xref: /dragonfly/contrib/tcpdump/tcpdump.c (revision 9ddb8543)
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 1.271.2.11 2008-09-25 21:50:04 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 #ifdef HAVE_SMI_H
60 #include <smi.h>
61 #endif
62 
63 #include <pcap.h>
64 #include <signal.h>
65 #include <stdio.h>
66 #include <stdlib.h>
67 #include <string.h>
68 #include <limits.h>
69 #ifndef WIN32
70 #include <sys/wait.h>
71 #include <sys/resource.h>
72 #include <pwd.h>
73 #include <grp.h>
74 #include <errno.h>
75 #endif /* WIN32 */
76 
77 
78 #include "netdissect.h"
79 #include "interface.h"
80 #include "addrtoname.h"
81 #include "machdep.h"
82 #include "setsignal.h"
83 #include "gmt2local.h"
84 #include "pcap-missing.h"
85 
86 #ifndef NAME_MAX
87 #define NAME_MAX 255
88 #endif
89 
90 netdissect_options Gndo;
91 netdissect_options *gndo = &Gndo;
92 
93 int dflag;			/* print filter code */
94 int Lflag;			/* list available data link types and exit */
95 char *zflag = NULL;		/* compress each savefile using a specified command (like gzip or bzip2) */
96 
97 static int infodelay;
98 static int infoprint;
99 
100 char *program_name;
101 
102 int32_t thiszone;		/* seconds offset from gmt to local time */
103 
104 /* Forwards */
105 static RETSIGTYPE cleanup(int);
106 static RETSIGTYPE child_cleanup(int);
107 static void usage(void) __attribute__((noreturn));
108 static void show_dlts_and_exit(pcap_t *pd) __attribute__((noreturn));
109 
110 static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
111 static void ndo_default_print(netdissect_options *, const u_char *, u_int);
112 static void dump_packet_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *);
113 static void dump_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
114 static void droproot(const char *, const char *);
115 static void ndo_error(netdissect_options *ndo, const char *fmt, ...);
116 static void ndo_warning(netdissect_options *ndo, const char *fmt, ...);
117 
118 #ifdef SIGINFO
119 RETSIGTYPE requestinfo(int);
120 #endif
121 
122 #if defined(USE_WIN32_MM_TIMER)
123   #include <MMsystem.h>
124   static UINT timer_id;
125   static void CALLBACK verbose_stats_dump(UINT, UINT, DWORD_PTR, DWORD_PTR, DWORD_PTR);
126 #elif defined(HAVE_ALARM)
127   static void verbose_stats_dump(int sig);
128 #endif
129 
130 static void info(int);
131 static u_int packets_captured;
132 
133 typedef u_int (*if_printer)(const struct pcap_pkthdr *, const u_char *);
134 
135 struct printer {
136 	if_printer f;
137 	int type;
138 };
139 
140 static struct printer printers[] = {
141 	{ arcnet_if_print,	DLT_ARCNET },
142 #ifdef DLT_ARCNET_LINUX
143 	{ arcnet_linux_if_print, DLT_ARCNET_LINUX },
144 #endif
145 	{ ether_if_print,	DLT_EN10MB },
146 	{ token_if_print,	DLT_IEEE802 },
147 #ifdef DLT_LANE8023
148 	{ lane_if_print,        DLT_LANE8023 },
149 #endif
150 #ifdef DLT_CIP
151 	{ cip_if_print,         DLT_CIP },
152 #endif
153 #ifdef DLT_ATM_CLIP
154 	{ cip_if_print,         DLT_ATM_CLIP },
155 #endif
156 	{ sl_if_print,		DLT_SLIP },
157 #ifdef DLT_SLIP_BSDOS
158 	{ sl_bsdos_if_print,	DLT_SLIP_BSDOS },
159 #endif
160 	{ ppp_if_print,		DLT_PPP },
161 #ifdef DLT_PPP_WITHDIRECTION
162 	{ ppp_if_print,		DLT_PPP_WITHDIRECTION },
163 #endif
164 #ifdef DLT_PPP_BSDOS
165 	{ ppp_bsdos_if_print,	DLT_PPP_BSDOS },
166 #endif
167 	{ fddi_if_print,	DLT_FDDI },
168 	{ null_if_print,	DLT_NULL },
169 #ifdef DLT_LOOP
170 	{ null_if_print,	DLT_LOOP },
171 #endif
172 	{ raw_if_print,		DLT_RAW },
173 	{ atm_if_print,		DLT_ATM_RFC1483 },
174 #ifdef DLT_C_HDLC
175 	{ chdlc_if_print,	DLT_C_HDLC },
176 #endif
177 #ifdef DLT_HDLC
178 	{ chdlc_if_print,	DLT_HDLC },
179 #endif
180 #ifdef DLT_PPP_SERIAL
181 	{ ppp_hdlc_if_print,    DLT_PPP_SERIAL },
182 #endif
183 #ifdef DLT_PPP_ETHER
184 	{ pppoe_if_print,	DLT_PPP_ETHER },
185 #endif
186 #ifdef DLT_LINUX_SLL
187 	{ sll_if_print,		DLT_LINUX_SLL },
188 #endif
189 #ifdef DLT_IEEE802_11
190 	{ ieee802_11_if_print,	DLT_IEEE802_11},
191 #endif
192 #ifdef DLT_LTALK
193 	{ ltalk_if_print,	DLT_LTALK },
194 #endif
195 #if defined(DLT_PFLOG) && defined(HAVE_NET_PFVAR_H)
196 	{ pflog_if_print, 	DLT_PFLOG },
197 #endif
198 #ifdef DLT_FR
199 	{ fr_if_print,		DLT_FR },
200 #endif
201 #ifdef DLT_FRELAY
202 	{ fr_if_print,		DLT_FRELAY },
203 #endif
204 #ifdef DLT_SUNATM
205 	{ sunatm_if_print,	DLT_SUNATM },
206 #endif
207 #ifdef DLT_IP_OVER_FC
208 	{ ipfc_if_print,	DLT_IP_OVER_FC },
209 #endif
210 #ifdef DLT_PRISM_HEADER
211 	{ prism_if_print,	DLT_PRISM_HEADER },
212 #endif
213 #ifdef DLT_IEEE802_11_RADIO
214 	{ ieee802_11_radio_if_print,	DLT_IEEE802_11_RADIO },
215 #endif
216 #ifdef DLT_ENC
217 	{ enc_if_print, 	DLT_ENC },
218 #endif
219 #ifdef DLT_SYMANTEC_FIREWALL
220 	{ symantec_if_print, 	DLT_SYMANTEC_FIREWALL },
221 #endif
222 #ifdef DLT_APPLE_IP_OVER_IEEE1394
223 	{ ap1394_if_print,	DLT_APPLE_IP_OVER_IEEE1394 },
224 #endif
225 #ifdef DLT_IEEE802_11_RADIO_AVS
226 	{ ieee802_11_radio_avs_if_print,	DLT_IEEE802_11_RADIO_AVS },
227 #endif
228 #ifdef DLT_JUNIPER_ATM1
229 	{ juniper_atm1_print,	DLT_JUNIPER_ATM1 },
230 #endif
231 #ifdef DLT_JUNIPER_ATM2
232 	{ juniper_atm2_print,	DLT_JUNIPER_ATM2 },
233 #endif
234 #ifdef DLT_JUNIPER_MFR
235 	{ juniper_mfr_print,	DLT_JUNIPER_MFR },
236 #endif
237 #ifdef DLT_JUNIPER_MLFR
238 	{ juniper_mlfr_print,	DLT_JUNIPER_MLFR },
239 #endif
240 #ifdef DLT_JUNIPER_MLPPP
241 	{ juniper_mlppp_print,	DLT_JUNIPER_MLPPP },
242 #endif
243 #ifdef DLT_JUNIPER_PPPOE
244 	{ juniper_pppoe_print,	DLT_JUNIPER_PPPOE },
245 #endif
246 #ifdef DLT_JUNIPER_PPPOE_ATM
247 	{ juniper_pppoe_atm_print, DLT_JUNIPER_PPPOE_ATM },
248 #endif
249 #ifdef DLT_JUNIPER_GGSN
250 	{ juniper_ggsn_print,	DLT_JUNIPER_GGSN },
251 #endif
252 #ifdef DLT_JUNIPER_ES
253 	{ juniper_es_print,	DLT_JUNIPER_ES },
254 #endif
255 #ifdef DLT_JUNIPER_MONITOR
256 	{ juniper_monitor_print, DLT_JUNIPER_MONITOR },
257 #endif
258 #ifdef DLT_JUNIPER_SERVICES
259 	{ juniper_services_print, DLT_JUNIPER_SERVICES },
260 #endif
261 #ifdef DLT_JUNIPER_ETHER
262 	{ juniper_ether_print, DLT_JUNIPER_ETHER },
263 #endif
264 #ifdef DLT_JUNIPER_PPP
265 	{ juniper_ppp_print, DLT_JUNIPER_PPP },
266 #endif
267 #ifdef DLT_JUNIPER_FRELAY
268 	{ juniper_frelay_print, DLT_JUNIPER_FRELAY },
269 #endif
270 #ifdef DLT_JUNIPER_CHDLC
271 	{ juniper_chdlc_print, DLT_JUNIPER_CHDLC },
272 #endif
273 #ifdef DLT_MFR
274 	{ mfr_if_print, DLT_MFR },
275 #endif
276 #if defined(DLT_BLUETOOTH_HCI_H4_WITH_PHDR) && defined(HAVE_PCAP_BLUETOOTH_H)
277 	{ bt_if_print, DLT_BLUETOOTH_HCI_H4_WITH_PHDR},
278 #endif
279 	{ NULL,			0 },
280 };
281 
282 static if_printer
283 lookup_printer(int type)
284 {
285 	struct printer *p;
286 
287 	for (p = printers; p->f; ++p)
288 		if (type == p->type)
289 			return p->f;
290 
291 	return NULL;
292 	/* NOTREACHED */
293 }
294 
295 static pcap_t *pd;
296 
297 extern int optind;
298 extern int opterr;
299 extern char *optarg;
300 
301 struct print_info {
302 	if_printer printer;
303 };
304 
305 struct dump_info {
306 	char	*WFileName;
307 	char	*CurrentFileName;
308 	pcap_t	*pd;
309 	pcap_dumper_t *p;
310 };
311 
312 static void
313 show_dlts_and_exit(pcap_t *pd)
314 {
315 	int n_dlts;
316 	int *dlts = 0;
317 	const char *dlt_name;
318 
319 	n_dlts = pcap_list_datalinks(pd, &dlts);
320 	if (n_dlts < 0)
321 		error("%s", pcap_geterr(pd));
322 	else if (n_dlts == 0 || !dlts)
323 		error("No data link types.");
324 
325 	(void) fprintf(stderr, "Data link types (use option -y to set):\n");
326 
327 	while (--n_dlts >= 0) {
328 		dlt_name = pcap_datalink_val_to_name(dlts[n_dlts]);
329 		if (dlt_name != NULL) {
330 			(void) fprintf(stderr, "  %s (%s)", dlt_name,
331 			    pcap_datalink_val_to_description(dlts[n_dlts]));
332 
333 			/*
334 			 * OK, does tcpdump handle that type?
335 			 */
336 			if (lookup_printer(dlts[n_dlts]) == NULL)
337 				(void) fprintf(stderr, " (printing not supported)");
338 			putchar('\n');
339 		} else {
340 			(void) fprintf(stderr, "  DLT %d (printing not supported)\n",
341 			    dlts[n_dlts]);
342 		}
343 	}
344 	free(dlts);
345 	exit(0);
346 }
347 
348 /*
349  * Set up flags that might or might not be supported depending on the
350  * version of libpcap we're using.
351  */
352 #if defined(HAVE_PCAP_CREATE) || defined(WIN32)
353 #define B_FLAG		"B:"
354 #define B_FLAG_USAGE	" [ -B size ]"
355 #else /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
356 #define B_FLAG
357 #define B_FLAG_USAGE
358 #endif /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
359 
360 #ifdef HAVE_PCAP_CREATE
361 #define I_FLAG		"I"
362 #else /* HAVE_PCAP_CREATE */
363 #define I_FLAG
364 #endif /* HAVE_PCAP_CREATE */
365 
366 #ifdef HAVE_PCAP_FINDALLDEVS
367 #ifndef HAVE_PCAP_IF_T
368 #undef HAVE_PCAP_FINDALLDEVS
369 #endif
370 #endif
371 
372 #ifdef HAVE_PCAP_FINDALLDEVS
373 #define D_FLAG	"D"
374 #else
375 #define D_FLAG
376 #endif
377 
378 #ifdef HAVE_PCAP_DUMP_FLUSH
379 #define U_FLAG	"U"
380 #else
381 #define U_FLAG
382 #endif
383 
384 #ifndef WIN32
385 /* Drop root privileges and chroot if necessary */
386 static void
387 droproot(const char *username, const char *chroot_dir)
388 {
389 	struct passwd *pw = NULL;
390 
391 	if (chroot_dir && !username) {
392 		fprintf(stderr, "tcpdump: Chroot without dropping root is insecure\n");
393 		exit(1);
394 	}
395 
396 	pw = getpwnam(username);
397 	if (pw) {
398 		if (chroot_dir) {
399 			if (chroot(chroot_dir) != 0 || chdir ("/") != 0) {
400 				fprintf(stderr, "tcpdump: Couldn't chroot/chdir to '%.64s': %s\n",
401 				    chroot_dir, pcap_strerror(errno));
402 				exit(1);
403 			}
404 		}
405 		if (initgroups(pw->pw_name, pw->pw_gid) != 0 ||
406 		    setgid(pw->pw_gid) != 0 || setuid(pw->pw_uid) != 0) {
407 			fprintf(stderr, "tcpdump: Couldn't change to '%.32s' uid=%lu gid=%lu: %s\n",
408 			    username,
409 			    (unsigned long)pw->pw_uid,
410 			    (unsigned long)pw->pw_gid,
411 			    pcap_strerror(errno));
412 			exit(1);
413 		}
414 	}
415 	else {
416 		fprintf(stderr, "tcpdump: Couldn't find user '%.32s'\n",
417 		    username);
418 		exit(1);
419 	}
420 }
421 #endif /* WIN32 */
422 
423 static int
424 getWflagChars(int x)
425 {
426 	int c = 0;
427 
428 	x -= 1;
429 	while (x > 0) {
430 		c += 1;
431 		x /= 10;
432 	}
433 
434 	return c;
435 }
436 
437 
438 static void
439 MakeFilename(char *buffer, char *orig_name, int cnt, int max_chars)
440 {
441         char *filename = malloc(NAME_MAX + 1);
442 
443         /* Process with strftime if Gflag is set. */
444         if (Gflag != 0) {
445           struct tm *local_tm;
446 
447           /* Convert Gflag_time to a usable format */
448           if ((local_tm = localtime(&Gflag_time)) == NULL) {
449                   error("MakeTimedFilename: localtime");
450           }
451 
452           /* There's no good way to detect an error in strftime since a return
453            * value of 0 isn't necessarily failure.
454            */
455           strftime(filename, NAME_MAX, orig_name, local_tm);
456         } else {
457           strncpy(filename, orig_name, NAME_MAX);
458         }
459 
460 	if (cnt == 0 && max_chars == 0)
461 		strncpy(buffer, filename, NAME_MAX + 1);
462 	else
463 		if (snprintf(buffer, NAME_MAX + 1, "%s%0*d", filename, max_chars, cnt) > NAME_MAX)
464                   /* Report an error if the filename is too large */
465                   error("too many output files or filename is too long (> %d)", NAME_MAX);
466         free(filename);
467 }
468 
469 static int tcpdump_printf(netdissect_options *ndo _U_,
470 			  const char *fmt, ...)
471 {
472 
473   va_list args;
474   int ret;
475 
476   va_start(args, fmt);
477   ret=vfprintf(stdout, fmt, args);
478   va_end(args);
479 
480   return ret;
481 }
482 
483 int
484 main(int argc, char **argv)
485 {
486 	register int cnt, op, i;
487 	bpf_u_int32 localnet, netmask;
488 	register char *cp, *infile, *cmdbuf, *device, *RFileName, *WFileName;
489 	pcap_handler callback;
490 	int type;
491 	struct bpf_program fcode;
492 #ifndef WIN32
493 	RETSIGTYPE (*oldhandler)(int);
494 #endif
495 	struct print_info printinfo;
496 	struct dump_info dumpinfo;
497 	u_char *pcap_userdata;
498 	char ebuf[PCAP_ERRBUF_SIZE];
499 	char *username = NULL;
500 	char *chroot_dir = NULL;
501 #ifdef HAVE_PCAP_FINDALLDEVS
502 	pcap_if_t *devpointer;
503 	int devnum;
504 #endif
505 	int status;
506 #ifdef WIN32
507 	if(wsockinit() != 0) return 1;
508 #endif /* WIN32 */
509 
510         gndo->ndo_Oflag=1;
511 	gndo->ndo_Rflag=1;
512 	gndo->ndo_dlt=-1;
513 	gndo->ndo_default_print=ndo_default_print;
514 	gndo->ndo_printf=tcpdump_printf;
515 	gndo->ndo_error=ndo_error;
516 	gndo->ndo_warning=ndo_warning;
517 	gndo->ndo_snaplen = DEFAULT_SNAPLEN;
518 
519 	cnt = -1;
520 	device = NULL;
521 	infile = NULL;
522 	RFileName = NULL;
523 	WFileName = NULL;
524 	if ((cp = strrchr(argv[0], '/')) != NULL)
525 		program_name = cp + 1;
526 	else
527 		program_name = argv[0];
528 
529 	if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
530 		error("%s", ebuf);
531 
532 #ifdef LIBSMI
533 	smiInit("tcpdump");
534 #endif
535 
536 	opterr = 0;
537 	while (
538 	    (op = getopt(argc, argv, "aA" B_FLAG "c:C:d" D_FLAG "eE:fF:G:i:" I_FLAG "KlLm:M:nNOpqr:Rs:StT:u" U_FLAG "vw:W:xXy:Yz:Z:")) != -1)
539 		switch (op) {
540 
541 		case 'a':
542 			/* compatibility for old -a */
543 			break;
544 
545 		case 'A':
546 			++Aflag;
547 			break;
548 
549 #if defined(HAVE_PCAP_CREATE) || defined(WIN32)
550 		case 'B':
551 			Bflag = atoi(optarg)*1024;
552 			if (Bflag <= 0)
553 				error("invalid packet buffer size %s", optarg);
554 			break;
555 #endif /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
556 
557 		case 'c':
558 			cnt = atoi(optarg);
559 			if (cnt <= 0)
560 				error("invalid packet count %s", optarg);
561 			break;
562 
563 		case 'C':
564 			Cflag = atoi(optarg) * 1000000;
565 			if (Cflag < 0)
566 				error("invalid file size %s", optarg);
567 			break;
568 
569 		case 'd':
570 			++dflag;
571 			break;
572 
573 #ifdef HAVE_PCAP_FINDALLDEVS
574 		case 'D':
575 			if (pcap_findalldevs(&devpointer, ebuf) < 0)
576 				error("%s", ebuf);
577 			else {
578 				for (i = 0; devpointer != 0; i++) {
579 					printf("%d.%s", i+1, devpointer->name);
580 					if (devpointer->description != NULL)
581 						printf(" (%s)", devpointer->description);
582 					printf("\n");
583 					devpointer = devpointer->next;
584 				}
585 			}
586 			return 0;
587 #endif /* HAVE_PCAP_FINDALLDEVS */
588 
589 		case 'L':
590 			Lflag++;
591 			break;
592 
593 		case 'e':
594 			++eflag;
595 			break;
596 
597 		case 'E':
598 #ifndef HAVE_LIBCRYPTO
599 			warning("crypto code not compiled in");
600 #endif
601 			gndo->ndo_espsecret = optarg;
602 			break;
603 
604 		case 'f':
605 			++fflag;
606 			break;
607 
608 		case 'F':
609 			infile = optarg;
610 			break;
611 
612 		case 'G':
613 			Gflag = atoi(optarg);
614 			if (Gflag < 0)
615 				error("invalid number of seconds %s", optarg);
616 
617                         /* We will create one file initially. */
618                         Gflag_count = 0;
619 
620 			/* Grab the current time for rotation use. */
621 			if ((Gflag_time = time(NULL)) == (time_t)-1) {
622 				error("main: can't get current time: %s",
623 				    pcap_strerror(errno));
624 			}
625 			break;
626 
627 		case 'i':
628 			if (optarg[0] == '0' && optarg[1] == 0)
629 				error("Invalid adapter index");
630 
631 #ifdef HAVE_PCAP_FINDALLDEVS
632 			/*
633 			 * If the argument is a number, treat it as
634 			 * an index into the list of adapters, as
635 			 * printed by "tcpdump -D".
636 			 *
637 			 * This should be OK on UNIX systems, as interfaces
638 			 * shouldn't have names that begin with digits.
639 			 * It can be useful on Windows, where more than
640 			 * one interface can have the same name.
641 			 */
642 			if ((devnum = atoi(optarg)) != 0) {
643 				if (devnum < 0)
644 					error("Invalid adapter index");
645 
646 				if (pcap_findalldevs(&devpointer, ebuf) < 0)
647 					error("%s", ebuf);
648 				else {
649 					for (i = 0; i < devnum-1; i++){
650 						devpointer = devpointer->next;
651 						if (devpointer == NULL)
652 							error("Invalid adapter index");
653 					}
654 				}
655 				device = devpointer->name;
656 				break;
657 			}
658 #endif /* HAVE_PCAP_FINDALLDEVS */
659 			device = optarg;
660 			break;
661 
662 #ifdef HAVE_PCAP_CREATE
663 		case 'I':
664 			++Iflag;
665 			break;
666 #endif /* HAVE_PCAP_CREATE */
667 
668 		case 'l':
669 #ifdef WIN32
670 			/*
671 			 * _IOLBF is the same as _IOFBF in Microsoft's C
672 			 * libraries; the only alternative they offer
673 			 * is _IONBF.
674 			 *
675 			 * XXX - this should really be checking for MSVC++,
676 			 * not WIN32, if, for example, MinGW has its own
677 			 * C library that is more UNIX-compatible.
678 			 */
679 			setvbuf(stdout, NULL, _IONBF, 0);
680 #else /* WIN32 */
681 #ifdef HAVE_SETLINEBUF
682 			setlinebuf(stdout);
683 #else
684 			setvbuf(stdout, NULL, _IOLBF, 0);
685 #endif
686 #endif /* WIN32 */
687 			break;
688 
689 		case 'K':
690 			++Kflag;
691 			break;
692 
693 		case 'm':
694 #ifdef LIBSMI
695 			if (smiLoadModule(optarg) == 0) {
696 				error("could not load MIB module %s", optarg);
697 			}
698 			sflag = 1;
699 #else
700 			(void)fprintf(stderr, "%s: ignoring option `-m %s' ",
701 				      program_name, optarg);
702 			(void)fprintf(stderr, "(no libsmi support)\n");
703 #endif
704 			break;
705 
706 		case 'M':
707 			/* TCP-MD5 shared secret */
708 #ifndef HAVE_LIBCRYPTO
709 			warning("crypto code not compiled in");
710 #endif
711 			tcpmd5secret = optarg;
712 			break;
713 
714 		case 'n':
715 			++nflag;
716 			break;
717 
718 		case 'N':
719 			++Nflag;
720 			break;
721 
722 		case 'O':
723 			Oflag = 0;
724 			break;
725 
726 		case 'p':
727 			++pflag;
728 			break;
729 
730 		case 'q':
731 			++qflag;
732 			++suppress_default_print;
733 			break;
734 
735 		case 'r':
736 			RFileName = optarg;
737 			break;
738 
739 		case 'R':
740 			Rflag = 0;
741 			break;
742 
743 		case 's': {
744 			char *end;
745 
746 			snaplen = strtol(optarg, &end, 0);
747 			if (optarg == end || *end != '\0'
748 			    || snaplen < 0 || snaplen > 65535)
749 				error("invalid snaplen %s", optarg);
750 			else if (snaplen == 0)
751 				snaplen = 65535;
752 			break;
753 		}
754 
755 		case 'S':
756 			++Sflag;
757 			break;
758 
759 		case 't':
760 			++tflag;
761 			break;
762 
763 		case 'T':
764 			if (strcasecmp(optarg, "vat") == 0)
765 				packettype = PT_VAT;
766 			else if (strcasecmp(optarg, "wb") == 0)
767 				packettype = PT_WB;
768 			else if (strcasecmp(optarg, "rpc") == 0)
769 				packettype = PT_RPC;
770 			else if (strcasecmp(optarg, "rtp") == 0)
771 				packettype = PT_RTP;
772 			else if (strcasecmp(optarg, "rtcp") == 0)
773 				packettype = PT_RTCP;
774 			else if (strcasecmp(optarg, "snmp") == 0)
775 				packettype = PT_SNMP;
776 			else if (strcasecmp(optarg, "cnfp") == 0)
777 				packettype = PT_CNFP;
778 			else if (strcasecmp(optarg, "tftp") == 0)
779 				packettype = PT_TFTP;
780 			else if (strcasecmp(optarg, "aodv") == 0)
781 				packettype = PT_AODV;
782 			else
783 				error("unknown packet type `%s'", optarg);
784 			break;
785 
786 		case 'u':
787 			++uflag;
788 			break;
789 
790 #ifdef HAVE_PCAP_DUMP_FLUSH
791 		case 'U':
792 			++Uflag;
793 			break;
794 #endif
795 
796 		case 'v':
797 			++vflag;
798 			break;
799 
800 		case 'w':
801 			WFileName = optarg;
802 			break;
803 
804 		case 'W':
805 			Wflag = atoi(optarg);
806 			if (Wflag < 0)
807 				error("invalid number of output files %s", optarg);
808 			WflagChars = getWflagChars(Wflag);
809 			break;
810 
811 		case 'x':
812 			++xflag;
813 			++suppress_default_print;
814 			break;
815 
816 		case 'X':
817 			++Xflag;
818 			++suppress_default_print;
819 			break;
820 
821 		case 'y':
822 			gndo->ndo_dltname = optarg;
823 			gndo->ndo_dlt =
824 			  pcap_datalink_name_to_val(gndo->ndo_dltname);
825 			if (gndo->ndo_dlt < 0)
826 				error("invalid data link type %s", gndo->ndo_dltname);
827 			break;
828 
829 #if defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG)
830 		case 'Y':
831 			{
832 			/* Undocumented flag */
833 #ifdef HAVE_PCAP_DEBUG
834 			extern int pcap_debug;
835 			pcap_debug = 1;
836 #else
837 			extern int yydebug;
838 			yydebug = 1;
839 #endif
840 			}
841 			break;
842 #endif
843 		case 'z':
844 			if (optarg) {
845 				zflag = strdup(optarg);
846 			} else {
847 				usage();
848 				/* NOTREACHED */
849 			}
850 			break;
851 
852 		case 'Z':
853 			if (optarg) {
854 				username = strdup(optarg);
855 			}
856 			else {
857 				usage();
858 				/* NOTREACHED */
859 			}
860 			break;
861 
862 		default:
863 			usage();
864 			/* NOTREACHED */
865 		}
866 
867 	switch (tflag) {
868 
869 	case 0: /* Default */
870 	case 4: /* Default + Date*/
871 		thiszone = gmt2local(0);
872 		break;
873 
874 	case 1: /* No time stamp */
875 	case 2: /* Unix timeval style */
876 	case 3: /* Microseconds since previous packet */
877         case 5: /* Microseconds since first packet */
878 		break;
879 
880 	default: /* Not supported */
881 		error("only -t, -tt, -ttt, -tttt and -ttttt are supported");
882 		break;
883 	}
884 
885 #ifdef WITH_CHROOT
886 	/* if run as root, prepare for chrooting */
887 	if (getuid() == 0 || geteuid() == 0) {
888 		/* future extensibility for cmd-line arguments */
889 		if (!chroot_dir)
890 			chroot_dir = WITH_CHROOT;
891 	}
892 #endif
893 
894 #ifdef WITH_USER
895 	/* if run as root, prepare for dropping root privileges */
896 	if (getuid() == 0 || geteuid() == 0) {
897 		/* Run with '-Z root' to restore old behaviour */
898 		if (!username)
899 			username = WITH_USER;
900 	}
901 #endif
902 
903 	if (RFileName != NULL) {
904 		int dlt;
905 		const char *dlt_name;
906 
907 #ifndef WIN32
908 		/*
909 		 * We don't need network access, so relinquish any set-UID
910 		 * or set-GID privileges we have (if any).
911 		 *
912 		 * We do *not* want set-UID privileges when opening a
913 		 * trace file, as that might let the user read other
914 		 * people's trace files (especially if we're set-UID
915 		 * root).
916 		 */
917 		if (setgid(getgid()) != 0 || setuid(getuid()) != 0 )
918 			fprintf(stderr, "Warning: setgid/setuid failed !\n");
919 #endif /* WIN32 */
920 		pd = pcap_open_offline(RFileName, ebuf);
921 		if (pd == NULL)
922 			error("%s", ebuf);
923 		dlt = pcap_datalink(pd);
924 		dlt_name = pcap_datalink_val_to_name(dlt);
925 		if (dlt_name == NULL) {
926 			fprintf(stderr, "reading from file %s, link-type %u\n",
927 			    RFileName, dlt);
928 		} else {
929 			fprintf(stderr,
930 			    "reading from file %s, link-type %s (%s)\n",
931 			    RFileName, dlt_name,
932 			    pcap_datalink_val_to_description(dlt));
933 		}
934 		localnet = 0;
935 		netmask = 0;
936 		if (fflag != 0)
937 			error("-f and -r options are incompatible");
938 	} else {
939 		if (device == NULL) {
940 			device = pcap_lookupdev(ebuf);
941 			if (device == NULL)
942 				error("%s", ebuf);
943 		}
944 #ifdef WIN32
945 		if(strlen(device) == 1)	//we assume that an ASCII string is always longer than 1 char
946 		{						//a Unicode string has a \0 as second byte (so strlen() is 1)
947 			fprintf(stderr, "%s: listening on %ws\n", program_name, device);
948 		}
949 		else
950 		{
951 			fprintf(stderr, "%s: listening on %s\n", program_name, device);
952 		}
953 
954 		fflush(stderr);
955 #endif /* WIN32 */
956 #ifdef HAVE_PCAP_CREATE
957 		pd = pcap_create(device, ebuf);
958 		if (pd == NULL)
959 			error("%s", ebuf);
960 		status = pcap_set_snaplen(pd, snaplen);
961 		if (status != 0)
962 			error("%s: pcap_set_snaplen failed: %s",
963 			    device, pcap_statustostr(status));
964 		status = pcap_set_promisc(pd, !pflag);
965 		if (status != 0)
966 			error("%s: pcap_set_promisc failed: %s",
967 			    device, pcap_statustostr(status));
968 		if (Iflag) {
969 			status = pcap_set_rfmon(pd, 1);
970 			if (status != 0)
971 				error("%s: pcap_set_rfmon failed: %s",
972 				    device, pcap_statustostr(status));
973 		}
974 		status = pcap_set_timeout(pd, 1000);
975 		if (status != 0)
976 			error("%s: pcap_set_timeout failed: %s",
977 			    device, pcap_statustostr(status));
978 		if (Bflag != 0) {
979 			status = pcap_set_buffer_size(pd, Bflag);
980 			if (status != 0)
981 				error("%s: pcap_set_buffer_size failed: %s",
982 				    device, pcap_statustostr(status));
983 		}
984 		status = pcap_activate(pd);
985 		if (status < 0) {
986 			/*
987 			 * pcap_activate() failed.
988 			 */
989 			cp = pcap_geterr(pd);
990 			if (status == PCAP_ERROR)
991 				error("%s", cp);
992 			else if ((status == PCAP_ERROR_NO_SUCH_DEVICE ||
993 			          status == PCAP_ERROR_PERM_DENIED) &&
994 			         *cp != '\0')
995 				error("%s: %s\n(%s)", device,
996 				    pcap_statustostr(status), cp);
997 			else
998 				error("%s: %s", device,
999 				    pcap_statustostr(status));
1000 		} else if (status > 0) {
1001 			/*
1002 			 * pcap_activate() succeeded, but it's warning us
1003 			 * of a problem it had.
1004 			 */
1005 			cp = pcap_geterr(pd);
1006 			if (status == PCAP_WARNING)
1007 				warning("%s", cp);
1008 			else if (status == PCAP_WARNING_PROMISC_NOTSUP &&
1009 			         *cp != '\0')
1010 				warning("%s: %s\n(%s)", device,
1011 				    pcap_statustostr(status), cp);
1012 			else
1013 				warning("%s: %s", device,
1014 				    pcap_statustostr(status));
1015 		}
1016 #else
1017 		*ebuf = '\0';
1018 		pd = pcap_open_live(device, snaplen, !pflag, 1000, ebuf);
1019 		if (pd == NULL)
1020 			error("%s", ebuf);
1021 		else if (*ebuf)
1022 			warning("%s", ebuf);
1023 #endif /* HAVE_PCAP_CREATE */
1024 		/*
1025 		 * Let user own process after socket has been opened.
1026 		 */
1027 #ifndef WIN32
1028 		if (setgid(getgid()) != 0 || setuid(getuid()) != 0)
1029 			fprintf(stderr, "Warning: setgid/setuid failed !\n");
1030 #endif /* WIN32 */
1031 #if !defined(HAVE_PCAP_CREATE) && defined(WIN32)
1032 		if(Bflag != 0)
1033 			if(pcap_setbuff(pd, Bflag)==-1){
1034 				error("%s", pcap_geterr(pd));
1035 			}
1036 #endif /* !defined(HAVE_PCAP_CREATE) && defined(WIN32) */
1037 		if (Lflag)
1038 			show_dlts_and_exit(pd);
1039 		if (gndo->ndo_dlt >= 0) {
1040 #ifdef HAVE_PCAP_SET_DATALINK
1041 			if (pcap_set_datalink(pd, gndo->ndo_dlt) < 0)
1042 				error("%s", pcap_geterr(pd));
1043 #else
1044 			/*
1045 			 * We don't actually support changing the
1046 			 * data link type, so we only let them
1047 			 * set it to what it already is.
1048 			 */
1049 			if (gndo->ndo_dlt != pcap_datalink(pd)) {
1050 				error("%s is not one of the DLTs supported by this device\n",
1051 				      gndo->ndo_dltname);
1052 			}
1053 #endif
1054 			(void)fprintf(stderr, "%s: data link type %s\n",
1055 				      program_name, gndo->ndo_dltname);
1056 			(void)fflush(stderr);
1057 		}
1058 		i = pcap_snapshot(pd);
1059 		if (snaplen < i) {
1060 			warning("snaplen raised from %d to %d", snaplen, i);
1061 			snaplen = i;
1062 		}
1063 		if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
1064 			localnet = 0;
1065 			netmask = 0;
1066 			warning("%s", ebuf);
1067 		}
1068 	}
1069 	if (infile)
1070 		cmdbuf = read_infile(infile);
1071 	else
1072 		cmdbuf = copy_argv(&argv[optind]);
1073 
1074 	if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
1075 		error("%s", pcap_geterr(pd));
1076 	if (dflag) {
1077 		bpf_dump(&fcode, dflag);
1078 		pcap_close(pd);
1079 		exit(0);
1080 	}
1081 	init_addrtoname(localnet, netmask);
1082         init_checksum();
1083 
1084 #ifndef WIN32
1085 	(void)setsignal(SIGPIPE, cleanup);
1086 	(void)setsignal(SIGTERM, cleanup);
1087 	(void)setsignal(SIGINT, cleanup);
1088 	(void)setsignal(SIGCHLD, child_cleanup);
1089 #endif /* WIN32 */
1090 	/* Cooperate with nohup(1) */
1091 #ifndef WIN32
1092 	if ((oldhandler = setsignal(SIGHUP, cleanup)) != SIG_DFL)
1093 		(void)setsignal(SIGHUP, oldhandler);
1094 #endif /* WIN32 */
1095 
1096 	if (pcap_setfilter(pd, &fcode) < 0)
1097 		error("%s", pcap_geterr(pd));
1098 	if (WFileName) {
1099 		pcap_dumper_t *p;
1100 		/* Do not exceed the default NAME_MAX for files. */
1101 		dumpinfo.CurrentFileName = (char *)malloc(NAME_MAX + 1);
1102 
1103 		if (dumpinfo.CurrentFileName == NULL)
1104 			error("malloc of dumpinfo.CurrentFileName");
1105 
1106 		/* We do not need numbering for dumpfiles if Cflag isn't set. */
1107 		if (Cflag != 0)
1108 		  MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, WflagChars);
1109 		else
1110 		  MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, 0);
1111 
1112 		p = pcap_dump_open(pd, dumpinfo.CurrentFileName);
1113 		if (p == NULL)
1114 			error("%s", pcap_geterr(pd));
1115 		if (Cflag != 0 || Gflag != 0) {
1116 			callback = dump_packet_and_trunc;
1117 			dumpinfo.WFileName = WFileName;
1118 			dumpinfo.pd = pd;
1119 			dumpinfo.p = p;
1120 			pcap_userdata = (u_char *)&dumpinfo;
1121 		} else {
1122 			callback = dump_packet;
1123 			pcap_userdata = (u_char *)p;
1124 		}
1125 	} else {
1126 		type = pcap_datalink(pd);
1127 		printinfo.printer = lookup_printer(type);
1128 		if (printinfo.printer == NULL) {
1129 			gndo->ndo_dltname = pcap_datalink_val_to_name(type);
1130 			if (gndo->ndo_dltname != NULL)
1131 				error("unsupported data link type %s",
1132 				      gndo->ndo_dltname);
1133 			else
1134 				error("unsupported data link type %d", type);
1135 		}
1136 		callback = print_packet;
1137 		pcap_userdata = (u_char *)&printinfo;
1138 	}
1139 #ifndef WIN32
1140 	/*
1141 	 * We cannot do this earlier, because we want to be able to open
1142 	 * the file (if done) for writing before giving up permissions.
1143 	 */
1144 	if (getuid() == 0 || geteuid() == 0) {
1145 		if (username || chroot_dir)
1146 			droproot(username, chroot_dir);
1147 	}
1148 #endif /* WIN32 */
1149 #ifdef SIGINFO
1150 	/*
1151 	 * We can't get statistics when reading from a file rather
1152 	 * than capturing from a device.
1153 	 */
1154 	if (RFileName == NULL)
1155 		(void)setsignal(SIGINFO, requestinfo);
1156 #endif
1157 
1158 	if (vflag > 0 && WFileName) {
1159 		/*
1160 		 * When capturing to a file, "-v" means tcpdump should,
1161 		 * every 10 secodns, "v"erbosely report the number of
1162 		 * packets captured.
1163 		 */
1164 #ifdef USE_WIN32_MM_TIMER
1165 		/* call verbose_stats_dump() each 1000 +/-100msec */
1166 		timer_id = timeSetEvent(1000, 100, verbose_stats_dump, 0, TIME_PERIODIC);
1167 		setvbuf(stderr, NULL, _IONBF, 0);
1168 #elif defined(HAVE_ALARM)
1169 		(void)setsignal(SIGALRM, verbose_stats_dump);
1170 		alarm(1);
1171 #endif
1172 	}
1173 
1174 #ifndef WIN32
1175 	if (RFileName == NULL) {
1176 		int dlt;
1177 		const char *dlt_name;
1178 
1179 		if (!vflag && !WFileName) {
1180 			(void)fprintf(stderr,
1181 			    "%s: verbose output suppressed, use -v or -vv for full protocol decode\n",
1182 			    program_name);
1183 		} else
1184 			(void)fprintf(stderr, "%s: ", program_name);
1185 		dlt = pcap_datalink(pd);
1186 		dlt_name = pcap_datalink_val_to_name(dlt);
1187 		if (dlt_name == NULL) {
1188 			(void)fprintf(stderr, "listening on %s, link-type %u, capture size %u bytes\n",
1189 			    device, dlt, snaplen);
1190 		} else {
1191 			(void)fprintf(stderr, "listening on %s, link-type %s (%s), capture size %u bytes\n",
1192 			    device, dlt_name,
1193 			    pcap_datalink_val_to_description(dlt), snaplen);
1194 		}
1195 		(void)fflush(stderr);
1196 	}
1197 #endif /* WIN32 */
1198 	status = pcap_loop(pd, cnt, callback, pcap_userdata);
1199 	if (WFileName == NULL) {
1200 		/*
1201 		 * We're printing packets.  Flush the printed output,
1202 		 * so it doesn't get intermingled with error output.
1203 		 */
1204 		if (status == -2) {
1205 			/*
1206 			 * We got interrupted, so perhaps we didn't
1207 			 * manage to finish a line we were printing.
1208 			 * Print an extra newline, just in case.
1209 			 */
1210 			putchar('\n');
1211 		}
1212 		(void)fflush(stdout);
1213 	}
1214 	if (status == -1) {
1215 		/*
1216 		 * Error.  Report it.
1217 		 */
1218 		(void)fprintf(stderr, "%s: pcap_loop: %s\n",
1219 		    program_name, pcap_geterr(pd));
1220 	}
1221 	if (RFileName == NULL) {
1222 		/*
1223 		 * We're doing a live capture.  Report the capture
1224 		 * statistics.
1225 		 */
1226 		info(1);
1227 	}
1228 	pcap_close(pd);
1229 	exit(status == -1 ? 1 : 0);
1230 }
1231 
1232 /* make a clean exit on interrupts */
1233 static RETSIGTYPE
1234 cleanup(int signo _U_)
1235 {
1236 #ifdef USE_WIN32_MM_TIMER
1237 	if (timer_id)
1238 		timeKillEvent(timer_id);
1239 	timer_id = 0;
1240 #elif defined(HAVE_ALARM)
1241 	alarm(0);
1242 #endif
1243 
1244 #ifdef HAVE_PCAP_BREAKLOOP
1245 	/*
1246 	 * We have "pcap_breakloop()"; use it, so that we do as little
1247 	 * as possible in the signal handler (it's probably not safe
1248 	 * to do anything with standard I/O streams in a signal handler -
1249 	 * the ANSI C standard doesn't say it is).
1250 	 */
1251 	pcap_breakloop(pd);
1252 #else
1253 	/*
1254 	 * We don't have "pcap_breakloop()"; this isn't safe, but
1255 	 * it's the best we can do.  Print the summary if we're
1256 	 * not reading from a savefile - i.e., if we're doing a
1257 	 * live capture - and exit.
1258 	 */
1259 	if (pd != NULL && pcap_file(pd) == NULL) {
1260 		/*
1261 		 * We got interrupted, so perhaps we didn't
1262 		 * manage to finish a line we were printing.
1263 		 * Print an extra newline, just in case.
1264 		 */
1265 		putchar('\n');
1266 		(void)fflush(stdout);
1267 		info(1);
1268 	}
1269 	exit(0);
1270 #endif
1271 }
1272 
1273 /*
1274   On windows, we do not use a fork, so we do not care less about
1275   waiting a child processes to die
1276  */
1277 #ifndef WIN32
1278 static RETSIGTYPE
1279 child_cleanup(int signo _U_)
1280 {
1281   wait(NULL);
1282 }
1283 #endif /* WIN32 */
1284 
1285 static void
1286 info(register int verbose)
1287 {
1288 	struct pcap_stat stat;
1289 
1290 	if (pcap_stats(pd, &stat) < 0) {
1291 		(void)fprintf(stderr, "pcap_stats: %s\n", pcap_geterr(pd));
1292 		infoprint = 0;
1293 		return;
1294 	}
1295 
1296 	if (!verbose)
1297 		fprintf(stderr, "%s: ", program_name);
1298 
1299 	(void)fprintf(stderr, "%u packets captured", packets_captured);
1300 	if (!verbose)
1301 		fputs(", ", stderr);
1302 	else
1303 		putc('\n', stderr);
1304 	(void)fprintf(stderr, "%d packets received by filter", stat.ps_recv);
1305 	if (!verbose)
1306 		fputs(", ", stderr);
1307 	else
1308 		putc('\n', stderr);
1309 	(void)fprintf(stderr, "%d packets dropped by kernel\n", stat.ps_drop);
1310 	infoprint = 0;
1311 }
1312 
1313 #ifndef WIN32
1314 static void
1315 compress_savefile(const char *filename)
1316 {
1317 	if (fork())
1318 		return;
1319 	/*
1320 	 * Set to lowest priority so that this doesn't disturb the capture
1321 	 */
1322 #ifdef NZERO
1323 	setpriority(PRIO_PROCESS, 0, NZERO - 1);
1324 #else
1325 	setpriority(PRIO_PROCESS, 0, 19);
1326 #endif
1327 	if (execlp(zflag, zflag, filename, NULL) == -1)
1328 		fprintf(stderr,
1329 			"compress_savefile:execlp(%s, %s): %s\n",
1330 			zflag,
1331 			filename,
1332 			strerror(errno));
1333 }
1334 #else  /* WIN32 */
1335 static void
1336 compress_savefile(const char *filename)
1337 {
1338 	fprintf(stderr,
1339 		"compress_savefile failed. Functionality not implemented under windows\n");
1340 }
1341 #endif /* WIN32 */
1342 
1343 static void
1344 dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1345 {
1346 	struct dump_info *dump_info;
1347 
1348 	++packets_captured;
1349 
1350 	++infodelay;
1351 
1352 	dump_info = (struct dump_info *)user;
1353 
1354 	/*
1355 	 * XXX - this won't force the file to rotate on the specified time
1356 	 * boundary, but it will rotate on the first packet received after the
1357 	 * specified Gflag number of seconds. Note: if a Gflag time boundary
1358 	 * and a Cflag size boundary coincide, the time rotation will occur
1359 	 * first thereby cancelling the Cflag boundary (since the file should
1360 	 * be 0).
1361 	 */
1362 	if (Gflag != 0) {
1363 		/* Check if it is time to rotate */
1364 		time_t t;
1365 
1366 		/* Get the current time */
1367 		if ((t = time(NULL)) == (time_t)-1) {
1368 			error("dump_and_trunc_packet: can't get current_time: %s",
1369 			    pcap_strerror(errno));
1370 		}
1371 
1372 
1373 		/* If the time is greater than the specified window, rotate */
1374 		if (t - Gflag_time >= Gflag) {
1375 			/* Update the Gflag_time */
1376 			Gflag_time = t;
1377 			/* Update Gflag_count */
1378 			Gflag_count++;
1379 			/*
1380 			 * Close the current file and open a new one.
1381 			 */
1382 			pcap_dump_close(dump_info->p);
1383 
1384 			/*
1385 			 * Compress the file we just closed, if the user asked for it
1386 			 */
1387 			if (zflag != NULL)
1388 				compress_savefile(dump_info->CurrentFileName);
1389 
1390 			/*
1391 			 * Check to see if we've exceeded the Wflag (when
1392 			 * not using Cflag).
1393 			 */
1394 			if (Cflag == 0 && Wflag > 0 && Gflag_count >= Wflag) {
1395 				(void)fprintf(stderr, "Maximum file limit reached: %d\n",
1396 				    Wflag);
1397 				exit(0);
1398 				/* NOTREACHED */
1399 			}
1400 			if (dump_info->CurrentFileName != NULL)
1401 				free(dump_info->CurrentFileName);
1402 			/* Allocate space for max filename + \0. */
1403 			dump_info->CurrentFileName = (char *)malloc(NAME_MAX + 1);
1404 			if (dump_info->CurrentFileName == NULL)
1405 				error("dump_packet_and_trunc: malloc");
1406 			/*
1407 			 * This is always the first file in the Cflag
1408 			 * rotation: e.g. 0
1409 			 * We also don't need numbering if Cflag is not set.
1410 			 */
1411 			if (Cflag != 0)
1412 				MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0,
1413 				    WflagChars);
1414 			else
1415 				MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0, 0);
1416 
1417 			dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
1418 			if (dump_info->p == NULL)
1419 				error("%s", pcap_geterr(pd));
1420 		}
1421 	}
1422 
1423 	/*
1424 	 * XXX - this won't prevent capture files from getting
1425 	 * larger than Cflag - the last packet written to the
1426 	 * file could put it over Cflag.
1427 	 */
1428 	if (Cflag != 0 && pcap_dump_ftell(dump_info->p) > Cflag) {
1429 		/*
1430 		 * Close the current file and open a new one.
1431 		 */
1432 		pcap_dump_close(dump_info->p);
1433 
1434 		/*
1435 		 * Compress the file we just closed, if the user asked for it
1436 		 */
1437 		if (zflag != NULL)
1438 			compress_savefile(dump_info->CurrentFileName);
1439 
1440 		Cflag_count++;
1441 		if (Wflag > 0) {
1442 			if (Cflag_count >= Wflag)
1443 				Cflag_count = 0;
1444 		}
1445 		if (dump_info->CurrentFileName != NULL)
1446 			free(dump_info->CurrentFileName);
1447 		dump_info->CurrentFileName = (char *)malloc(NAME_MAX + 1);
1448 		if (dump_info->CurrentFileName == NULL)
1449 			error("dump_packet_and_trunc: malloc");
1450 		MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, Cflag_count, WflagChars);
1451 		dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
1452 		if (dump_info->p == NULL)
1453 			error("%s", pcap_geterr(pd));
1454 	}
1455 
1456 	pcap_dump((u_char *)dump_info->p, h, sp);
1457 #ifdef HAVE_PCAP_DUMP_FLUSH
1458 	if (Uflag)
1459 		pcap_dump_flush(dump_info->p);
1460 #endif
1461 
1462 	--infodelay;
1463 	if (infoprint)
1464 		info(0);
1465 }
1466 
1467 static void
1468 dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1469 {
1470 	++packets_captured;
1471 
1472 	++infodelay;
1473 
1474 	pcap_dump(user, h, sp);
1475 #ifdef HAVE_PCAP_DUMP_FLUSH
1476 	if (Uflag)
1477 		pcap_dump_flush((pcap_dumper_t *)user);
1478 #endif
1479 
1480 	--infodelay;
1481 	if (infoprint)
1482 		info(0);
1483 }
1484 
1485 static void
1486 print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1487 {
1488 	struct print_info *print_info;
1489 	u_int hdrlen;
1490 
1491 	++packets_captured;
1492 
1493 	++infodelay;
1494 	ts_print(&h->ts);
1495 
1496 	print_info = (struct print_info *)user;
1497 
1498 	/*
1499 	 * Some printers want to check that they're not walking off the
1500 	 * end of the packet.
1501 	 * Rather than pass it all the way down, we set this global.
1502 	 */
1503 	snapend = sp + h->caplen;
1504 
1505 	hdrlen = (*print_info->printer)(h, sp);
1506 	if (Xflag) {
1507 		/*
1508 		 * Print the raw packet data in hex and ASCII.
1509 		 */
1510 		if (Xflag > 1) {
1511 			/*
1512 			 * Include the link-layer header.
1513 			 */
1514 			hex_and_ascii_print("\n\t", sp, h->caplen);
1515 		} else {
1516 			/*
1517 			 * Don't include the link-layer header - and if
1518 			 * we have nothing past the link-layer header,
1519 			 * print nothing.
1520 			 */
1521 			if (h->caplen > hdrlen)
1522 				hex_and_ascii_print("\n\t", sp + hdrlen,
1523 				    h->caplen - hdrlen);
1524 		}
1525 	} else if (xflag) {
1526 		/*
1527 		 * Print the raw packet data in hex.
1528 		 */
1529 		if (xflag > 1) {
1530 			/*
1531 			 * Include the link-layer header.
1532 			 */
1533 			hex_print("\n\t", sp, h->caplen);
1534 		} else {
1535 			/*
1536 			 * Don't include the link-layer header - and if
1537 			 * we have nothing past the link-layer header,
1538 			 * print nothing.
1539 			 */
1540 			if (h->caplen > hdrlen)
1541 				hex_print("\n\t", sp + hdrlen,
1542 				    h->caplen - hdrlen);
1543 		}
1544 	} else if (Aflag) {
1545 		/*
1546 		 * Print the raw packet data in ASCII.
1547 		 */
1548 		if (Aflag > 1) {
1549 			/*
1550 			 * Include the link-layer header.
1551 			 */
1552 			ascii_print(sp, h->caplen);
1553 		} else {
1554 			/*
1555 			 * Don't include the link-layer header - and if
1556 			 * we have nothing past the link-layer header,
1557 			 * print nothing.
1558 			 */
1559 			if (h->caplen > hdrlen)
1560 				ascii_print(sp + hdrlen, h->caplen - hdrlen);
1561 		}
1562 	}
1563 
1564 	putchar('\n');
1565 
1566 	--infodelay;
1567 	if (infoprint)
1568 		info(0);
1569 }
1570 
1571 #ifdef WIN32
1572 	/*
1573 	 * XXX - there should really be libpcap calls to get the version
1574 	 * number as a string (the string would be generated from #defines
1575 	 * at run time, so that it's not generated from string constants
1576 	 * in the library, as, on many UNIX systems, those constants would
1577 	 * be statically linked into the application executable image, and
1578 	 * would thus reflect the version of libpcap on the system on
1579 	 * which the application was *linked*, not the system on which it's
1580 	 * *running*.
1581 	 *
1582 	 * That routine should be documented, unlike the "version[]"
1583 	 * string, so that UNIX vendors providing their own libpcaps
1584 	 * don't omit it (as a couple of vendors have...).
1585 	 *
1586 	 * Packet.dll should perhaps also export a routine to return the
1587 	 * version number of the Packet.dll code, to supply the
1588 	 * "Wpcap_version" information on Windows.
1589 	 */
1590 	char WDversion[]="current-cvs.tcpdump.org";
1591 #if !defined(HAVE_GENERATED_VERSION)
1592 	char version[]="current-cvs.tcpdump.org";
1593 #endif
1594 	char pcap_version[]="current-cvs.tcpdump.org";
1595 	char Wpcap_version[]="3.1";
1596 #endif
1597 
1598 /*
1599  * By default, print the specified data out in hex and ASCII.
1600  */
1601 static void
1602 ndo_default_print(netdissect_options *ndo _U_, const u_char *bp, u_int length)
1603 {
1604 	hex_and_ascii_print("\n\t", bp, length); /* pass on lf and identation string */
1605 }
1606 
1607 void
1608 default_print(const u_char *bp, u_int length)
1609 {
1610 	ndo_default_print(gndo, bp, length);
1611 }
1612 
1613 #ifdef SIGINFO
1614 RETSIGTYPE requestinfo(int signo _U_)
1615 {
1616 	if (infodelay)
1617 		++infoprint;
1618 	else
1619 		info(0);
1620 }
1621 #endif
1622 
1623 /*
1624  * Called once each second in verbose mode while dumping to file
1625  */
1626 #ifdef USE_WIN32_MM_TIMER
1627 void CALLBACK verbose_stats_dump (UINT timer_id _U_, UINT msg _U_, DWORD_PTR arg _U_,
1628 				  DWORD_PTR dw1 _U_, DWORD_PTR dw2 _U_)
1629 {
1630 	struct pcap_stat stat;
1631 
1632 	if (infodelay == 0 && pcap_stats(pd, &stat) >= 0)
1633 		fprintf(stderr, "Got %u\r", packets_captured);
1634 }
1635 #elif defined(HAVE_ALARM)
1636 static void verbose_stats_dump(int sig _U_)
1637 {
1638 	struct pcap_stat stat;
1639 
1640 	if (infodelay == 0 && pcap_stats(pd, &stat) >= 0)
1641 		fprintf(stderr, "Got %u\r", packets_captured);
1642 	alarm(1);
1643 }
1644 #endif
1645 
1646 static void
1647 usage(void)
1648 {
1649 	extern char version[];
1650 #ifndef HAVE_PCAP_LIB_VERSION
1651 #if defined(WIN32) || defined(HAVE_PCAP_VERSION)
1652 	extern char pcap_version[];
1653 #else /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
1654 	static char pcap_version[] = "unknown";
1655 #endif /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
1656 #endif /* HAVE_PCAP_LIB_VERSION */
1657 
1658 #ifdef HAVE_PCAP_LIB_VERSION
1659 #ifdef WIN32
1660 	(void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
1661 #else /* WIN32 */
1662 	(void)fprintf(stderr, "%s version %s\n", program_name, version);
1663 #endif /* WIN32 */
1664 	(void)fprintf(stderr, "%s\n",pcap_lib_version());
1665 #else /* HAVE_PCAP_LIB_VERSION */
1666 #ifdef WIN32
1667 	(void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
1668 	(void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version);
1669 #else /* WIN32 */
1670 	(void)fprintf(stderr, "%s version %s\n", program_name, version);
1671 	(void)fprintf(stderr, "libpcap version %s\n", pcap_version);
1672 #endif /* WIN32 */
1673 #endif /* HAVE_PCAP_LIB_VERSION */
1674 	(void)fprintf(stderr,
1675 "Usage: %s [-aAd" D_FLAG "ef" I_FLAG "KlLnNOpqRStu" U_FLAG "vxX]" B_FLAG_USAGE " [ -c count ]\n", program_name);
1676 	(void)fprintf(stderr,
1677 "\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n");
1678 	(void)fprintf(stderr,
1679 "\t\t[ -i interface ] [ -M secret ] [ -r file ]\n");
1680 	(void)fprintf(stderr,
1681 "\t\t[ -s snaplen ] [ -T type ] [ -w file ] [ -W filecount ]\n");
1682 	(void)fprintf(stderr,
1683 "\t\t[ -y datalinktype ] [ -z command ] [ -Z user ]\n");
1684 	(void)fprintf(stderr,
1685 "\t\t[ expression ]\n");
1686 	exit(1);
1687 }
1688 
1689 
1690 
1691 /* VARARGS */
1692 static void
1693 ndo_error(netdissect_options *ndo _U_, const char *fmt, ...)
1694 {
1695 	va_list ap;
1696 
1697 	(void)fprintf(stderr, "%s: ", program_name);
1698 	va_start(ap, fmt);
1699 	(void)vfprintf(stderr, fmt, ap);
1700 	va_end(ap);
1701 	if (*fmt) {
1702 		fmt += strlen(fmt);
1703 		if (fmt[-1] != '\n')
1704 			(void)fputc('\n', stderr);
1705 	}
1706 	exit(1);
1707 	/* NOTREACHED */
1708 }
1709 
1710 /* VARARGS */
1711 static void
1712 ndo_warning(netdissect_options *ndo _U_, const char *fmt, ...)
1713 {
1714 	va_list ap;
1715 
1716 	(void)fprintf(stderr, "%s: WARNING: ", program_name);
1717 	va_start(ap, fmt);
1718 	(void)vfprintf(stderr, fmt, ap);
1719 	va_end(ap);
1720 	if (*fmt) {
1721 		fmt += strlen(fmt);
1722 		if (fmt[-1] != '\n')
1723 			(void)fputc('\n', stderr);
1724 	}
1725 }
1726