPTS) { 1306 *mp = sbcreatecontrol((caddr_t) ip_srcroute(), 1307 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 1308 if (*mp) 1309 mp = &(*mp)->m_next; 1310 } 1311 #endif 1312 if (inp->inp_flags & INP_RECVIF) { 1313 struct sockaddr_dl sdl; 1314 1315 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]); 1316 sdl.sdl_family = AF_LINK; 1317 sdl.sdl_index = m->m_pkthdr.rcvif ? 1318 m->m_pkthdr.rcvif->if_index : 0; 1319 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0; 1320 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len, 1321 IP_RECVIF, IPPROTO_IP); 1322 if (*mp) 1323 mp = &(*mp)->m_next; 1324 } 1325 } 1326 1327 int 1328 ip_sysctl(name, namelen, oldp, oldlenp, newp, newlen) 1329 int *name; 1330 u_int namelen; 1331 void *oldp; 1332 size_t *oldlenp; 1333 void *newp; 1334 size_t newlen; 1335 { 1336 extern int subnetsarelocal; 1337 1338 int error, old; 1339 1340 /* All sysctl names at this level are terminal. */ 1341 if (namelen != 1) 1342 return (ENOTDIR); 1343 1344 switch (name[0]) { 1345 case IPCTL_FORWARDING: 1346 return (sysctl_int(oldp, oldlenp, newp, newlen, &ipforwarding)); 1347 case IPCTL_SENDREDIRECTS: 1348 return (sysctl_int(oldp, oldlenp, newp, newlen, 1349 &ipsendredirects)); 1350 case IPCTL_DEFTTL: 1351 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_defttl)); 1352 #ifdef notyet 1353 case IPCTL_DEFMTU: 1354 return (sysctl_int(oldp, oldlenp, newp, newlen, &ip_mtu)); 1355 #endif 1356 case IPCTL_FORWSRCRT: 1357 /* Don't allow this to change in a secure environment. */ 1358 if (securelevel > 0) 1359 return (sysctl_rdint(oldp, oldlenp, newp, 1360 ip_forwsrcrt)); 1361 else 1362 return (sysctl_int(oldp, oldlenp, newp, newlen, 1363 &ip_forwsrcrt)); 1364 case IPCTL_DIRECTEDBCAST: 1365 return (sysctl_int(oldp, oldlenp, newp, newlen, 1366 &ip_directedbcast)); 1367 case IPCTL_ALLOWSRCRT: 1368 return (sysctl_int(oldp, oldlenp, newp, newlen, 1369 &ip_allowsrcrt)); 1370 case IPCTL_SUBNETSARELOCAL: 1371 return (sysctl_int(oldp, oldlenp, newp, newlen, 1372 &subnetsarelocal)); 1373 case IPCTL_MTUDISC: 1374 error = sysctl_int(oldp, oldlenp, newp, newlen, 1375 &ip_mtudisc); 1376 if (ip_mtudisc != 0 && ip_mtudisc_timeout_q == NULL) { 1377 ip_mtudisc_timeout_q = 1378 rt_timer_queue_create(ip_mtudisc_timeout); 1379 } else if (ip_mtudisc == 0 && ip_mtudisc_timeout_q != NULL) { 1380 rt_timer_queue_destroy(ip_mtudisc_timeout_q, TRUE); 1381 ip_mtudisc_timeout_q = NULL; 1382 } 1383 return error; 1384 case IPCTL_ANONPORTMIN: 1385 old = anonportmin; 1386 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmin); 1387 if (anonportmin >= anonportmax || anonportmin > 65535 1388 #ifndef IPNOPRIVPORTS 1389 || anonportmin < IPPORT_RESERVED 1390 #endif 1391 ) { 1392 anonportmin = old; 1393 return (EINVAL); 1394 } 1395 return (error); 1396 case IPCTL_ANONPORTMAX: 1397 old = anonportmax; 1398 error = sysctl_int(oldp, oldlenp, newp, newlen, &anonportmax); 1399 if (anonportmin >= anonportmax || anonportmax > 65535 1400 #ifndef IPNOPRIVPORTS 1401 || anonportmax < IPPORT_RESERVED 1402 #endif 1403 ) { 1404 anonportmax = old; 1405 return (EINVAL); 1406 } 1407 return (error); 1408 case IPCTL_MTUDISCTIMEOUT: 1409 error = sysctl_int(oldp, oldlenp, newp, newlen, 1410 &ip_mtudisc_timeout); 1411 if (ip_mtudisc_timeout_q != NULL) 1412 rt_timer_queue_change(ip_mtudisc_timeout_q, 1413 ip_mtudisc_timeout); 1414 return (error); 1415 #ifdef GATEWAY 1416 case IPCTL_MAXFLOWS: 1417 { 1418 int s; 1419 1420 error = sysctl_int(oldp, oldlenp, newp, newlen, 1421 &ip_maxflows); 1422 s = splsoftnet(); 1423 ipflow_reap(0); 1424 splx(s); 1425 return (error); 1426 } 1427 #endif 1428 default: 1429 return (EOPNOTSUPP); 1430 } 1431 /* NOTREACHED */ 1432 } 1433