savefile.c revision 146768
1/* 2 * Copyright (c) 1993, 1994, 1995, 1996, 1997 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: (1) source code distributions 7 * retain the above copyright notice and this paragraph in its entirety, (2) 8 * distributions including binary code include the above copyright notice and 9 * this paragraph in its entirety in the documentation or other materials 10 * provided with the distribution, and (3) all advertising materials mentioning 11 * features or use of this software display the following acknowledgement: 12 * ``This product includes software developed by the University of California, 13 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of 14 * the University nor the names of its contributors may be used to endorse 15 * or promote products derived from this software without specific prior 16 * written permission. 17 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED 18 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF 19 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. 20 * 21 * savefile.c - supports offline use of tcpdump 22 * Extraction/creation by Jeffrey Mogul, DECWRL 23 * Modified by Steve McCanne, LBL. 24 * 25 * Used to save the received packet headers, after filtering, to 26 * a file, and then read them later. 27 * The first record in the file contains saved values for the machine 28 * dependent values so we can print the dump file on any architecture. 29 */ 30 31#ifndef lint 32static const char rcsid[] _U_ = 33 "@(#) $Header: /tcpdump/master/libpcap/savefile.c,v 1.126 2005/02/08 20:03:16 guy Exp $ (LBL)"; 34#endif 35 36#ifdef HAVE_CONFIG_H 37#include "config.h" 38#endif 39 40#include <errno.h> 41#include <memory.h> 42#include <stdio.h> 43#include <stdlib.h> 44#include <string.h> 45 46#include "pcap-int.h" 47 48#ifdef HAVE_OS_PROTO_H 49#include "os-proto.h" 50#endif 51 52/* 53 * Standard libpcap format. 54 */ 55#define TCPDUMP_MAGIC 0xa1b2c3d4 56 57/* 58 * Alexey Kuznetzov's modified libpcap format. 59 */ 60#define KUZNETZOV_TCPDUMP_MAGIC 0xa1b2cd34 61 62/* 63 * Reserved for Francisco Mesquita <francisco.mesquita@radiomovel.pt> 64 * for another modified format. 65 */ 66#define FMESQUITA_TCPDUMP_MAGIC 0xa1b234cd 67 68/* 69 * Navtel Communcations' format, with nanosecond timestamps, 70 * as per a request from Dumas Hwang <dumas.hwang@navtelcom.com>. 71 */ 72#define NAVTEL_TCPDUMP_MAGIC 0xa12b3c4d 73 74/* 75 * We use the "receiver-makes-right" approach to byte order, 76 * because time is at a premium when we are writing the file. 77 * In other words, the pcap_file_header and pcap_pkthdr, 78 * records are written in host byte order. 79 * Note that the bytes of packet data are written out in the order in 80 * which they were received, so multi-byte fields in packets are not 81 * written in host byte order, they're written in whatever order the 82 * sending machine put them in. 83 * 84 * ntoh[ls] aren't sufficient because we might need to swap on a big-endian 85 * machine (if the file was written in little-end order). 86 */ 87#define SWAPLONG(y) \ 88((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff)) 89#define SWAPSHORT(y) \ 90 ( (((y)&0xff)<<8) | ((u_short)((y)&0xff00)>>8) ) 91 92#define SFERR_TRUNC 1 93#define SFERR_BADVERSION 2 94#define SFERR_BADF 3 95#define SFERR_EOF 4 /* not really an error, just a status */ 96 97/* 98 * Setting O_BINARY on DOS/Windows is a bit tricky 99 */ 100#if defined(WIN32) 101 #define SET_BINMODE(f) _setmode(fileno(f), O_BINARY) 102#elif defined(MSDOS) 103 #if defined(__HIGHC__) 104 #define SET_BINMODE(f) setmode(f, O_BINARY) 105 #else 106 #define SET_BINMODE(f) setmode(fileno(f), O_BINARY) 107 #endif 108#endif 109 110/* 111 * We don't write DLT_* values to the capture file header, because 112 * they're not the same on all platforms. 113 * 114 * Unfortunately, the various flavors of BSD have not always used the same 115 * numerical values for the same data types, and various patches to 116 * libpcap for non-BSD OSes have added their own DLT_* codes for link 117 * layer encapsulation types seen on those OSes, and those codes have had, 118 * in some cases, values that were also used, on other platforms, for other 119 * link layer encapsulation types. 120 * 121 * This means that capture files of a type whose numerical DLT_* code 122 * means different things on different BSDs, or with different versions 123 * of libpcap, can't always be read on systems other than those like 124 * the one running on the machine on which the capture was made. 125 * 126 * Instead, we define here a set of LINKTYPE_* codes, and map DLT_* codes 127 * to LINKTYPE_* codes when writing a savefile header, and map LINKTYPE_* 128 * codes to DLT_* codes when reading a savefile header. 129 * 130 * For those DLT_* codes that have, as far as we know, the same values on 131 * all platforms (DLT_NULL through DLT_FDDI), we define LINKTYPE_xxx as 132 * DLT_xxx; that way, captures of those types can still be read by 133 * versions of libpcap that map LINKTYPE_* values to DLT_* values, and 134 * captures of those types written by versions of libpcap that map DLT_ 135 * values to LINKTYPE_ values can still be read by older versions 136 * of libpcap. 137 * 138 * The other LINKTYPE_* codes are given values starting at 100, in the 139 * hopes that no DLT_* code will be given one of those values. 140 * 141 * In order to ensure that a given LINKTYPE_* code's value will refer to 142 * the same encapsulation type on all platforms, you should not allocate 143 * a new LINKTYPE_* value without consulting "tcpdump-workers@tcpdump.org". 144 * The tcpdump developers will allocate a value for you, and will not 145 * subsequently allocate it to anybody else; that value will be added to 146 * the "pcap.h" in the tcpdump.org CVS repository, so that a future 147 * libpcap release will include it. 148 * 149 * You should, if possible, also contribute patches to libpcap and tcpdump 150 * to handle the new encapsulation type, so that they can also be checked 151 * into the tcpdump.org CVS repository and so that they will appear in 152 * future libpcap and tcpdump releases. 153 * 154 * Do *NOT* assume that any values after the largest value in this file 155 * are available; you might not have the most up-to-date version of this 156 * file, and new values after that one might have been assigned. Also, 157 * do *NOT* use any values below 100 - those might already have been 158 * taken by one (or more!) organizations. 159 */ 160#define LINKTYPE_NULL DLT_NULL 161#define LINKTYPE_ETHERNET DLT_EN10MB /* also for 100Mb and up */ 162#define LINKTYPE_EXP_ETHERNET DLT_EN3MB /* 3Mb experimental Ethernet */ 163#define LINKTYPE_AX25 DLT_AX25 164#define LINKTYPE_PRONET DLT_PRONET 165#define LINKTYPE_CHAOS DLT_CHAOS 166#define LINKTYPE_TOKEN_RING DLT_IEEE802 /* DLT_IEEE802 is used for Token Ring */ 167#define LINKTYPE_ARCNET DLT_ARCNET /* BSD-style headers */ 168#define LINKTYPE_SLIP DLT_SLIP 169#define LINKTYPE_PPP DLT_PPP 170#define LINKTYPE_FDDI DLT_FDDI 171 172/* 173 * LINKTYPE_PPP is for use when there might, or might not, be an RFC 1662 174 * PPP in HDLC-like framing header (with 0xff 0x03 before the PPP protocol 175 * field) at the beginning of the packet. 176 * 177 * This is for use when there is always such a header; the address field 178 * might be 0xff, for regular PPP, or it might be an address field for Cisco 179 * point-to-point with HDLC framing as per section 4.3.1 of RFC 1547 ("Cisco 180 * HDLC"). This is, for example, what you get with NetBSD's DLT_PPP_SERIAL. 181 * 182 * We give it the same value as NetBSD's DLT_PPP_SERIAL, in the hopes that 183 * nobody else will choose a DLT_ value of 50, and so that DLT_PPP_SERIAL 184 * captures will be written out with a link type that NetBSD's tcpdump 185 * can read. 186 */ 187#define LINKTYPE_PPP_HDLC 50 /* PPP in HDLC-like framing */ 188 189#define LINKTYPE_PPP_ETHER 51 /* NetBSD PPP-over-Ethernet */ 190 191#define LINKTYPE_SYMANTEC_FIREWALL 99 /* Symantec Enterprise Firewall */ 192 193#define LINKTYPE_ATM_RFC1483 100 /* LLC/SNAP-encapsulated ATM */ 194#define LINKTYPE_RAW 101 /* raw IP */ 195#define LINKTYPE_SLIP_BSDOS 102 /* BSD/OS SLIP BPF header */ 196#define LINKTYPE_PPP_BSDOS 103 /* BSD/OS PPP BPF header */ 197#define LINKTYPE_C_HDLC 104 /* Cisco HDLC */ 198#define LINKTYPE_IEEE802_11 105 /* IEEE 802.11 (wireless) */ 199#define LINKTYPE_ATM_CLIP 106 /* Linux Classical IP over ATM */ 200#define LINKTYPE_FRELAY 107 /* Frame Relay */ 201#define LINKTYPE_LOOP 108 /* OpenBSD loopback */ 202#define LINKTYPE_ENC 109 /* OpenBSD IPSEC enc */ 203 204/* 205 * These three types are reserved for future use. 206 */ 207#define LINKTYPE_LANE8023 110 /* ATM LANE + 802.3 */ 208#define LINKTYPE_HIPPI 111 /* NetBSD HIPPI */ 209#define LINKTYPE_HDLC 112 /* NetBSD HDLC framing */ 210 211#define LINKTYPE_LINUX_SLL 113 /* Linux cooked socket capture */ 212#define LINKTYPE_LTALK 114 /* Apple LocalTalk hardware */ 213#define LINKTYPE_ECONET 115 /* Acorn Econet */ 214 215/* 216 * Reserved for use with OpenBSD ipfilter. 217 */ 218#define LINKTYPE_IPFILTER 116 219 220#define LINKTYPE_PFLOG 117 /* OpenBSD DLT_PFLOG */ 221#define LINKTYPE_CISCO_IOS 118 /* For Cisco-internal use */ 222#define LINKTYPE_PRISM_HEADER 119 /* 802.11+Prism II monitor mode */ 223#define LINKTYPE_AIRONET_HEADER 120 /* FreeBSD Aironet driver stuff */ 224 225/* 226 * Reserved for Siemens HiPath HDLC. 227 */ 228#define LINKTYPE_HHDLC 121 229 230#define LINKTYPE_IP_OVER_FC 122 /* RFC 2625 IP-over-Fibre Channel */ 231#define LINKTYPE_SUNATM 123 /* Solaris+SunATM */ 232 233/* 234 * Reserved as per request from Kent Dahlgren <kent@praesum.com> 235 * for private use. 236 */ 237#define LINKTYPE_RIO 124 /* RapidIO */ 238#define LINKTYPE_PCI_EXP 125 /* PCI Express */ 239#define LINKTYPE_AURORA 126 /* Xilinx Aurora link layer */ 240 241#define LINKTYPE_IEEE802_11_RADIO 127 /* 802.11 plus BSD radio header */ 242 243/* 244 * Reserved for the TZSP encapsulation, as per request from 245 * Chris Waters <chris.waters@networkchemistry.com> 246 * TZSP is a generic encapsulation for any other link type, 247 * which includes a means to include meta-information 248 * with the packet, e.g. signal strength and channel 249 * for 802.11 packets. 250 */ 251#define LINKTYPE_TZSP 128 /* Tazmen Sniffer Protocol */ 252 253#define LINKTYPE_ARCNET_LINUX 129 /* Linux-style headers */ 254 255/* 256 * Juniper-private data link types, as per request from 257 * Hannes Gredler <hannes@juniper.net>. The corresponding 258 * DLT_s are used for passing on chassis-internal 259 * metainformation such as QOS profiles, etc.. 260 */ 261#define LINKTYPE_JUNIPER_MLPPP 130 262#define LINKTYPE_JUNIPER_MLFR 131 263#define LINKTYPE_JUNIPER_ES 132 264#define LINKTYPE_JUNIPER_GGSN 133 265#define LINKTYPE_JUNIPER_MFR 134 266#define LINKTYPE_JUNIPER_ATM2 135 267#define LINKTYPE_JUNIPER_SERVICES 136 268#define LINKTYPE_JUNIPER_ATM1 137 269 270#define LINKTYPE_APPLE_IP_OVER_IEEE1394 138 /* Apple IP-over-IEEE 1394 cooked header */ 271 272#define LINKTYPE_RAWSS7 139 /* see rawss7.h for */ 273#define LINKTYPE_RAWSS7_MTP2 140 /* information on these */ 274#define LINKTYPE_RAWSS7_MTP3 141 /* definitions */ 275#define LINKTYPE_RAWSS7_SCCP 142 276 277#define LINKTYPE_DOCSIS 143 /* DOCSIS MAC frames */ 278 279#define LINKTYPE_LINUX_IRDA 144 /* Linux-IrDA */ 280 281/* 282 * Reserved for IBM SP switch and IBM Next Federation switch. 283 */ 284#define LINKTYPE_IBM_SP 145 285#define LINKTYPE_IBM_SN 146 286 287/* 288 * Reserved for private use. If you have some link-layer header type 289 * that you want to use within your organization, with the capture files 290 * using that link-layer header type not ever be sent outside your 291 * organization, you can use these values. 292 * 293 * No libpcap release will use these for any purpose, nor will any 294 * tcpdump release use them, either. 295 * 296 * Do *NOT* use these in capture files that you expect anybody not using 297 * your private versions of capture-file-reading tools to read; in 298 * particular, do *NOT* use them in products, otherwise you may find that 299 * people won't be able to use tcpdump, or snort, or Ethereal, or... to 300 * read capture files from your firewall/intrusion detection/traffic 301 * monitoring/etc. appliance, or whatever product uses that LINKTYPE_ value, 302 * and you may also find that the developers of those applications will 303 * not accept patches to let them read those files. 304 * 305 * Also, do not use them if somebody might send you a capture using them 306 * for *their* private type and tools using them for *your* private type 307 * would have to read them. 308 * 309 * Instead, in those cases, ask "tcpdump-workers@tcpdump.org" for a new DLT_ 310 * and LINKTYPE_ value, as per the comment in pcap-bpf.h, and use the type 311 * you're given. 312 */ 313#define LINKTYPE_USER0 147 314#define LINKTYPE_USER1 148 315#define LINKTYPE_USER2 149 316#define LINKTYPE_USER3 150 317#define LINKTYPE_USER4 151 318#define LINKTYPE_USER5 152 319#define LINKTYPE_USER6 153 320#define LINKTYPE_USER7 154 321#define LINKTYPE_USER8 155 322#define LINKTYPE_USER9 156 323#define LINKTYPE_USER10 157 324#define LINKTYPE_USER11 158 325#define LINKTYPE_USER12 159 326#define LINKTYPE_USER13 160 327#define LINKTYPE_USER14 161 328#define LINKTYPE_USER15 162 329 330/* 331 * For future use with 802.11 captures - defined by AbsoluteValue 332 * Systems to store a number of bits of link-layer information 333 * including radio information: 334 * 335 * http://www.shaftnet.org/~pizza/software/capturefrm.txt 336 * 337 * but could and arguably should also be used by non-AVS Linux 338 * 802.11 drivers; that may happen in the future. 339 */ 340#define LINKTYPE_IEEE802_11_RADIO_AVS 163 /* 802.11 plus AVS radio header */ 341 342/* 343 * Juniper-private data link type, as per request from 344 * Hannes Gredler <hannes@juniper.net>. The corresponding 345 * DLT_s are used for passing on chassis-internal 346 * metainformation such as QOS profiles, etc.. 347 */ 348#define LINKTYPE_JUNIPER_MONITOR 164 349 350/* 351 * Reserved for BACnet MS/TP. 352 */ 353#define LINKTYPE_BACNET_MS_TP 165 354 355/* 356 * Another PPP variant as per request from Karsten Keil <kkeil@suse.de>. 357 * 358 * This is used in some OSes to allow a kernel socket filter to distinguish 359 * between incoming and outgoing packets, on a socket intended to 360 * supply pppd with outgoing packets so it can do dial-on-demand and 361 * hangup-on-lack-of-demand; incoming packets are filtered out so they 362 * don't cause pppd to hold the connection up (you don't want random 363 * input packets such as port scans, packets from old lost connections, 364 * etc. to force the connection to stay up). 365 * 366 * The first byte of the PPP header (0xff03) is modified to accomodate 367 * the direction - 0x00 = IN, 0x01 = OUT. 368 */ 369#define LINKTYPE_PPP_PPPD 166 370 371/* 372 * Juniper-private data link type, as per request from 373 * Hannes Gredler <hannes@juniper.net>. The DLT_s are used 374 * for passing on chassis-internal metainformation such as 375 * QOS profiles, cookies, etc.. 376 */ 377#define LINKTYPE_JUNIPER_PPPOE 167 378#define LINKTYPE_JUNIPER_PPPOE_ATM 168 379 380#define LINKTYPE_GPRS_LLC 169 /* GPRS LLC */ 381#define LINKTYPE_GPF_T 170 /* GPF-T (ITU-T G.7041/Y.1303) */ 382#define LINKTYPE_GPF_F 171 /* GPF-T (ITU-T G.7041/Y.1303) */ 383 384/* 385 * Requested by Oolan Zimmer <oz@gcom.com> for use in Gcom's T1/E1 line 386 * monitoring equipment. 387 */ 388#define LINKTYPE_GCOM_T1E1 172 389#define LINKTYPE_GCOM_SERIAL 173 390 391/* 392 * Juniper-private data link type, as per request from 393 * Hannes Gredler <hannes@juniper.net>. The DLT_ is used 394 * for internal communication to Physical Interface Cards (PIC) 395 */ 396#define LINKTYPE_JUNIPER_PIC_PEER 174 397 398/* 399 * Link types requested by Gregor Maier <gregor@endace.com> of Endace 400 * Measurement Systems. They add an ERF header (see 401 * http://www.endace.com/support/EndaceRecordFormat.pdf) in front of 402 * the link-layer header. 403 */ 404#define LINKTYPE_ERF_ETH 175 /* Ethernet */ 405#define LINKTYPE_ERF_POS 176 /* Packet-over-SONET */ 406 407static struct linktype_map { 408 int dlt; 409 int linktype; 410} map[] = { 411 /* 412 * These DLT_* codes have LINKTYPE_* codes with values identical 413 * to the values of the corresponding DLT_* code. 414 */ 415 { DLT_NULL, LINKTYPE_NULL }, 416 { DLT_EN10MB, LINKTYPE_ETHERNET }, 417 { DLT_EN3MB, LINKTYPE_EXP_ETHERNET }, 418 { DLT_AX25, LINKTYPE_AX25 }, 419 { DLT_PRONET, LINKTYPE_PRONET }, 420 { DLT_CHAOS, LINKTYPE_CHAOS }, 421 { DLT_IEEE802, LINKTYPE_TOKEN_RING }, 422 { DLT_ARCNET, LINKTYPE_ARCNET }, 423 { DLT_SLIP, LINKTYPE_SLIP }, 424 { DLT_PPP, LINKTYPE_PPP }, 425 { DLT_FDDI, LINKTYPE_FDDI }, 426 427 /* 428 * These DLT_* codes have different values on different 429 * platforms; we map them to LINKTYPE_* codes that 430 * have values that should never be equal to any DLT_* 431 * code. 432 */ 433#ifdef DLT_FR 434 /* BSD/OS Frame Relay */ 435 { DLT_FR, LINKTYPE_FRELAY }, 436#endif 437 438 { DLT_SYMANTEC_FIREWALL, LINKTYPE_SYMANTEC_FIREWALL }, 439 { DLT_ATM_RFC1483, LINKTYPE_ATM_RFC1483 }, 440 { DLT_RAW, LINKTYPE_RAW }, 441 { DLT_SLIP_BSDOS, LINKTYPE_SLIP_BSDOS }, 442 { DLT_PPP_BSDOS, LINKTYPE_PPP_BSDOS }, 443 444 /* BSD/OS Cisco HDLC */ 445 { DLT_C_HDLC, LINKTYPE_C_HDLC }, 446 447 /* 448 * These DLT_* codes are not on all platforms, but, so far, 449 * there don't appear to be any platforms that define 450 * other codes with those values; we map them to 451 * different LINKTYPE_* values anyway, just in case. 452 */ 453 454 /* Linux ATM Classical IP */ 455 { DLT_ATM_CLIP, LINKTYPE_ATM_CLIP }, 456 457 /* NetBSD sync/async serial PPP (or Cisco HDLC) */ 458 { DLT_PPP_SERIAL, LINKTYPE_PPP_HDLC }, 459 460 /* NetBSD PPP over Ethernet */ 461 { DLT_PPP_ETHER, LINKTYPE_PPP_ETHER }, 462 463 /* IEEE 802.11 wireless */ 464 { DLT_IEEE802_11, LINKTYPE_IEEE802_11 }, 465 466 /* Frame Relay */ 467 { DLT_FRELAY, LINKTYPE_FRELAY }, 468 469 /* OpenBSD loopback */ 470 { DLT_LOOP, LINKTYPE_LOOP }, 471 472 /* Linux cooked socket capture */ 473 { DLT_LINUX_SLL, LINKTYPE_LINUX_SLL }, 474 475 /* Apple LocalTalk hardware */ 476 { DLT_LTALK, LINKTYPE_LTALK }, 477 478 /* Acorn Econet */ 479 { DLT_ECONET, LINKTYPE_ECONET }, 480 481 /* OpenBSD DLT_PFLOG */ 482 { DLT_PFLOG, LINKTYPE_PFLOG }, 483 484 /* For Cisco-internal use */ 485 { DLT_CISCO_IOS, LINKTYPE_CISCO_IOS }, 486 487 /* Prism II monitor-mode header plus 802.11 header */ 488 { DLT_PRISM_HEADER, LINKTYPE_PRISM_HEADER }, 489 490 /* FreeBSD Aironet driver stuff */ 491 { DLT_AIRONET_HEADER, LINKTYPE_AIRONET_HEADER }, 492 493 /* Siemens HiPath HDLC */ 494 { DLT_HHDLC, LINKTYPE_HHDLC }, 495 496 /* RFC 2625 IP-over-Fibre Channel */ 497 { DLT_IP_OVER_FC, LINKTYPE_IP_OVER_FC }, 498 499 /* Solaris+SunATM */ 500 { DLT_SUNATM, LINKTYPE_SUNATM }, 501 502 /* RapidIO */ 503 { DLT_RIO, LINKTYPE_RIO }, 504 505 /* PCI Express */ 506 { DLT_PCI_EXP, LINKTYPE_PCI_EXP }, 507 508 /* Xilinx Aurora link layer */ 509 { DLT_AURORA, LINKTYPE_AURORA }, 510 511 /* 802.11 plus BSD radio header */ 512 { DLT_IEEE802_11_RADIO, LINKTYPE_IEEE802_11_RADIO }, 513 514 /* Tazmen Sniffer Protocol */ 515 { DLT_TZSP, LINKTYPE_TZSP }, 516 517 /* Arcnet with Linux-style link-layer headers */ 518 { DLT_ARCNET_LINUX, LINKTYPE_ARCNET_LINUX }, 519 520 /* Juniper-internal chassis encapsulation */ 521 { DLT_JUNIPER_MLPPP, LINKTYPE_JUNIPER_MLPPP }, 522 { DLT_JUNIPER_MLFR, LINKTYPE_JUNIPER_MLFR }, 523 { DLT_JUNIPER_ES, LINKTYPE_JUNIPER_ES }, 524 { DLT_JUNIPER_GGSN, LINKTYPE_JUNIPER_GGSN }, 525 { DLT_JUNIPER_MFR, LINKTYPE_JUNIPER_MFR }, 526 { DLT_JUNIPER_ATM2, LINKTYPE_JUNIPER_ATM2 }, 527 { DLT_JUNIPER_SERVICES, LINKTYPE_JUNIPER_SERVICES }, 528 { DLT_JUNIPER_ATM1, LINKTYPE_JUNIPER_ATM1 }, 529 530 /* Apple IP-over-IEEE 1394 cooked header */ 531 { DLT_APPLE_IP_OVER_IEEE1394, LINKTYPE_APPLE_IP_OVER_IEEE1394 }, 532 533 /* DOCSIS MAC frames */ 534 { DLT_DOCSIS, LINKTYPE_DOCSIS }, 535 536 /* IrDA IrLAP packets + Linux-cooked header */ 537 { DLT_LINUX_IRDA, LINKTYPE_LINUX_IRDA }, 538 539 /* IBM SP and Next Federation switches */ 540 { DLT_IBM_SP, LINKTYPE_IBM_SP }, 541 { DLT_IBM_SN, LINKTYPE_IBM_SN }, 542 543 /* 802.11 plus AVS radio header */ 544 { DLT_IEEE802_11_RADIO_AVS, LINKTYPE_IEEE802_11_RADIO_AVS }, 545 546 /* 547 * Any platform that defines additional DLT_* codes should: 548 * 549 * request a LINKTYPE_* code and value from tcpdump.org, 550 * as per the above; 551 * 552 * add, in their version of libpcap, an entry to map 553 * those DLT_* codes to the corresponding LINKTYPE_* 554 * code; 555 * 556 * redefine, in their "net/bpf.h", any DLT_* values 557 * that collide with the values used by their additional 558 * DLT_* codes, to remove those collisions (but without 559 * making them collide with any of the LINKTYPE_* 560 * values equal to 50 or above; they should also avoid 561 * defining DLT_* values that collide with those 562 * LINKTYPE_* values, either). 563 */ 564 565 /* Juniper-internal chassis encapsulation */ 566 { DLT_JUNIPER_MONITOR, LINKTYPE_JUNIPER_MONITOR }, 567 568 /* BACnet MS/TP */ 569 { DLT_BACNET_MS_TP, LINKTYPE_BACNET_MS_TP }, 570 571 /* PPP for pppd, with direction flag in the PPP header */ 572 { DLT_PPP_PPPD, LINKTYPE_PPP_PPPD}, 573 574 /* Juniper-internal chassis encapsulation */ 575 { DLT_JUNIPER_PPPOE, LINKTYPE_JUNIPER_PPPOE }, 576 { DLT_JUNIPER_PPPOE_ATM,LINKTYPE_JUNIPER_PPPOE_ATM }, 577 578 /* GPRS LLC */ 579 { DLT_GPRS_LLC, LINKTYPE_GPRS_LLC }, 580 581 /* Transparent Generic Framing Procedure (ITU-T G.7041/Y.1303) */ 582 { DLT_GPF_T, LINKTYPE_GPF_T }, 583 584 /* Framed Generic Framing Procedure (ITU-T G.7041/Y.1303) */ 585 { DLT_GPF_F, LINKTYPE_GPF_F }, 586 587 { DLT_GCOM_T1E1, LINKTYPE_GCOM_T1E1 }, 588 { DLT_GCOM_SERIAL, LINKTYPE_GCOM_SERIAL }, 589 590 /* Juniper-internal chassis encapsulation */ 591 { DLT_JUNIPER_PIC_PEER, LINKTYPE_JUNIPER_PIC_PEER }, 592 593 /* Endace types */ 594 { DLT_ERF_ETH, LINKTYPE_ERF_ETH }, 595 { DLT_ERF_POS, LINKTYPE_ERF_POS }, 596 597 { -1, -1 } 598}; 599 600static int 601dlt_to_linktype(int dlt) 602{ 603 int i; 604 605 for (i = 0; map[i].dlt != -1; i++) { 606 if (map[i].dlt == dlt) 607 return (map[i].linktype); 608 } 609 610 /* 611 * If we don't have a mapping for this DLT_ code, return an 612 * error; that means that the table above needs to have an 613 * entry added. 614 */ 615 return (-1); 616} 617 618static int 619linktype_to_dlt(int linktype) 620{ 621 int i; 622 623 for (i = 0; map[i].linktype != -1; i++) { 624 if (map[i].linktype == linktype) 625 return (map[i].dlt); 626 } 627 628 /* 629 * If we don't have an entry for this link type, return 630 * the link type value; it may be a DLT_ value from an 631 * older version of libpcap. 632 */ 633 return linktype; 634} 635 636static int 637sf_write_header(FILE *fp, int linktype, int thiszone, int snaplen) 638{ 639 struct pcap_file_header hdr; 640 641 hdr.magic = TCPDUMP_MAGIC; 642 hdr.version_major = PCAP_VERSION_MAJOR; 643 hdr.version_minor = PCAP_VERSION_MINOR; 644 645 hdr.thiszone = thiszone; 646 hdr.snaplen = snaplen; 647 hdr.sigfigs = 0; 648 hdr.linktype = linktype; 649 650 if (fwrite((char *)&hdr, sizeof(hdr), 1, fp) != 1) 651 return (-1); 652 653 return (0); 654} 655 656static void 657swap_hdr(struct pcap_file_header *hp) 658{ 659 hp->version_major = SWAPSHORT(hp->version_major); 660 hp->version_minor = SWAPSHORT(hp->version_minor); 661 hp->thiszone = SWAPLONG(hp->thiszone); 662 hp->sigfigs = SWAPLONG(hp->sigfigs); 663 hp->snaplen = SWAPLONG(hp->snaplen); 664 hp->linktype = SWAPLONG(hp->linktype); 665} 666 667static int 668sf_getnonblock(pcap_t *p, char *errbuf) 669{ 670 /* 671 * This is a savefile, not a live capture file, so never say 672 * it's in non-blocking mode. 673 */ 674 return (0); 675} 676 677static int 678sf_setnonblock(pcap_t *p, int nonblock, char *errbuf) 679{ 680 /* 681 * This is a savefile, not a live capture file, so ignore 682 * requests to put it in non-blocking mode. 683 */ 684 return (0); 685} 686 687static int 688sf_stats(pcap_t *p, struct pcap_stat *ps) 689{ 690 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 691 "Statistics aren't available from savefiles"); 692 return (-1); 693} 694 695static int 696sf_inject(pcap_t *p, const void *buf _U_, size_t size _U_) 697{ 698 strlcpy(p->errbuf, "Sending packets isn't supported on savefiles", 699 PCAP_ERRBUF_SIZE); 700 return (-1); 701} 702 703static void 704sf_close(pcap_t *p) 705{ 706 if (p->sf.rfile != stdin) 707 (void)fclose(p->sf.rfile); 708 if (p->sf.base != NULL) 709 free(p->sf.base); 710} 711 712pcap_t * 713pcap_open_offline(const char *fname, char *errbuf) 714{ 715 FILE *fp; 716 pcap_t *p; 717 718 if (fname[0] == '-' && fname[1] == '\0') 719 fp = stdin; 720 else { 721#if !defined(WIN32) && !defined(MSDOS) 722 fp = fopen(fname, "r"); 723#else 724 fp = fopen(fname, "rb"); 725#endif 726 if (fp == NULL) { 727 snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", fname, 728 pcap_strerror(errno)); 729 return (NULL); 730 } 731 } 732 p = pcap_fopen_offline(fp, errbuf); 733 if (p == NULL) { 734 if (fp != stdin) 735 fclose(fp); 736 } 737 return (p); 738} 739 740pcap_t * 741pcap_fopen_offline(FILE *fp, char *errbuf) 742{ 743 register pcap_t *p; 744 struct pcap_file_header hdr; 745 size_t amt_read; 746 bpf_u_int32 magic; 747 int linklen; 748 749 p = (pcap_t *)malloc(sizeof(*p)); 750 if (p == NULL) { 751 strlcpy(errbuf, "out of swap", PCAP_ERRBUF_SIZE); 752 return (NULL); 753 } 754 755 memset((char *)p, 0, sizeof(*p)); 756 757 amt_read = fread((char *)&hdr, 1, sizeof(hdr), fp); 758 if (amt_read != sizeof(hdr)) { 759 if (ferror(fp)) { 760 snprintf(errbuf, PCAP_ERRBUF_SIZE, 761 "error reading dump file: %s", 762 pcap_strerror(errno)); 763 } else { 764 snprintf(errbuf, PCAP_ERRBUF_SIZE, 765 "truncated dump file; tried to read %lu file header bytes, only got %lu", 766 (unsigned long)sizeof(hdr), 767 (unsigned long)amt_read); 768 } 769 goto bad; 770 } 771 magic = hdr.magic; 772 if (magic != TCPDUMP_MAGIC && magic != KUZNETZOV_TCPDUMP_MAGIC) { 773 magic = SWAPLONG(magic); 774 if (magic != TCPDUMP_MAGIC && magic != KUZNETZOV_TCPDUMP_MAGIC) { 775 snprintf(errbuf, PCAP_ERRBUF_SIZE, 776 "bad dump file format"); 777 goto bad; 778 } 779 p->sf.swapped = 1; 780 swap_hdr(&hdr); 781 } 782 if (magic == KUZNETZOV_TCPDUMP_MAGIC) { 783 /* 784 * XXX - the patch that's in some versions of libpcap 785 * changes the packet header but not the magic number, 786 * and some other versions with this magic number have 787 * some extra debugging information in the packet header; 788 * we'd have to use some hacks^H^H^H^H^Hheuristics to 789 * detect those variants. 790 * 791 * Ethereal does that, but it does so by trying to read 792 * the first two packets of the file with each of the 793 * record header formats. That currently means it seeks 794 * backwards and retries the reads, which doesn't work 795 * on pipes. We want to be able to read from a pipe, so 796 * that strategy won't work; we'd have to buffer some 797 * data ourselves and read from that buffer in order to 798 * make that work. 799 */ 800 p->sf.hdrsize = sizeof(struct pcap_sf_patched_pkthdr); 801 } else 802 p->sf.hdrsize = sizeof(struct pcap_sf_pkthdr); 803 if (hdr.version_major < PCAP_VERSION_MAJOR) { 804 snprintf(errbuf, PCAP_ERRBUF_SIZE, "archaic file format"); 805 goto bad; 806 } 807 p->tzoff = hdr.thiszone; 808 p->snapshot = hdr.snaplen; 809 p->linktype = linktype_to_dlt(hdr.linktype); 810 p->sf.rfile = fp; 811#ifndef WIN32 812 p->bufsize = hdr.snaplen; 813#else 814 /* Allocate the space for pcap_pkthdr as well. It will be used by pcap_read_ex */ 815 p->bufsize = hdr.snaplen+sizeof(struct pcap_pkthdr); 816#endif 817 818 /* Align link header as required for proper data alignment */ 819 /* XXX should handle all types */ 820 switch (p->linktype) { 821 822 case DLT_EN10MB: 823 linklen = 14; 824 break; 825 826 case DLT_FDDI: 827 linklen = 13 + 8; /* fddi_header + llc */ 828 break; 829 830 case DLT_NULL: 831 default: 832 linklen = 0; 833 break; 834 } 835 836 if (p->bufsize < 0) 837 p->bufsize = BPF_MAXBUFSIZE; 838 p->sf.base = (u_char *)malloc(p->bufsize + BPF_ALIGNMENT); 839 if (p->sf.base == NULL) { 840 strlcpy(errbuf, "out of swap", PCAP_ERRBUF_SIZE); 841 goto bad; 842 } 843 p->buffer = p->sf.base + BPF_ALIGNMENT - (linklen % BPF_ALIGNMENT); 844 p->sf.version_major = hdr.version_major; 845 p->sf.version_minor = hdr.version_minor; 846#ifdef PCAP_FDDIPAD 847 /* Padding only needed for live capture fcode */ 848 p->fddipad = 0; 849#endif 850 851 /* 852 * We interchanged the caplen and len fields at version 2.3, 853 * in order to match the bpf header layout. But unfortunately 854 * some files were written with version 2.3 in their headers 855 * but without the interchanged fields. 856 * 857 * In addition, DG/UX tcpdump writes out files with a version 858 * number of 543.0, and with the caplen and len fields in the 859 * pre-2.3 order. 860 */ 861 switch (hdr.version_major) { 862 863 case 2: 864 if (hdr.version_minor < 3) 865 p->sf.lengths_swapped = SWAPPED; 866 else if (hdr.version_minor == 3) 867 p->sf.lengths_swapped = MAYBE_SWAPPED; 868 else 869 p->sf.lengths_swapped = NOT_SWAPPED; 870 break; 871 872 case 543: 873 p->sf.lengths_swapped = SWAPPED; 874 break; 875 876 default: 877 p->sf.lengths_swapped = NOT_SWAPPED; 878 break; 879 } 880 881#if !defined(WIN32) && !defined(MSDOS) 882 /* 883 * You can do "select()" and "poll()" on plain files on most 884 * platforms, and should be able to do so on pipes. 885 * 886 * You can't do "select()" on anything other than sockets in 887 * Windows, so, on Win32 systems, we don't have "selectable_fd". 888 */ 889 p->selectable_fd = fileno(fp); 890#endif 891 892 p->read_op = pcap_offline_read; 893 p->inject_op = sf_inject; 894 p->setfilter_op = install_bpf_program; 895 p->set_datalink_op = NULL; /* we don't support munging link-layer headers */ 896 p->getnonblock_op = sf_getnonblock; 897 p->setnonblock_op = sf_setnonblock; 898 p->stats_op = sf_stats; 899 p->close_op = sf_close; 900 901#if defined(WIN32) || defined(MSDOS) 902 /* 903 * If we're reading from the standard input, put it in binary 904 * mode, as savefiles are binary files. 905 */ 906 if (fp == stdin) 907 SET_BINMODE(fp); 908#endif 909 910 return (p); 911 bad: 912 free(p); 913 return (NULL); 914} 915 916/* 917 * Read sf_readfile and return the next packet. Return the header in hdr 918 * and the contents in buf. Return 0 on success, SFERR_EOF if there were 919 * no more packets, and SFERR_TRUNC if a partial packet was encountered. 920 */ 921static int 922sf_next_packet(pcap_t *p, struct pcap_pkthdr *hdr, u_char *buf, u_int buflen) 923{ 924 struct pcap_sf_patched_pkthdr sf_hdr; 925 FILE *fp = p->sf.rfile; 926 size_t amt_read; 927 bpf_u_int32 t; 928 929 /* 930 * Read the packet header; the structure we use as a buffer 931 * is the longer structure for files generated by the patched 932 * libpcap, but if the file has the magic number for an 933 * unpatched libpcap we only read as many bytes as the regular 934 * header has. 935 */ 936 amt_read = fread(&sf_hdr, 1, p->sf.hdrsize, fp); 937 if (amt_read != p->sf.hdrsize) { 938 if (ferror(fp)) { 939 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 940 "error reading dump file: %s", 941 pcap_strerror(errno)); 942 return (-1); 943 } else { 944 if (amt_read != 0) { 945 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 946 "truncated dump file; tried to read %d header bytes, only got %lu", 947 p->sf.hdrsize, (unsigned long)amt_read); 948 return (-1); 949 } 950 /* EOF */ 951 return (1); 952 } 953 } 954 955 if (p->sf.swapped) { 956 /* these were written in opposite byte order */ 957 hdr->caplen = SWAPLONG(sf_hdr.caplen); 958 hdr->len = SWAPLONG(sf_hdr.len); 959 hdr->ts.tv_sec = SWAPLONG(sf_hdr.ts.tv_sec); 960 hdr->ts.tv_usec = SWAPLONG(sf_hdr.ts.tv_usec); 961 } else { 962 hdr->caplen = sf_hdr.caplen; 963 hdr->len = sf_hdr.len; 964 hdr->ts.tv_sec = sf_hdr.ts.tv_sec; 965 hdr->ts.tv_usec = sf_hdr.ts.tv_usec; 966 } 967 /* Swap the caplen and len fields, if necessary. */ 968 switch (p->sf.lengths_swapped) { 969 970 case NOT_SWAPPED: 971 break; 972 973 case MAYBE_SWAPPED: 974 if (hdr->caplen <= hdr->len) { 975 /* 976 * The captured length is <= the actual length, 977 * so presumably they weren't swapped. 978 */ 979 break; 980 } 981 /* FALLTHROUGH */ 982 983 case SWAPPED: 984 t = hdr->caplen; 985 hdr->caplen = hdr->len; 986 hdr->len = t; 987 break; 988 } 989 990 if (hdr->caplen > buflen) { 991 /* 992 * This can happen due to Solaris 2.3 systems tripping 993 * over the BUFMOD problem and not setting the snapshot 994 * correctly in the savefile header. If the caplen isn't 995 * grossly wrong, try to salvage. 996 */ 997 static u_char *tp = NULL; 998 static size_t tsize = 0; 999 1000 if (hdr->caplen > 65535) { 1001 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 1002 "bogus savefile header"); 1003 return (-1); 1004 } 1005 1006 if (tsize < hdr->caplen) { 1007 tsize = ((hdr->caplen + 1023) / 1024) * 1024; 1008 if (tp != NULL) 1009 free((u_char *)tp); 1010 tp = (u_char *)malloc(tsize); 1011 if (tp == NULL) { 1012 tsize = 0; 1013 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 1014 "BUFMOD hack malloc"); 1015 return (-1); 1016 } 1017 } 1018 amt_read = fread((char *)tp, 1, hdr->caplen, fp); 1019 if (amt_read != hdr->caplen) { 1020 if (ferror(fp)) { 1021 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 1022 "error reading dump file: %s", 1023 pcap_strerror(errno)); 1024 } else { 1025 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 1026 "truncated dump file; tried to read %u captured bytes, only got %lu", 1027 hdr->caplen, (unsigned long)amt_read); 1028 } 1029 return (-1); 1030 } 1031 /* 1032 * We can only keep up to buflen bytes. Since caplen > buflen 1033 * is exactly how we got here, we know we can only keep the 1034 * first buflen bytes and must drop the remainder. Adjust 1035 * caplen accordingly, so we don't get confused later as 1036 * to how many bytes we have to play with. 1037 */ 1038 hdr->caplen = buflen; 1039 memcpy((char *)buf, (char *)tp, buflen); 1040 1041 } else { 1042 /* read the packet itself */ 1043 amt_read = fread((char *)buf, 1, hdr->caplen, fp); 1044 if (amt_read != hdr->caplen) { 1045 if (ferror(fp)) { 1046 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 1047 "error reading dump file: %s", 1048 pcap_strerror(errno)); 1049 } else { 1050 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 1051 "truncated dump file; tried to read %u captured bytes, only got %lu", 1052 hdr->caplen, (unsigned long)amt_read); 1053 } 1054 return (-1); 1055 } 1056 } 1057 return (0); 1058} 1059 1060/* 1061 * Print out packets stored in the file initialized by sf_read_init(). 1062 * If cnt > 0, return after 'cnt' packets, otherwise continue until eof. 1063 */ 1064int 1065pcap_offline_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user) 1066{ 1067 struct bpf_insn *fcode; 1068 int status = 0; 1069 int n = 0; 1070 1071 while (status == 0) { 1072 struct pcap_pkthdr h; 1073 1074 /* 1075 * Has "pcap_breakloop()" been called? 1076 * If so, return immediately - if we haven't read any 1077 * packets, clear the flag and return -2 to indicate 1078 * that we were told to break out of the loop, otherwise 1079 * leave the flag set, so that the *next* call will break 1080 * out of the loop without having read any packets, and 1081 * return the number of packets we've processed so far. 1082 */ 1083 if (p->break_loop) { 1084 if (n == 0) { 1085 p->break_loop = 0; 1086 return (-2); 1087 } else 1088 return (n); 1089 } 1090 1091 status = sf_next_packet(p, &h, p->buffer, p->bufsize); 1092 if (status) { 1093 if (status == 1) 1094 return (0); 1095 return (status); 1096 } 1097 1098 if ((fcode = p->fcode.bf_insns) == NULL || 1099 bpf_filter(fcode, p->buffer, h.len, h.caplen)) { 1100 (*callback)(user, &h, p->buffer); 1101 if (++n >= cnt && cnt > 0) 1102 break; 1103 } 1104 } 1105 /*XXX this breaks semantics tcpslice expects */ 1106 return (n); 1107} 1108 1109/* 1110 * Output a packet to the initialized dump file. 1111 */ 1112void 1113pcap_dump(u_char *user, const struct pcap_pkthdr *h, const u_char *sp) 1114{ 1115 register FILE *f; 1116 struct pcap_sf_pkthdr sf_hdr; 1117 1118 f = (FILE *)user; 1119 sf_hdr.ts.tv_sec = h->ts.tv_sec; 1120 sf_hdr.ts.tv_usec = h->ts.tv_usec; 1121 sf_hdr.caplen = h->caplen; 1122 sf_hdr.len = h->len; 1123 /* XXX we should check the return status */ 1124 (void)fwrite(&sf_hdr, sizeof(sf_hdr), 1, f); 1125 (void)fwrite((char *)sp, h->caplen, 1, f); 1126} 1127 1128static pcap_dumper_t * 1129pcap_setup_dump(pcap_t *p, int linktype, FILE *f, const char *fname) 1130{ 1131 1132#if defined(WIN32) || defined(MSDOS) 1133 /* 1134 * If we're writing to the standard output, put it in binary 1135 * mode, as savefiles are binary files. 1136 * 1137 * Otherwise, we turn off buffering. 1138 * XXX - why? And why not on the standard output? 1139 */ 1140 if (f == stdout) 1141 SET_BINMODE(f); 1142 else 1143 setbuf(f, NULL); 1144#endif 1145 if (sf_write_header(f, linktype, p->tzoff, p->snapshot) == -1) { 1146 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "Can't write to %s: %s", 1147 fname, pcap_strerror(errno)); 1148 if (f != stdout) 1149 (void)fclose(f); 1150 return (NULL); 1151 } 1152 return ((pcap_dumper_t *)f); 1153} 1154 1155/* 1156 * Initialize so that sf_write() will output to the file named 'fname'. 1157 */ 1158pcap_dumper_t * 1159pcap_dump_open(pcap_t *p, const char *fname) 1160{ 1161 FILE *f; 1162 int linktype; 1163 1164 linktype = dlt_to_linktype(p->linktype); 1165 if (linktype == -1) { 1166 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 1167 "%s: link-layer type %d isn't supported in savefiles", 1168 fname, linktype); 1169 return (NULL); 1170 } 1171 1172 if (fname[0] == '-' && fname[1] == '\0') { 1173 f = stdout; 1174 fname = "standard output"; 1175 } else { 1176#if !defined(WIN32) && !defined(MSDOS) 1177 f = fopen(fname, "w"); 1178#else 1179 f = fopen(fname, "wb"); 1180#endif 1181 if (f == NULL) { 1182 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "%s: %s", 1183 fname, pcap_strerror(errno)); 1184 return (NULL); 1185 } 1186 } 1187 return (pcap_setup_dump(p, linktype, f, fname)); 1188} 1189 1190/* 1191 * Initialize so that sf_write() will output to the given stream. 1192 */ 1193pcap_dumper_t * 1194pcap_dump_fopen(pcap_t *p, FILE *f) 1195{ 1196 int linktype; 1197 1198 linktype = dlt_to_linktype(p->linktype); 1199 if (linktype == -1) { 1200 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, 1201 "stream: link-layer type %d isn't supported in savefiles", 1202 linktype); 1203 return (NULL); 1204 } 1205 1206 return (pcap_setup_dump(p, linktype, f, "stream")); 1207} 1208 1209FILE * 1210pcap_dump_file(pcap_dumper_t *p) 1211{ 1212 return ((FILE *)p); 1213} 1214 1215int 1216pcap_dump_flush(pcap_dumper_t *p) 1217{ 1218 1219 if (fflush((FILE *)p) == EOF) 1220 return (-1); 1221 else 1222 return (0); 1223} 1224 1225void 1226pcap_dump_close(pcap_dumper_t *p) 1227{ 1228 1229#ifdef notyet 1230 if (ferror((FILE *)p)) 1231 return-an-error; 1232 /* XXX should check return from fclose() too */ 1233#endif 1234 (void)fclose((FILE *)p); 1235} 1236