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1.1 ! root 1: /* ! 2: * Copyright (c) 2000 Apple Computer, Inc. All rights reserved. ! 3: * ! 4: * @APPLE_LICENSE_HEADER_START@ ! 5: * ! 6: * The contents of this file constitute Original Code as defined in and ! 7: * are subject to the Apple Public Source License Version 1.1 (the ! 8: * "License"). You may not use this file except in compliance with the ! 9: * License. Please obtain a copy of the License at ! 10: * http://www.apple.com/publicsource and read it before using this file. ! 11: * ! 12: * This Original Code and all software distributed under the License are ! 13: * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER ! 14: * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, ! 15: * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, ! 16: * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the ! 17: * License for the specific language governing rights and limitations ! 18: * under the License. ! 19: * ! 20: * @APPLE_LICENSE_HEADER_END@ ! 21: */ ! 22: /* ! 23: * Copyright (c) 1982, 1986, 1988, 1993 ! 24: * The Regents of the University of California. All rights reserved. ! 25: * ! 26: * Redistribution and use in source and binary forms, with or without ! 27: * modification, are permitted provided that the following conditions ! 28: * are met: ! 29: * 1. Redistributions of source code must retain the above copyright ! 30: * notice, this list of conditions and the following disclaimer. ! 31: * 2. Redistributions in binary form must reproduce the above copyright ! 32: * notice, this list of conditions and the following disclaimer in the ! 33: * documentation and/or other materials provided with the distribution. ! 34: * 3. All advertising materials mentioning features or use of this software ! 35: * must display the following acknowledgement: ! 36: * This product includes software developed by the University of ! 37: * California, Berkeley and its contributors. ! 38: * 4. Neither the name of the University nor the names of its contributors ! 39: * may be used to endorse or promote products derived from this software ! 40: * without specific prior written permission. ! 41: * ! 42: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND ! 43: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE ! 44: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ! 45: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE ! 46: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL ! 47: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS ! 48: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) ! 49: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT ! 50: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY ! 51: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF ! 52: * SUCH DAMAGE. ! 53: * ! 54: * @(#)ip_input.c 8.2 (Berkeley) 1/4/94 ! 55: * $ANA: ip_input.c,v 1.5 1996/09/18 14:34:59 wollman Exp $ ! 56: */ ! 57: ! 58: #define _IP_VHL ! 59: ! 60: #include <stddef.h> ! 61: ! 62: #include <sys/param.h> ! 63: #include <sys/systm.h> ! 64: #include <sys/mbuf.h> ! 65: #include <sys/malloc.h> ! 66: #include <sys/domain.h> ! 67: #include <sys/protosw.h> ! 68: #include <sys/socket.h> ! 69: #include <sys/time.h> ! 70: #include <sys/kernel.h> ! 71: #include <sys/syslog.h> ! 72: #include <sys/sysctl.h> ! 73: ! 74: #include <kern/queue.h> ! 75: ! 76: #include <net/if.h> ! 77: #include <net/if_var.h> ! 78: #include <net/if_dl.h> ! 79: #include <net/route.h> ! 80: #include <net/netisr.h> ! 81: ! 82: #include <netinet/in.h> ! 83: #include <netinet/in_systm.h> ! 84: #include <netinet/in_var.h> ! 85: #include <netinet/ip.h> ! 86: #include <netinet/in_pcb.h> ! 87: #include <netinet/ip_var.h> ! 88: #include <netinet/ip_icmp.h> ! 89: #include <sys/socketvar.h> ! 90: ! 91: #if IPFIREWALL ! 92: #include <netinet/ip_fw.h> ! 93: #endif ! 94: ! 95: #if DUMMYNET ! 96: #include <netinet/ip_dummynet.h> ! 97: #endif ! 98: ! 99: int rsvp_on = 0; ! 100: static int ip_rsvp_on; ! 101: struct socket *ip_rsvpd; ! 102: ! 103: int ipforwarding = 0; ! 104: SYSCTL_INT(_net_inet_ip, IPCTL_FORWARDING, forwarding, CTLFLAG_RW, ! 105: &ipforwarding, 0, ""); ! 106: ! 107: static int ipsendredirects = 1; /* XXX */ ! 108: SYSCTL_INT(_net_inet_ip, IPCTL_SENDREDIRECTS, redirect, CTLFLAG_RW, ! 109: &ipsendredirects, 0, ""); ! 110: ! 111: int ip_defttl = IPDEFTTL; ! 112: SYSCTL_INT(_net_inet_ip, IPCTL_DEFTTL, ttl, CTLFLAG_RW, ! 113: &ip_defttl, 0, ""); ! 114: ! 115: static int ip_dosourceroute = 0; ! 116: SYSCTL_INT(_net_inet_ip, IPCTL_SOURCEROUTE, sourceroute, CTLFLAG_RW, ! 117: &ip_dosourceroute, 0, ""); ! 118: ! 119: static int ip_acceptsourceroute = 0; ! 120: SYSCTL_INT(_net_inet_ip, IPCTL_ACCEPTSOURCEROUTE, accept_sourceroute, ! 121: CTLFLAG_RW, &ip_acceptsourceroute, 0, ""); ! 122: #if DIAGNOSTIC ! 123: static int ipprintfs = 0; ! 124: #endif ! 125: ! 126: extern struct domain inetdomain; ! 127: extern struct protosw inetsw[]; ! 128: struct protosw *ip_protox[IPPROTO_MAX]; ! 129: static int ipqmaxlen = IFQ_MAXLEN; ! 130: struct in_ifaddrhead in_ifaddrhead; /* first inet address */ ! 131: struct ifqueue ipintrq; ! 132: SYSCTL_INT(_net_inet_ip, IPCTL_INTRQMAXLEN, intr_queue_maxlen, CTLFLAG_RD, ! 133: &ipintrq.ifq_maxlen, 0, ""); ! 134: SYSCTL_INT(_net_inet_ip, IPCTL_INTRQDROPS, intr_queue_drops, CTLFLAG_RD, ! 135: &ipintrq.ifq_drops, 0, ""); ! 136: ! 137: struct ipstat ipstat; ! 138: SYSCTL_STRUCT(_net_inet_ip, IPCTL_STATS, stats, CTLFLAG_RD, ! 139: &ipstat, ipstat, ""); ! 140: ! 141: /* Packet reassembly stuff */ ! 142: #define IPREASS_NHASH_LOG2 6 ! 143: #define IPREASS_NHASH (1 << IPREASS_NHASH_LOG2) ! 144: #define IPREASS_HMASK (IPREASS_NHASH - 1) ! 145: #define IPREASS_HASH(x,y) \ ! 146: ((((x) & 0xF | ((((x) >> 8) & 0xF) << 4)) ^ (y)) & IPREASS_HMASK) ! 147: ! 148: static struct ipq ipq[IPREASS_NHASH]; ! 149: static int nipq = 0; /* total # of reass queues */ ! 150: static int maxnipq; ! 151: ! 152: #if IPCTL_DEFMTU ! 153: SYSCTL_INT(_net_inet_ip, IPCTL_DEFMTU, mtu, CTLFLAG_RW, ! 154: &ip_mtu, 0, ""); ! 155: #endif ! 156: ! 157: #if !defined(COMPAT_IPFW) || COMPAT_IPFW == 1 ! 158: #undef COMPAT_IPFW ! 159: #define COMPAT_IPFW 1 ! 160: #else ! 161: #undef COMPAT_IPFW ! 162: #endif ! 163: ! 164: #if COMPAT_IPFW ! 165: ! 166: #include <netinet/ip_fw.h> ! 167: ! 168: /* Firewall hooks */ ! 169: ip_fw_chk_t *ip_fw_chk_ptr; ! 170: ip_fw_ctl_t *ip_fw_ctl_ptr; ! 171: ! 172: #if DUMMYNET ! 173: ip_dn_ctl_t *ip_dn_ctl_ptr; ! 174: #endif ! 175: ! 176: /* IP Network Address Translation (NAT) hooks */ ! 177: ip_nat_t *ip_nat_ptr; ! 178: ip_nat_ctl_t *ip_nat_ctl_ptr; ! 179: #endif ! 180: ! 181: #if defined(IPFILTER_LKM) || defined(IPFILTER) ! 182: int iplattach __P((void)); ! 183: int (*fr_checkp) __P((struct ip *, int, struct ifnet *, int, struct mbuf **)) = NULL; ! 184: #endif ! 185: ! 186: ! 187: /* ! 188: * We need to save the IP options in case a protocol wants to respond ! 189: * to an incoming packet over the same route if the packet got here ! 190: * using IP source routing. This allows connection establishment and ! 191: * maintenance when the remote end is on a network that is not known ! 192: * to us. ! 193: */ ! 194: static int ip_nhops = 0; ! 195: static struct ip_srcrt { ! 196: struct in_addr dst; /* final destination */ ! 197: char nop; /* one NOP to align */ ! 198: char srcopt[IPOPT_OFFSET + 1]; /* OPTVAL, OLEN and OFFSET */ ! 199: struct in_addr route[MAX_IPOPTLEN/sizeof(struct in_addr)]; ! 200: } ip_srcrt; ! 201: ! 202: #if IPDIVERT ! 203: /* ! 204: * Shared variable between ip_input() and ip_reass() to communicate ! 205: * about which packets, once assembled from fragments, get diverted, ! 206: * and to which port. ! 207: */ ! 208: static u_short frag_divert_port; ! 209: #endif ! 210: ! 211: struct sockaddr_in *ip_fw_fwd_addr; ! 212: ! 213: static void save_rte __P((u_char *, struct in_addr)); ! 214: static int ip_dooptions __P((struct mbuf *)); ! 215: static void ip_forward __P((struct mbuf *, int)); ! 216: static void ip_freef __P((struct ipq *)); ! 217: static struct ip * ! 218: ip_reass __P((struct mbuf *, struct ipq *, struct ipq *)); ! 219: static struct in_ifaddr * ! 220: ip_rtaddr __P((struct in_addr)); ! 221: void ipintr __P((void)); ! 222: /* ! 223: * IP initialization: fill in IP protocol switch table. ! 224: * All protocols not implemented in kernel go to raw IP protocol handler. ! 225: */ ! 226: void ! 227: ip_init() ! 228: { ! 229: register struct protosw *pr; ! 230: register int i; ! 231: static ip_initialized = 0; ! 232: ! 233: if (!ip_initialized) ! 234: { ! 235: TAILQ_INIT(&in_ifaddrhead); ! 236: pr = pffindproto(PF_INET, IPPROTO_RAW, SOCK_RAW); ! 237: if (pr == 0) ! 238: panic("ip_init"); ! 239: for (i = 0; i < IPPROTO_MAX; i++) ! 240: ip_protox[i] = pr; ! 241: for (pr = inetdomain.dom_protosw; pr; pr = pr->pr_next) ! 242: { if(!((unsigned int)pr->pr_domain)) continue; /* If uninitialized, skip */ ! 243: if (pr->pr_domain->dom_family == PF_INET && ! 244: pr->pr_protocol && pr->pr_protocol != IPPROTO_RAW) ! 245: ip_protox[pr->pr_protocol] = pr; ! 246: } ! 247: for (i = 0; i < IPREASS_NHASH; i++) ! 248: ipq[i].next = ipq[i].prev = &ipq[i]; ! 249: ! 250: maxnipq = nmbclusters/4; ! 251: ! 252: ip_id = time_second & 0xffff; ! 253: ipintrq.ifq_maxlen = ipqmaxlen; ! 254: #if DUMMYNET ! 255: ip_dn_init(); ! 256: #endif ! 257: #if IPNAT ! 258: ip_nat_init(); ! 259: #endif ! 260: #if IPFILTER ! 261: iplattach(); ! 262: #endif ! 263: ip_initialized = 1; ! 264: } ! 265: } ! 266: ! 267: /* Initialize the PF_INET domain, and add in the pre-defined protos */ ! 268: void ! 269: in_dinit() ! 270: { register int i; ! 271: register struct protosw *pr; ! 272: register struct domain *dp; ! 273: static inetdomain_initted = 0; ! 274: extern int in_proto_count; ! 275: ! 276: if (!inetdomain_initted) ! 277: { kprintf("Initing %d protosw entries\n", in_proto_count); ! 278: dp = &inetdomain; ! 279: ! 280: for (i=0, pr = &inetsw[0]; i<in_proto_count; i++, pr++) ! 281: net_add_proto(pr, dp); ! 282: inetdomain_initted = 1; ! 283: } ! 284: } ! 285: ! 286: static struct sockaddr_in ipaddr = { sizeof(ipaddr), AF_INET }; ! 287: static struct route ipforward_rt; ! 288: ! 289: /* ! 290: * Ip input routine. Checksum and byte swap header. If fragmented ! 291: * try to reassemble. Process options. Pass to next level. ! 292: */ ! 293: void ! 294: ip_input(struct mbuf *m) ! 295: { ! 296: struct ip *ip; ! 297: struct ipq *fp; ! 298: struct in_ifaddr *ia; ! 299: int i, hlen, mff; ! 300: u_short sum; ! 301: #if !IPDIVERT /* dummy variable for the firewall code to play with */ ! 302: u_short ip_divert_cookie = 0 ; ! 303: #endif ! 304: #if COMPAT_IPFW ! 305: struct ip_fw_chain *rule = NULL ; ! 306: #endif ! 307: ! 308: #if IPFIREWALL && DUMMYNET ! 309: /* ! 310: * dummynet packet are prepended a vestigial mbuf with ! 311: * m_type = MT_DUMMYNET and m_data pointing to the matching ! 312: * rule. ! 313: */ ! 314: if (m->m_type == MT_DUMMYNET) { ! 315: struct mbuf *m0 = m ; ! 316: rule = (struct ip_fw_chain *)(m->m_data) ; ! 317: m = m->m_next ; ! 318: FREE(m0, M_IPFW); ! 319: ip = mtod(m, struct ip *); ! 320: hlen = IP_VHL_HL(ip->ip_vhl) << 2; ! 321: goto iphack ; ! 322: } else ! 323: rule = NULL ; ! 324: #endif ! 325: ! 326: #if DIAGNOSTIC ! 327: if (m == NULL || (m->m_flags & M_PKTHDR) == 0) ! 328: panic("ip_input no HDR"); ! 329: #endif ! 330: /* ! 331: * If no IP addresses have been set yet but the interfaces ! 332: * are receiving, can't do anything with incoming packets yet. ! 333: * XXX This is broken! We should be able to receive broadcasts ! 334: * and multicasts even without any local addresses configured. ! 335: */ ! 336: if (TAILQ_EMPTY(&in_ifaddrhead)) ! 337: goto bad; ! 338: ipstat.ips_total++; ! 339: ! 340: if (m->m_pkthdr.len < sizeof(struct ip)) ! 341: goto tooshort; ! 342: ! 343: if (m->m_len < sizeof (struct ip) && ! 344: (m = m_pullup(m, sizeof (struct ip))) == 0) { ! 345: ipstat.ips_toosmall++; ! 346: return; ! 347: } ! 348: ip = mtod(m, struct ip *); ! 349: ! 350: if (IP_VHL_V(ip->ip_vhl) != IPVERSION) { ! 351: ipstat.ips_badvers++; ! 352: goto bad; ! 353: } ! 354: ! 355: hlen = IP_VHL_HL(ip->ip_vhl) << 2; ! 356: if (hlen < sizeof(struct ip)) { /* minimum header length */ ! 357: ipstat.ips_badhlen++; ! 358: goto bad; ! 359: } ! 360: if (hlen > m->m_len) { ! 361: if ((m = m_pullup(m, hlen)) == 0) { ! 362: ipstat.ips_badhlen++; ! 363: return; ! 364: } ! 365: ip = mtod(m, struct ip *); ! 366: } ! 367: ! 368: sum = in_cksum(m, hlen); ! 369: ! 370: if (sum) { ! 371: ipstat.ips_badsum++; ! 372: goto bad; ! 373: } ! 374: ! 375: /* ! 376: * Convert fields to host representation. ! 377: */ ! 378: NTOHS(ip->ip_len); ! 379: if (ip->ip_len < hlen) { ! 380: ipstat.ips_badlen++; ! 381: goto bad; ! 382: } ! 383: NTOHS(ip->ip_id); ! 384: NTOHS(ip->ip_off); ! 385: ! 386: /* ! 387: * Check that the amount of data in the buffers ! 388: * is as at least much as the IP header would have us expect. ! 389: * Trim mbufs if longer than we expect. ! 390: * Drop packet if shorter than we expect. ! 391: */ ! 392: if (m->m_pkthdr.len < ip->ip_len) { ! 393: tooshort: ! 394: ipstat.ips_tooshort++; ! 395: goto bad; ! 396: } ! 397: if (m->m_pkthdr.len > ip->ip_len) { ! 398: if (m->m_len == m->m_pkthdr.len) { ! 399: m->m_len = ip->ip_len; ! 400: m->m_pkthdr.len = ip->ip_len; ! 401: } else ! 402: m_adj(m, ip->ip_len - m->m_pkthdr.len); ! 403: } ! 404: /* ! 405: * IpHack's section. ! 406: * Right now when no processing on packet has done ! 407: * and it is still fresh out of network we do our black ! 408: * deals with it. ! 409: * - Firewall: deny/allow/divert ! 410: * - Xlate: translate packet's addr/port (NAT). ! 411: * - Pipe: pass pkt through dummynet. ! 412: * - Wrap: fake packet's addr/port <unimpl.> ! 413: * - Encapsulate: put it in another IP and send out. <unimp.> ! 414: */ ! 415: ! 416: #if defined(IPFIREWALL) && defined(DUMMYNET) ! 417: iphack: ! 418: #endif ! 419: #if defined(IPFILTER) || defined(IPFILTER_LKM) ! 420: /* ! 421: * Check if we want to allow this packet to be processed. ! 422: * Consider it to be bad if not. ! 423: */ ! 424: if (fr_checkp) { ! 425: struct mbuf *m1 = m; ! 426: ! 427: if ((*fr_checkp)(ip, hlen, m->m_pkthdr.rcvif, 0, &m1) || !m1) ! 428: return; ! 429: ip = mtod(m = m1, struct ip *); ! 430: } ! 431: #endif ! 432: #if COMPAT_IPFW ! 433: if (ip_fw_chk_ptr) { ! 434: #if IPFIREWALL_FORWARD ! 435: /* ! 436: * If we've been forwarded from the output side, then ! 437: * skip the firewall a second time ! 438: */ ! 439: if (ip_fw_fwd_addr) ! 440: goto ours; ! 441: #endif /* IPFIREWALL_FORWARD */ ! 442: i = (*ip_fw_chk_ptr)(&ip, hlen, NULL, &ip_divert_cookie, ! 443: &m, &rule, &ip_fw_fwd_addr); ! 444: /* ! 445: * see the comment in ip_output for the return values ! 446: * produced by the firewall. ! 447: */ ! 448: if (!m) /* packet discarded by firewall */ ! 449: return ; ! 450: if (i == 0 && ip_fw_fwd_addr == NULL) /* common case */ ! 451: goto pass ; ! 452: #if DUMMYNET ! 453: if (i & 0x10000) { ! 454: /* send packet to the appropriate pipe */ ! 455: dummynet_io(i&0xffff,DN_TO_IP_IN,m,NULL,NULL,0, rule); ! 456: return ; ! 457: } ! 458: #endif ! 459: #if IPDIVERT ! 460: if (i > 0 && i < 0x10000) { ! 461: /* Divert packet */ ! 462: frag_divert_port = i & 0xffff ; ! 463: goto ours; ! 464: } ! 465: #endif ! 466: #if IPFIREWALL_FORWARD ! 467: if (i == 0 && ip_fw_fwd_addr != NULL) ! 468: goto pass ; ! 469: #endif ! 470: /* ! 471: * if we get here, the packet must be dropped ! 472: */ ! 473: m_freem(m); ! 474: return; ! 475: } ! 476: pass: ! 477: ! 478: if (ip_nat_ptr && !(*ip_nat_ptr)(&ip, &m, m->m_pkthdr.rcvif, IP_NAT_IN)) ! 479: return; ! 480: #endif /* !COMPAT_IPFW */ ! 481: ! 482: /* ! 483: * Process options and, if not destined for us, ! 484: * ship it on. ip_dooptions returns 1 when an ! 485: * error was detected (causing an icmp message ! 486: * to be sent and the original packet to be freed). ! 487: */ ! 488: ip_nhops = 0; /* for source routed packets */ ! 489: if (hlen > sizeof (struct ip) && ip_dooptions(m)) ! 490: return; ! 491: ! 492: /* greedy RSVP, snatches any PATH packet of the RSVP protocol and no ! 493: * matter if it is destined to another node, or whether it is ! 494: * a multicast one, RSVP wants it! and prevents it from being forwarded ! 495: * anywhere else. Also checks if the rsvp daemon is running before ! 496: * grabbing the packet. ! 497: */ ! 498: if (rsvp_on && ip->ip_p==IPPROTO_RSVP) ! 499: goto ours; ! 500: ! 501: /* ! 502: * Check our list of addresses, to see if the packet is for us. ! 503: */ ! 504: for (ia = TAILQ_FIRST(&in_ifaddrhead); ia; ! 505: ia = TAILQ_NEXT(ia, ia_link)) { ! 506: #define satosin(sa) ((struct sockaddr_in *)(sa)) ! 507: ! 508: if (IA_SIN(ia)->sin_addr.s_addr == ip->ip_dst.s_addr) ! 509: goto ours; ! 510: ! 511: if (IA_SIN(ia)->sin_addr.s_addr == INADDR_ANY) ! 512: goto ours; ! 513: ! 514: #if IPFIREWALL_FORWARD ! 515: /* ! 516: * If the addr to forward to is one of ours, we pretend to ! 517: * be the destination for this packet. ! 518: */ ! 519: if (ip_fw_fwd_addr != NULL && ! 520: IA_SIN(ia)->sin_addr.s_addr == ! 521: ip_fw_fwd_addr->sin_addr.s_addr) ! 522: goto ours; ! 523: #endif ! 524: if (ia->ia_ifp && ia->ia_ifp->if_flags & IFF_BROADCAST) { ! 525: if (satosin(&ia->ia_broadaddr)->sin_addr.s_addr == ! 526: ip->ip_dst.s_addr) ! 527: goto ours; ! 528: if (ip->ip_dst.s_addr == ia->ia_netbroadcast.s_addr) ! 529: goto ours; ! 530: } ! 531: } ! 532: if (IN_MULTICAST(ntohl(ip->ip_dst.s_addr))) { ! 533: struct in_multi *inm; ! 534: if (ip_mrouter) { ! 535: /* ! 536: * If we are acting as a multicast router, all ! 537: * incoming multicast packets are passed to the ! 538: * kernel-level multicast forwarding function. ! 539: * The packet is returned (relatively) intact; if ! 540: * ip_mforward() returns a non-zero value, the packet ! 541: * must be discarded, else it may be accepted below. ! 542: * ! 543: * (The IP ident field is put in the same byte order ! 544: * as expected when ip_mforward() is called from ! 545: * ip_output().) ! 546: */ ! 547: ip->ip_id = htons(ip->ip_id); ! 548: if (ip_mforward(ip, m->m_pkthdr.rcvif, m, 0) != 0) { ! 549: ipstat.ips_cantforward++; ! 550: m_freem(m); ! 551: return; ! 552: } ! 553: ip->ip_id = ntohs(ip->ip_id); ! 554: ! 555: /* ! 556: * The process-level routing demon needs to receive ! 557: * all multicast IGMP packets, whether or not this ! 558: * host belongs to their destination groups. ! 559: */ ! 560: if (ip->ip_p == IPPROTO_IGMP) ! 561: goto ours; ! 562: ipstat.ips_forward++; ! 563: } ! 564: /* ! 565: * See if we belong to the destination multicast group on the ! 566: * arrival interface. ! 567: */ ! 568: IN_LOOKUP_MULTI(ip->ip_dst, m->m_pkthdr.rcvif, inm); ! 569: if (inm == NULL) { ! 570: ipstat.ips_notmember++; ! 571: m_freem(m); ! 572: return; ! 573: } ! 574: goto ours; ! 575: } ! 576: if (ip->ip_dst.s_addr == (u_long)INADDR_BROADCAST) ! 577: goto ours; ! 578: if (ip->ip_dst.s_addr == INADDR_ANY) ! 579: goto ours; ! 580: ! 581: /* ! 582: * Not for us; forward if possible and desirable. ! 583: */ ! 584: if (ipforwarding == 0) { ! 585: ipstat.ips_cantforward++; ! 586: m_freem(m); ! 587: } else ! 588: ip_forward(m, 0); ! 589: return; ! 590: ! 591: ours: ! 592: ! 593: /* ! 594: * If offset or IP_MF are set, must reassemble. ! 595: * Otherwise, nothing need be done. ! 596: * (We could look in the reassembly queue to see ! 597: * if the packet was previously fragmented, ! 598: * but it's not worth the time; just let them time out.) ! 599: */ ! 600: if (ip->ip_off & (IP_MF | IP_OFFMASK | IP_RF)) { ! 601: if (m->m_flags & M_EXT) { /* XXX */ ! 602: if ((m = m_pullup(m, hlen)) == 0) { ! 603: ipstat.ips_toosmall++; ! 604: #if IPDIVERT ! 605: frag_divert_port = 0; ! 606: ip_divert_cookie = 0; ! 607: #endif ! 608: return; ! 609: } ! 610: ip = mtod(m, struct ip *); ! 611: } ! 612: sum = IPREASS_HASH(ip->ip_src.s_addr, ip->ip_id); ! 613: /* ! 614: * Look for queue of fragments ! 615: * of this datagram. ! 616: */ ! 617: for (fp = ipq[sum].next; fp != &ipq[sum]; fp = fp->next) ! 618: if (ip->ip_id == fp->ipq_id && ! 619: ip->ip_src.s_addr == fp->ipq_src.s_addr && ! 620: ip->ip_dst.s_addr == fp->ipq_dst.s_addr && ! 621: ip->ip_p == fp->ipq_p) ! 622: goto found; ! 623: ! 624: fp = 0; ! 625: ! 626: /* check if there's a place for the new queue */ ! 627: if (nipq > maxnipq) { ! 628: /* ! 629: * drop something from the tail of the current queue ! 630: * before proceeding further ! 631: */ ! 632: if (ipq[sum].prev == &ipq[sum]) { /* gak */ ! 633: for (i = 0; i < IPREASS_NHASH; i++) { ! 634: if (ipq[i].prev != &ipq[i]) { ! 635: ip_freef(ipq[i].prev); ! 636: break; ! 637: } ! 638: } ! 639: } else ! 640: ip_freef(ipq[sum].prev); ! 641: } ! 642: found: ! 643: /* ! 644: * Adjust ip_len to not reflect header, ! 645: * set ip_mff if more fragments are expected, ! 646: * convert offset of this to bytes. ! 647: */ ! 648: ip->ip_len -= hlen; ! 649: mff = (ip->ip_off & IP_MF) != 0; ! 650: if (mff) { ! 651: /* ! 652: * Make sure that fragments have a data length ! 653: * that's a non-zero multiple of 8 bytes. ! 654: */ ! 655: if (ip->ip_len == 0 || (ip->ip_len & 0x7) != 0) { ! 656: ipstat.ips_toosmall++; /* XXX */ ! 657: goto bad; ! 658: } ! 659: m->m_flags |= M_FRAG; ! 660: } ! 661: ip->ip_off <<= 3; ! 662: ! 663: /* ! 664: * If datagram marked as having more fragments ! 665: * or if this is not the first fragment, ! 666: * attempt reassembly; if it succeeds, proceed. ! 667: */ ! 668: if (mff || ip->ip_off) { ! 669: ipstat.ips_fragments++; ! 670: m->m_pkthdr.header = ip; ! 671: ip = ip_reass(m, fp, &ipq[sum]); ! 672: if (ip == 0) { ! 673: #if IPFIREWALL_FORWARD ! 674: ip_fw_fwd_addr = NULL; ! 675: #endif ! 676: return; ! 677: } ! 678: /* Get the length of the reassembled packets header */ ! 679: hlen = IP_VHL_HL(ip->ip_vhl) << 2; ! 680: ipstat.ips_reassembled++; ! 681: m = dtom(ip); ! 682: #if IPDIVERT ! 683: if (frag_divert_port) { ! 684: struct mbuf m; ! 685: m.m_next = 0; ! 686: m.m_len = hlen; ! 687: m.m_data = (char *) ip; ! 688: ip->ip_len += hlen; ! 689: HTONS(ip->ip_len); ! 690: HTONS(ip->ip_off); ! 691: HTONS(ip->ip_id); ! 692: ip->ip_sum = 0; ! 693: ip->ip_sum = in_cksum(&m, hlen); ! 694: NTOHS(ip->ip_id); ! 695: NTOHS(ip->ip_off); ! 696: NTOHS(ip->ip_len); ! 697: ip->ip_len -= hlen; ! 698: } ! 699: #endif ! 700: } else ! 701: if (fp) ! 702: ip_freef(fp); ! 703: } else ! 704: ip->ip_len -= hlen; ! 705: ! 706: #if IPDIVERT ! 707: /* ! 708: * Divert reassembled packets to the divert protocol if required ! 709: * If divert port is null then cookie should be too, ! 710: * so we shouldn't need to clear them here. Assume ip_divert does so. ! 711: */ ! 712: if (frag_divert_port) { ! 713: ipstat.ips_delivered++; ! 714: ip_divert_port = frag_divert_port; ! 715: frag_divert_port = 0; ! 716: (*ip_protox[IPPROTO_DIVERT]->pr_input)(m, hlen); ! 717: return; ! 718: } ! 719: ! 720: /* Don't let packets divert themselves */ ! 721: if (ip->ip_p == IPPROTO_DIVERT) { ! 722: ipstat.ips_noproto++; ! 723: goto bad; ! 724: } ! 725: ! 726: #endif ! 727: ! 728: /* ! 729: * Switch out to protocol's input routine. ! 730: */ ! 731: ipstat.ips_delivered++; ! 732: (*ip_protox[ip->ip_p]->pr_input)(m, hlen); ! 733: #if IPFIREWALL_FORWARD ! 734: ip_fw_fwd_addr = NULL; /* tcp needed it */ ! 735: #endif ! 736: return; ! 737: bad: ! 738: #if IPFIREWALL_FORWARD ! 739: ip_fw_fwd_addr = NULL; ! 740: #endif ! 741: m_freem(m); ! 742: } ! 743: ! 744: /* ! 745: * IP software interrupt routine - to go away sometime soon ! 746: */ ! 747: void ! 748: ipintr(void) ! 749: { ! 750: int s; ! 751: struct mbuf *m; ! 752: ! 753: while(1) { ! 754: s = splimp(); ! 755: IF_DEQUEUE(&ipintrq, m); ! 756: splx(s); ! 757: if (m == 0) ! 758: return; ! 759: ! 760: ip_input(m); ! 761: } ! 762: } ! 763: ! 764: NETISR_SET(NETISR_IP, ipintr); ! 765: ! 766: /* ! 767: * Take incoming datagram fragment and try to ! 768: * reassemble it into whole datagram. If a chain for ! 769: * reassembly of this datagram already exists, then it ! 770: * is given as fp; otherwise have to make a chain. ! 771: */ ! 772: static struct ip * ! 773: ip_reass(m, fp, where) ! 774: register struct mbuf *m; ! 775: register struct ipq *fp; ! 776: struct ipq *where; ! 777: { ! 778: struct ip *ip = mtod(m, struct ip *); ! 779: register struct mbuf *p = 0, *q, *nq; ! 780: struct mbuf *t; ! 781: int hlen = IP_VHL_HL(ip->ip_vhl) << 2; ! 782: int i, next; ! 783: ! 784: /* ! 785: * Presence of header sizes in mbufs ! 786: * would confuse code below. ! 787: */ ! 788: m->m_data += hlen; ! 789: m->m_len -= hlen; ! 790: ! 791: /* ! 792: * If first fragment to arrive, create a reassembly queue. ! 793: */ ! 794: if (fp == 0) { ! 795: if ((t = m_get(M_DONTWAIT, MT_FTABLE)) == NULL) ! 796: goto dropfrag; ! 797: fp = mtod(t, struct ipq *); ! 798: insque((void *) fp, (void *) where); ! 799: nipq++; ! 800: fp->ipq_ttl = IPFRAGTTL; ! 801: fp->ipq_p = ip->ip_p; ! 802: fp->ipq_id = ip->ip_id; ! 803: fp->ipq_src = ip->ip_src; ! 804: fp->ipq_dst = ip->ip_dst; ! 805: fp->ipq_frags = m; ! 806: m->m_nextpkt = NULL; ! 807: #if IPDIVERT ! 808: fp->ipq_divert = 0; ! 809: fp->ipq_div_cookie = 0; ! 810: #endif ! 811: goto inserted; ! 812: } ! 813: ! 814: #define GETIP(m) ((struct ip*)((m)->m_pkthdr.header)) ! 815: ! 816: /* ! 817: * Find a segment which begins after this one does. ! 818: */ ! 819: for (p = NULL, q = fp->ipq_frags; q; p = q, q = q->m_nextpkt) ! 820: if (GETIP(q)->ip_off > ip->ip_off) ! 821: break; ! 822: ! 823: /* ! 824: * If there is a preceding segment, it may provide some of ! 825: * our data already. If so, drop the data from the incoming ! 826: * segment. If it provides all of our data, drop us, otherwise ! 827: * stick new segment in the proper place. ! 828: */ ! 829: if (p) { ! 830: i = GETIP(p)->ip_off + GETIP(p)->ip_len - ip->ip_off; ! 831: if (i > 0) { ! 832: if (i >= ip->ip_len) ! 833: goto dropfrag; ! 834: m_adj(dtom(ip), i); ! 835: ip->ip_off += i; ! 836: ip->ip_len -= i; ! 837: } ! 838: m->m_nextpkt = p->m_nextpkt; ! 839: p->m_nextpkt = m; ! 840: } else { ! 841: m->m_nextpkt = fp->ipq_frags; ! 842: fp->ipq_frags = m; ! 843: } ! 844: ! 845: /* ! 846: * While we overlap succeeding segments trim them or, ! 847: * if they are completely covered, dequeue them. ! 848: */ ! 849: for (; q != NULL && ip->ip_off + ip->ip_len > GETIP(q)->ip_off; ! 850: q = nq) { ! 851: i = (ip->ip_off + ip->ip_len) - ! 852: GETIP(q)->ip_off; ! 853: if (i < GETIP(q)->ip_len) { ! 854: GETIP(q)->ip_len -= i; ! 855: GETIP(q)->ip_off += i; ! 856: m_adj(q, i); ! 857: break; ! 858: } ! 859: nq = q->m_nextpkt; ! 860: m->m_nextpkt = nq; ! 861: m_freem(q); ! 862: } ! 863: ! 864: inserted: ! 865: ! 866: #if IPDIVERT ! 867: /* ! 868: * Any fragment diverting causes the whole packet to divert ! 869: */ ! 870: if (frag_divert_port) { ! 871: fp->ipq_divert = frag_divert_port; ! 872: fp->ipq_div_cookie = ip_divert_cookie; ! 873: } ! 874: frag_divert_port = 0; ! 875: ip_divert_cookie = 0; ! 876: #endif ! 877: ! 878: /* ! 879: * Check for complete reassembly. ! 880: */ ! 881: next = 0; ! 882: for (p = NULL, q = fp->ipq_frags; q; p = q, q = q->m_nextpkt) { ! 883: if (GETIP(q)->ip_off != next) ! 884: return (0); ! 885: next += GETIP(q)->ip_len; ! 886: } ! 887: /* Make sure the last packet didn't have the IP_MF flag */ ! 888: if (p->m_flags & M_FRAG) ! 889: return (0); ! 890: ! 891: /* ! 892: * Reassembly is complete. Make sure the packet is a sane size. ! 893: */ ! 894: q = fp->ipq_frags; ! 895: ip = GETIP(q); ! 896: if (next + (IP_VHL_HL(ip->ip_vhl) << 2) > IP_MAXPACKET) { ! 897: ipstat.ips_toolong++; ! 898: ip_freef(fp); ! 899: return (0); ! 900: } ! 901: ! 902: /* ! 903: * Concatenate fragments. ! 904: */ ! 905: m = q; ! 906: t = m->m_next; ! 907: m->m_next = 0; ! 908: m_cat(m, t); ! 909: nq = q->m_nextpkt; ! 910: q->m_nextpkt = 0; ! 911: for (q = nq; q != NULL; q = nq) { ! 912: nq = q->m_nextpkt; ! 913: q->m_nextpkt = NULL; ! 914: m_cat(m, q); ! 915: } ! 916: ! 917: #if IPDIVERT ! 918: /* ! 919: * extract divert port for packet, if any ! 920: */ ! 921: frag_divert_port = fp->ipq_divert; ! 922: ip_divert_cookie = fp->ipq_div_cookie; ! 923: #endif ! 924: ! 925: /* ! 926: * Create header for new ip packet by ! 927: * modifying header of first packet; ! 928: * dequeue and discard fragment reassembly header. ! 929: * Make header visible. ! 930: */ ! 931: ip->ip_len = next; ! 932: ip->ip_src = fp->ipq_src; ! 933: ip->ip_dst = fp->ipq_dst; ! 934: remque((void *) fp); ! 935: nipq--; ! 936: (void) m_free(dtom(fp)); ! 937: m->m_len += (IP_VHL_HL(ip->ip_vhl) << 2); ! 938: m->m_data -= (IP_VHL_HL(ip->ip_vhl) << 2); ! 939: /* some debugging cruft by sklower, below, will go away soon */ ! 940: if (m->m_flags & M_PKTHDR) { /* XXX this should be done elsewhere */ ! 941: register int plen = 0; ! 942: for (t = m; m; m = m->m_next) ! 943: plen += m->m_len; ! 944: t->m_pkthdr.len = plen; ! 945: } ! 946: return (ip); ! 947: ! 948: dropfrag: ! 949: #if IPDIVERT ! 950: frag_divert_port = 0; ! 951: ip_divert_cookie = 0; ! 952: #endif ! 953: ipstat.ips_fragdropped++; ! 954: m_freem(m); ! 955: return (0); ! 956: ! 957: #undef GETIP ! 958: } ! 959: ! 960: /* ! 961: * Free a fragment reassembly header and all ! 962: * associated datagrams. ! 963: */ ! 964: static void ! 965: ip_freef(fp) ! 966: struct ipq *fp; ! 967: { ! 968: register struct mbuf *q; ! 969: ! 970: while (fp->ipq_frags) { ! 971: q = fp->ipq_frags; ! 972: fp->ipq_frags = q->m_nextpkt; ! 973: m_freem(q); ! 974: } ! 975: remque((void *) fp); ! 976: (void) m_free(dtom(fp)); ! 977: nipq--; ! 978: } ! 979: ! 980: /* ! 981: * IP timer processing; ! 982: * if a timer expires on a reassembly ! 983: * queue, discard it. ! 984: */ ! 985: void ! 986: ip_slowtimo() ! 987: { ! 988: register struct ipq *fp; ! 989: int s = splnet(); ! 990: int i; ! 991: ! 992: for (i = 0; i < IPREASS_NHASH; i++) { ! 993: fp = ipq[i].next; ! 994: if (fp == 0) ! 995: continue; ! 996: while (fp != &ipq[i]) { ! 997: --fp->ipq_ttl; ! 998: fp = fp->next; ! 999: if (fp->prev->ipq_ttl == 0) { ! 1000: ipstat.ips_fragtimeout++; ! 1001: ip_freef(fp->prev); ! 1002: } ! 1003: } ! 1004: } ! 1005: ipflow_slowtimo(); ! 1006: splx(s); ! 1007: } ! 1008: ! 1009: /* ! 1010: * Drain off all datagram fragments. ! 1011: */ ! 1012: void ! 1013: ip_drain() ! 1014: { ! 1015: int i; ! 1016: ! 1017: for (i = 0; i < IPREASS_NHASH; i++) { ! 1018: while (ipq[i].next != &ipq[i]) { ! 1019: ipstat.ips_fragdropped++; ! 1020: ip_freef(ipq[i].next); ! 1021: } ! 1022: } ! 1023: in_rtqdrain(); ! 1024: } ! 1025: ! 1026: /* ! 1027: * Do option processing on a datagram, ! 1028: * possibly discarding it if bad options are encountered, ! 1029: * or forwarding it if source-routed. ! 1030: * Returns 1 if packet has been forwarded/freed, ! 1031: * 0 if the packet should be processed further. ! 1032: */ ! 1033: static int ! 1034: ip_dooptions(m) ! 1035: struct mbuf *m; ! 1036: { ! 1037: register struct ip *ip = mtod(m, struct ip *); ! 1038: register u_char *cp; ! 1039: register struct ip_timestamp *ipt; ! 1040: register struct in_ifaddr *ia; ! 1041: int opt, optlen, cnt, off, code, type = ICMP_PARAMPROB, forward = 0; ! 1042: struct in_addr *sin, dst; ! 1043: n_time ntime; ! 1044: ! 1045: dst = ip->ip_dst; ! 1046: cp = (u_char *)(ip + 1); ! 1047: cnt = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof (struct ip); ! 1048: for (; cnt > 0; cnt -= optlen, cp += optlen) { ! 1049: opt = cp[IPOPT_OPTVAL]; ! 1050: if (opt == IPOPT_EOL) ! 1051: break; ! 1052: if (opt == IPOPT_NOP) ! 1053: optlen = 1; ! 1054: else { ! 1055: optlen = cp[IPOPT_OLEN]; ! 1056: if (optlen <= 0 || optlen > cnt) { ! 1057: code = &cp[IPOPT_OLEN] - (u_char *)ip; ! 1058: goto bad; ! 1059: } ! 1060: } ! 1061: switch (opt) { ! 1062: ! 1063: default: ! 1064: break; ! 1065: ! 1066: /* ! 1067: * Source routing with record. ! 1068: * Find interface with current destination address. ! 1069: * If none on this machine then drop if strictly routed, ! 1070: * or do nothing if loosely routed. ! 1071: * Record interface address and bring up next address ! 1072: * component. If strictly routed make sure next ! 1073: * address is on directly accessible net. ! 1074: */ ! 1075: case IPOPT_LSRR: ! 1076: case IPOPT_SSRR: ! 1077: if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { ! 1078: code = &cp[IPOPT_OFFSET] - (u_char *)ip; ! 1079: goto bad; ! 1080: } ! 1081: ipaddr.sin_addr = ip->ip_dst; ! 1082: ia = (struct in_ifaddr *) ! 1083: ifa_ifwithaddr((struct sockaddr *)&ipaddr); ! 1084: if (ia == 0) { ! 1085: if (opt == IPOPT_SSRR) { ! 1086: type = ICMP_UNREACH; ! 1087: code = ICMP_UNREACH_SRCFAIL; ! 1088: goto bad; ! 1089: } ! 1090: if (!ip_dosourceroute) ! 1091: goto nosourcerouting; ! 1092: /* ! 1093: * Loose routing, and not at next destination ! 1094: * yet; nothing to do except forward. ! 1095: */ ! 1096: break; ! 1097: } ! 1098: off--; /* 0 origin */ ! 1099: if (off > optlen - sizeof(struct in_addr)) { ! 1100: /* ! 1101: * End of source route. Should be for us. ! 1102: */ ! 1103: if (!ip_acceptsourceroute) ! 1104: goto nosourcerouting; ! 1105: save_rte(cp, ip->ip_src); ! 1106: break; ! 1107: } ! 1108: ! 1109: if (!ip_dosourceroute) { ! 1110: if (ipforwarding) { ! 1111: char buf[16]; /* aaa.bbb.ccc.ddd\0 */ ! 1112: /* ! 1113: * Acting as a router, so generate ICMP ! 1114: */ ! 1115: nosourcerouting: ! 1116: strcpy(buf, inet_ntoa(ip->ip_dst)); ! 1117: log(LOG_WARNING, ! 1118: "attempted source route from %s to %s\n", ! 1119: inet_ntoa(ip->ip_src), buf); ! 1120: type = ICMP_UNREACH; ! 1121: code = ICMP_UNREACH_SRCFAIL; ! 1122: goto bad; ! 1123: } else { ! 1124: /* ! 1125: * Not acting as a router, so silently drop. ! 1126: */ ! 1127: ipstat.ips_cantforward++; ! 1128: m_freem(m); ! 1129: return (1); ! 1130: } ! 1131: } ! 1132: ! 1133: /* ! 1134: * locate outgoing interface ! 1135: */ ! 1136: (void)memcpy(&ipaddr.sin_addr, cp + off, ! 1137: sizeof(ipaddr.sin_addr)); ! 1138: ! 1139: if (opt == IPOPT_SSRR) { ! 1140: #define INA struct in_ifaddr * ! 1141: #define SA struct sockaddr * ! 1142: if ((ia = (INA)ifa_ifwithdstaddr((SA)&ipaddr)) == 0) ! 1143: ia = (INA)ifa_ifwithnet((SA)&ipaddr); ! 1144: } else ! 1145: ia = ip_rtaddr(ipaddr.sin_addr); ! 1146: if (ia == 0) { ! 1147: type = ICMP_UNREACH; ! 1148: code = ICMP_UNREACH_SRCFAIL; ! 1149: goto bad; ! 1150: } ! 1151: ip->ip_dst = ipaddr.sin_addr; ! 1152: (void)memcpy(cp + off, &(IA_SIN(ia)->sin_addr), ! 1153: sizeof(struct in_addr)); ! 1154: cp[IPOPT_OFFSET] += sizeof(struct in_addr); ! 1155: /* ! 1156: * Let ip_intr's mcast routing check handle mcast pkts ! 1157: */ ! 1158: forward = !IN_MULTICAST(ntohl(ip->ip_dst.s_addr)); ! 1159: break; ! 1160: ! 1161: case IPOPT_RR: ! 1162: if ((off = cp[IPOPT_OFFSET]) < IPOPT_MINOFF) { ! 1163: code = &cp[IPOPT_OFFSET] - (u_char *)ip; ! 1164: goto bad; ! 1165: } ! 1166: /* ! 1167: * If no space remains, ignore. ! 1168: */ ! 1169: off--; /* 0 origin */ ! 1170: if (off > optlen - sizeof(struct in_addr)) ! 1171: break; ! 1172: (void)memcpy(&ipaddr.sin_addr, &ip->ip_dst, ! 1173: sizeof(ipaddr.sin_addr)); ! 1174: /* ! 1175: * locate outgoing interface; if we're the destination, ! 1176: * use the incoming interface (should be same). ! 1177: */ ! 1178: if ((ia = (INA)ifa_ifwithaddr((SA)&ipaddr)) == 0 && ! 1179: (ia = ip_rtaddr(ipaddr.sin_addr)) == 0) { ! 1180: type = ICMP_UNREACH; ! 1181: code = ICMP_UNREACH_HOST; ! 1182: goto bad; ! 1183: } ! 1184: (void)memcpy(cp + off, &(IA_SIN(ia)->sin_addr), ! 1185: sizeof(struct in_addr)); ! 1186: cp[IPOPT_OFFSET] += sizeof(struct in_addr); ! 1187: break; ! 1188: ! 1189: case IPOPT_TS: ! 1190: code = cp - (u_char *)ip; ! 1191: ipt = (struct ip_timestamp *)cp; ! 1192: if (ipt->ipt_len < 5) ! 1193: goto bad; ! 1194: if (ipt->ipt_ptr > ipt->ipt_len - sizeof(int32_t)) { ! 1195: if (++ipt->ipt_oflw == 0) ! 1196: goto bad; ! 1197: break; ! 1198: } ! 1199: sin = (struct in_addr *)(cp + ipt->ipt_ptr - 1); ! 1200: switch (ipt->ipt_flg) { ! 1201: ! 1202: case IPOPT_TS_TSONLY: ! 1203: break; ! 1204: ! 1205: case IPOPT_TS_TSANDADDR: ! 1206: if (ipt->ipt_ptr - 1 + sizeof(n_time) + ! 1207: sizeof(struct in_addr) > ipt->ipt_len) ! 1208: goto bad; ! 1209: ipaddr.sin_addr = dst; ! 1210: ia = (INA)ifaof_ifpforaddr((SA)&ipaddr, ! 1211: m->m_pkthdr.rcvif); ! 1212: if (ia == 0) ! 1213: continue; ! 1214: (void)memcpy(sin, &IA_SIN(ia)->sin_addr, ! 1215: sizeof(struct in_addr)); ! 1216: ipt->ipt_ptr += sizeof(struct in_addr); ! 1217: break; ! 1218: ! 1219: case IPOPT_TS_PRESPEC: ! 1220: if (ipt->ipt_ptr - 1 + sizeof(n_time) + ! 1221: sizeof(struct in_addr) > ipt->ipt_len) ! 1222: goto bad; ! 1223: (void)memcpy(&ipaddr.sin_addr, sin, ! 1224: sizeof(struct in_addr)); ! 1225: if (ifa_ifwithaddr((SA)&ipaddr) == 0) ! 1226: continue; ! 1227: ipt->ipt_ptr += sizeof(struct in_addr); ! 1228: break; ! 1229: ! 1230: default: ! 1231: goto bad; ! 1232: } ! 1233: ntime = iptime(); ! 1234: (void)memcpy(cp + ipt->ipt_ptr - 1, &ntime, ! 1235: sizeof(n_time)); ! 1236: ipt->ipt_ptr += sizeof(n_time); ! 1237: } ! 1238: } ! 1239: if (forward && ipforwarding) { ! 1240: ip_forward(m, 1); ! 1241: return (1); ! 1242: } ! 1243: return (0); ! 1244: bad: ! 1245: ip->ip_len -= IP_VHL_HL(ip->ip_vhl) << 2; /* XXX icmp_error adds in hdr length */ ! 1246: icmp_error(m, type, code, 0, 0); ! 1247: ipstat.ips_badoptions++; ! 1248: return (1); ! 1249: } ! 1250: ! 1251: /* ! 1252: * Given address of next destination (final or next hop), ! 1253: * return internet address info of interface to be used to get there. ! 1254: */ ! 1255: static struct in_ifaddr * ! 1256: ip_rtaddr(dst) ! 1257: struct in_addr dst; ! 1258: { ! 1259: register struct sockaddr_in *sin; ! 1260: ! 1261: sin = (struct sockaddr_in *) &ipforward_rt.ro_dst; ! 1262: ! 1263: if (ipforward_rt.ro_rt == 0 || dst.s_addr != sin->sin_addr.s_addr) { ! 1264: if (ipforward_rt.ro_rt) { ! 1265: RTFREE(ipforward_rt.ro_rt); ! 1266: ipforward_rt.ro_rt = 0; ! 1267: } ! 1268: sin->sin_family = AF_INET; ! 1269: sin->sin_len = sizeof(*sin); ! 1270: sin->sin_addr = dst; ! 1271: ! 1272: rtalloc_ign(&ipforward_rt, RTF_PRCLONING); ! 1273: } ! 1274: if (ipforward_rt.ro_rt == 0) ! 1275: return ((struct in_ifaddr *)0); ! 1276: return ((struct in_ifaddr *) ipforward_rt.ro_rt->rt_ifa); ! 1277: } ! 1278: ! 1279: /* ! 1280: * Save incoming source route for use in replies, ! 1281: * to be picked up later by ip_srcroute if the receiver is interested. ! 1282: */ ! 1283: void ! 1284: save_rte(option, dst) ! 1285: u_char *option; ! 1286: struct in_addr dst; ! 1287: { ! 1288: unsigned olen; ! 1289: ! 1290: olen = option[IPOPT_OLEN]; ! 1291: #if DIAGNOSTIC ! 1292: if (ipprintfs) ! 1293: printf("save_rte: olen %d\n", olen); ! 1294: #endif ! 1295: if (olen > sizeof(ip_srcrt) - (1 + sizeof(dst))) ! 1296: return; ! 1297: bcopy(option, ip_srcrt.srcopt, olen); ! 1298: ip_nhops = (olen - IPOPT_OFFSET - 1) / sizeof(struct in_addr); ! 1299: ip_srcrt.dst = dst; ! 1300: } ! 1301: ! 1302: /* ! 1303: * Retrieve incoming source route for use in replies, ! 1304: * in the same form used by setsockopt. ! 1305: * The first hop is placed before the options, will be removed later. ! 1306: */ ! 1307: struct mbuf * ! 1308: ip_srcroute() ! 1309: { ! 1310: register struct in_addr *p, *q; ! 1311: register struct mbuf *m; ! 1312: ! 1313: if (ip_nhops == 0) ! 1314: return ((struct mbuf *)0); ! 1315: m = m_get(M_DONTWAIT, MT_HEADER); ! 1316: if (m == 0) ! 1317: return ((struct mbuf *)0); ! 1318: ! 1319: #define OPTSIZ (sizeof(ip_srcrt.nop) + sizeof(ip_srcrt.srcopt)) ! 1320: ! 1321: /* length is (nhops+1)*sizeof(addr) + sizeof(nop + srcrt header) */ ! 1322: m->m_len = ip_nhops * sizeof(struct in_addr) + sizeof(struct in_addr) + ! 1323: OPTSIZ; ! 1324: #if DIAGNOSTIC ! 1325: if (ipprintfs) ! 1326: printf("ip_srcroute: nhops %d mlen %d", ip_nhops, m->m_len); ! 1327: #endif ! 1328: ! 1329: /* ! 1330: * First save first hop for return route ! 1331: */ ! 1332: p = &ip_srcrt.route[ip_nhops - 1]; ! 1333: *(mtod(m, struct in_addr *)) = *p--; ! 1334: #if DIAGNOSTIC ! 1335: if (ipprintfs) ! 1336: printf(" hops %lx", (u_long)ntohl(mtod(m, struct in_addr *)->s_addr)); ! 1337: #endif ! 1338: ! 1339: /* ! 1340: * Copy option fields and padding (nop) to mbuf. ! 1341: */ ! 1342: ip_srcrt.nop = IPOPT_NOP; ! 1343: ip_srcrt.srcopt[IPOPT_OFFSET] = IPOPT_MINOFF; ! 1344: (void)memcpy(mtod(m, caddr_t) + sizeof(struct in_addr), ! 1345: &ip_srcrt.nop, OPTSIZ); ! 1346: q = (struct in_addr *)(mtod(m, caddr_t) + ! 1347: sizeof(struct in_addr) + OPTSIZ); ! 1348: #undef OPTSIZ ! 1349: /* ! 1350: * Record return path as an IP source route, ! 1351: * reversing the path (pointers are now aligned). ! 1352: */ ! 1353: while (p >= ip_srcrt.route) { ! 1354: #if DIAGNOSTIC ! 1355: if (ipprintfs) ! 1356: printf(" %lx", (u_long)ntohl(q->s_addr)); ! 1357: #endif ! 1358: *q++ = *p--; ! 1359: } ! 1360: /* ! 1361: * Last hop goes to final destination. ! 1362: */ ! 1363: *q = ip_srcrt.dst; ! 1364: #if DIAGNOSTIC ! 1365: if (ipprintfs) ! 1366: printf(" %lx\n", (u_long)ntohl(q->s_addr)); ! 1367: #endif ! 1368: return (m); ! 1369: } ! 1370: ! 1371: /* ! 1372: * Strip out IP options, at higher ! 1373: * level protocol in the kernel. ! 1374: * Second argument is buffer to which options ! 1375: * will be moved, and return value is their length. ! 1376: * XXX should be deleted; last arg currently ignored. ! 1377: */ ! 1378: void ! 1379: ip_stripoptions(m, mopt) ! 1380: register struct mbuf *m; ! 1381: struct mbuf *mopt; ! 1382: { ! 1383: register int i; ! 1384: struct ip *ip = mtod(m, struct ip *); ! 1385: register caddr_t opts; ! 1386: int olen; ! 1387: ! 1388: olen = (IP_VHL_HL(ip->ip_vhl) << 2) - sizeof (struct ip); ! 1389: opts = (caddr_t)(ip + 1); ! 1390: i = m->m_len - (sizeof (struct ip) + olen); ! 1391: bcopy(opts + olen, opts, (unsigned)i); ! 1392: m->m_len -= olen; ! 1393: if (m->m_flags & M_PKTHDR) ! 1394: m->m_pkthdr.len -= olen; ! 1395: ip->ip_vhl = IP_MAKE_VHL(IPVERSION, sizeof(struct ip) >> 2); ! 1396: } ! 1397: ! 1398: u_char inetctlerrmap[PRC_NCMDS] = { ! 1399: 0, 0, 0, 0, ! 1400: 0, EMSGSIZE, EHOSTDOWN, EHOSTUNREACH, ! 1401: EHOSTUNREACH, EHOSTUNREACH, ECONNREFUSED, ECONNREFUSED, ! 1402: EMSGSIZE, EHOSTUNREACH, 0, 0, ! 1403: 0, 0, 0, 0, ! 1404: ENOPROTOOPT ! 1405: }; ! 1406: ! 1407: /* ! 1408: * Forward a packet. If some error occurs return the sender ! 1409: * an icmp packet. Note we can't always generate a meaningful ! 1410: * icmp message because icmp doesn't have a large enough repertoire ! 1411: * of codes and types. ! 1412: * ! 1413: * If not forwarding, just drop the packet. This could be confusing ! 1414: * if ipforwarding was zero but some routing protocol was advancing ! 1415: * us as a gateway to somewhere. However, we must let the routing ! 1416: * protocol deal with that. ! 1417: * ! 1418: * The srcrt parameter indicates whether the packet is being forwarded ! 1419: * via a source route. ! 1420: */ ! 1421: static void ! 1422: ip_forward(m, srcrt) ! 1423: struct mbuf *m; ! 1424: int srcrt; ! 1425: { ! 1426: register struct ip *ip = mtod(m, struct ip *); ! 1427: register struct sockaddr_in *sin; ! 1428: register struct rtentry *rt; ! 1429: int error, type = 0, code = 0; ! 1430: struct mbuf *mcopy; ! 1431: n_long dest; ! 1432: struct ifnet *destifp; ! 1433: ! 1434: dest = 0; ! 1435: #if DIAGNOSTIC ! 1436: if (ipprintfs) ! 1437: printf("forward: src %lx dst %lx ttl %x\n", ! 1438: (u_long)ip->ip_src.s_addr, (u_long)ip->ip_dst.s_addr, ! 1439: ip->ip_ttl); ! 1440: #endif ! 1441: ! 1442: ! 1443: if (m->m_flags & M_BCAST || in_canforward(ip->ip_dst) == 0) { ! 1444: ipstat.ips_cantforward++; ! 1445: m_freem(m); ! 1446: return; ! 1447: } ! 1448: HTONS(ip->ip_id); ! 1449: if (ip->ip_ttl <= IPTTLDEC) { ! 1450: icmp_error(m, ICMP_TIMXCEED, ICMP_TIMXCEED_INTRANS, dest, 0); ! 1451: return; ! 1452: } ! 1453: ip->ip_ttl -= IPTTLDEC; ! 1454: ! 1455: sin = (struct sockaddr_in *)&ipforward_rt.ro_dst; ! 1456: if ((rt = ipforward_rt.ro_rt) == 0 || ! 1457: ip->ip_dst.s_addr != sin->sin_addr.s_addr) { ! 1458: if (ipforward_rt.ro_rt) { ! 1459: RTFREE(ipforward_rt.ro_rt); ! 1460: ipforward_rt.ro_rt = 0; ! 1461: } ! 1462: sin->sin_family = AF_INET; ! 1463: sin->sin_len = sizeof(*sin); ! 1464: sin->sin_addr = ip->ip_dst; ! 1465: ! 1466: rtalloc_ign(&ipforward_rt, RTF_PRCLONING); ! 1467: if (ipforward_rt.ro_rt == 0) { ! 1468: icmp_error(m, ICMP_UNREACH, ICMP_UNREACH_HOST, dest, 0); ! 1469: return; ! 1470: } ! 1471: rt = ipforward_rt.ro_rt; ! 1472: } ! 1473: ! 1474: /* ! 1475: * Save at most 64 bytes of the packet in case ! 1476: * we need to generate an ICMP message to the src. ! 1477: */ ! 1478: mcopy = m_copy(m, 0, imin((int)ip->ip_len, 64)); ! 1479: ! 1480: /* ! 1481: * If forwarding packet using same interface that it came in on, ! 1482: * perhaps should send a redirect to sender to shortcut a hop. ! 1483: * Only send redirect if source is sending directly to us, ! 1484: * and if packet was not source routed (or has any options). ! 1485: * Also, don't send redirect if forwarding using a default route ! 1486: * or a route modified by a redirect. ! 1487: */ ! 1488: #define satosin(sa) ((struct sockaddr_in *)(sa)) ! 1489: if (rt->rt_ifp == m->m_pkthdr.rcvif && ! 1490: (rt->rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) == 0 && ! 1491: satosin(rt_key(rt))->sin_addr.s_addr != 0 && ! 1492: ipsendredirects && !srcrt) { ! 1493: #define RTA(rt) ((struct in_ifaddr *)(rt->rt_ifa)) ! 1494: u_long src = ntohl(ip->ip_src.s_addr); ! 1495: ! 1496: if (RTA(rt) && ! 1497: (src & RTA(rt)->ia_subnetmask) == RTA(rt)->ia_subnet) { ! 1498: if (rt->rt_flags & RTF_GATEWAY) ! 1499: dest = satosin(rt->rt_gateway)->sin_addr.s_addr; ! 1500: else ! 1501: dest = ip->ip_dst.s_addr; ! 1502: /* Router requirements says to only send host redirects */ ! 1503: type = ICMP_REDIRECT; ! 1504: code = ICMP_REDIRECT_HOST; ! 1505: #if DIAGNOSTIC ! 1506: if (ipprintfs) ! 1507: printf("redirect (%d) to %lx\n", code, (u_long)dest); ! 1508: #endif ! 1509: } ! 1510: } ! 1511: ! 1512: error = ip_output(m, (struct mbuf *)0, &ipforward_rt, ! 1513: IP_FORWARDING, 0); ! 1514: if (error) ! 1515: ipstat.ips_cantforward++; ! 1516: else { ! 1517: ipstat.ips_forward++; ! 1518: if (type) ! 1519: ipstat.ips_redirectsent++; ! 1520: else { ! 1521: if (mcopy) { ! 1522: ipflow_create(&ipforward_rt, mcopy); ! 1523: m_freem(mcopy); ! 1524: } ! 1525: return; ! 1526: } ! 1527: } ! 1528: if (mcopy == NULL) ! 1529: return; ! 1530: destifp = NULL; ! 1531: ! 1532: switch (error) { ! 1533: ! 1534: case 0: /* forwarded, but need redirect */ ! 1535: /* type, code set above */ ! 1536: break; ! 1537: ! 1538: case ENETUNREACH: /* shouldn't happen, checked above */ ! 1539: case EHOSTUNREACH: ! 1540: case ENETDOWN: ! 1541: case EHOSTDOWN: ! 1542: default: ! 1543: type = ICMP_UNREACH; ! 1544: code = ICMP_UNREACH_HOST; ! 1545: break; ! 1546: ! 1547: case EMSGSIZE: ! 1548: type = ICMP_UNREACH; ! 1549: code = ICMP_UNREACH_NEEDFRAG; ! 1550: if (ipforward_rt.ro_rt) ! 1551: destifp = ipforward_rt.ro_rt->rt_ifp; ! 1552: ipstat.ips_cantfrag++; ! 1553: break; ! 1554: ! 1555: case ENOBUFS: ! 1556: type = ICMP_SOURCEQUENCH; ! 1557: code = 0; ! 1558: break; ! 1559: } ! 1560: icmp_error(mcopy, type, code, dest, destifp); ! 1561: } ! 1562: ! 1563: void ! 1564: ip_savecontrol(inp, mp, ip, m) ! 1565: register struct inpcb *inp; ! 1566: register struct mbuf **mp; ! 1567: register struct ip *ip; ! 1568: register struct mbuf *m; ! 1569: { ! 1570: if (inp->inp_socket->so_options & SO_TIMESTAMP) { ! 1571: struct timeval tv; ! 1572: ! 1573: microtime(&tv); ! 1574: *mp = sbcreatecontrol((caddr_t) &tv, sizeof(tv), ! 1575: SCM_TIMESTAMP, SOL_SOCKET); ! 1576: if (*mp) ! 1577: mp = &(*mp)->m_next; ! 1578: } ! 1579: if (inp->inp_flags & INP_RECVDSTADDR) { ! 1580: *mp = sbcreatecontrol((caddr_t) &ip->ip_dst, ! 1581: sizeof(struct in_addr), IP_RECVDSTADDR, IPPROTO_IP); ! 1582: if (*mp) ! 1583: mp = &(*mp)->m_next; ! 1584: } ! 1585: #ifdef notyet ! 1586: /* XXX ! 1587: * Moving these out of udp_input() made them even more broken ! 1588: * than they already were. ! 1589: */ ! 1590: /* options were tossed already */ ! 1591: if (inp->inp_flags & INP_RECVOPTS) { ! 1592: *mp = sbcreatecontrol((caddr_t) opts_deleted_above, ! 1593: sizeof(struct in_addr), IP_RECVOPTS, IPPROTO_IP); ! 1594: if (*mp) ! 1595: mp = &(*mp)->m_next; ! 1596: } ! 1597: /* ip_srcroute doesn't do what we want here, need to fix */ ! 1598: if (inp->inp_flags & INP_RECVRETOPTS) { ! 1599: *mp = sbcreatecontrol((caddr_t) ip_srcroute(), ! 1600: sizeof(struct in_addr), IP_RECVRETOPTS, IPPROTO_IP); ! 1601: if (*mp) ! 1602: mp = &(*mp)->m_next; ! 1603: } ! 1604: #endif ! 1605: if (inp->inp_flags & INP_RECVIF) { ! 1606: struct ifnet *ifp; ! 1607: struct sdlbuf { ! 1608: struct sockaddr_dl sdl; ! 1609: u_char pad[32]; ! 1610: } sdlbuf; ! 1611: struct sockaddr_dl *sdp; ! 1612: struct sockaddr_dl *sdl2 = &sdlbuf.sdl; ! 1613: ! 1614: if (((ifp = m->m_pkthdr.rcvif)) ! 1615: && ( ifp->if_index && (ifp->if_index <= if_index))) { ! 1616: sdp = (struct sockaddr_dl *)(ifnet_addrs ! 1617: [ifp->if_index - 1]->ifa_addr); ! 1618: /* ! 1619: * Change our mind and don't try copy. ! 1620: */ ! 1621: if ((sdp->sdl_family != AF_LINK) ! 1622: || (sdp->sdl_len > sizeof(sdlbuf))) { ! 1623: goto makedummy; ! 1624: } ! 1625: bcopy(sdp, sdl2, sdp->sdl_len); ! 1626: } else { ! 1627: makedummy: ! 1628: sdl2->sdl_len ! 1629: = offsetof(struct sockaddr_dl, sdl_data[0]); ! 1630: sdl2->sdl_family = AF_LINK; ! 1631: sdl2->sdl_index = 0; ! 1632: sdl2->sdl_nlen = sdl2->sdl_alen = sdl2->sdl_slen = 0; ! 1633: } ! 1634: *mp = sbcreatecontrol((caddr_t) sdl2, sdl2->sdl_len, ! 1635: IP_RECVIF, IPPROTO_IP); ! 1636: if (*mp) ! 1637: mp = &(*mp)->m_next; ! 1638: } ! 1639: } ! 1640: ! 1641: int ! 1642: ip_rsvp_init(struct socket *so) ! 1643: { ! 1644: if (so->so_type != SOCK_RAW || ! 1645: so->so_proto->pr_protocol != IPPROTO_RSVP) ! 1646: return EOPNOTSUPP; ! 1647: ! 1648: if (ip_rsvpd != NULL) ! 1649: return EADDRINUSE; ! 1650: ! 1651: ip_rsvpd = so; ! 1652: /* ! 1653: * This may seem silly, but we need to be sure we don't over-increment ! 1654: * the RSVP counter, in case something slips up. ! 1655: */ ! 1656: if (!ip_rsvp_on) { ! 1657: ip_rsvp_on = 1; ! 1658: rsvp_on++; ! 1659: } ! 1660: ! 1661: return 0; ! 1662: } ! 1663: ! 1664: int ! 1665: ip_rsvp_done(void) ! 1666: { ! 1667: ip_rsvpd = NULL; ! 1668: /* ! 1669: * This may seem silly, but we need to be sure we don't over-decrement ! 1670: * the RSVP counter, in case something slips up. ! 1671: */ ! 1672: if (ip_rsvp_on) { ! 1673: ip_rsvp_on = 0; ! 1674: rsvp_on--; ! 1675: } ! 1676: return 0; ! 1677: }
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