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1 /*
2 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
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 * Support for splitting captures into multiple files with a maximum
22 * file size:
23 *
24 * Copyright (c) 2001
25 * Seth Webster <swebster@sst.ll.mit.edu>
26 */
27
28 #ifndef lint
29 static const char copyright[] _U_ =
30 "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
31 The Regents of the University of California. All rights reserved.\n";
32 static const char rcsid[] _U_ =
33 "@(#) $Header: /tcpdump/master/tcpdump/tcpdump.c,v 1.216.2.7 2004-01-14 03:25:28 guy Exp $ (LBL)";
34 #endif
35
36 /*
37 * tcpdump - monitor tcp/ip traffic on an ethernet.
38 *
39 * First written in 1987 by Van Jacobson, Lawrence Berkeley Laboratory.
40 * Mercilessly hacked and occasionally improved since then via the
41 * combined efforts of Van, Steve McCanne and Craig Leres of LBL.
42 */
43
44 #ifdef HAVE_CONFIG_H
45 #include "config.h"
46 #endif
47
48 #include <tcpdump-stdinc.h>
49
50 #ifdef WIN32
51 #include "getopt.h"
52 #include "w32_fzs.h"
53 extern int strcasecmp (const char *__s1, const char *__s2);
54 extern int SIZE_BUF;
55 #define off_t long
56 #define uint UINT
57 #endif /* WIN32 */
58
59 #include <pcap.h>
60 #include <signal.h>
61 #include <stdio.h>
62 #include <stdlib.h>
63 #include <string.h>
64
65 #include "interface.h"
66 #include "addrtoname.h"
67 #include "machdep.h"
68 #include "setsignal.h"
69 #include "gmt2local.h"
70 #include "pcap-missing.h"
71
72 int dflag; /* print filter code */
73 int eflag; /* print ethernet header */
74 int fflag; /* don't translate "foreign" IP address */
75 int Lflag; /* list available data link types and exit */
76 int nflag; /* leave addresses as numbers */
77 int Nflag; /* remove domains from printed host names */
78 int Oflag = 1; /* run filter code optimizer */
79 int pflag; /* don't go promiscuous */
80 int qflag; /* quick (shorter) output */
81 int Rflag = 1; /* print sequence # field in AH/ESP*/
82 int sflag = 0; /* use the libsmi to translate OIDs */
83 int Sflag; /* print raw TCP sequence numbers */
84 int tflag = 1; /* print packet arrival time */
85 int Uflag = 0; /* "unbuffered" output of dump files */
86 int uflag = 0; /* Print undecoded NFS handles */
87 int vflag; /* verbose */
88 int xflag; /* print packet in hex */
89 int Xflag; /* print packet in ascii as well as hex */
90 off_t Cflag = 0; /* rotate dump files after this many bytes */
91 int Aflag = 0; /* print packet only in ascii observing LF, CR, TAB, SPACE */
92 int dlt = -1; /* if != -1, ask libpcap for the DLT it names */
93
94 const char *dlt_name = NULL;
95
96 char *espsecret = NULL; /* ESP secret key */
97
98 int packettype;
99
100 static int infodelay;
101 static int infoprint;
102
103 char *program_name;
104
105 int32_t thiszone; /* seconds offset from gmt to local time */
106
107 /* Forwards */
108 static RETSIGTYPE cleanup(int);
109 static void usage(void) __attribute__((noreturn));
110 static void show_dlts_and_exit(pcap_t *pd) __attribute__((noreturn));
111
112 static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
113 static void dump_packet_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *);
114 static void dump_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
115
116 #ifdef SIGINFO
117 RETSIGTYPE requestinfo(int);
118 #endif
119
120 static void info(int);
121 static u_int packets_captured;
122
123 /* Length of saved portion of packet. */
124 int snaplen = DEFAULT_SNAPLEN;
125
126 typedef u_int (*if_printer)(const struct pcap_pkthdr *, const u_char *);
127
128 struct printer {
129 if_printer f;
130 int type;
131 };
132
133 static struct printer printers[] = {
134 { arcnet_if_print, DLT_ARCNET },
135 #ifdef DLT_ARCNET_LINUX
136 { arcnet_linux_if_print, DLT_ARCNET_LINUX },
137 #endif
138 { ether_if_print, DLT_EN10MB },
139 { token_if_print, DLT_IEEE802 },
140 #ifdef DLT_LANE8023
141 { lane_if_print, DLT_LANE8023 },
142 #endif
143 #ifdef DLT_CIP
144 { cip_if_print, DLT_CIP },
145 #endif
146 #ifdef DLT_ATM_CLIP
147 { cip_if_print, DLT_ATM_CLIP },
148 #endif
149 { sl_if_print, DLT_SLIP },
150 #ifdef DLT_SLIP_BSDOS
151 { sl_bsdos_if_print, DLT_SLIP_BSDOS },
152 #endif
153 { ppp_if_print, DLT_PPP },
154 #ifdef DLT_PPP_BSDOS
155 { ppp_bsdos_if_print, DLT_PPP_BSDOS },
156 #endif
157 { fddi_if_print, DLT_FDDI },
158 { null_if_print, DLT_NULL },
159 #ifdef DLT_LOOP
160 { null_if_print, DLT_LOOP },
161 #endif
162 { raw_if_print, DLT_RAW },
163 { atm_if_print, DLT_ATM_RFC1483 },
164 #ifdef DLT_C_HDLC
165 { chdlc_if_print, DLT_C_HDLC },
166 #endif
167 #ifdef DLT_HDLC
168 { chdlc_if_print, DLT_HDLC },
169 #endif
170 #ifdef DLT_PPP_SERIAL
171 { ppp_hdlc_if_print, DLT_PPP_SERIAL },
172 #endif
173 #ifdef DLT_PPP_ETHER
174 { pppoe_if_print, DLT_PPP_ETHER },
175 #endif
176 #ifdef DLT_LINUX_SLL
177 { sll_if_print, DLT_LINUX_SLL },
178 #endif
179 #ifdef DLT_IEEE802_11
180 { ieee802_11_if_print, DLT_IEEE802_11},
181 #endif
182 #ifdef DLT_LTALK
183 { ltalk_if_print, DLT_LTALK },
184 #endif
185 #ifdef DLT_PFLOG
186 { pflog_if_print, DLT_PFLOG },
187 #endif
188 #ifdef DLT_FR
189 { fr_if_print, DLT_FR },
190 #endif
191 #ifdef DLT_FRELAY
192 { fr_if_print, DLT_FRELAY },
193 #endif
194 #ifdef DLT_SUNATM
195 { sunatm_if_print, DLT_SUNATM },
196 #endif
197 #ifdef DLT_IP_OVER_FC
198 { ipfc_if_print, DLT_IP_OVER_FC },
199 #endif
200 #ifdef DLT_PRISM_HEADER
201 { prism_if_print, DLT_PRISM_HEADER },
202 #endif
203 #ifdef DLT_IEEE802_11_RADIO
204 { ieee802_11_radio_if_print, DLT_IEEE802_11_RADIO },
205 #endif
206 #ifdef DLT_ENC
207 { enc_if_print, DLT_ENC },
208 #endif
209 { NULL, 0 },
210 };
211
212 static if_printer
213 lookup_printer(int type)
214 {
215 struct printer *p;
216
217 for (p = printers; p->f; ++p)
218 if (type == p->type)
219 return p->f;
220
221 return NULL;
222 /* NOTREACHED */
223 }
224
225 static pcap_t *pd;
226
227 extern int optind;
228 extern int opterr;
229 extern char *optarg;
230
231 struct print_info {
232 if_printer printer;
233 };
234
235 struct dump_info {
236 char *WFileName;
237 pcap_t *pd;
238 pcap_dumper_t *p;
239 };
240
241 static void
242 show_dlts_and_exit(pcap_t *pd)
243 {
244 int n_dlts;
245 int *dlts = 0;
246 const char *dlt_name;
247
248 n_dlts = pcap_list_datalinks(pd, &dlts);
249 if (n_dlts < 0)
250 error("%s", pcap_geterr(pd));
251 else if (n_dlts == 0 || !dlts)
252 error("No data link types.");
253
254 (void) fprintf(stderr, "Data link types (use option -y to set):\n");
255
256 while (--n_dlts >= 0) {
257 dlt_name = pcap_datalink_val_to_name(dlts[n_dlts]);
258 if (dlt_name != NULL) {
259 (void) fprintf(stderr, " %s (%s)", dlt_name,
260 pcap_datalink_val_to_description(dlts[n_dlts]));
261
262 /*
263 * OK, does tcpdump handle that type?
264 */
265 if (lookup_printer(dlts[n_dlts]) == NULL)
266 (void) fprintf(stderr, " (not supported)");
267 putchar('\n');
268 } else {
269 (void) fprintf(stderr, " DLT %d (not supported)\n",
270 dlts[n_dlts]);
271 }
272 }
273 free(dlts);
274 exit(0);
275 }
276
277 /*
278 * Set up flags that might or might not be supported depending on the
279 * version of libpcap we're using.
280 */
281 #ifdef WIN32
282 #define B_FLAG "B:"
283 #define B_FLAG_USAGE " [ -B size ]"
284 #else /* WIN32 */
285 #define B_FLAG
286 #define B_FLAG_USAGE
287 #endif /* WIN32 */
288
289 #ifdef HAVE_PCAP_FINDALLDEVS
290 #define D_FLAG "D"
291 #else
292 #define D_FLAG
293 #endif
294
295 #ifdef HAVE_PCAP_DUMP_FLUSH
296 #define U_FLAG "U"
297 #else
298 #define U_FLAG
299 #endif
300
301 int
302 main(int argc, char **argv)
303 {
304 register int cnt, op, i;
305 bpf_u_int32 localnet, netmask;
306 register char *cp, *infile, *cmdbuf, *device, *RFileName, *WFileName;
307 pcap_handler callback;
308 int type;
309 struct bpf_program fcode;
310 #ifndef WIN32
311 RETSIGTYPE (*oldhandler)(int);
312 #endif
313 struct print_info printinfo;
314 struct dump_info dumpinfo;
315 u_char *pcap_userdata;
316 char ebuf[PCAP_ERRBUF_SIZE];
317 #ifdef HAVE_PCAP_FINDALLDEVS
318 pcap_if_t *devpointer;
319 int devnum;
320 #endif
321 int status;
322 #ifdef WIN32
323 u_int UserBufferSize = 1000000;
324 if(wsockinit() != 0) return 1;
325 #endif /* WIN32 */
326
327 cnt = -1;
328 device = NULL;
329 infile = NULL;
330 RFileName = NULL;
331 WFileName = NULL;
332 if ((cp = strrchr(argv[0], '/')) != NULL)
333 program_name = cp + 1;
334 else
335 program_name = argv[0];
336
337 if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
338 error("%s", ebuf);
339
340 #ifdef LIBSMI
341 smiInit("tcpdump");
342 #endif
343
344 opterr = 0;
345 while (
346 (op = getopt(argc, argv, "aA" B_FLAG "c:C:d" D_FLAG "eE:fF:i:lLm:nNOpqr:Rs:StT:u" U_FLAG "vw:xXy:Y")) != -1)
347 switch (op) {
348
349 case 'a':
350 /* compatibility for old -a */
351 break;
352
353 case 'A':
354 ++xflag;
355 ++Xflag;
356 ++Aflag;
357 break;
358
359 #ifdef WIN32
360 case 'B':
361 UserBufferSize = atoi(optarg)*1024;
362 if (UserBufferSize < 0)
363 error("invalid packet buffer size %s", optarg);
364 break;
365 #endif /* WIN32 */
366
367 case 'c':
368 cnt = atoi(optarg);
369 if (cnt <= 0)
370 error("invalid packet count %s", optarg);
371 break;
372
373 case 'C':
374 Cflag = atoi(optarg) * 1000000;
375 if (Cflag < 0)
376 error("invalid file size %s", optarg);
377 break;
378
379 case 'd':
380 ++dflag;
381 break;
382
383 #ifdef HAVE_PCAP_FINDALLDEVS
384 case 'D':
385 if (pcap_findalldevs(&devpointer, ebuf) < 0)
386 error("%s", ebuf);
387 else {
388 for (i = 0; devpointer != 0; i++) {
389 printf("%d.%s", i+1, devpointer->name);
390 if (devpointer->description != NULL)
391 printf(" (%s)", devpointer->description);
392 printf("\n");
393 devpointer = devpointer->next;
394 }
395 }
396 return 0;
397 #endif /* HAVE_PCAP_FINDALLDEVS */
398
399 case 'L':
400 Lflag++;
401 break;
402
403 case 'e':
404 ++eflag;
405 break;
406
407 case 'E':
408 #ifndef HAVE_LIBCRYPTO
409 warning("crypto code not compiled in");
410 #endif
411 espsecret = optarg;
412 break;
413
414 case 'f':
415 ++fflag;
416 break;
417
418 case 'F':
419 infile = optarg;
420 break;
421
422 case 'i':
423 if (optarg[0] == '0' && optarg[1] == 0)
424 error("Invalid adapter index");
425
426 #ifdef HAVE_PCAP_FINDALLDEVS
427 /*
428 * If the argument is a number, treat it as
429 * an index into the list of adapters, as
430 * printed by "tcpdump -D".
431 *
432 * This should be OK on UNIX systems, as interfaces
433 * shouldn't have names that begin with digits.
434 * It can be useful on Windows, where more than
435 * one interface can have the same name.
436 */
437 if ((devnum = atoi(optarg)) != 0) {
438 if (devnum < 0)
439 error("Invalid adapter index");
440
441 if (pcap_findalldevs(&devpointer, ebuf) < 0)
442 error("%s", ebuf);
443 else {
444 for (i = 0; i < devnum-1; i++){
445 devpointer = devpointer->next;
446 if (devpointer == NULL)
447 error("Invalid adapter index");
448 }
449 }
450 device = devpointer->name;
451 break;
452 }
453 #endif /* HAVE_PCAP_FINDALLDEVS */
454 device = optarg;
455 break;
456
457 case 'l':
458 #ifdef WIN32
459 /*
460 * _IOLBF is the same as _IOFBF in Microsoft's C
461 * libraries; the only alternative they offer
462 * is _IONBF.
463 *
464 * XXX - this should really be checking for MSVC++,
465 * not WIN32, if, for example, MinGW has its own
466 * C library that is more UNIX-compatible.
467 */
468 setvbuf(stdout, NULL, _IONBF, 0);
469 #else /* WIN32 */
470 #ifdef HAVE_SETLINEBUF
471 setlinebuf(stdout);
472 #else
473 setvbuf(stdout, NULL, _IOLBF, 0);
474 #endif
475 #endif /* WIN32 */
476 break;
477
478 case 'n':
479 ++nflag;
480 break;
481
482 case 'N':
483 ++Nflag;
484 break;
485
486 case 'm':
487 #ifdef LIBSMI
488 if (smiLoadModule(optarg) == 0) {
489 error("could not load MIB module %s", optarg);
490 }
491 sflag = 1;
492 #else
493 (void)fprintf(stderr, "%s: ignoring option `-m %s' ",
494 program_name, optarg);
495 (void)fprintf(stderr, "(no libsmi support)\n");
496 #endif
497 break;
498
499 case 'O':
500 Oflag = 0;
501 break;
502
503 case 'p':
504 ++pflag;
505 break;
506
507 case 'q':
508 ++qflag;
509 break;
510
511 case 'r':
512 RFileName = optarg;
513 break;
514
515 case 'R':
516 Rflag = 0;
517 break;
518
519 case 's': {
520 char *end;
521
522 snaplen = strtol(optarg, &end, 0);
523 if (optarg == end || *end != '\0'
524 || snaplen < 0 || snaplen > 65535)
525 error("invalid snaplen %s", optarg);
526 else if (snaplen == 0)
527 snaplen = 65535;
528 break;
529 }
530
531 case 'S':
532 ++Sflag;
533 break;
534
535 case 't':
536 --tflag;
537 break;
538
539 case 'T':
540 if (strcasecmp(optarg, "vat") == 0)
541 packettype = PT_VAT;
542 else if (strcasecmp(optarg, "wb") == 0)
543 packettype = PT_WB;
544 else if (strcasecmp(optarg, "rpc") == 0)
545 packettype = PT_RPC;
546 else if (strcasecmp(optarg, "rtp") == 0)
547 packettype = PT_RTP;
548 else if (strcasecmp(optarg, "rtcp") == 0)
549 packettype = PT_RTCP;
550 else if (strcasecmp(optarg, "snmp") == 0)
551 packettype = PT_SNMP;
552 else if (strcasecmp(optarg, "cnfp") == 0)
553 packettype = PT_CNFP;
554 else if (strcasecmp(optarg, "tftp") == 0)
555 packettype = PT_TFTP;
556 else if (strcasecmp(optarg, "aodv") == 0)
557 packettype = PT_AODV;
558 else
559 error("unknown packet type `%s'", optarg);
560 break;
561
562 case 'u':
563 ++uflag;
564 break;
565
566 #ifdef HAVE_PCAP_DUMP_FLUSH
567 case 'U':
568 ++Uflag;
569 break;
570 #endif
571
572 case 'v':
573 ++vflag;
574 break;
575
576 case 'w':
577 WFileName = optarg;
578 break;
579
580 case 'x':
581 ++xflag;
582 break;
583
584 case 'X':
585 ++xflag;
586 ++Xflag;
587 break;
588
589 case 'y':
590 dlt_name = optarg;
591 dlt = pcap_datalink_name_to_val(dlt_name);
592 if (dlt < 0)
593 error("invalid data link type %s", dlt_name);
594 break;
595
596 #if defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG)
597 case 'Y':
598 {
599 /* Undocumented flag */
600 #ifdef HAVE_PCAP_DEBUG
601 extern int pcap_debug;
602 pcap_debug = 1;
603 #else
604 extern int yydebug;
605 yydebug = 1;
606 #endif
607 }
608 break;
609 #endif
610 default:
611 usage();
612 /* NOTREACHED */
613 }
614
615 if (tflag > 0)
616 thiszone = gmt2local(0);
617
618 if (RFileName != NULL) {
619 int dlt;
620 const char *dlt_name;
621
622 #ifndef WIN32
623 /*
624 * We don't need network access, so relinquish any set-UID
625 * or set-GID privileges we have (if any).
626 *
627 * We do *not* want set-UID privileges when opening a
628 * trace file, as that might let the user read other
629 * people's trace files (especially if we're set-UID
630 * root).
631 */
632 setuid(getuid());
633 #endif /* WIN32 */
634 pd = pcap_open_offline(RFileName, ebuf);
635 if (pd == NULL)
636 error("%s", ebuf);
637 dlt = pcap_datalink(pd);
638 dlt_name = pcap_datalink_val_to_name(dlt);
639 if (dlt_name == NULL) {
640 fprintf(stderr, "reading from file %s, link-type %u\n",
641 RFileName, dlt);
642 } else {
643 fprintf(stderr,
644 "reading from file %s, link-type %s (%s)\n",
645 RFileName, dlt_name,
646 pcap_datalink_val_to_description(dlt));
647 }
648 localnet = 0;
649 netmask = 0;
650 if (fflag != 0)
651 error("-f and -r options are incompatible");
652 } else {
653 if (device == NULL) {
654 device = pcap_lookupdev(ebuf);
655 if (device == NULL)
656 error("%s", ebuf);
657 }
658 #ifdef WIN32
659 if(IsTextUnicode(device,
660 wcslen((short*)device), // Device always ends with a double \0, so this way to determine its
661 // length should be always valid
662 NULL))
663 {
664 fprintf(stderr, "%s: listening on %ws\n", program_name, device);
665 }
666 else
667 {
668 fprintf(stderr, "%s: listening on %s\n", program_name, device);
669 }
670
671 fflush(stderr);
672 #endif /* WIN32 */
673 *ebuf = '\0';
674 pd = pcap_open_live(device, snaplen, !pflag, 1000, ebuf);
675 if (pd == NULL)
676 error("%s", ebuf);
677 else if (*ebuf)
678 warning("%s", ebuf);
679 #ifdef WIN32
680 if(UserBufferSize != 1000000)
681 if(pcap_setbuff(pd, UserBufferSize)==-1){
682 error("%s", pcap_geterr(pd));
683 }
684 #endif /* WIN32 */
685 if (Lflag)
686 show_dlts_and_exit(pd);
687 if (dlt >= 0) {
688 #ifdef HAVE_PCAP_SET_DATALINK
689 if (pcap_set_datalink(pd, dlt) < 0)
690 error("%s", pcap_geterr(pd));
691 #else
692 /*
693 * We don't actually support changing the
694 * data link type, so we only let them
695 * set it to what it already is.
696 */
697 if (dlt != pcap_datalink(pd)) {
698 error("%s is not one of the DLTs supported by this device\n",
699 dlt_name);
700 }
701 #endif
702 (void)fprintf(stderr, "%s: data link type %s\n",
703 program_name, dlt_name);
704 (void)fflush(stderr);
705 }
706 i = pcap_snapshot(pd);
707 if (snaplen < i) {
708 warning("snaplen raised from %d to %d", snaplen, i);
709 snaplen = i;
710 }
711 if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
712 localnet = 0;
713 netmask = 0;
714 warning("%s", ebuf);
715 }
716 /*
717 * Let user own process after socket has been opened.
718 */
719 #ifndef WIN32
720 setuid(getuid());
721 #endif /* WIN32 */
722 }
723 if (infile)
724 cmdbuf = read_infile(infile);
725 else
726 cmdbuf = copy_argv(&argv[optind]);
727
728 if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
729 error("%s", pcap_geterr(pd));
730 if (dflag) {
731 bpf_dump(&fcode, dflag);
732 pcap_close(pd);
733 exit(0);
734 }
735 init_addrtoname(localnet, netmask);
736
737 #ifndef WIN32
738 (void)setsignal(SIGPIPE, cleanup);
739 #endif /* WIN32 */
740 (void)setsignal(SIGTERM, cleanup);
741 (void)setsignal(SIGINT, cleanup);
742 /* Cooperate with nohup(1) */
743 #ifndef WIN32
744 if ((oldhandler = setsignal(SIGHUP, cleanup)) != SIG_DFL)
745 (void)setsignal(SIGHUP, oldhandler);
746 #endif /* WIN32 */
747
748 if (pcap_setfilter(pd, &fcode) < 0)
749 error("%s", pcap_geterr(pd));
750 if (WFileName) {
751 pcap_dumper_t *p = pcap_dump_open(pd, WFileName);
752 if (p == NULL)
753 error("%s", pcap_geterr(pd));
754 if (Cflag != 0) {
755 callback = dump_packet_and_trunc;
756 dumpinfo.WFileName = WFileName;
757 dumpinfo.pd = pd;
758 dumpinfo.p = p;
759 pcap_userdata = (u_char *)&dumpinfo;
760 } else {
761 callback = dump_packet;
762 pcap_userdata = (u_char *)p;
763 }
764 } else {
765 type = pcap_datalink(pd);
766 printinfo.printer = lookup_printer(type);
767 if (printinfo.printer == NULL) {
768 dlt_name = pcap_datalink_val_to_name(type);
769 if (dlt_name != NULL)
770 error("unsupported data link type %s", dlt_name);
771 else
772 error("unsupported data link type %d", type);
773 }
774 callback = print_packet;
775 pcap_userdata = (u_char *)&printinfo;
776 }
777 #ifdef SIGINFO
778 (void)setsignal(SIGINFO, requestinfo);
779 #endif
780 #ifndef WIN32
781 if (RFileName == NULL) {
782 int dlt;
783 const char *dlt_name;
784
785 if (!vflag && !WFileName) {
786 (void)fprintf(stderr,
787 "%s: verbose output suppressed, use -v or -vv for full protocol decode\n",
788 program_name);
789 } else
790 (void)fprintf(stderr, "%s: ", program_name);
791 dlt = pcap_datalink(pd);
792 dlt_name = pcap_datalink_val_to_name(dlt);
793 if (dlt_name == NULL) {
794 (void)fprintf(stderr, "listening on %s, link-type %u, capture size %u bytes\n",
795 device, dlt, snaplen);
796 } else {
797 (void)fprintf(stderr, "listening on %s, link-type %s (%s), capture size %u bytes\n",
798 device, dlt_name,
799 pcap_datalink_val_to_description(dlt), snaplen);
800 }
801 (void)fflush(stderr);
802 }
803 #endif /* WIN32 */
804 status = pcap_loop(pd, cnt, callback, pcap_userdata);
805 if (WFileName == NULL) {
806 /*
807 * We're printing packets. Flush the printed output,
808 * so it doesn't get intermingled with error output.
809 */
810 if (status == -2) {
811 /*
812 * We got interrupted, so perhaps we didn't
813 * manage to finish a line we were printing.
814 * Print an extra newline, just in case.
815 */
816 putchar('\n');
817 }
818 (void)fflush(stdout);
819 }
820 if (status == -1) {
821 /*
822 * Error. Report it.
823 */
824 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
825 program_name, pcap_geterr(pd));
826 }
827 if (RFileName == NULL) {
828 /*
829 * We're doing a live capture. Report the capture
830 * statistics.
831 */
832 info(1);
833 }
834 pcap_close(pd);
835 exit(status == -1 ? 1 : 0);
836 }
837
838 /* make a clean exit on interrupts */
839 static RETSIGTYPE
840 cleanup(int signo _U_)
841 {
842 #ifdef HAVE_PCAP_BREAKLOOP
843 /*
844 * We have "pcap_breakloop()"; use it, so that we do as little
845 * as possible in the signal handler (it's probably not safe
846 * to do anything with standard I/O streams in a signal handler -
847 * the ANSI C standard doesn't say it is).
848 */
849 pcap_breakloop(pd);
850 #else
851 /*
852 * We don't have "pcap_breakloop()"; this isn't safe, but
853 * it's the best we can do. Print the summary if we're
854 * not reading from a savefile - i.e., if we're doing a
855 * live capture - and exit.
856 */
857 if (pd != NULL && pcap_file(pd) == NULL) {
858 /*
859 * We got interrupted, so perhaps we didn't
860 * manage to finish a line we were printing.
861 * Print an extra newline, just in case.
862 */
863 putchar('\n');
864 (void)fflush(stdout);
865 info(1);
866 }
867 exit(0);
868 #endif
869 }
870
871 static void
872 info(register int verbose)
873 {
874 struct pcap_stat stat;
875
876 if (pcap_stats(pd, &stat) < 0) {
877 (void)fprintf(stderr, "pcap_stats: %s\n", pcap_geterr(pd));
878 return;
879 }
880
881 if (!verbose)
882 fprintf(stderr, "%s: ", program_name);
883
884 (void)fprintf(stderr, "%u packets captured", packets_captured);
885 if (!verbose)
886 fputs(", ", stderr);
887 else
888 putc('\n', stderr);
889 (void)fprintf(stderr, "%d packets received by filter", stat.ps_recv);
890 if (!verbose)
891 fputs(", ", stderr);
892 else
893 putc('\n', stderr);
894 (void)fprintf(stderr, "%d packets dropped by kernel\n", stat.ps_drop);
895 infoprint = 0;
896 }
897
898 static void
899 reverse(char *s)
900 {
901 int i, j, c;
902
903 for (i = 0, j = strlen(s) - 1; i < j; i++, j--) {
904 c = s[i];
905 s[i] = s[j];
906 s[j] = c;
907 }
908 }
909
910
911 static void
912 swebitoa(unsigned int n, char *s)
913 {
914 unsigned int i;
915
916 i = 0;
917 do {
918 s[i++] = n % 10 + '0';
919 } while ((n /= 10) > 0);
920
921 s[i] = '\0';
922 reverse(s);
923 }
924
925 static void
926 dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
927 {
928 struct dump_info *dump_info;
929 static uint cnt = 2;
930 char *name;
931
932 ++packets_captured;
933
934 ++infodelay;
935
936 dump_info = (struct dump_info *)user;
937
938 /*
939 * XXX - this won't prevent capture files from getting
940 * larger than Cflag - the last packet written to the
941 * file could put it over Cflag.
942 */
943 if (ftell((FILE *)dump_info->p) > Cflag) {
944 name = (char *) malloc(strlen(dump_info->WFileName) + 4);
945 if (name == NULL)
946 error("dump_packet_and_trunc: malloc");
947 strcpy(name, dump_info->WFileName);
948 swebitoa(cnt, name + strlen(dump_info->WFileName));
949 cnt++;
950 pcap_dump_close(dump_info->p);
951 dump_info->p = pcap_dump_open(dump_info->pd, name);
952 free(name);
953 if (dump_info->p == NULL)
954 error("%s", pcap_geterr(pd));
955 }
956
957 pcap_dump((u_char *)dump_info->p, h, sp);
958 #ifdef HAVE_PCAP_DUMP_FLUSH
959 if (Uflag)
960 pcap_dump_flush(dump_info->p);
961 #endif
962
963 --infodelay;
964 if (infoprint)
965 info(0);
966 }
967
968 static void
969 dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
970 {
971 ++packets_captured;
972
973 ++infodelay;
974
975 pcap_dump(user, h, sp);
976 #ifdef HAVE_PCAP_DUMP_FLUSH
977 if (Uflag)
978 pcap_dump_flush((pcap_dumper_t *)user);
979 #endif
980
981 --infodelay;
982 if (infoprint)
983 info(0);
984 }
985
986 static void
987 print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
988 {
989 struct print_info *print_info;
990 u_int hdrlen;
991
992 ++packets_captured;
993
994 ++infodelay;
995 ts_print(&h->ts);
996
997 print_info = (struct print_info *)user;
998
999 /*
1000 * Some printers want to check that they're not walking off the
1001 * end of the packet.
1002 * Rather than pass it all the way down, we set this global.
1003 */
1004 snapend = sp + h->caplen;
1005
1006 hdrlen = (*print_info->printer)(h, sp);
1007 if (xflag) {
1008 /*
1009 * Print the raw packet data.
1010 */
1011 if (xflag > 1) {
1012 /*
1013 * Include the link-layer header.
1014 */
1015 default_print(sp, h->caplen);
1016 } else {
1017 /*
1018 * Don't include the link-layer header - and if
1019 * we have nothing past the link-layer header,
1020 * print nothing.
1021 */
1022 if (h->caplen > hdrlen)
1023 default_print(sp + hdrlen,
1024 h->caplen - hdrlen);
1025 }
1026 }
1027
1028 putchar('\n');
1029
1030 --infodelay;
1031 if (infoprint)
1032 info(0);
1033 }
1034
1035 #ifdef WIN32
1036 /*
1037 * XXX - there should really be libpcap calls to get the version
1038 * number as a string (the string would be generated from #defines
1039 * at run time, so that it's not generated from string constants
1040 * in the library, as, on many UNIX systems, those constants would
1041 * be statically linked into the application executable image, and
1042 * would thus reflect the version of libpcap on the system on
1043 * which the application was *linked*, not the system on which it's
1044 * *running*.
1045 *
1046 * That routine should be documented, unlike the "version[]"
1047 * string, so that UNIX vendors providing their own libpcaps
1048 * don't omit it (as a couple of vendors have...).
1049 *
1050 * Packet.dll should perhaps also export a routine to return the
1051 * version number of the Packet.dll code, to supply the
1052 * "Wpcap_version" information on Windows.
1053 */
1054 char WDversion[]="current-cvs.tcpdump.org";
1055 char version[]="current-cvs.tcpdump.org";
1056 char pcap_version[]="current-cvs.tcpdump.org";
1057 char Wpcap_version[]="3.0 alpha";
1058 #endif
1059
1060 /*
1061 * By default, print the specified data out in hex.
1062 */
1063 void
1064 default_print(register const u_char *bp, register u_int length)
1065 {
1066 ascii_print("\n\t", bp, length); /* pass on lf and identation string */
1067 }
1068
1069 #ifdef SIGINFO
1070 RETSIGTYPE requestinfo(int signo _U_)
1071 {
1072 if (infodelay)
1073 ++infoprint;
1074 else
1075 info(0);
1076 }
1077 #endif
1078
1079 static void
1080 usage(void)
1081 {
1082 extern char version[];
1083 #ifndef HAVE_PCAP_LIB_VERSION
1084 #if defined(WIN32) || defined(HAVE_PCAP_VERSION)
1085 extern char pcap_version[];
1086 #else /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
1087 static char pcap_version[] = "unknown";
1088 #endif /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
1089 #endif /* HAVE_PCAP_LIB_VERSION */
1090
1091 #ifdef HAVE_PCAP_LIB_VERSION
1092 (void)fprintf(stderr, "%s version %s\n", program_name, version);
1093 (void)fprintf(stderr, "%s\n", pcap_lib_version());
1094 #else /* HAVE_PCAP_LIB_VERSION */
1095 #ifdef WIN32
1096 (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
1097 (void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version);
1098 #else /* WIN32 */
1099 (void)fprintf(stderr, "%s version %s\n", program_name, version);
1100 (void)fprintf(stderr, "libpcap version %s\n", pcap_version);
1101 #endif /* WIN32 */
1102 #endif /* HAVE_PCAP_LIB_VERSION */
1103 (void)fprintf(stderr,
1104 "Usage: %s [-aAd" D_FLAG "eflLnNOpqRStu" U_FLAG "vxX]" B_FLAG_USAGE " [-c count] [ -C file_size ]\n", program_name);
1105 (void)fprintf(stderr,
1106 "\t\t[ -E algo:secret ] [ -F file ] [ -i interface ] [ -r file ]\n");
1107 (void)fprintf(stderr,
1108 "\t\t[ -s snaplen ] [ -T type ] [ -w file ] [ -y datalinktype ]\n");
1109 (void)fprintf(stderr,
1110 "\t\t[ expression ]\n");
1111 exit(1);
1112 }
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