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
32 static const char rcsid[] _U_ =
33 "@(#) $Header: /tcpdump/master/libpcap/savefile.c,v 1.126.2.30 2007/08/14 20:57:49 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 * Normal libpcap format, except for seconds/nanoseconds timestamps,
76 * as per a request by Ulf Lamping <ulf.lamping@web.de>
77 */
78 #define NSEC_TCPDUMP_MAGIC 0xa1b23c4d
79
80 /*
81 * We use the "receiver-makes-right" approach to byte order,
82 * because time is at a premium when we are writing the file.
83 * In other words, the pcap_file_header and pcap_pkthdr,
84 * records are written in host byte order.
85 * Note that the bytes of packet data are written out in the order in
86 * which they were received, so multi-byte fields in packets are not
87 * written in host byte order, they're written in whatever order the
88 * sending machine put them in.
89 *
90 * ntoh[ls] aren't sufficient because we might need to swap on a big-endian
91 * machine (if the file was written in little-end order).
92 */
93 #define SWAPLONG(y) \
94 ((((y)&0xff)<<24) | (((y)&0xff00)<<8) | (((y)&0xff0000)>>8) | (((y)>>24)&0xff))
95 #define SWAPSHORT(y) \
96 ( (((y)&0xff)<<8) | ((u_short)((y)&0xff00)>>8) )
97
98 #define SFERR_TRUNC 1
99 #define SFERR_BADVERSION 2
100 #define SFERR_BADF 3
101 #define SFERR_EOF 4 /* not really an error, just a status */
102
103 /*
104 * Setting O_BINARY on DOS/Windows is a bit tricky
105 */
106 #if defined(WIN32)
107 #define SET_BINMODE(f) _setmode(_fileno(f), _O_BINARY)
108 #elif defined(MSDOS)
109 #if defined(__HIGHC__)
110 #define SET_BINMODE(f) setmode(f, O_BINARY)
111 #else
112 #define SET_BINMODE(f) setmode(fileno(f), O_BINARY)
113 #endif
114 #endif
115
116 /*
117 * We don't write DLT_* values to the capture file header, because
118 * they're not the same on all platforms.
119 *
120 * Unfortunately, the various flavors of BSD have not always used the same
121 * numerical values for the same data types, and various patches to
122 * libpcap for non-BSD OSes have added their own DLT_* codes for link
123 * layer encapsulation types seen on those OSes, and those codes have had,
124 * in some cases, values that were also used, on other platforms, for other
125 * link layer encapsulation types.
126 *
127 * This means that capture files of a type whose numerical DLT_* code
128 * means different things on different BSDs, or with different versions
129 * of libpcap, can't always be read on systems other than those like
130 * the one running on the machine on which the capture was made.
131 *
132 * Instead, we define here a set of LINKTYPE_* codes, and map DLT_* codes
133 * to LINKTYPE_* codes when writing a savefile header, and map LINKTYPE_*
134 * codes to DLT_* codes when reading a savefile header.
135 *
136 * For those DLT_* codes that have, as far as we know, the same values on
137 * all platforms (DLT_NULL through DLT_FDDI), we define LINKTYPE_xxx as
138 * DLT_xxx; that way, captures of those types can still be read by
139 * versions of libpcap that map LINKTYPE_* values to DLT_* values, and
140 * captures of those types written by versions of libpcap that map DLT_
141 * values to LINKTYPE_ values can still be read by older versions
142 * of libpcap.
143 *
144 * The other LINKTYPE_* codes are given values starting at 100, in the
145 * hopes that no DLT_* code will be given one of those values.
146 *
147 * In order to ensure that a given LINKTYPE_* code's value will refer to
148 * the same encapsulation type on all platforms, you should not allocate
149 * a new LINKTYPE_* value without consulting "tcpdump-workers@tcpdump.org".
150 * The tcpdump developers will allocate a value for you, and will not
151 * subsequently allocate it to anybody else; that value will be added to
152 * the "pcap.h" in the tcpdump.org CVS repository, so that a future
153 * libpcap release will include it.
154 *
155 * You should, if possible, also contribute patches to libpcap and tcpdump
156 * to handle the new encapsulation type, so that they can also be checked
157 * into the tcpdump.org CVS repository and so that they will appear in
158 * future libpcap and tcpdump releases.
159 *
160 * Do *NOT* assume that any values after the largest value in this file
161 * are available; you might not have the most up-to-date version of this
162 * file, and new values after that one might have been assigned. Also,
163 * do *NOT* use any values below 100 - those might already have been
164 * taken by one (or more!) organizations.
165 */
166 #define LINKTYPE_NULL DLT_NULL
167 #define LINKTYPE_ETHERNET DLT_EN10MB /* also for 100Mb and up */
168 #define LINKTYPE_EXP_ETHERNET DLT_EN3MB /* 3Mb experimental Ethernet */
169 #define LINKTYPE_AX25 DLT_AX25
170 #define LINKTYPE_PRONET DLT_PRONET
171 #define LINKTYPE_CHAOS DLT_CHAOS
172 #define LINKTYPE_TOKEN_RING DLT_IEEE802 /* DLT_IEEE802 is used for Token Ring */
173 #define LINKTYPE_ARCNET DLT_ARCNET /* BSD-style headers */
174 #define LINKTYPE_SLIP DLT_SLIP
175 #define LINKTYPE_PPP DLT_PPP
176 #define LINKTYPE_FDDI DLT_FDDI
177
178 /*
179 * LINKTYPE_PPP is for use when there might, or might not, be an RFC 1662
180 * PPP in HDLC-like framing header (with 0xff 0x03 before the PPP protocol
181 * field) at the beginning of the packet.
182 *
183 * This is for use when there is always such a header; the address field
184 * might be 0xff, for regular PPP, or it might be an address field for Cisco
185 * point-to-point with HDLC framing as per section 4.3.1 of RFC 1547 ("Cisco
186 * HDLC"). This is, for example, what you get with NetBSD's DLT_PPP_SERIAL.
187 *
188 * We give it the same value as NetBSD's DLT_PPP_SERIAL, in the hopes that
189 * nobody else will choose a DLT_ value of 50, and so that DLT_PPP_SERIAL
190 * captures will be written out with a link type that NetBSD's tcpdump
191 * can read.
192 */
193 #define LINKTYPE_PPP_HDLC 50 /* PPP in HDLC-like framing */
194
195 #define LINKTYPE_PPP_ETHER 51 /* NetBSD PPP-over-Ethernet */
196
197 #define LINKTYPE_SYMANTEC_FIREWALL 99 /* Symantec Enterprise Firewall */
198
199 #define LINKTYPE_ATM_RFC1483 100 /* LLC/SNAP-encapsulated ATM */
200 #define LINKTYPE_RAW 101 /* raw IP */
201 #define LINKTYPE_SLIP_BSDOS 102 /* BSD/OS SLIP BPF header */
202 #define LINKTYPE_PPP_BSDOS 103 /* BSD/OS PPP BPF header */
203 #define LINKTYPE_C_HDLC 104 /* Cisco HDLC */
204 #define LINKTYPE_IEEE802_11 105 /* IEEE 802.11 (wireless) */
205 #define LINKTYPE_ATM_CLIP 106 /* Linux Classical IP over ATM */
206 #define LINKTYPE_FRELAY 107 /* Frame Relay */
207 #define LINKTYPE_LOOP 108 /* OpenBSD loopback */
208 #define LINKTYPE_ENC 109 /* OpenBSD IPSEC enc */
209
210 /*
211 * These three types are reserved for future use.
212 */
213 #define LINKTYPE_LANE8023 110 /* ATM LANE + 802.3 */
214 #define LINKTYPE_HIPPI 111 /* NetBSD HIPPI */
215 #define LINKTYPE_HDLC 112 /* NetBSD HDLC framing */
216
217 #define LINKTYPE_LINUX_SLL 113 /* Linux cooked socket capture */
218 #define LINKTYPE_LTALK 114 /* Apple LocalTalk hardware */
219 #define LINKTYPE_ECONET 115 /* Acorn Econet */
220
221 /*
222 * Reserved for use with OpenBSD ipfilter.
223 */
224 #define LINKTYPE_IPFILTER 116
225
226 #define LINKTYPE_PFLOG 117 /* OpenBSD DLT_PFLOG */
227 #define LINKTYPE_CISCO_IOS 118 /* For Cisco-internal use */
228 #define LINKTYPE_PRISM_HEADER 119 /* 802.11+Prism II monitor mode */
229 #define LINKTYPE_AIRONET_HEADER 120 /* FreeBSD Aironet driver stuff */
230
231 /*
232 * Reserved for Siemens HiPath HDLC.
233 */
234 #define LINKTYPE_HHDLC 121
235
236 #define LINKTYPE_IP_OVER_FC 122 /* RFC 2625 IP-over-Fibre Channel */
237 #define LINKTYPE_SUNATM 123 /* Solaris+SunATM */
238
239 /*
240 * Reserved as per request from Kent Dahlgren <kent@praesum.com>
241 * for private use.
242 */
243 #define LINKTYPE_RIO 124 /* RapidIO */
244 #define LINKTYPE_PCI_EXP 125 /* PCI Express */
245 #define LINKTYPE_AURORA 126 /* Xilinx Aurora link layer */
246
247 #define LINKTYPE_IEEE802_11_RADIO 127 /* 802.11 plus BSD radio header */
248
249 /*
250 * Reserved for the TZSP encapsulation, as per request from
251 * Chris Waters <chris.waters@networkchemistry.com>
252 * TZSP is a generic encapsulation for any other link type,
253 * which includes a means to include meta-information
254 * with the packet, e.g. signal strength and channel
255 * for 802.11 packets.
256 */
257 #define LINKTYPE_TZSP 128 /* Tazmen Sniffer Protocol */
258
259 #define LINKTYPE_ARCNET_LINUX 129 /* Linux-style headers */
260
261 /*
262 * Juniper-private data link types, as per request from
263 * Hannes Gredler <hannes@juniper.net>. The corresponding
264 * DLT_s are used for passing on chassis-internal
265 * metainformation such as QOS profiles, etc..
266 */
267 #define LINKTYPE_JUNIPER_MLPPP 130
268 #define LINKTYPE_JUNIPER_MLFR 131
269 #define LINKTYPE_JUNIPER_ES 132
270 #define LINKTYPE_JUNIPER_GGSN 133
271 #define LINKTYPE_JUNIPER_MFR 134
272 #define LINKTYPE_JUNIPER_ATM2 135
273 #define LINKTYPE_JUNIPER_SERVICES 136
274 #define LINKTYPE_JUNIPER_ATM1 137
275
276 #define LINKTYPE_APPLE_IP_OVER_IEEE1394 138 /* Apple IP-over-IEEE 1394 cooked header */
277
278 #define LINKTYPE_MTP2_WITH_PHDR 139
279 #define LINKTYPE_MTP2 140
280 #define LINKTYPE_MTP3 141
281 #define LINKTYPE_SCCP 142
282
283 #define LINKTYPE_DOCSIS 143 /* DOCSIS MAC frames */
284
285 #define LINKTYPE_LINUX_IRDA 144 /* Linux-IrDA */
286
287 /*
288 * Reserved for IBM SP switch and IBM Next Federation switch.
289 */
290 #define LINKTYPE_IBM_SP 145
291 #define LINKTYPE_IBM_SN 146
292
293 /*
294 * Reserved for private use. If you have some link-layer header type
295 * that you want to use within your organization, with the capture files
296 * using that link-layer header type not ever be sent outside your
297 * organization, you can use these values.
298 *
299 * No libpcap release will use these for any purpose, nor will any
300 * tcpdump release use them, either.
301 *
302 * Do *NOT* use these in capture files that you expect anybody not using
303 * your private versions of capture-file-reading tools to read; in
304 * particular, do *NOT* use them in products, otherwise you may find that
305 * people won't be able to use tcpdump, or snort, or Ethereal, or... to
306 * read capture files from your firewall/intrusion detection/traffic
307 * monitoring/etc. appliance, or whatever product uses that LINKTYPE_ value,
308 * and you may also find that the developers of those applications will
309 * not accept patches to let them read those files.
310 *
311 * Also, do not use them if somebody might send you a capture using them
312 * for *their* private type and tools using them for *your* private type
313 * would have to read them.
314 *
315 * Instead, in those cases, ask "tcpdump-workers@tcpdump.org" for a new DLT_
316 * and LINKTYPE_ value, as per the comment in pcap-bpf.h, and use the type
317 * you're given.
318 */
319 #define LINKTYPE_USER0 147
320 #define LINKTYPE_USER1 148
321 #define LINKTYPE_USER2 149
322 #define LINKTYPE_USER3 150
323 #define LINKTYPE_USER4 151
324 #define LINKTYPE_USER5 152
325 #define LINKTYPE_USER6 153
326 #define LINKTYPE_USER7 154
327 #define LINKTYPE_USER8 155
328 #define LINKTYPE_USER9 156
329 #define LINKTYPE_USER10 157
330 #define LINKTYPE_USER11 158
331 #define LINKTYPE_USER12 159
332 #define LINKTYPE_USER13 160
333 #define LINKTYPE_USER14 161
334 #define LINKTYPE_USER15 162
335
336 /*
337 * For future use with 802.11 captures - defined by AbsoluteValue
338 * Systems to store a number of bits of link-layer information
339 * including radio information:
340 *
341 * http://www.shaftnet.org/~pizza/software/capturefrm.txt
342 *
343 * but could and arguably should also be used by non-AVS Linux
344 * 802.11 drivers; that may happen in the future.
345 */
346 #define LINKTYPE_IEEE802_11_RADIO_AVS 163 /* 802.11 plus AVS radio header */
347
348 /*
349 * Juniper-private data link type, as per request from
350 * Hannes Gredler <hannes@juniper.net>. The corresponding
351 * DLT_s are used for passing on chassis-internal
352 * metainformation such as QOS profiles, etc..
353 */
354 #define LINKTYPE_JUNIPER_MONITOR 164
355
356 /*
357 * Reserved for BACnet MS/TP.
358 */
359 #define LINKTYPE_BACNET_MS_TP 165
360
361 /*
362 * Another PPP variant as per request from Karsten Keil <kkeil@suse.de>.
363 *
364 * This is used in some OSes to allow a kernel socket filter to distinguish
365 * between incoming and outgoing packets, on a socket intended to
366 * supply pppd with outgoing packets so it can do dial-on-demand and
367 * hangup-on-lack-of-demand; incoming packets are filtered out so they
368 * don't cause pppd to hold the connection up (you don't want random
369 * input packets such as port scans, packets from old lost connections,
370 * etc. to force the connection to stay up).
371 *
372 * The first byte of the PPP header (0xff03) is modified to accomodate
373 * the direction - 0x00 = IN, 0x01 = OUT.
374 */
375 #define LINKTYPE_PPP_PPPD 166
376
377 /*
378 * Juniper-private data link type, as per request from
379 * Hannes Gredler <hannes@juniper.net>. The DLT_s are used
380 * for passing on chassis-internal metainformation such as
381 * QOS profiles, cookies, etc..
382 */
383 #define LINKTYPE_JUNIPER_PPPOE 167
384 #define LINKTYPE_JUNIPER_PPPOE_ATM 168
385
386 #define LINKTYPE_GPRS_LLC 169 /* GPRS LLC */
387 #define LINKTYPE_GPF_T 170 /* GPF-T (ITU-T G.7041/Y.1303) */
388 #define LINKTYPE_GPF_F 171 /* GPF-T (ITU-T G.7041/Y.1303) */
389
390 /*
391 * Requested by Oolan Zimmer <oz@gcom.com> for use in Gcom's T1/E1 line
392 * monitoring equipment.
393 */
394 #define LINKTYPE_GCOM_T1E1 172
395 #define LINKTYPE_GCOM_SERIAL 173
396
397 /*
398 * Juniper-private data link type, as per request from
399 * Hannes Gredler <hannes@juniper.net>. The DLT_ is used
400 * for internal communication to Physical Interface Cards (PIC)
401 */
402 #define LINKTYPE_JUNIPER_PIC_PEER 174
403
404 /*
405 * Link types requested by Gregor Maier <gregor@endace.com> of Endace
406 * Measurement Systems. They add an ERF header (see
407 * http://www.endace.com/support/EndaceRecordFormat.pdf) in front of
408 * the link-layer header.
409 */
410 #define LINKTYPE_ERF_ETH 175 /* Ethernet */
411 #define LINKTYPE_ERF_POS 176 /* Packet-over-SONET */
412
413 /*
414 * Requested by Daniele Orlandi <daniele@orlandi.com> for raw LAPD
415 * for vISDN (http://www.orlandi.com/visdn/). Its link-layer header
416 * includes additional information before the LAPD header, so it's
417 * not necessarily a generic LAPD header.
418 */
419 #define LINKTYPE_LINUX_LAPD 177
420
421 /*
422 * Juniper-private data link type, as per request from
423 * Hannes Gredler <hannes@juniper.net>.
424 * The Link Types are used for prepending meta-information
425 * like interface index, interface name
426 * before standard Ethernet, PPP, Frelay & C-HDLC Frames
427 */
428 #define LINKTYPE_JUNIPER_ETHER 178
429 #define LINKTYPE_JUNIPER_PPP 179
430 #define LINKTYPE_JUNIPER_FRELAY 180
431 #define LINKTYPE_JUNIPER_CHDLC 181
432
433 /*
434 * Multi Link Frame Relay (FRF.16)
435 */
436 #define LINKTYPE_MFR 182
437
438 /*
439 * Juniper-private data link type, as per request from
440 * Hannes Gredler <hannes@juniper.net>.
441 * The DLT_ is used for internal communication with a
442 * voice Adapter Card (PIC)
443 */
444 #define LINKTYPE_JUNIPER_VP 183
445
446 /*
447 * Arinc 429 frames.
448 * DLT_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
449 * Every frame contains a 32bit A429 label.
450 * More documentation on Arinc 429 can be found at
451 * http://www.condoreng.com/support/downloads/tutorials/ARINCTutorial.pdf
452 */
453 #define LINKTYPE_A429 184
454
455 /*
456 * Arinc 653 Interpartition Communication messages.
457 * DLT_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
458 * Please refer to the A653-1 standard for more information.
459 */
460 #define LINKTYPE_A653_ICM 185
461
462 /*
463 * USB packets, beginning with a USB setup header; requested by
464 * Paolo Abeni <paolo.abeni@email.it>.
465 */
466 #define LINKTYPE_USB 186
467
468 /*
469 * Bluetooth HCI UART transport layer (part H:4); requested by
470 * Paolo Abeni.
471 */
472 #define LINKTYPE_BLUETOOTH_HCI_H4 187
473
474 /*
475 * IEEE 802.16 MAC Common Part Sublayer; requested by Maria Cruz
476 * <cruz_petagay@bah.com>.
477 */
478 #define LINKTYPE_IEEE802_16_MAC_CPS 188
479
480 /*
481 * USB packets, beginning with a Linux USB header; requested by
482 * Paolo Abeni <paolo.abeni@email.it>.
483 */
484 #define LINKTYPE_USB_LINUX 189
485
486 /*
487 * Controller Area Network (CAN) v. 2.0B packets.
488 * DLT_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
489 * Used to dump CAN packets coming from a CAN Vector board.
490 * More documentation on the CAN v2.0B frames can be found at
491 * http://www.can-cia.org/downloads/?269
492 */
493 #define LINKTYPE_CAN20B 190
494
495 /*
496 * IEEE 802.15.4, with address fields padded, as is done by Linux
497 * drivers; requested by Juergen Schimmer.
498 */
499 #define LINKTYPE_IEEE802_15_4_LINUX 191
500
501 /*
502 * Per Packet Information encapsulated packets.
503 * LINKTYPE_ requested by Gianluca Varenni <gianluca.varenni@cacetech.com>.
504 */
505 #define LINKTYPE_PPI 192
506
507 /*
508 * Header for 802.16 MAC Common Part Sublayer plus a radiotap radio header;
509 * requested by Charles Clancy.
510 */
511 #define LINKTYPE_IEEE802_16_MAC_CPS_RADIO 193
512
513 /*
514 * Juniper-private data link type, as per request from
515 * Hannes Gredler <hannes@juniper.net>.
516 * The DLT_ is used for internal communication with a
517 * integrated service module (ISM).
518 */
519 #define LINKTYPE_JUNIPER_ISM 194
520
521 /*
522 * IEEE 802.15.4, exactly as it appears in the spec (no padding, no
523 * nothing); requested by Mikko Saarnivala <mikko.saarnivala@sensinode.com>.
524 */
525 #define LINKTYPE_IEEE802_15_4 195
526
527 /*
528 * Various link-layer types, with a pseudo-header, for SITA
529 * (http://www.sita.aero/); requested by Fulko Hew (fulko.hew@gmail.com).
530 */
531 #define LINKTYPE_SITA 196
532
533 /*
534 * Various link-layer types, with a pseudo-header, for Endace DAG cards;
535 * encapsulates Endace ERF records. Requested by Stephen Donnelly
536 * <stephen@endace.com>.
537 */
538 #define LINKTYPE_ERF 197
539
540 /*
541 * Special header prepended to Ethernet packets when capturing from a
542 * u10 Networks board. Requested by Phil Mulholland
543 * <phil@u10networks.com>.
544 */
545 #define LINKTYPE_RAIF1 198
546
547 /*
548 * IPMB packet for IPMI, beginning with the I2C slave address, followed
549 * by the netFn and LUN, etc.. Requested by Chanthy Toeung
550 * <chanthy.toeung@ca.kontron.com>.
551 */
552 #define LINKTYPE_IPMB 199
553
554
555 static struct linktype_map {
556 int dlt;
557 int linktype;
558 } map[] = {
559 /*
560 * These DLT_* codes have LINKTYPE_* codes with values identical
561 * to the values of the corresponding DLT_* code.
562 */
563 { DLT_NULL, LINKTYPE_NULL },
564 { DLT_EN10MB, LINKTYPE_ETHERNET },
565 { DLT_EN3MB, LINKTYPE_EXP_ETHERNET },
566 { DLT_AX25, LINKTYPE_AX25 },
567 { DLT_PRONET, LINKTYPE_PRONET },
568 { DLT_CHAOS, LINKTYPE_CHAOS },
569 { DLT_IEEE802, LINKTYPE_TOKEN_RING },
570 { DLT_ARCNET, LINKTYPE_ARCNET },
571 { DLT_SLIP, LINKTYPE_SLIP },
572 { DLT_PPP, LINKTYPE_PPP },
573 { DLT_FDDI, LINKTYPE_FDDI },
574
575 /*
576 * These DLT_* codes have different values on different
577 * platforms; we map them to LINKTYPE_* codes that
578 * have values that should never be equal to any DLT_*
579 * code.
580 */
581 #ifdef DLT_FR
582 /* BSD/OS Frame Relay */
583 { DLT_FR, LINKTYPE_FRELAY },
584 #endif
585
586 { DLT_SYMANTEC_FIREWALL, LINKTYPE_SYMANTEC_FIREWALL },
587 { DLT_ATM_RFC1483, LINKTYPE_ATM_RFC1483 },
588 { DLT_RAW, LINKTYPE_RAW },
589 { DLT_SLIP_BSDOS, LINKTYPE_SLIP_BSDOS },
590 { DLT_PPP_BSDOS, LINKTYPE_PPP_BSDOS },
591
592 /* BSD/OS Cisco HDLC */
593 { DLT_C_HDLC, LINKTYPE_C_HDLC },
594
595 /*
596 * These DLT_* codes are not on all platforms, but, so far,
597 * there don't appear to be any platforms that define
598 * other codes with those values; we map them to
599 * different LINKTYPE_* values anyway, just in case.
600 */
601
602 /* Linux ATM Classical IP */
603 { DLT_ATM_CLIP, LINKTYPE_ATM_CLIP },
604
605 /* NetBSD sync/async serial PPP (or Cisco HDLC) */
606 { DLT_PPP_SERIAL, LINKTYPE_PPP_HDLC },
607
608 /* NetBSD PPP over Ethernet */
609 { DLT_PPP_ETHER, LINKTYPE_PPP_ETHER },
610
611 /* IEEE 802.11 wireless */
612 { DLT_IEEE802_11, LINKTYPE_IEEE802_11 },
613
614 /* Frame Relay */
615 { DLT_FRELAY, LINKTYPE_FRELAY },
616
617 /* OpenBSD loopback */
618 { DLT_LOOP, LINKTYPE_LOOP },
619
620 /* Linux cooked socket capture */
621 { DLT_LINUX_SLL, LINKTYPE_LINUX_SLL },
622
623 /* Apple LocalTalk hardware */
624 { DLT_LTALK, LINKTYPE_LTALK },
625
626 /* Acorn Econet */
627 { DLT_ECONET, LINKTYPE_ECONET },
628
629 /* OpenBSD DLT_PFLOG */
630 { DLT_PFLOG, LINKTYPE_PFLOG },
631
632 /* For Cisco-internal use */
633 { DLT_CISCO_IOS, LINKTYPE_CISCO_IOS },
634
635 /* Prism II monitor-mode header plus 802.11 header */
636 { DLT_PRISM_HEADER, LINKTYPE_PRISM_HEADER },
637
638 /* FreeBSD Aironet driver stuff */
639 { DLT_AIRONET_HEADER, LINKTYPE_AIRONET_HEADER },
640
641 /* Siemens HiPath HDLC */
642 { DLT_HHDLC, LINKTYPE_HHDLC },
643
644 /* RFC 2625 IP-over-Fibre Channel */
645 { DLT_IP_OVER_FC, LINKTYPE_IP_OVER_FC },
646
647 /* Solaris+SunATM */
648 { DLT_SUNATM, LINKTYPE_SUNATM },
649
650 /* RapidIO */
651 { DLT_RIO, LINKTYPE_RIO },
652
653 /* PCI Express */
654 { DLT_PCI_EXP, LINKTYPE_PCI_EXP },
655
656 /* Xilinx Aurora link layer */
657 { DLT_AURORA, LINKTYPE_AURORA },
658
659 /* 802.11 plus BSD radio header */
660 { DLT_IEEE802_11_RADIO, LINKTYPE_IEEE802_11_RADIO },
661
662 /* Tazmen Sniffer Protocol */
663 { DLT_TZSP, LINKTYPE_TZSP },
664
665 /* Arcnet with Linux-style link-layer headers */
666 { DLT_ARCNET_LINUX, LINKTYPE_ARCNET_LINUX },
667
668 /* Juniper-internal chassis encapsulation */
669 { DLT_JUNIPER_MLPPP, LINKTYPE_JUNIPER_MLPPP },
670 { DLT_JUNIPER_MLFR, LINKTYPE_JUNIPER_MLFR },
671 { DLT_JUNIPER_ES, LINKTYPE_JUNIPER_ES },
672 { DLT_JUNIPER_GGSN, LINKTYPE_JUNIPER_GGSN },
673 { DLT_JUNIPER_MFR, LINKTYPE_JUNIPER_MFR },
674 { DLT_JUNIPER_ATM2, LINKTYPE_JUNIPER_ATM2 },
675 { DLT_JUNIPER_SERVICES, LINKTYPE_JUNIPER_SERVICES },
676 { DLT_JUNIPER_ATM1, LINKTYPE_JUNIPER_ATM1 },
677
678 /* Apple IP-over-IEEE 1394 cooked header */
679 { DLT_APPLE_IP_OVER_IEEE1394, LINKTYPE_APPLE_IP_OVER_IEEE1394 },
680
681 /* SS7 */
682 { DLT_MTP2_WITH_PHDR, LINKTYPE_MTP2_WITH_PHDR },
683 { DLT_MTP2, LINKTYPE_MTP2 },
684 { DLT_MTP3, LINKTYPE_MTP3 },
685 { DLT_SCCP, LINKTYPE_SCCP },
686
687 /* DOCSIS MAC frames */
688 { DLT_DOCSIS, LINKTYPE_DOCSIS },
689
690 /* IrDA IrLAP packets + Linux-cooked header */
691 { DLT_LINUX_IRDA, LINKTYPE_LINUX_IRDA },
692
693 /* IBM SP and Next Federation switches */
694 { DLT_IBM_SP, LINKTYPE_IBM_SP },
695 { DLT_IBM_SN, LINKTYPE_IBM_SN },
696
697 /* 802.11 plus AVS radio header */
698 { DLT_IEEE802_11_RADIO_AVS, LINKTYPE_IEEE802_11_RADIO_AVS },
699
700 /*
701 * Any platform that defines additional DLT_* codes should:
702 *
703 * request a LINKTYPE_* code and value from tcpdump.org,
704 * as per the above;
705 *
706 * add, in their version of libpcap, an entry to map
707 * those DLT_* codes to the corresponding LINKTYPE_*
708 * code;
709 *
710 * redefine, in their "net/bpf.h", any DLT_* values
711 * that collide with the values used by their additional
712 * DLT_* codes, to remove those collisions (but without
713 * making them collide with any of the LINKTYPE_*
714 * values equal to 50 or above; they should also avoid
715 * defining DLT_* values that collide with those
716 * LINKTYPE_* values, either).
717 */
718
719 /* Juniper-internal chassis encapsulation */
720 { DLT_JUNIPER_MONITOR, LINKTYPE_JUNIPER_MONITOR },
721
722 /* BACnet MS/TP */
723 { DLT_BACNET_MS_TP, LINKTYPE_BACNET_MS_TP },
724
725 /* PPP for pppd, with direction flag in the PPP header */
726 { DLT_PPP_PPPD, LINKTYPE_PPP_PPPD},
727
728 /* Juniper-internal chassis encapsulation */
729 { DLT_JUNIPER_PPPOE, LINKTYPE_JUNIPER_PPPOE },
730 { DLT_JUNIPER_PPPOE_ATM,LINKTYPE_JUNIPER_PPPOE_ATM },
731
732 /* GPRS LLC */
733 { DLT_GPRS_LLC, LINKTYPE_GPRS_LLC },
734
735 /* Transparent Generic Framing Procedure (ITU-T G.7041/Y.1303) */
736 { DLT_GPF_T, LINKTYPE_GPF_T },
737
738 /* Framed Generic Framing Procedure (ITU-T G.7041/Y.1303) */
739 { DLT_GPF_F, LINKTYPE_GPF_F },
740
741 { DLT_GCOM_T1E1, LINKTYPE_GCOM_T1E1 },
742 { DLT_GCOM_SERIAL, LINKTYPE_GCOM_SERIAL },
743
744 /* Juniper-internal chassis encapsulation */
745 { DLT_JUNIPER_PIC_PEER, LINKTYPE_JUNIPER_PIC_PEER },
746
747 /* Endace types */
748 { DLT_ERF_ETH, LINKTYPE_ERF_ETH },
749 { DLT_ERF_POS, LINKTYPE_ERF_POS },
750
751 /* viSDN LAPD */
752 { DLT_LINUX_LAPD, LINKTYPE_LINUX_LAPD },
753
754 /* Juniper meta-information before Ether, PPP, Frame Relay, C-HDLC Frames */
755 { DLT_JUNIPER_ETHER, LINKTYPE_JUNIPER_ETHER },
756 { DLT_JUNIPER_PPP, LINKTYPE_JUNIPER_PPP },
757 { DLT_JUNIPER_FRELAY, LINKTYPE_JUNIPER_FRELAY },
758 { DLT_JUNIPER_CHDLC, LINKTYPE_JUNIPER_CHDLC },
759
760 /* Multi Link Frame Relay (FRF.16) */
761 { DLT_MFR, LINKTYPE_MFR },
762
763 /* Juniper Voice PIC */
764 { DLT_JUNIPER_VP, LINKTYPE_JUNIPER_VP },
765
766 /* Controller Area Network (CAN) v2.0B */
767 { DLT_A429, LINKTYPE_A429 },
768
769 /* Arinc 653 Interpartition Communication messages */
770 { DLT_A653_ICM, LINKTYPE_A653_ICM },
771
772 /* USB */
773 { DLT_USB, LINKTYPE_USB },
774
775 /* Bluetooth HCI UART transport layer */
776 { DLT_BLUETOOTH_HCI_H4, LINKTYPE_BLUETOOTH_HCI_H4 },
777
778 /* IEEE 802.16 MAC Common Part Sublayer */
779 { DLT_IEEE802_16_MAC_CPS, LINKTYPE_IEEE802_16_MAC_CPS },
780
781 /* USB with Linux header */
782 { DLT_USB_LINUX, LINKTYPE_USB_LINUX },
783
784 /* Controller Area Network (CAN) v2.0B */
785 { DLT_CAN20B, LINKTYPE_CAN20B },
786
787 /* IEEE 802.15.4 with address fields padded */
788 { DLT_IEEE802_15_4_LINUX, LINKTYPE_IEEE802_15_4_LINUX },
789
790 /* Per Packet Information encapsulated packets */
791 { DLT_PPI, LINKTYPE_PPI },
792
793 /* IEEE 802.16 MAC Common Part Sublayer plus radiotap header */
794 { DLT_IEEE802_16_MAC_CPS_RADIO, LINKTYPE_IEEE802_16_MAC_CPS_RADIO },
795
796 /* Juniper Voice ISM */
797 { DLT_JUNIPER_ISM, LINKTYPE_JUNIPER_ISM },
798
799 /* IEEE 802.15.4 exactly as it appears in the spec */
800 { DLT_IEEE802_15_4, LINKTYPE_IEEE802_15_4 },
801
802 /* Various link-layer types for SITA */
803 { DLT_SITA, LINKTYPE_SITA },
804
805 /* Various link-layer types for Endace */
806 { DLT_ERF, LINKTYPE_ERF },
807
808 /* Special header for u10 Networks boards */
809 { DLT_RAIF1, LINKTYPE_RAIF1 },
810
811 /* IPMB */
812 { DLT_IPMB, LINKTYPE_IPMB },
813
814 { -1, -1 }
815 };
816
817 static int
dlt_to_linktype(int dlt)818 dlt_to_linktype(int dlt)
819 {
820 int i;
821
822 for (i = 0; map[i].dlt != -1; i++) {
823 if (map[i].dlt == dlt)
824 return (map[i].linktype);
825 }
826
827 /*
828 * If we don't have a mapping for this DLT_ code, return an
829 * error; that means that the table above needs to have an
830 * entry added.
831 */
832 return (-1);
833 }
834
835 static int
linktype_to_dlt(int linktype)836 linktype_to_dlt(int linktype)
837 {
838 int i;
839
840 for (i = 0; map[i].linktype != -1; i++) {
841 if (map[i].linktype == linktype)
842 return (map[i].dlt);
843 }
844
845 /*
846 * If we don't have an entry for this link type, return
847 * the link type value; it may be a DLT_ value from an
848 * older version of libpcap.
849 */
850 return linktype;
851 }
852
853 static int
sf_write_header(FILE * fp,int linktype,int thiszone,int snaplen)854 sf_write_header(FILE *fp, int linktype, int thiszone, int snaplen)
855 {
856 struct pcap_file_header hdr;
857
858 hdr.magic = TCPDUMP_MAGIC;
859 hdr.version_major = PCAP_VERSION_MAJOR;
860 hdr.version_minor = PCAP_VERSION_MINOR;
861
862 hdr.thiszone = thiszone;
863 hdr.snaplen = snaplen;
864 hdr.sigfigs = 0;
865 hdr.linktype = linktype;
866
867 if (fwrite((char *)&hdr, sizeof(hdr), 1, fp) != 1)
868 return (-1);
869
870 return (0);
871 }
872
873 static void
swap_hdr(struct pcap_file_header * hp)874 swap_hdr(struct pcap_file_header *hp)
875 {
876 hp->version_major = SWAPSHORT(hp->version_major);
877 hp->version_minor = SWAPSHORT(hp->version_minor);
878 hp->thiszone = SWAPLONG(hp->thiszone);
879 hp->sigfigs = SWAPLONG(hp->sigfigs);
880 hp->snaplen = SWAPLONG(hp->snaplen);
881 hp->linktype = SWAPLONG(hp->linktype);
882 }
883
884 static int
sf_getnonblock(pcap_t * p,char * errbuf)885 sf_getnonblock(pcap_t *p, char *errbuf)
886 {
887 /*
888 * This is a savefile, not a live capture file, so never say
889 * it's in non-blocking mode.
890 */
891 return (0);
892 }
893
894 static int
sf_setnonblock(pcap_t * p,int nonblock,char * errbuf)895 sf_setnonblock(pcap_t *p, int nonblock, char *errbuf)
896 {
897 /*
898 * This is a savefile, not a live capture file, so ignore
899 * requests to put it in non-blocking mode.
900 */
901 return (0);
902 }
903
904 static int
sf_stats(pcap_t * p,struct pcap_stat * ps)905 sf_stats(pcap_t *p, struct pcap_stat *ps)
906 {
907 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
908 "Statistics aren't available from savefiles");
909 return (-1);
910 }
911
912 static int
sf_inject(pcap_t * p,const void * buf _U_,size_t size _U_)913 sf_inject(pcap_t *p, const void *buf _U_, size_t size _U_)
914 {
915 strlcpy(p->errbuf, "Sending packets isn't supported on savefiles",
916 PCAP_ERRBUF_SIZE);
917 return (-1);
918 }
919
920 /*
921 * Set direction flag: Which packets do we accept on a forwarding
922 * single device? IN, OUT or both?
923 */
924 static int
sf_setdirection(pcap_t * p,pcap_direction_t d)925 sf_setdirection(pcap_t *p, pcap_direction_t d)
926 {
927 snprintf(p->errbuf, sizeof(p->errbuf),
928 "Setting direction is not supported on savefiles");
929 return (-1);
930 }
931
932 static void
sf_close(pcap_t * p)933 sf_close(pcap_t *p)
934 {
935 if (p->sf.rfile != stdin)
936 (void)fclose(p->sf.rfile);
937 if (p->sf.base != NULL)
938 free(p->sf.base);
939 }
940
941 pcap_t *
pcap_open_offline(const char * fname,char * errbuf)942 pcap_open_offline(const char *fname, char *errbuf)
943 {
944 FILE *fp;
945 pcap_t *p;
946
947 if (fname[0] == '-' && fname[1] == '\0')
948 {
949 fp = stdin;
950 #if defined(WIN32) || defined(MSDOS)
951 /*
952 * We're reading from the standard input, so put it in binary
953 * mode, as savefiles are binary files.
954 */
955 SET_BINMODE(fp);
956 #endif
957 }
958 else {
959 #if !defined(WIN32) && !defined(MSDOS)
960 fp = fopen(fname, "r");
961 #else
962 fp = fopen(fname, "rb");
963 #endif
964 if (fp == NULL) {
965 snprintf(errbuf, PCAP_ERRBUF_SIZE, "%s: %s", fname,
966 pcap_strerror(errno));
967 return (NULL);
968 }
969 }
970 p = pcap_fopen_offline(fp, errbuf);
971 if (p == NULL) {
972 if (fp != stdin)
973 fclose(fp);
974 }
975 return (p);
976 }
977
978 pcap_t *
pcap_fopen_offline(FILE * fp,char * errbuf)979 pcap_fopen_offline(FILE *fp, char *errbuf)
980 {
981 register pcap_t *p;
982 struct pcap_file_header hdr;
983 size_t amt_read;
984 bpf_u_int32 magic;
985 int linklen;
986
987 p = (pcap_t *)malloc(sizeof(*p));
988 if (p == NULL) {
989 strlcpy(errbuf, "out of swap", PCAP_ERRBUF_SIZE);
990 return (NULL);
991 }
992
993 memset((char *)p, 0, sizeof(*p));
994
995 amt_read = fread((char *)&hdr, 1, sizeof(hdr), fp);
996 if (amt_read != sizeof(hdr)) {
997 if (ferror(fp)) {
998 snprintf(errbuf, PCAP_ERRBUF_SIZE,
999 "error reading dump file: %s",
1000 pcap_strerror(errno));
1001 } else {
1002 snprintf(errbuf, PCAP_ERRBUF_SIZE,
1003 "truncated dump file; tried to read %lu file header bytes, only got %lu",
1004 (unsigned long)sizeof(hdr),
1005 (unsigned long)amt_read);
1006 }
1007 goto bad;
1008 }
1009 magic = hdr.magic;
1010 if (magic != TCPDUMP_MAGIC && magic != KUZNETZOV_TCPDUMP_MAGIC) {
1011 magic = SWAPLONG(magic);
1012 if (magic != TCPDUMP_MAGIC && magic != KUZNETZOV_TCPDUMP_MAGIC) {
1013 snprintf(errbuf, PCAP_ERRBUF_SIZE,
1014 "bad dump file format");
1015 goto bad;
1016 }
1017 p->sf.swapped = 1;
1018 swap_hdr(&hdr);
1019 }
1020 if (magic == KUZNETZOV_TCPDUMP_MAGIC) {
1021 /*
1022 * XXX - the patch that's in some versions of libpcap
1023 * changes the packet header but not the magic number,
1024 * and some other versions with this magic number have
1025 * some extra debugging information in the packet header;
1026 * we'd have to use some hacks^H^H^H^H^Hheuristics to
1027 * detect those variants.
1028 *
1029 * Ethereal does that, but it does so by trying to read
1030 * the first two packets of the file with each of the
1031 * record header formats. That currently means it seeks
1032 * backwards and retries the reads, which doesn't work
1033 * on pipes. We want to be able to read from a pipe, so
1034 * that strategy won't work; we'd have to buffer some
1035 * data ourselves and read from that buffer in order to
1036 * make that work.
1037 */
1038 p->sf.hdrsize = sizeof(struct pcap_sf_patched_pkthdr);
1039 } else
1040 p->sf.hdrsize = sizeof(struct pcap_sf_pkthdr);
1041 if (hdr.version_major < PCAP_VERSION_MAJOR) {
1042 snprintf(errbuf, PCAP_ERRBUF_SIZE, "archaic file format");
1043 goto bad;
1044 }
1045 p->tzoff = hdr.thiszone;
1046 p->snapshot = hdr.snaplen;
1047 p->linktype = linktype_to_dlt(hdr.linktype);
1048 if (magic == KUZNETZOV_TCPDUMP_MAGIC && p->linktype == DLT_EN10MB) {
1049 /*
1050 * This capture might have been done in raw mode or cooked
1051 * mode.
1052 *
1053 * If it was done in cooked mode, p->snapshot was passed
1054 * to recvfrom() as the buffer size, meaning that the
1055 * most packet data that would be copied would be
1056 * p->snapshot. However, a faked Ethernet header would
1057 * then have been added to it, so the most data that would
1058 * be in a packet in the file would be p->snapshot + 14.
1059 *
1060 * We can't easily tell whether the capture was done in
1061 * raw mode or cooked mode, so we'll assume it was
1062 * cooked mode, and add 14 to the snapshot length. That
1063 * means that, for a raw capture, the snapshot length will
1064 * be misleading if you use it to figure out why a capture
1065 * doesn't have all the packet data, but there's not much
1066 * we can do to avoid that.
1067 */
1068 p->snapshot += 14;
1069 }
1070 p->sf.rfile = fp;
1071 #ifndef WIN32
1072 p->bufsize = hdr.snaplen;
1073 #else
1074 /* Allocate the space for pcap_pkthdr as well. It will be used by pcap_read_ex */
1075 p->bufsize = hdr.snaplen+sizeof(struct pcap_pkthdr);
1076 #endif
1077
1078 /* Align link header as required for proper data alignment */
1079 /* XXX should handle all types */
1080 switch (p->linktype) {
1081
1082 case DLT_EN10MB:
1083 linklen = 14;
1084 break;
1085
1086 case DLT_FDDI:
1087 linklen = 13 + 8; /* fddi_header + llc */
1088 break;
1089
1090 case DLT_NULL:
1091 default:
1092 linklen = 0;
1093 break;
1094 }
1095
1096 if (p->bufsize < 0)
1097 p->bufsize = BPF_MAXBUFSIZE;
1098 p->sf.base = (u_char *)malloc(p->bufsize + BPF_ALIGNMENT);
1099 if (p->sf.base == NULL) {
1100 strlcpy(errbuf, "out of swap", PCAP_ERRBUF_SIZE);
1101 goto bad;
1102 }
1103 p->buffer = p->sf.base + BPF_ALIGNMENT - (linklen % BPF_ALIGNMENT);
1104 p->sf.version_major = hdr.version_major;
1105 p->sf.version_minor = hdr.version_minor;
1106 #ifdef PCAP_FDDIPAD
1107 /* Padding only needed for live capture fcode */
1108 p->fddipad = 0;
1109 #endif
1110
1111 /*
1112 * We interchanged the caplen and len fields at version 2.3,
1113 * in order to match the bpf header layout. But unfortunately
1114 * some files were written with version 2.3 in their headers
1115 * but without the interchanged fields.
1116 *
1117 * In addition, DG/UX tcpdump writes out files with a version
1118 * number of 543.0, and with the caplen and len fields in the
1119 * pre-2.3 order.
1120 */
1121 switch (hdr.version_major) {
1122
1123 case 2:
1124 if (hdr.version_minor < 3)
1125 p->sf.lengths_swapped = SWAPPED;
1126 else if (hdr.version_minor == 3)
1127 p->sf.lengths_swapped = MAYBE_SWAPPED;
1128 else
1129 p->sf.lengths_swapped = NOT_SWAPPED;
1130 break;
1131
1132 case 543:
1133 p->sf.lengths_swapped = SWAPPED;
1134 break;
1135
1136 default:
1137 p->sf.lengths_swapped = NOT_SWAPPED;
1138 break;
1139 }
1140
1141 #if !defined(WIN32) && !defined(MSDOS)
1142 /*
1143 * You can do "select()" and "poll()" on plain files on most
1144 * platforms, and should be able to do so on pipes.
1145 *
1146 * You can't do "select()" on anything other than sockets in
1147 * Windows, so, on Win32 systems, we don't have "selectable_fd".
1148 */
1149 p->selectable_fd = fileno(fp);
1150 #endif
1151
1152 p->read_op = pcap_offline_read;
1153 p->inject_op = sf_inject;
1154 p->setfilter_op = install_bpf_program;
1155 p->setdirection_op = sf_setdirection;
1156 p->set_datalink_op = NULL; /* we don't support munging link-layer headers */
1157 p->getnonblock_op = sf_getnonblock;
1158 p->setnonblock_op = sf_setnonblock;
1159 p->stats_op = sf_stats;
1160 p->close_op = sf_close;
1161
1162 return (p);
1163 bad:
1164 free(p);
1165 return (NULL);
1166 }
1167
1168 /*
1169 * Read sf_readfile and return the next packet. Return the header in hdr
1170 * and the contents in buf. Return 0 on success, SFERR_EOF if there were
1171 * no more packets, and SFERR_TRUNC if a partial packet was encountered.
1172 */
1173 static int
sf_next_packet(pcap_t * p,struct pcap_pkthdr * hdr,u_char * buf,u_int buflen)1174 sf_next_packet(pcap_t *p, struct pcap_pkthdr *hdr, u_char *buf, u_int buflen)
1175 {
1176 struct pcap_sf_patched_pkthdr sf_hdr;
1177 FILE *fp = p->sf.rfile;
1178 size_t amt_read;
1179 bpf_u_int32 t;
1180
1181 /*
1182 * Read the packet header; the structure we use as a buffer
1183 * is the longer structure for files generated by the patched
1184 * libpcap, but if the file has the magic number for an
1185 * unpatched libpcap we only read as many bytes as the regular
1186 * header has.
1187 */
1188 amt_read = fread(&sf_hdr, 1, p->sf.hdrsize, fp);
1189 if (amt_read != p->sf.hdrsize) {
1190 if (ferror(fp)) {
1191 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1192 "error reading dump file: %s",
1193 pcap_strerror(errno));
1194 return (-1);
1195 } else {
1196 if (amt_read != 0) {
1197 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1198 "truncated dump file; tried to read %d header bytes, only got %lu",
1199 p->sf.hdrsize, (unsigned long)amt_read);
1200 return (-1);
1201 }
1202 /* EOF */
1203 return (1);
1204 }
1205 }
1206
1207 if (p->sf.swapped) {
1208 /* these were written in opposite byte order */
1209 hdr->caplen = SWAPLONG(sf_hdr.caplen);
1210 hdr->len = SWAPLONG(sf_hdr.len);
1211 hdr->ts.tv_sec = SWAPLONG(sf_hdr.ts.tv_sec);
1212 hdr->ts.tv_usec = SWAPLONG(sf_hdr.ts.tv_usec);
1213 } else {
1214 hdr->caplen = sf_hdr.caplen;
1215 hdr->len = sf_hdr.len;
1216 hdr->ts.tv_sec = sf_hdr.ts.tv_sec;
1217 hdr->ts.tv_usec = sf_hdr.ts.tv_usec;
1218 }
1219 /* Swap the caplen and len fields, if necessary. */
1220 switch (p->sf.lengths_swapped) {
1221
1222 case NOT_SWAPPED:
1223 break;
1224
1225 case MAYBE_SWAPPED:
1226 if (hdr->caplen <= hdr->len) {
1227 /*
1228 * The captured length is <= the actual length,
1229 * so presumably they weren't swapped.
1230 */
1231 break;
1232 }
1233 /* FALLTHROUGH */
1234
1235 case SWAPPED:
1236 t = hdr->caplen;
1237 hdr->caplen = hdr->len;
1238 hdr->len = t;
1239 break;
1240 }
1241
1242 if (hdr->caplen > buflen) {
1243 /*
1244 * This can happen due to Solaris 2.3 systems tripping
1245 * over the BUFMOD problem and not setting the snapshot
1246 * correctly in the savefile header. If the caplen isn't
1247 * grossly wrong, try to salvage.
1248 */
1249 static u_char *tp = NULL;
1250 static size_t tsize = 0;
1251
1252 if (hdr->caplen > 65535) {
1253 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1254 "bogus savefile header");
1255 return (-1);
1256 }
1257
1258 if (tsize < hdr->caplen) {
1259 tsize = ((hdr->caplen + 1023) / 1024) * 1024;
1260 if (tp != NULL)
1261 free((u_char *)tp);
1262 tp = (u_char *)malloc(tsize);
1263 if (tp == NULL) {
1264 tsize = 0;
1265 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1266 "BUFMOD hack malloc");
1267 return (-1);
1268 }
1269 }
1270 amt_read = fread((char *)tp, 1, hdr->caplen, fp);
1271 if (amt_read != hdr->caplen) {
1272 if (ferror(fp)) {
1273 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1274 "error reading dump file: %s",
1275 pcap_strerror(errno));
1276 } else {
1277 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1278 "truncated dump file; tried to read %u captured bytes, only got %lu",
1279 hdr->caplen, (unsigned long)amt_read);
1280 }
1281 return (-1);
1282 }
1283 /*
1284 * We can only keep up to buflen bytes. Since caplen > buflen
1285 * is exactly how we got here, we know we can only keep the
1286 * first buflen bytes and must drop the remainder. Adjust
1287 * caplen accordingly, so we don't get confused later as
1288 * to how many bytes we have to play with.
1289 */
1290 hdr->caplen = buflen;
1291 memcpy((char *)buf, (char *)tp, buflen);
1292
1293 } else {
1294 /* read the packet itself */
1295 amt_read = fread((char *)buf, 1, hdr->caplen, fp);
1296 if (amt_read != hdr->caplen) {
1297 if (ferror(fp)) {
1298 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1299 "error reading dump file: %s",
1300 pcap_strerror(errno));
1301 } else {
1302 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1303 "truncated dump file; tried to read %u captured bytes, only got %lu",
1304 hdr->caplen, (unsigned long)amt_read);
1305 }
1306 return (-1);
1307 }
1308 }
1309 return (0);
1310 }
1311
1312 /*
1313 * Print out packets stored in the file initialized by sf_read_init().
1314 * If cnt > 0, return after 'cnt' packets, otherwise continue until eof.
1315 */
1316 int
pcap_offline_read(pcap_t * p,int cnt,pcap_handler callback,u_char * user)1317 pcap_offline_read(pcap_t *p, int cnt, pcap_handler callback, u_char *user)
1318 {
1319 struct bpf_insn *fcode;
1320 int status = 0;
1321 int n = 0;
1322
1323 while (status == 0) {
1324 struct pcap_pkthdr h;
1325
1326 /*
1327 * Has "pcap_breakloop()" been called?
1328 * If so, return immediately - if we haven't read any
1329 * packets, clear the flag and return -2 to indicate
1330 * that we were told to break out of the loop, otherwise
1331 * leave the flag set, so that the *next* call will break
1332 * out of the loop without having read any packets, and
1333 * return the number of packets we've processed so far.
1334 */
1335 if (p->break_loop) {
1336 if (n == 0) {
1337 p->break_loop = 0;
1338 return (-2);
1339 } else
1340 return (n);
1341 }
1342
1343 status = sf_next_packet(p, &h, p->buffer, p->bufsize);
1344 if (status) {
1345 if (status == 1)
1346 return (0);
1347 return (status);
1348 }
1349
1350 if ((fcode = p->fcode.bf_insns) == NULL ||
1351 bpf_filter(fcode, p->buffer, h.len, h.caplen)) {
1352 (*callback)(user, &h, p->buffer);
1353 if (++n >= cnt && cnt > 0)
1354 break;
1355 }
1356 }
1357 /*XXX this breaks semantics tcpslice expects */
1358 return (n);
1359 }
1360
1361 /*
1362 * Output a packet to the initialized dump file.
1363 */
1364 void
pcap_dump(u_char * user,const struct pcap_pkthdr * h,const u_char * sp)1365 pcap_dump(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1366 {
1367 register FILE *f;
1368 struct pcap_sf_pkthdr sf_hdr;
1369
1370 f = (FILE *)user;
1371 sf_hdr.ts.tv_sec = h->ts.tv_sec;
1372 sf_hdr.ts.tv_usec = h->ts.tv_usec;
1373 sf_hdr.caplen = h->caplen;
1374 sf_hdr.len = h->len;
1375 /* XXX we should check the return status */
1376 (void)fwrite(&sf_hdr, sizeof(sf_hdr), 1, f);
1377 (void)fwrite(sp, h->caplen, 1, f);
1378 }
1379
1380 static pcap_dumper_t *
pcap_setup_dump(pcap_t * p,int linktype,FILE * f,const char * fname)1381 pcap_setup_dump(pcap_t *p, int linktype, FILE *f, const char *fname)
1382 {
1383
1384 #if defined(WIN32) || defined(MSDOS)
1385 /*
1386 * If we're writing to the standard output, put it in binary
1387 * mode, as savefiles are binary files.
1388 *
1389 * Otherwise, we turn off buffering.
1390 * XXX - why? And why not on the standard output?
1391 */
1392 if (f == stdout)
1393 SET_BINMODE(f);
1394 else
1395 setbuf(f, NULL);
1396 #endif
1397 if (sf_write_header(f, linktype, p->tzoff, p->snapshot) == -1) {
1398 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "Can't write to %s: %s",
1399 fname, pcap_strerror(errno));
1400 if (f != stdout)
1401 (void)fclose(f);
1402 return (NULL);
1403 }
1404 return ((pcap_dumper_t *)f);
1405 }
1406
1407 /*
1408 * Initialize so that sf_write() will output to the file named 'fname'.
1409 */
1410 pcap_dumper_t *
pcap_dump_open(pcap_t * p,const char * fname)1411 pcap_dump_open(pcap_t *p, const char *fname)
1412 {
1413 FILE *f;
1414 int linktype;
1415
1416 linktype = dlt_to_linktype(p->linktype);
1417 if (linktype == -1) {
1418 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1419 "%s: link-layer type %d isn't supported in savefiles",
1420 fname, linktype);
1421 return (NULL);
1422 }
1423
1424 if (fname[0] == '-' && fname[1] == '\0') {
1425 f = stdout;
1426 fname = "standard output";
1427 } else {
1428 #if !defined(WIN32) && !defined(MSDOS)
1429 f = fopen(fname, "w");
1430 #else
1431 f = fopen(fname, "wb");
1432 #endif
1433 if (f == NULL) {
1434 snprintf(p->errbuf, PCAP_ERRBUF_SIZE, "%s: %s",
1435 fname, pcap_strerror(errno));
1436 return (NULL);
1437 }
1438 }
1439 return (pcap_setup_dump(p, linktype, f, fname));
1440 }
1441
1442 /*
1443 * Initialize so that sf_write() will output to the given stream.
1444 */
1445 pcap_dumper_t *
pcap_dump_fopen(pcap_t * p,FILE * f)1446 pcap_dump_fopen(pcap_t *p, FILE *f)
1447 {
1448 int linktype;
1449
1450 linktype = dlt_to_linktype(p->linktype);
1451 if (linktype == -1) {
1452 snprintf(p->errbuf, PCAP_ERRBUF_SIZE,
1453 "stream: link-layer type %d isn't supported in savefiles",
1454 linktype);
1455 return (NULL);
1456 }
1457
1458 return (pcap_setup_dump(p, linktype, f, "stream"));
1459 }
1460
1461 FILE *
pcap_dump_file(pcap_dumper_t * p)1462 pcap_dump_file(pcap_dumper_t *p)
1463 {
1464 return ((FILE *)p);
1465 }
1466
1467 long
pcap_dump_ftell(pcap_dumper_t * p)1468 pcap_dump_ftell(pcap_dumper_t *p)
1469 {
1470 return (ftell((FILE *)p));
1471 }
1472
1473 int
pcap_dump_flush(pcap_dumper_t * p)1474 pcap_dump_flush(pcap_dumper_t *p)
1475 {
1476
1477 if (fflush((FILE *)p) == EOF)
1478 return (-1);
1479 else
1480 return (0);
1481 }
1482
1483 void
pcap_dump_close(pcap_dumper_t * p)1484 pcap_dump_close(pcap_dumper_t *p)
1485 {
1486
1487 #ifdef notyet
1488 if (ferror((FILE *)p))
1489 return-an-error;
1490 /* XXX should check return from fclose() too */
1491 #endif
1492 (void)fclose((FILE *)p);
1493 }
1494