ip_reass.c revision 22212
1/* 2 * Copyright (c) 1982, 1986, 1988, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 34 * $FreeBSD: head/sys/netinet/ip_input.c 22212 1997-02-02 16:33:12Z brian $ 35 * $ANA: ip_input.c,v 1.5 1996/09/18 14:34:59 wollman Exp $ 36 */ 37 38#define _IP_VHL 39 40#include "opt_ipfw.h" 41 42#include <stddef.h> 43 44#include <sys/param.h> 45#include <sys/systm.h> 46#include <sys/malloc.h> 47#include <sys/mbuf.h> 48#include <sys/domain.h> 49#include <sys/protosw.h> 50#include <sys/socket.h> 51#include <sys/errno.h> 52#include <sys/time.h> 53#include <sys/kernel.h> 54#include <sys/syslog.h> 55#include <sys/sysctl.h> 56 57#include <net/if.h> 58#include <net/if_dl.h> 59#include <net/route.h> 60#include <net/netisr.h> 61 62#include <netinet/in.h> 63#include <netinet/in_systm.h> 64#include <netinet/in_var.h> 65#include <netinet/ip.h> 66#include <netinet/in_pcb.h> 67#include <netinet/in_var.h> 68#include <netinet/ip_var.h> 69#include <netinet/ip_icmp.h> 70#include <machine/in_cksum.h> 71 72#include <sys/socketvar.h> 73 74#ifdef IPFIREWALL 75#include <netinet/ip_fw.h> 76#endif 77 78int rsvp_on = 0; 79static int ip_rsvp_on; 80struct socket *ip_rsvpd; 81 82static int ipforwarding = 0; 83SYSCTL_INT(_net_inet_ip, IPCTL_FORWARDING, forwarding, CTLFLAG_RW, 84 &ipforwarding, 0, ""); 85 86static int ipsendredirects = 1; /* XXX */ 87SYSCTL_INT(_net_inet_ip, IPCTL_SENDREDIRECTS, redirect, CTLFLAG_RW, 88 &ipsendredirects, 0, ""); 89 90int ip_defttl = IPDEFTTL; 91SYSCTL_INT(_net_inet_ip, IPCTL_DEFTTL, ttl, CTLFLAG_RW, 92 &ip_defttl, 0, ""); 93 94static int ip_dosourceroute = 0; 95SYSCTL_INT(_net_inet_ip, IPCTL_SOURCEROUTE, sourceroute, CTLFLAG_RW, 96 &ip_dosourceroute, 0, ""); 97#ifdef DIAGNOSTIC 98static int ipprintfs = 0; 99#endif 100 101extern struct domain inetdomain; 102extern struct protosw inetsw[]; 103u_char ip_protox[IPPROTO_MAX]; 104static int ipqmaxlen = IFQ_MAXLEN; 105struct in_ifaddrhead in_ifaddrhead; /* first inet address */ 106struct ifqueue ipintrq; 107SYSCTL_INT(_net_inet_ip, IPCTL_INTRQMAXLEN, intr_queue_maxlen, CTLFLAG_RD, 108 &ipintrq.ifq_maxlen, 0, ""); 109SYSCTL_INT(_net_inet_ip, IPCTL_INTRQDROPS, intr_queue_drops, CTLFLAG_RD, 110 &ipintrq.ifq_drops, 0, ""); 111 112struct ipstat ipstat; 113static struct ipq ipq; 114 115#ifdef IPCTL_DEFMTU 116SYSCTL_INT(_net_inet_ip, IPCTL_DEFMTU, mtu, CTLFLAG_RW, 117 &ip_mtu, 0, ""); 118#endif 119 120#if !defined(COMPAT_IPFW) || COMPAT_IPFW == 1 121#undef COMPAT_IPFW 122#define COMPAT_IPFW 1 123#else 124#undef COMPAT_IPFW 125#endif 126 127#ifdef COMPAT_IPFW 128/* Firewall hooks */ 129ip_fw_chk_t *ip_fw_chk_ptr; 130ip_fw_ctl_t *ip_fw_ctl_ptr; 131 132/* IP Network Address Translation (NAT) hooks */ 133ip_nat_t *ip_nat_ptr; 134ip_nat_ctl_t *ip_nat_ctl_ptr; 135#endif 136 137/* 138 * We need to save the IP options in case a protocol wants to respond 139 * to an incoming packet over the same route if the packet got here 140 * using IP source routing. This allows connection establishment and 141 * maintenance when the remote end is on a network that is not known 142 * to us. 143 */ 144static int ip_nhops = 0; 145static struct ip_srcrt { 146 struct in_addr dst; /* final destination */ 147 char nop; /* one NOP to align */ 148 char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */ 149 struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)]; 150} ip_srcrt; 151 152#ifdef IPDIVERT 153/* 154 * Shared variable between ip_input() and ip_reass() to communicate 155 * about which packets, once assembled from fragments, get diverted, 156 * and to which port. 157 */ 158static u_short frag_divert_port; 159#endif 160 161static void save_rte __P((u_char *, struct in_addr)); 162static void ip_deq __P((struct ipasfrag *)); 163static int ip_dooptions __P((struct mbuf *)); 164static void ip_enq __P((struct ipasfrag *, struct ipasfrag *)); 165static void ip_forward __P((struct mbuf *, int)); 166static void ip_freef __P((struct ipq *)); 167static struct ip * 168 ip_reass __P((struct ipasfrag *, struct ipq *)); 169static struct in_ifaddr * 170 ip_rtaddr __P((struct in_addr)); 171static void ipintr __P((void)); 172/* 173 * IP initialization: fill in IP protocol switch table. 174 * All protocols not implemented in kernel go to raw IP protocol handler. 175 */ 176void 177ip_init() 178{ 179 register struct protosw *pr; 180 register int i; 181 182 TAILQ_INIT(&in_ifaddrhead); 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 ipq.next = ipq.prev = &ipq; 194 ip_id = time.tv_sec & 0xffff; 195 ipintrq.ifq_maxlen = ipqmaxlen; 196#ifdef IPFIREWALL 197 ip_fw_init(); 198#endif 199#ifdef IPNAT 200 ip_nat_init(); 201#endif 202 203} 204 205static struct sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET }; 206static struct route ipforward_rt; 207 208/* 209 * Ip input routine. Checksum and byte swap header. If fragmented 210 * try to reassemble. Process options. Pass to next level. 211 */ 212void 213ip_input(struct mbuf *m) 214{ 215 struct ip *ip; 216 struct ipq *fp; 217 struct in_ifaddr *ia; 218 int hlen; 219 220#ifdef DIAGNOSTIC 221 if ((m->m_flags & M_PKTHDR) == 0) 222 panic("ip_input no HDR"); 223#endif 224 /* 225 * If no IP addresses have been set yet but the interfaces 226 * are receiving, can't do anything with incoming packets yet. 227 * XXX This is broken! We should be able to receive broadcasts 228 * and multicasts even without any local addresses configured. 229 */ 230 if (TAILQ_EMPTY(&in_ifaddrhead)) 231 goto bad; 232 ipstat.ips_total++; 233 234 if (m->m_pkthdr.len < sizeof(struct ip)) 235 goto tooshort; 236 237#ifdef DIAGNOSTIC 238 if (m->m_len < sizeof(struct ip)) 239 panic("ipintr mbuf too short"); 240#endif 241 242 if (m->m_len < sizeof (struct ip) && 243 (m = m_pullup(m, sizeof (struct ip))) == 0) { 244 ipstat.ips_toosmall++; 245 return; 246 } 247 ip = mtod(m, struct ip *); 248 249 if (IP_VHL_V(ip->ip_vhl) != IPVERSION) { 250 ipstat.ips_badvers++; 251 goto bad; 252 } 253 254 hlen = IP_VHL_HL(ip->ip_vhl) << 2; 255 if (hlen < sizeof(struct ip)) { /* minimum header length */ 256 ipstat.ips_badhlen++; 257 goto bad; 258 } 259 if (hlen > m->m_len) { 260 if ((m = m_pullup(m, hlen)) == 0) { 261 ipstat.ips_badhlen++; 262 return; 263 } 264 ip = mtod(m, struct ip *); 265 } 266 if (hlen == sizeof(struct ip)) { 267 ip->ip_sum = in_cksum_hdr(ip); 268 } else { 269 ip->ip_sum = in_cksum(m, hlen); 270 } 271 if (ip->ip_sum) { 272 ipstat.ips_badsum++; 273 goto bad; 274 } 275 276 /* 277 * Convert fields to host representation. 278 */ 279 NTOHS(ip->ip_len); 280 if (ip->ip_len < hlen) { 281 ipstat.ips_badlen++; 282 goto bad; 283 } 284 NTOHS(ip->ip_id); 285 NTOHS(ip->ip_off); 286 287 /* 288 * Check that the amount of data in the buffers 289 * is as at least much as the IP header would have us expect. 290 * Trim mbufs if longer than we expect. 291 * Drop packet if shorter than we expect. 292 */ 293 if (m->m_pkthdr.len < ip->ip_len) { 294tooshort: 295 ipstat.ips_tooshort++; 296 goto bad; 297 } 298 if (m->m_pkthdr.len > ip->ip_len) { 299 if (m->m_len == m->m_pkthdr.len) { 300 m->m_len = ip->ip_len; 301 m->m_pkthdr.len = ip->ip_len; 302 } else 303 m_adj(m, ip->ip_len - m->m_pkthdr.len); 304 } 305 /* 306 * IpHack's section. 307 * Right now when no processing on packet has done 308 * and it is still fresh out of network we do our black 309 * deals with it. 310 * - Firewall: deny/allow/divert 311 * - Xlate: translate packet's addr/port (NAT). 312 * - Wrap: fake packet's addr/port <unimpl.> 313 * - Encapsulate: put it in another IP and send out. <unimp.> 314 */ 315 316#ifdef COMPAT_IPFW 317 if (ip_fw_chk_ptr) { 318 int action; 319 320#ifdef IPDIVERT 321 action = (*ip_fw_chk_ptr)(&ip, hlen, 322 m->m_pkthdr.rcvif, ip_divert_ignore, &m); 323 ip_divert_ignore = 0; 324#else 325 action = (*ip_fw_chk_ptr)(&ip, hlen, m->m_pkthdr.rcvif, 0, &m); 326#endif 327 if (action == -1) 328 return; 329 if (action != 0) { 330#ifdef IPDIVERT 331 frag_divert_port = action; 332 goto ours; 333#else 334 goto bad; /* ipfw said divert but we can't */ 335#endif 336 } 337 } 338 339 if (ip_nat_ptr && !(*ip_nat_ptr)(&ip, &m, m->m_pkthdr.rcvif, IP_NAT_IN)) 340 return; 341#endif 342 343 /* 344 * Process options and, if not destined for us, 345 * ship it on. ip_dooptions returns 1 when an 346 * error was detected (causing an icmp message 347 * to be sent and the original packet to be freed). 348 */ 349 ip_nhops = 0; /* for source routed packets */ 350 if (hlen > sizeof (struct ip) && ip_dooptions(m)) 351 return; 352 353 /* greedy RSVP, snatches any PATH packet of the RSVP protocol and no 354 * matter if it is destined to another node, or whether it is 355 * a multicast one, RSVP wants it! and prevents it from being forwarded 356 * anywhere else. Also checks if the rsvp daemon is running before 357 * grabbing the packet. 358 */ 359 if (rsvp_on && ip->ip_p==IPPROTO_RSVP) 360 goto ours; 361 362 /* 363 * Check our list of addresses, to see if the packet is for us. 364 */ 365 for (ia = in_ifaddrhead.tqh_first; ia; ia = ia->ia_link.tqe_next) { 366#define satosin(sa) ((struct sockaddr_in *)(sa)) 367 368 if (IA_SIN(ia)->sin_addr.s_addr == ip->ip_dst.s_addr) 369 goto ours; 370 if (ia->ia_ifp && ia->ia_ifp->if_flags & IFF_BROADCAST) { 371 if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr == 372 ip->ip_dst.s_addr) 373 goto ours; 374 if (ip->ip_dst.s_addr == ia->ia_netbroadcast.s_addr) 375 goto ours; 376 } 377 } 378 if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { 379 struct in_multi *inm; 380 if (ip_mrouter) { 381 /* 382 * If we are acting as a multicast router, all 383 * incoming multicast packets are passed to the 384 * kernel-level multicast forwarding function. 385 * The packet is returned (relatively) intact; if 386 * ip_mforward() returns a non-zero value, the packet 387 * must be discarded, else it may be accepted below. 388 * 389 * (The IP ident field is put in the same byte order 390 * as expected when ip_mforward() is called from 391 * ip_output().) 392 */ 393 ip->ip_id = htons(ip->ip_id); 394 if (ip_mforward(ip, m->m_pkthdr.rcvif, m, 0) != 0) { 395 ipstat.ips_cantforward++; 396 m_freem(m); 397 return; 398 } 399 ip->ip_id = ntohs(ip->ip_id); 400 401 /* 402 * The process-level routing demon needs to receive 403 * all multicast IGMP packets, whether or not this 404 * host belongs to their destination groups. 405 */ 406 if (ip->ip_p == IPPROTO_IGMP) 407 goto ours; 408 ipstat.ips_forward++; 409 } 410 /* 411 * See if we belong to the destination multicast group on the 412 * arrival interface. 413 */ 414 IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); 415 if (inm == NULL) { 416 ipstat.ips_notmember++; 417 m_freem(m); 418 return; 419 } 420 goto ours; 421 } 422 if (ip->ip_dst.s_addr == (u_long)INADDR_BROADCAST) 423 goto ours; 424 if (ip->ip_dst.s_addr == INADDR_ANY) 425 goto ours; 426 427 /* 428 * Not for us; forward if possible and desirable. 429 */ 430 if (ipforwarding == 0) { 431 ipstat.ips_cantforward++; 432 m_freem(m); 433 } else 434 ip_forward(m, 0); 435 return; 436 437ours: 438 439 /* 440 * If offset or IP_MF are set, must reassemble. 441 * Otherwise, nothing need be done. 442 * (We could look in the reassembly queue to see 443 * if the packet was previously fragmented, 444 * but it's not worth the time; just let them time out.) 445 */ 446 if (ip->ip_off & (IP_MF | IP_OFFMASK)) { 447 if (m->m_flags & M_EXT) { /* XXX */ 448 if ((m = m_pullup(m, sizeof (struct ip))) == 0) { 449 ipstat.ips_toosmall++; 450#ifdef IPDIVERT 451 frag_divert_port = 0; 452#endif 453 return; 454 } 455 ip = mtod(m, struct ip *); 456 } 457 /* 458 * Look for queue of fragments 459 * of this datagram. 460 */ 461 for (fp = ipq.next; fp != &ipq; fp = fp->next) 462 if (ip->ip_id == fp->ipq_id && 463 ip->ip_src.s_addr == fp->ipq_src.s_addr && 464 ip->ip_dst.s_addr == fp->ipq_dst.s_addr && 465 ip->ip_p == fp->ipq_p) 466 goto found; 467 fp = 0; 468found: 469 470 /* 471 * Adjust ip_len to not reflect header, 472 * set ip_mff if more fragments are expected, 473 * convert offset of this to bytes. 474 */ 475 ip->ip_len -= hlen; 476 ((struct ipasfrag *)ip)->ipf_mff &= ~1; 477 if (ip->ip_off & IP_MF) 478 ((struct ipasfrag *)ip)->ipf_mff |= 1; 479 ip->ip_off <<= 3; 480 481 /* 482 * If datagram marked as having more fragments 483 * or if this is not the first fragment, 484 * attempt reassembly; if it succeeds, proceed. 485 */ 486 if (((struct ipasfrag *)ip)->ipf_mff & 1 || ip->ip_off) { 487 ipstat.ips_fragments++; 488 ip = ip_reass((struct ipasfrag *)ip, fp); 489 if (ip == 0) 490 return; 491 ipstat.ips_reassembled++; 492 m = dtom(ip); 493 } else 494 if (fp) 495 ip_freef(fp); 496 } else 497 ip->ip_len -= hlen; 498 499#ifdef IPDIVERT 500 /* 501 * Divert packets here to the divert protocol if required 502 */ 503 if (frag_divert_port) { 504 ip_divert_port = frag_divert_port; 505 frag_divert_port = 0; 506 (*inetsw[ip_protox[IPPROTO_DIVERT]].pr_input)(m, hlen); 507 return; 508 } 509#endif 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 return; 517bad: 518 m_freem(m); 519} 520 521/* 522 * IP software interrupt routine - to go away sometime soon 523 */ 524static void 525ipintr(void) 526{ 527 int s; 528 struct mbuf *m; 529 530 while(1) { 531 s = splimp(); 532 IF_DEQUEUE(&ipintrq, m); 533 splx(s); 534 if (m == 0) 535 return; 536 ip_input(m); 537 } 538} 539 540NETISR_SET(NETISR_IP, ipintr); 541 542/* 543 * Take incoming datagram fragment and try to 544 * reassemble it into whole datagram. If a chain for 545 * reassembly of this datagram already exists, then it 546 * is given as fp; otherwise have to make a chain. 547 */ 548static struct ip * 549ip_reass(ip, fp) 550 register struct ipasfrag *ip; 551 register struct ipq *fp; 552{ 553 register struct mbuf *m = dtom(ip); 554 register struct ipasfrag *q; 555 struct mbuf *t; 556 int hlen = ip->ip_hl << 2; 557 int i, next; 558 559 /* 560 * Presence of header sizes in mbufs 561 * would confuse code below. 562 */ 563 m->m_data += hlen; 564 m->m_len -= hlen; 565 566 /* 567 * If first fragment to arrive, create a reassembly queue. 568 */ 569 if (fp == 0) { 570 if ((t = m_get(M_DONTWAIT, MT_FTABLE)) == NULL) 571 goto dropfrag; 572 fp = mtod(t, struct ipq *); 573 insque(fp, &ipq); 574 fp->ipq_ttl = IPFRAGTTL; 575 fp->ipq_p = ip->ip_p; 576 fp->ipq_id = ip->ip_id; 577 fp->ipq_next = fp->ipq_prev = (struct ipasfrag *)fp; 578 fp->ipq_src = ((struct ip *)ip)->ip_src; 579 fp->ipq_dst = ((struct ip *)ip)->ip_dst; 580#ifdef IPDIVERT 581 fp->ipq_divert = 0; 582#endif 583 q = (struct ipasfrag *)fp; 584 goto insert; 585 } 586 587 /* 588 * Find a segment which begins after this one does. 589 */ 590 for (q = fp->ipq_next; q != (struct ipasfrag *)fp; q = q->ipf_next) 591 if (q->ip_off > ip->ip_off) 592 break; 593 594 /* 595 * If there is a preceding segment, it may provide some of 596 * our data already. If so, drop the data from the incoming 597 * segment. If it provides all of our data, drop us. 598 */ 599 if (q->ipf_prev != (struct ipasfrag *)fp) { 600 i = q->ipf_prev->ip_off + q->ipf_prev->ip_len - ip->ip_off; 601 if (i > 0) { 602 if (i >= ip->ip_len) 603 goto dropfrag; 604 m_adj(dtom(ip), i); 605 ip->ip_off += i; 606 ip->ip_len -= i; 607 } 608 } 609 610 /* 611 * While we overlap succeeding segments trim them or, 612 * if they are completely covered, dequeue them. 613 */ 614 while (q != (struct ipasfrag *)fp && ip->ip_off + ip->ip_len > q->ip_off) { 615 struct mbuf *m0; 616 617 i = (ip->ip_off + ip->ip_len) - q->ip_off; 618 if (i < q->ip_len) { 619 q->ip_len -= i; 620 q->ip_off += i; 621 m_adj(dtom(q), i); 622 break; 623 } 624 m0 = dtom(q); 625 q = q->ipf_next; 626 ip_deq(q->ipf_prev); 627 m_freem(m0); 628 } 629 630insert: 631 632#ifdef IPDIVERT 633 /* 634 * Any fragment diverting causes the whole packet to divert 635 */ 636 if (frag_divert_port != 0) 637 fp->ipq_divert = frag_divert_port; 638 frag_divert_port = 0; 639#endif 640 641 /* 642 * Stick new segment in its place; 643 * check for complete reassembly. 644 */ 645 ip_enq(ip, q->ipf_prev); 646 next = 0; 647 for (q = fp->ipq_next; q != (struct ipasfrag *)fp; q = q->ipf_next) { 648 if (q->ip_off != next) 649 return (0); 650 next += q->ip_len; 651 } 652 if (q->ipf_prev->ipf_mff & 1) 653 return (0); 654 655 /* 656 * Reassembly is complete. Make sure the packet is a sane size. 657 */ 658 if (next + (IP_VHL_HL(((struct ip *)fp->ipq_next)->ip_vhl) << 2) 659 > IP_MAXPACKET) { 660 ipstat.ips_toolong++; 661 ip_freef(fp); 662 return (0); 663 } 664 665 /* 666 * Concatenate fragments. 667 */ 668 q = fp->ipq_next; 669 m = dtom(q); 670 t = m->m_next; 671 m->m_next = 0; 672 m_cat(m, t); 673 q = q->ipf_next; 674 while (q != (struct ipasfrag *)fp) { 675 t = dtom(q); 676 q = q->ipf_next; 677 m_cat(m, t); 678 } 679 680#ifdef IPDIVERT 681 /* 682 * Record divert port for packet, if any 683 */ 684 frag_divert_port = fp->ipq_divert; 685#endif 686 687 /* 688 * Create header for new ip packet by 689 * modifying header of first packet; 690 * dequeue and discard fragment reassembly header. 691 * Make header visible. 692 */ 693 ip = fp->ipq_next; 694 ip->ip_len = next; 695 ip->ipf_mff &= ~1; 696 ((struct ip *)ip)->ip_src = fp->ipq_src; 697 ((struct ip *)ip)->ip_dst = fp->ipq_dst; 698 remque(fp); 699 (void) m_free(dtom(fp)); 700 m = dtom(ip); 701 m->m_len += (ip->ip_hl << 2); 702 m->m_data -= (ip->ip_hl << 2); 703 /* some debugging cruft by sklower, below, will go away soon */ 704 if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ 705 register int plen = 0; 706 for (t = m; m; m = m->m_next) 707 plen += m->m_len; 708 t->m_pkthdr.len = plen; 709 } 710 return ((struct ip *)ip); 711 712dropfrag: 713 ipstat.ips_fragdropped++; 714 m_freem(m); 715 return (0); 716} 717 718/* 719 * Free a fragment reassembly header and all 720 * associated datagrams. 721 */ 722static void 723ip_freef(fp) 724 struct ipq *fp; 725{ 726 register struct ipasfrag *q, *p; 727 728 for (q = fp->ipq_next; q != (struct ipasfrag *)fp; q = p) { 729 p = q->ipf_next; 730 ip_deq(q); 731 m_freem(dtom(q)); 732 } 733 remque(fp); 734 (void) m_free(dtom(fp)); 735} 736 737/* 738 * Put an ip fragment on a reassembly chain. 739 * Like insque, but pointers in middle of structure. 740 */ 741static void 742ip_enq(p, prev) 743 register struct ipasfrag *p, *prev; 744{ 745 746 p->ipf_prev = prev; 747 p->ipf_next = prev->ipf_next; 748 prev->ipf_next->ipf_prev = p; 749 prev->ipf_next = p; 750} 751 752/* 753 * To ip_enq as remque is to insque. 754 */ 755static void 756ip_deq(p) 757 register struct ipasfrag *p; 758{ 759 760 p->ipf_prev->ipf_next = p->ipf_next; 761 p->ipf_next->ipf_prev = p->ipf_prev; 762} 763 764/* 765 * IP timer processing; 766 * if a timer expires on a reassembly 767 * queue, discard it. 768 */ 769void 770ip_slowtimo() 771{ 772 register struct ipq *fp; 773 int s = splnet(); 774 775 fp = ipq.next; 776 if (fp == 0) { 777 splx(s); 778 return; 779 } 780 while (fp != &ipq) { 781 --fp->ipq_ttl; 782 fp = fp->next; 783 if (fp->prev->ipq_ttl == 0) { 784 ipstat.ips_fragtimeout++; 785 ip_freef(fp->prev); 786 } 787 } 788 splx(s); 789} 790 791/* 792 * Drain off all datagram fragments. 793 */ 794void 795ip_drain() 796{ 797 while (ipq.next != &ipq) { 798 ipstat.ips_fragdropped++; 799 ip_freef(ipq.next); 800 } 801 802 in_rtqdrain(); 803} 804 805/* 806 * Do option processing on a datagram, 807 * possibly discarding it if bad options are encountered, 808 * or forwarding it if source-routed. 809 * Returns 1 if packet has been forwarded/freed, 810 * 0 if the packet should be processed further. 811 */ 812static int 813ip_dooptions(m) 814 struct mbuf *m; 815{ 816 register struct ip *ip = mtod(m, struct ip *); 817 register u_char *cp; 818 register struct ip_timestamp *ipt; 819 register struct in_ifaddr *ia; 820 int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; 821 struct in_addr *sin, dst; 822 n_time ntime; 823 824 dst = ip->ip_dst; 825 cp = (u_char *)(ip + 1); 826 cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof (struct ip); 827 for (; cnt > 0; cnt -= optlen, cp += optlen) { 828 opt = cp[IPOPT_OPTVAL]; 829 if (opt == IPOPT_EOL) 830 break; 831 if (opt == IPOPT_NOP) 832 optlen = 1; 833 else { 834 optlen = cp[IPOPT_OLEN]; 835 if (optlen <= 0 || optlen > cnt) { 836 code = &cp[IPOPT_OLEN] - (u_char *)ip; 837 goto bad; 838 } 839 } 840 switch (opt) { 841 842 default: 843 break; 844 845 /* 846 * Source routing with record. 847 * Find interface with current destination address. 848 * If none on this machine then drop if strictly routed, 849 * or do nothing if loosely routed. 850 * Record interface address and bring up next address 851 * component. If strictly routed make sure next 852 * address is on directly accessible net. 853 */ 854 case IPOPT_LSRR: 855 case IPOPT_SSRR: 856 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 857 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 858 goto bad; 859 } 860 ipaddr.sin_addr = ip->ip_dst; 861 ia = (struct in_ifaddr *) 862 ifa_ifwithaddr((struct sockaddr *)&ipaddr); 863 if (ia == 0) { 864 if (opt == IPOPT_SSRR) { 865 type = ICMP_UNREACH; 866 code = ICMP_UNREACH_SRCFAIL; 867 goto bad; 868 } 869 /* 870 * Loose routing, and not at next destination 871 * yet; nothing to do except forward. 872 */ 873 break; 874 } 875 off--; /* 0 origin */ 876 if (off > optlen - sizeof(struct in_addr)) { 877 /* 878 * End of source route. Should be for us. 879 */ 880 save_rte(cp, ip->ip_src); 881 break; 882 } 883 884 if (!ip_dosourceroute) { 885 char buf[4*sizeof "123"]; 886 strcpy(buf, inet_ntoa(ip->ip_dst)); 887 888 log(LOG_WARNING, 889 "attempted source route from %s to %s\n", 890 inet_ntoa(ip->ip_src), buf); 891 type = ICMP_UNREACH; 892 code = ICMP_UNREACH_SRCFAIL; 893 goto bad; 894 } 895 896 /* 897 * locate outgoing interface 898 */ 899 (void)memcpy(&ipaddr.sin_addr, cp + off, 900 sizeof(ipaddr.sin_addr)); 901 902 if (opt == IPOPT_SSRR) { 903#define INA struct in_ifaddr * 904#define SA struct sockaddr * 905 if ((ia = (INA)ifa_ifwithdstaddr((SA)&ipaddr)) == 0) 906 ia = (INA)ifa_ifwithnet((SA)&ipaddr); 907 } else 908 ia = ip_rtaddr(ipaddr.sin_addr); 909 if (ia == 0) { 910 type = ICMP_UNREACH; 911 code = ICMP_UNREACH_SRCFAIL; 912 goto bad; 913 } 914 ip->ip_dst = ipaddr.sin_addr; 915 (void)memcpy(cp + off, &(IA_SIN(ia)->sin_addr), 916 sizeof(struct in_addr)); 917 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 918 /* 919 * Let ip_intr's mcast routing check handle mcast pkts 920 */ 921 forward = !IN_MULTICAST(ntohl(ip->ip_dst.s_addr)); 922 break; 923 924 case IPOPT_RR: 925 if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { 926 code = &cp[IPOPT_OFFSET] - (u_char *)ip; 927 goto bad; 928 } 929 /* 930 * If no space remains, ignore. 931 */ 932 off--; /* 0 origin */ 933 if (off > optlen - sizeof(struct in_addr)) 934 break; 935 (void)memcpy(&ipaddr.sin_addr, &ip->ip_dst, 936 sizeof(ipaddr.sin_addr)); 937 /* 938 * locate outgoing interface; if we're the destination, 939 * use the incoming interface (should be same). 940 */ 941 if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0 && 942 (ia = ip_rtaddr(ipaddr.sin_addr)) == 0) { 943 type = ICMP_UNREACH; 944 code = ICMP_UNREACH_HOST; 945 goto bad; 946 } 947 (void)memcpy(cp + off, &(IA_SIN(ia)->sin_addr), 948 sizeof(struct in_addr)); 949 cp[IPOPT_OFFSET] += sizeof(struct in_addr); 950 break; 951 952 case IPOPT_TS: 953 code = cp - (u_char *)ip; 954 ipt = (struct ip_timestamp *)cp; 955 if (ipt->ipt_len < 5) 956 goto bad; 957 if (ipt->ipt_ptr > ipt->ipt_len - sizeof (long)) { 958 if (++ipt->ipt_oflw == 0) 959 goto bad; 960 break; 961 } 962 sin = (struct in_addr *)(cp + ipt->ipt_ptr - 1); 963 switch (ipt->ipt_flg) { 964 965 case IPOPT_TS_TSONLY: 966 break; 967 968 case IPOPT_TS_TSANDADDR: 969 if (ipt->ipt_ptr + sizeof(n_time) + 970 sizeof(struct in_addr) > ipt->ipt_len) 971 goto bad; 972 ipaddr.sin_addr = dst; 973 ia = (INA)ifaof_ifpforaddr((SA)&ipaddr, 974 m->m_pkthdr.rcvif); 975 if (ia == 0) 976 continue; 977 (void)memcpy(sin, &IA_SIN(ia)->sin_addr, 978 sizeof(struct in_addr)); 979 ipt->ipt_ptr += sizeof(struct in_addr); 980 break; 981 982 case IPOPT_TS_PRESPEC: 983 if (ipt->ipt_ptr + sizeof(n_time) + 984 sizeof(struct in_addr) > ipt->ipt_len) 985 goto bad; 986 (void)memcpy(&ipaddr.sin_addr, sin, 987 sizeof(struct in_addr)); 988 if (ifa_ifwithaddr((SA)&ipaddr) == 0) 989 continue; 990 ipt->ipt_ptr += sizeof(struct in_addr); 991 break; 992 993 default: 994 goto bad; 995 } 996 ntime = iptime(); 997 (void)memcpy(cp + ipt->ipt_ptr - 1, &ntime, 998 sizeof(n_time)); 999 ipt->ipt_ptr += sizeof(n_time); 1000 } 1001 } 1002 if (forward) { 1003 ip_forward(m, 1); 1004 return (1); 1005 } 1006 return (0); 1007bad: 1008 ip->ip_len -= IP_VHL_HL(ip->ip_vhl) << 2; /* XXX icmp_error adds in hdr length */ 1009 icmp_error(m, type, code, 0, 0); 1010 ipstat.ips_badoptions++; 1011 return (1); 1012} 1013 1014/* 1015 * Given address of next destination (final or next hop), 1016 * return internet address info of interface to be used to get there. 1017 */ 1018static struct in_ifaddr * 1019ip_rtaddr(dst) 1020 struct in_addr dst; 1021{ 1022 register struct sockaddr_in *sin; 1023 1024 sin = (struct sockaddr_in *) &ipforward_rt.ro_dst; 1025 1026 if (ipforward_rt.ro_rt == 0 || dst.s_addr != sin->sin_addr.s_addr) { 1027 if (ipforward_rt.ro_rt) { 1028 RTFREE(ipforward_rt.ro_rt); 1029 ipforward_rt.ro_rt = 0; 1030 } 1031 sin->sin_family = AF_INET; 1032 sin->sin_len = sizeof(*sin); 1033 sin->sin_addr = dst; 1034 1035 rtalloc_ign(&ipforward_rt, RTF_PRCLONING); 1036 } 1037 if (ipforward_rt.ro_rt == 0) 1038 return ((struct in_ifaddr *)0); 1039 return ((struct in_ifaddr *) ipforward_rt.ro_rt->rt_ifa); 1040} 1041 1042/* 1043 * Save incoming source route for use in replies, 1044 * to be picked up later by ip_srcroute if the receiver is interested. 1045 */ 1046void 1047save_rte(option, dst) 1048 u_char *option; 1049 struct in_addr dst; 1050{ 1051 unsigned olen; 1052 1053 olen = option[IPOPT_OLEN]; 1054#ifdef DIAGNOSTIC 1055 if (ipprintfs) 1056 printf("save_rte: olen %d\n", olen); 1057#endif 1058 if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) 1059 return; 1060 bcopy(option, ip_srcrt.srcopt, olen); 1061 ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); 1062 ip_srcrt.dst = dst; 1063} 1064 1065/* 1066 * Retrieve incoming source route for use in replies, 1067 * in the same form used by setsockopt. 1068 * The first hop is placed before the options, will be removed later. 1069 */ 1070struct mbuf * 1071ip_srcroute() 1072{ 1073 register struct in_addr *p, *q; 1074 register struct mbuf *m; 1075 1076 if (ip_nhops == 0) 1077 return ((struct mbuf *)0); 1078 m = m_get(M_DONTWAIT, MT_SOOPTS); 1079 if (m == 0) 1080 return ((struct mbuf *)0); 1081 1082#define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) 1083 1084 /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ 1085 m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + 1086 OPTSIZ; 1087#ifdef DIAGNOSTIC 1088 if (ipprintfs) 1089 printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); 1090#endif 1091 1092 /* 1093 * First save first hop for return route 1094 */ 1095 p = &ip_srcrt.route[ip_nhops - 1]; 1096 *(mtod(m, struct in_addr *)) = *p--; 1097#ifdef DIAGNOSTIC 1098 if (ipprintfs) 1099 printf(" hops %lx", ntohl(mtod(m, struct in_addr *)->s_addr)); 1100#endif 1101 1102 /* 1103 * Copy option fields and padding (nop) to mbuf. 1104 */ 1105 ip_srcrt.nop = IPOPT_NOP; 1106 ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; 1107 (void)memcpy(mtod(m, caddr_t) + sizeof(struct in_addr), 1108 &ip_srcrt.nop, OPTSIZ); 1109 q = (struct in_addr *)(mtod(m, caddr_t) + 1110 sizeof(struct in_addr) + OPTSIZ); 1111#undef OPTSIZ 1112 /* 1113 * Record return path as an IP source route, 1114 * reversing the path (pointers are now aligned). 1115 */ 1116 while (p >= ip_srcrt.route) { 1117#ifdef DIAGNOSTIC 1118 if (ipprintfs) 1119 printf(" %lx", ntohl(q->s_addr)); 1120#endif 1121 *q++ = *p--; 1122 } 1123 /* 1124 * Last hop goes to final destination. 1125 */ 1126 *q = ip_srcrt.dst; 1127#ifdef DIAGNOSTIC 1128 if (ipprintfs) 1129 printf(" %lx\n", ntohl(q->s_addr)); 1130#endif 1131 return (m); 1132} 1133 1134/* 1135 * Strip out IP options, at higher 1136 * level protocol in the kernel. 1137 * Second argument is buffer to which options 1138 * will be moved, and return value is their length. 1139 * XXX should be deleted; last arg currently ignored. 1140 */ 1141void 1142ip_stripoptions(m, mopt) 1143 register struct mbuf *m; 1144 struct mbuf *mopt; 1145{ 1146 register int i; 1147 struct ip *ip = mtod(m, struct ip *); 1148 register caddr_t opts; 1149 int olen; 1150 1151 olen = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof (struct ip); 1152 opts = (caddr_t)(ip + 1); 1153 i = m->m_len - (sizeof (struct ip) + olen); 1154 bcopy(opts + olen, opts, (unsigned)i); 1155 m->m_len -= olen; 1156 if (m->m_flags & M_PKTHDR) 1157 m->m_pkthdr.len -= olen; 1158 ip->ip_vhl = IP_MAKE_VHL(IPVERSION, sizeof(struct ip) >> 2); 1159} 1160 1161u_char inetctlerrmap[PRC_NCMDS] = { 1162 0, 0, 0, 0, 1163 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, 1164 EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, 1165 EMSGSIZE, EHOSTUNREACH, 0, 0, 1166 0, 0, 0, 0, 1167 ENOPROTOOPT 1168}; 1169 1170/* 1171 * Forward a packet. If some error occurs return the sender 1172 * an icmp packet. Note we can't always generate a meaningful 1173 * icmp message because icmp doesn't have a large enough repertoire 1174 * of codes and types. 1175 * 1176 * If not forwarding, just drop the packet. This could be confusing 1177 * if ipforwarding was zero but some routing protocol was advancing 1178 * us as a gateway to somewhere. However, we must let the routing 1179 * protocol deal with that. 1180 * 1181 * The srcrt parameter indicates whether the packet is being forwarded 1182 * via a source route. 1183 */ 1184static void 1185ip_forward(m, srcrt) 1186 struct mbuf *m; 1187 int srcrt; 1188{ 1189 register struct ip *ip = mtod(m, struct ip *); 1190 register struct sockaddr_in *sin; 1191 register struct rtentry *rt; 1192 int error, type = 0, code = 0; 1193 struct mbuf *mcopy; 1194 n_long dest; 1195 struct ifnet *destifp; 1196 1197 dest = 0; 1198#ifdef DIAGNOSTIC 1199 if (ipprintfs) 1200 printf("forward: src %lx dst %lx ttl %x\n", 1201 ip->ip_src.s_addr, ip->ip_dst.s_addr, ip->ip_ttl); 1202#endif 1203 1204 1205 if (m->m_flags & M_BCAST || in_canforward(ip->ip_dst) == 0) { 1206 ipstat.ips_cantforward++; 1207 m_freem(m); 1208 return; 1209 } 1210 HTONS(ip->ip_id); 1211 if (ip->ip_ttl <= IPTTLDEC) { 1212 icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); 1213 return; 1214 } 1215 ip->ip_ttl -= IPTTLDEC; 1216 1217 sin = (struct sockaddr_in *)&ipforward_rt.ro_dst; 1218 if ((rt = ipforward_rt.ro_rt) == 0 || 1219 ip->ip_dst.s_addr != sin->sin_addr.s_addr) { 1220 if (ipforward_rt.ro_rt) { 1221 RTFREE(ipforward_rt.ro_rt); 1222 ipforward_rt.ro_rt = 0; 1223 } 1224 sin->sin_family = AF_INET; 1225 sin->sin_len = sizeof(*sin); 1226 sin->sin_addr = ip->ip_dst; 1227 1228 rtalloc_ign(&ipforward_rt, RTF_PRCLONING); 1229 if (ipforward_rt.ro_rt == 0) { 1230 icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0); 1231 return; 1232 } 1233 rt = ipforward_rt.ro_rt; 1234 } 1235 1236 /* 1237 * Save at most 64 bytes of the packet in case 1238 * we need to generate an ICMP message to the src. 1239 */ 1240 mcopy = m_copy(m, 0, imin((int)ip->ip_len, 64)); 1241 1242 /* 1243 * If forwarding packet using same interface that it came in on, 1244 * perhaps should send a redirect to sender to shortcut a hop. 1245 * Only send redirect if source is sending directly to us, 1246 * and if packet was not source routed (or has any options). 1247 * Also, don't send redirect if forwarding using a default route 1248 * or a route modified by a redirect. 1249 */ 1250#define satosin(sa) ((struct sockaddr_in *)(sa)) 1251 if (rt->rt_ifp == m->m_pkthdr.rcvif && 1252 (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && 1253 satosin(rt_key(rt))->sin_addr.s_addr != 0 && 1254 ipsendredirects && !srcrt) { 1255#define RTA(rt) ((struct in_ifaddr *)(rt->rt_ifa)) 1256 u_long src = ntohl(ip->ip_src.s_addr); 1257 1258 if (RTA(rt) && 1259 (src & RTA(rt)->ia_subnetmask) == RTA(rt)->ia_subnet) { 1260 if (rt->rt_flags & RTF_GATEWAY) 1261 dest = satosin(rt->rt_gateway)->sin_addr.s_addr; 1262 else 1263 dest = ip->ip_dst.s_addr; 1264 /* Router requirements says to only send host redirects */ 1265 type = ICMP_REDIRECT; 1266 code = ICMP_REDIRECT_HOST; 1267#ifdef DIAGNOSTIC 1268 if (ipprintfs) 1269 printf("redirect (%d) to %lx\n", code, (u_long)dest); 1270#endif 1271 } 1272 } 1273 1274 error = ip_output(m, (struct mbuf *)0, &ipforward_rt, 1275 IP_FORWARDING, 0); 1276 if (error) 1277 ipstat.ips_cantforward++; 1278 else { 1279 ipstat.ips_forward++; 1280 if (type) 1281 ipstat.ips_redirectsent++; 1282 else { 1283 if (mcopy) 1284 m_freem(mcopy); 1285 return; 1286 } 1287 } 1288 if (mcopy == NULL) 1289 return; 1290 destifp = NULL; 1291 1292 switch (error) { 1293 1294 case 0: /* forwarded, but need redirect */ 1295 /* type, code set above */ 1296 break; 1297 1298 case ENETUNREACH: /* shouldn't happen, checked above */ 1299 case EHOSTUNREACH: 1300 case ENETDOWN: 1301 case EHOSTDOWN: 1302 default: 1303 type = ICMP_UNREACH; 1304 code = ICMP_UNREACH_HOST; 1305 break; 1306 1307 case EMSGSIZE: 1308 type = ICMP_UNREACH; 1309 code = ICMP_UNREACH_NEEDFRAG; 1310 if (ipforward_rt.ro_rt) 1311 destifp = ipforward_rt.ro_rt->rt_ifp; 1312 ipstat.ips_cantfrag++; 1313 break; 1314 1315 case ENOBUFS: 1316 type = ICMP_SOURCEQUENCH; 1317 code = 0; 1318 break; 1319 } 1320 icmp_error(mcopy, type, code, dest, destifp); 1321} 1322 1323void 1324ip_savecontrol(inp, mp, ip, m) 1325 register struct inpcb *inp; 1326 register struct mbuf **mp; 1327 register struct ip *ip; 1328 register struct mbuf *m; 1329{ 1330 if (inp->inp_socket->so_options & SO_TIMESTAMP) { 1331 struct timeval tv; 1332 1333 microtime(&tv); 1334 *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), 1335 SCM_TIMESTAMP, SOL_SOCKET); 1336 if (*mp) 1337 mp = &(*mp)->m_next; 1338 } 1339 if (inp->inp_flags & INP_RECVDSTADDR) { 1340 *mp = sbcreatecontrol((caddr_t) &ip->ip_dst, 1341 sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); 1342 if (*mp) 1343 mp = &(*mp)->m_next; 1344 } 1345#ifdef notyet 1346 /* XXX 1347 * Moving these out of udp_input() made them even more broken 1348 * than they already were. 1349 */ 1350 /* options were tossed already */ 1351 if (inp->inp_flags & INP_RECVOPTS) { 1352 *mp = sbcreatecontrol((caddr_t) opts_deleted_above, 1353 sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); 1354 if (*mp) 1355 mp = &(*mp)->m_next; 1356 } 1357 /* ip_srcroute doesn't do what we want here, need to fix */ 1358 if (inp->inp_flags & INP_RECVRETOPTS) { 1359 *mp = sbcreatecontrol((caddr_t) ip_srcroute(), 1360 sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); 1361 if (*mp) 1362 mp = &(*mp)->m_next; 1363 } 1364#endif 1365 if (inp->inp_flags & INP_RECVIF) { 1366 struct sockaddr_dl sdl; 1367 1368 sdl.sdl_len = offsetof(struct sockaddr_dl, sdl_data[0]); 1369 sdl.sdl_family = AF_LINK; 1370 sdl.sdl_index = m->m_pkthdr.rcvif ? 1371 m->m_pkthdr.rcvif->if_index : 0; 1372 sdl.sdl_nlen = sdl.sdl_alen = sdl.sdl_slen = 0; 1373 *mp = sbcreatecontrol((caddr_t) &sdl, sdl.sdl_len, 1374 IP_RECVIF, IPPROTO_IP); 1375 if (*mp) 1376 mp = &(*mp)->m_next; 1377 } 1378} 1379 1380int 1381ip_rsvp_init(struct socket *so) 1382{ 1383 if (so->so_type != SOCK_RAW || 1384 so->so_proto->pr_protocol != IPPROTO_RSVP) 1385 return EOPNOTSUPP; 1386 1387 if (ip_rsvpd != NULL) 1388 return EADDRINUSE; 1389 1390 ip_rsvpd = so; 1391 /* 1392 * This may seem silly, but we need to be sure we don't over-increment 1393 * the RSVP counter, in case something slips up. 1394 */ 1395 if (!ip_rsvp_on) { 1396 ip_rsvp_on = 1; 1397 rsvp_on++; 1398 } 1399 1400 return 0; 1401} 1402 1403int 1404ip_rsvp_done(void) 1405{ 1406 ip_rsvpd = NULL; 1407 /* 1408 * This may seem silly, but we need to be sure we don't over-decrement 1409 * the RSVP counter, in case something slips up. 1410 */ 1411 if (ip_rsvp_on) { 1412 ip_rsvp_on = 0; 1413 rsvp_on--; 1414 } 1415 return 0; 1416} 1417