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.
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
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.
21 * Support for splitting captures into multiple files with a maximum
25 * Seth Webster <swebster@sst.ll.mit.edu>
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";
35 * tcpdump - dump traffic on a network
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.
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().
51 #ifdef HAVE_PCAP_FINDALLDEVS
52 #ifndef HAVE_PCAP_IF_T
53 #undef HAVE_PCAP_FINDALLDEVS
57 #include <netdissect-stdinc.h>
61 #define _WINSOCKAPI_ /* Prevent inclusion of winsock.h in windows.h */
62 #endif /* _WINSOCKAPI_ */
75 #include <openssl/crypto.h>
78 #ifdef HAVE_GETOPT_LONG
81 #include "getopt_long.h"
83 /* Capsicum-specific code requires macros from <net/bpf.h>, which will fail
84 * to compile if <pcap.h> has already been included; including the headers
85 * in the opposite order works fine.
88 #include <sys/capability.h>
89 #include <sys/ioccom.h>
93 #endif /* HAVE_CAPSICUM */
101 #include <sys/wait.h>
102 #include <sys/resource.h>
107 /* capabilities convenience library */
108 /* If a code depends on HAVE_LIBCAP_NG, it depends also on HAVE_CAP_NG_H.
109 * If HAVE_CAP_NG_H is not defined, undefine HAVE_LIBCAP_NG.
110 * Thus, the later tests are done only on HAVE_LIBCAP_NG.
112 #ifdef HAVE_LIBCAP_NG
116 #undef HAVE_LIBCAP_NG
117 #endif /* HAVE_CAP_NG_H */
118 #endif /* HAVE_LIBCAP_NG */
120 #include "netdissect.h"
121 #include "interface.h"
122 #include "addrtoname.h"
124 #include "setsignal.h"
125 #include "gmt2local.h"
126 #include "pcap-missing.h"
127 #include "ascii_strcasecmp.h"
132 #define PATH_MAX 1024
136 #define SIGNAL_REQ_INFO SIGINFO
138 #define SIGNAL_REQ_INFO SIGUSR1
141 static int Cflag
; /* rotate dump files after this many bytes */
142 static int Cflag_count
; /* Keep track of which file number we're writing */
143 static int Dflag
; /* list available devices and exit */
144 static int dflag
; /* print filter code */
145 static int Gflag
; /* rotate dump files after this many seconds */
146 static int Gflag_count
; /* number of files created with Gflag rotation */
147 static time_t Gflag_time
; /* The last time_t the dump file was rotated. */
148 static int Lflag
; /* list available data link types and exit */
149 static int Iflag
; /* rfmon (monitor) mode */
150 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
151 static int Jflag
; /* list available time stamp types */
153 #ifdef HAVE_PCAP_SETDIRECTION
154 int Qflag
= -1; /* restrict captured packet by send/receive direction */
156 static int Uflag
; /* "unbuffered" output of dump files */
157 static int Wflag
; /* recycle output files after this number of files */
158 static int WflagChars
;
159 static char *zflag
= NULL
; /* compress each savefile using a specified command (like gzip or bzip2) */
161 static int infodelay
;
162 static int infoprint
;
167 static RETSIGTYPE
cleanup(int);
168 static RETSIGTYPE
child_cleanup(int);
169 static void print_version(void);
170 static void print_usage(void);
171 static void show_tstamp_types_and_exit(const char *device
) __attribute__((noreturn
));
172 static void show_dlts_and_exit(const char *device
) __attribute__((noreturn
));
174 static void print_packet(u_char
*, const struct pcap_pkthdr
*, const u_char
*);
175 static void dump_packet_and_trunc(u_char
*, const struct pcap_pkthdr
*, const u_char
*);
176 static void dump_packet(u_char
*, const struct pcap_pkthdr
*, const u_char
*);
177 static void droproot(const char *, const char *);
179 #ifdef SIGNAL_REQ_INFO
180 RETSIGTYPE
requestinfo(int);
183 #if defined(USE_WIN32_MM_TIMER)
184 #include <MMsystem.h>
185 static UINT timer_id
;
186 static void CALLBACK
verbose_stats_dump(UINT
, UINT
, DWORD_PTR
, DWORD_PTR
, DWORD_PTR
);
187 #elif defined(HAVE_ALARM)
188 static void verbose_stats_dump(int sig
);
191 static void info(int);
192 static u_int packets_captured
;
194 static const struct tok status_flags
[] = {
196 { PCAP_IF_UP
, "Up" },
198 #ifdef PCAP_IF_RUNNING
199 { PCAP_IF_RUNNING
, "Running" },
201 { PCAP_IF_LOOPBACK
, "Loopback" },
207 static int supports_monitor_mode
;
215 char *CurrentFileName
;
223 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
225 show_tstamp_types_and_exit(const char *device
)
228 int *tstamp_types
= 0;
229 const char *tstamp_type_name
;
232 n_tstamp_types
= pcap_list_tstamp_types(pd
, &tstamp_types
);
233 if (n_tstamp_types
< 0)
234 error("%s", pcap_geterr(pd
));
236 if (n_tstamp_types
== 0) {
237 fprintf(stderr
, "Time stamp type cannot be set for %s\n",
241 fprintf(stderr
, "Time stamp types for %s (use option -j to set):\n",
243 for (i
= 0; i
< n_tstamp_types
; i
++) {
244 tstamp_type_name
= pcap_tstamp_type_val_to_name(tstamp_types
[i
]);
245 if (tstamp_type_name
!= NULL
) {
246 (void) fprintf(stderr
, " %s (%s)\n", tstamp_type_name
,
247 pcap_tstamp_type_val_to_description(tstamp_types
[i
]));
249 (void) fprintf(stderr
, " %d\n", tstamp_types
[i
]);
252 pcap_free_tstamp_types(tstamp_types
);
258 show_dlts_and_exit(const char *device
)
262 const char *dlt_name
;
264 n_dlts
= pcap_list_datalinks(pd
, &dlts
);
266 error("%s", pcap_geterr(pd
));
267 else if (n_dlts
== 0 || !dlts
)
268 error("No data link types.");
271 * If the interface is known to support monitor mode, indicate
272 * whether these are the data link types available when not in
273 * monitor mode, if -I wasn't specified, or when in monitor mode,
274 * when -I was specified (the link-layer types available in
275 * monitor mode might be different from the ones available when
276 * not in monitor mode).
278 if (supports_monitor_mode
)
279 (void) fprintf(stderr
, "Data link types for %s %s (use option -y to set):\n",
281 Iflag
? "when in monitor mode" : "when not in monitor mode");
283 (void) fprintf(stderr
, "Data link types for %s (use option -y to set):\n",
286 for (i
= 0; i
< n_dlts
; i
++) {
287 dlt_name
= pcap_datalink_val_to_name(dlts
[i
]);
288 if (dlt_name
!= NULL
) {
289 (void) fprintf(stderr
, " %s (%s)", dlt_name
,
290 pcap_datalink_val_to_description(dlts
[i
]));
293 * OK, does tcpdump handle that type?
295 if (!has_printer(dlts
[i
]))
296 (void) fprintf(stderr
, " (printing not supported)");
297 fprintf(stderr
, "\n");
299 (void) fprintf(stderr
, " DLT %d (printing not supported)\n",
303 #ifdef HAVE_PCAP_FREE_DATALINKS
304 pcap_free_datalinks(dlts
);
309 #ifdef HAVE_PCAP_FINDALLDEVS
311 show_devices_and_exit (void)
313 pcap_if_t
*devpointer
;
314 char ebuf
[PCAP_ERRBUF_SIZE
];
317 if (pcap_findalldevs(&devpointer
, ebuf
) < 0)
320 for (i
= 0; devpointer
!= NULL
; i
++) {
321 printf("%d.%s", i
+1, devpointer
->name
);
322 if (devpointer
->description
!= NULL
)
323 printf(" (%s)", devpointer
->description
);
324 if (devpointer
->flags
!= 0)
325 printf(" [%s]", bittok2str(status_flags
, "none", devpointer
->flags
));
327 devpointer
= devpointer
->next
;
332 #endif /* HAVE_PCAP_FINDALLDEVS */
337 * Note that there we use all letters for short options except for g, k,
338 * o, and P, and those are used by other versions of tcpdump, and we should
339 * only use them for the same purposes that the other versions of tcpdump
342 * OS X tcpdump uses -g to force non--v output for IP to be on one
343 * line, making it more "g"repable;
345 * OS X tcpdump uses -k tospecify that packet comments in pcap-ng files
348 * OpenBSD tcpdump uses -o to indicate that OS fingerprinting should be done
349 * for hosts sending TCP SYN packets;
351 * OS X tcpdump uses -P to indicate that -w should write pcap-ng rather
354 * OS X tcpdump also uses -Q to specify expressions that match packet
355 * metadata, including but not limited to the packet direction.
356 * The expression syntax is different from a simple "in|out|inout",
357 * and those expressions aren't accepted by OS X tcpdump, but the
358 * equivalents would be "in" = "dir=in", "out" = "dir=out", and
359 * "inout" = "dir=in or dir=out", and the parser could conceivably
360 * special-case "in", "out", and "inout" as expressions for backwards
361 * compatibility, so all is not (yet) lost.
365 * Set up flags that might or might not be supported depending on the
366 * version of libpcap we're using.
368 #if defined(HAVE_PCAP_CREATE) || defined(_WIN32)
370 #define B_FLAG_USAGE " [ -B size ]"
371 #else /* defined(HAVE_PCAP_CREATE) || defined(_WIN32) */
374 #endif /* defined(HAVE_PCAP_CREATE) || defined(_WIN32) */
376 #ifdef HAVE_PCAP_CREATE
378 #else /* HAVE_PCAP_CREATE */
380 #endif /* HAVE_PCAP_CREATE */
382 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
384 #define j_FLAG_USAGE " [ -j tstamptype ]"
386 #else /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */
390 #endif /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */
392 #ifdef HAVE_PCAP_FINDALLDEVS
398 #ifdef HAVE_PCAP_DUMP_FLUSH
404 #ifdef HAVE_PCAP_SETDIRECTION
410 #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:#"
415 * We do not currently have long options corresponding to all short
416 * options; we should probably pick appropriate option names for them.
418 * However, the short options where the number of times the option is
419 * specified matters, such as -v and -d and -t, should probably not
420 * just map to a long option, as saying
422 * tcpdump --verbose --verbose
424 * doesn't make sense; it should be --verbosity={N} or something such
427 * For long options with no corresponding short options, we define values
428 * outside the range of ASCII graphic characters, make that the last
429 * component of the entry for the long option, and have a case for that
430 * option in the switch statement.
432 #define OPTION_VERSION 128
433 #define OPTION_TSTAMP_PRECISION 129
434 #define OPTION_IMMEDIATE_MODE 130
436 static const struct option longopts
[] = {
437 #if defined(HAVE_PCAP_CREATE) || defined(_WIN32)
438 { "buffer-size", required_argument
, NULL
, 'B' },
440 { "list-interfaces", no_argument
, NULL
, 'D' },
441 { "help", no_argument
, NULL
, 'h' },
442 { "interface", required_argument
, NULL
, 'i' },
443 #ifdef HAVE_PCAP_CREATE
444 { "monitor-mode", no_argument
, NULL
, 'I' },
446 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
447 { "time-stamp-type", required_argument
, NULL
, 'j' },
448 { "list-time-stamp-types", no_argument
, NULL
, 'J' },
450 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
451 { "time-stamp-precision", required_argument
, NULL
, OPTION_TSTAMP_PRECISION
},
453 { "dont-verify-checksums", no_argument
, NULL
, 'K' },
454 { "list-data-link-types", no_argument
, NULL
, 'L' },
455 { "no-optimize", no_argument
, NULL
, 'O' },
456 { "no-promiscuous-mode", no_argument
, NULL
, 'p' },
457 #ifdef HAVE_PCAP_SETDIRECTION
458 { "direction", required_argument
, NULL
, 'Q' },
460 { "snapshot-length", required_argument
, NULL
, 's' },
461 { "absolute-tcp-sequence-numbers", no_argument
, NULL
, 'S' },
462 #ifdef HAVE_PCAP_DUMP_FLUSH
463 { "packet-buffered", no_argument
, NULL
, 'U' },
465 { "linktype", required_argument
, NULL
, 'y' },
466 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
467 { "immediate-mode", no_argument
, NULL
, OPTION_IMMEDIATE_MODE
},
469 #if defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG)
470 { "debug-filter-parser", no_argument
, NULL
, 'Y' },
472 { "relinquish-privileges", required_argument
, NULL
, 'Z' },
473 { "number", no_argument
, NULL
, '#' },
474 { "version", no_argument
, NULL
, OPTION_VERSION
},
479 /* Drop root privileges and chroot if necessary */
481 droproot(const char *username
, const char *chroot_dir
)
483 struct passwd
*pw
= NULL
;
485 if (chroot_dir
&& !username
) {
486 fprintf(stderr
, "%s: Chroot without dropping root is insecure\n",
491 pw
= getpwnam(username
);
494 if (chroot(chroot_dir
) != 0 || chdir ("/") != 0) {
495 fprintf(stderr
, "%s: Couldn't chroot/chdir to '%.64s': %s\n",
496 program_name
, chroot_dir
, pcap_strerror(errno
));
500 #ifdef HAVE_LIBCAP_NG
502 int ret
= capng_change_id(pw
->pw_uid
, pw
->pw_gid
, CAPNG_NO_FLAG
);
504 fprintf(stderr
, "error : ret %d\n", ret
);
506 fprintf(stderr
, "dropped privs to %s\n", username
);
510 if (initgroups(pw
->pw_name
, pw
->pw_gid
) != 0 ||
511 setgid(pw
->pw_gid
) != 0 || setuid(pw
->pw_uid
) != 0) {
512 fprintf(stderr
, "%s: Couldn't change to '%.32s' uid=%lu gid=%lu: %s\n",
513 program_name
, username
,
514 (unsigned long)pw
->pw_uid
,
515 (unsigned long)pw
->pw_gid
,
516 pcap_strerror(errno
));
520 fprintf(stderr
, "dropped privs to %s\n", username
);
522 #endif /* HAVE_LIBCAP_NG */
525 fprintf(stderr
, "%s: Couldn't find user '%.32s'\n",
526 program_name
, username
);
529 #ifdef HAVE_LIBCAP_NG
530 /* We don't need CAP_SETUID and CAP_SETGID any more. */
533 CAPNG_EFFECTIVE
| CAPNG_PERMITTED
,
537 capng_apply(CAPNG_SELECT_BOTH
);
538 #endif /* HAVE_LIBCAP_NG */
559 MakeFilename(char *buffer
, char *orig_name
, int cnt
, int max_chars
)
561 char *filename
= malloc(PATH_MAX
+ 1);
562 if (filename
== NULL
)
563 error("Makefilename: malloc");
565 /* Process with strftime if Gflag is set. */
569 /* Convert Gflag_time to a usable format */
570 if ((local_tm
= localtime(&Gflag_time
)) == NULL
) {
571 error("MakeTimedFilename: localtime");
574 /* There's no good way to detect an error in strftime since a return
575 * value of 0 isn't necessarily failure.
577 strftime(filename
, PATH_MAX
, orig_name
, local_tm
);
579 strncpy(filename
, orig_name
, PATH_MAX
);
582 if (cnt
== 0 && max_chars
== 0)
583 strncpy(buffer
, filename
, PATH_MAX
+ 1);
585 if (snprintf(buffer
, PATH_MAX
+ 1, "%s%0*d", filename
, max_chars
, cnt
) > PATH_MAX
)
586 /* Report an error if the filename is too large */
587 error("too many output files or filename is too long (> %d)", PATH_MAX
);
592 get_next_file(FILE *VFile
, char *ptr
)
596 ret
= fgets(ptr
, PATH_MAX
, VFile
);
600 if (ptr
[strlen(ptr
) - 1] == '\n')
601 ptr
[strlen(ptr
) - 1] = '\0';
606 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
608 tstamp_precision_from_string(const char *precision
)
610 if (strncmp(precision
, "nano", strlen("nano")) == 0)
611 return PCAP_TSTAMP_PRECISION_NANO
;
613 if (strncmp(precision
, "micro", strlen("micro")) == 0)
614 return PCAP_TSTAMP_PRECISION_MICRO
;
620 tstamp_precision_to_string(int precision
)
624 case PCAP_TSTAMP_PRECISION_MICRO
:
627 case PCAP_TSTAMP_PRECISION_NANO
:
638 * Ensure that, on a dump file's descriptor, we have all the rights
639 * necessary to make the standard I/O library work with an fdopen()ed
640 * FILE * from that descriptor.
642 * A long time ago, in a galaxy far far away, AT&T decided that, instead
643 * of providing separate APIs for getting and setting the FD_ flags on a
644 * descriptor, getting and setting the O_ flags on a descriptor, and
645 * locking files, they'd throw them all into a kitchen-sink fcntl() call
646 * along the lines of ioctl(), the fact that ioctl() operations are
647 * largely specific to particular character devices but fcntl() operations
648 * are either generic to all descriptors or generic to all descriptors for
649 * regular files nonwithstanding.
651 * The Capsicum people decided that fine-grained control of descriptor
652 * operations was required, so that you need to grant permission for
653 * reading, writing, seeking, and fcntl-ing. The latter, courtesy of
654 * AT&T's decision, means that "fcntl-ing" isn't a thing, but a motley
655 * collection of things, so there are *individual* fcntls for which
656 * permission needs to be granted.
658 * The FreeBSD standard I/O people implemented some optimizations that
659 * requires that the standard I/O routines be able to determine whether
660 * the descriptor for the FILE * is open append-only or not; as that
661 * descriptor could have come from an open() rather than an fopen(),
662 * that requires that it be able to do an F_GETFL fcntl() to read
665 * Tcpdump uses ftell() to determine how much data has been written
666 * to a file in order to, when used with -C, determine when it's time
667 * to rotate capture files. ftell() therefore needs to do an lseek()
668 * to find out the file offset and must, thanks to the aforementioned
669 * optimization, also know whether the descriptor is open append-only
672 * The net result of all the above is that we need to grant CAP_SEEK,
673 * CAP_WRITE, and CAP_FCNTL with the CAP_FCNTL_GETFL subcapability.
675 * Perhaps this is the universe's way of saying that either
677 * 1) there needs to be an fopenat() call and a pcap_dump_openat() call
678 * using it, so that Capsicum-capable tcpdump wouldn't need to do
683 * 2) there needs to be a cap_fdopen() call in the FreeBSD standard
684 * I/O library that knows what rights are needed by the standard
685 * I/O library, based on the open mode, and assigns them, perhaps
686 * with an additional argument indicating, for example, whether
687 * seeking should be allowed, so that tcpdump doesn't need to know
688 * what the standard I/O library happens to require this week.
691 set_dumper_capsicum_rights(pcap_dumper_t
*p
)
693 int fd
= fileno(pcap_dump_file(p
));
696 cap_rights_init(&rights
, CAP_SEEK
, CAP_WRITE
, CAP_FCNTL
);
697 if (cap_rights_limit(fd
, &rights
) < 0 && errno
!= ENOSYS
) {
698 error("unable to limit dump descriptor");
700 if (cap_fcntls_limit(fd
, CAP_FCNTL_GETFL
) < 0 && errno
!= ENOSYS
) {
701 error("unable to limit dump descriptor fcntls");
707 main(int argc
, char **argv
)
709 register int cnt
, op
, i
;
710 bpf_u_int32 localnet
=0 , netmask
= 0;
711 int timezone_offset
= 0;
712 register char *cp
, *infile
, *cmdbuf
, *device
, *RFileName
, *VFileName
, *WFileName
;
713 pcap_handler callback
;
716 const char *dlt_name
;
717 struct bpf_program fcode
;
719 RETSIGTYPE (*oldhandler
)(int);
721 struct dump_info dumpinfo
;
722 u_char
*pcap_userdata
;
723 char ebuf
[PCAP_ERRBUF_SIZE
];
724 char VFileLine
[PATH_MAX
+ 1];
725 char *username
= NULL
;
726 char *chroot_dir
= NULL
;
729 #ifdef HAVE_PCAP_FINDALLDEVS
730 pcap_if_t
*devpointer
;
738 #endif /* HAVE_CAPSICUM */
739 int Bflag
= 0; /* buffer size */
740 int jflag
= -1; /* packet time stamp source */
741 int Oflag
= 1; /* run filter code optimizer */
742 int pflag
= 0; /* don't go promiscuous */
744 const char *yflag_dlt_name
= NULL
;
746 netdissect_options Ndo
;
747 netdissect_options
*ndo
= &Ndo
;
748 int immediate_mode
= 0;
750 memset(ndo
, 0, sizeof(*ndo
));
751 ndo_set_function_pointers(ndo
);
752 ndo
->ndo_snaplen
= DEFAULT_SNAPLEN
;
762 if ((cp
= strrchr(argv
[0], '/')) != NULL
)
763 ndo
->program_name
= program_name
= cp
+ 1;
765 ndo
->program_name
= program_name
= argv
[0];
768 if (pcap_wsockinit() != 0)
769 error("Attempting to initialize Winsock failed");
773 * On platforms where the CPU doesn't support unaligned loads,
774 * force unaligned accesses to abort with SIGBUS, rather than
775 * being fixed up (slowly) by the OS kernel; on those platforms,
776 * misaligned accesses are bugs, and we want tcpdump to crash so
777 * that the bugs are reported.
779 if (abort_on_misalignment(ebuf
, sizeof(ebuf
)) < 0)
787 (op
= getopt_long(argc
, argv
, SHORTOPTS
, longopts
, NULL
)) != -1)
791 /* compatibility for old -a */
802 #if defined(HAVE_PCAP_CREATE) || defined(_WIN32)
804 Bflag
= atoi(optarg
)*1024;
806 error("invalid packet buffer size %s", optarg
);
808 #endif /* defined(HAVE_PCAP_CREATE) || defined(_WIN32) */
813 error("invalid packet count %s", optarg
);
817 Cflag
= atoi(optarg
) * 1000000;
819 error("invalid file size %s", optarg
);
839 #ifndef HAVE_LIBCRYPTO
840 warning("crypto code not compiled in");
842 ndo
->ndo_espsecret
= optarg
;
854 Gflag
= atoi(optarg
);
856 error("invalid number of seconds %s", optarg
);
858 /* We will create one file initially. */
861 /* Grab the current time for rotation use. */
862 if ((Gflag_time
= time(NULL
)) == (time_t)-1) {
863 error("main: can't get current time: %s",
864 pcap_strerror(errno
));
878 if (optarg
[0] == '0' && optarg
[1] == 0)
879 error("Invalid adapter index");
881 #ifdef HAVE_PCAP_FINDALLDEVS
883 * If the argument is a number, treat it as
884 * an index into the list of adapters, as
885 * printed by "tcpdump -D".
887 * This should be OK on UNIX systems, as interfaces
888 * shouldn't have names that begin with digits.
889 * It can be useful on Windows, where more than
890 * one interface can have the same name.
892 devnum
= strtol(optarg
, &end
, 10);
893 if (optarg
!= end
&& *end
== '\0') {
895 error("Invalid adapter index");
897 if (pcap_findalldevs(&devpointer
, ebuf
) < 0)
901 * Look for the devnum-th entry
902 * in the list of devices
906 i
< devnum
-1 && devpointer
!= NULL
;
907 i
++, devpointer
= devpointer
->next
)
909 if (devpointer
== NULL
)
910 error("Invalid adapter index");
912 device
= devpointer
->name
;
915 #endif /* HAVE_PCAP_FINDALLDEVS */
919 #ifdef HAVE_PCAP_CREATE
923 #endif /* HAVE_PCAP_CREATE */
925 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
927 jflag
= pcap_tstamp_type_name_to_val(optarg
);
929 error("invalid time stamp type %s", optarg
);
940 * _IOLBF is the same as _IOFBF in Microsoft's C
941 * libraries; the only alternative they offer
944 * XXX - this should really be checking for MSVC++,
945 * not _WIN32, if, for example, MinGW has its own
946 * C library that is more UNIX-compatible.
948 setvbuf(stdout
, NULL
, _IONBF
, 0);
950 #ifdef HAVE_SETLINEBUF
953 setvbuf(stdout
, NULL
, _IOLBF
, 0);
964 if (smiLoadModule(optarg
) == 0) {
965 error("could not load MIB module %s", optarg
);
969 (void)fprintf(stderr
, "%s: ignoring option `-m %s' ",
970 program_name
, optarg
);
971 (void)fprintf(stderr
, "(no libsmi support)\n");
976 /* TCP-MD5 shared secret */
977 #ifndef HAVE_LIBCRYPTO
978 warning("crypto code not compiled in");
980 ndo
->ndo_sigsecret
= optarg
;
1001 ++ndo
->ndo_suppress_default_print
;
1004 #ifdef HAVE_PCAP_SETDIRECTION
1006 if (ascii_strcasecmp(optarg
, "in") == 0)
1008 else if (ascii_strcasecmp(optarg
, "out") == 0)
1010 else if (ascii_strcasecmp(optarg
, "inout") == 0)
1011 Qflag
= PCAP_D_INOUT
;
1013 error("unknown capture direction `%s'", optarg
);
1015 #endif /* HAVE_PCAP_SETDIRECTION */
1022 ndo
->ndo_snaplen
= strtol(optarg
, &end
, 0);
1023 if (optarg
== end
|| *end
!= '\0'
1024 || ndo
->ndo_snaplen
< 0 || ndo
->ndo_snaplen
> MAXIMUM_SNAPLEN
)
1025 error("invalid snaplen %s", optarg
);
1026 else if (ndo
->ndo_snaplen
== 0)
1027 ndo
->ndo_snaplen
= MAXIMUM_SNAPLEN
;
1039 if (ascii_strcasecmp(optarg
, "vat") == 0)
1040 ndo
->ndo_packettype
= PT_VAT
;
1041 else if (ascii_strcasecmp(optarg
, "wb") == 0)
1042 ndo
->ndo_packettype
= PT_WB
;
1043 else if (ascii_strcasecmp(optarg
, "rpc") == 0)
1044 ndo
->ndo_packettype
= PT_RPC
;
1045 else if (ascii_strcasecmp(optarg
, "rtp") == 0)
1046 ndo
->ndo_packettype
= PT_RTP
;
1047 else if (ascii_strcasecmp(optarg
, "rtcp") == 0)
1048 ndo
->ndo_packettype
= PT_RTCP
;
1049 else if (ascii_strcasecmp(optarg
, "snmp") == 0)
1050 ndo
->ndo_packettype
= PT_SNMP
;
1051 else if (ascii_strcasecmp(optarg
, "cnfp") == 0)
1052 ndo
->ndo_packettype
= PT_CNFP
;
1053 else if (ascii_strcasecmp(optarg
, "tftp") == 0)
1054 ndo
->ndo_packettype
= PT_TFTP
;
1055 else if (ascii_strcasecmp(optarg
, "aodv") == 0)
1056 ndo
->ndo_packettype
= PT_AODV
;
1057 else if (ascii_strcasecmp(optarg
, "carp") == 0)
1058 ndo
->ndo_packettype
= PT_CARP
;
1059 else if (ascii_strcasecmp(optarg
, "radius") == 0)
1060 ndo
->ndo_packettype
= PT_RADIUS
;
1061 else if (ascii_strcasecmp(optarg
, "zmtp1") == 0)
1062 ndo
->ndo_packettype
= PT_ZMTP1
;
1063 else if (ascii_strcasecmp(optarg
, "vxlan") == 0)
1064 ndo
->ndo_packettype
= PT_VXLAN
;
1065 else if (ascii_strcasecmp(optarg
, "pgm") == 0)
1066 ndo
->ndo_packettype
= PT_PGM
;
1067 else if (ascii_strcasecmp(optarg
, "pgm_zmtp1") == 0)
1068 ndo
->ndo_packettype
= PT_PGM_ZMTP1
;
1069 else if (ascii_strcasecmp(optarg
, "lmp") == 0)
1070 ndo
->ndo_packettype
= PT_LMP
;
1072 error("unknown packet type `%s'", optarg
);
1079 #ifdef HAVE_PCAP_DUMP_FLUSH
1098 Wflag
= atoi(optarg
);
1100 error("invalid number of output files %s", optarg
);
1101 WflagChars
= getWflagChars(Wflag
);
1106 ++ndo
->ndo_suppress_default_print
;
1111 ++ndo
->ndo_suppress_default_print
;
1115 yflag_dlt_name
= optarg
;
1117 pcap_datalink_name_to_val(yflag_dlt_name
);
1119 error("invalid data link type %s", yflag_dlt_name
);
1122 #if defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG)
1125 /* Undocumented flag */
1126 #ifdef HAVE_PCAP_DEBUG
1127 extern int pcap_debug
;
1137 zflag
= strdup(optarg
);
1139 error("Unable to allocate memory for -z argument");
1143 username
= strdup(optarg
);
1144 if (username
== NULL
)
1145 error("Unable to allocate memory for -Z argument");
1149 ndo
->ndo_packet_number
= 1;
1152 case OPTION_VERSION
:
1157 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
1158 case OPTION_TSTAMP_PRECISION
:
1159 ndo
->ndo_tstamp_precision
= tstamp_precision_from_string(optarg
);
1160 if (ndo
->ndo_tstamp_precision
< 0)
1161 error("unsupported time stamp precision");
1165 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
1166 case OPTION_IMMEDIATE_MODE
:
1177 #ifdef HAVE_PCAP_FINDALLDEVS
1179 show_devices_and_exit();
1182 switch (ndo
->ndo_tflag
) {
1184 case 0: /* Default */
1185 case 4: /* Default + Date*/
1186 timezone_offset
= gmt2local(0);
1189 case 1: /* No time stamp */
1190 case 2: /* Unix timeval style */
1191 case 3: /* Microseconds since previous packet */
1192 case 5: /* Microseconds since first packet */
1195 default: /* Not supported */
1196 error("only -t, -tt, -ttt, -tttt and -ttttt are supported");
1200 if (ndo
->ndo_fflag
!= 0 && (VFileName
!= NULL
|| RFileName
!= NULL
))
1201 error("-f can not be used with -V or -r");
1203 if (VFileName
!= NULL
&& RFileName
!= NULL
)
1204 error("-V and -r are mutually exclusive.");
1206 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
1208 * If we're printing dissected packets to the standard output
1209 * rather than saving raw packets to a file, and the standard
1210 * output is a terminal, use immediate mode, as the user's
1211 * probably expecting to see packets pop up immediately.
1213 if (WFileName
== NULL
&& isatty(1))
1218 /* if run as root, prepare for chrooting */
1219 if (getuid() == 0 || geteuid() == 0) {
1220 /* future extensibility for cmd-line arguments */
1222 chroot_dir
= WITH_CHROOT
;
1227 /* if run as root, prepare for dropping root privileges */
1228 if (getuid() == 0 || geteuid() == 0) {
1229 /* Run with '-Z root' to restore old behaviour */
1231 username
= WITH_USER
;
1235 if (RFileName
!= NULL
|| VFileName
!= NULL
) {
1237 * If RFileName is non-null, it's the pathname of a
1238 * savefile to read. If VFileName is non-null, it's
1239 * the pathname of a file containing a list of pathnames
1240 * (one per line) of savefiles to read.
1242 * In either case, we're reading a savefile, not doing
1247 * We don't need network access, so relinquish any set-UID
1248 * or set-GID privileges we have (if any).
1250 * We do *not* want set-UID privileges when opening a
1251 * trace file, as that might let the user read other
1252 * people's trace files (especially if we're set-UID
1255 if (setgid(getgid()) != 0 || setuid(getuid()) != 0 )
1256 fprintf(stderr
, "Warning: setgid/setuid failed !\n");
1258 if (VFileName
!= NULL
) {
1259 if (VFileName
[0] == '-' && VFileName
[1] == '\0')
1262 VFile
= fopen(VFileName
, "r");
1265 error("Unable to open file: %s\n", strerror(errno
));
1267 ret
= get_next_file(VFile
, VFileLine
);
1269 error("Nothing in %s\n", VFileName
);
1270 RFileName
= VFileLine
;
1273 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
1274 pd
= pcap_open_offline_with_tstamp_precision(RFileName
,
1275 ndo
->ndo_tstamp_precision
, ebuf
);
1277 pd
= pcap_open_offline(RFileName
, ebuf
);
1282 #ifdef HAVE_CAPSICUM
1283 cap_rights_init(&rights
, CAP_READ
);
1284 if (cap_rights_limit(fileno(pcap_file(pd
)), &rights
) < 0 &&
1286 error("unable to limit pcap descriptor");
1289 dlt
= pcap_datalink(pd
);
1290 dlt_name
= pcap_datalink_val_to_name(dlt
);
1291 if (dlt_name
== NULL
) {
1292 fprintf(stderr
, "reading from file %s, link-type %u\n",
1296 "reading from file %s, link-type %s (%s)\n",
1297 RFileName
, dlt_name
,
1298 pcap_datalink_val_to_description(dlt
));
1302 * We're doing a live capture.
1304 if (device
== NULL
) {
1305 device
= pcap_lookupdev(ebuf
);
1311 * Print a message to the standard error on Windows.
1312 * XXX - why do it here, with a different message?
1314 if(strlen(device
) == 1) /* we assume that an ASCII string is always longer than 1 char */
1315 { /* a Unicode string has a \0 as second byte (so strlen() is 1) */
1316 fprintf(stderr
, "%s: listening on %ws\n", program_name
, device
);
1320 fprintf(stderr
, "%s: listening on %s\n", program_name
, device
);
1325 #ifdef HAVE_PCAP_CREATE
1326 pd
= pcap_create(device
, ebuf
);
1329 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
1331 show_tstamp_types_and_exit(device
);
1333 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
1334 status
= pcap_set_tstamp_precision(pd
, ndo
->ndo_tstamp_precision
);
1336 error("%s: Can't set %ssecond time stamp precision: %s",
1338 tstamp_precision_to_string(ndo
->ndo_tstamp_precision
),
1339 pcap_statustostr(status
));
1342 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
1343 if (immediate_mode
) {
1344 status
= pcap_set_immediate_mode(pd
, 1);
1346 error("%s: Can't set immediate mode: %s",
1348 pcap_statustostr(status
));
1352 * Is this an interface that supports monitor mode?
1354 if (pcap_can_set_rfmon(pd
) == 1)
1355 supports_monitor_mode
= 1;
1357 supports_monitor_mode
= 0;
1358 status
= pcap_set_snaplen(pd
, ndo
->ndo_snaplen
);
1360 error("%s: Can't set snapshot length: %s",
1361 device
, pcap_statustostr(status
));
1362 status
= pcap_set_promisc(pd
, !pflag
);
1364 error("%s: Can't set promiscuous mode: %s",
1365 device
, pcap_statustostr(status
));
1367 status
= pcap_set_rfmon(pd
, 1);
1369 error("%s: Can't set monitor mode: %s",
1370 device
, pcap_statustostr(status
));
1372 status
= pcap_set_timeout(pd
, 1000);
1374 error("%s: pcap_set_timeout failed: %s",
1375 device
, pcap_statustostr(status
));
1377 status
= pcap_set_buffer_size(pd
, Bflag
);
1379 error("%s: Can't set buffer size: %s",
1380 device
, pcap_statustostr(status
));
1382 #ifdef HAVE_PCAP_SET_TSTAMP_TYPE
1384 status
= pcap_set_tstamp_type(pd
, jflag
);
1386 error("%s: Can't set time stamp type: %s",
1387 device
, pcap_statustostr(status
));
1390 status
= pcap_activate(pd
);
1393 * pcap_activate() failed.
1395 cp
= pcap_geterr(pd
);
1396 if (status
== PCAP_ERROR
)
1398 else if ((status
== PCAP_ERROR_NO_SUCH_DEVICE
||
1399 status
== PCAP_ERROR_PERM_DENIED
) &&
1401 error("%s: %s\n(%s)", device
,
1402 pcap_statustostr(status
), cp
);
1404 error("%s: %s", device
,
1405 pcap_statustostr(status
));
1406 } else if (status
> 0) {
1408 * pcap_activate() succeeded, but it's warning us
1409 * of a problem it had.
1411 cp
= pcap_geterr(pd
);
1412 if (status
== PCAP_WARNING
)
1414 else if (status
== PCAP_WARNING_PROMISC_NOTSUP
&&
1416 warning("%s: %s\n(%s)", device
,
1417 pcap_statustostr(status
), cp
);
1419 warning("%s: %s", device
,
1420 pcap_statustostr(status
));
1422 #ifdef HAVE_PCAP_SETDIRECTION
1424 status
= pcap_setdirection(pd
, Qflag
);
1426 error("%s: pcap_setdirection() failed: %s",
1427 device
, pcap_geterr(pd
));
1429 #endif /* HAVE_PCAP_SETDIRECTION */
1432 pd
= pcap_open_live(device
, snaplen
, !pflag
, 1000, ebuf
);
1436 warning("%s", ebuf
);
1437 #endif /* HAVE_PCAP_CREATE */
1439 * Let user own process after socket has been opened.
1442 if (setgid(getgid()) != 0 || setuid(getuid()) != 0)
1443 fprintf(stderr
, "Warning: setgid/setuid failed !\n");
1445 #if !defined(HAVE_PCAP_CREATE) && defined(_WIN32)
1447 if(pcap_setbuff(pd
, Bflag
)==-1){
1448 error("%s", pcap_geterr(pd
));
1450 #endif /* !defined(HAVE_PCAP_CREATE) && defined(_WIN32) */
1452 show_dlts_and_exit(device
);
1453 if (yflag_dlt
>= 0) {
1454 #ifdef HAVE_PCAP_SET_DATALINK
1455 if (pcap_set_datalink(pd
, yflag_dlt
) < 0)
1456 error("%s", pcap_geterr(pd
));
1459 * We don't actually support changing the
1460 * data link type, so we only let them
1461 * set it to what it already is.
1463 if (yflag_dlt
!= pcap_datalink(pd
)) {
1464 error("%s is not one of the DLTs supported by this device\n",
1468 (void)fprintf(stderr
, "%s: data link type %s\n",
1469 program_name
, yflag_dlt_name
);
1470 (void)fflush(stderr
);
1472 i
= pcap_snapshot(pd
);
1473 if (ndo
->ndo_snaplen
< i
) {
1474 warning("snaplen raised from %d to %d", ndo
->ndo_snaplen
, i
);
1475 ndo
->ndo_snaplen
= i
;
1477 if(ndo
->ndo_fflag
!= 0) {
1478 if (pcap_lookupnet(device
, &localnet
, &netmask
, ebuf
) < 0) {
1479 warning("foreign (-f) flag used but: %s", ebuf
);
1485 cmdbuf
= read_infile(infile
);
1487 cmdbuf
= copy_argv(&argv
[optind
]);
1489 if (pcap_compile(pd
, &fcode
, cmdbuf
, Oflag
, netmask
) < 0)
1490 error("%s", pcap_geterr(pd
));
1492 bpf_dump(&fcode
, dflag
);
1497 init_print(ndo
, localnet
, netmask
, timezone_offset
);
1500 (void)setsignal(SIGPIPE
, cleanup
);
1501 (void)setsignal(SIGTERM
, cleanup
);
1502 (void)setsignal(SIGINT
, cleanup
);
1504 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
1505 (void)setsignal(SIGCHLD
, child_cleanup
);
1507 /* Cooperate with nohup(1) */
1509 if ((oldhandler
= setsignal(SIGHUP
, cleanup
)) != SIG_DFL
)
1510 (void)setsignal(SIGHUP
, oldhandler
);
1515 * If a user name was specified with "-Z", attempt to switch to
1516 * that user's UID. This would probably be used with sudo,
1517 * to allow tcpdump to be run in a special restricted
1518 * account (if you just want to allow users to open capture
1519 * devices, and can't just give users that permission,
1520 * you'd make tcpdump set-UID or set-GID).
1522 * Tcpdump doesn't necessarily write only to one savefile;
1523 * the general only way to allow a -Z instance to write to
1524 * savefiles as the user under whose UID it's run, rather
1525 * than as the user specified with -Z, would thus be to switch
1526 * to the original user ID before opening a capture file and
1527 * then switch back to the -Z user ID after opening the savefile.
1528 * Switching to the -Z user ID only after opening the first
1529 * savefile doesn't handle the general case.
1532 if (getuid() == 0 || geteuid() == 0) {
1533 #ifdef HAVE_LIBCAP_NG
1534 /* Initialize capng */
1535 capng_clear(CAPNG_SELECT_BOTH
);
1539 CAPNG_PERMITTED
| CAPNG_EFFECTIVE
,
1548 CAPNG_PERMITTED
| CAPNG_EFFECTIVE
,
1552 capng_apply(CAPNG_SELECT_BOTH
);
1553 #endif /* HAVE_LIBCAP_NG */
1554 if (username
|| chroot_dir
)
1555 droproot(username
, chroot_dir
);
1560 if (pcap_setfilter(pd
, &fcode
) < 0)
1561 error("%s", pcap_geterr(pd
));
1562 #ifdef HAVE_CAPSICUM
1563 if (RFileName
== NULL
&& VFileName
== NULL
) {
1564 static const unsigned long cmds
[] = { BIOCGSTATS
};
1566 cap_rights_init(&rights
, CAP_IOCTL
, CAP_READ
);
1567 if (cap_rights_limit(pcap_fileno(pd
), &rights
) < 0 &&
1569 error("unable to limit pcap descriptor");
1571 if (cap_ioctls_limit(pcap_fileno(pd
), cmds
,
1572 sizeof(cmds
) / sizeof(cmds
[0])) < 0 && errno
!= ENOSYS
) {
1573 error("unable to limit ioctls on pcap descriptor");
1579 /* Do not exceed the default PATH_MAX for files. */
1580 dumpinfo
.CurrentFileName
= (char *)malloc(PATH_MAX
+ 1);
1582 if (dumpinfo
.CurrentFileName
== NULL
)
1583 error("malloc of dumpinfo.CurrentFileName");
1585 /* We do not need numbering for dumpfiles if Cflag isn't set. */
1587 MakeFilename(dumpinfo
.CurrentFileName
, WFileName
, 0, WflagChars
);
1589 MakeFilename(dumpinfo
.CurrentFileName
, WFileName
, 0, 0);
1591 p
= pcap_dump_open(pd
, dumpinfo
.CurrentFileName
);
1592 #ifdef HAVE_LIBCAP_NG
1593 /* Give up CAP_DAC_OVERRIDE capability.
1594 * Only allow it to be restored if the -C or -G flag have been
1595 * set since we may need to create more files later on.
1599 (Cflag
|| Gflag
? 0 : CAPNG_PERMITTED
)
1603 capng_apply(CAPNG_SELECT_BOTH
);
1604 #endif /* HAVE_LIBCAP_NG */
1606 error("%s", pcap_geterr(pd
));
1607 #ifdef HAVE_CAPSICUM
1608 set_dumper_capsicum_rights(p
);
1610 if (Cflag
!= 0 || Gflag
!= 0) {
1611 #ifdef HAVE_CAPSICUM
1612 dumpinfo
.WFileName
= strdup(basename(WFileName
));
1613 if (dumpinfo
.WFileName
== NULL
) {
1614 error("Unable to allocate memory for file %s",
1617 dumpinfo
.dirfd
= open(dirname(WFileName
),
1618 O_DIRECTORY
| O_RDONLY
);
1619 if (dumpinfo
.dirfd
< 0) {
1620 error("unable to open directory %s",
1621 dirname(WFileName
));
1623 cap_rights_init(&rights
, CAP_CREATE
, CAP_FCNTL
,
1624 CAP_FTRUNCATE
, CAP_LOOKUP
, CAP_SEEK
, CAP_WRITE
);
1625 if (cap_rights_limit(dumpinfo
.dirfd
, &rights
) < 0 &&
1627 error("unable to limit directory rights");
1629 if (cap_fcntls_limit(dumpinfo
.dirfd
, CAP_FCNTL_GETFL
) < 0 &&
1631 error("unable to limit dump descriptor fcntls");
1633 #else /* !HAVE_CAPSICUM */
1634 dumpinfo
.WFileName
= WFileName
;
1636 callback
= dump_packet_and_trunc
;
1639 pcap_userdata
= (u_char
*)&dumpinfo
;
1641 callback
= dump_packet
;
1642 pcap_userdata
= (u_char
*)p
;
1644 #ifdef HAVE_PCAP_DUMP_FLUSH
1649 dlt
= pcap_datalink(pd
);
1650 ndo
->ndo_if_printer
= get_if_printer(ndo
, dlt
);
1651 callback
= print_packet
;
1652 pcap_userdata
= (u_char
*)ndo
;
1655 #ifdef SIGNAL_REQ_INFO
1657 * We can't get statistics when reading from a file rather
1658 * than capturing from a device.
1660 if (RFileName
== NULL
)
1661 (void)setsignal(SIGNAL_REQ_INFO
, requestinfo
);
1664 if (ndo
->ndo_vflag
> 0 && WFileName
) {
1666 * When capturing to a file, "-v" means tcpdump should,
1667 * every 10 seconds, "v"erbosely report the number of
1670 #ifdef USE_WIN32_MM_TIMER
1671 /* call verbose_stats_dump() each 1000 +/-100msec */
1672 timer_id
= timeSetEvent(1000, 100, verbose_stats_dump
, 0, TIME_PERIODIC
);
1673 setvbuf(stderr
, NULL
, _IONBF
, 0);
1674 #elif defined(HAVE_ALARM)
1675 (void)setsignal(SIGALRM
, verbose_stats_dump
);
1681 if (RFileName
== NULL
) {
1683 * Live capture (if -V was specified, we set RFileName
1684 * to a file from the -V file). Print a message to
1685 * the standard error on UN*X.
1687 if (!ndo
->ndo_vflag
&& !WFileName
) {
1688 (void)fprintf(stderr
,
1689 "%s: verbose output suppressed, use -v or -vv for full protocol decode\n",
1692 (void)fprintf(stderr
, "%s: ", program_name
);
1693 dlt
= pcap_datalink(pd
);
1694 dlt_name
= pcap_datalink_val_to_name(dlt
);
1695 if (dlt_name
== NULL
) {
1696 (void)fprintf(stderr
, "listening on %s, link-type %u, capture size %u bytes\n",
1697 device
, dlt
, ndo
->ndo_snaplen
);
1699 (void)fprintf(stderr
, "listening on %s, link-type %s (%s), capture size %u bytes\n",
1701 pcap_datalink_val_to_description(dlt
), ndo
->ndo_snaplen
);
1703 (void)fflush(stderr
);
1707 #ifdef HAVE_CAPSICUM
1708 cansandbox
= (ndo
->ndo_nflag
&& VFileName
== NULL
&& zflag
== NULL
);
1709 if (cansandbox
&& cap_enter() < 0 && errno
!= ENOSYS
)
1710 error("unable to enter the capability mode");
1711 #endif /* HAVE_CAPSICUM */
1714 status
= pcap_loop(pd
, cnt
, callback
, pcap_userdata
);
1715 if (WFileName
== NULL
) {
1717 * We're printing packets. Flush the printed output,
1718 * so it doesn't get intermingled with error output.
1722 * We got interrupted, so perhaps we didn't
1723 * manage to finish a line we were printing.
1724 * Print an extra newline, just in case.
1728 (void)fflush(stdout
);
1732 * We got interrupted. If we are reading multiple
1733 * files (via -V) set these so that we stop.
1742 (void)fprintf(stderr
, "%s: pcap_loop: %s\n",
1743 program_name
, pcap_geterr(pd
));
1745 if (RFileName
== NULL
) {
1747 * We're doing a live capture. Report the capture
1753 if (VFileName
!= NULL
) {
1754 ret
= get_next_file(VFile
, VFileLine
);
1756 RFileName
= VFileLine
;
1757 pd
= pcap_open_offline(RFileName
, ebuf
);
1760 #ifdef HAVE_CAPSICUM
1761 cap_rights_init(&rights
, CAP_READ
);
1762 if (cap_rights_limit(fileno(pcap_file(pd
)),
1763 &rights
) < 0 && errno
!= ENOSYS
) {
1764 error("unable to limit pcap descriptor");
1767 new_dlt
= pcap_datalink(pd
);
1768 if (WFileName
&& new_dlt
!= dlt
)
1769 error("%s: new dlt does not match original", RFileName
);
1770 ndo
->ndo_if_printer
= get_if_printer(ndo
, new_dlt
);
1771 dlt_name
= pcap_datalink_val_to_name(new_dlt
);
1772 if (dlt_name
== NULL
) {
1773 fprintf(stderr
, "reading from file %s, link-type %u\n",
1774 RFileName
, new_dlt
);
1777 "reading from file %s, link-type %s (%s)\n",
1778 RFileName
, dlt_name
,
1779 pcap_datalink_val_to_description(new_dlt
));
1781 if (pcap_compile(pd
, &fcode
, cmdbuf
, Oflag
, netmask
) < 0)
1782 error("%s", pcap_geterr(pd
));
1783 if (pcap_setfilter(pd
, &fcode
) < 0)
1784 error("%s", pcap_geterr(pd
));
1788 while (ret
!= NULL
);
1791 exit(status
== -1 ? 1 : 0);
1794 /* make a clean exit on interrupts */
1796 cleanup(int signo _U_
)
1798 #ifdef USE_WIN32_MM_TIMER
1800 timeKillEvent(timer_id
);
1802 #elif defined(HAVE_ALARM)
1806 #ifdef HAVE_PCAP_BREAKLOOP
1808 * We have "pcap_breakloop()"; use it, so that we do as little
1809 * as possible in the signal handler (it's probably not safe
1810 * to do anything with standard I/O streams in a signal handler -
1811 * the ANSI C standard doesn't say it is).
1816 * We don't have "pcap_breakloop()"; this isn't safe, but
1817 * it's the best we can do. Print the summary if we're
1818 * not reading from a savefile - i.e., if we're doing a
1819 * live capture - and exit.
1821 if (pd
!= NULL
&& pcap_file(pd
) == NULL
) {
1823 * We got interrupted, so perhaps we didn't
1824 * manage to finish a line we were printing.
1825 * Print an extra newline, just in case.
1828 (void)fflush(stdout
);
1836 On windows, we do not use a fork, so we do not care less about
1837 waiting a child processes to die
1839 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
1841 child_cleanup(int signo _U_
)
1845 #endif /* HAVE_FORK && HAVE_VFORK */
1848 info(register int verbose
)
1850 struct pcap_stat stat
;
1853 * Older versions of libpcap didn't set ps_ifdrop on some
1854 * platforms; initialize it to 0 to handle that.
1857 if (pcap_stats(pd
, &stat
) < 0) {
1858 (void)fprintf(stderr
, "pcap_stats: %s\n", pcap_geterr(pd
));
1864 fprintf(stderr
, "%s: ", program_name
);
1866 (void)fprintf(stderr
, "%u packet%s captured", packets_captured
,
1867 PLURAL_SUFFIX(packets_captured
));
1869 fputs(", ", stderr
);
1872 (void)fprintf(stderr
, "%u packet%s received by filter", stat
.ps_recv
,
1873 PLURAL_SUFFIX(stat
.ps_recv
));
1875 fputs(", ", stderr
);
1878 (void)fprintf(stderr
, "%u packet%s dropped by kernel", stat
.ps_drop
,
1879 PLURAL_SUFFIX(stat
.ps_drop
));
1880 if (stat
.ps_ifdrop
!= 0) {
1882 fputs(", ", stderr
);
1885 (void)fprintf(stderr
, "%u packet%s dropped by interface\n",
1886 stat
.ps_ifdrop
, PLURAL_SUFFIX(stat
.ps_ifdrop
));
1892 #if defined(HAVE_FORK) || defined(HAVE_VFORK)
1894 compress_savefile(const char *filename
)
1903 * Set to lowest priority so that this doesn't disturb the capture
1906 setpriority(PRIO_PROCESS
, 0, NZERO
- 1);
1908 setpriority(PRIO_PROCESS
, 0, 19);
1910 if (execlp(zflag
, zflag
, filename
, (char *)NULL
) == -1)
1912 "compress_savefile:execlp(%s, %s): %s\n",
1922 #else /* HAVE_FORK && HAVE_VFORK */
1924 compress_savefile(const char *filename
)
1927 "compress_savefile failed. Functionality not implemented under your system\n");
1929 #endif /* HAVE_FORK && HAVE_VFORK */
1932 dump_packet_and_trunc(u_char
*user
, const struct pcap_pkthdr
*h
, const u_char
*sp
)
1934 struct dump_info
*dump_info
;
1940 dump_info
= (struct dump_info
*)user
;
1943 * XXX - this won't force the file to rotate on the specified time
1944 * boundary, but it will rotate on the first packet received after the
1945 * specified Gflag number of seconds. Note: if a Gflag time boundary
1946 * and a Cflag size boundary coincide, the time rotation will occur
1947 * first thereby cancelling the Cflag boundary (since the file should
1951 /* Check if it is time to rotate */
1954 /* Get the current time */
1955 if ((t
= time(NULL
)) == (time_t)-1) {
1956 error("dump_and_trunc_packet: can't get current_time: %s",
1957 pcap_strerror(errno
));
1961 /* If the time is greater than the specified window, rotate */
1962 if (t
- Gflag_time
>= Gflag
) {
1963 #ifdef HAVE_CAPSICUM
1968 /* Update the Gflag_time */
1970 /* Update Gflag_count */
1973 * Close the current file and open a new one.
1975 pcap_dump_close(dump_info
->p
);
1978 * Compress the file we just closed, if the user asked for it
1981 compress_savefile(dump_info
->CurrentFileName
);
1984 * Check to see if we've exceeded the Wflag (when
1987 if (Cflag
== 0 && Wflag
> 0 && Gflag_count
>= Wflag
) {
1988 (void)fprintf(stderr
, "Maximum file limit reached: %d\n",
1993 if (dump_info
->CurrentFileName
!= NULL
)
1994 free(dump_info
->CurrentFileName
);
1995 /* Allocate space for max filename + \0. */
1996 dump_info
->CurrentFileName
= (char *)malloc(PATH_MAX
+ 1);
1997 if (dump_info
->CurrentFileName
== NULL
)
1998 error("dump_packet_and_trunc: malloc");
2000 * Gflag was set otherwise we wouldn't be here. Reset the count
2001 * so multiple files would end with 1,2,3 in the filename.
2002 * The counting is handled with the -C flow after this.
2007 * This is always the first file in the Cflag
2009 * We also don't need numbering if Cflag is not set.
2012 MakeFilename(dump_info
->CurrentFileName
, dump_info
->WFileName
, 0,
2015 MakeFilename(dump_info
->CurrentFileName
, dump_info
->WFileName
, 0, 0);
2017 #ifdef HAVE_LIBCAP_NG
2018 capng_update(CAPNG_ADD
, CAPNG_EFFECTIVE
, CAP_DAC_OVERRIDE
);
2019 capng_apply(CAPNG_SELECT_BOTH
);
2020 #endif /* HAVE_LIBCAP_NG */
2021 #ifdef HAVE_CAPSICUM
2022 fd
= openat(dump_info
->dirfd
,
2023 dump_info
->CurrentFileName
,
2024 O_CREAT
| O_WRONLY
| O_TRUNC
, 0644);
2026 error("unable to open file %s",
2027 dump_info
->CurrentFileName
);
2029 fp
= fdopen(fd
, "w");
2031 error("unable to fdopen file %s",
2032 dump_info
->CurrentFileName
);
2034 dump_info
->p
= pcap_dump_fopen(dump_info
->pd
, fp
);
2035 #else /* !HAVE_CAPSICUM */
2036 dump_info
->p
= pcap_dump_open(dump_info
->pd
, dump_info
->CurrentFileName
);
2038 #ifdef HAVE_LIBCAP_NG
2039 capng_update(CAPNG_DROP
, CAPNG_EFFECTIVE
, CAP_DAC_OVERRIDE
);
2040 capng_apply(CAPNG_SELECT_BOTH
);
2041 #endif /* HAVE_LIBCAP_NG */
2042 if (dump_info
->p
== NULL
)
2043 error("%s", pcap_geterr(pd
));
2044 #ifdef HAVE_CAPSICUM
2045 set_dumper_capsicum_rights(dump_info
->p
);
2051 * XXX - this won't prevent capture files from getting
2052 * larger than Cflag - the last packet written to the
2053 * file could put it over Cflag.
2056 long size
= pcap_dump_ftell(dump_info
->p
);
2059 error("ftell fails on output file");
2061 #ifdef HAVE_CAPSICUM
2067 * Close the current file and open a new one.
2069 pcap_dump_close(dump_info
->p
);
2072 * Compress the file we just closed, if the user
2076 compress_savefile(dump_info
->CurrentFileName
);
2080 if (Cflag_count
>= Wflag
)
2083 if (dump_info
->CurrentFileName
!= NULL
)
2084 free(dump_info
->CurrentFileName
);
2085 dump_info
->CurrentFileName
= (char *)malloc(PATH_MAX
+ 1);
2086 if (dump_info
->CurrentFileName
== NULL
)
2087 error("dump_packet_and_trunc: malloc");
2088 MakeFilename(dump_info
->CurrentFileName
, dump_info
->WFileName
, Cflag_count
, WflagChars
);
2089 #ifdef HAVE_LIBCAP_NG
2090 capng_update(CAPNG_ADD
, CAPNG_EFFECTIVE
, CAP_DAC_OVERRIDE
);
2091 capng_apply(CAPNG_SELECT_BOTH
);
2092 #endif /* HAVE_LIBCAP_NG */
2093 #ifdef HAVE_CAPSICUM
2094 fd
= openat(dump_info
->dirfd
, dump_info
->CurrentFileName
,
2095 O_CREAT
| O_WRONLY
| O_TRUNC
, 0644);
2097 error("unable to open file %s",
2098 dump_info
->CurrentFileName
);
2100 fp
= fdopen(fd
, "w");
2102 error("unable to fdopen file %s",
2103 dump_info
->CurrentFileName
);
2105 dump_info
->p
= pcap_dump_fopen(dump_info
->pd
, fp
);
2106 #else /* !HAVE_CAPSICUM */
2107 dump_info
->p
= pcap_dump_open(dump_info
->pd
, dump_info
->CurrentFileName
);
2109 #ifdef HAVE_LIBCAP_NG
2110 capng_update(CAPNG_DROP
, CAPNG_EFFECTIVE
, CAP_DAC_OVERRIDE
);
2111 capng_apply(CAPNG_SELECT_BOTH
);
2112 #endif /* HAVE_LIBCAP_NG */
2113 if (dump_info
->p
== NULL
)
2114 error("%s", pcap_geterr(pd
));
2115 #ifdef HAVE_CAPSICUM
2116 set_dumper_capsicum_rights(dump_info
->p
);
2121 pcap_dump((u_char
*)dump_info
->p
, h
, sp
);
2122 #ifdef HAVE_PCAP_DUMP_FLUSH
2124 pcap_dump_flush(dump_info
->p
);
2133 dump_packet(u_char
*user
, const struct pcap_pkthdr
*h
, const u_char
*sp
)
2139 pcap_dump(user
, h
, sp
);
2140 #ifdef HAVE_PCAP_DUMP_FLUSH
2142 pcap_dump_flush((pcap_dumper_t
*)user
);
2151 print_packet(u_char
*user
, const struct pcap_pkthdr
*h
, const u_char
*sp
)
2157 pretty_print_packet((netdissect_options
*)user
, h
, sp
, packets_captured
);
2166 * XXX - there should really be libpcap calls to get the version
2167 * number as a string (the string would be generated from #defines
2168 * at run time, so that it's not generated from string constants
2169 * in the library, as, on many UNIX systems, those constants would
2170 * be statically linked into the application executable image, and
2171 * would thus reflect the version of libpcap on the system on
2172 * which the application was *linked*, not the system on which it's
2175 * That routine should be documented, unlike the "version[]"
2176 * string, so that UNIX vendors providing their own libpcaps
2177 * don't omit it (as a couple of vendors have...).
2179 * Packet.dll should perhaps also export a routine to return the
2180 * version number of the Packet.dll code, to supply the
2181 * "Wpcap_version" information on Windows.
2183 char WDversion
[]="current-git.tcpdump.org";
2184 #if !defined(HAVE_GENERATED_VERSION)
2185 char version
[]="current-git.tcpdump.org";
2187 char pcap_version
[]="current-git.tcpdump.org";
2188 char Wpcap_version
[]="3.1";
2191 #ifdef SIGNAL_REQ_INFO
2192 RETSIGTYPE
requestinfo(int signo _U_
)
2202 * Called once each second in verbose mode while dumping to file
2204 #ifdef USE_WIN32_MM_TIMER
2205 void CALLBACK
verbose_stats_dump (UINT timer_id _U_
, UINT msg _U_
, DWORD_PTR arg _U_
,
2206 DWORD_PTR dw1 _U_
, DWORD_PTR dw2 _U_
)
2208 struct pcap_stat stat
;
2210 if (infodelay
== 0 && pcap_stats(pd
, &stat
) >= 0)
2211 fprintf(stderr
, "Got %u\r", packets_captured
);
2213 #elif defined(HAVE_ALARM)
2214 static void verbose_stats_dump(int sig _U_
)
2216 struct pcap_stat stat
;
2218 if (infodelay
== 0 && pcap_stats(pd
, &stat
) >= 0)
2219 fprintf(stderr
, "Got %u\r", packets_captured
);
2224 USES_APPLE_DEPRECATED_API
2228 extern char version
[];
2229 #ifndef HAVE_PCAP_LIB_VERSION
2230 #if defined(_WIN32) || defined(HAVE_PCAP_VERSION)
2231 extern char pcap_version
[];
2232 #else /* defined(_WIN32) || defined(HAVE_PCAP_VERSION) */
2233 static char pcap_version
[] = "unknown";
2234 #endif /* defined(_WIN32) || defined(HAVE_PCAP_VERSION) */
2235 #endif /* HAVE_PCAP_LIB_VERSION */
2237 #ifdef HAVE_PCAP_LIB_VERSION
2239 (void)fprintf(stderr
, "%s version %s, based on tcpdump version %s\n", program_name
, WDversion
, version
);
2241 (void)fprintf(stderr
, "%s version %s\n", program_name
, version
);
2243 (void)fprintf(stderr
, "%s\n",pcap_lib_version());
2244 #else /* HAVE_PCAP_LIB_VERSION */
2246 (void)fprintf(stderr
, "%s version %s, based on tcpdump version %s\n", program_name
, WDversion
, version
);
2247 (void)fprintf(stderr
, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version
, pcap_version
);
2249 (void)fprintf(stderr
, "%s version %s\n", program_name
, version
);
2250 (void)fprintf(stderr
, "libpcap version %s\n", pcap_version
);
2252 #endif /* HAVE_PCAP_LIB_VERSION */
2254 #if defined(HAVE_LIBCRYPTO) && defined(SSLEAY_VERSION)
2255 (void)fprintf (stderr
, "%s\n", SSLeay_version(SSLEAY_VERSION
));
2259 (void)fprintf (stderr
, "SMI-library: %s\n", smi_version_string
);
2268 (void)fprintf(stderr
,
2269 "Usage: %s [-aAbd" D_FLAG
"efhH" I_FLAG J_FLAG
"KlLnNOpqStu" U_FLAG
"vxX#]" B_FLAG_USAGE
" [ -c count ]\n", program_name
);
2270 (void)fprintf(stderr
,
2271 "\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n");
2272 (void)fprintf(stderr
,
2273 "\t\t[ -i interface ]" j_FLAG_USAGE
" [ -M secret ] [ --number ]\n");
2274 #ifdef HAVE_PCAP_SETDIRECTION
2275 (void)fprintf(stderr
,
2276 "\t\t[ -Q in|out|inout ]\n");
2278 (void)fprintf(stderr
,
2279 "\t\t[ -r file ] [ -s snaplen ] ");
2280 #ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
2281 (void)fprintf(stderr
, "[ --time-stamp-precision precision ]\n");
2282 (void)fprintf(stderr
,
2285 #ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
2286 (void)fprintf(stderr
, "[ --immediate-mode ] ");
2288 (void)fprintf(stderr
, "[ -T type ] [ --version ] [ -V file ]\n");
2289 (void)fprintf(stderr
,
2290 "\t\t[ -w file ] [ -W filecount ] [ -y datalinktype ] [ -z command ]\n");
2291 (void)fprintf(stderr
,
2292 "\t\t[ -Z user ] [ expression ]\n");
2296 * c-style: whitesmith