xref: /netbsd-src/external/bsd/tcpdump/dist/tcpdump.c (revision 6cf6fe02a981b55727c49c3d37b0d8191a98c0ee)
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 #include <sys/cdefs.h>
29 #ifndef lint
30 #if 0
31 static const char copyright[] _U_ =
32     "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
33 The Regents of the University of California.  All rights reserved.\n";
34 static const char rcsid[] _U_ =
35     "@(#) Header: /tcpdump/master/tcpdump/tcpdump.c,v 1.283 2008-09-25 21:45:50 guy Exp  (LBL)";
36 #else
37 __RCSID("$NetBSD: tcpdump.c,v 1.8 2014/05/13 20:29:59 christos Exp $");
38 #endif
39 #endif
40 
41 /*
42  * tcpdump - monitor tcp/ip traffic on an ethernet.
43  *
44  * First written in 1987 by Van Jacobson, Lawrence Berkeley Laboratory.
45  * Mercilessly hacked and occasionally improved since then via the
46  * combined efforts of Van, Steve McCanne and Craig Leres of LBL.
47  */
48 
49 #ifdef HAVE_CONFIG_H
50 #include "config.h"
51 #endif
52 
53 #include <tcpdump-stdinc.h>
54 
55 #ifdef WIN32
56 #include "getopt.h"
57 #include "w32_fzs.h"
58 extern int strcasecmp (const char *__s1, const char *__s2);
59 extern int SIZE_BUF;
60 #define off_t long
61 #define uint UINT
62 #endif /* WIN32 */
63 
64 #ifdef HAVE_SMI_H
65 #include <smi.h>
66 #endif
67 
68 #include <pcap.h>
69 #include <signal.h>
70 #include <stdio.h>
71 #include <stdlib.h>
72 #include <string.h>
73 #include <limits.h>
74 #include <resolv.h>
75 #ifndef WIN32
76 #include <sys/wait.h>
77 #include <sys/resource.h>
78 #include <pwd.h>
79 #include <grp.h>
80 #include <errno.h>
81 #endif /* WIN32 */
82 
83 /* capabilities convinience library */
84 #ifdef HAVE_CAP_NG_H
85 #include <cap-ng.h>
86 #endif /* HAVE_CAP_NG_H */
87 
88 #include "netdissect.h"
89 #include "interface.h"
90 #include "addrtoname.h"
91 #include "machdep.h"
92 #include "setsignal.h"
93 #include "gmt2local.h"
94 #include "pcap-missing.h"
95 
96 #ifndef PATH_MAX
97 #define PATH_MAX 1024
98 #endif
99 
100 #ifdef SIGINFO
101 #define SIGNAL_REQ_INFO SIGINFO
102 #elif SIGUSR1
103 #define SIGNAL_REQ_INFO SIGUSR1
104 #endif
105 
106 netdissect_options Gndo;
107 netdissect_options *gndo = &Gndo;
108 
109 static int dflag;			/* print filter code */
110 static int Lflag;			/* list available data link types and exit */
111 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
112 static int Jflag;			/* list available time stamp types */
113 #endif
114 #ifdef HAVE_PCAP_SETDIRECTION
115 int Pflag = -1;	/* Restrict captured packet by sent/receive direction */
116 #endif
117 static char *zflag = NULL;		/* compress each savefile using a specified command (like gzip or bzip2) */
118 
119 static int infodelay;
120 static int infoprint;
121 
122 char *program_name;
123 
124 int32_t thiszone;		/* seconds offset from gmt to local time */
125 
126 /* Forwards */
127 static RETSIGTYPE cleanup(int);
128 static RETSIGTYPE child_cleanup(int);
129 static void usage(void) __attribute__((noreturn));
130 static void show_dlts_and_exit(const char *device, pcap_t *pd) __attribute__((noreturn));
131 
132 static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
133 static void ndo_default_print(netdissect_options *, const u_char *, u_int);
134 static void dump_packet_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *);
135 static void dump_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
136 static void droproot(const char *, const char *);
137 static void ndo_error(netdissect_options *ndo, const char *fmt, ...)
138      __attribute__ ((noreturn, format (printf, 2, 3)));
139 static void ndo_warning(netdissect_options *ndo, const char *fmt, ...);
140 
141 #ifdef SIGNAL_REQ_INFO
142 RETSIGTYPE requestinfo(int);
143 #endif
144 
145 #if defined(USE_WIN32_MM_TIMER)
146   #include <MMsystem.h>
147   static UINT timer_id;
148   static void CALLBACK verbose_stats_dump(UINT, UINT, DWORD_PTR, DWORD_PTR, DWORD_PTR);
149 #elif defined(HAVE_ALARM)
150   static void verbose_stats_dump(int sig);
151 #endif
152 
153 static void info(int);
154 static u_int packets_captured;
155 
156 struct printer {
157         if_printer f;
158 	int type;
159 };
160 
161 
162 struct ndo_printer {
163         if_ndo_printer f;
164 	int type;
165 };
166 
167 
168 static struct printer printers[] = {
169 	{ arcnet_if_print,	DLT_ARCNET },
170 #ifdef DLT_ARCNET_LINUX
171 	{ arcnet_linux_if_print, DLT_ARCNET_LINUX },
172 #endif
173 	{ token_if_print,	DLT_IEEE802 },
174 #ifdef DLT_LANE8023
175 	{ lane_if_print,        DLT_LANE8023 },
176 #endif
177 #ifdef DLT_CIP
178 	{ cip_if_print,         DLT_CIP },
179 #endif
180 #ifdef DLT_ATM_CLIP
181 	{ cip_if_print,		DLT_ATM_CLIP },
182 #endif
183 	{ sl_if_print,		DLT_SLIP },
184 #ifdef DLT_SLIP_BSDOS
185 	{ sl_bsdos_if_print,	DLT_SLIP_BSDOS },
186 #endif
187 	{ ppp_if_print,		DLT_PPP },
188 #ifdef DLT_PPP_WITHDIRECTION
189 	{ ppp_if_print,		DLT_PPP_WITHDIRECTION },
190 #endif
191 #ifdef DLT_PPP_BSDOS
192 	{ ppp_bsdos_if_print,	DLT_PPP_BSDOS },
193 #endif
194 	{ fddi_if_print,	DLT_FDDI },
195 	{ null_if_print,	DLT_NULL },
196 #ifdef DLT_LOOP
197 	{ null_if_print,	DLT_LOOP },
198 #endif
199 	{ raw_if_print,		DLT_RAW },
200 	{ atm_if_print,		DLT_ATM_RFC1483 },
201 #ifdef DLT_C_HDLC
202 	{ chdlc_if_print,	DLT_C_HDLC },
203 #endif
204 #ifdef DLT_HDLC
205 	{ chdlc_if_print,	DLT_HDLC },
206 #endif
207 #ifdef DLT_PPP_SERIAL
208 	{ ppp_hdlc_if_print,	DLT_PPP_SERIAL },
209 #endif
210 #ifdef DLT_PPP_ETHER
211 	{ pppoe_if_print,	DLT_PPP_ETHER },
212 #endif
213 #ifdef DLT_LINUX_SLL
214 	{ sll_if_print,		DLT_LINUX_SLL },
215 #endif
216 #ifdef DLT_IEEE802_11
217 	{ ieee802_11_if_print,	DLT_IEEE802_11},
218 #endif
219 #ifdef DLT_LTALK
220 	{ ltalk_if_print,	DLT_LTALK },
221 #endif
222 #if defined(DLT_PFLOG) && defined(HAVE_NET_PFVAR_H)
223 	{ pflog_if_print,	DLT_PFLOG },
224 #endif
225 #ifdef DLT_PFSYNC
226 	{ pfsync_if_print,  DLT_PFSYNC },
227 #endif
228 #ifdef DLT_FR
229 	{ fr_if_print,		DLT_FR },
230 #endif
231 #ifdef DLT_FRELAY
232 	{ fr_if_print,		DLT_FRELAY },
233 #endif
234 #ifdef DLT_SUNATM
235 	{ sunatm_if_print,	DLT_SUNATM },
236 #endif
237 #ifdef DLT_IP_OVER_FC
238 	{ ipfc_if_print,	DLT_IP_OVER_FC },
239 #endif
240 #ifdef DLT_PRISM_HEADER
241 	{ prism_if_print,	DLT_PRISM_HEADER },
242 #endif
243 #ifdef DLT_IEEE802_11_RADIO
244 	{ ieee802_11_radio_if_print,	DLT_IEEE802_11_RADIO },
245 #endif
246 #ifdef DLT_ENC
247 	{ enc_if_print,		DLT_ENC },
248 #endif
249 #ifdef DLT_SYMANTEC_FIREWALL
250 	{ symantec_if_print,	DLT_SYMANTEC_FIREWALL },
251 #endif
252 #ifdef DLT_APPLE_IP_OVER_IEEE1394
253 	{ ap1394_if_print,	DLT_APPLE_IP_OVER_IEEE1394 },
254 #endif
255 #ifdef DLT_IEEE802_11_RADIO_AVS
256 	{ ieee802_11_radio_avs_if_print,	DLT_IEEE802_11_RADIO_AVS },
257 #endif
258 #ifdef DLT_JUNIPER_ATM1
259 	{ juniper_atm1_print,	DLT_JUNIPER_ATM1 },
260 #endif
261 #ifdef DLT_JUNIPER_ATM2
262 	{ juniper_atm2_print,	DLT_JUNIPER_ATM2 },
263 #endif
264 #ifdef DLT_JUNIPER_MFR
265 	{ juniper_mfr_print,	DLT_JUNIPER_MFR },
266 #endif
267 #ifdef DLT_JUNIPER_MLFR
268 	{ juniper_mlfr_print,	DLT_JUNIPER_MLFR },
269 #endif
270 #ifdef DLT_JUNIPER_MLPPP
271 	{ juniper_mlppp_print,	DLT_JUNIPER_MLPPP },
272 #endif
273 #ifdef DLT_JUNIPER_PPPOE
274 	{ juniper_pppoe_print,	DLT_JUNIPER_PPPOE },
275 #endif
276 #ifdef DLT_JUNIPER_PPPOE_ATM
277 	{ juniper_pppoe_atm_print, DLT_JUNIPER_PPPOE_ATM },
278 #endif
279 #ifdef DLT_JUNIPER_GGSN
280 	{ juniper_ggsn_print,	DLT_JUNIPER_GGSN },
281 #endif
282 #ifdef DLT_JUNIPER_ES
283 	{ juniper_es_print,	DLT_JUNIPER_ES },
284 #endif
285 #ifdef DLT_JUNIPER_MONITOR
286 	{ juniper_monitor_print, DLT_JUNIPER_MONITOR },
287 #endif
288 #ifdef DLT_JUNIPER_SERVICES
289 	{ juniper_services_print, DLT_JUNIPER_SERVICES },
290 #endif
291 #ifdef DLT_JUNIPER_ETHER
292 	{ juniper_ether_print,	DLT_JUNIPER_ETHER },
293 #endif
294 #ifdef DLT_JUNIPER_PPP
295 	{ juniper_ppp_print,	DLT_JUNIPER_PPP },
296 #endif
297 #ifdef DLT_JUNIPER_FRELAY
298 	{ juniper_frelay_print,	DLT_JUNIPER_FRELAY },
299 #endif
300 #ifdef DLT_JUNIPER_CHDLC
301 	{ juniper_chdlc_print,	DLT_JUNIPER_CHDLC },
302 #endif
303 #ifdef DLT_MFR
304 	{ mfr_if_print,		DLT_MFR },
305 #endif
306 #if defined(DLT_BLUETOOTH_HCI_H4_WITH_PHDR) && defined(HAVE_PCAP_BLUETOOTH_H)
307 	{ bt_if_print,		DLT_BLUETOOTH_HCI_H4_WITH_PHDR},
308 #endif
309 #ifdef HAVE_PCAP_USB_H
310 #ifdef DLT_USB_LINUX
311 	{ usb_linux_48_byte_print, DLT_USB_LINUX},
312 #endif /* DLT_USB_LINUX */
313 #ifdef DLT_USB_LINUX_MMAPPED
314 	{ usb_linux_64_byte_print, DLT_USB_LINUX_MMAPPED},
315 #endif /* DLT_USB_LINUX_MMAPPED */
316 #endif /* HAVE_PCAP_USB_H */
317 #ifdef DLT_IPV4
318 	{ raw_if_print,		DLT_IPV4 },
319 #endif
320 #ifdef DLT_IPV6
321 	{ raw_if_print,		DLT_IPV6 },
322 #endif
323 	{ NULL,			0 },
324 };
325 
326 static struct ndo_printer ndo_printers[] = {
327 	{ ether_if_print,	DLT_EN10MB },
328 #ifdef DLT_IPNET
329 	{ ipnet_if_print,	DLT_IPNET },
330 #endif
331 #ifdef DLT_IEEE802_15_4
332 	{ ieee802_15_4_if_print, DLT_IEEE802_15_4 },
333 #endif
334 #ifdef DLT_IEEE802_15_4_NOFCS
335 	{ ieee802_15_4_if_print, DLT_IEEE802_15_4_NOFCS },
336 #endif
337 #ifdef DLT_PPI
338 	{ ppi_if_print,		DLT_PPI },
339 #endif
340 #ifdef DLT_NETANALYZER
341 	{ netanalyzer_if_print, DLT_NETANALYZER },
342 #endif
343 #ifdef DLT_NETANALYZER_TRANSPARENT
344 	{ netanalyzer_transparent_if_print, DLT_NETANALYZER_TRANSPARENT },
345 #endif
346 #ifdef DLT_NFLOG
347 	{ nflog_if_print,	DLT_NFLOG},
348 #endif
349 	{ NULL,			0 },
350 };
351 
352 if_printer
353 lookup_printer(int type)
354 {
355 	struct printer *p;
356 
357 	for (p = printers; p->f; ++p)
358 		if (type == p->type)
359 			return p->f;
360 
361 	return NULL;
362 	/* NOTREACHED */
363 }
364 
365 if_ndo_printer
366 lookup_ndo_printer(int type)
367 {
368 	struct ndo_printer *p;
369 
370 	for (p = ndo_printers; p->f; ++p)
371 		if (type == p->type)
372 			return p->f;
373 
374 	return NULL;
375 	/* NOTREACHED */
376 }
377 
378 static pcap_t *pd;
379 
380 static int supports_monitor_mode;
381 
382 extern int optind;
383 extern int opterr;
384 extern char *optarg;
385 
386 struct print_info {
387         netdissect_options *ndo;
388         union {
389                 if_printer     printer;
390                 if_ndo_printer ndo_printer;
391         } p;
392         int ndo_type;
393 };
394 
395 struct dump_info {
396 	char	*WFileName;
397 	char	*CurrentFileName;
398 	pcap_t	*pd;
399 	pcap_dumper_t *p;
400 };
401 
402 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
403 static void
404 show_tstamp_types_and_exit(const char *device, pcap_t *pd)
405 {
406 	int n_tstamp_types;
407 	int *tstamp_types = 0;
408 	const char *tstamp_type_name;
409 	int i;
410 
411 	n_tstamp_types = pcap_list_tstamp_types(pd, &tstamp_types);
412 	if (n_tstamp_types < 0)
413 		error("%s", pcap_geterr(pd));
414 
415 	if (n_tstamp_types == 0) {
416 		fprintf(stderr, "Time stamp type cannot be set for %s\n",
417 		    device);
418 		exit(0);
419 	}
420 	fprintf(stderr, "Time stamp types for %s (use option -j to set):\n",
421 	    device);
422 	for (i = 0; i < n_tstamp_types; i++) {
423 		tstamp_type_name = pcap_tstamp_type_val_to_name(tstamp_types[i]);
424 		if (tstamp_type_name != NULL) {
425 			(void) fprintf(stderr, "  %s (%s)\n", tstamp_type_name,
426 			    pcap_tstamp_type_val_to_description(tstamp_types[i]));
427 		} else {
428 			(void) fprintf(stderr, "  %d\n", tstamp_types[i]);
429 		}
430 	}
431 	pcap_free_tstamp_types(tstamp_types);
432 	exit(0);
433 }
434 #endif
435 
436 static void
437 show_dlts_and_exit(const char *device, pcap_t *pd)
438 {
439 	int n_dlts;
440 	int *dlts = 0;
441 	const char *dlt_name;
442 
443 	n_dlts = pcap_list_datalinks(pd, &dlts);
444 	if (n_dlts < 0)
445 		error("%s", pcap_geterr(pd));
446 	else if (n_dlts == 0 || !dlts)
447 		error("No data link types.");
448 
449 	/*
450 	 * If the interface is known to support monitor mode, indicate
451 	 * whether these are the data link types available when not in
452 	 * monitor mode, if -I wasn't specified, or when in monitor mode,
453 	 * when -I was specified (the link-layer types available in
454 	 * monitor mode might be different from the ones available when
455 	 * not in monitor mode).
456 	 */
457 	if (supports_monitor_mode)
458 		(void) fprintf(stderr, "Data link types for %s %s (use option -y to set):\n",
459 		    device,
460 		    Iflag ? "when in monitor mode" : "when not in monitor mode");
461 	else
462 		(void) fprintf(stderr, "Data link types for %s (use option -y to set):\n",
463 		    device);
464 
465 	while (--n_dlts >= 0) {
466 		dlt_name = pcap_datalink_val_to_name(dlts[n_dlts]);
467 		if (dlt_name != NULL) {
468 			(void) fprintf(stderr, "  %s (%s)", dlt_name,
469 			    pcap_datalink_val_to_description(dlts[n_dlts]));
470 
471 			/*
472 			 * OK, does tcpdump handle that type?
473 			 */
474 			if (lookup_printer(dlts[n_dlts]) == NULL
475                             && lookup_ndo_printer(dlts[n_dlts]) == NULL)
476 				(void) fprintf(stderr, " (printing not supported)");
477 			fprintf(stderr, "\n");
478 		} else {
479 			(void) fprintf(stderr, "  DLT %d (printing not supported)\n",
480 			    dlts[n_dlts]);
481 		}
482 	}
483 #ifdef HAVE_PCAP_FREE_DATALINKS
484 	pcap_free_datalinks(dlts);
485 #endif
486 	exit(0);
487 }
488 
489 /*
490  * Set up flags that might or might not be supported depending on the
491  * version of libpcap we're using.
492  */
493 #if defined(HAVE_PCAP_CREATE) || defined(WIN32)
494 #define B_FLAG		"B:"
495 #define B_FLAG_USAGE	" [ -B size ]"
496 #else /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
497 #define B_FLAG
498 #define B_FLAG_USAGE
499 #endif /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
500 
501 #ifdef HAVE_PCAP_CREATE
502 #define I_FLAG		"I"
503 #else /* HAVE_PCAP_CREATE */
504 #define I_FLAG
505 #endif /* HAVE_PCAP_CREATE */
506 
507 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
508 #define j_FLAG		"j:"
509 #define j_FLAG_USAGE	" [ -j tstamptype ]"
510 #define J_FLAG		"J"
511 #else /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */
512 #define j_FLAG
513 #define j_FLAG_USAGE
514 #define J_FLAG
515 #endif /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */
516 
517 #ifdef HAVE_PCAP_FINDALLDEVS
518 #ifndef HAVE_PCAP_IF_T
519 #undef HAVE_PCAP_FINDALLDEVS
520 #endif
521 #endif
522 
523 #ifdef HAVE_PCAP_FINDALLDEVS
524 #define D_FLAG	"D"
525 #else
526 #define D_FLAG
527 #endif
528 
529 #ifdef HAVE_PCAP_DUMP_FLUSH
530 #define U_FLAG	"U"
531 #else
532 #define U_FLAG
533 #endif
534 
535 #ifdef HAVE_PCAP_SETDIRECTION
536 #define P_FLAG "P:"
537 #else
538 #define P_FLAG
539 #endif
540 
541 #ifndef WIN32
542 /* Drop root privileges and chroot if necessary */
543 static void
544 droproot(const char *username, const char *chroot_dir)
545 {
546 	struct passwd *pw = NULL;
547 
548 	if (chroot_dir && !username) {
549 		fprintf(stderr, "tcpdump: Chroot without dropping root is insecure\n");
550 		exit(1);
551 	}
552 
553 	pw = getpwnam(username);
554 	if (pw) {
555 		if (initgroups(pw->pw_name, pw->pw_gid) != 0) {
556 			fprintf(stderr, "tcpdump: Couldn't initgroups to "
557 			    "'%.32s' gid=%lu: %s\n", pw->pw_name,
558 			    (unsigned long)pw->pw_gid,
559 			    pcap_strerror(errno));
560 			exit(1);
561 		}
562 		if (chroot_dir) {
563 			setprotoent(1);
564 			res_init();
565 			if (chroot(chroot_dir) != 0 || chdir ("/") != 0) {
566 				fprintf(stderr, "tcpdump: Couldn't chroot/chdir to '%.64s': %s\n",
567 				    chroot_dir, pcap_strerror(errno));
568 				exit(1);
569 			}
570 		}
571 #ifdef HAVE_CAP_NG_H
572 		int ret = capng_change_id(pw->pw_uid, pw->pw_gid, CAPNG_NO_FLAG);
573 		if (ret < 0) {
574 			printf("error : ret %d\n", ret);
575 		}
576 		/* We don't need CAP_SETUID and CAP_SETGID */
577 		capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_SETUID);
578 		capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_SETUID);
579 		capng_update(CAPNG_DROP, CAPNG_PERMITTED, CAP_SETUID);
580 		capng_update(CAPNG_DROP, CAPNG_PERMITTED, CAP_SETUID);
581 		capng_apply(CAPNG_SELECT_BOTH);
582 
583 #else
584 		if (initgroups(pw->pw_name, pw->pw_gid) != 0 ||
585 		    setgid(pw->pw_gid) != 0 || setuid(pw->pw_uid) != 0) {
586 			fprintf(stderr, "tcpdump: Couldn't change to '%.32s' uid=%lu gid=%lu: %s\n",
587 			    username,
588 			    (unsigned long)pw->pw_uid,
589 			    (unsigned long)pw->pw_gid,
590 			    pcap_strerror(errno));
591 			exit(1);
592 		}
593 #endif /* HAVE_CAP_NG_H */
594 	}
595 	else {
596 		fprintf(stderr, "tcpdump: Couldn't find user '%.32s'\n",
597 		    username);
598 		exit(1);
599 	}
600 }
601 #endif /* WIN32 */
602 
603 static int
604 getWflagChars(int x)
605 {
606 	int c = 0;
607 
608 	x -= 1;
609 	while (x > 0) {
610 		c += 1;
611 		x /= 10;
612 	}
613 
614 	return c;
615 }
616 
617 
618 static void
619 MakeFilename(char *buffer, char *orig_name, int cnt, int max_chars)
620 {
621         char *filename = malloc(PATH_MAX + 1);
622         if (filename == NULL)
623             error("Makefilename: malloc");
624 
625         /* Process with strftime if Gflag is set. */
626         if (Gflag != 0) {
627           struct tm *local_tm;
628 
629           /* Convert Gflag_time to a usable format */
630           if ((local_tm = localtime(&Gflag_time)) == NULL) {
631                   error("MakeTimedFilename: localtime");
632           }
633 
634           /* There's no good way to detect an error in strftime since a return
635            * value of 0 isn't necessarily failure.
636            */
637           strftime(filename, PATH_MAX, orig_name, local_tm);
638         } else {
639           strncpy(filename, orig_name, PATH_MAX);
640         }
641 
642 	if (cnt == 0 && max_chars == 0)
643 		strncpy(buffer, filename, PATH_MAX + 1);
644 	else
645 		if (snprintf(buffer, PATH_MAX + 1, "%s%0*d", filename, max_chars, cnt) > PATH_MAX)
646                   /* Report an error if the filename is too large */
647                   error("too many output files or filename is too long (> %d)", PATH_MAX);
648         free(filename);
649 }
650 
651 static int tcpdump_printf(netdissect_options *ndo _U_,
652 			  const char *fmt, ...)
653 {
654 
655   va_list args;
656   int ret;
657 
658   va_start(args, fmt);
659   ret=vfprintf(stdout, fmt, args);
660   va_end(args);
661 
662   return ret;
663 }
664 
665 static struct print_info
666 get_print_info(int type)
667 {
668 	struct print_info printinfo;
669 
670 	printinfo.ndo_type = 1;
671 	printinfo.ndo = gndo;
672 	printinfo.p.ndo_printer = lookup_ndo_printer(type);
673 	if (printinfo.p.ndo_printer == NULL) {
674 		printinfo.p.printer = lookup_printer(type);
675 		printinfo.ndo_type = 0;
676 		if (printinfo.p.printer == NULL) {
677 			gndo->ndo_dltname = pcap_datalink_val_to_name(type);
678 			if (gndo->ndo_dltname != NULL)
679 				error("packet printing is not supported for link type %s: use -w",
680 				      gndo->ndo_dltname);
681 			else
682 				error("packet printing is not supported for link type %d: use -w", type);
683 		}
684 	}
685 	return (printinfo);
686 }
687 
688 static char *
689 get_next_file(FILE *VFile, char *ptr)
690 {
691 	char *ret;
692 
693 	ret = fgets(ptr, PATH_MAX, VFile);
694 	if (!ret)
695 		return NULL;
696 
697 	if (ptr[strlen(ptr) - 1] == '\n')
698 		ptr[strlen(ptr) - 1] = '\0';
699 
700 	return ret;
701 }
702 
703 int
704 main(int argc, char **argv)
705 {
706 	register int cnt, op, i;
707 	bpf_u_int32 localnet, netmask;
708 	register char *cp, *infile, *cmdbuf, *device, *RFileName, *VFileName, *WFileName;
709 	pcap_handler callback;
710 	int type;
711 	int dlt;
712 	int new_dlt;
713 	const char *dlt_name;
714 	struct bpf_program fcode;
715 #ifndef WIN32
716 	RETSIGTYPE (*oldhandler)(int);
717 #endif
718 	struct print_info printinfo;
719 	struct dump_info dumpinfo;
720 	u_char *pcap_userdata;
721 	char ebuf[PCAP_ERRBUF_SIZE];
722 	char VFileLine[PATH_MAX + 1];
723 	char *username = NULL;
724 	char *chroot_dir = NULL;
725 	char *ret = NULL;
726 	char *end;
727 #ifdef HAVE_PCAP_FINDALLDEVS
728 	pcap_if_t *devpointer;
729 	int devnum;
730 #endif
731 	int status;
732 	FILE *VFile;
733 #ifdef WIN32
734 	if(wsockinit() != 0) return 1;
735 #endif /* WIN32 */
736 
737 	jflag=-1;	/* not set */
738         gndo->ndo_Oflag=1;
739 	gndo->ndo_Rflag=1;
740 	gndo->ndo_dlt=-1;
741 	gndo->ndo_default_print=ndo_default_print;
742 	gndo->ndo_printf=tcpdump_printf;
743 	gndo->ndo_error=ndo_error;
744 	gndo->ndo_warning=ndo_warning;
745 	gndo->ndo_snaplen = DEFAULT_SNAPLEN;
746 
747 	cnt = -1;
748 	device = NULL;
749 	infile = NULL;
750 	RFileName = NULL;
751 	VFileName = NULL;
752 	VFile = NULL;
753 	WFileName = NULL;
754 	dlt = -1;
755 	if ((cp = strrchr(argv[0], '/')) != NULL)
756 		program_name = cp + 1;
757 	else
758 		program_name = argv[0];
759 
760 	if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
761 		error("%s", ebuf);
762 
763 #ifdef LIBSMI
764 	smiInit("tcpdump");
765 #endif
766 
767 	while (
768 	    (op = getopt(argc, argv, "aAb" B_FLAG "c:C:d" D_FLAG "eE:fF:G:hHi:" I_FLAG j_FLAG J_FLAG "KlLm:M:nNOp" P_FLAG "qr:Rs:StT:u" U_FLAG "vV:w:W:xXy:Yz:Z:")) != -1)
769 		switch (op) {
770 
771 		case 'a':
772 			/* compatibility for old -a */
773 			break;
774 
775 		case 'A':
776 			++Aflag;
777 			break;
778 
779 		case 'b':
780 			++bflag;
781 			break;
782 
783 #if defined(HAVE_PCAP_CREATE) || defined(WIN32)
784 		case 'B':
785 			Bflag = atoi(optarg)*1024;
786 			if (Bflag <= 0)
787 				error("invalid packet buffer size %s", optarg);
788 			break;
789 #endif /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
790 
791 		case 'c':
792 			cnt = atoi(optarg);
793 			if (cnt <= 0)
794 				error("invalid packet count %s", optarg);
795 			break;
796 
797 		case 'C':
798 			Cflag = atoi(optarg) * 1000000;
799 			if (Cflag < 0)
800 				error("invalid file size %s", optarg);
801 			break;
802 
803 		case 'd':
804 			++dflag;
805 			break;
806 
807 #ifdef HAVE_PCAP_FINDALLDEVS
808 		case 'D':
809 			if (pcap_findalldevs(&devpointer, ebuf) < 0)
810 				error("%s", ebuf);
811 			else {
812 				for (i = 0; devpointer != 0; i++) {
813 					printf("%d.%s", i+1, devpointer->name);
814 					if (devpointer->description != NULL)
815 						printf(" (%s)", devpointer->description);
816 					printf("\n");
817 					devpointer = devpointer->next;
818 				}
819 			}
820 			return 0;
821 #endif /* HAVE_PCAP_FINDALLDEVS */
822 
823 		case 'L':
824 			Lflag++;
825 			break;
826 
827 		case 'e':
828 			++eflag;
829 			break;
830 
831 		case 'E':
832 #ifndef HAVE_LIBCRYPTO
833 			warning("crypto code not compiled in");
834 #endif
835 			gndo->ndo_espsecret = optarg;
836 			break;
837 
838 		case 'f':
839 			++fflag;
840 			break;
841 
842 		case 'F':
843 			infile = optarg;
844 			break;
845 
846 		case 'G':
847 			Gflag = atoi(optarg);
848 			if (Gflag < 0)
849 				error("invalid number of seconds %s", optarg);
850 
851                         /* We will create one file initially. */
852                         Gflag_count = 0;
853 
854 			/* Grab the current time for rotation use. */
855 			if ((Gflag_time = time(NULL)) == (time_t)-1) {
856 				error("main: can't get current time: %s",
857 				    pcap_strerror(errno));
858 			}
859 			break;
860 
861 		case 'h':
862 			usage();
863 			break;
864 
865 		case 'H':
866 			++Hflag;
867 			break;
868 
869 		case 'i':
870 			if (optarg[0] == '0' && optarg[1] == 0)
871 				error("Invalid adapter index");
872 
873 #ifdef HAVE_PCAP_FINDALLDEVS
874 			/*
875 			 * If the argument is a number, treat it as
876 			 * an index into the list of adapters, as
877 			 * printed by "tcpdump -D".
878 			 *
879 			 * This should be OK on UNIX systems, as interfaces
880 			 * shouldn't have names that begin with digits.
881 			 * It can be useful on Windows, where more than
882 			 * one interface can have the same name.
883 			 */
884 			devnum = strtol(optarg, &end, 10);
885 			if (optarg != end && *end == '\0') {
886 				if (devnum < 0)
887 					error("Invalid adapter index");
888 
889 				if (pcap_findalldevs(&devpointer, ebuf) < 0)
890 					error("%s", ebuf);
891 				else {
892 					/*
893 					 * Look for the devnum-th entry
894 					 * in the list of devices
895 					 * (1-based).
896 					 */
897 					for (i = 0;
898 					    i < devnum-1 && devpointer != NULL;
899 					    i++, devpointer = devpointer->next)
900 						;
901 					if (devpointer == NULL)
902 						error("Invalid adapter index");
903 				}
904 				device = devpointer->name;
905 				break;
906 			}
907 #endif /* HAVE_PCAP_FINDALLDEVS */
908 			device = optarg;
909 			break;
910 
911 #ifdef HAVE_PCAP_CREATE
912 		case 'I':
913 			++Iflag;
914 			break;
915 #endif /* HAVE_PCAP_CREATE */
916 
917 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
918 		case 'j':
919 			jflag = pcap_tstamp_type_name_to_val(optarg);
920 			if (jflag < 0)
921 				error("invalid time stamp type %s", optarg);
922 			break;
923 
924 		case 'J':
925 			Jflag++;
926 			break;
927 #endif
928 
929 		case 'l':
930 #ifdef WIN32
931 			/*
932 			 * _IOLBF is the same as _IOFBF in Microsoft's C
933 			 * libraries; the only alternative they offer
934 			 * is _IONBF.
935 			 *
936 			 * XXX - this should really be checking for MSVC++,
937 			 * not WIN32, if, for example, MinGW has its own
938 			 * C library that is more UNIX-compatible.
939 			 */
940 			setvbuf(stdout, NULL, _IONBF, 0);
941 #else /* WIN32 */
942 #ifdef HAVE_SETLINEBUF
943 			setlinebuf(stdout);
944 #else
945 			setvbuf(stdout, NULL, _IOLBF, 0);
946 #endif
947 #endif /* WIN32 */
948 			break;
949 
950 		case 'K':
951 			++Kflag;
952 			break;
953 
954 		case 'm':
955 #ifdef LIBSMI
956 			if (smiLoadModule(optarg) == 0) {
957 				error("could not load MIB module %s", optarg);
958 			}
959 			sflag = 1;
960 #else
961 			(void)fprintf(stderr, "%s: ignoring option `-m %s' ",
962 				      program_name, optarg);
963 			(void)fprintf(stderr, "(no libsmi support)\n");
964 #endif
965 			break;
966 
967 		case 'M':
968 			/* TCP-MD5 shared secret */
969 #ifndef HAVE_LIBCRYPTO
970 			warning("crypto code not compiled in");
971 #endif
972 			sigsecret = optarg;
973 			break;
974 
975 		case 'n':
976 			++nflag;
977 			break;
978 
979 		case 'N':
980 			++Nflag;
981 			break;
982 
983 		case 'O':
984 			Oflag = 0;
985 			break;
986 
987 		case 'p':
988 			++pflag;
989 			break;
990 #ifdef HAVE_PCAP_SETDIRECTION
991 		case 'P':
992 			if (strcasecmp(optarg, "in") == 0)
993 				Pflag = PCAP_D_IN;
994 			else if (strcasecmp(optarg, "out") == 0)
995 				Pflag = PCAP_D_OUT;
996 			else if (strcasecmp(optarg, "inout") == 0)
997 				Pflag = PCAP_D_INOUT;
998 			else
999 				error("unknown capture direction `%s'", optarg);
1000 			break;
1001 #endif /* HAVE_PCAP_SETDIRECTION */
1002 		case 'q':
1003 			++qflag;
1004 			++suppress_default_print;
1005 			break;
1006 
1007 		case 'r':
1008 			RFileName = optarg;
1009 			break;
1010 
1011 		case 'R':
1012 			Rflag = 0;
1013 			break;
1014 
1015 		case 's':
1016 			snaplen = strtol(optarg, &end, 0);
1017 			if (optarg == end || *end != '\0'
1018 			    || snaplen < 0 || snaplen > MAXIMUM_SNAPLEN)
1019 				error("invalid snaplen %s", optarg);
1020 			else if (snaplen == 0)
1021 				snaplen = MAXIMUM_SNAPLEN;
1022 			break;
1023 
1024 		case 'S':
1025 			++Sflag;
1026 			break;
1027 
1028 		case 't':
1029 			++tflag;
1030 			break;
1031 
1032 		case 'T':
1033 			if (strcasecmp(optarg, "vat") == 0)
1034 				packettype = PT_VAT;
1035 			else if (strcasecmp(optarg, "wb") == 0)
1036 				packettype = PT_WB;
1037 			else if (strcasecmp(optarg, "rpc") == 0)
1038 				packettype = PT_RPC;
1039 			else if (strcasecmp(optarg, "rtp") == 0)
1040 				packettype = PT_RTP;
1041 			else if (strcasecmp(optarg, "rtcp") == 0)
1042 				packettype = PT_RTCP;
1043 			else if (strcasecmp(optarg, "snmp") == 0)
1044 				packettype = PT_SNMP;
1045 			else if (strcasecmp(optarg, "cnfp") == 0)
1046 				packettype = PT_CNFP;
1047 			else if (strcasecmp(optarg, "tftp") == 0)
1048 				packettype = PT_TFTP;
1049 			else if (strcasecmp(optarg, "aodv") == 0)
1050 				packettype = PT_AODV;
1051 			else if (strcasecmp(optarg, "carp") == 0)
1052 				packettype = PT_CARP;
1053 			else if (strcasecmp(optarg, "radius") == 0)
1054 				packettype = PT_RADIUS;
1055 			else if (strcasecmp(optarg, "zmtp1") == 0)
1056 				packettype = PT_ZMTP1;
1057 			else if (strcasecmp(optarg, "vxlan") == 0)
1058 				packettype = PT_VXLAN;
1059 			else if (strcasecmp(optarg, "pgm") == 0)
1060 				packettype = PT_PGM;
1061 			else if (strcasecmp(optarg, "pgm_zmtp1") == 0)
1062 				packettype = PT_PGM_ZMTP1;
1063 			else if (strcasecmp(optarg, "lmp") == 0)
1064 				packettype = PT_LMP;
1065 			else
1066 				error("unknown packet type `%s'", optarg);
1067 			break;
1068 
1069 		case 'u':
1070 			++uflag;
1071 			break;
1072 
1073 #ifdef HAVE_PCAP_DUMP_FLUSH
1074 		case 'U':
1075 			++Uflag;
1076 			break;
1077 #endif
1078 
1079 		case 'v':
1080 			++vflag;
1081 			break;
1082 
1083 		case 'V':
1084 			VFileName = optarg;
1085 			break;
1086 
1087 		case 'w':
1088 			WFileName = optarg;
1089 			break;
1090 
1091 		case 'W':
1092 			Wflag = atoi(optarg);
1093 			if (Wflag < 0)
1094 				error("invalid number of output files %s", optarg);
1095 			WflagChars = getWflagChars(Wflag);
1096 			break;
1097 
1098 		case 'x':
1099 			++xflag;
1100 			++suppress_default_print;
1101 			break;
1102 
1103 		case 'X':
1104 			++Xflag;
1105 			++suppress_default_print;
1106 			break;
1107 
1108 		case 'y':
1109 			gndo->ndo_dltname = optarg;
1110 			gndo->ndo_dlt =
1111 			  pcap_datalink_name_to_val(gndo->ndo_dltname);
1112 			if (gndo->ndo_dlt < 0)
1113 				error("invalid data link type %s", gndo->ndo_dltname);
1114 			break;
1115 
1116 #if defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG)
1117 		case 'Y':
1118 			{
1119 			/* Undocumented flag */
1120 #ifdef HAVE_PCAP_DEBUG
1121 			extern int pcap_debug;
1122 			pcap_debug = 1;
1123 #else
1124 			extern int yydebug;
1125 			yydebug = 1;
1126 #endif
1127 			}
1128 			break;
1129 #endif
1130 		case 'z':
1131 			if (optarg) {
1132 				zflag = strdup(optarg);
1133 			} else {
1134 				usage();
1135 				/* NOTREACHED */
1136 			}
1137 			break;
1138 
1139 		case 'Z':
1140 			if (optarg) {
1141 				username = strdup(optarg);
1142 			}
1143 			else {
1144 				usage();
1145 				/* NOTREACHED */
1146 			}
1147 			break;
1148 
1149 		default:
1150 			usage();
1151 			/* NOTREACHED */
1152 		}
1153 
1154 	switch (tflag) {
1155 
1156 	case 0: /* Default */
1157 	case 4: /* Default + Date*/
1158 		thiszone = gmt2local(0);
1159 		break;
1160 
1161 	case 1: /* No time stamp */
1162 	case 2: /* Unix timeval style */
1163 	case 3: /* Microseconds since previous packet */
1164         case 5: /* Microseconds since first packet */
1165 		break;
1166 
1167 	default: /* Not supported */
1168 		error("only -t, -tt, -ttt, -tttt and -ttttt are supported");
1169 		break;
1170 	}
1171 
1172 	if (fflag != 0 && (VFileName != NULL || RFileName != NULL))
1173 		error("-f can not be used with -V or -r");
1174 
1175 	if (VFileName != NULL && RFileName != NULL)
1176 		error("-V and -r are mutually exclusive.");
1177 
1178 #ifdef WITH_CHROOT
1179 	/* if run as root, prepare for chrooting */
1180 	if (getuid() == 0 || geteuid() == 0) {
1181 		/* future extensibility for cmd-line arguments */
1182 		if (!chroot_dir)
1183 			chroot_dir = WITH_CHROOT;
1184 	}
1185 #endif
1186 
1187 #ifdef WITH_USER
1188 	/* if run as root, prepare for dropping root privileges */
1189 	if (getuid() == 0 || geteuid() == 0) {
1190 		/* Run with '-Z root' to restore old behaviour */
1191 		if (!username)
1192 			username = WITH_USER;
1193 	}
1194 #endif
1195 
1196 	if (RFileName != NULL || VFileName != NULL) {
1197 		/*
1198 		 * If RFileName is non-null, it's the pathname of a
1199 		 * savefile to read.  If VFileName is non-null, it's
1200 		 * the pathname of a file containing a list of pathnames
1201 		 * (one per line) of savefiles to read.
1202 		 *
1203 		 * In either case, we're reading a savefile, not doing
1204 		 * a live capture.
1205 		 */
1206 #ifndef WIN32
1207 		/*
1208 		 * We don't need network access, so relinquish any set-UID
1209 		 * or set-GID privileges we have (if any).
1210 		 *
1211 		 * We do *not* want set-UID privileges when opening a
1212 		 * trace file, as that might let the user read other
1213 		 * people's trace files (especially if we're set-UID
1214 		 * root).
1215 		 */
1216 		if (setgid(getgid()) != 0 || setuid(getuid()) != 0 )
1217 			fprintf(stderr, "Warning: setgid/setuid failed !\n");
1218 #endif /* WIN32 */
1219 		if (VFileName != NULL) {
1220 			if (VFileName[0] == '-' && VFileName[1] == '\0')
1221 				VFile = stdin;
1222 			else
1223 				VFile = fopen(VFileName, "r");
1224 
1225 			if (VFile == NULL)
1226 				error("Unable to open file: %s\n", strerror(errno));
1227 
1228 			ret = get_next_file(VFile, VFileLine);
1229 			if (!ret)
1230 				error("Nothing in %s\n", VFileName);
1231 			RFileName = VFileLine;
1232 		}
1233 
1234 		pd = pcap_open_offline(RFileName, ebuf);
1235 		if (pd == NULL)
1236 			error("%s", ebuf);
1237 		dlt = pcap_datalink(pd);
1238 		dlt_name = pcap_datalink_val_to_name(dlt);
1239 		if (dlt_name == NULL) {
1240 			fprintf(stderr, "reading from file %s, link-type %u\n",
1241 			    RFileName, dlt);
1242 		} else {
1243 			fprintf(stderr,
1244 			    "reading from file %s, link-type %s (%s)\n",
1245 			    RFileName, dlt_name,
1246 			    pcap_datalink_val_to_description(dlt));
1247 		}
1248 		localnet = 0;
1249 		netmask = 0;
1250 	} else {
1251 		/*
1252 		 * We're doing a live capture.
1253 		 */
1254 		if (device == NULL) {
1255 			device = pcap_lookupdev(ebuf);
1256 			if (device == NULL)
1257 				error("%s", ebuf);
1258 		}
1259 #ifdef WIN32
1260 		/*
1261 		 * Print a message to the standard error on Windows.
1262 		 * XXX - why do it here, with a different message?
1263 		 */
1264 		if(strlen(device) == 1)	/* we assume that an ASCII string is always longer than 1 char */
1265 		{						/* a Unicode string has a \0 as second byte (so strlen() is 1) */
1266 			fprintf(stderr, "%s: listening on %ws\n", program_name, device);
1267 		}
1268 		else
1269 		{
1270 			fprintf(stderr, "%s: listening on %s\n", program_name, device);
1271 		}
1272 
1273 		fflush(stderr);
1274 #endif /* WIN32 */
1275 #ifdef HAVE_PCAP_CREATE
1276 		pd = pcap_create(device, ebuf);
1277 		if (pd == NULL)
1278 			error("%s", ebuf);
1279 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
1280 		if (Jflag)
1281 			show_tstamp_types_and_exit(device, pd);
1282 #endif
1283 		/*
1284 		 * Is this an interface that supports monitor mode?
1285 		 */
1286 		if (pcap_can_set_rfmon(pd) == 1)
1287 			supports_monitor_mode = 1;
1288 		else
1289 			supports_monitor_mode = 0;
1290 		status = pcap_set_snaplen(pd, snaplen);
1291 		if (status != 0)
1292 			error("%s: Can't set snapshot length: %s",
1293 			    device, pcap_statustostr(status));
1294 		status = pcap_set_promisc(pd, !pflag);
1295 		if (status != 0)
1296 			error("%s: Can't set promiscuous mode: %s",
1297 			    device, pcap_statustostr(status));
1298 		if (Iflag) {
1299 			status = pcap_set_rfmon(pd, 1);
1300 			if (status != 0)
1301 				error("%s: Can't set monitor mode: %s",
1302 				    device, pcap_statustostr(status));
1303 		}
1304 		status = pcap_set_timeout(pd, 1000);
1305 		if (status != 0)
1306 			error("%s: pcap_set_timeout failed: %s",
1307 			    device, pcap_statustostr(status));
1308 		if (Bflag != 0) {
1309 			status = pcap_set_buffer_size(pd, Bflag);
1310 			if (status != 0)
1311 				error("%s: Can't set buffer size: %s",
1312 				    device, pcap_statustostr(status));
1313 		}
1314 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
1315                 if (jflag != -1) {
1316 			status = pcap_set_tstamp_type(pd, jflag);
1317 			if (status < 0)
1318 				error("%s: Can't set time stamp type: %s",
1319 			    	    device, pcap_statustostr(status));
1320 		}
1321 #endif
1322 		status = pcap_activate(pd);
1323 		if (status < 0) {
1324 			/*
1325 			 * pcap_activate() failed.
1326 			 */
1327 			cp = pcap_geterr(pd);
1328 			if (status == PCAP_ERROR)
1329 				error("%s", cp);
1330 			else if ((status == PCAP_ERROR_NO_SUCH_DEVICE ||
1331 			          status == PCAP_ERROR_PERM_DENIED) &&
1332 			         *cp != '\0')
1333 				error("%s: %s\n(%s)", device,
1334 				    pcap_statustostr(status), cp);
1335 			else
1336 				error("%s: %s", device,
1337 				    pcap_statustostr(status));
1338 		} else if (status > 0) {
1339 			/*
1340 			 * pcap_activate() succeeded, but it's warning us
1341 			 * of a problem it had.
1342 			 */
1343 			cp = pcap_geterr(pd);
1344 			if (status == PCAP_WARNING)
1345 				warning("%s", cp);
1346 			else if (status == PCAP_WARNING_PROMISC_NOTSUP &&
1347 			         *cp != '\0')
1348 				warning("%s: %s\n(%s)", device,
1349 				    pcap_statustostr(status), cp);
1350 			else
1351 				warning("%s: %s", device,
1352 				    pcap_statustostr(status));
1353 		}
1354 #ifdef HAVE_PCAP_SETDIRECTION
1355 		if (Pflag != -1) {
1356 			status = pcap_setdirection(pd, Pflag);
1357 			if (status != 0)
1358 				error("%s: pcap_setdirection() failed: %s",
1359 				      device,  pcap_geterr(pd));
1360 		}
1361 #endif
1362 #else
1363 		*ebuf = '\0';
1364 		pd = pcap_open_live(device, snaplen, !pflag, 1000, ebuf);
1365 		if (pd == NULL)
1366 			error("%s", ebuf);
1367 		else if (*ebuf)
1368 			warning("%s", ebuf);
1369 #endif /* HAVE_PCAP_CREATE */
1370 		/*
1371 		 * Let user own process after socket has been opened.
1372 		 */
1373 #ifndef WIN32
1374 		if (setgid(getgid()) != 0 || setuid(getuid()) != 0)
1375 			fprintf(stderr, "Warning: setgid/setuid failed !\n");
1376 #endif /* WIN32 */
1377 #if !defined(HAVE_PCAP_CREATE) && defined(WIN32)
1378 		if(Bflag != 0)
1379 			if(pcap_setbuff(pd, Bflag)==-1){
1380 				error("%s", pcap_geterr(pd));
1381 			}
1382 #endif /* !defined(HAVE_PCAP_CREATE) && defined(WIN32) */
1383 		if (Lflag)
1384 			show_dlts_and_exit(device, pd);
1385 		if (gndo->ndo_dlt >= 0) {
1386 #ifdef HAVE_PCAP_SET_DATALINK
1387 			if (pcap_set_datalink(pd, gndo->ndo_dlt) < 0)
1388 				error("%s", pcap_geterr(pd));
1389 #else
1390 			/*
1391 			 * We don't actually support changing the
1392 			 * data link type, so we only let them
1393 			 * set it to what it already is.
1394 			 */
1395 			if (gndo->ndo_dlt != pcap_datalink(pd)) {
1396 				error("%s is not one of the DLTs supported by this device\n",
1397 				      gndo->ndo_dltname);
1398 			}
1399 #endif
1400 			(void)fprintf(stderr, "%s: data link type %s\n",
1401 				      program_name, gndo->ndo_dltname);
1402 			(void)fflush(stderr);
1403 		}
1404 		i = pcap_snapshot(pd);
1405 		if (snaplen < i) {
1406 			warning("snaplen raised from %d to %d", snaplen, i);
1407 			snaplen = i;
1408 		}
1409 		if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
1410 			localnet = 0;
1411 			netmask = 0;
1412 			warning("%s", ebuf);
1413 		}
1414 	}
1415 	if (infile)
1416 		cmdbuf = read_infile(infile);
1417 	else
1418 		cmdbuf = copy_argv(&argv[optind]);
1419 
1420 	if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
1421 		error("%s", pcap_geterr(pd));
1422 	if (dflag) {
1423 		bpf_dump(&fcode, dflag);
1424 		pcap_close(pd);
1425 		free(cmdbuf);
1426 		exit(0);
1427 	}
1428 	init_addrtoname(localnet, netmask);
1429         init_checksum();
1430 
1431 #ifndef WIN32
1432 	(void)setsignal(SIGPIPE, cleanup);
1433 	(void)setsignal(SIGTERM, cleanup);
1434 	(void)setsignal(SIGINT, cleanup);
1435 #endif /* WIN32 */
1436 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
1437 	(void)setsignal(SIGCHLD, child_cleanup);
1438 #endif
1439 	/* Cooperate with nohup(1) */
1440 #ifndef WIN32
1441 	if ((oldhandler = setsignal(SIGHUP, cleanup)) != SIG_DFL)
1442 		(void)setsignal(SIGHUP, oldhandler);
1443 #endif /* WIN32 */
1444 
1445 #ifndef WIN32
1446 	/*
1447 	 * If a user name was specified with "-Z", attempt to switch to
1448 	 * that user's UID.  This would probably be used with sudo,
1449 	 * to allow tcpdump to be run in a special restricted
1450 	 * account (if you just want to allow users to open capture
1451 	 * devices, and can't just give users that permission,
1452 	 * you'd make tcpdump set-UID or set-GID).
1453 	 *
1454 	 * Tcpdump doesn't necessarily write only to one savefile;
1455 	 * the general only way to allow a -Z instance to write to
1456 	 * savefiles as the user under whose UID it's run, rather
1457 	 * than as the user specified with -Z, would thus be to switch
1458 	 * to the original user ID before opening a capture file and
1459 	 * then switch back to the -Z user ID after opening the savefile.
1460 	 * Switching to the -Z user ID only after opening the first
1461 	 * savefile doesn't handle the general case.
1462 	 */
1463 
1464 #ifdef HAVE_CAP_NG_H
1465 	/* We are running as root and we will be writing to savefile */
1466 	if ((getuid() == 0 || geteuid() == 0) && WFileName) {
1467 		if (username) {
1468 			/* Drop all capabilities from effective set */
1469 			capng_clear(CAPNG_EFFECTIVE);
1470 			/* Add capabilities we will need*/
1471 			capng_update(CAPNG_ADD, CAPNG_PERMITTED, CAP_SETUID);
1472 			capng_update(CAPNG_ADD, CAPNG_PERMITTED, CAP_SETGID);
1473 			capng_update(CAPNG_ADD, CAPNG_PERMITTED, CAP_DAC_OVERRIDE);
1474 
1475 			capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_SETUID);
1476 			capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_SETGID);
1477 			capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
1478 
1479 			capng_apply(CAPNG_SELECT_BOTH);
1480 		}
1481 	}
1482 #endif /* HAVE_CAP_NG_H */
1483 
1484 	if (getuid() == 0 || geteuid() == 0) {
1485 		if (username || chroot_dir) {
1486 #ifndef HAVE_CAP_NG_H
1487 			if (!WFileName)
1488 #endif
1489 			droproot(username, chroot_dir);
1490 		}
1491 
1492 	}
1493 #endif /* WIN32 */
1494 
1495 	if (pcap_setfilter(pd, &fcode) < 0)
1496 		error("%s", pcap_geterr(pd));
1497 	if (WFileName) {
1498 		pcap_dumper_t *p;
1499 		/* Do not exceed the default PATH_MAX for files. */
1500 		dumpinfo.CurrentFileName = (char *)malloc(PATH_MAX + 1);
1501 
1502 		if (dumpinfo.CurrentFileName == NULL)
1503 			error("malloc of dumpinfo.CurrentFileName");
1504 
1505 		/* We do not need numbering for dumpfiles if Cflag isn't set. */
1506 		if (Cflag != 0)
1507 		  MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, WflagChars);
1508 		else
1509 		  MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, 0);
1510 
1511 		p = pcap_dump_open(pd, dumpinfo.CurrentFileName);
1512 #ifdef HAVE_CAP_NG_H
1513         /* Give up capabilities, clear Effective set */
1514         capng_clear(CAPNG_EFFECTIVE);
1515 #endif
1516 		if (p == NULL)
1517 			error("%s", pcap_geterr(pd));
1518 		if (Cflag != 0 || Gflag != 0) {
1519 			callback = dump_packet_and_trunc;
1520 			dumpinfo.WFileName = WFileName;
1521 			dumpinfo.pd = pd;
1522 			dumpinfo.p = p;
1523 			pcap_userdata = (u_char *)&dumpinfo;
1524 		} else {
1525 			callback = dump_packet;
1526 			pcap_userdata = (u_char *)p;
1527 		}
1528 #ifdef HAVE_PCAP_DUMP_FLUSH
1529 		if (Uflag)
1530 			pcap_dump_flush(p);
1531 #endif
1532 	} else {
1533 		type = pcap_datalink(pd);
1534 		printinfo = get_print_info(type);
1535 		callback = print_packet;
1536 		pcap_userdata = (u_char *)&printinfo;
1537 	}
1538 
1539 #ifdef SIGNAL_REQ_INFO
1540 	/*
1541 	 * We can't get statistics when reading from a file rather
1542 	 * than capturing from a device.
1543 	 */
1544 	if (RFileName == NULL)
1545 		(void)setsignal(SIGNAL_REQ_INFO, requestinfo);
1546 #endif
1547 
1548 	if (vflag > 0 && WFileName) {
1549 		/*
1550 		 * When capturing to a file, "-v" means tcpdump should,
1551 		 * every 10 secodns, "v"erbosely report the number of
1552 		 * packets captured.
1553 		 */
1554 #ifdef USE_WIN32_MM_TIMER
1555 		/* call verbose_stats_dump() each 1000 +/-100msec */
1556 		timer_id = timeSetEvent(1000, 100, verbose_stats_dump, 0, TIME_PERIODIC);
1557 		setvbuf(stderr, NULL, _IONBF, 0);
1558 #elif defined(HAVE_ALARM)
1559 		(void)setsignal(SIGALRM, verbose_stats_dump);
1560 		alarm(1);
1561 #endif
1562 	}
1563 
1564 #ifndef WIN32
1565 	if (RFileName == NULL) {
1566 		/*
1567 		 * Live capture (if -V was specified, we set RFileName
1568 		 * to a file from the -V file).  Print a message to
1569 		 * the standard error on UN*X.
1570 		 */
1571 		if (!vflag && !WFileName) {
1572 			(void)fprintf(stderr,
1573 			    "%s: verbose output suppressed, use -v or -vv for full protocol decode\n",
1574 			    program_name);
1575 		} else
1576 			(void)fprintf(stderr, "%s: ", program_name);
1577 		dlt = pcap_datalink(pd);
1578 		dlt_name = pcap_datalink_val_to_name(dlt);
1579 		if (dlt_name == NULL) {
1580 			(void)fprintf(stderr, "listening on %s, link-type %u, capture size %u bytes\n",
1581 			    device, dlt, snaplen);
1582 		} else {
1583 			(void)fprintf(stderr, "listening on %s, link-type %s (%s), capture size %u bytes\n",
1584 			    device, dlt_name,
1585 			    pcap_datalink_val_to_description(dlt), snaplen);
1586 		}
1587 		(void)fflush(stderr);
1588 	}
1589 
1590 	/*
1591 	 * If a user name was specified with "-Z", attempt to switch to
1592 	 * that user's UID.  This would probably be used with sudo,
1593 	 * to allow tcpdump to be run in a special restricted
1594 	 * account (if you just want to allow users to open capture
1595 	 * devices, and can't just give users that permission,
1596 	 * you'd make tcpdump set-UID or set-GID).
1597 	 *
1598 	 * Tcpdump doesn't necessarily write only to one savefile;
1599 	 * the general only way to allow a -Z instance to write to
1600 	 * savefiles as the user under whose UID it's run, rather
1601 	 * than as the user specified with -Z, would thus be to switch
1602 	 * to the original user ID before opening a capture file and
1603 	 * then switch back to the -Z user ID after opening the savefile.
1604 	 * Switching to the -Z user ID only after opening the first
1605 	 * savefile doesn't handle the general case.
1606 	 */
1607 	if (getuid() == 0 || geteuid() == 0) {
1608 		if (username || chroot_dir)
1609 			droproot(username, chroot_dir);
1610 	}
1611 #endif /* WIN32 */
1612 	do {
1613 		status = pcap_loop(pd, cnt, callback, pcap_userdata);
1614 		if (WFileName == NULL) {
1615 			/*
1616 			 * We're printing packets.  Flush the printed output,
1617 			 * so it doesn't get intermingled with error output.
1618 			 */
1619 			if (status == -2) {
1620 				/*
1621 				 * We got interrupted, so perhaps we didn't
1622 				 * manage to finish a line we were printing.
1623 				 * Print an extra newline, just in case.
1624 				 */
1625 				putchar('\n');
1626 			}
1627 			(void)fflush(stdout);
1628 		}
1629                 if (status == -2) {
1630 			/*
1631 			 * We got interrupted. If we are reading multiple
1632 			 * files (via -V) set these so that we stop.
1633 			 */
1634 			VFileName = NULL;
1635 			ret = NULL;
1636 		}
1637 		if (status == -1) {
1638 			/*
1639 			 * Error.  Report it.
1640 			 */
1641 			(void)fprintf(stderr, "%s: pcap_loop: %s\n",
1642 			    program_name, pcap_geterr(pd));
1643 		}
1644 		if (RFileName == NULL) {
1645 			/*
1646 			 * We're doing a live capture.  Report the capture
1647 			 * statistics.
1648 			 */
1649 			info(1);
1650 		}
1651 		pcap_close(pd);
1652 		if (VFileName != NULL) {
1653 			ret = get_next_file(VFile, VFileLine);
1654 			if (ret) {
1655 				RFileName = VFileLine;
1656 				pd = pcap_open_offline(RFileName, ebuf);
1657 				if (pd == NULL)
1658 					error("%s", ebuf);
1659 				new_dlt = pcap_datalink(pd);
1660 				if (WFileName && new_dlt != dlt)
1661 					error("%s: new dlt does not match original", RFileName);
1662 				printinfo = get_print_info(new_dlt);
1663 				dlt_name = pcap_datalink_val_to_name(new_dlt);
1664 				if (dlt_name == NULL) {
1665 					fprintf(stderr, "reading from file %s, link-type %u\n",
1666 					RFileName, new_dlt);
1667 				} else {
1668 					fprintf(stderr,
1669 					"reading from file %s, link-type %s (%s)\n",
1670 					RFileName, dlt_name,
1671 					pcap_datalink_val_to_description(new_dlt));
1672 				}
1673 				if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
1674 					error("%s", pcap_geterr(pd));
1675 				if (pcap_setfilter(pd, &fcode) < 0)
1676 					error("%s", pcap_geterr(pd));
1677 			}
1678 		}
1679 	}
1680 	while (ret != NULL);
1681 
1682 	free(cmdbuf);
1683 	exit(status == -1 ? 1 : 0);
1684 }
1685 
1686 /* make a clean exit on interrupts */
1687 static RETSIGTYPE
1688 cleanup(int signo _U_)
1689 {
1690 #ifdef USE_WIN32_MM_TIMER
1691 	if (timer_id)
1692 		timeKillEvent(timer_id);
1693 	timer_id = 0;
1694 #elif defined(HAVE_ALARM)
1695 	alarm(0);
1696 #endif
1697 
1698 #ifdef HAVE_PCAP_BREAKLOOP
1699 	/*
1700 	 * We have "pcap_breakloop()"; use it, so that we do as little
1701 	 * as possible in the signal handler (it's probably not safe
1702 	 * to do anything with standard I/O streams in a signal handler -
1703 	 * the ANSI C standard doesn't say it is).
1704 	 */
1705 	pcap_breakloop(pd);
1706 #else
1707 	/*
1708 	 * We don't have "pcap_breakloop()"; this isn't safe, but
1709 	 * it's the best we can do.  Print the summary if we're
1710 	 * not reading from a savefile - i.e., if we're doing a
1711 	 * live capture - and exit.
1712 	 */
1713 	if (pd != NULL && pcap_file(pd) == NULL) {
1714 		/*
1715 		 * We got interrupted, so perhaps we didn't
1716 		 * manage to finish a line we were printing.
1717 		 * Print an extra newline, just in case.
1718 		 */
1719 		putchar('\n');
1720 		(void)fflush(stdout);
1721 		info(1);
1722 	}
1723 	exit(0);
1724 #endif
1725 }
1726 
1727 /*
1728   On windows, we do not use a fork, so we do not care less about
1729   waiting a child processes to die
1730  */
1731 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
1732 static RETSIGTYPE
1733 child_cleanup(int signo _U_)
1734 {
1735   wait(NULL);
1736 }
1737 #endif /* HAVE_FORK && HAVE_VFORK */
1738 
1739 static void
1740 info(register int verbose)
1741 {
1742 	struct pcap_stat stat;
1743 
1744 	/*
1745 	 * Older versions of libpcap didn't set ps_ifdrop on some
1746 	 * platforms; initialize it to 0 to handle that.
1747 	 */
1748 	stat.ps_ifdrop = 0;
1749 	if (pcap_stats(pd, &stat) < 0) {
1750 		(void)fprintf(stderr, "pcap_stats: %s\n", pcap_geterr(pd));
1751 		infoprint = 0;
1752 		return;
1753 	}
1754 
1755 	if (!verbose)
1756 		fprintf(stderr, "%s: ", program_name);
1757 
1758 	(void)fprintf(stderr, "%u packet%s captured", packets_captured,
1759 	    PLURAL_SUFFIX(packets_captured));
1760 	if (!verbose)
1761 		fputs(", ", stderr);
1762 	else
1763 		putc('\n', stderr);
1764 	(void)fprintf(stderr, "%u packet%s received by filter", stat.ps_recv,
1765 	    PLURAL_SUFFIX(stat.ps_recv));
1766 	if (!verbose)
1767 		fputs(", ", stderr);
1768 	else
1769 		putc('\n', stderr);
1770 	(void)fprintf(stderr, "%u packet%s dropped by kernel", stat.ps_drop,
1771 	    PLURAL_SUFFIX(stat.ps_drop));
1772 	if (stat.ps_ifdrop != 0) {
1773 		if (!verbose)
1774 			fputs(", ", stderr);
1775 		else
1776 			putc('\n', stderr);
1777 		(void)fprintf(stderr, "%u packet%s dropped by interface\n",
1778 		    stat.ps_ifdrop, PLURAL_SUFFIX(stat.ps_ifdrop));
1779 	} else
1780 		putc('\n', stderr);
1781 	infoprint = 0;
1782 }
1783 
1784 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
1785 static void
1786 compress_savefile(const char *filename)
1787 {
1788 # ifdef HAVE_FORK
1789 	if (fork())
1790 # else
1791 	if (vfork())
1792 # endif
1793 		return;
1794 	/*
1795 	 * Set to lowest priority so that this doesn't disturb the capture
1796 	 */
1797 #ifdef NZERO
1798 	setpriority(PRIO_PROCESS, 0, NZERO - 1);
1799 #else
1800 	setpriority(PRIO_PROCESS, 0, 19);
1801 #endif
1802 	if (execlp(zflag, zflag, filename, (char *)NULL) == -1)
1803 		fprintf(stderr,
1804 			"compress_savefile:execlp(%s, %s): %s\n",
1805 			zflag,
1806 			filename,
1807 			strerror(errno));
1808 # ifdef HAVE_FORK
1809 	exit(1);
1810 # else
1811 	_exit(1);
1812 # endif
1813 }
1814 #else  /* HAVE_FORK && HAVE_VFORK */
1815 static void
1816 compress_savefile(const char *filename)
1817 {
1818 	fprintf(stderr,
1819 		"compress_savefile failed. Functionality not implemented under your system\n");
1820 }
1821 #endif /* HAVE_FORK && HAVE_VFORK */
1822 
1823 static void
1824 dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1825 {
1826 	struct dump_info *dump_info;
1827 
1828 	++packets_captured;
1829 
1830 	++infodelay;
1831 
1832 	dump_info = (struct dump_info *)user;
1833 
1834 	/*
1835 	 * XXX - this won't force the file to rotate on the specified time
1836 	 * boundary, but it will rotate on the first packet received after the
1837 	 * specified Gflag number of seconds. Note: if a Gflag time boundary
1838 	 * and a Cflag size boundary coincide, the time rotation will occur
1839 	 * first thereby cancelling the Cflag boundary (since the file should
1840 	 * be 0).
1841 	 */
1842 	if (Gflag != 0) {
1843 		/* Check if it is time to rotate */
1844 		time_t t;
1845 
1846 		/* Get the current time */
1847 		if ((t = time(NULL)) == (time_t)-1) {
1848 			error("dump_and_trunc_packet: can't get current_time: %s",
1849 			    pcap_strerror(errno));
1850 		}
1851 
1852 
1853 		/* If the time is greater than the specified window, rotate */
1854 		if (t - Gflag_time >= Gflag) {
1855 			/* Update the Gflag_time */
1856 			Gflag_time = t;
1857 			/* Update Gflag_count */
1858 			Gflag_count++;
1859 			/*
1860 			 * Close the current file and open a new one.
1861 			 */
1862 			pcap_dump_close(dump_info->p);
1863 
1864 			/*
1865 			 * Compress the file we just closed, if the user asked for it
1866 			 */
1867 			if (zflag != NULL)
1868 				compress_savefile(dump_info->CurrentFileName);
1869 
1870 			/*
1871 			 * Check to see if we've exceeded the Wflag (when
1872 			 * not using Cflag).
1873 			 */
1874 			if (Cflag == 0 && Wflag > 0 && Gflag_count >= Wflag) {
1875 				(void)fprintf(stderr, "Maximum file limit reached: %d\n",
1876 				    Wflag);
1877 				exit(0);
1878 				/* NOTREACHED */
1879 			}
1880 			if (dump_info->CurrentFileName != NULL)
1881 				free(dump_info->CurrentFileName);
1882 			/* Allocate space for max filename + \0. */
1883 			dump_info->CurrentFileName = (char *)malloc(PATH_MAX + 1);
1884 			if (dump_info->CurrentFileName == NULL)
1885 				error("dump_packet_and_trunc: malloc");
1886 			/*
1887 			 * This is always the first file in the Cflag
1888 			 * rotation: e.g. 0
1889 			 * We also don't need numbering if Cflag is not set.
1890 			 */
1891 			if (Cflag != 0)
1892 				MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0,
1893 				    WflagChars);
1894 			else
1895 				MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0, 0);
1896 
1897 #ifdef HAVE_CAP_NG_H
1898 			capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
1899 			capng_apply(CAPNG_EFFECTIVE);
1900 #endif /* HAVE_CAP_NG_H */
1901 			dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
1902 #ifdef HAVE_CAP_NG_H
1903 			capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
1904 			capng_apply(CAPNG_EFFECTIVE);
1905 #endif /* HAVE_CAP_NG_H */
1906 			if (dump_info->p == NULL)
1907 				error("%s", pcap_geterr(pd));
1908 		}
1909 	}
1910 
1911 	/*
1912 	 * XXX - this won't prevent capture files from getting
1913 	 * larger than Cflag - the last packet written to the
1914 	 * file could put it over Cflag.
1915 	 */
1916 	if (Cflag != 0 && pcap_dump_ftell(dump_info->p) > Cflag) {
1917 		/*
1918 		 * Close the current file and open a new one.
1919 		 */
1920 		pcap_dump_close(dump_info->p);
1921 
1922 		/*
1923 		 * Compress the file we just closed, if the user asked for it
1924 		 */
1925 		if (zflag != NULL)
1926 			compress_savefile(dump_info->CurrentFileName);
1927 
1928 		Cflag_count++;
1929 		if (Wflag > 0) {
1930 			if (Cflag_count >= Wflag)
1931 				Cflag_count = 0;
1932 		}
1933 		if (dump_info->CurrentFileName != NULL)
1934 			free(dump_info->CurrentFileName);
1935 		dump_info->CurrentFileName = (char *)malloc(PATH_MAX + 1);
1936 		if (dump_info->CurrentFileName == NULL)
1937 			error("dump_packet_and_trunc: malloc");
1938 		MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, Cflag_count, WflagChars);
1939 		dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
1940 		if (dump_info->p == NULL)
1941 			error("%s", pcap_geterr(pd));
1942 	}
1943 
1944 	pcap_dump((u_char *)dump_info->p, h, sp);
1945 #ifdef HAVE_PCAP_DUMP_FLUSH
1946 	if (Uflag)
1947 		pcap_dump_flush(dump_info->p);
1948 #endif
1949 
1950 	--infodelay;
1951 	if (infoprint)
1952 		info(0);
1953 }
1954 
1955 static void
1956 dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1957 {
1958 	++packets_captured;
1959 
1960 	++infodelay;
1961 
1962 	pcap_dump(user, h, sp);
1963 #ifdef HAVE_PCAP_DUMP_FLUSH
1964 	if (Uflag)
1965 		pcap_dump_flush((pcap_dumper_t *)user);
1966 #endif
1967 
1968 	--infodelay;
1969 	if (infoprint)
1970 		info(0);
1971 }
1972 
1973 static void
1974 print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1975 {
1976 	struct print_info *print_info;
1977 	u_int hdrlen;
1978 
1979 	++packets_captured;
1980 
1981 	++infodelay;
1982 	ts_print(&h->ts);
1983 
1984 	print_info = (struct print_info *)user;
1985 
1986 	/*
1987 	 * Some printers want to check that they're not walking off the
1988 	 * end of the packet.
1989 	 * Rather than pass it all the way down, we set this global.
1990 	 */
1991 	snapend = sp + h->caplen;
1992 
1993         if(print_info->ndo_type) {
1994                 hdrlen = (*print_info->p.ndo_printer)(print_info->ndo, h, sp);
1995         } else {
1996                 hdrlen = (*print_info->p.printer)(h, sp);
1997         }
1998 
1999 	if (Xflag) {
2000 		/*
2001 		 * Print the raw packet data in hex and ASCII.
2002 		 */
2003 		if (Xflag > 1) {
2004 			/*
2005 			 * Include the link-layer header.
2006 			 */
2007 			hex_and_ascii_print("\n\t", sp, h->caplen);
2008 		} else {
2009 			/*
2010 			 * Don't include the link-layer header - and if
2011 			 * we have nothing past the link-layer header,
2012 			 * print nothing.
2013 			 */
2014 			if (h->caplen > hdrlen)
2015 				hex_and_ascii_print("\n\t", sp + hdrlen,
2016 				    h->caplen - hdrlen);
2017 		}
2018 	} else if (xflag) {
2019 		/*
2020 		 * Print the raw packet data in hex.
2021 		 */
2022 		if (xflag > 1) {
2023 			/*
2024 			 * Include the link-layer header.
2025 			 */
2026 			hex_print("\n\t", sp, h->caplen);
2027 		} else {
2028 			/*
2029 			 * Don't include the link-layer header - and if
2030 			 * we have nothing past the link-layer header,
2031 			 * print nothing.
2032 			 */
2033 			if (h->caplen > hdrlen)
2034 				hex_print("\n\t", sp + hdrlen,
2035 				    h->caplen - hdrlen);
2036 		}
2037 	} else if (Aflag) {
2038 		/*
2039 		 * Print the raw packet data in ASCII.
2040 		 */
2041 		if (Aflag > 1) {
2042 			/*
2043 			 * Include the link-layer header.
2044 			 */
2045 			ascii_print(sp, h->caplen);
2046 		} else {
2047 			/*
2048 			 * Don't include the link-layer header - and if
2049 			 * we have nothing past the link-layer header,
2050 			 * print nothing.
2051 			 */
2052 			if (h->caplen > hdrlen)
2053 				ascii_print(sp + hdrlen, h->caplen - hdrlen);
2054 		}
2055 	}
2056 
2057 	putchar('\n');
2058 
2059 	--infodelay;
2060 	if (infoprint)
2061 		info(0);
2062 }
2063 
2064 #ifdef WIN32
2065 	/*
2066 	 * XXX - there should really be libpcap calls to get the version
2067 	 * number as a string (the string would be generated from #defines
2068 	 * at run time, so that it's not generated from string constants
2069 	 * in the library, as, on many UNIX systems, those constants would
2070 	 * be statically linked into the application executable image, and
2071 	 * would thus reflect the version of libpcap on the system on
2072 	 * which the application was *linked*, not the system on which it's
2073 	 * *running*.
2074 	 *
2075 	 * That routine should be documented, unlike the "version[]"
2076 	 * string, so that UNIX vendors providing their own libpcaps
2077 	 * don't omit it (as a couple of vendors have...).
2078 	 *
2079 	 * Packet.dll should perhaps also export a routine to return the
2080 	 * version number of the Packet.dll code, to supply the
2081 	 * "Wpcap_version" information on Windows.
2082 	 */
2083 	char WDversion[]="current-cvs.tcpdump.org";
2084 #if !defined(HAVE_GENERATED_VERSION)
2085 	char version[]="current-cvs.tcpdump.org";
2086 #endif
2087 	char pcap_version[]="current-cvs.tcpdump.org";
2088 	char Wpcap_version[]="3.1";
2089 #endif
2090 
2091 /*
2092  * By default, print the specified data out in hex and ASCII.
2093  */
2094 static void
2095 ndo_default_print(netdissect_options *ndo _U_, const u_char *bp, u_int length)
2096 {
2097 	hex_and_ascii_print("\n\t", bp, length); /* pass on lf and identation string */
2098 }
2099 
2100 void
2101 default_print(const u_char *bp, u_int length)
2102 {
2103 	ndo_default_print(gndo, bp, length);
2104 }
2105 
2106 #ifdef SIGNAL_REQ_INFO
2107 RETSIGTYPE requestinfo(int signo _U_)
2108 {
2109 	if (infodelay)
2110 		++infoprint;
2111 	else
2112 		info(0);
2113 }
2114 #endif
2115 
2116 /*
2117  * Called once each second in verbose mode while dumping to file
2118  */
2119 #ifdef USE_WIN32_MM_TIMER
2120 void CALLBACK verbose_stats_dump (UINT timer_id _U_, UINT msg _U_, DWORD_PTR arg _U_,
2121 				  DWORD_PTR dw1 _U_, DWORD_PTR dw2 _U_)
2122 {
2123 	struct pcap_stat stat;
2124 
2125 	if (infodelay == 0 && pcap_stats(pd, &stat) >= 0)
2126 		fprintf(stderr, "Got %u\r", packets_captured);
2127 }
2128 #elif defined(HAVE_ALARM)
2129 static void verbose_stats_dump(int sig _U_)
2130 {
2131 	struct pcap_stat stat;
2132 
2133 	if (infodelay == 0 && pcap_stats(pd, &stat) >= 0)
2134 		fprintf(stderr, "Got %u\r", packets_captured);
2135 	alarm(1);
2136 }
2137 #endif
2138 
2139 static void
2140 usage(void)
2141 {
2142 	extern char version[];
2143 #ifndef HAVE_PCAP_LIB_VERSION
2144 #if defined(WIN32) || defined(HAVE_PCAP_VERSION)
2145 	extern char pcap_version[];
2146 #else /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
2147 	static char pcap_version[] = "unknown";
2148 #endif /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
2149 #endif /* HAVE_PCAP_LIB_VERSION */
2150 
2151 #ifdef HAVE_PCAP_LIB_VERSION
2152 #ifdef WIN32
2153 	(void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
2154 #else /* WIN32 */
2155 	(void)fprintf(stderr, "%s version %s\n", program_name, version);
2156 #endif /* WIN32 */
2157 	(void)fprintf(stderr, "%s\n",pcap_lib_version());
2158 #else /* HAVE_PCAP_LIB_VERSION */
2159 #ifdef WIN32
2160 	(void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
2161 	(void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version);
2162 #else /* WIN32 */
2163 	(void)fprintf(stderr, "%s version %s\n", program_name, version);
2164 	(void)fprintf(stderr, "libpcap version %s\n", pcap_version);
2165 #endif /* WIN32 */
2166 #endif /* HAVE_PCAP_LIB_VERSION */
2167 	(void)fprintf(stderr,
2168 "Usage: %s [-aAbd" D_FLAG "efhH" I_FLAG J_FLAG "KlLnNOpqRStu" U_FLAG "vxX]" B_FLAG_USAGE " [ -c count ]\n", program_name);
2169 	(void)fprintf(stderr,
2170 "\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n");
2171 	(void)fprintf(stderr,
2172 "\t\t[ -i interface ]" j_FLAG_USAGE " [ -M secret ]\n");
2173 #ifdef HAVE_PCAP_SETDIRECTION
2174 	(void)fprintf(stderr,
2175 "\t\t[ -P in|out|inout ]\n");
2176 #endif
2177 	(void)fprintf(stderr,
2178 "\t\t[ -r file ] [ -s snaplen ] [ -T type ] [ -V file ] [ -w file ]\n");
2179 	(void)fprintf(stderr,
2180 "\t\t[ -W filecount ] [ -y datalinktype ] [ -z command ]\n");
2181 	(void)fprintf(stderr,
2182 "\t\t[ -Z user ] [ expression ]\n");
2183 	exit(1);
2184 }
2185 
2186 
2187 
2188 /* VARARGS */
2189 static void
2190 ndo_error(netdissect_options *ndo _U_, const char *fmt, ...)
2191 {
2192 	va_list ap;
2193 
2194 	(void)fprintf(stderr, "%s: ", program_name);
2195 	va_start(ap, fmt);
2196 	(void)vfprintf(stderr, fmt, ap);
2197 	va_end(ap);
2198 	if (*fmt) {
2199 		fmt += strlen(fmt);
2200 		if (fmt[-1] != '\n')
2201 			(void)fputc('\n', stderr);
2202 	}
2203 	exit(1);
2204 	/* NOTREACHED */
2205 }
2206 
2207 /* VARARGS */
2208 static void
2209 ndo_warning(netdissect_options *ndo _U_, const char *fmt, ...)
2210 {
2211 	va_list ap;
2212 
2213 	(void)fprintf(stderr, "%s: WARNING: ", program_name);
2214 	va_start(ap, fmt);
2215 	(void)vfprintf(stderr, fmt, ap);
2216 	va_end(ap);
2217 	if (*fmt) {
2218 		fmt += strlen(fmt);
2219 		if (fmt[-1] != '\n')
2220 			(void)fputc('\n', stderr);
2221 	}
2222 }
2223