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1 /*
2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that: (1) source code distributions
7  * retain the above copyright notice and this paragraph in its entirety, (2)
8  * distributions including binary code include the above copyright notice and
9  * this paragraph in its entirety in the documentation or other materials
10  * provided with the distribution, and (3) all advertising materials mentioning
11  * features or use of this software display the following acknowledgement:
12  * ``This product includes software developed by the University of California,
13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
14  * the University nor the names of its contributors may be used to endorse
15  * or promote products derived from this software without specific prior
16  * written permission.
17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
20  *
21  * Support for splitting captures into multiple files with a maximum
22  * file size:
23  *
24  * Copyright (c) 2001
25  *	Seth Webster <swebster@sst.ll.mit.edu>
26  */
27 
28 #ifndef lint
29 static const char copyright[] _U_ =
30     "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
31 The Regents of the University of California.  All rights reserved.\n";
32 #endif
33 
34 /*
35  * tcpdump - dump traffic on a network
36  *
37  * First written in 1987 by Van Jacobson, Lawrence Berkeley Laboratory.
38  * Mercilessly hacked and occasionally improved since then via the
39  * combined efforts of Van, Steve McCanne and Craig Leres of LBL.
40  */
41 
42 #ifdef HAVE_CONFIG_H
43 #include "config.h"
44 #endif
45 
46 /*
47  * Mac OS X may ship pcap.h from libpcap 0.6 with a libpcap based on
48  * 0.8.  That means it has pcap_findalldevs() but the header doesn't
49  * define pcap_if_t, meaning that we can't actually *use* pcap_findalldevs().
50  */
51 #ifdef HAVE_PCAP_FINDALLDEVS
52 #ifndef HAVE_PCAP_IF_T
53 #undef HAVE_PCAP_FINDALLDEVS
54 #endif
55 #endif
56 
57 #include <netdissect-stdinc.h>
58 
59 #include <sys/stat.h>
60 
61 #ifdef HAVE_FCNTL_H
62 #include <fcntl.h>
63 #endif
64 
65 #ifdef HAVE_LIBCRYPTO
66 #include <openssl/crypto.h>
67 #endif
68 
69 #ifdef HAVE_GETOPT_LONG
70 #include <getopt.h>
71 #else
72 #include "getopt_long.h"
73 #endif
74 /* Capsicum-specific code requires macros from <net/bpf.h>, which will fail
75  * to compile if <pcap.h> has already been included; including the headers
76  * in the opposite order works fine.
77  */
78 #ifdef HAVE_CAPSICUM
79 #include <sys/capability.h>
80 #include <sys/ioccom.h>
81 #include <net/bpf.h>
82 #include <libgen.h>
83 #endif	/* HAVE_CAPSICUM */
84 #include <pcap.h>
85 #include <signal.h>
86 #include <stdio.h>
87 #include <stdarg.h>
88 #include <stdlib.h>
89 #include <string.h>
90 #include <limits.h>
91 #ifndef _WIN32
92 #include <sys/wait.h>
93 #include <sys/resource.h>
94 #include <pwd.h>
95 #include <grp.h>
96 #endif /* _WIN32 */
97 
98 /* capabilities convenience library */
99 /* If a code depends on HAVE_LIBCAP_NG, it depends also on HAVE_CAP_NG_H.
100  * If HAVE_CAP_NG_H is not defined, undefine HAVE_LIBCAP_NG.
101  * Thus, the later tests are done only on HAVE_LIBCAP_NG.
102  */
103 #ifdef HAVE_LIBCAP_NG
104 #ifdef HAVE_CAP_NG_H
105 #include <cap-ng.h>
106 #else
107 #undef HAVE_LIBCAP_NG
108 #endif /* HAVE_CAP_NG_H */
109 #endif /* HAVE_LIBCAP_NG */
110 
111 #include "netdissect.h"
112 #include "interface.h"
113 #include "addrtoname.h"
114 #include "machdep.h"
115 #include "setsignal.h"
116 #include "gmt2local.h"
117 #include "pcap-missing.h"
118 #include "ascii_strcasecmp.h"
119 
120 #include "print.h"
121 
122 #ifndef PATH_MAX
123 #define PATH_MAX 1024
124 #endif
125 
126 #ifdef SIGINFO
127 #define SIGNAL_REQ_INFO SIGINFO
128 #elif SIGUSR1
129 #define SIGNAL_REQ_INFO SIGUSR1
130 #endif
131 
132 static int Bflag;			/* buffer size */
133 static long Cflag;			/* rotate dump files after this many bytes */
134 static int Cflag_count;			/* Keep track of which file number we're writing */
135 static int Dflag;			/* list available devices and exit */
136 /*
137  * This is exported because, in some versions of libpcap, if libpcap
138  * is built with optimizer debugging code (which is *NOT* the default
139  * configuration!), the library *imports*(!) a variable named dflag,
140  * under the expectation that tcpdump is exporting it, to govern
141  * how much debugging information to print when optimizing
142  * the generated BPF code.
143  *
144  * This is a horrible hack; newer versions of libpcap don't import
145  * dflag but, instead, *if* built with optimizer debugging code,
146  * *export* a routine to set that flag.
147  */
148 int dflag;				/* print filter code */
149 static int Gflag;			/* rotate dump files after this many seconds */
150 static int Gflag_count;			/* number of files created with Gflag rotation */
151 static time_t Gflag_time;		/* The last time_t the dump file was rotated. */
152 static int Lflag;			/* list available data link types and exit */
153 static int Iflag;			/* rfmon (monitor) mode */
154 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
155 static int Jflag;			/* list available time stamp types */
156 #endif
157 static int jflag = -1;			/* packet time stamp source */
158 static int pflag;			/* don't go promiscuous */
159 #ifdef HAVE_PCAP_SETDIRECTION
160 static int Qflag = -1;			/* restrict captured packet by send/receive direction */
161 #endif
162 static int Uflag;			/* "unbuffered" output of dump files */
163 static int Wflag;			/* recycle output files after this number of files */
164 static int WflagChars;
165 static char *zflag = NULL;		/* compress each savefile using a specified command (like gzip or bzip2) */
166 static int immediate_mode;
167 
168 static int infodelay;
169 static int infoprint;
170 
171 char *program_name;
172 
173 /* Forwards */
174 static void error(FORMAT_STRING(const char *), ...) NORETURN PRINTFLIKE(1, 2);
175 static void warning(FORMAT_STRING(const char *), ...) PRINTFLIKE(1, 2);
176 static void exit_tcpdump(int) NORETURN;
177 static RETSIGTYPE cleanup(int);
178 static RETSIGTYPE child_cleanup(int);
179 static void print_version(void);
180 static void print_usage(void);
181 static void show_tstamp_types_and_exit(pcap_t *, const char *device) NORETURN;
182 static void show_dlts_and_exit(pcap_t *, const char *device) NORETURN;
183 #ifdef HAVE_PCAP_FINDALLDEVS
184 static void show_devices_and_exit (void) NORETURN;
185 #endif
186 
187 static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
188 static void dump_packet_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *);
189 static void dump_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
190 static void droproot(const char *, const char *);
191 
192 #ifdef SIGNAL_REQ_INFO
193 RETSIGTYPE requestinfo(int);
194 #endif
195 
196 #if defined(USE_WIN32_MM_TIMER)
197   #include <MMsystem.h>
198   static UINT timer_id;
199   static void CALLBACK verbose_stats_dump(UINT, UINT, DWORD_PTR, DWORD_PTR, DWORD_PTR);
200 #elif defined(HAVE_ALARM)
201   static void verbose_stats_dump(int sig);
202 #endif
203 
204 static void info(int);
205 static u_int packets_captured;
206 
207 #ifdef HAVE_PCAP_FINDALLDEVS
208 static const struct tok status_flags[] = {
209 #ifdef PCAP_IF_UP
210 	{ PCAP_IF_UP,       "Up"       },
211 #endif
212 #ifdef PCAP_IF_RUNNING
213 	{ PCAP_IF_RUNNING,  "Running"  },
214 #endif
215 	{ PCAP_IF_LOOPBACK, "Loopback" },
216 	{ 0, NULL }
217 };
218 #endif
219 
220 static pcap_t *pd;
221 
222 static int supports_monitor_mode;
223 
224 extern int optind;
225 extern int opterr;
226 extern char *optarg;
227 
228 struct dump_info {
229 	char	*WFileName;
230 	char	*CurrentFileName;
231 	pcap_t	*pd;
232 	pcap_dumper_t *p;
233 #ifdef HAVE_CAPSICUM
234 	int	dirfd;
235 #endif
236 };
237 
238 #if defined(HAVE_PCAP_SET_PARSER_DEBUG)
239 /*
240  * We have pcap_set_parser_debug() in libpcap; declare it (it's not declared
241  * by any libpcap header, because it's a special hack, only available if
242  * libpcap was configured to include it, and only intended for use by
243  * libpcap developers trying to debug the parser for filter expressions).
244  */
245 #ifdef _WIN32
246 __declspec(dllimport)
247 #else /* _WIN32 */
248 extern
249 #endif /* _WIN32 */
250 void pcap_set_parser_debug(int);
251 #elif defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG)
252 /*
253  * We don't have pcap_set_parser_debug() in libpcap, but we do have
254  * pcap_debug or yydebug.  Make a local version of pcap_set_parser_debug()
255  * to set the flag, and define HAVE_PCAP_SET_PARSER_DEBUG.
256  */
257 static void
pcap_set_parser_debug(int value)258 pcap_set_parser_debug(int value)
259 {
260 #ifdef HAVE_PCAP_DEBUG
261 	extern int pcap_debug;
262 
263 	pcap_debug = value;
264 #else /* HAVE_PCAP_DEBUG */
265 	extern int yydebug;
266 
267 	yydebug = value;
268 #endif /* HAVE_PCAP_DEBUG */
269 }
270 
271 #define HAVE_PCAP_SET_PARSER_DEBUG
272 #endif
273 
274 #if defined(HAVE_PCAP_SET_OPTIMIZER_DEBUG)
275 /*
276  * We have pcap_set_optimizer_debug() in libpcap; declare it (it's not declared
277  * by any libpcap header, because it's a special hack, only available if
278  * libpcap was configured to include it, and only intended for use by
279  * libpcap developers trying to debug the optimizer for filter expressions).
280  */
281 #ifdef _WIN32
282 __declspec(dllimport)
283 #else /* _WIN32 */
284 extern
285 #endif /* _WIN32 */
286 void pcap_set_optimizer_debug(int);
287 #endif
288 
289 /* VARARGS */
290 static void
error(const char * fmt,...)291 error(const char *fmt, ...)
292 {
293 	va_list ap;
294 
295 	(void)fprintf(stderr, "%s: ", program_name);
296 	va_start(ap, fmt);
297 	(void)vfprintf(stderr, fmt, ap);
298 	va_end(ap);
299 	if (*fmt) {
300 		fmt += strlen(fmt);
301 		if (fmt[-1] != '\n')
302 			(void)fputc('\n', stderr);
303 	}
304 	exit_tcpdump(1);
305 	/* NOTREACHED */
306 }
307 
308 /* VARARGS */
309 static void
warning(const char * fmt,...)310 warning(const char *fmt, ...)
311 {
312 	va_list ap;
313 
314 	(void)fprintf(stderr, "%s: WARNING: ", program_name);
315 	va_start(ap, fmt);
316 	(void)vfprintf(stderr, fmt, ap);
317 	va_end(ap);
318 	if (*fmt) {
319 		fmt += strlen(fmt);
320 		if (fmt[-1] != '\n')
321 			(void)fputc('\n', stderr);
322 	}
323 }
324 
325 static void
exit_tcpdump(int status)326 exit_tcpdump(int status)
327 {
328 	nd_cleanup();
329 	exit(status);
330 }
331 
332 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
333 static void
show_tstamp_types_and_exit(pcap_t * pc,const char * device)334 show_tstamp_types_and_exit(pcap_t *pc, const char *device)
335 {
336 	int n_tstamp_types;
337 	int *tstamp_types = 0;
338 	const char *tstamp_type_name;
339 	int i;
340 
341 	n_tstamp_types = pcap_list_tstamp_types(pc, &tstamp_types);
342 	if (n_tstamp_types < 0)
343 		error("%s", pcap_geterr(pc));
344 
345 	if (n_tstamp_types == 0) {
346 		fprintf(stderr, "Time stamp type cannot be set for %s\n",
347 		    device);
348 		exit_tcpdump(0);
349 	}
350 	fprintf(stderr, "Time stamp types for %s (use option -j to set):\n",
351 	    device);
352 	for (i = 0; i < n_tstamp_types; i++) {
353 		tstamp_type_name = pcap_tstamp_type_val_to_name(tstamp_types[i]);
354 		if (tstamp_type_name != NULL) {
355 			(void) fprintf(stderr, "  %s (%s)\n", tstamp_type_name,
356 			    pcap_tstamp_type_val_to_description(tstamp_types[i]));
357 		} else {
358 			(void) fprintf(stderr, "  %d\n", tstamp_types[i]);
359 		}
360 	}
361 	pcap_free_tstamp_types(tstamp_types);
362 	exit_tcpdump(0);
363 }
364 #endif
365 
366 static void
show_dlts_and_exit(pcap_t * pc,const char * device)367 show_dlts_and_exit(pcap_t *pc, const char *device)
368 {
369 	int n_dlts, i;
370 	int *dlts = 0;
371 	const char *dlt_name;
372 
373 	n_dlts = pcap_list_datalinks(pc, &dlts);
374 	if (n_dlts < 0)
375 		error("%s", pcap_geterr(pc));
376 	else if (n_dlts == 0 || !dlts)
377 		error("No data link types.");
378 
379 	/*
380 	 * If the interface is known to support monitor mode, indicate
381 	 * whether these are the data link types available when not in
382 	 * monitor mode, if -I wasn't specified, or when in monitor mode,
383 	 * when -I was specified (the link-layer types available in
384 	 * monitor mode might be different from the ones available when
385 	 * not in monitor mode).
386 	 */
387 	if (supports_monitor_mode)
388 		(void) fprintf(stderr, "Data link types for %s %s (use option -y to set):\n",
389 		    device,
390 		    Iflag ? "when in monitor mode" : "when not in monitor mode");
391 	else
392 		(void) fprintf(stderr, "Data link types for %s (use option -y to set):\n",
393 		    device);
394 
395 	for (i = 0; i < n_dlts; i++) {
396 		dlt_name = pcap_datalink_val_to_name(dlts[i]);
397 		if (dlt_name != NULL) {
398 			(void) fprintf(stderr, "  %s (%s)", dlt_name,
399 			    pcap_datalink_val_to_description(dlts[i]));
400 
401 			/*
402 			 * OK, does tcpdump handle that type?
403 			 */
404 			if (!has_printer(dlts[i]))
405 				(void) fprintf(stderr, " (printing not supported)");
406 			fprintf(stderr, "\n");
407 		} else {
408 			(void) fprintf(stderr, "  DLT %d (printing not supported)\n",
409 			    dlts[i]);
410 		}
411 	}
412 #ifdef HAVE_PCAP_FREE_DATALINKS
413 	pcap_free_datalinks(dlts);
414 #endif
415 	exit_tcpdump(0);
416 }
417 
418 #ifdef HAVE_PCAP_FINDALLDEVS
419 static void
show_devices_and_exit(void)420 show_devices_and_exit (void)
421 {
422 	pcap_if_t *dev, *devlist;
423 	char ebuf[PCAP_ERRBUF_SIZE];
424 	int i;
425 
426 	if (pcap_findalldevs(&devlist, ebuf) < 0)
427 		error("%s", ebuf);
428 	for (i = 0, dev = devlist; dev != NULL; i++, dev = dev->next) {
429 		printf("%d.%s", i+1, dev->name);
430 		if (dev->description != NULL)
431 			printf(" (%s)", dev->description);
432 		if (dev->flags != 0)
433 			printf(" [%s]", bittok2str(status_flags, "none", dev->flags));
434 		printf("\n");
435 	}
436 	pcap_freealldevs(devlist);
437 	exit_tcpdump(0);
438 }
439 #endif /* HAVE_PCAP_FINDALLDEVS */
440 
441 /*
442  * Short options.
443  *
444  * Note that there we use all letters for short options except for g, k,
445  * o, and P, and those are used by other versions of tcpdump, and we should
446  * only use them for the same purposes that the other versions of tcpdump
447  * use them:
448  *
449  * OS X tcpdump uses -g to force non--v output for IP to be on one
450  * line, making it more "g"repable;
451  *
452  * OS X tcpdump uses -k to specify that packet comments in pcap-ng files
453  * should be printed;
454  *
455  * OpenBSD tcpdump uses -o to indicate that OS fingerprinting should be done
456  * for hosts sending TCP SYN packets;
457  *
458  * OS X tcpdump uses -P to indicate that -w should write pcap-ng rather
459  * than pcap files.
460  *
461  * OS X tcpdump also uses -Q to specify expressions that match packet
462  * metadata, including but not limited to the packet direction.
463  * The expression syntax is different from a simple "in|out|inout",
464  * and those expressions aren't accepted by OS X tcpdump, but the
465  * equivalents would be "in" = "dir=in", "out" = "dir=out", and
466  * "inout" = "dir=in or dir=out", and the parser could conceivably
467  * special-case "in", "out", and "inout" as expressions for backwards
468  * compatibility, so all is not (yet) lost.
469  */
470 
471 /*
472  * Set up flags that might or might not be supported depending on the
473  * version of libpcap we're using.
474  */
475 #if defined(HAVE_PCAP_CREATE) || defined(_WIN32)
476 #define B_FLAG		"B:"
477 #define B_FLAG_USAGE	" [ -B size ]"
478 #else /* defined(HAVE_PCAP_CREATE) || defined(_WIN32) */
479 #define B_FLAG
480 #define B_FLAG_USAGE
481 #endif /* defined(HAVE_PCAP_CREATE) || defined(_WIN32) */
482 
483 #ifdef HAVE_PCAP_CREATE
484 #define I_FLAG		"I"
485 #else /* HAVE_PCAP_CREATE */
486 #define I_FLAG
487 #endif /* HAVE_PCAP_CREATE */
488 
489 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
490 #define j_FLAG		"j:"
491 #define j_FLAG_USAGE	" [ -j tstamptype ]"
492 #define J_FLAG		"J"
493 #else /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */
494 #define j_FLAG
495 #define j_FLAG_USAGE
496 #define J_FLAG
497 #endif /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */
498 
499 #ifdef HAVE_PCAP_FINDALLDEVS
500 #define D_FLAG	"D"
501 #else
502 #define D_FLAG
503 #endif
504 
505 #ifdef HAVE_PCAP_DUMP_FLUSH
506 #define U_FLAG	"U"
507 #else
508 #define U_FLAG
509 #endif
510 
511 #ifdef HAVE_PCAP_SETDIRECTION
512 #define Q_FLAG "Q:"
513 #else
514 #define Q_FLAG
515 #endif
516 
517 #define SHORTOPTS "aAb" B_FLAG "c:C:d" D_FLAG "eE:fF:G:hHi:" I_FLAG j_FLAG J_FLAG "KlLm:M:nNOpq" Q_FLAG "r:s:StT:u" U_FLAG "vV:w:W:xXy:Yz:Z:#"
518 
519 /*
520  * Long options.
521  *
522  * We do not currently have long options corresponding to all short
523  * options; we should probably pick appropriate option names for them.
524  *
525  * However, the short options where the number of times the option is
526  * specified matters, such as -v and -d and -t, should probably not
527  * just map to a long option, as saying
528  *
529  *  tcpdump --verbose --verbose
530  *
531  * doesn't make sense; it should be --verbosity={N} or something such
532  * as that.
533  *
534  * For long options with no corresponding short options, we define values
535  * outside the range of ASCII graphic characters, make that the last
536  * component of the entry for the long option, and have a case for that
537  * option in the switch statement.
538  */
539 #define OPTION_VERSION		128
540 #define OPTION_TSTAMP_PRECISION	129
541 #define OPTION_IMMEDIATE_MODE	130
542 
543 static const struct option longopts[] = {
544 #if defined(HAVE_PCAP_CREATE) || defined(_WIN32)
545 	{ "buffer-size", required_argument, NULL, 'B' },
546 #endif
547 	{ "list-interfaces", no_argument, NULL, 'D' },
548 	{ "help", no_argument, NULL, 'h' },
549 	{ "interface", required_argument, NULL, 'i' },
550 #ifdef HAVE_PCAP_CREATE
551 	{ "monitor-mode", no_argument, NULL, 'I' },
552 #endif
553 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
554 	{ "time-stamp-type", required_argument, NULL, 'j' },
555 	{ "list-time-stamp-types", no_argument, NULL, 'J' },
556 #endif
557 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
558 	{ "time-stamp-precision", required_argument, NULL, OPTION_TSTAMP_PRECISION},
559 #endif
560 	{ "dont-verify-checksums", no_argument, NULL, 'K' },
561 	{ "list-data-link-types", no_argument, NULL, 'L' },
562 	{ "no-optimize", no_argument, NULL, 'O' },
563 	{ "no-promiscuous-mode", no_argument, NULL, 'p' },
564 #ifdef HAVE_PCAP_SETDIRECTION
565 	{ "direction", required_argument, NULL, 'Q' },
566 #endif
567 	{ "snapshot-length", required_argument, NULL, 's' },
568 	{ "absolute-tcp-sequence-numbers", no_argument, NULL, 'S' },
569 #ifdef HAVE_PCAP_DUMP_FLUSH
570 	{ "packet-buffered", no_argument, NULL, 'U' },
571 #endif
572 	{ "linktype", required_argument, NULL, 'y' },
573 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
574 	{ "immediate-mode", no_argument, NULL, OPTION_IMMEDIATE_MODE },
575 #endif
576 #ifdef HAVE_PCAP_SET_PARSER_DEBUG
577 	{ "debug-filter-parser", no_argument, NULL, 'Y' },
578 #endif
579 	{ "relinquish-privileges", required_argument, NULL, 'Z' },
580 	{ "number", no_argument, NULL, '#' },
581 	{ "version", no_argument, NULL, OPTION_VERSION },
582 	{ NULL, 0, NULL, 0 }
583 };
584 
585 #ifndef _WIN32
586 /* Drop root privileges and chroot if necessary */
587 static void
droproot(const char * username,const char * chroot_dir)588 droproot(const char *username, const char *chroot_dir)
589 {
590 	struct passwd *pw = NULL;
591 
592 	if (chroot_dir && !username) {
593 		fprintf(stderr, "%s: Chroot without dropping root is insecure\n",
594 			program_name);
595 		exit_tcpdump(1);
596 	}
597 
598 	pw = getpwnam(username);
599 	if (pw) {
600 		if (chroot_dir) {
601 			if (chroot(chroot_dir) != 0 || chdir ("/") != 0) {
602 				fprintf(stderr, "%s: Couldn't chroot/chdir to '%.64s': %s\n",
603 					program_name, chroot_dir, pcap_strerror(errno));
604 				exit_tcpdump(1);
605 			}
606 		}
607 #ifdef HAVE_LIBCAP_NG
608 		{
609 			int ret = capng_change_id(pw->pw_uid, pw->pw_gid, CAPNG_NO_FLAG);
610 			if (ret < 0) {
611 				fprintf(stderr, "error : ret %d\n", ret);
612 			} else {
613 				fprintf(stderr, "dropped privs to %s\n", username);
614 			}
615 		}
616 #else
617 		if (initgroups(pw->pw_name, pw->pw_gid) != 0 ||
618 		    setgid(pw->pw_gid) != 0 || setuid(pw->pw_uid) != 0) {
619 			fprintf(stderr, "%s: Couldn't change to '%.32s' uid=%lu gid=%lu: %s\n",
620 				program_name, username,
621 				(unsigned long)pw->pw_uid,
622 				(unsigned long)pw->pw_gid,
623 				pcap_strerror(errno));
624 			exit_tcpdump(1);
625 		}
626 		else {
627 			fprintf(stderr, "dropped privs to %s\n", username);
628 		}
629 #endif /* HAVE_LIBCAP_NG */
630 	}
631 	else {
632 		fprintf(stderr, "%s: Couldn't find user '%.32s'\n",
633 			program_name, username);
634 		exit_tcpdump(1);
635 	}
636 #ifdef HAVE_LIBCAP_NG
637 	/* We don't need CAP_SETUID, CAP_SETGID and CAP_SYS_CHROOT any more. */
638 	capng_updatev(
639 		CAPNG_DROP,
640 		CAPNG_EFFECTIVE | CAPNG_PERMITTED,
641 		CAP_SETUID,
642 		CAP_SETGID,
643 		CAP_SYS_CHROOT,
644 		-1);
645 	capng_apply(CAPNG_SELECT_BOTH);
646 #endif /* HAVE_LIBCAP_NG */
647 
648 }
649 #endif /* _WIN32 */
650 
651 static int
getWflagChars(int x)652 getWflagChars(int x)
653 {
654 	int c = 0;
655 
656 	x -= 1;
657 	while (x > 0) {
658 		c += 1;
659 		x /= 10;
660 	}
661 
662 	return c;
663 }
664 
665 
666 static void
MakeFilename(char * buffer,char * orig_name,int cnt,int max_chars)667 MakeFilename(char *buffer, char *orig_name, int cnt, int max_chars)
668 {
669         char *filename = malloc(PATH_MAX + 1);
670         if (filename == NULL)
671             error("Makefilename: malloc");
672 
673         /* Process with strftime if Gflag is set. */
674         if (Gflag != 0) {
675           struct tm *local_tm;
676 
677           /* Convert Gflag_time to a usable format */
678           if ((local_tm = localtime(&Gflag_time)) == NULL) {
679                   error("MakeTimedFilename: localtime");
680           }
681 
682           /* There's no good way to detect an error in strftime since a return
683            * value of 0 isn't necessarily failure.
684            */
685           strftime(filename, PATH_MAX, orig_name, local_tm);
686         } else {
687           strncpy(filename, orig_name, PATH_MAX);
688         }
689 
690 	if (cnt == 0 && max_chars == 0)
691 		strncpy(buffer, filename, PATH_MAX + 1);
692 	else
693 		if (snprintf(buffer, PATH_MAX + 1, "%s%0*d", filename, max_chars, cnt) > PATH_MAX)
694                   /* Report an error if the filename is too large */
695                   error("too many output files or filename is too long (> %d)", PATH_MAX);
696         free(filename);
697 }
698 
699 static char *
get_next_file(FILE * VFile,char * ptr)700 get_next_file(FILE *VFile, char *ptr)
701 {
702 	char *ret;
703 
704 	ret = fgets(ptr, PATH_MAX, VFile);
705 	if (!ret)
706 		return NULL;
707 
708 	if (ptr[strlen(ptr) - 1] == '\n')
709 		ptr[strlen(ptr) - 1] = '\0';
710 
711 	return ret;
712 }
713 
714 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
715 static int
tstamp_precision_from_string(const char * precision)716 tstamp_precision_from_string(const char *precision)
717 {
718 	if (strncmp(precision, "nano", strlen("nano")) == 0)
719 		return PCAP_TSTAMP_PRECISION_NANO;
720 
721 	if (strncmp(precision, "micro", strlen("micro")) == 0)
722 		return PCAP_TSTAMP_PRECISION_MICRO;
723 
724 	return -EINVAL;
725 }
726 
727 static const char *
tstamp_precision_to_string(int precision)728 tstamp_precision_to_string(int precision)
729 {
730 	switch (precision) {
731 
732 	case PCAP_TSTAMP_PRECISION_MICRO:
733 		return "micro";
734 
735 	case PCAP_TSTAMP_PRECISION_NANO:
736 		return "nano";
737 
738 	default:
739 		return "unknown";
740 	}
741 }
742 #endif
743 
744 #ifdef HAVE_CAPSICUM
745 /*
746  * Ensure that, on a dump file's descriptor, we have all the rights
747  * necessary to make the standard I/O library work with an fdopen()ed
748  * FILE * from that descriptor.
749  *
750  * A long time ago, in a galaxy far far away, AT&T decided that, instead
751  * of providing separate APIs for getting and setting the FD_ flags on a
752  * descriptor, getting and setting the O_ flags on a descriptor, and
753  * locking files, they'd throw them all into a kitchen-sink fcntl() call
754  * along the lines of ioctl(), the fact that ioctl() operations are
755  * largely specific to particular character devices but fcntl() operations
756  * are either generic to all descriptors or generic to all descriptors for
757  * regular files nonwithstanding.
758  *
759  * The Capsicum people decided that fine-grained control of descriptor
760  * operations was required, so that you need to grant permission for
761  * reading, writing, seeking, and fcntl-ing.  The latter, courtesy of
762  * AT&T's decision, means that "fcntl-ing" isn't a thing, but a motley
763  * collection of things, so there are *individual* fcntls for which
764  * permission needs to be granted.
765  *
766  * The FreeBSD standard I/O people implemented some optimizations that
767  * requires that the standard I/O routines be able to determine whether
768  * the descriptor for the FILE * is open append-only or not; as that
769  * descriptor could have come from an open() rather than an fopen(),
770  * that requires that it be able to do an F_GETFL fcntl() to read
771  * the O_ flags.
772  *
773  * Tcpdump uses ftell() to determine how much data has been written
774  * to a file in order to, when used with -C, determine when it's time
775  * to rotate capture files.  ftell() therefore needs to do an lseek()
776  * to find out the file offset and must, thanks to the aforementioned
777  * optimization, also know whether the descriptor is open append-only
778  * or not.
779  *
780  * The net result of all the above is that we need to grant CAP_SEEK,
781  * CAP_WRITE, and CAP_FCNTL with the CAP_FCNTL_GETFL subcapability.
782  *
783  * Perhaps this is the universe's way of saying that either
784  *
785  *	1) there needs to be an fopenat() call and a pcap_dump_openat() call
786  *	   using it, so that Capsicum-capable tcpdump wouldn't need to do
787  *	   an fdopen()
788  *
789  * or
790  *
791  *	2) there needs to be a cap_fdopen() call in the FreeBSD standard
792  *	   I/O library that knows what rights are needed by the standard
793  *	   I/O library, based on the open mode, and assigns them, perhaps
794  *	   with an additional argument indicating, for example, whether
795  *	   seeking should be allowed, so that tcpdump doesn't need to know
796  *	   what the standard I/O library happens to require this week.
797  */
798 static void
set_dumper_capsicum_rights(pcap_dumper_t * p)799 set_dumper_capsicum_rights(pcap_dumper_t *p)
800 {
801 	int fd = fileno(pcap_dump_file(p));
802 	cap_rights_t rights;
803 
804 	cap_rights_init(&rights, CAP_SEEK, CAP_WRITE, CAP_FCNTL);
805 	if (cap_rights_limit(fd, &rights) < 0 && errno != ENOSYS) {
806 		error("unable to limit dump descriptor");
807 	}
808 	if (cap_fcntls_limit(fd, CAP_FCNTL_GETFL) < 0 && errno != ENOSYS) {
809 		error("unable to limit dump descriptor fcntls");
810 	}
811 }
812 #endif
813 
814 /*
815  * Copy arg vector into a new buffer, concatenating arguments with spaces.
816  */
817 static char *
copy_argv(register char ** argv)818 copy_argv(register char **argv)
819 {
820 	register char **p;
821 	register u_int len = 0;
822 	char *buf;
823 	char *src, *dst;
824 
825 	p = argv;
826 	if (*p == NULL)
827 		return 0;
828 
829 	while (*p)
830 		len += strlen(*p++) + 1;
831 
832 	buf = (char *)malloc(len);
833 	if (buf == NULL)
834 		error("copy_argv: malloc");
835 
836 	p = argv;
837 	dst = buf;
838 	while ((src = *p++) != NULL) {
839 		while ((*dst++ = *src++) != '\0')
840 			;
841 		dst[-1] = ' ';
842 	}
843 	dst[-1] = '\0';
844 
845 	return buf;
846 }
847 
848 /*
849  * On Windows, we need to open the file in binary mode, so that
850  * we get all the bytes specified by the size we get from "fstat()".
851  * On UNIX, that's not necessary.  O_BINARY is defined on Windows;
852  * we define it as 0 if it's not defined, so it does nothing.
853  */
854 #ifndef O_BINARY
855 #define O_BINARY	0
856 #endif
857 
858 static char *
read_infile(char * fname)859 read_infile(char *fname)
860 {
861 	register int i, fd, cc;
862 	register char *cp;
863 	struct stat buf;
864 
865 	fd = open(fname, O_RDONLY|O_BINARY);
866 	if (fd < 0)
867 		error("can't open %s: %s", fname, pcap_strerror(errno));
868 
869 	if (fstat(fd, &buf) < 0)
870 		error("can't stat %s: %s", fname, pcap_strerror(errno));
871 
872 	cp = malloc((u_int)buf.st_size + 1);
873 	if (cp == NULL)
874 		error("malloc(%d) for %s: %s", (u_int)buf.st_size + 1,
875 			fname, pcap_strerror(errno));
876 	cc = read(fd, cp, (u_int)buf.st_size);
877 	if (cc < 0)
878 		error("read %s: %s", fname, pcap_strerror(errno));
879 	if (cc != buf.st_size)
880 		error("short read %s (%d != %d)", fname, cc, (int)buf.st_size);
881 
882 	close(fd);
883 	/* replace "# comment" with spaces */
884 	for (i = 0; i < cc; i++) {
885 		if (cp[i] == '#')
886 			while (i < cc && cp[i] != '\n')
887 				cp[i++] = ' ';
888 	}
889 	cp[cc] = '\0';
890 	return (cp);
891 }
892 
893 #ifdef HAVE_PCAP_FINDALLDEVS
894 static long
parse_interface_number(const char * device)895 parse_interface_number(const char *device)
896 {
897 	long devnum;
898 	char *end;
899 
900 	devnum = strtol(device, &end, 10);
901 	if (device != end && *end == '\0') {
902 		/*
903 		 * It's all-numeric, but is it a valid number?
904 		 */
905 		if (devnum <= 0) {
906 			/*
907 			 * No, it's not an ordinal.
908 			 */
909 			error("Invalid adapter index");
910 		}
911 		return (devnum);
912 	} else {
913 		/*
914 		 * It's not all-numeric; return -1, so our caller
915 		 * knows that.
916 		 */
917 		return (-1);
918 	}
919 }
920 
921 static char *
find_interface_by_number(long devnum)922 find_interface_by_number(long devnum)
923 {
924 	pcap_if_t *dev, *devlist;
925 	long i;
926 	char ebuf[PCAP_ERRBUF_SIZE];
927 	char *device;
928 
929 	if (pcap_findalldevs(&devlist, ebuf) < 0)
930 		error("%s", ebuf);
931 	/*
932 	 * Look for the devnum-th entry in the list of devices (1-based).
933 	 */
934 	for (i = 0, dev = devlist; i < devnum-1 && dev != NULL;
935 	    i++, dev = dev->next)
936 		;
937 	if (dev == NULL)
938 		error("Invalid adapter index");
939 	device = strdup(dev->name);
940 	pcap_freealldevs(devlist);
941 	return (device);
942 }
943 #endif
944 
945 static pcap_t *
open_interface(const char * device,netdissect_options * ndo,char * ebuf)946 open_interface(const char *device, netdissect_options *ndo, char *ebuf)
947 {
948 	pcap_t *pc;
949 #ifdef HAVE_PCAP_CREATE
950 	int status;
951 	char *cp;
952 #endif
953 
954 #ifdef HAVE_PCAP_CREATE
955 	pc = pcap_create(device, ebuf);
956 	if (pc == NULL) {
957 		/*
958 		 * If this failed with "No such device", that means
959 		 * the interface doesn't exist; return NULL, so that
960 		 * the caller can see whether the device name is
961 		 * actually an interface index.
962 		 */
963 		if (strstr(ebuf, "No such device") != NULL)
964 			return (NULL);
965 		error("%s", ebuf);
966 	}
967 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
968 	if (Jflag)
969 		show_tstamp_types_and_exit(pc, device);
970 #endif
971 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
972 	status = pcap_set_tstamp_precision(pc, ndo->ndo_tstamp_precision);
973 	if (status != 0)
974 		error("%s: Can't set %ssecond time stamp precision: %s",
975 			device,
976 			tstamp_precision_to_string(ndo->ndo_tstamp_precision),
977 			pcap_statustostr(status));
978 #endif
979 
980 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
981 	if (immediate_mode) {
982 		status = pcap_set_immediate_mode(pc, 1);
983 		if (status != 0)
984 			error("%s: Can't set immediate mode: %s",
985 			device,
986 			pcap_statustostr(status));
987 	}
988 #endif
989 	/*
990 	 * Is this an interface that supports monitor mode?
991 	 */
992 	if (pcap_can_set_rfmon(pc) == 1)
993 		supports_monitor_mode = 1;
994 	else
995 		supports_monitor_mode = 0;
996 	status = pcap_set_snaplen(pc, ndo->ndo_snaplen);
997 	if (status != 0)
998 		error("%s: Can't set snapshot length: %s",
999 		    device, pcap_statustostr(status));
1000 	status = pcap_set_promisc(pc, !pflag);
1001 	if (status != 0)
1002 		error("%s: Can't set promiscuous mode: %s",
1003 		    device, pcap_statustostr(status));
1004 	if (Iflag) {
1005 		status = pcap_set_rfmon(pc, 1);
1006 		if (status != 0)
1007 			error("%s: Can't set monitor mode: %s",
1008 			    device, pcap_statustostr(status));
1009 	}
1010 	status = pcap_set_timeout(pc, 1000);
1011 	if (status != 0)
1012 		error("%s: pcap_set_timeout failed: %s",
1013 		    device, pcap_statustostr(status));
1014 	if (Bflag != 0) {
1015 		status = pcap_set_buffer_size(pc, Bflag);
1016 		if (status != 0)
1017 			error("%s: Can't set buffer size: %s",
1018 			    device, pcap_statustostr(status));
1019 	}
1020 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
1021 	if (jflag != -1) {
1022 		status = pcap_set_tstamp_type(pc, jflag);
1023 		if (status < 0)
1024 			error("%s: Can't set time stamp type: %s",
1025 		              device, pcap_statustostr(status));
1026 	}
1027 #endif
1028 	status = pcap_activate(pc);
1029 	if (status < 0) {
1030 		/*
1031 		 * pcap_activate() failed.
1032 		 */
1033 		cp = pcap_geterr(pc);
1034 		if (status == PCAP_ERROR)
1035 			error("%s", cp);
1036 		else if (status == PCAP_ERROR_NO_SUCH_DEVICE) {
1037 			/*
1038 			 * Return an error for our caller to handle.
1039 			 */
1040 			snprintf(ebuf, PCAP_ERRBUF_SIZE, "%s: %s\n(%s)",
1041 			    device, pcap_statustostr(status), cp);
1042 			pcap_close(pc);
1043 			return (NULL);
1044 		} else if (status == PCAP_ERROR_PERM_DENIED && *cp != '\0')
1045 			error("%s: %s\n(%s)", device,
1046 			    pcap_statustostr(status), cp);
1047 		else
1048 			error("%s: %s", device,
1049 			    pcap_statustostr(status));
1050 	} else if (status > 0) {
1051 		/*
1052 		 * pcap_activate() succeeded, but it's warning us
1053 		 * of a problem it had.
1054 		 */
1055 		cp = pcap_geterr(pc);
1056 		if (status == PCAP_WARNING)
1057 			warning("%s", cp);
1058 		else if (status == PCAP_WARNING_PROMISC_NOTSUP &&
1059 		         *cp != '\0')
1060 			warning("%s: %s\n(%s)", device,
1061 			    pcap_statustostr(status), cp);
1062 		else
1063 			warning("%s: %s", device,
1064 			    pcap_statustostr(status));
1065 	}
1066 #ifdef HAVE_PCAP_SETDIRECTION
1067 	if (Qflag != -1) {
1068 		status = pcap_setdirection(pc, Qflag);
1069 		if (status != 0)
1070 			error("%s: pcap_setdirection() failed: %s",
1071 			      device,  pcap_geterr(pc));
1072 		}
1073 #endif /* HAVE_PCAP_SETDIRECTION */
1074 #else /* HAVE_PCAP_CREATE */
1075 	*ebuf = '\0';
1076 	pc = pcap_open_live(device, ndo->ndo_snaplen, !pflag, 1000, ebuf);
1077 	if (pc == NULL) {
1078 		/*
1079 		 * If this failed with "No such device", that means
1080 		 * the interface doesn't exist; return NULL, so that
1081 		 * the caller can see whether the device name is
1082 		 * actually an interface index.
1083 		 */
1084 		if (strstr(ebuf, "No such device") != NULL)
1085 			return (NULL);
1086 		error("%s", ebuf);
1087 	}
1088 	if (*ebuf)
1089 		warning("%s", ebuf);
1090 #endif /* HAVE_PCAP_CREATE */
1091 
1092 	return (pc);
1093 }
1094 
1095 int
main(int argc,char ** argv)1096 main(int argc, char **argv)
1097 {
1098 	register int cnt, op, i;
1099 	bpf_u_int32 localnet =0 , netmask = 0;
1100 	int timezone_offset = 0;
1101 	register char *cp, *infile, *cmdbuf, *device, *RFileName, *VFileName, *WFileName;
1102 	pcap_handler callback;
1103 	int dlt;
1104 	const char *dlt_name;
1105 	struct bpf_program fcode;
1106 #ifndef _WIN32
1107 	RETSIGTYPE (*oldhandler)(int);
1108 #endif
1109 	struct dump_info dumpinfo;
1110 	u_char *pcap_userdata;
1111 	char ebuf[PCAP_ERRBUF_SIZE];
1112 	char VFileLine[PATH_MAX + 1];
1113 	char *username = NULL;
1114 	char *chroot_dir = NULL;
1115 	char *ret = NULL;
1116 	char *end;
1117 #ifdef HAVE_PCAP_FINDALLDEVS
1118 	pcap_if_t *devlist;
1119 	long devnum;
1120 #endif
1121 	int status;
1122 	FILE *VFile;
1123 #ifdef HAVE_CAPSICUM
1124 	cap_rights_t rights;
1125 	int cansandbox;
1126 #endif	/* HAVE_CAPSICUM */
1127 	int Oflag = 1;			/* run filter code optimizer */
1128 	int yflag_dlt = -1;
1129 	const char *yflag_dlt_name = NULL;
1130 
1131 	netdissect_options Ndo;
1132 	netdissect_options *ndo = &Ndo;
1133 
1134 	/*
1135 	 * Initialize the netdissect code.
1136 	 */
1137 	if (nd_init(ebuf, sizeof ebuf) == -1)
1138 		error("%s", ebuf);
1139 
1140 	memset(ndo, 0, sizeof(*ndo));
1141 	ndo_set_function_pointers(ndo);
1142 	ndo->ndo_snaplen = DEFAULT_SNAPLEN;
1143 
1144 	cnt = -1;
1145 	device = NULL;
1146 	infile = NULL;
1147 	RFileName = NULL;
1148 	VFileName = NULL;
1149 	VFile = NULL;
1150 	WFileName = NULL;
1151 	dlt = -1;
1152 	if ((cp = strrchr(argv[0], '/')) != NULL)
1153 		ndo->program_name = program_name = cp + 1;
1154 	else
1155 		ndo->program_name = program_name = argv[0];
1156 
1157 #ifdef _WIN32
1158 	if (pcap_wsockinit() != 0)
1159 		error("Attempting to initialize Winsock failed");
1160 #endif /* _WIN32 */
1161 
1162 	/*
1163 	 * On platforms where the CPU doesn't support unaligned loads,
1164 	 * force unaligned accesses to abort with SIGBUS, rather than
1165 	 * being fixed up (slowly) by the OS kernel; on those platforms,
1166 	 * misaligned accesses are bugs, and we want tcpdump to crash so
1167 	 * that the bugs are reported.
1168 	 */
1169 	if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
1170 		error("%s", ebuf);
1171 
1172 	while (
1173 	    (op = getopt_long(argc, argv, SHORTOPTS, longopts, NULL)) != -1)
1174 		switch (op) {
1175 
1176 		case 'a':
1177 			/* compatibility for old -a */
1178 			break;
1179 
1180 		case 'A':
1181 			++ndo->ndo_Aflag;
1182 			break;
1183 
1184 		case 'b':
1185 			++ndo->ndo_bflag;
1186 			break;
1187 
1188 #if defined(HAVE_PCAP_CREATE) || defined(_WIN32)
1189 		case 'B':
1190 			Bflag = atoi(optarg)*1024;
1191 			if (Bflag <= 0)
1192 				error("invalid packet buffer size %s", optarg);
1193 			break;
1194 #endif /* defined(HAVE_PCAP_CREATE) || defined(_WIN32) */
1195 
1196 		case 'c':
1197 			cnt = atoi(optarg);
1198 			if (cnt <= 0)
1199 				error("invalid packet count %s", optarg);
1200 			break;
1201 
1202 		case 'C':
1203 			Cflag = atoi(optarg) * 1000000;
1204 			if (Cflag <= 0)
1205 				error("invalid file size %s", optarg);
1206 			break;
1207 
1208 		case 'd':
1209 			++dflag;
1210 			break;
1211 
1212 		case 'D':
1213 			Dflag++;
1214 			break;
1215 
1216 		case 'L':
1217 			Lflag++;
1218 			break;
1219 
1220 		case 'e':
1221 			++ndo->ndo_eflag;
1222 			break;
1223 
1224 		case 'E':
1225 #ifndef HAVE_LIBCRYPTO
1226 			warning("crypto code not compiled in");
1227 #endif
1228 			ndo->ndo_espsecret = optarg;
1229 			break;
1230 
1231 		case 'f':
1232 			++ndo->ndo_fflag;
1233 			break;
1234 
1235 		case 'F':
1236 			infile = optarg;
1237 			break;
1238 
1239 		case 'G':
1240 			Gflag = atoi(optarg);
1241 			if (Gflag < 0)
1242 				error("invalid number of seconds %s", optarg);
1243 
1244                         /* We will create one file initially. */
1245                         Gflag_count = 0;
1246 
1247 			/* Grab the current time for rotation use. */
1248 			if ((Gflag_time = time(NULL)) == (time_t)-1) {
1249 				error("main: can't get current time: %s",
1250 				    pcap_strerror(errno));
1251 			}
1252 			break;
1253 
1254 		case 'h':
1255 			print_usage();
1256 			exit_tcpdump(0);
1257 			break;
1258 
1259 		case 'H':
1260 			++ndo->ndo_Hflag;
1261 			break;
1262 
1263 		case 'i':
1264 			device = optarg;
1265 			break;
1266 
1267 #ifdef HAVE_PCAP_CREATE
1268 		case 'I':
1269 			++Iflag;
1270 			break;
1271 #endif /* HAVE_PCAP_CREATE */
1272 
1273 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
1274 		case 'j':
1275 			jflag = pcap_tstamp_type_name_to_val(optarg);
1276 			if (jflag < 0)
1277 				error("invalid time stamp type %s", optarg);
1278 			break;
1279 
1280 		case 'J':
1281 			Jflag++;
1282 			break;
1283 #endif
1284 
1285 		case 'l':
1286 #ifdef _WIN32
1287 			/*
1288 			 * _IOLBF is the same as _IOFBF in Microsoft's C
1289 			 * libraries; the only alternative they offer
1290 			 * is _IONBF.
1291 			 *
1292 			 * XXX - this should really be checking for MSVC++,
1293 			 * not _WIN32, if, for example, MinGW has its own
1294 			 * C library that is more UNIX-compatible.
1295 			 */
1296 			setvbuf(stdout, NULL, _IONBF, 0);
1297 #else /* _WIN32 */
1298 #ifdef HAVE_SETLINEBUF
1299 			setlinebuf(stdout);
1300 #else
1301 			setvbuf(stdout, NULL, _IOLBF, 0);
1302 #endif
1303 #endif /* _WIN32 */
1304 			break;
1305 
1306 		case 'K':
1307 			++ndo->ndo_Kflag;
1308 			break;
1309 
1310 		case 'm':
1311 			if (nd_have_smi_support()) {
1312 				if (nd_load_smi_module(optarg, ebuf, sizeof ebuf) == -1)
1313 					error("%s", ebuf);
1314 			} else {
1315 				(void)fprintf(stderr, "%s: ignoring option `-m %s' ",
1316 					      program_name, optarg);
1317 				(void)fprintf(stderr, "(no libsmi support)\n");
1318 			}
1319 			break;
1320 
1321 		case 'M':
1322 			/* TCP-MD5 shared secret */
1323 #ifndef HAVE_LIBCRYPTO
1324 			warning("crypto code not compiled in");
1325 #endif
1326 			ndo->ndo_sigsecret = optarg;
1327 			break;
1328 
1329 		case 'n':
1330 			++ndo->ndo_nflag;
1331 			break;
1332 
1333 		case 'N':
1334 			++ndo->ndo_Nflag;
1335 			break;
1336 
1337 		case 'O':
1338 			Oflag = 0;
1339 			break;
1340 
1341 		case 'p':
1342 			++pflag;
1343 			break;
1344 
1345 		case 'q':
1346 			++ndo->ndo_qflag;
1347 			++ndo->ndo_suppress_default_print;
1348 			break;
1349 
1350 #ifdef HAVE_PCAP_SETDIRECTION
1351 		case 'Q':
1352 			if (ascii_strcasecmp(optarg, "in") == 0)
1353 				Qflag = PCAP_D_IN;
1354 			else if (ascii_strcasecmp(optarg, "out") == 0)
1355 				Qflag = PCAP_D_OUT;
1356 			else if (ascii_strcasecmp(optarg, "inout") == 0)
1357 				Qflag = PCAP_D_INOUT;
1358 			else
1359 				error("unknown capture direction `%s'", optarg);
1360 			break;
1361 #endif /* HAVE_PCAP_SETDIRECTION */
1362 
1363 		case 'r':
1364 			RFileName = optarg;
1365 			break;
1366 
1367 		case 's':
1368 			ndo->ndo_snaplen = strtol(optarg, &end, 0);
1369 			if (optarg == end || *end != '\0'
1370 			    || ndo->ndo_snaplen < 0 || ndo->ndo_snaplen > MAXIMUM_SNAPLEN)
1371 				error("invalid snaplen %s", optarg);
1372 			else if (ndo->ndo_snaplen == 0)
1373 				ndo->ndo_snaplen = MAXIMUM_SNAPLEN;
1374 			break;
1375 
1376 		case 'S':
1377 			++ndo->ndo_Sflag;
1378 			break;
1379 
1380 		case 't':
1381 			++ndo->ndo_tflag;
1382 			break;
1383 
1384 		case 'T':
1385 			if (ascii_strcasecmp(optarg, "vat") == 0)
1386 				ndo->ndo_packettype = PT_VAT;
1387 			else if (ascii_strcasecmp(optarg, "wb") == 0)
1388 				ndo->ndo_packettype = PT_WB;
1389 			else if (ascii_strcasecmp(optarg, "rpc") == 0)
1390 				ndo->ndo_packettype = PT_RPC;
1391 			else if (ascii_strcasecmp(optarg, "rtp") == 0)
1392 				ndo->ndo_packettype = PT_RTP;
1393 			else if (ascii_strcasecmp(optarg, "rtcp") == 0)
1394 				ndo->ndo_packettype = PT_RTCP;
1395 			else if (ascii_strcasecmp(optarg, "snmp") == 0)
1396 				ndo->ndo_packettype = PT_SNMP;
1397 			else if (ascii_strcasecmp(optarg, "cnfp") == 0)
1398 				ndo->ndo_packettype = PT_CNFP;
1399 			else if (ascii_strcasecmp(optarg, "tftp") == 0)
1400 				ndo->ndo_packettype = PT_TFTP;
1401 			else if (ascii_strcasecmp(optarg, "aodv") == 0)
1402 				ndo->ndo_packettype = PT_AODV;
1403 			else if (ascii_strcasecmp(optarg, "carp") == 0)
1404 				ndo->ndo_packettype = PT_CARP;
1405 			else if (ascii_strcasecmp(optarg, "radius") == 0)
1406 				ndo->ndo_packettype = PT_RADIUS;
1407 			else if (ascii_strcasecmp(optarg, "zmtp1") == 0)
1408 				ndo->ndo_packettype = PT_ZMTP1;
1409 			else if (ascii_strcasecmp(optarg, "vxlan") == 0)
1410 				ndo->ndo_packettype = PT_VXLAN;
1411 			else if (ascii_strcasecmp(optarg, "pgm") == 0)
1412 				ndo->ndo_packettype = PT_PGM;
1413 			else if (ascii_strcasecmp(optarg, "pgm_zmtp1") == 0)
1414 				ndo->ndo_packettype = PT_PGM_ZMTP1;
1415 			else if (ascii_strcasecmp(optarg, "lmp") == 0)
1416 				ndo->ndo_packettype = PT_LMP;
1417 			else if (ascii_strcasecmp(optarg, "resp") == 0)
1418 				ndo->ndo_packettype = PT_RESP;
1419 			else
1420 				error("unknown packet type `%s'", optarg);
1421 			break;
1422 
1423 		case 'u':
1424 			++ndo->ndo_uflag;
1425 			break;
1426 
1427 #ifdef HAVE_PCAP_DUMP_FLUSH
1428 		case 'U':
1429 			++Uflag;
1430 			break;
1431 #endif
1432 
1433 		case 'v':
1434 			++ndo->ndo_vflag;
1435 			break;
1436 
1437 		case 'V':
1438 			VFileName = optarg;
1439 			break;
1440 
1441 		case 'w':
1442 			WFileName = optarg;
1443 			break;
1444 
1445 		case 'W':
1446 			Wflag = atoi(optarg);
1447 			if (Wflag <= 0)
1448 				error("invalid number of output files %s", optarg);
1449 			WflagChars = getWflagChars(Wflag);
1450 			break;
1451 
1452 		case 'x':
1453 			++ndo->ndo_xflag;
1454 			++ndo->ndo_suppress_default_print;
1455 			break;
1456 
1457 		case 'X':
1458 			++ndo->ndo_Xflag;
1459 			++ndo->ndo_suppress_default_print;
1460 			break;
1461 
1462 		case 'y':
1463 			yflag_dlt_name = optarg;
1464 			yflag_dlt =
1465 				pcap_datalink_name_to_val(yflag_dlt_name);
1466 			if (yflag_dlt < 0)
1467 				error("invalid data link type %s", yflag_dlt_name);
1468 			break;
1469 
1470 #ifdef HAVE_PCAP_SET_PARSER_DEBUG
1471 		case 'Y':
1472 			{
1473 			/* Undocumented flag */
1474 			pcap_set_parser_debug(1);
1475 			}
1476 			break;
1477 #endif
1478 		case 'z':
1479 			zflag = optarg;
1480 			break;
1481 
1482 		case 'Z':
1483 			username = optarg;
1484 			break;
1485 
1486 		case '#':
1487 			ndo->ndo_packet_number = 1;
1488 			break;
1489 
1490 		case OPTION_VERSION:
1491 			print_version();
1492 			exit_tcpdump(0);
1493 			break;
1494 
1495 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
1496 		case OPTION_TSTAMP_PRECISION:
1497 			ndo->ndo_tstamp_precision = tstamp_precision_from_string(optarg);
1498 			if (ndo->ndo_tstamp_precision < 0)
1499 				error("unsupported time stamp precision");
1500 			break;
1501 #endif
1502 
1503 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
1504 		case OPTION_IMMEDIATE_MODE:
1505 			immediate_mode = 1;
1506 			break;
1507 #endif
1508 
1509 		default:
1510 			print_usage();
1511 			exit_tcpdump(1);
1512 			/* NOTREACHED */
1513 		}
1514 
1515 #ifdef HAVE_PCAP_FINDALLDEVS
1516 	if (Dflag)
1517 		show_devices_and_exit();
1518 #endif
1519 
1520 	switch (ndo->ndo_tflag) {
1521 
1522 	case 0: /* Default */
1523 	case 4: /* Default + Date*/
1524 		timezone_offset = gmt2local(0);
1525 		break;
1526 
1527 	case 1: /* No time stamp */
1528 	case 2: /* Unix timeval style */
1529 	case 3: /* Microseconds since previous packet */
1530         case 5: /* Microseconds since first packet */
1531 		break;
1532 
1533 	default: /* Not supported */
1534 		error("only -t, -tt, -ttt, -tttt and -ttttt are supported");
1535 		break;
1536 	}
1537 
1538 	if (ndo->ndo_fflag != 0 && (VFileName != NULL || RFileName != NULL))
1539 		error("-f can not be used with -V or -r");
1540 
1541 	if (VFileName != NULL && RFileName != NULL)
1542 		error("-V and -r are mutually exclusive.");
1543 
1544 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
1545 	/*
1546 	 * If we're printing dissected packets to the standard output
1547 	 * rather than saving raw packets to a file, and the standard
1548 	 * output is a terminal, use immediate mode, as the user's
1549 	 * probably expecting to see packets pop up immediately.
1550 	 */
1551 	if (WFileName == NULL && isatty(1))
1552 		immediate_mode = 1;
1553 #endif
1554 
1555 #ifdef WITH_CHROOT
1556 	/* if run as root, prepare for chrooting */
1557 	if (getuid() == 0 || geteuid() == 0) {
1558 		/* future extensibility for cmd-line arguments */
1559 		if (!chroot_dir)
1560 			chroot_dir = WITH_CHROOT;
1561 	}
1562 #endif
1563 
1564 #ifdef WITH_USER
1565 	/* if run as root, prepare for dropping root privileges */
1566 	if (getuid() == 0 || geteuid() == 0) {
1567 		/* Run with '-Z root' to restore old behaviour */
1568 		if (!username)
1569 			username = WITH_USER;
1570 	}
1571 #endif
1572 
1573 	if (RFileName != NULL || VFileName != NULL) {
1574 		/*
1575 		 * If RFileName is non-null, it's the pathname of a
1576 		 * savefile to read.  If VFileName is non-null, it's
1577 		 * the pathname of a file containing a list of pathnames
1578 		 * (one per line) of savefiles to read.
1579 		 *
1580 		 * In either case, we're reading a savefile, not doing
1581 		 * a live capture.
1582 		 */
1583 #ifndef _WIN32
1584 		/*
1585 		 * We don't need network access, so relinquish any set-UID
1586 		 * or set-GID privileges we have (if any).
1587 		 *
1588 		 * We do *not* want set-UID privileges when opening a
1589 		 * trace file, as that might let the user read other
1590 		 * people's trace files (especially if we're set-UID
1591 		 * root).
1592 		 */
1593 		if (setgid(getgid()) != 0 || setuid(getuid()) != 0 )
1594 			fprintf(stderr, "Warning: setgid/setuid failed !\n");
1595 #endif /* _WIN32 */
1596 		if (VFileName != NULL) {
1597 			if (VFileName[0] == '-' && VFileName[1] == '\0')
1598 				VFile = stdin;
1599 			else
1600 				VFile = fopen(VFileName, "r");
1601 
1602 			if (VFile == NULL)
1603 				error("Unable to open file: %s\n", pcap_strerror(errno));
1604 
1605 			ret = get_next_file(VFile, VFileLine);
1606 			if (!ret)
1607 				error("Nothing in %s\n", VFileName);
1608 			RFileName = VFileLine;
1609 		}
1610 
1611 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
1612 		pd = pcap_open_offline_with_tstamp_precision(RFileName,
1613 		    ndo->ndo_tstamp_precision, ebuf);
1614 #else
1615 		pd = pcap_open_offline(RFileName, ebuf);
1616 #endif
1617 
1618 		if (pd == NULL)
1619 			error("%s", ebuf);
1620 #ifdef HAVE_CAPSICUM
1621 		cap_rights_init(&rights, CAP_READ);
1622 		if (cap_rights_limit(fileno(pcap_file(pd)), &rights) < 0 &&
1623 		    errno != ENOSYS) {
1624 			error("unable to limit pcap descriptor");
1625 		}
1626 #endif
1627 		dlt = pcap_datalink(pd);
1628 		dlt_name = pcap_datalink_val_to_name(dlt);
1629 		if (dlt_name == NULL) {
1630 			fprintf(stderr, "reading from file %s, link-type %u\n",
1631 			    RFileName, dlt);
1632 		} else {
1633 			fprintf(stderr,
1634 			    "reading from file %s, link-type %s (%s)\n",
1635 			    RFileName, dlt_name,
1636 			    pcap_datalink_val_to_description(dlt));
1637 		}
1638 	} else {
1639 		/*
1640 		 * We're doing a live capture.
1641 		 */
1642 		if (device == NULL) {
1643 			/*
1644 			 * No interface was specified.  Pick one.
1645 			 */
1646 #ifdef HAVE_PCAP_FINDALLDEVS
1647 			/*
1648 			 * Find the list of interfaces, and pick
1649 			 * the first interface.
1650 			 */
1651 			if (pcap_findalldevs(&devlist, ebuf) >= 0 &&
1652 			    devlist != NULL) {
1653 				device = strdup(devlist->name);
1654 				pcap_freealldevs(devlist);
1655 			}
1656 #else /* HAVE_PCAP_FINDALLDEVS */
1657 			/*
1658 			 * Use whatever interface pcap_lookupdev()
1659 			 * chooses.
1660 			 */
1661 			device = pcap_lookupdev(ebuf);
1662 #endif
1663 			if (device == NULL)
1664 				error("%s", ebuf);
1665 		}
1666 
1667 		/*
1668 		 * Try to open the interface with the specified name.
1669 		 */
1670 		pd = open_interface(device, ndo, ebuf);
1671 		if (pd == NULL) {
1672 			/*
1673 			 * That failed.  If we can get a list of
1674 			 * interfaces, and the interface name
1675 			 * is purely numeric, try to use it as
1676 			 * a 1-based index in the list of
1677 			 * interfaces.
1678 			 */
1679 #ifdef HAVE_PCAP_FINDALLDEVS
1680 			devnum = parse_interface_number(device);
1681 			if (devnum == -1) {
1682 				/*
1683 				 * It's not a number; just report
1684 				 * the open error and fail.
1685 				 */
1686 				error("%s", ebuf);
1687 			}
1688 
1689 			/*
1690 			 * OK, it's a number; try to find the
1691 			 * interface with that index, and try
1692 			 * to open it.
1693 			 *
1694 			 * find_interface_by_number() exits if it
1695 			 * couldn't be found.
1696 			 */
1697 			device = find_interface_by_number(devnum);
1698 			pd = open_interface(device, ndo, ebuf);
1699 			if (pd == NULL)
1700 				error("%s", ebuf);
1701 #else /* HAVE_PCAP_FINDALLDEVS */
1702 			/*
1703 			 * We can't get a list of interfaces; just
1704 			 * fail.
1705 			 */
1706 			error("%s", ebuf);
1707 #endif /* HAVE_PCAP_FINDALLDEVS */
1708 		}
1709 
1710 		/*
1711 		 * Let user own process after socket has been opened.
1712 		 */
1713 #ifndef _WIN32
1714 		if (setgid(getgid()) != 0 || setuid(getuid()) != 0)
1715 			fprintf(stderr, "Warning: setgid/setuid failed !\n");
1716 #endif /* _WIN32 */
1717 #if !defined(HAVE_PCAP_CREATE) && defined(_WIN32)
1718 		if(Bflag != 0)
1719 			if(pcap_setbuff(pd, Bflag)==-1){
1720 				error("%s", pcap_geterr(pd));
1721 			}
1722 #endif /* !defined(HAVE_PCAP_CREATE) && defined(_WIN32) */
1723 		if (Lflag)
1724 			show_dlts_and_exit(pd, device);
1725 		if (yflag_dlt >= 0) {
1726 #ifdef HAVE_PCAP_SET_DATALINK
1727 			if (pcap_set_datalink(pd, yflag_dlt) < 0)
1728 				error("%s", pcap_geterr(pd));
1729 #else
1730 			/*
1731 			 * We don't actually support changing the
1732 			 * data link type, so we only let them
1733 			 * set it to what it already is.
1734 			 */
1735 			if (yflag_dlt != pcap_datalink(pd)) {
1736 				error("%s is not one of the DLTs supported by this device\n",
1737 				      yflag_dlt_name);
1738 			}
1739 #endif
1740 			(void)fprintf(stderr, "%s: data link type %s\n",
1741 				      program_name, yflag_dlt_name);
1742 			(void)fflush(stderr);
1743 		}
1744 		i = pcap_snapshot(pd);
1745 		if (ndo->ndo_snaplen < i) {
1746 			warning("snaplen raised from %d to %d", ndo->ndo_snaplen, i);
1747 			ndo->ndo_snaplen = i;
1748 		}
1749                 if(ndo->ndo_fflag != 0) {
1750                         if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
1751                                 warning("foreign (-f) flag used but: %s", ebuf);
1752                         }
1753                 }
1754 
1755 	}
1756 	if (infile)
1757 		cmdbuf = read_infile(infile);
1758 	else
1759 		cmdbuf = copy_argv(&argv[optind]);
1760 
1761 #ifdef HAVE_PCAP_SET_OPTIMIZER_DEBUG
1762 	pcap_set_optimizer_debug(dflag);
1763 #endif
1764 	if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
1765 		error("%s", pcap_geterr(pd));
1766 	if (dflag) {
1767 		bpf_dump(&fcode, dflag);
1768 		pcap_close(pd);
1769 		free(cmdbuf);
1770 		pcap_freecode(&fcode);
1771 		exit_tcpdump(0);
1772 	}
1773 	init_print(ndo, localnet, netmask, timezone_offset);
1774 
1775 #ifndef _WIN32
1776 	(void)setsignal(SIGPIPE, cleanup);
1777 	(void)setsignal(SIGTERM, cleanup);
1778 	(void)setsignal(SIGINT, cleanup);
1779 #endif /* _WIN32 */
1780 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
1781 	(void)setsignal(SIGCHLD, child_cleanup);
1782 #endif
1783 	/* Cooperate with nohup(1) */
1784 #ifndef _WIN32
1785 	if ((oldhandler = setsignal(SIGHUP, cleanup)) != SIG_DFL)
1786 		(void)setsignal(SIGHUP, oldhandler);
1787 #endif /* _WIN32 */
1788 
1789 #ifndef _WIN32
1790 	/*
1791 	 * If a user name was specified with "-Z", attempt to switch to
1792 	 * that user's UID.  This would probably be used with sudo,
1793 	 * to allow tcpdump to be run in a special restricted
1794 	 * account (if you just want to allow users to open capture
1795 	 * devices, and can't just give users that permission,
1796 	 * you'd make tcpdump set-UID or set-GID).
1797 	 *
1798 	 * Tcpdump doesn't necessarily write only to one savefile;
1799 	 * the general only way to allow a -Z instance to write to
1800 	 * savefiles as the user under whose UID it's run, rather
1801 	 * than as the user specified with -Z, would thus be to switch
1802 	 * to the original user ID before opening a capture file and
1803 	 * then switch back to the -Z user ID after opening the savefile.
1804 	 * Switching to the -Z user ID only after opening the first
1805 	 * savefile doesn't handle the general case.
1806 	 */
1807 
1808 	if (getuid() == 0 || geteuid() == 0) {
1809 #ifdef HAVE_LIBCAP_NG
1810 		/* Initialize capng */
1811 		capng_clear(CAPNG_SELECT_BOTH);
1812 		if (username) {
1813 			capng_updatev(
1814 				CAPNG_ADD,
1815 				CAPNG_PERMITTED | CAPNG_EFFECTIVE,
1816 				CAP_SETUID,
1817 				CAP_SETGID,
1818 				-1);
1819 		}
1820 		if (chroot_dir) {
1821 			capng_update(
1822 				CAPNG_ADD,
1823 				CAPNG_PERMITTED | CAPNG_EFFECTIVE,
1824 				CAP_SYS_CHROOT
1825 				);
1826 		}
1827 
1828 		if (WFileName) {
1829 			capng_update(
1830 				CAPNG_ADD,
1831 				CAPNG_PERMITTED | CAPNG_EFFECTIVE,
1832 				CAP_DAC_OVERRIDE
1833 				);
1834 		}
1835 		capng_apply(CAPNG_SELECT_BOTH);
1836 #endif /* HAVE_LIBCAP_NG */
1837 		if (username || chroot_dir)
1838 			droproot(username, chroot_dir);
1839 
1840 	}
1841 #endif /* _WIN32 */
1842 
1843 	if (pcap_setfilter(pd, &fcode) < 0)
1844 		error("%s", pcap_geterr(pd));
1845 #ifdef HAVE_CAPSICUM
1846 	if (RFileName == NULL && VFileName == NULL) {
1847 		static const unsigned long cmds[] = { BIOCGSTATS, BIOCROTZBUF };
1848 
1849 		/*
1850 		 * The various libpcap devices use a combination of
1851 		 * read (bpf), ioctl (bpf, netmap), poll (netmap)
1852 		 * so we add the relevant access rights.
1853 		 */
1854 		cap_rights_init(&rights, CAP_IOCTL, CAP_READ, CAP_EVENT);
1855 		if (cap_rights_limit(pcap_fileno(pd), &rights) < 0 &&
1856 		    errno != ENOSYS) {
1857 			error("unable to limit pcap descriptor");
1858 		}
1859 		if (cap_ioctls_limit(pcap_fileno(pd), cmds,
1860 		    sizeof(cmds) / sizeof(cmds[0])) < 0 && errno != ENOSYS) {
1861 			error("unable to limit ioctls on pcap descriptor");
1862 		}
1863 	}
1864 #endif
1865 	if (WFileName) {
1866 		pcap_dumper_t *p;
1867 		/* Do not exceed the default PATH_MAX for files. */
1868 		dumpinfo.CurrentFileName = (char *)malloc(PATH_MAX + 1);
1869 
1870 		if (dumpinfo.CurrentFileName == NULL)
1871 			error("malloc of dumpinfo.CurrentFileName");
1872 
1873 		/* We do not need numbering for dumpfiles if Cflag isn't set. */
1874 		if (Cflag != 0)
1875 		  MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, WflagChars);
1876 		else
1877 		  MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, 0);
1878 
1879 		p = pcap_dump_open(pd, dumpinfo.CurrentFileName);
1880 #ifdef HAVE_LIBCAP_NG
1881 		/* Give up CAP_DAC_OVERRIDE capability.
1882 		 * Only allow it to be restored if the -C or -G flag have been
1883 		 * set since we may need to create more files later on.
1884 		 */
1885 		capng_update(
1886 			CAPNG_DROP,
1887 			(Cflag || Gflag ? 0 : CAPNG_PERMITTED)
1888 				| CAPNG_EFFECTIVE,
1889 			CAP_DAC_OVERRIDE
1890 			);
1891 		capng_apply(CAPNG_SELECT_BOTH);
1892 #endif /* HAVE_LIBCAP_NG */
1893 		if (p == NULL)
1894 			error("%s", pcap_geterr(pd));
1895 #ifdef HAVE_CAPSICUM
1896 		set_dumper_capsicum_rights(p);
1897 #endif
1898 		if (Cflag != 0 || Gflag != 0) {
1899 #ifdef HAVE_CAPSICUM
1900 			dumpinfo.WFileName = strdup(basename(WFileName));
1901 			if (dumpinfo.WFileName == NULL) {
1902 				error("Unable to allocate memory for file %s",
1903 				    WFileName);
1904 			}
1905 			dumpinfo.dirfd = open(dirname(WFileName),
1906 			    O_DIRECTORY | O_RDONLY);
1907 			if (dumpinfo.dirfd < 0) {
1908 				error("unable to open directory %s",
1909 				    dirname(WFileName));
1910 			}
1911 			cap_rights_init(&rights, CAP_CREATE, CAP_FCNTL,
1912 			    CAP_FTRUNCATE, CAP_LOOKUP, CAP_SEEK, CAP_WRITE);
1913 			if (cap_rights_limit(dumpinfo.dirfd, &rights) < 0 &&
1914 			    errno != ENOSYS) {
1915 				error("unable to limit directory rights");
1916 			}
1917 			if (cap_fcntls_limit(dumpinfo.dirfd, CAP_FCNTL_GETFL) < 0 &&
1918 			    errno != ENOSYS) {
1919 				error("unable to limit dump descriptor fcntls");
1920 			}
1921 #else	/* !HAVE_CAPSICUM */
1922 			dumpinfo.WFileName = WFileName;
1923 #endif
1924 			callback = dump_packet_and_trunc;
1925 			dumpinfo.pd = pd;
1926 			dumpinfo.p = p;
1927 			pcap_userdata = (u_char *)&dumpinfo;
1928 		} else {
1929 			callback = dump_packet;
1930 			pcap_userdata = (u_char *)p;
1931 		}
1932 #ifdef HAVE_PCAP_DUMP_FLUSH
1933 		if (Uflag)
1934 			pcap_dump_flush(p);
1935 #endif
1936 	} else {
1937 		dlt = pcap_datalink(pd);
1938 		ndo->ndo_if_printer = get_if_printer(ndo, dlt);
1939 		callback = print_packet;
1940 		pcap_userdata = (u_char *)ndo;
1941 	}
1942 
1943 #ifdef SIGNAL_REQ_INFO
1944 	/*
1945 	 * We can't get statistics when reading from a file rather
1946 	 * than capturing from a device.
1947 	 */
1948 	if (RFileName == NULL)
1949 		(void)setsignal(SIGNAL_REQ_INFO, requestinfo);
1950 #endif
1951 
1952 	if (ndo->ndo_vflag > 0 && WFileName) {
1953 		/*
1954 		 * When capturing to a file, "-v" means tcpdump should,
1955 		 * every 10 seconds, "v"erbosely report the number of
1956 		 * packets captured.
1957 		 */
1958 #ifdef USE_WIN32_MM_TIMER
1959 		/* call verbose_stats_dump() each 1000 +/-100msec */
1960 		timer_id = timeSetEvent(1000, 100, verbose_stats_dump, 0, TIME_PERIODIC);
1961 		setvbuf(stderr, NULL, _IONBF, 0);
1962 #elif defined(HAVE_ALARM)
1963 		(void)setsignal(SIGALRM, verbose_stats_dump);
1964 		alarm(1);
1965 #endif
1966 	}
1967 
1968 	if (RFileName == NULL) {
1969 		/*
1970 		 * Live capture (if -V was specified, we set RFileName
1971 		 * to a file from the -V file).  Print a message to
1972 		 * the standard error on UN*X.
1973 		 */
1974 		if (!ndo->ndo_vflag && !WFileName) {
1975 			(void)fprintf(stderr,
1976 			    "%s: verbose output suppressed, use -v or -vv for full protocol decode\n",
1977 			    program_name);
1978 		} else
1979 			(void)fprintf(stderr, "%s: ", program_name);
1980 		dlt = pcap_datalink(pd);
1981 		dlt_name = pcap_datalink_val_to_name(dlt);
1982 		if (dlt_name == NULL) {
1983 			(void)fprintf(stderr, "listening on %s, link-type %u, capture size %u bytes\n",
1984 			    device, dlt, ndo->ndo_snaplen);
1985 		} else {
1986 			(void)fprintf(stderr, "listening on %s, link-type %s (%s), capture size %u bytes\n",
1987 			    device, dlt_name,
1988 			    pcap_datalink_val_to_description(dlt), ndo->ndo_snaplen);
1989 		}
1990 		(void)fflush(stderr);
1991 	}
1992 
1993 #ifdef HAVE_CAPSICUM
1994 	cansandbox = (ndo->ndo_nflag && VFileName == NULL && zflag == NULL);
1995 	if (cansandbox && cap_enter() < 0 && errno != ENOSYS)
1996 		error("unable to enter the capability mode");
1997 #endif	/* HAVE_CAPSICUM */
1998 
1999 	do {
2000 		status = pcap_loop(pd, cnt, callback, pcap_userdata);
2001 		if (WFileName == NULL) {
2002 			/*
2003 			 * We're printing packets.  Flush the printed output,
2004 			 * so it doesn't get intermingled with error output.
2005 			 */
2006 			if (status == -2) {
2007 				/*
2008 				 * We got interrupted, so perhaps we didn't
2009 				 * manage to finish a line we were printing.
2010 				 * Print an extra newline, just in case.
2011 				 */
2012 				putchar('\n');
2013 			}
2014 			(void)fflush(stdout);
2015 		}
2016                 if (status == -2) {
2017 			/*
2018 			 * We got interrupted. If we are reading multiple
2019 			 * files (via -V) set these so that we stop.
2020 			 */
2021 			VFileName = NULL;
2022 			ret = NULL;
2023 		}
2024 		if (status == -1) {
2025 			/*
2026 			 * Error.  Report it.
2027 			 */
2028 			(void)fprintf(stderr, "%s: pcap_loop: %s\n",
2029 			    program_name, pcap_geterr(pd));
2030 		}
2031 		if (RFileName == NULL) {
2032 			/*
2033 			 * We're doing a live capture.  Report the capture
2034 			 * statistics.
2035 			 */
2036 			info(1);
2037 		}
2038 		pcap_close(pd);
2039 		if (VFileName != NULL) {
2040 			ret = get_next_file(VFile, VFileLine);
2041 			if (ret) {
2042 				int new_dlt;
2043 
2044 				RFileName = VFileLine;
2045 				pd = pcap_open_offline(RFileName, ebuf);
2046 				if (pd == NULL)
2047 					error("%s", ebuf);
2048 #ifdef HAVE_CAPSICUM
2049 				cap_rights_init(&rights, CAP_READ);
2050 				if (cap_rights_limit(fileno(pcap_file(pd)),
2051 				    &rights) < 0 && errno != ENOSYS) {
2052 					error("unable to limit pcap descriptor");
2053 				}
2054 #endif
2055 				new_dlt = pcap_datalink(pd);
2056 				if (new_dlt != dlt) {
2057 					/*
2058 					 * The new file has a different
2059 					 * link-layer header type from the
2060 					 * previous one.
2061 					 */
2062 					if (WFileName != NULL) {
2063 						/*
2064 						 * We're writing raw packets
2065 						 * that match the filter to
2066 						 * a pcap file.  pcap files
2067 						 * don't support multiple
2068 						 * different link-layer
2069 						 * header types, so we fail
2070 						 * here.
2071 						 */
2072 						error("%s: new dlt does not match original", RFileName);
2073 					}
2074 
2075 					/*
2076 					 * We're printing the decoded packets;
2077 					 * switch to the new DLT.
2078 					 *
2079 					 * To do that, we need to change
2080 					 * the printer, change the DLT name,
2081 					 * and recompile the filter with
2082 					 * the new DLT.
2083 					 */
2084 					dlt = new_dlt;
2085 					ndo->ndo_if_printer = get_if_printer(ndo, dlt);
2086 					if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
2087 						error("%s", pcap_geterr(pd));
2088 				}
2089 
2090 				/*
2091 				 * Set the filter on the new file.
2092 				 */
2093 				if (pcap_setfilter(pd, &fcode) < 0)
2094 					error("%s", pcap_geterr(pd));
2095 
2096 				/*
2097 				 * Report the new file.
2098 				 */
2099 				dlt_name = pcap_datalink_val_to_name(dlt);
2100 				if (dlt_name == NULL) {
2101 					fprintf(stderr, "reading from file %s, link-type %u\n",
2102 					    RFileName, dlt);
2103 				} else {
2104 					fprintf(stderr,
2105 					"reading from file %s, link-type %s (%s)\n",
2106 					    RFileName, dlt_name,
2107 					    pcap_datalink_val_to_description(dlt));
2108 				}
2109 			}
2110 		}
2111 	}
2112 	while (ret != NULL);
2113 
2114 	free(cmdbuf);
2115 	pcap_freecode(&fcode);
2116 	exit_tcpdump(status == -1 ? 1 : 0);
2117 }
2118 
2119 /* make a clean exit on interrupts */
2120 static RETSIGTYPE
cleanup(int signo _U_)2121 cleanup(int signo _U_)
2122 {
2123 #ifdef USE_WIN32_MM_TIMER
2124 	if (timer_id)
2125 		timeKillEvent(timer_id);
2126 	timer_id = 0;
2127 #elif defined(HAVE_ALARM)
2128 	alarm(0);
2129 #endif
2130 
2131 #ifdef HAVE_PCAP_BREAKLOOP
2132 	/*
2133 	 * We have "pcap_breakloop()"; use it, so that we do as little
2134 	 * as possible in the signal handler (it's probably not safe
2135 	 * to do anything with standard I/O streams in a signal handler -
2136 	 * the ANSI C standard doesn't say it is).
2137 	 */
2138 	pcap_breakloop(pd);
2139 #else
2140 	/*
2141 	 * We don't have "pcap_breakloop()"; this isn't safe, but
2142 	 * it's the best we can do.  Print the summary if we're
2143 	 * not reading from a savefile - i.e., if we're doing a
2144 	 * live capture - and exit.
2145 	 */
2146 	if (pd != NULL && pcap_file(pd) == NULL) {
2147 		/*
2148 		 * We got interrupted, so perhaps we didn't
2149 		 * manage to finish a line we were printing.
2150 		 * Print an extra newline, just in case.
2151 		 */
2152 		putchar('\n');
2153 		(void)fflush(stdout);
2154 		info(1);
2155 	}
2156 	exit_tcpdump(0);
2157 #endif
2158 }
2159 
2160 /*
2161   On windows, we do not use a fork, so we do not care less about
2162   waiting a child processes to die
2163  */
2164 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
2165 static RETSIGTYPE
child_cleanup(int signo _U_)2166 child_cleanup(int signo _U_)
2167 {
2168   wait(NULL);
2169 }
2170 #endif /* HAVE_FORK && HAVE_VFORK */
2171 
2172 static void
info(register int verbose)2173 info(register int verbose)
2174 {
2175 	struct pcap_stat stats;
2176 
2177 	/*
2178 	 * Older versions of libpcap didn't set ps_ifdrop on some
2179 	 * platforms; initialize it to 0 to handle that.
2180 	 */
2181 	stats.ps_ifdrop = 0;
2182 	if (pcap_stats(pd, &stats) < 0) {
2183 		(void)fprintf(stderr, "pcap_stats: %s\n", pcap_geterr(pd));
2184 		infoprint = 0;
2185 		return;
2186 	}
2187 
2188 	if (!verbose)
2189 		fprintf(stderr, "%s: ", program_name);
2190 
2191 	(void)fprintf(stderr, "%u packet%s captured", packets_captured,
2192 	    PLURAL_SUFFIX(packets_captured));
2193 	if (!verbose)
2194 		fputs(", ", stderr);
2195 	else
2196 		putc('\n', stderr);
2197 	(void)fprintf(stderr, "%u packet%s received by filter", stats.ps_recv,
2198 	    PLURAL_SUFFIX(stats.ps_recv));
2199 	if (!verbose)
2200 		fputs(", ", stderr);
2201 	else
2202 		putc('\n', stderr);
2203 	(void)fprintf(stderr, "%u packet%s dropped by kernel", stats.ps_drop,
2204 	    PLURAL_SUFFIX(stats.ps_drop));
2205 	if (stats.ps_ifdrop != 0) {
2206 		if (!verbose)
2207 			fputs(", ", stderr);
2208 		else
2209 			putc('\n', stderr);
2210 		(void)fprintf(stderr, "%u packet%s dropped by interface\n",
2211 		    stats.ps_ifdrop, PLURAL_SUFFIX(stats.ps_ifdrop));
2212 	} else
2213 		putc('\n', stderr);
2214 	infoprint = 0;
2215 }
2216 
2217 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
2218 #ifdef HAVE_FORK
2219 #define fork_subprocess() fork()
2220 #else
2221 #define fork_subprocess() vfork()
2222 #endif
2223 static void
compress_savefile(const char * filename)2224 compress_savefile(const char *filename)
2225 {
2226 	pid_t child;
2227 
2228 	child = fork_subprocess();
2229 	if (child == -1) {
2230 		fprintf(stderr,
2231 			"compress_savefile: fork failed: %s\n",
2232 			pcap_strerror(errno));
2233 		return;
2234 	}
2235 	if (child != 0) {
2236 		/* Parent process. */
2237 		return;
2238 	}
2239 
2240 	/*
2241 	 * Child process.
2242 	 * Set to lowest priority so that this doesn't disturb the capture.
2243 	 */
2244 #ifdef NZERO
2245 	setpriority(PRIO_PROCESS, 0, NZERO - 1);
2246 #else
2247 	setpriority(PRIO_PROCESS, 0, 19);
2248 #endif
2249 	if (execlp(zflag, zflag, filename, (char *)NULL) == -1)
2250 		fprintf(stderr,
2251 			"compress_savefile: execlp(%s, %s) failed: %s\n",
2252 			zflag,
2253 			filename,
2254 			pcap_strerror(errno));
2255 #ifdef HAVE_FORK
2256 	exit(1);
2257 #else
2258 	_exit(1);
2259 #endif
2260 }
2261 #else  /* HAVE_FORK && HAVE_VFORK */
2262 static void
compress_savefile(const char * filename)2263 compress_savefile(const char *filename)
2264 {
2265 	fprintf(stderr,
2266 		"compress_savefile failed. Functionality not implemented under your system\n");
2267 }
2268 #endif /* HAVE_FORK && HAVE_VFORK */
2269 
2270 static void
dump_packet_and_trunc(u_char * user,const struct pcap_pkthdr * h,const u_char * sp)2271 dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
2272 {
2273 	struct dump_info *dump_info;
2274 
2275 	++packets_captured;
2276 
2277 	++infodelay;
2278 
2279 	dump_info = (struct dump_info *)user;
2280 
2281 	/*
2282 	 * XXX - this won't force the file to rotate on the specified time
2283 	 * boundary, but it will rotate on the first packet received after the
2284 	 * specified Gflag number of seconds. Note: if a Gflag time boundary
2285 	 * and a Cflag size boundary coincide, the time rotation will occur
2286 	 * first thereby cancelling the Cflag boundary (since the file should
2287 	 * be 0).
2288 	 */
2289 	if (Gflag != 0) {
2290 		/* Check if it is time to rotate */
2291 		time_t t;
2292 
2293 		/* Get the current time */
2294 		if ((t = time(NULL)) == (time_t)-1) {
2295 			error("dump_and_trunc_packet: can't get current_time: %s",
2296 			    pcap_strerror(errno));
2297 		}
2298 
2299 
2300 		/* If the time is greater than the specified window, rotate */
2301 		if (t - Gflag_time >= Gflag) {
2302 #ifdef HAVE_CAPSICUM
2303 			FILE *fp;
2304 			int fd;
2305 #endif
2306 
2307 			/* Update the Gflag_time */
2308 			Gflag_time = t;
2309 			/* Update Gflag_count */
2310 			Gflag_count++;
2311 			/*
2312 			 * Close the current file and open a new one.
2313 			 */
2314 			pcap_dump_close(dump_info->p);
2315 
2316 			/*
2317 			 * Compress the file we just closed, if the user asked for it
2318 			 */
2319 			if (zflag != NULL)
2320 				compress_savefile(dump_info->CurrentFileName);
2321 
2322 			/*
2323 			 * Check to see if we've exceeded the Wflag (when
2324 			 * not using Cflag).
2325 			 */
2326 			if (Cflag == 0 && Wflag > 0 && Gflag_count >= Wflag) {
2327 				(void)fprintf(stderr, "Maximum file limit reached: %d\n",
2328 				    Wflag);
2329 				info(1);
2330 				exit_tcpdump(0);
2331 				/* NOTREACHED */
2332 			}
2333 			if (dump_info->CurrentFileName != NULL)
2334 				free(dump_info->CurrentFileName);
2335 			/* Allocate space for max filename + \0. */
2336 			dump_info->CurrentFileName = (char *)malloc(PATH_MAX + 1);
2337 			if (dump_info->CurrentFileName == NULL)
2338 				error("dump_packet_and_trunc: malloc");
2339 			/*
2340 			 * Gflag was set otherwise we wouldn't be here. Reset the count
2341 			 * so multiple files would end with 1,2,3 in the filename.
2342 			 * The counting is handled with the -C flow after this.
2343 			 */
2344 			Cflag_count = 0;
2345 
2346 			/*
2347 			 * This is always the first file in the Cflag
2348 			 * rotation: e.g. 0
2349 			 * We also don't need numbering if Cflag is not set.
2350 			 */
2351 			if (Cflag != 0)
2352 				MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0,
2353 				    WflagChars);
2354 			else
2355 				MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0, 0);
2356 
2357 #ifdef HAVE_LIBCAP_NG
2358 			capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
2359 			capng_apply(CAPNG_SELECT_BOTH);
2360 #endif /* HAVE_LIBCAP_NG */
2361 #ifdef HAVE_CAPSICUM
2362 			fd = openat(dump_info->dirfd,
2363 			    dump_info->CurrentFileName,
2364 			    O_CREAT | O_WRONLY | O_TRUNC, 0644);
2365 			if (fd < 0) {
2366 				error("unable to open file %s",
2367 				    dump_info->CurrentFileName);
2368 			}
2369 			fp = fdopen(fd, "w");
2370 			if (fp == NULL) {
2371 				error("unable to fdopen file %s",
2372 				    dump_info->CurrentFileName);
2373 			}
2374 			dump_info->p = pcap_dump_fopen(dump_info->pd, fp);
2375 #else	/* !HAVE_CAPSICUM */
2376 			dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
2377 #endif
2378 #ifdef HAVE_LIBCAP_NG
2379 			capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
2380 			capng_apply(CAPNG_SELECT_BOTH);
2381 #endif /* HAVE_LIBCAP_NG */
2382 			if (dump_info->p == NULL)
2383 				error("%s", pcap_geterr(pd));
2384 #ifdef HAVE_CAPSICUM
2385 			set_dumper_capsicum_rights(dump_info->p);
2386 #endif
2387 		}
2388 	}
2389 
2390 	/*
2391 	 * XXX - this won't prevent capture files from getting
2392 	 * larger than Cflag - the last packet written to the
2393 	 * file could put it over Cflag.
2394 	 */
2395 	if (Cflag != 0) {
2396 		long size = pcap_dump_ftell(dump_info->p);
2397 
2398 		if (size == -1)
2399 			error("ftell fails on output file");
2400 		if (size > Cflag) {
2401 #ifdef HAVE_CAPSICUM
2402 			FILE *fp;
2403 			int fd;
2404 #endif
2405 
2406 			/*
2407 			 * Close the current file and open a new one.
2408 			 */
2409 			pcap_dump_close(dump_info->p);
2410 
2411 			/*
2412 			 * Compress the file we just closed, if the user
2413 			 * asked for it.
2414 			 */
2415 			if (zflag != NULL)
2416 				compress_savefile(dump_info->CurrentFileName);
2417 
2418 			Cflag_count++;
2419 			if (Wflag > 0) {
2420 				if (Cflag_count >= Wflag)
2421 					Cflag_count = 0;
2422 			}
2423 			if (dump_info->CurrentFileName != NULL)
2424 				free(dump_info->CurrentFileName);
2425 			dump_info->CurrentFileName = (char *)malloc(PATH_MAX + 1);
2426 			if (dump_info->CurrentFileName == NULL)
2427 				error("dump_packet_and_trunc: malloc");
2428 			MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, Cflag_count, WflagChars);
2429 #ifdef HAVE_LIBCAP_NG
2430 			capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
2431 			capng_apply(CAPNG_SELECT_BOTH);
2432 #endif /* HAVE_LIBCAP_NG */
2433 #ifdef HAVE_CAPSICUM
2434 			fd = openat(dump_info->dirfd, dump_info->CurrentFileName,
2435 			    O_CREAT | O_WRONLY | O_TRUNC, 0644);
2436 			if (fd < 0) {
2437 				error("unable to open file %s",
2438 				    dump_info->CurrentFileName);
2439 			}
2440 			fp = fdopen(fd, "w");
2441 			if (fp == NULL) {
2442 				error("unable to fdopen file %s",
2443 				    dump_info->CurrentFileName);
2444 			}
2445 			dump_info->p = pcap_dump_fopen(dump_info->pd, fp);
2446 #else	/* !HAVE_CAPSICUM */
2447 			dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
2448 #endif
2449 #ifdef HAVE_LIBCAP_NG
2450 			capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
2451 			capng_apply(CAPNG_SELECT_BOTH);
2452 #endif /* HAVE_LIBCAP_NG */
2453 			if (dump_info->p == NULL)
2454 				error("%s", pcap_geterr(pd));
2455 #ifdef HAVE_CAPSICUM
2456 			set_dumper_capsicum_rights(dump_info->p);
2457 #endif
2458 		}
2459 	}
2460 
2461 	pcap_dump((u_char *)dump_info->p, h, sp);
2462 #ifdef HAVE_PCAP_DUMP_FLUSH
2463 	if (Uflag)
2464 		pcap_dump_flush(dump_info->p);
2465 #endif
2466 
2467 	--infodelay;
2468 	if (infoprint)
2469 		info(0);
2470 }
2471 
2472 static void
dump_packet(u_char * user,const struct pcap_pkthdr * h,const u_char * sp)2473 dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
2474 {
2475 	++packets_captured;
2476 
2477 	++infodelay;
2478 
2479 	pcap_dump(user, h, sp);
2480 #ifdef HAVE_PCAP_DUMP_FLUSH
2481 	if (Uflag)
2482 		pcap_dump_flush((pcap_dumper_t *)user);
2483 #endif
2484 
2485 	--infodelay;
2486 	if (infoprint)
2487 		info(0);
2488 }
2489 
2490 static void
print_packet(u_char * user,const struct pcap_pkthdr * h,const u_char * sp)2491 print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
2492 {
2493 	++packets_captured;
2494 
2495 	++infodelay;
2496 
2497 	pretty_print_packet((netdissect_options *)user, h, sp, packets_captured);
2498 
2499 	--infodelay;
2500 	if (infoprint)
2501 		info(0);
2502 }
2503 
2504 #ifdef _WIN32
2505 	/*
2506 	 * XXX - there should really be libpcap calls to get the version
2507 	 * number as a string (the string would be generated from #defines
2508 	 * at run time, so that it's not generated from string constants
2509 	 * in the library, as, on many UNIX systems, those constants would
2510 	 * be statically linked into the application executable image, and
2511 	 * would thus reflect the version of libpcap on the system on
2512 	 * which the application was *linked*, not the system on which it's
2513 	 * *running*.
2514 	 *
2515 	 * That routine should be documented, unlike the "version[]"
2516 	 * string, so that UNIX vendors providing their own libpcaps
2517 	 * don't omit it (as a couple of vendors have...).
2518 	 *
2519 	 * Packet.dll should perhaps also export a routine to return the
2520 	 * version number of the Packet.dll code, to supply the
2521 	 * "Wpcap_version" information on Windows.
2522 	 */
2523 	char WDversion[]="current-git.tcpdump.org";
2524 #if !defined(HAVE_GENERATED_VERSION)
2525 	char version[]="current-git.tcpdump.org";
2526 #endif
2527 	char pcap_version[]="current-git.tcpdump.org";
2528 	char Wpcap_version[]="3.1";
2529 #endif
2530 
2531 #ifdef SIGNAL_REQ_INFO
requestinfo(int signo _U_)2532 RETSIGTYPE requestinfo(int signo _U_)
2533 {
2534 	if (infodelay)
2535 		++infoprint;
2536 	else
2537 		info(0);
2538 }
2539 #endif
2540 
2541 /*
2542  * Called once each second in verbose mode while dumping to file
2543  */
2544 #ifdef USE_WIN32_MM_TIMER
verbose_stats_dump(UINT timer_id _U_,UINT msg _U_,DWORD_PTR arg _U_,DWORD_PTR dw1 _U_,DWORD_PTR dw2 _U_)2545 void CALLBACK verbose_stats_dump (UINT timer_id _U_, UINT msg _U_, DWORD_PTR arg _U_,
2546 				  DWORD_PTR dw1 _U_, DWORD_PTR dw2 _U_)
2547 {
2548 	if (infodelay == 0)
2549 		fprintf(stderr, "Got %u\r", packets_captured);
2550 }
2551 #elif defined(HAVE_ALARM)
verbose_stats_dump(int sig _U_)2552 static void verbose_stats_dump(int sig _U_)
2553 {
2554 	if (infodelay == 0)
2555 		fprintf(stderr, "Got %u\r", packets_captured);
2556 	alarm(1);
2557 }
2558 #endif
2559 
2560 USES_APPLE_DEPRECATED_API
2561 static void
print_version(void)2562 print_version(void)
2563 {
2564 	extern char version[];
2565 #ifndef HAVE_PCAP_LIB_VERSION
2566 #if defined(_WIN32) || defined(HAVE_PCAP_VERSION)
2567 	extern char pcap_version[];
2568 #else /* defined(_WIN32) || defined(HAVE_PCAP_VERSION) */
2569 	static char pcap_version[] = "unknown";
2570 #endif /* defined(_WIN32) || defined(HAVE_PCAP_VERSION) */
2571 #endif /* HAVE_PCAP_LIB_VERSION */
2572 	const char *smi_version_string;
2573 
2574 #ifdef HAVE_PCAP_LIB_VERSION
2575 #ifdef _WIN32
2576 	(void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
2577 #else /* _WIN32 */
2578 	(void)fprintf(stderr, "%s version %s\n", program_name, version);
2579 #endif /* _WIN32 */
2580 	(void)fprintf(stderr, "%s\n",pcap_lib_version());
2581 #else /* HAVE_PCAP_LIB_VERSION */
2582 #ifdef _WIN32
2583 	(void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
2584 	(void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version);
2585 #else /* _WIN32 */
2586 	(void)fprintf(stderr, "%s version %s\n", program_name, version);
2587 	(void)fprintf(stderr, "libpcap version %s\n", pcap_version);
2588 #endif /* _WIN32 */
2589 #endif /* HAVE_PCAP_LIB_VERSION */
2590 
2591 #if defined(HAVE_LIBCRYPTO) && defined(SSLEAY_VERSION)
2592 	(void)fprintf (stderr, "%s\n", SSLeay_version(SSLEAY_VERSION));
2593 #endif
2594 
2595 	smi_version_string = nd_smi_version_string();
2596 	if (smi_version_string != NULL)
2597 		(void)fprintf (stderr, "SMI-library: %s\n", smi_version_string);
2598 
2599 #if defined(__SANITIZE_ADDRESS__)
2600 	(void)fprintf (stderr, "Compiled with AddressSanitizer/GCC.\n");
2601 #elif defined(__has_feature)
2602 #  if __has_feature(address_sanitizer)
2603 	(void)fprintf (stderr, "Compiled with AddressSanitizer/CLang.\n");
2604 #  endif
2605 #endif /* __SANITIZE_ADDRESS__ or __has_feature */
2606 }
2607 USES_APPLE_RST
2608 
2609 static void
print_usage(void)2610 print_usage(void)
2611 {
2612 	print_version();
2613 	(void)fprintf(stderr,
2614 "Usage: %s [-aAbd" D_FLAG "efhH" I_FLAG J_FLAG "KlLnNOpqStu" U_FLAG "vxX#]" B_FLAG_USAGE " [ -c count ]\n", program_name);
2615 	(void)fprintf(stderr,
2616 "\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n");
2617 	(void)fprintf(stderr,
2618 "\t\t[ -i interface ]" j_FLAG_USAGE " [ -M secret ] [ --number ]\n");
2619 #ifdef HAVE_PCAP_SETDIRECTION
2620 	(void)fprintf(stderr,
2621 "\t\t[ -Q in|out|inout ]\n");
2622 #endif
2623 	(void)fprintf(stderr,
2624 "\t\t[ -r file ] [ -s snaplen ] ");
2625 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
2626 	(void)fprintf(stderr, "[ --time-stamp-precision precision ]\n");
2627 	(void)fprintf(stderr,
2628 "\t\t");
2629 #endif
2630 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
2631 	(void)fprintf(stderr, "[ --immediate-mode ] ");
2632 #endif
2633 	(void)fprintf(stderr, "[ -T type ] [ --version ] [ -V file ]\n");
2634 	(void)fprintf(stderr,
2635 "\t\t[ -w file ] [ -W filecount ] [ -y datalinktype ] [ -z postrotate-command ]\n");
2636 	(void)fprintf(stderr,
2637 "\t\t[ -Z user ] [ expression ]\n");
2638 }
2639 /*
2640  * Local Variables:
2641  * c-style: whitesmith
2642  * c-basic-offset: 8
2643  * End:
2644  */
2645