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";
32 static const char rcsid[] _U_ =
33 "@(#) $Header: /tcpdump/master/tcpdump/tcpdump.c,v 1.271.2.11 2008-09-25 21:50:04 guy Exp $ (LBL)";
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.
48 #include <tcpdump-stdinc.h>
53 extern int strcasecmp (const char *__s1, const char *__s2);
71 #include <sys/resource.h>
78 #include "netdissect.h"
79 #include "interface.h"
80 #include "addrtoname.h"
82 #include "setsignal.h"
83 #include "gmt2local.h"
84 #include "pcap-missing.h"
90 netdissect_options Gndo;
91 netdissect_options *gndo = &Gndo;
93 int dflag; /* print filter code */
94 int Lflag; /* list available data link types and exit */
95 char *zflag = NULL; /* compress each savefile using a specified command (like gzip or bzip2) */
102 int32_t thiszone; /* seconds offset from gmt to local time */
105 static RETSIGTYPE cleanup(int);
106 static RETSIGTYPE child_cleanup(int);
107 static void usage(void) __attribute__((noreturn));
108 static void show_dlts_and_exit(pcap_t *pd) __attribute__((noreturn));
110 static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
111 static void ndo_default_print(netdissect_options *, const u_char *, u_int);
112 static void dump_packet_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *);
113 static void dump_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
114 static void droproot(const char *, const char *);
115 static void ndo_error(netdissect_options *ndo, const char *fmt, ...);
116 static void ndo_warning(netdissect_options *ndo, const char *fmt, ...);
119 RETSIGTYPE requestinfo(int);
122 #if defined(USE_WIN32_MM_TIMER)
123 #include <MMsystem.h>
124 static UINT timer_id;
125 static void CALLBACK verbose_stats_dump(UINT, UINT, DWORD_PTR, DWORD_PTR, DWORD_PTR);
126 #elif defined(HAVE_ALARM)
127 static void verbose_stats_dump(int sig);
130 static void info(int);
131 static u_int packets_captured;
133 typedef u_int (*if_printer)(const struct pcap_pkthdr *, const u_char *);
140 static struct printer printers[] = {
141 { arcnet_if_print, DLT_ARCNET },
142 #ifdef DLT_ARCNET_LINUX
143 { arcnet_linux_if_print, DLT_ARCNET_LINUX },
145 { ether_if_print, DLT_EN10MB },
146 { token_if_print, DLT_IEEE802 },
148 { lane_if_print, DLT_LANE8023 },
151 { cip_if_print, DLT_CIP },
154 { cip_if_print, DLT_ATM_CLIP },
156 { sl_if_print, DLT_SLIP },
157 #ifdef DLT_SLIP_BSDOS
158 { sl_bsdos_if_print, DLT_SLIP_BSDOS },
160 { ppp_if_print, DLT_PPP },
161 #ifdef DLT_PPP_WITHDIRECTION
162 { ppp_if_print, DLT_PPP_WITHDIRECTION },
165 { ppp_bsdos_if_print, DLT_PPP_BSDOS },
167 { fddi_if_print, DLT_FDDI },
168 { null_if_print, DLT_NULL },
170 { null_if_print, DLT_LOOP },
172 { raw_if_print, DLT_RAW },
173 { atm_if_print, DLT_ATM_RFC1483 },
175 { chdlc_if_print, DLT_C_HDLC },
178 { chdlc_if_print, DLT_HDLC },
180 #ifdef DLT_PPP_SERIAL
181 { ppp_hdlc_if_print, DLT_PPP_SERIAL },
184 { pppoe_if_print, DLT_PPP_ETHER },
187 { sll_if_print, DLT_LINUX_SLL },
189 #ifdef DLT_IEEE802_11
190 { ieee802_11_if_print, DLT_IEEE802_11},
193 { ltalk_if_print, DLT_LTALK },
195 #if defined(DLT_PFLOG) && defined(HAVE_NET_PFVAR_H)
196 { pflog_if_print, DLT_PFLOG },
199 { fr_if_print, DLT_FR },
202 { fr_if_print, DLT_FRELAY },
205 { sunatm_if_print, DLT_SUNATM },
207 #ifdef DLT_IP_OVER_FC
208 { ipfc_if_print, DLT_IP_OVER_FC },
210 #ifdef DLT_PRISM_HEADER
211 { prism_if_print, DLT_PRISM_HEADER },
213 #ifdef DLT_IEEE802_11_RADIO
214 { ieee802_11_radio_if_print, DLT_IEEE802_11_RADIO },
217 { enc_if_print, DLT_ENC },
219 #ifdef DLT_SYMANTEC_FIREWALL
220 { symantec_if_print, DLT_SYMANTEC_FIREWALL },
222 #ifdef DLT_APPLE_IP_OVER_IEEE1394
223 { ap1394_if_print, DLT_APPLE_IP_OVER_IEEE1394 },
225 #ifdef DLT_IEEE802_11_RADIO_AVS
226 { ieee802_11_radio_avs_if_print, DLT_IEEE802_11_RADIO_AVS },
228 #ifdef DLT_JUNIPER_ATM1
229 { juniper_atm1_print, DLT_JUNIPER_ATM1 },
231 #ifdef DLT_JUNIPER_ATM2
232 { juniper_atm2_print, DLT_JUNIPER_ATM2 },
234 #ifdef DLT_JUNIPER_MFR
235 { juniper_mfr_print, DLT_JUNIPER_MFR },
237 #ifdef DLT_JUNIPER_MLFR
238 { juniper_mlfr_print, DLT_JUNIPER_MLFR },
240 #ifdef DLT_JUNIPER_MLPPP
241 { juniper_mlppp_print, DLT_JUNIPER_MLPPP },
243 #ifdef DLT_JUNIPER_PPPOE
244 { juniper_pppoe_print, DLT_JUNIPER_PPPOE },
246 #ifdef DLT_JUNIPER_PPPOE_ATM
247 { juniper_pppoe_atm_print, DLT_JUNIPER_PPPOE_ATM },
249 #ifdef DLT_JUNIPER_GGSN
250 { juniper_ggsn_print, DLT_JUNIPER_GGSN },
252 #ifdef DLT_JUNIPER_ES
253 { juniper_es_print, DLT_JUNIPER_ES },
255 #ifdef DLT_JUNIPER_MONITOR
256 { juniper_monitor_print, DLT_JUNIPER_MONITOR },
258 #ifdef DLT_JUNIPER_SERVICES
259 { juniper_services_print, DLT_JUNIPER_SERVICES },
261 #ifdef DLT_JUNIPER_ETHER
262 { juniper_ether_print, DLT_JUNIPER_ETHER },
264 #ifdef DLT_JUNIPER_PPP
265 { juniper_ppp_print, DLT_JUNIPER_PPP },
267 #ifdef DLT_JUNIPER_FRELAY
268 { juniper_frelay_print, DLT_JUNIPER_FRELAY },
270 #ifdef DLT_JUNIPER_CHDLC
271 { juniper_chdlc_print, DLT_JUNIPER_CHDLC },
274 { mfr_if_print, DLT_MFR },
276 #if defined(DLT_BLUETOOTH_HCI_H4_WITH_PHDR) && defined(HAVE_PCAP_BLUETOOTH_H)
277 { bt_if_print, DLT_BLUETOOTH_HCI_H4_WITH_PHDR},
283 lookup_printer(int type)
287 for (p = printers; p->f; ++p)
307 char *CurrentFileName;
313 show_dlts_and_exit(pcap_t *pd)
317 const char *dlt_name;
319 n_dlts = pcap_list_datalinks(pd, &dlts);
321 error("%s", pcap_geterr(pd));
322 else if (n_dlts == 0 || !dlts)
323 error("No data link types.");
325 (void) fprintf(stderr, "Data link types (use option -y to set):\n");
327 while (--n_dlts >= 0) {
328 dlt_name = pcap_datalink_val_to_name(dlts[n_dlts]);
329 if (dlt_name != NULL) {
330 (void) fprintf(stderr, " %s (%s)", dlt_name,
331 pcap_datalink_val_to_description(dlts[n_dlts]));
334 * OK, does tcpdump handle that type?
336 if (lookup_printer(dlts[n_dlts]) == NULL)
337 (void) fprintf(stderr, " (printing not supported)");
340 (void) fprintf(stderr, " DLT %d (printing not supported)\n",
349 * Set up flags that might or might not be supported depending on the
350 * version of libpcap we're using.
352 #if defined(HAVE_PCAP_CREATE) || defined(WIN32)
354 #define B_FLAG_USAGE " [ -B size ]"
355 #else /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
358 #endif /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
360 #ifdef HAVE_PCAP_CREATE
362 #else /* HAVE_PCAP_CREATE */
364 #endif /* HAVE_PCAP_CREATE */
366 #ifdef HAVE_PCAP_FINDALLDEVS
367 #ifndef HAVE_PCAP_IF_T
368 #undef HAVE_PCAP_FINDALLDEVS
372 #ifdef HAVE_PCAP_FINDALLDEVS
378 #ifdef HAVE_PCAP_DUMP_FLUSH
385 /* Drop root privileges and chroot if necessary */
387 droproot(const char *username, const char *chroot_dir)
389 struct passwd *pw = NULL;
391 if (chroot_dir && !username) {
392 fprintf(stderr, "tcpdump: Chroot without dropping root is insecure\n");
396 pw = getpwnam(username);
399 if (chroot(chroot_dir) != 0 || chdir ("/") != 0) {
400 fprintf(stderr, "tcpdump: Couldn't chroot/chdir to '%.64s': %s\n",
401 chroot_dir, pcap_strerror(errno));
405 if (initgroups(pw->pw_name, pw->pw_gid) != 0 ||
406 setgid(pw->pw_gid) != 0 || setuid(pw->pw_uid) != 0) {
407 fprintf(stderr, "tcpdump: Couldn't change to '%.32s' uid=%lu gid=%lu: %s\n",
409 (unsigned long)pw->pw_uid,
410 (unsigned long)pw->pw_gid,
411 pcap_strerror(errno));
416 fprintf(stderr, "tcpdump: Couldn't find user '%.32s'\n",
439 MakeFilename(char *buffer, char *orig_name, int cnt, int max_chars)
441 char *filename = malloc(NAME_MAX + 1);
443 /* Process with strftime if Gflag is set. */
447 /* Convert Gflag_time to a usable format */
448 if ((local_tm = localtime(&Gflag_time)) == NULL) {
449 error("MakeTimedFilename: localtime");
452 /* There's no good way to detect an error in strftime since a return
453 * value of 0 isn't necessarily failure.
455 strftime(filename, NAME_MAX, orig_name, local_tm);
457 strncpy(filename, orig_name, NAME_MAX);
460 if (cnt == 0 && max_chars == 0)
461 strncpy(buffer, filename, NAME_MAX + 1);
463 if (snprintf(buffer, NAME_MAX + 1, "%s%0*d", filename, max_chars, cnt) > NAME_MAX)
464 /* Report an error if the filename is too large */
465 error("too many output files or filename is too long (> %d)", NAME_MAX);
469 static int tcpdump_printf(netdissect_options *ndo _U_,
470 const char *fmt, ...)
477 ret=vfprintf(stdout, fmt, args);
484 main(int argc, char **argv)
486 register int cnt, op, i;
487 bpf_u_int32 localnet, netmask;
488 register char *cp, *infile, *cmdbuf, *device, *RFileName, *WFileName;
489 pcap_handler callback;
491 struct bpf_program fcode;
493 RETSIGTYPE (*oldhandler)(int);
495 struct print_info printinfo;
496 struct dump_info dumpinfo;
497 u_char *pcap_userdata;
498 char ebuf[PCAP_ERRBUF_SIZE];
499 char *username = NULL;
500 char *chroot_dir = NULL;
501 #ifdef HAVE_PCAP_FINDALLDEVS
502 pcap_if_t *devpointer;
507 if(wsockinit() != 0) return 1;
513 gndo->ndo_default_print=ndo_default_print;
514 gndo->ndo_printf=tcpdump_printf;
515 gndo->ndo_error=ndo_error;
516 gndo->ndo_warning=ndo_warning;
517 gndo->ndo_snaplen = DEFAULT_SNAPLEN;
524 if ((cp = strrchr(argv[0], '/')) != NULL)
525 program_name = cp + 1;
527 program_name = argv[0];
529 if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
538 (op = getopt(argc, argv, "aA" B_FLAG "c:C:d" D_FLAG "eE:fF:G:i:" I_FLAG "KlLm:M:nNOpqr:Rs:StT:u" U_FLAG "vw:W:xXy:Yz:Z:")) != -1)
542 /* compatibility for old -a */
549 #if defined(HAVE_PCAP_CREATE) || defined(WIN32)
551 Bflag = atoi(optarg)*1024;
553 error("invalid packet buffer size %s", optarg);
555 #endif /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
560 error("invalid packet count %s", optarg);
564 Cflag = atoi(optarg) * 1000000;
566 error("invalid file size %s", optarg);
573 #ifdef HAVE_PCAP_FINDALLDEVS
575 if (pcap_findalldevs(&devpointer, ebuf) < 0)
578 for (i = 0; devpointer != 0; i++) {
579 printf("%d.%s", i+1, devpointer->name);
580 if (devpointer->description != NULL)
581 printf(" (%s)", devpointer->description);
583 devpointer = devpointer->next;
587 #endif /* HAVE_PCAP_FINDALLDEVS */
598 #ifndef HAVE_LIBCRYPTO
599 warning("crypto code not compiled in");
601 gndo->ndo_espsecret = optarg;
613 Gflag = atoi(optarg);
615 error("invalid number of seconds %s", optarg);
617 /* We will create one file initially. */
620 /* Grab the current time for rotation use. */
621 if ((Gflag_time = time(NULL)) == (time_t)-1) {
622 error("main: can't get current time: %s",
623 pcap_strerror(errno));
628 if (optarg[0] == '0' && optarg[1] == 0)
629 error("Invalid adapter index");
631 #ifdef HAVE_PCAP_FINDALLDEVS
633 * If the argument is a number, treat it as
634 * an index into the list of adapters, as
635 * printed by "tcpdump -D".
637 * This should be OK on UNIX systems, as interfaces
638 * shouldn't have names that begin with digits.
639 * It can be useful on Windows, where more than
640 * one interface can have the same name.
642 if ((devnum = atoi(optarg)) != 0) {
644 error("Invalid adapter index");
646 if (pcap_findalldevs(&devpointer, ebuf) < 0)
649 for (i = 0; i < devnum-1; i++){
650 devpointer = devpointer->next;
651 if (devpointer == NULL)
652 error("Invalid adapter index");
655 device = devpointer->name;
658 #endif /* HAVE_PCAP_FINDALLDEVS */
662 #ifdef HAVE_PCAP_CREATE
666 #endif /* HAVE_PCAP_CREATE */
671 * _IOLBF is the same as _IOFBF in Microsoft's C
672 * libraries; the only alternative they offer
675 * XXX - this should really be checking for MSVC++,
676 * not WIN32, if, for example, MinGW has its own
677 * C library that is more UNIX-compatible.
679 setvbuf(stdout, NULL, _IONBF, 0);
681 #ifdef HAVE_SETLINEBUF
684 setvbuf(stdout, NULL, _IOLBF, 0);
695 if (smiLoadModule(optarg) == 0) {
696 error("could not load MIB module %s", optarg);
700 (void)fprintf(stderr, "%s: ignoring option `-m %s' ",
701 program_name, optarg);
702 (void)fprintf(stderr, "(no libsmi support)\n");
707 /* TCP-MD5 shared secret */
708 #ifndef HAVE_LIBCRYPTO
709 warning("crypto code not compiled in");
711 tcpmd5secret = optarg;
732 ++suppress_default_print;
746 snaplen = strtol(optarg, &end, 0);
747 if (optarg == end || *end != '\0'
748 || snaplen < 0 || snaplen > 65535)
749 error("invalid snaplen %s", optarg);
750 else if (snaplen == 0)
764 if (strcasecmp(optarg, "vat") == 0)
766 else if (strcasecmp(optarg, "wb") == 0)
768 else if (strcasecmp(optarg, "rpc") == 0)
770 else if (strcasecmp(optarg, "rtp") == 0)
772 else if (strcasecmp(optarg, "rtcp") == 0)
773 packettype = PT_RTCP;
774 else if (strcasecmp(optarg, "snmp") == 0)
775 packettype = PT_SNMP;
776 else if (strcasecmp(optarg, "cnfp") == 0)
777 packettype = PT_CNFP;
778 else if (strcasecmp(optarg, "tftp") == 0)
779 packettype = PT_TFTP;
780 else if (strcasecmp(optarg, "aodv") == 0)
781 packettype = PT_AODV;
783 error("unknown packet type `%s'", optarg);
790 #ifdef HAVE_PCAP_DUMP_FLUSH
805 Wflag = atoi(optarg);
807 error("invalid number of output files %s", optarg);
808 WflagChars = getWflagChars(Wflag);
813 ++suppress_default_print;
818 ++suppress_default_print;
822 gndo->ndo_dltname = optarg;
824 pcap_datalink_name_to_val(gndo->ndo_dltname);
825 if (gndo->ndo_dlt < 0)
826 error("invalid data link type %s", gndo->ndo_dltname);
829 #if defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG)
832 /* Undocumented flag */
833 #ifdef HAVE_PCAP_DEBUG
834 extern int pcap_debug;
845 zflag = strdup(optarg);
854 username = strdup(optarg);
869 case 0: /* Default */
870 case 4: /* Default + Date*/
871 thiszone = gmt2local(0);
874 case 1: /* No time stamp */
875 case 2: /* Unix timeval style */
876 case 3: /* Microseconds since previous packet */
877 case 5: /* Microseconds since first packet */
880 default: /* Not supported */
881 error("only -t, -tt, -ttt, -tttt and -ttttt are supported");
886 /* if run as root, prepare for chrooting */
887 if (getuid() == 0 || geteuid() == 0) {
888 /* future extensibility for cmd-line arguments */
890 chroot_dir = WITH_CHROOT;
895 /* if run as root, prepare for dropping root privileges */
896 if (getuid() == 0 || geteuid() == 0) {
897 /* Run with '-Z root' to restore old behaviour */
899 username = WITH_USER;
903 if (RFileName != NULL) {
905 const char *dlt_name;
909 * We don't need network access, so relinquish any set-UID
910 * or set-GID privileges we have (if any).
912 * We do *not* want set-UID privileges when opening a
913 * trace file, as that might let the user read other
914 * people's trace files (especially if we're set-UID
917 if (setgid(getgid()) != 0 || setuid(getuid()) != 0 )
918 fprintf(stderr, "Warning: setgid/setuid failed !\n");
920 pd = pcap_open_offline(RFileName, ebuf);
923 dlt = pcap_datalink(pd);
924 dlt_name = pcap_datalink_val_to_name(dlt);
925 if (dlt_name == NULL) {
926 fprintf(stderr, "reading from file %s, link-type %u\n",
930 "reading from file %s, link-type %s (%s)\n",
932 pcap_datalink_val_to_description(dlt));
937 error("-f and -r options are incompatible");
939 if (device == NULL) {
940 device = pcap_lookupdev(ebuf);
945 if(strlen(device) == 1) //we assume that an ASCII string is always longer than 1 char
946 { //a Unicode string has a \0 as second byte (so strlen() is 1)
947 fprintf(stderr, "%s: listening on %ws\n", program_name, device);
951 fprintf(stderr, "%s: listening on %s\n", program_name, device);
956 #ifdef HAVE_PCAP_CREATE
957 pd = pcap_create(device, ebuf);
960 status = pcap_set_snaplen(pd, snaplen);
962 error("%s: pcap_set_snaplen failed: %s",
963 device, pcap_statustostr(status));
964 status = pcap_set_promisc(pd, !pflag);
966 error("%s: pcap_set_promisc failed: %s",
967 device, pcap_statustostr(status));
969 status = pcap_set_rfmon(pd, 1);
971 error("%s: pcap_set_rfmon failed: %s",
972 device, pcap_statustostr(status));
974 status = pcap_set_timeout(pd, 1000);
976 error("%s: pcap_set_timeout failed: %s",
977 device, pcap_statustostr(status));
979 status = pcap_set_buffer_size(pd, Bflag);
981 error("%s: pcap_set_buffer_size failed: %s",
982 device, pcap_statustostr(status));
984 status = pcap_activate(pd);
987 * pcap_activate() failed.
989 cp = pcap_geterr(pd);
990 if (status == PCAP_ERROR)
992 else if ((status == PCAP_ERROR_NO_SUCH_DEVICE ||
993 status == PCAP_ERROR_PERM_DENIED) &&
995 error("%s: %s\n(%s)", device,
996 pcap_statustostr(status), cp);
998 error("%s: %s", device,
999 pcap_statustostr(status));
1000 } else if (status > 0) {
1002 * pcap_activate() succeeded, but it's warning us
1003 * of a problem it had.
1005 cp = pcap_geterr(pd);
1006 if (status == PCAP_WARNING)
1008 else if (status == PCAP_WARNING_PROMISC_NOTSUP &&
1010 warning("%s: %s\n(%s)", device,
1011 pcap_statustostr(status), cp);
1013 warning("%s: %s", device,
1014 pcap_statustostr(status));
1018 pd = pcap_open_live(device, snaplen, !pflag, 1000, ebuf);
1022 warning("%s", ebuf);
1023 #endif /* HAVE_PCAP_CREATE */
1025 * Let user own process after socket has been opened.
1028 if (setgid(getgid()) != 0 || setuid(getuid()) != 0)
1029 fprintf(stderr, "Warning: setgid/setuid failed !\n");
1031 #if !defined(HAVE_PCAP_CREATE) && defined(WIN32)
1033 if(pcap_setbuff(pd, Bflag)==-1){
1034 error("%s", pcap_geterr(pd));
1036 #endif /* !defined(HAVE_PCAP_CREATE) && defined(WIN32) */
1038 show_dlts_and_exit(pd);
1039 if (gndo->ndo_dlt >= 0) {
1040 #ifdef HAVE_PCAP_SET_DATALINK
1041 if (pcap_set_datalink(pd, gndo->ndo_dlt) < 0)
1042 error("%s", pcap_geterr(pd));
1045 * We don't actually support changing the
1046 * data link type, so we only let them
1047 * set it to what it already is.
1049 if (gndo->ndo_dlt != pcap_datalink(pd)) {
1050 error("%s is not one of the DLTs supported by this device\n",
1054 (void)fprintf(stderr, "%s: data link type %s\n",
1055 program_name, gndo->ndo_dltname);
1056 (void)fflush(stderr);
1058 i = pcap_snapshot(pd);
1060 warning("snaplen raised from %d to %d", snaplen, i);
1063 if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
1066 warning("%s", ebuf);
1070 cmdbuf = read_infile(infile);
1072 cmdbuf = copy_argv(&argv[optind]);
1074 if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
1075 error("%s", pcap_geterr(pd));
1077 bpf_dump(&fcode, dflag);
1081 init_addrtoname(localnet, netmask);
1085 (void)setsignal(SIGPIPE, cleanup);
1086 (void)setsignal(SIGTERM, cleanup);
1087 (void)setsignal(SIGINT, cleanup);
1088 (void)setsignal(SIGCHLD, child_cleanup);
1090 /* Cooperate with nohup(1) */
1092 if ((oldhandler = setsignal(SIGHUP, cleanup)) != SIG_DFL)
1093 (void)setsignal(SIGHUP, oldhandler);
1096 if (pcap_setfilter(pd, &fcode) < 0)
1097 error("%s", pcap_geterr(pd));
1100 /* Do not exceed the default NAME_MAX for files. */
1101 dumpinfo.CurrentFileName = (char *)malloc(NAME_MAX + 1);
1103 if (dumpinfo.CurrentFileName == NULL)
1104 error("malloc of dumpinfo.CurrentFileName");
1106 /* We do not need numbering for dumpfiles if Cflag isn't set. */
1108 MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, WflagChars);
1110 MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, 0);
1112 p = pcap_dump_open(pd, dumpinfo.CurrentFileName);
1114 error("%s", pcap_geterr(pd));
1115 if (Cflag != 0 || Gflag != 0) {
1116 callback = dump_packet_and_trunc;
1117 dumpinfo.WFileName = WFileName;
1120 pcap_userdata = (u_char *)&dumpinfo;
1122 callback = dump_packet;
1123 pcap_userdata = (u_char *)p;
1126 type = pcap_datalink(pd);
1127 printinfo.printer = lookup_printer(type);
1128 if (printinfo.printer == NULL) {
1129 gndo->ndo_dltname = pcap_datalink_val_to_name(type);
1130 if (gndo->ndo_dltname != NULL)
1131 error("unsupported data link type %s",
1134 error("unsupported data link type %d", type);
1136 callback = print_packet;
1137 pcap_userdata = (u_char *)&printinfo;
1141 * We cannot do this earlier, because we want to be able to open
1142 * the file (if done) for writing before giving up permissions.
1144 if (getuid() == 0 || geteuid() == 0) {
1145 if (username || chroot_dir)
1146 droproot(username, chroot_dir);
1151 * We can't get statistics when reading from a file rather
1152 * than capturing from a device.
1154 if (RFileName == NULL)
1155 (void)setsignal(SIGINFO, requestinfo);
1158 if (vflag > 0 && WFileName) {
1160 * When capturing to a file, "-v" means tcpdump should,
1161 * every 10 secodns, "v"erbosely report the number of
1164 #ifdef USE_WIN32_MM_TIMER
1165 /* call verbose_stats_dump() each 1000 +/-100msec */
1166 timer_id = timeSetEvent(1000, 100, verbose_stats_dump, 0, TIME_PERIODIC);
1167 setvbuf(stderr, NULL, _IONBF, 0);
1168 #elif defined(HAVE_ALARM)
1169 (void)setsignal(SIGALRM, verbose_stats_dump);
1175 if (RFileName == NULL) {
1177 const char *dlt_name;
1179 if (!vflag && !WFileName) {
1180 (void)fprintf(stderr,
1181 "%s: verbose output suppressed, use -v or -vv for full protocol decode\n",
1184 (void)fprintf(stderr, "%s: ", program_name);
1185 dlt = pcap_datalink(pd);
1186 dlt_name = pcap_datalink_val_to_name(dlt);
1187 if (dlt_name == NULL) {
1188 (void)fprintf(stderr, "listening on %s, link-type %u, capture size %u bytes\n",
1189 device, dlt, snaplen);
1191 (void)fprintf(stderr, "listening on %s, link-type %s (%s), capture size %u bytes\n",
1193 pcap_datalink_val_to_description(dlt), snaplen);
1195 (void)fflush(stderr);
1198 status = pcap_loop(pd, cnt, callback, pcap_userdata);
1199 if (WFileName == NULL) {
1201 * We're printing packets. Flush the printed output,
1202 * so it doesn't get intermingled with error output.
1206 * We got interrupted, so perhaps we didn't
1207 * manage to finish a line we were printing.
1208 * Print an extra newline, just in case.
1212 (void)fflush(stdout);
1218 (void)fprintf(stderr, "%s: pcap_loop: %s\n",
1219 program_name, pcap_geterr(pd));
1221 if (RFileName == NULL) {
1223 * We're doing a live capture. Report the capture
1229 exit(status == -1 ? 1 : 0);
1232 /* make a clean exit on interrupts */
1234 cleanup(int signo _U_)
1236 #ifdef USE_WIN32_MM_TIMER
1238 timeKillEvent(timer_id);
1240 #elif defined(HAVE_ALARM)
1244 #ifdef HAVE_PCAP_BREAKLOOP
1246 * We have "pcap_breakloop()"; use it, so that we do as little
1247 * as possible in the signal handler (it's probably not safe
1248 * to do anything with standard I/O streams in a signal handler -
1249 * the ANSI C standard doesn't say it is).
1254 * We don't have "pcap_breakloop()"; this isn't safe, but
1255 * it's the best we can do. Print the summary if we're
1256 * not reading from a savefile - i.e., if we're doing a
1257 * live capture - and exit.
1259 if (pd != NULL && pcap_file(pd) == NULL) {
1261 * We got interrupted, so perhaps we didn't
1262 * manage to finish a line we were printing.
1263 * Print an extra newline, just in case.
1266 (void)fflush(stdout);
1274 On windows, we do not use a fork, so we do not care less about
1275 waiting a child processes to die
1279 child_cleanup(int signo _U_)
1286 info(register int verbose)
1288 struct pcap_stat stat;
1290 if (pcap_stats(pd, &stat) < 0) {
1291 (void)fprintf(stderr, "pcap_stats: %s\n", pcap_geterr(pd));
1297 fprintf(stderr, "%s: ", program_name);
1299 (void)fprintf(stderr, "%u packets captured", packets_captured);
1301 fputs(", ", stderr);
1304 (void)fprintf(stderr, "%d packets received by filter", stat.ps_recv);
1306 fputs(", ", stderr);
1309 (void)fprintf(stderr, "%d packets dropped by kernel\n", stat.ps_drop);
1315 compress_savefile(const char *filename)
1320 * Set to lowest priority so that this doesn't disturb the capture
1323 setpriority(PRIO_PROCESS, 0, NZERO - 1);
1325 setpriority(PRIO_PROCESS, 0, 19);
1327 if (execlp(zflag, zflag, filename, NULL) == -1)
1329 "compress_savefile:execlp(%s, %s): %s\n",
1336 compress_savefile(const char *filename)
1339 "compress_savefile failed. Functionality not implemented under windows\n");
1344 dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1346 struct dump_info *dump_info;
1352 dump_info = (struct dump_info *)user;
1355 * XXX - this won't force the file to rotate on the specified time
1356 * boundary, but it will rotate on the first packet received after the
1357 * specified Gflag number of seconds. Note: if a Gflag time boundary
1358 * and a Cflag size boundary coincide, the time rotation will occur
1359 * first thereby cancelling the Cflag boundary (since the file should
1363 /* Check if it is time to rotate */
1366 /* Get the current time */
1367 if ((t = time(NULL)) == (time_t)-1) {
1368 error("dump_and_trunc_packet: can't get current_time: %s",
1369 pcap_strerror(errno));
1373 /* If the time is greater than the specified window, rotate */
1374 if (t - Gflag_time >= Gflag) {
1375 /* Update the Gflag_time */
1377 /* Update Gflag_count */
1380 * Close the current file and open a new one.
1382 pcap_dump_close(dump_info->p);
1385 * Compress the file we just closed, if the user asked for it
1388 compress_savefile(dump_info->CurrentFileName);
1391 * Check to see if we've exceeded the Wflag (when
1394 if (Cflag == 0 && Wflag > 0 && Gflag_count >= Wflag) {
1395 (void)fprintf(stderr, "Maximum file limit reached: %d\n",
1400 if (dump_info->CurrentFileName != NULL)
1401 free(dump_info->CurrentFileName);
1402 /* Allocate space for max filename + \0. */
1403 dump_info->CurrentFileName = (char *)malloc(NAME_MAX + 1);
1404 if (dump_info->CurrentFileName == NULL)
1405 error("dump_packet_and_trunc: malloc");
1407 * This is always the first file in the Cflag
1409 * We also don't need numbering if Cflag is not set.
1412 MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0,
1415 MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0, 0);
1417 dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
1418 if (dump_info->p == NULL)
1419 error("%s", pcap_geterr(pd));
1424 * XXX - this won't prevent capture files from getting
1425 * larger than Cflag - the last packet written to the
1426 * file could put it over Cflag.
1428 if (Cflag != 0 && pcap_dump_ftell(dump_info->p) > Cflag) {
1430 * Close the current file and open a new one.
1432 pcap_dump_close(dump_info->p);
1435 * Compress the file we just closed, if the user asked for it
1438 compress_savefile(dump_info->CurrentFileName);
1442 if (Cflag_count >= Wflag)
1445 if (dump_info->CurrentFileName != NULL)
1446 free(dump_info->CurrentFileName);
1447 dump_info->CurrentFileName = (char *)malloc(NAME_MAX + 1);
1448 if (dump_info->CurrentFileName == NULL)
1449 error("dump_packet_and_trunc: malloc");
1450 MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, Cflag_count, WflagChars);
1451 dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
1452 if (dump_info->p == NULL)
1453 error("%s", pcap_geterr(pd));
1456 pcap_dump((u_char *)dump_info->p, h, sp);
1457 #ifdef HAVE_PCAP_DUMP_FLUSH
1459 pcap_dump_flush(dump_info->p);
1468 dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1474 pcap_dump(user, h, sp);
1475 #ifdef HAVE_PCAP_DUMP_FLUSH
1477 pcap_dump_flush((pcap_dumper_t *)user);
1486 print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
1488 struct print_info *print_info;
1496 print_info = (struct print_info *)user;
1499 * Some printers want to check that they're not walking off the
1500 * end of the packet.
1501 * Rather than pass it all the way down, we set this global.
1503 snapend = sp + h->caplen;
1505 hdrlen = (*print_info->printer)(h, sp);
1508 * Print the raw packet data in hex and ASCII.
1512 * Include the link-layer header.
1514 hex_and_ascii_print("\n\t", sp, h->caplen);
1517 * Don't include the link-layer header - and if
1518 * we have nothing past the link-layer header,
1521 if (h->caplen > hdrlen)
1522 hex_and_ascii_print("\n\t", sp + hdrlen,
1523 h->caplen - hdrlen);
1527 * Print the raw packet data in hex.
1531 * Include the link-layer header.
1533 hex_print("\n\t", sp, h->caplen);
1536 * Don't include the link-layer header - and if
1537 * we have nothing past the link-layer header,
1540 if (h->caplen > hdrlen)
1541 hex_print("\n\t", sp + hdrlen,
1542 h->caplen - hdrlen);
1546 * Print the raw packet data in ASCII.
1550 * Include the link-layer header.
1552 ascii_print(sp, h->caplen);
1555 * Don't include the link-layer header - and if
1556 * we have nothing past the link-layer header,
1559 if (h->caplen > hdrlen)
1560 ascii_print(sp + hdrlen, h->caplen - hdrlen);
1573 * XXX - there should really be libpcap calls to get the version
1574 * number as a string (the string would be generated from #defines
1575 * at run time, so that it's not generated from string constants
1576 * in the library, as, on many UNIX systems, those constants would
1577 * be statically linked into the application executable image, and
1578 * would thus reflect the version of libpcap on the system on
1579 * which the application was *linked*, not the system on which it's
1582 * That routine should be documented, unlike the "version[]"
1583 * string, so that UNIX vendors providing their own libpcaps
1584 * don't omit it (as a couple of vendors have...).
1586 * Packet.dll should perhaps also export a routine to return the
1587 * version number of the Packet.dll code, to supply the
1588 * "Wpcap_version" information on Windows.
1590 char WDversion[]="current-cvs.tcpdump.org";
1591 #if !defined(HAVE_GENERATED_VERSION)
1592 char version[]="current-cvs.tcpdump.org";
1594 char pcap_version[]="current-cvs.tcpdump.org";
1595 char Wpcap_version[]="3.1";
1599 * By default, print the specified data out in hex and ASCII.
1602 ndo_default_print(netdissect_options *ndo _U_, const u_char *bp, u_int length)
1604 hex_and_ascii_print("\n\t", bp, length); /* pass on lf and identation string */
1608 default_print(const u_char *bp, u_int length)
1610 ndo_default_print(gndo, bp, length);
1614 RETSIGTYPE requestinfo(int signo _U_)
1624 * Called once each second in verbose mode while dumping to file
1626 #ifdef USE_WIN32_MM_TIMER
1627 void CALLBACK verbose_stats_dump (UINT timer_id _U_, UINT msg _U_, DWORD_PTR arg _U_,
1628 DWORD_PTR dw1 _U_, DWORD_PTR dw2 _U_)
1630 struct pcap_stat stat;
1632 if (infodelay == 0 && pcap_stats(pd, &stat) >= 0)
1633 fprintf(stderr, "Got %u\r", packets_captured);
1635 #elif defined(HAVE_ALARM)
1636 static void verbose_stats_dump(int sig _U_)
1638 struct pcap_stat stat;
1640 if (infodelay == 0 && pcap_stats(pd, &stat) >= 0)
1641 fprintf(stderr, "Got %u\r", packets_captured);
1649 extern char version[];
1650 #ifndef HAVE_PCAP_LIB_VERSION
1651 #if defined(WIN32) || defined(HAVE_PCAP_VERSION)
1652 extern char pcap_version[];
1653 #else /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
1654 static char pcap_version[] = "unknown";
1655 #endif /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
1656 #endif /* HAVE_PCAP_LIB_VERSION */
1658 #ifdef HAVE_PCAP_LIB_VERSION
1660 (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
1662 (void)fprintf(stderr, "%s version %s\n", program_name, version);
1664 (void)fprintf(stderr, "%s\n",pcap_lib_version());
1665 #else /* HAVE_PCAP_LIB_VERSION */
1667 (void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
1668 (void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version);
1670 (void)fprintf(stderr, "%s version %s\n", program_name, version);
1671 (void)fprintf(stderr, "libpcap version %s\n", pcap_version);
1673 #endif /* HAVE_PCAP_LIB_VERSION */
1674 (void)fprintf(stderr,
1675 "Usage: %s [-aAd" D_FLAG "ef" I_FLAG "KlLnNOpqRStu" U_FLAG "vxX]" B_FLAG_USAGE " [ -c count ]\n", program_name);
1676 (void)fprintf(stderr,
1677 "\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n");
1678 (void)fprintf(stderr,
1679 "\t\t[ -i interface ] [ -M secret ] [ -r file ]\n");
1680 (void)fprintf(stderr,
1681 "\t\t[ -s snaplen ] [ -T type ] [ -w file ] [ -W filecount ]\n");
1682 (void)fprintf(stderr,
1683 "\t\t[ -y datalinktype ] [ -z command ] [ -Z user ]\n");
1684 (void)fprintf(stderr,
1685 "\t\t[ expression ]\n");
1693 ndo_error(netdissect_options *ndo _U_, const char *fmt, ...)
1697 (void)fprintf(stderr, "%s: ", program_name);
1699 (void)vfprintf(stderr, fmt, ap);
1703 if (fmt[-1] != '\n')
1704 (void)fputc('\n', stderr);
1712 ndo_warning(netdissect_options *ndo _U_, const char *fmt, ...)
1716 (void)fprintf(stderr, "%s: WARNING: ", program_name);
1718 (void)vfprintf(stderr, fmt, ap);
1722 if (fmt[-1] != '\n')
1723 (void)fputc('\n', stderr);