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[dragonfly.git] / contrib / tcpdump-3.9 / tcpdump.c
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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.
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.
21 * Support for splitting captures into multiple files with a maximum
22 * file size:
24 * Copyright (c) 2001
25 * Seth Webster <swebster@sst.ll.mit.edu>
28 #ifndef lint
29 static const char copyright[] _U_ =
30 "@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
31 The Regents of the University of California. All rights reserved.\n";
32 static const char rcsid[] _U_ =
33 "@(#) $Header: /tcpdump/master/tcpdump/tcpdump.c,v 1.253.2.13 2007/09/12 19:48:51 guy Exp $ (LBL)";
34 #endif
37 * tcpdump - monitor tcp/ip traffic on an ethernet.
39 * First written in 1987 by Van Jacobson, Lawrence Berkeley Laboratory.
40 * Mercilessly hacked and occasionally improved since then via the
41 * combined efforts of Van, Steve McCanne and Craig Leres of LBL.
44 #ifdef HAVE_CONFIG_H
45 #include "config.h"
46 #endif
48 #include <tcpdump-stdinc.h>
50 #ifdef WIN32
51 #include "getopt.h"
52 #include "w32_fzs.h"
53 extern int strcasecmp (const char *__s1, const char *__s2);
54 extern int SIZE_BUF;
55 #define off_t long
56 #define uint UINT
57 #endif /* WIN32 */
59 #ifdef HAVE_SMI_H
60 #include <smi.h>
61 #endif
63 #include <pcap.h>
64 #include <signal.h>
65 #include <stdio.h>
66 #include <stdlib.h>
67 #include <string.h>
68 #ifndef WIN32
69 #include <pwd.h>
70 #include <grp.h>
71 #include <errno.h>
72 #endif /* WIN32 */
74 #include "netdissect.h"
75 #include "interface.h"
76 #include "addrtoname.h"
77 #include "machdep.h"
78 #include "setsignal.h"
79 #include "gmt2local.h"
80 #include "pcap-missing.h"
82 netdissect_options Gndo;
83 netdissect_options *gndo = &Gndo;
86 * Define the maximum number of files for the -C flag, and how many
87 * characters can be added to a filename for the -C flag (which
88 * should be enough to handle MAX_CFLAG - 1).
90 #define MAX_CFLAG 1000000
91 #define MAX_CFLAG_CHARS 6
93 int dflag; /* print filter code */
94 int Lflag; /* list available data link types and exit */
96 static int infodelay;
97 static int infoprint;
99 char *program_name;
101 int32_t thiszone; /* seconds offset from gmt to local time */
103 /* Forwards */
104 static RETSIGTYPE cleanup(int);
105 static void usage(void) __attribute__((noreturn));
106 static void show_dlts_and_exit(pcap_t *pd) __attribute__((noreturn));
108 static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
109 static void ndo_default_print(netdissect_options *, const u_char *, u_int);
110 static void dump_packet_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *);
111 static void dump_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
112 static void droproot(const char *, const char *);
113 static void ndo_error(netdissect_options *ndo, const char *fmt, ...);
114 static void ndo_warning(netdissect_options *ndo, const char *fmt, ...);
116 #ifdef SIGINFO
117 RETSIGTYPE requestinfo(int);
118 #endif
120 #if defined(USE_WIN32_MM_TIMER)
121 #include <MMsystem.h>
122 static UINT timer_id;
123 static void CALLBACK verbose_stats_dump(UINT, UINT, DWORD_PTR, DWORD_PTR, DWORD_PTR);
124 #elif defined(HAVE_ALARM)
125 static void verbose_stats_dump(int sig);
126 #endif
128 static void info(int);
129 static u_int packets_captured;
131 typedef u_int (*if_printer)(const struct pcap_pkthdr *, const u_char *);
133 struct printer {
134 if_printer f;
135 int type;
138 static struct printer printers[] = {
139 { arcnet_if_print, DLT_ARCNET },
140 #ifdef DLT_ARCNET_LINUX
141 { arcnet_linux_if_print, DLT_ARCNET_LINUX },
142 #endif
143 { ether_if_print, DLT_EN10MB },
144 { token_if_print, DLT_IEEE802 },
145 #ifdef DLT_LANE8023
146 { lane_if_print, DLT_LANE8023 },
147 #endif
148 #ifdef DLT_CIP
149 { cip_if_print, DLT_CIP },
150 #endif
151 #ifdef DLT_ATM_CLIP
152 { cip_if_print, DLT_ATM_CLIP },
153 #endif
154 { sl_if_print, DLT_SLIP },
155 #ifdef DLT_SLIP_BSDOS
156 { sl_bsdos_if_print, DLT_SLIP_BSDOS },
157 #endif
158 { ppp_if_print, DLT_PPP },
159 #ifdef DLT_PPP_WITHDIRECTION
160 { ppp_if_print, DLT_PPP_WITHDIRECTION },
161 #endif
162 #ifdef DLT_PPP_BSDOS
163 { ppp_bsdos_if_print, DLT_PPP_BSDOS },
164 #endif
165 { fddi_if_print, DLT_FDDI },
166 { null_if_print, DLT_NULL },
167 #ifdef DLT_LOOP
168 { null_if_print, DLT_LOOP },
169 #endif
170 { raw_if_print, DLT_RAW },
171 { atm_if_print, DLT_ATM_RFC1483 },
172 #ifdef DLT_C_HDLC
173 { chdlc_if_print, DLT_C_HDLC },
174 #endif
175 #ifdef DLT_HDLC
176 { chdlc_if_print, DLT_HDLC },
177 #endif
178 #ifdef DLT_PPP_SERIAL
179 { ppp_hdlc_if_print, DLT_PPP_SERIAL },
180 #endif
181 #ifdef DLT_PPP_ETHER
182 { pppoe_if_print, DLT_PPP_ETHER },
183 #endif
184 #ifdef DLT_LINUX_SLL
185 { sll_if_print, DLT_LINUX_SLL },
186 #endif
187 #ifdef DLT_IEEE802_11
188 { ieee802_11_if_print, DLT_IEEE802_11},
189 #endif
190 #ifdef DLT_LTALK
191 { ltalk_if_print, DLT_LTALK },
192 #endif
193 #if defined(DLT_PFLOG) && defined(HAVE_NET_PFVAR_H)
194 { pflog_if_print, DLT_PFLOG },
195 #endif
196 #ifdef DLT_FR
197 { fr_if_print, DLT_FR },
198 #endif
199 #ifdef DLT_FRELAY
200 { fr_if_print, DLT_FRELAY },
201 #endif
202 #ifdef DLT_SUNATM
203 { sunatm_if_print, DLT_SUNATM },
204 #endif
205 #ifdef DLT_IP_OVER_FC
206 { ipfc_if_print, DLT_IP_OVER_FC },
207 #endif
208 #ifdef DLT_PRISM_HEADER
209 { prism_if_print, DLT_PRISM_HEADER },
210 #endif
211 #ifdef DLT_IEEE802_11_RADIO
212 { ieee802_11_radio_if_print, DLT_IEEE802_11_RADIO },
213 #endif
214 #ifdef DLT_ENC
215 { enc_if_print, DLT_ENC },
216 #endif
217 #ifdef DLT_SYMANTEC_FIREWALL
218 { symantec_if_print, DLT_SYMANTEC_FIREWALL },
219 #endif
220 #ifdef DLT_APPLE_IP_OVER_IEEE1394
221 { ap1394_if_print, DLT_APPLE_IP_OVER_IEEE1394 },
222 #endif
223 #ifdef DLT_JUNIPER_ATM1
224 { juniper_atm1_print, DLT_JUNIPER_ATM1 },
225 #endif
226 #ifdef DLT_JUNIPER_ATM2
227 { juniper_atm2_print, DLT_JUNIPER_ATM2 },
228 #endif
229 #ifdef DLT_JUNIPER_MFR
230 { juniper_mfr_print, DLT_JUNIPER_MFR },
231 #endif
232 #ifdef DLT_JUNIPER_MLFR
233 { juniper_mlfr_print, DLT_JUNIPER_MLFR },
234 #endif
235 #ifdef DLT_JUNIPER_MLPPP
236 { juniper_mlppp_print, DLT_JUNIPER_MLPPP },
237 #endif
238 #ifdef DLT_JUNIPER_PPPOE
239 { juniper_pppoe_print, DLT_JUNIPER_PPPOE },
240 #endif
241 #ifdef DLT_JUNIPER_PPPOE_ATM
242 { juniper_pppoe_atm_print, DLT_JUNIPER_PPPOE_ATM },
243 #endif
244 #ifdef DLT_JUNIPER_GGSN
245 { juniper_ggsn_print, DLT_JUNIPER_GGSN },
246 #endif
247 #ifdef DLT_JUNIPER_ES
248 { juniper_es_print, DLT_JUNIPER_ES },
249 #endif
250 #ifdef DLT_JUNIPER_MONITOR
251 { juniper_monitor_print, DLT_JUNIPER_MONITOR },
252 #endif
253 #ifdef DLT_JUNIPER_SERVICES
254 { juniper_services_print, DLT_JUNIPER_SERVICES },
255 #endif
256 #ifdef DLT_JUNIPER_ETHER
257 { juniper_ether_print, DLT_JUNIPER_ETHER },
258 #endif
259 #ifdef DLT_JUNIPER_PPP
260 { juniper_ppp_print, DLT_JUNIPER_PPP },
261 #endif
262 #ifdef DLT_JUNIPER_FRELAY
263 { juniper_frelay_print, DLT_JUNIPER_FRELAY },
264 #endif
265 #ifdef DLT_JUNIPER_CHDLC
266 { juniper_chdlc_print, DLT_JUNIPER_CHDLC },
267 #endif
268 #ifdef DLT_MFR
269 { mfr_if_print, DLT_MFR },
270 #endif
271 { NULL, 0 },
274 static if_printer
275 lookup_printer(int type)
277 struct printer *p;
279 for (p = printers; p->f; ++p)
280 if (type == p->type)
281 return p->f;
283 return NULL;
284 /* NOTREACHED */
287 static pcap_t *pd;
289 extern int optind;
290 extern int opterr;
291 extern char *optarg;
293 struct print_info {
294 if_printer printer;
297 struct dump_info {
298 char *WFileName;
299 pcap_t *pd;
300 pcap_dumper_t *p;
303 static void
304 show_dlts_and_exit(pcap_t *pd)
306 int n_dlts;
307 int *dlts = 0;
308 const char *dlt_name;
310 n_dlts = pcap_list_datalinks(pd, &dlts);
311 if (n_dlts < 0)
312 error("%s", pcap_geterr(pd));
313 else if (n_dlts == 0 || !dlts)
314 error("No data link types.");
316 (void) fprintf(stderr, "Data link types (use option -y to set):\n");
318 while (--n_dlts >= 0) {
319 dlt_name = pcap_datalink_val_to_name(dlts[n_dlts]);
320 if (dlt_name != NULL) {
321 (void) fprintf(stderr, " %s (%s)", dlt_name,
322 pcap_datalink_val_to_description(dlts[n_dlts]));
325 * OK, does tcpdump handle that type?
327 if (lookup_printer(dlts[n_dlts]) == NULL)
328 (void) fprintf(stderr, " (not supported)");
329 putchar('\n');
330 } else {
331 (void) fprintf(stderr, " DLT %d (not supported)\n",
332 dlts[n_dlts]);
335 free(dlts);
336 exit(0);
340 * Set up flags that might or might not be supported depending on the
341 * version of libpcap we're using.
343 #ifdef WIN32
344 #define B_FLAG "B:"
345 #define B_FLAG_USAGE " [ -B size ]"
346 #else /* WIN32 */
347 #define B_FLAG
348 #define B_FLAG_USAGE
349 #endif /* WIN32 */
351 #ifdef HAVE_PCAP_FINDALLDEVS
352 #ifndef HAVE_PCAP_IF_T
353 #undef HAVE_PCAP_FINDALLDEVS
354 #endif
355 #endif
357 #ifdef HAVE_PCAP_FINDALLDEVS
358 #define D_FLAG "D"
359 #else
360 #define D_FLAG
361 #endif
363 #ifdef HAVE_PCAP_DUMP_FLUSH
364 #define U_FLAG "U"
365 #else
366 #define U_FLAG
367 #endif
369 #ifndef WIN32
370 /* Drop root privileges and chroot if necessary */
371 static void
372 droproot(const char *username, const char *chroot_dir)
374 struct passwd *pw = NULL;
376 if (chroot_dir && !username) {
377 fprintf(stderr, "tcpdump: Chroot without dropping root is insecure\n");
378 exit(1);
381 pw = getpwnam(username);
382 if (pw) {
383 if (chroot_dir) {
384 if (chroot(chroot_dir) != 0 || chdir ("/") != 0) {
385 fprintf(stderr, "tcpdump: Couldn't chroot/chdir to '%.64s': %s\n",
386 chroot_dir, pcap_strerror(errno));
387 exit(1);
390 if (initgroups(pw->pw_name, pw->pw_gid) != 0 ||
391 setgid(pw->pw_gid) != 0 || setuid(pw->pw_uid) != 0) {
392 fprintf(stderr, "tcpdump: Couldn't change to '%.32s' uid=%lu gid=%lu: %s\n",
393 username,
394 (unsigned long)pw->pw_uid,
395 (unsigned long)pw->pw_gid,
396 pcap_strerror(errno));
397 exit(1);
400 else {
401 fprintf(stderr, "tcpdump: Couldn't find user '%.32s'\n",
402 username);
403 exit(1);
406 #endif /* WIN32 */
408 static int
409 getWflagChars(int x)
411 int c = 0;
413 x -= 1;
414 while (x > 0) {
415 c += 1;
416 x /= 10;
419 return c;
423 static void
424 MakeFilename(char *buffer, char *orig_name, int cnt, int max_chars)
426 if (cnt == 0 && max_chars == 0)
427 strcpy(buffer, orig_name);
428 else
429 sprintf(buffer, "%s%0*d", orig_name, max_chars, cnt);
432 static int tcpdump_printf(netdissect_options *ndo _U_,
433 const char *fmt, ...)
436 va_list args;
437 int ret;
439 va_start(args, fmt);
440 ret=vfprintf(stdout, fmt, args);
441 va_end(args);
443 return ret;
447 main(int argc, char **argv)
449 register int cnt, op, i;
450 bpf_u_int32 localnet, netmask;
451 register char *cp, *infile, *cmdbuf, *device, *RFileName, *WFileName, *WFileNameAlt;
452 pcap_handler callback;
453 int type;
454 struct bpf_program fcode;
455 #ifndef WIN32
456 RETSIGTYPE (*oldhandler)(int);
457 #endif
458 struct print_info printinfo;
459 struct dump_info dumpinfo;
460 u_char *pcap_userdata;
461 char ebuf[PCAP_ERRBUF_SIZE];
462 char *username = NULL;
463 char *chroot_dir = NULL;
464 #ifdef HAVE_PCAP_FINDALLDEVS
465 pcap_if_t *devpointer;
466 int devnum;
467 #endif
468 int status;
469 #ifdef WIN32
470 u_int UserBufferSize = 1000000;
471 if(wsockinit() != 0) return 1;
472 #endif /* WIN32 */
474 gndo->ndo_Oflag=1;
475 gndo->ndo_Rflag=1;
476 gndo->ndo_dlt=-1;
477 gndo->ndo_default_print=ndo_default_print;
478 gndo->ndo_printf=tcpdump_printf;
479 gndo->ndo_error=ndo_error;
480 gndo->ndo_warning=ndo_warning;
481 gndo->ndo_snaplen = DEFAULT_SNAPLEN;
483 cnt = -1;
484 device = NULL;
485 infile = NULL;
486 RFileName = NULL;
487 WFileName = NULL;
488 if ((cp = strrchr(argv[0], '/')) != NULL)
489 program_name = cp + 1;
490 else
491 program_name = argv[0];
493 if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
494 error("%s", ebuf);
496 #ifdef LIBSMI
497 smiInit("tcpdump");
498 #endif
500 opterr = 0;
501 while (
502 (op = getopt(argc, argv, "aA" B_FLAG "c:C:d" D_FLAG "eE:fF:i:lLm:M:nNOpqr:Rs:StT:u" U_FLAG "vw:W:xXy:YZ:")) != -1)
503 switch (op) {
505 case 'a':
506 /* compatibility for old -a */
507 break;
509 case 'A':
510 ++Aflag;
511 break;
513 #ifdef WIN32
514 case 'B':
515 UserBufferSize = atoi(optarg)*1024;
516 if (UserBufferSize < 0)
517 error("invalid packet buffer size %s", optarg);
518 break;
519 #endif /* WIN32 */
521 case 'c':
522 cnt = atoi(optarg);
523 if (cnt <= 0)
524 error("invalid packet count %s", optarg);
525 break;
527 case 'C':
528 Cflag = atoi(optarg) * 1000000;
529 if (Cflag < 0)
530 error("invalid file size %s", optarg);
531 break;
533 case 'd':
534 ++dflag;
535 break;
537 #ifdef HAVE_PCAP_FINDALLDEVS
538 case 'D':
539 if (pcap_findalldevs(&devpointer, ebuf) < 0)
540 error("%s", ebuf);
541 else {
542 for (i = 0; devpointer != 0; i++) {
543 printf("%d.%s", i+1, devpointer->name);
544 if (devpointer->description != NULL)
545 printf(" (%s)", devpointer->description);
546 printf("\n");
547 devpointer = devpointer->next;
550 return 0;
551 #endif /* HAVE_PCAP_FINDALLDEVS */
553 case 'L':
554 Lflag++;
555 break;
557 case 'e':
558 ++eflag;
559 break;
561 case 'E':
562 #ifndef HAVE_LIBCRYPTO
563 warning("crypto code not compiled in");
564 #endif
565 gndo->ndo_espsecret = optarg;
566 break;
568 case 'f':
569 ++fflag;
570 break;
572 case 'F':
573 infile = optarg;
574 break;
576 case 'i':
577 if (optarg[0] == '0' && optarg[1] == 0)
578 error("Invalid adapter index");
580 #ifdef HAVE_PCAP_FINDALLDEVS
582 * If the argument is a number, treat it as
583 * an index into the list of adapters, as
584 * printed by "tcpdump -D".
586 * This should be OK on UNIX systems, as interfaces
587 * shouldn't have names that begin with digits.
588 * It can be useful on Windows, where more than
589 * one interface can have the same name.
591 if ((devnum = atoi(optarg)) != 0) {
592 if (devnum < 0)
593 error("Invalid adapter index");
595 if (pcap_findalldevs(&devpointer, ebuf) < 0)
596 error("%s", ebuf);
597 else {
598 for (i = 0; i < devnum-1; i++){
599 devpointer = devpointer->next;
600 if (devpointer == NULL)
601 error("Invalid adapter index");
604 device = devpointer->name;
605 break;
607 #endif /* HAVE_PCAP_FINDALLDEVS */
608 device = optarg;
609 break;
611 case 'l':
612 #ifdef WIN32
614 * _IOLBF is the same as _IOFBF in Microsoft's C
615 * libraries; the only alternative they offer
616 * is _IONBF.
618 * XXX - this should really be checking for MSVC++,
619 * not WIN32, if, for example, MinGW has its own
620 * C library that is more UNIX-compatible.
622 setvbuf(stdout, NULL, _IONBF, 0);
623 #else /* WIN32 */
624 #ifdef HAVE_SETLINEBUF
625 setlinebuf(stdout);
626 #else
627 setvbuf(stdout, NULL, _IOLBF, 0);
628 #endif
629 #endif /* WIN32 */
630 break;
632 case 'n':
633 ++nflag;
634 break;
636 case 'N':
637 ++Nflag;
638 break;
640 case 'm':
641 #ifdef LIBSMI
642 if (smiLoadModule(optarg) == 0) {
643 error("could not load MIB module %s", optarg);
645 sflag = 1;
646 #else
647 (void)fprintf(stderr, "%s: ignoring option `-m %s' ",
648 program_name, optarg);
649 (void)fprintf(stderr, "(no libsmi support)\n");
650 #endif
651 break;
653 case 'M':
654 /* TCP-MD5 shared secret */
655 #ifndef HAVE_LIBCRYPTO
656 warning("crypto code not compiled in");
657 #endif
658 tcpmd5secret = optarg;
659 break;
661 case 'O':
662 Oflag = 0;
663 break;
665 case 'p':
666 ++pflag;
667 break;
669 case 'q':
670 ++qflag;
671 ++suppress_default_print;
672 break;
674 case 'r':
675 RFileName = optarg;
676 break;
678 case 'R':
679 Rflag = 0;
680 break;
682 case 's': {
683 char *end;
685 snaplen = strtol(optarg, &end, 0);
686 if (optarg == end || *end != '\0'
687 || snaplen < 0 || snaplen > 65535)
688 error("invalid snaplen %s", optarg);
689 else if (snaplen == 0)
690 snaplen = 65535;
691 break;
694 case 'S':
695 ++Sflag;
696 break;
698 case 't':
699 ++tflag;
700 break;
702 case 'T':
703 if (strcasecmp(optarg, "vat") == 0)
704 packettype = PT_VAT;
705 else if (strcasecmp(optarg, "wb") == 0)
706 packettype = PT_WB;
707 else if (strcasecmp(optarg, "rpc") == 0)
708 packettype = PT_RPC;
709 else if (strcasecmp(optarg, "rtp") == 0)
710 packettype = PT_RTP;
711 else if (strcasecmp(optarg, "rtcp") == 0)
712 packettype = PT_RTCP;
713 else if (strcasecmp(optarg, "snmp") == 0)
714 packettype = PT_SNMP;
715 else if (strcasecmp(optarg, "cnfp") == 0)
716 packettype = PT_CNFP;
717 else if (strcasecmp(optarg, "tftp") == 0)
718 packettype = PT_TFTP;
719 else if (strcasecmp(optarg, "aodv") == 0)
720 packettype = PT_AODV;
721 else
722 error("unknown packet type `%s'", optarg);
723 break;
725 case 'u':
726 ++uflag;
727 break;
729 #ifdef HAVE_PCAP_DUMP_FLUSH
730 case 'U':
731 ++Uflag;
732 break;
733 #endif
735 case 'v':
736 ++vflag;
737 break;
739 case 'w':
740 WFileName = optarg;
741 break;
743 case 'W':
744 Wflag = atoi(optarg);
745 if (Wflag < 0)
746 error("invalid number of output files %s", optarg);
747 WflagChars = getWflagChars(Wflag);
748 break;
750 case 'x':
751 ++xflag;
752 ++suppress_default_print;
753 break;
755 case 'X':
756 ++Xflag;
757 ++suppress_default_print;
758 break;
760 case 'y':
761 gndo->ndo_dltname = optarg;
762 gndo->ndo_dlt =
763 pcap_datalink_name_to_val(gndo->ndo_dltname);
764 if (gndo->ndo_dlt < 0)
765 error("invalid data link type %s", gndo->ndo_dltname);
766 break;
768 #if defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG)
769 case 'Y':
771 /* Undocumented flag */
772 #ifdef HAVE_PCAP_DEBUG
773 extern int pcap_debug;
774 pcap_debug = 1;
775 #else
776 extern int yydebug;
777 yydebug = 1;
778 #endif
780 break;
781 #endif
782 case 'Z':
783 if (optarg) {
784 username = strdup(optarg);
786 else {
787 usage();
788 /* NOTREACHED */
790 break;
792 default:
793 usage();
794 /* NOTREACHED */
797 switch (tflag) {
799 case 0: /* Default */
800 case 4: /* Default + Date*/
801 thiszone = gmt2local(0);
802 break;
804 case 1: /* No time stamp */
805 case 2: /* Unix timeval style */
806 case 3: /* Microseconds since previous packet */
807 break;
809 default: /* Not supported */
810 error("only -t, -tt, -ttt, and -tttt are supported");
811 break;
814 #ifdef WITH_CHROOT
815 /* if run as root, prepare for chrooting */
816 if (getuid() == 0 || geteuid() == 0) {
817 /* future extensibility for cmd-line arguments */
818 if (!chroot_dir)
819 chroot_dir = WITH_CHROOT;
821 #endif
823 #ifdef WITH_USER
824 /* if run as root, prepare for dropping root privileges */
825 if (getuid() == 0 || geteuid() == 0) {
826 /* Run with '-Z root' to restore old behaviour */
827 if (!username)
828 username = WITH_USER;
830 #endif
832 if (RFileName != NULL) {
833 int dlt;
834 const char *dlt_name;
836 #ifndef WIN32
838 * We don't need network access, so relinquish any set-UID
839 * or set-GID privileges we have (if any).
841 * We do *not* want set-UID privileges when opening a
842 * trace file, as that might let the user read other
843 * people's trace files (especially if we're set-UID
844 * root).
846 if (setgid(getgid()) != 0 || setuid(getuid()) != 0 )
847 fprintf(stderr, "Warning: setgid/setuid failed !\n");
848 #endif /* WIN32 */
849 pd = pcap_open_offline(RFileName, ebuf);
850 if (pd == NULL)
851 error("%s", ebuf);
852 dlt = pcap_datalink(pd);
853 dlt_name = pcap_datalink_val_to_name(dlt);
854 if (dlt_name == NULL) {
855 fprintf(stderr, "reading from file %s, link-type %u\n",
856 RFileName, dlt);
857 } else {
858 fprintf(stderr,
859 "reading from file %s, link-type %s (%s)\n",
860 RFileName, dlt_name,
861 pcap_datalink_val_to_description(dlt));
863 localnet = 0;
864 netmask = 0;
865 if (fflag != 0)
866 error("-f and -r options are incompatible");
867 } else {
868 if (device == NULL) {
869 device = pcap_lookupdev(ebuf);
870 if (device == NULL)
871 error("%s", ebuf);
873 #ifdef WIN32
874 if(strlen(device) == 1) //we assume that an ASCII string is always longer than 1 char
875 { //a Unicode string has a \0 as second byte (so strlen() is 1)
876 fprintf(stderr, "%s: listening on %ws\n", program_name, device);
878 else
880 fprintf(stderr, "%s: listening on %s\n", program_name, device);
883 fflush(stderr);
884 #endif /* WIN32 */
885 *ebuf = '\0';
886 pd = pcap_open_live(device, snaplen, !pflag, 1000, ebuf);
887 if (pd == NULL)
888 error("%s", ebuf);
889 else if (*ebuf)
890 warning("%s", ebuf);
892 * Let user own process after socket has been opened.
894 #ifndef WIN32
895 if (setgid(getgid()) != 0 || setuid(getuid()) != 0)
896 fprintf(stderr, "Warning: setgid/setuid failed !\n");
897 #endif /* WIN32 */
898 #ifdef WIN32
899 if(UserBufferSize != 1000000)
900 if(pcap_setbuff(pd, UserBufferSize)==-1){
901 error("%s", pcap_geterr(pd));
903 #endif /* WIN32 */
904 if (Lflag)
905 show_dlts_and_exit(pd);
906 if (gndo->ndo_dlt >= 0) {
907 #ifdef HAVE_PCAP_SET_DATALINK
908 if (pcap_set_datalink(pd, gndo->ndo_dlt) < 0)
909 error("%s", pcap_geterr(pd));
910 #else
912 * We don't actually support changing the
913 * data link type, so we only let them
914 * set it to what it already is.
916 if (gndo->ndo_dlt != pcap_datalink(pd)) {
917 error("%s is not one of the DLTs supported by this device\n",
918 gndo->ndo_dltname);
920 #endif
921 (void)fprintf(stderr, "%s: data link type %s\n",
922 program_name, gndo->ndo_dltname);
923 (void)fflush(stderr);
925 i = pcap_snapshot(pd);
926 if (snaplen < i) {
927 warning("snaplen raised from %d to %d", snaplen, i);
928 snaplen = i;
930 if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
931 localnet = 0;
932 netmask = 0;
933 warning("%s", ebuf);
936 if (infile)
937 cmdbuf = read_infile(infile);
938 else
939 cmdbuf = copy_argv(&argv[optind]);
941 if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
942 error("%s", pcap_geterr(pd));
943 if (dflag) {
944 bpf_dump(&fcode, dflag);
945 pcap_close(pd);
946 exit(0);
948 init_addrtoname(localnet, netmask);
950 #ifndef WIN32
951 (void)setsignal(SIGPIPE, cleanup);
952 #endif /* WIN32 */
953 (void)setsignal(SIGTERM, cleanup);
954 (void)setsignal(SIGINT, cleanup);
955 /* Cooperate with nohup(1) */
956 #ifndef WIN32
957 if ((oldhandler = setsignal(SIGHUP, cleanup)) != SIG_DFL)
958 (void)setsignal(SIGHUP, oldhandler);
959 #endif /* WIN32 */
961 if (pcap_setfilter(pd, &fcode) < 0)
962 error("%s", pcap_geterr(pd));
963 if (WFileName) {
964 pcap_dumper_t *p;
966 WFileNameAlt = (char *)malloc(strlen(WFileName) + MAX_CFLAG_CHARS + 1);
967 if (WFileNameAlt == NULL)
968 error("malloc of WFileNameAlt");
969 MakeFilename(WFileNameAlt, WFileName, 0, WflagChars);
970 p = pcap_dump_open(pd, WFileNameAlt);
971 if (p == NULL)
972 error("%s", pcap_geterr(pd));
973 if (Cflag != 0) {
974 callback = dump_packet_and_trunc;
975 dumpinfo.WFileName = WFileName;
976 dumpinfo.pd = pd;
977 dumpinfo.p = p;
978 pcap_userdata = (u_char *)&dumpinfo;
979 } else {
980 callback = dump_packet;
981 pcap_userdata = (u_char *)p;
983 } else {
984 type = pcap_datalink(pd);
985 printinfo.printer = lookup_printer(type);
986 if (printinfo.printer == NULL) {
987 gndo->ndo_dltname = pcap_datalink_val_to_name(type);
988 if (gndo->ndo_dltname != NULL)
989 error("unsupported data link type %s",
990 gndo->ndo_dltname);
991 else
992 error("unsupported data link type %d", type);
994 callback = print_packet;
995 pcap_userdata = (u_char *)&printinfo;
997 #ifndef WIN32
999 * We cannot do this earlier, because we want to be able to open
1000 * the file (if done) for writing before giving up permissions.
1002 if (getuid() == 0 || geteuid() == 0) {
1003 if (username || chroot_dir)
1004 droproot(username, chroot_dir);
1006 #endif /* WIN32 */
1007 #ifdef SIGINFO
1008 (void)setsignal(SIGINFO, requestinfo);
1009 #endif
1011 if (vflag > 0 && WFileName) {
1013 * When capturing to a file, "-v" means tcpdump should,
1014 * every 10 secodns, "v"erbosely report the number of
1015 * packets captured.
1017 #ifdef USE_WIN32_MM_TIMER
1018 /* call verbose_stats_dump() each 1000 +/-100msec */
1019 timer_id = timeSetEvent(1000, 100, verbose_stats_dump, 0, TIME_PERIODIC);
1020 setvbuf(stderr, NULL, _IONBF, 0);
1021 #elif defined(HAVE_ALARM)
1022 (void)setsignal(SIGALRM, verbose_stats_dump);
1023 alarm(1);
1024 #endif
1027 #ifndef WIN32
1028 if (RFileName == NULL) {
1029 int dlt;
1030 const char *dlt_name;
1032 if (!vflag && !WFileName) {
1033 (void)fprintf(stderr,
1034 "%s: verbose output suppressed, use -v or -vv for full protocol decode\n",
1035 program_name);
1036 } else
1037 (void)fprintf(stderr, "%s: ", program_name);
1038 dlt = pcap_datalink(pd);
1039 dlt_name = pcap_datalink_val_to_name(dlt);
1040 if (dlt_name == NULL) {
1041 (void)fprintf(stderr, "listening on %s, link-type %u, capture size %u bytes\n",
1042 device, dlt, snaplen);
1043 } else {
1044 (void)fprintf(stderr, "listening on %s, link-type %s (%s), capture size %u bytes\n",
1045 device, dlt_name,
1046 pcap_datalink_val_to_description(dlt), snaplen);
1048 (void)fflush(stderr);
1050 #endif /* WIN32 */
1051 status = pcap_loop(pd, cnt, callback, pcap_userdata);
1052 if (WFileName == NULL) {
1054 * We're printing packets. Flush the printed output,
1055 * so it doesn't get intermingled with error output.
1057 if (status == -2) {
1059 * We got interrupted, so perhaps we didn't
1060 * manage to finish a line we were printing.
1061 * Print an extra newline, just in case.
1063 putchar('\n');
1065 (void)fflush(stdout);
1067 if (status == -1) {
1069 * Error. Report it.
1071 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
1072 program_name, pcap_geterr(pd));
1074 if (RFileName == NULL) {
1076 * We're doing a live capture. Report the capture
1077 * statistics.
1079 info(1);
1081 pcap_close(pd);
1082 exit(status == -1 ? 1 : 0);
1085 /* make a clean exit on interrupts */
1086 static RETSIGTYPE
1087 cleanup(int signo _U_)
1089 #ifdef USE_WIN32_MM_TIMER
1090 if (timer_id)
1091 timeKillEvent(timer_id);
1092 timer_id = 0;
1093 #elif defined(HAVE_ALARM)
1094 alarm(0);
1095 #endif
1097 #ifdef HAVE_PCAP_BREAKLOOP
1099 * We have "pcap_breakloop()"; use it, so that we do as little
1100 * as possible in the signal handler (it's probably not safe
1101 * to do anything with standard I/O streams in a signal handler -
1102 * the ANSI C standard doesn't say it is).
1104 pcap_breakloop(pd);
1105 #else
1107 * We don't have "pcap_breakloop()"; this isn't safe, but
1108 * it's the best we can do. Print the summary if we're
1109 * not reading from a savefile - i.e., if we're doing a
1110 * live capture - and exit.
1112 if (pd != NULL && pcap_file(pd) == NULL) {
1114 * We got interrupted, so perhaps we didn't
1115 * manage to finish a line we were printing.
1116 * Print an extra newline, just in case.
1118 putchar('\n');
1119 (void)fflush(stdout);
1120 info(1);
1122 exit(0);
1123 #endif
1126 static void
1127 info(register int verbose)
1129 struct pcap_stat stat;
1131 if (pcap_stats(pd, &stat) < 0) {
1132 (void)fprintf(stderr, "pcap_stats: %s\n", pcap_geterr(pd));
1133 return;
1136 if (!verbose)
1137 fprintf(stderr, "%s: ", program_name);
1139 (void)fprintf(stderr, "%u packets captured", packets_captured);
1140 if (!verbose)
1141 fputs(", ", stderr);
1142 else
1143 putc('\n', stderr);
1144 (void)fprintf(stderr, "%d packets received by filter", stat.ps_recv);
1145 if (!verbose)
1146 fputs(", ", stderr);
1147 else
1148 putc('\n', stderr);
1149 (void)fprintf(stderr, "%d packets dropped by kernel\n", stat.ps_drop);
1150 infoprint = 0;
1153 static void
1154 dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1156 struct dump_info *dump_info;
1157 char *name;
1159 ++packets_captured;
1161 ++infodelay;
1163 dump_info = (struct dump_info *)user;
1166 * XXX - this won't prevent capture files from getting
1167 * larger than Cflag - the last packet written to the
1168 * file could put it over Cflag.
1170 if (pcap_dump_ftell(dump_info->p) > Cflag) {
1172 * Close the current file and open a new one.
1174 pcap_dump_close(dump_info->p);
1175 Cflag_count++;
1176 if (Wflag > 0) {
1177 if (Cflag_count >= Wflag)
1178 Cflag_count = 0;
1179 } else {
1180 if (Cflag_count >= MAX_CFLAG)
1181 error("too many output files");
1183 name = (char *)malloc(strlen(dump_info->WFileName) + MAX_CFLAG_CHARS + 1);
1184 if (name == NULL)
1185 error("dump_packet_and_trunc: malloc");
1186 MakeFilename(name, dump_info->WFileName, Cflag_count, WflagChars);
1187 dump_info->p = pcap_dump_open(dump_info->pd, name);
1188 free(name);
1189 if (dump_info->p == NULL)
1190 error("%s", pcap_geterr(pd));
1193 pcap_dump((u_char *)dump_info->p, h, sp);
1194 #ifdef HAVE_PCAP_DUMP_FLUSH
1195 if (Uflag)
1196 pcap_dump_flush(dump_info->p);
1197 #endif
1199 --infodelay;
1200 if (infoprint)
1201 info(0);
1204 static void
1205 dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1207 ++packets_captured;
1209 ++infodelay;
1211 pcap_dump(user, h, sp);
1212 #ifdef HAVE_PCAP_DUMP_FLUSH
1213 if (Uflag)
1214 pcap_dump_flush((pcap_dumper_t *)user);
1215 #endif
1217 --infodelay;
1218 if (infoprint)
1219 info(0);
1222 static void
1223 print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1225 struct print_info *print_info;
1226 u_int hdrlen;
1228 ++packets_captured;
1230 ++infodelay;
1231 ts_print(&h->ts);
1233 print_info = (struct print_info *)user;
1236 * Some printers want to check that they're not walking off the
1237 * end of the packet.
1238 * Rather than pass it all the way down, we set this global.
1240 snapend = sp + h->caplen;
1242 hdrlen = (*print_info->printer)(h, sp);
1243 if (Xflag) {
1245 * Print the raw packet data in hex and ASCII.
1247 if (Xflag > 1) {
1249 * Include the link-layer header.
1251 hex_and_ascii_print("\n\t", sp, h->caplen);
1252 } else {
1254 * Don't include the link-layer header - and if
1255 * we have nothing past the link-layer header,
1256 * print nothing.
1258 if (h->caplen > hdrlen)
1259 hex_and_ascii_print("\n\t", sp + hdrlen,
1260 h->caplen - hdrlen);
1262 } else if (xflag) {
1264 * Print the raw packet data in hex.
1266 if (xflag > 1) {
1268 * Include the link-layer header.
1270 hex_print("\n\t", sp, h->caplen);
1271 } else {
1273 * Don't include the link-layer header - and if
1274 * we have nothing past the link-layer header,
1275 * print nothing.
1277 if (h->caplen > hdrlen)
1278 hex_print("\n\t", sp + hdrlen,
1279 h->caplen - hdrlen);
1281 } else if (Aflag) {
1283 * Print the raw packet data in ASCII.
1285 if (Aflag > 1) {
1287 * Include the link-layer header.
1289 ascii_print(sp, h->caplen);
1290 } else {
1292 * Don't include the link-layer header - and if
1293 * we have nothing past the link-layer header,
1294 * print nothing.
1296 if (h->caplen > hdrlen)
1297 ascii_print(sp + hdrlen, h->caplen - hdrlen);
1301 putchar('\n');
1303 --infodelay;
1304 if (infoprint)
1305 info(0);
1308 #ifdef WIN32
1310 * XXX - there should really be libpcap calls to get the version
1311 * number as a string (the string would be generated from #defines
1312 * at run time, so that it's not generated from string constants
1313 * in the library, as, on many UNIX systems, those constants would
1314 * be statically linked into the application executable image, and
1315 * would thus reflect the version of libpcap on the system on
1316 * which the application was *linked*, not the system on which it's
1317 * *running*.
1319 * That routine should be documented, unlike the "version[]"
1320 * string, so that UNIX vendors providing their own libpcaps
1321 * don't omit it (as a couple of vendors have...).
1323 * Packet.dll should perhaps also export a routine to return the
1324 * version number of the Packet.dll code, to supply the
1325 * "Wpcap_version" information on Windows.
1327 char WDversion[]="current-cvs.tcpdump.org";
1328 #if !defined(HAVE_GENERATED_VERSION)
1329 char version[]="current-cvs.tcpdump.org";
1330 #endif
1331 char pcap_version[]="current-cvs.tcpdump.org";
1332 char Wpcap_version[]="3.1";
1333 #endif
1336 * By default, print the specified data out in hex and ASCII.
1338 static void
1339 ndo_default_print(netdissect_options *ndo _U_, const u_char *bp, u_int length)
1341 hex_and_ascii_print("\n\t", bp, length); /* pass on lf and identation string */
1344 void
1345 default_print(const u_char *bp, u_int length)
1347 ndo_default_print(gndo, bp, length);
1350 #ifdef SIGINFO
1351 RETSIGTYPE requestinfo(int signo _U_)
1353 if (infodelay)
1354 ++infoprint;
1355 else
1356 info(0);
1358 #endif
1361 * Called once each second in verbose mode while dumping to file
1363 #ifdef USE_WIN32_MM_TIMER
1364 void CALLBACK verbose_stats_dump (UINT timer_id _U_, UINT msg _U_, DWORD_PTR arg _U_,
1365 DWORD_PTR dw1 _U_, DWORD_PTR dw2 _U_)
1367 struct pcap_stat stat;
1369 if (infodelay == 0 && pcap_stats(pd, &stat) >= 0)
1370 fprintf(stderr, "Got %u\r", packets_captured);
1372 #elif defined(HAVE_ALARM)
1373 static void verbose_stats_dump(int sig _U_)
1375 struct pcap_stat stat;
1377 if (infodelay == 0 && pcap_stats(pd, &stat) >= 0)
1378 fprintf(stderr, "Got %u\r", packets_captured);
1379 alarm(1);
1381 #endif
1383 static void
1384 usage(void)
1386 extern char version[];
1387 #ifndef HAVE_PCAP_LIB_VERSION
1388 #if defined(WIN32) || defined(HAVE_PCAP_VERSION)
1389 extern char pcap_version[];
1390 #else /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
1391 static char pcap_version[] = "unknown";
1392 #endif /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
1393 #endif /* HAVE_PCAP_LIB_VERSION */
1395 #ifdef HAVE_PCAP_LIB_VERSION
1396 #ifdef WIN32
1397 (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
1398 #else /* WIN32 */
1399 (void)fprintf(stderr, "%s version %s\n", program_name, version);
1400 #endif /* WIN32 */
1401 (void)fprintf(stderr, "%s\n",pcap_lib_version());
1402 #else /* HAVE_PCAP_LIB_VERSION */
1403 #ifdef WIN32
1404 (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
1405 (void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version);
1406 #else /* WIN32 */
1407 (void)fprintf(stderr, "%s version %s\n", program_name, version);
1408 (void)fprintf(stderr, "libpcap version %s\n", pcap_version);
1409 #endif /* WIN32 */
1410 #endif /* HAVE_PCAP_LIB_VERSION */
1411 (void)fprintf(stderr,
1412 "Usage: %s [-aAd" D_FLAG "eflLnNOpqRStu" U_FLAG "vxX]" B_FLAG_USAGE " [-c count] [ -C file_size ]\n", program_name);
1413 (void)fprintf(stderr,
1414 "\t\t[ -E algo:secret ] [ -F file ] [ -i interface ] [ -M secret ]\n");
1415 (void)fprintf(stderr,
1416 "\t\t[ -r file ] [ -s snaplen ] [ -T type ] [ -w file ]\n");
1417 (void)fprintf(stderr,
1418 "\t\t[ -W filecount ] [ -y datalinktype ] [ -Z user ]\n");
1419 (void)fprintf(stderr,
1420 "\t\t[ expression ]\n");
1421 exit(1);
1426 /* VARARGS */
1427 static void
1428 ndo_error(netdissect_options *ndo _U_, const char *fmt, ...)
1430 va_list ap;
1432 (void)fprintf(stderr, "%s: ", program_name);
1433 va_start(ap, fmt);
1434 (void)vfprintf(stderr, fmt, ap);
1435 va_end(ap);
1436 if (*fmt) {
1437 fmt += strlen(fmt);
1438 if (fmt[-1] != '\n')
1439 (void)fputc('\n', stderr);
1441 exit(1);
1442 /* NOTREACHED */
1445 /* VARARGS */
1446 static void
1447 ndo_warning(netdissect_options *ndo _U_, const char *fmt, ...)
1449 va_list ap;
1451 (void)fprintf(stderr, "%s: WARNING: ", program_name);
1452 va_start(ap, fmt);
1453 (void)vfprintf(stderr, fmt, ap);
1454 va_end(ap);
1455 if (*fmt) {
1456 fmt += strlen(fmt);
1457 if (fmt[-1] != '\n')
1458 (void)fputc('\n', stderr);