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freebsd-skq/contrib/tcpdump/tcpdump.c
Robert Watson b881b8be1d Update most userspace consumers of capability.h to use capsicum.h instead. 
auditdistd is not updated as I will make the change upstream and then do a
vendor import sometime in the next week or two.

MFC after:	3 weeks
2014-03-16 11:04:44 +00:00

2341 lines
57 KiB
C
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/*
* Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that: (1) source code distributions
* retain the above copyright notice and this paragraph in its entirety, (2)
* distributions including binary code include the above copyright notice and
* this paragraph in its entirety in the documentation or other materials
* provided with the distribution, and (3) all advertising materials mentioning
* features or use of this software display the following acknowledgement:
* ``This product includes software developed by the University of California,
* Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
* the University nor the names of its contributors may be used to endorse
* or promote products derived from this software without specific prior
* written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*
* Support for splitting captures into multiple files with a maximum
* file size:
*
* Copyright (c) 2001
* Seth Webster <swebster@sst.ll.mit.edu>
*/
#ifndef lint
static const char copyright[] _U_ =
"@(#) Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 2000\n\
The Regents of the University of California. All rights reserved.\n";
static const char rcsid[] _U_ =
"@(#) $Header: /tcpdump/master/tcpdump/tcpdump.c,v 1.283 2008-09-25 21:45:50 guy Exp $ (LBL)";
#endif
/* $FreeBSD$ */
/*
* tcpdump - monitor tcp/ip traffic on an ethernet.
*
* First written in 1987 by Van Jacobson, Lawrence Berkeley Laboratory.
* Mercilessly hacked and occasionally improved since then via the
* combined efforts of Van, Steve McCanne and Craig Leres of LBL.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <tcpdump-stdinc.h>
#ifdef WIN32
#include "getopt.h"
#include "w32_fzs.h"
extern int strcasecmp (const char *__s1, const char *__s2);
extern int SIZE_BUF;
#define off_t long
#define uint UINT
#endif /* WIN32 */
#ifdef HAVE_SMI_H
#include <smi.h>
#endif
#include <pcap.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#ifdef __FreeBSD__
#include <sys/capsicum.h>
#include <sys/ioccom.h>
#include <sys/types.h>
#include <sys/sysctl.h>
#include <net/bpf.h>
#include <fcntl.h>
#include <libgen.h>
#ifdef HAVE_LIBCAPSICUM
#include <libcapsicum.h>
#include <libcapsicum_dns.h>
#include <libcapsicum_service.h>
#include <nv.h>
#endif /* HAVE_LIBCAPSICUM */
#endif /* __FreeBSD__ */
#ifndef WIN32
#include <sys/wait.h>
#include <sys/resource.h>
#include <pwd.h>
#include <grp.h>
#include <errno.h>
#endif /* WIN32 */
/* capabilities convinience library */
#ifdef HAVE_CAP_NG_H
#include <cap-ng.h>
#endif /* HAVE_CAP_NG_H */
#include "netdissect.h"
#include "interface.h"
#include "addrtoname.h"
#include "machdep.h"
#include "setsignal.h"
#include "gmt2local.h"
#include "pcap-missing.h"
#ifndef PATH_MAX
#define PATH_MAX 1024
#endif
#ifdef SIGINFO
#define SIGNAL_REQ_INFO SIGINFO
#elif SIGUSR1
#define SIGNAL_REQ_INFO SIGUSR1
#endif
netdissect_options Gndo;
netdissect_options *gndo = &Gndo;
static int dflag; /* print filter code */
static int Lflag; /* list available data link types and exit */
#ifdef HAVE_PCAP_SET_TSTAMP_TYPE
static int Jflag; /* list available time stamp types */
#endif
static char *zflag = NULL; /* compress each savefile using a specified command (like gzip or bzip2) */
static int infodelay;
static int infoprint;
char *program_name;
#ifdef HAVE_LIBCAPSICUM
cap_channel_t *capdns;
#endif
int32_t thiszone; /* seconds offset from gmt to local time */
/* Forwards */
static RETSIGTYPE cleanup(int);
static RETSIGTYPE child_cleanup(int);
static void usage(void) __attribute__((noreturn));
static void show_dlts_and_exit(const char *device, pcap_t *pd) __attribute__((noreturn));
static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
static void ndo_default_print(netdissect_options *, const u_char *, u_int);
static void dump_packet_and_trunc(u_char *, const struct pcap_pkthdr *, const u_char *);
static void dump_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
static void droproot(const char *, const char *);
static void ndo_error(netdissect_options *ndo, const char *fmt, ...)
__attribute__ ((noreturn, format (printf, 2, 3)));
static void ndo_warning(netdissect_options *ndo, const char *fmt, ...);
#ifdef SIGNAL_REQ_INFO
RETSIGTYPE requestinfo(int);
#endif
#if defined(USE_WIN32_MM_TIMER)
#include <MMsystem.h>
static UINT timer_id;
static void CALLBACK verbose_stats_dump(UINT, UINT, DWORD_PTR, DWORD_PTR, DWORD_PTR);
#elif defined(HAVE_ALARM)
static void verbose_stats_dump(int sig);
#endif
static void info(int);
static u_int packets_captured;
struct printer {
if_printer f;
int type;
};
struct ndo_printer {
if_ndo_printer f;
int type;
};
static struct printer printers[] = {
{ arcnet_if_print, DLT_ARCNET },
#ifdef DLT_ARCNET_LINUX
{ arcnet_linux_if_print, DLT_ARCNET_LINUX },
#endif
{ token_if_print, DLT_IEEE802 },
#ifdef DLT_LANE8023
{ lane_if_print, DLT_LANE8023 },
#endif
#ifdef DLT_CIP
{ cip_if_print, DLT_CIP },
#endif
#ifdef DLT_ATM_CLIP
{ cip_if_print, DLT_ATM_CLIP },
#endif
{ sl_if_print, DLT_SLIP },
#ifdef DLT_SLIP_BSDOS
{ sl_bsdos_if_print, DLT_SLIP_BSDOS },
#endif
{ ppp_if_print, DLT_PPP },
#ifdef DLT_PPP_WITHDIRECTION
{ ppp_if_print, DLT_PPP_WITHDIRECTION },
#endif
#ifdef DLT_PPP_BSDOS
{ ppp_bsdos_if_print, DLT_PPP_BSDOS },
#endif
{ fddi_if_print, DLT_FDDI },
{ null_if_print, DLT_NULL },
#ifdef DLT_LOOP
{ null_if_print, DLT_LOOP },
#endif
{ raw_if_print, DLT_RAW },
{ atm_if_print, DLT_ATM_RFC1483 },
#ifdef DLT_C_HDLC
{ chdlc_if_print, DLT_C_HDLC },
#endif
#ifdef DLT_HDLC
{ chdlc_if_print, DLT_HDLC },
#endif
#ifdef DLT_PPP_SERIAL
{ ppp_hdlc_if_print, DLT_PPP_SERIAL },
#endif
#ifdef DLT_PPP_ETHER
{ pppoe_if_print, DLT_PPP_ETHER },
#endif
#ifdef DLT_LINUX_SLL
{ sll_if_print, DLT_LINUX_SLL },
#endif
#ifdef DLT_IEEE802_11
{ ieee802_11_if_print, DLT_IEEE802_11},
#endif
#ifdef DLT_LTALK
{ ltalk_if_print, DLT_LTALK },
#endif
#if defined(DLT_PFLOG) && defined(HAVE_NET_PFVAR_H)
{ pflog_if_print, DLT_PFLOG },
#endif
#ifdef DLT_FR
{ fr_if_print, DLT_FR },
#endif
#ifdef DLT_FRELAY
{ fr_if_print, DLT_FRELAY },
#endif
#ifdef DLT_SUNATM
{ sunatm_if_print, DLT_SUNATM },
#endif
#ifdef DLT_IP_OVER_FC
{ ipfc_if_print, DLT_IP_OVER_FC },
#endif
#ifdef DLT_PRISM_HEADER
{ prism_if_print, DLT_PRISM_HEADER },
#endif
#ifdef DLT_IEEE802_11_RADIO
{ ieee802_11_radio_if_print, DLT_IEEE802_11_RADIO },
#endif
#ifdef DLT_ENC
{ enc_if_print, DLT_ENC },
#endif
#ifdef DLT_SYMANTEC_FIREWALL
{ symantec_if_print, DLT_SYMANTEC_FIREWALL },
#endif
#ifdef DLT_APPLE_IP_OVER_IEEE1394
{ ap1394_if_print, DLT_APPLE_IP_OVER_IEEE1394 },
#endif
#ifdef DLT_IEEE802_11_RADIO_AVS
{ ieee802_11_radio_avs_if_print, DLT_IEEE802_11_RADIO_AVS },
#endif
#ifdef DLT_JUNIPER_ATM1
{ juniper_atm1_print, DLT_JUNIPER_ATM1 },
#endif
#ifdef DLT_JUNIPER_ATM2
{ juniper_atm2_print, DLT_JUNIPER_ATM2 },
#endif
#ifdef DLT_JUNIPER_MFR
{ juniper_mfr_print, DLT_JUNIPER_MFR },
#endif
#ifdef DLT_JUNIPER_MLFR
{ juniper_mlfr_print, DLT_JUNIPER_MLFR },
#endif
#ifdef DLT_JUNIPER_MLPPP
{ juniper_mlppp_print, DLT_JUNIPER_MLPPP },
#endif
#ifdef DLT_JUNIPER_PPPOE
{ juniper_pppoe_print, DLT_JUNIPER_PPPOE },
#endif
#ifdef DLT_JUNIPER_PPPOE_ATM
{ juniper_pppoe_atm_print, DLT_JUNIPER_PPPOE_ATM },
#endif
#ifdef DLT_JUNIPER_GGSN
{ juniper_ggsn_print, DLT_JUNIPER_GGSN },
#endif
#ifdef DLT_JUNIPER_ES
{ juniper_es_print, DLT_JUNIPER_ES },
#endif
#ifdef DLT_JUNIPER_MONITOR
{ juniper_monitor_print, DLT_JUNIPER_MONITOR },
#endif
#ifdef DLT_JUNIPER_SERVICES
{ juniper_services_print, DLT_JUNIPER_SERVICES },
#endif
#ifdef DLT_JUNIPER_ETHER
{ juniper_ether_print, DLT_JUNIPER_ETHER },
#endif
#ifdef DLT_JUNIPER_PPP
{ juniper_ppp_print, DLT_JUNIPER_PPP },
#endif
#ifdef DLT_JUNIPER_FRELAY
{ juniper_frelay_print, DLT_JUNIPER_FRELAY },
#endif
#ifdef DLT_JUNIPER_CHDLC
{ juniper_chdlc_print, DLT_JUNIPER_CHDLC },
#endif
#ifdef DLT_MFR
{ mfr_if_print, DLT_MFR },
#endif
#if defined(DLT_BLUETOOTH_HCI_H4_WITH_PHDR) && defined(HAVE_PCAP_BLUETOOTH_H)
{ bt_if_print, DLT_BLUETOOTH_HCI_H4_WITH_PHDR},
#endif
#ifdef HAVE_PCAP_USB_H
#ifdef DLT_USB_LINUX
{ usb_linux_48_byte_print, DLT_USB_LINUX},
#endif /* DLT_USB_LINUX */
#ifdef DLT_USB_LINUX_MMAPPED
{ usb_linux_64_byte_print, DLT_USB_LINUX_MMAPPED},
#endif /* DLT_USB_LINUX_MMAPPED */
#endif /* HAVE_PCAP_USB_H */
#ifdef DLT_IPV4
{ raw_if_print, DLT_IPV4 },
#endif
#ifdef DLT_IPV6
{ raw_if_print, DLT_IPV6 },
#endif
{ NULL, 0 },
};
static struct ndo_printer ndo_printers[] = {
{ ether_if_print, DLT_EN10MB },
#ifdef DLT_IPNET
{ ipnet_if_print, DLT_IPNET },
#endif
#ifdef DLT_IEEE802_15_4
{ ieee802_15_4_if_print, DLT_IEEE802_15_4 },
#endif
#ifdef DLT_IEEE802_15_4_NOFCS
{ ieee802_15_4_if_print, DLT_IEEE802_15_4_NOFCS },
#endif
#ifdef DLT_PPI
{ ppi_if_print, DLT_PPI },
#endif
#ifdef DLT_NETANALYZER
{ netanalyzer_if_print, DLT_NETANALYZER },
#endif
#ifdef DLT_NETANALYZER_TRANSPARENT
{ netanalyzer_transparent_if_print, DLT_NETANALYZER_TRANSPARENT },
#endif
{ NULL, 0 },
};
if_printer
lookup_printer(int type)
{
struct printer *p;
for (p = printers; p->f; ++p)
if (type == p->type)
return p->f;
return NULL;
/* NOTREACHED */
}
if_ndo_printer
lookup_ndo_printer(int type)
{
struct ndo_printer *p;
for (p = ndo_printers; p->f; ++p)
if (type == p->type)
return p->f;
return NULL;
/* NOTREACHED */
}
static pcap_t *pd;
static int supports_monitor_mode;
extern int optind;
extern int opterr;
extern char *optarg;
struct print_info {
netdissect_options *ndo;
union {
if_printer printer;
if_ndo_printer ndo_printer;
} p;
int ndo_type;
};
struct dump_info {
char *WFileName;
char *CurrentFileName;
pcap_t *pd;
pcap_dumper_t *p;
#ifdef __FreeBSD__
int dirfd;
#endif
};
#ifdef HAVE_PCAP_SET_TSTAMP_TYPE
static void
show_tstamp_types_and_exit(const char *device, pcap_t *pd)
{
int n_tstamp_types;
int *tstamp_types = 0;
const char *tstamp_type_name;
int i;
n_tstamp_types = pcap_list_tstamp_types(pd, &tstamp_types);
if (n_tstamp_types < 0)
error("%s", pcap_geterr(pd));
if (n_tstamp_types == 0) {
fprintf(stderr, "Time stamp type cannot be set for %s\n",
device);
exit(0);
}
fprintf(stderr, "Time stamp types for %s (use option -j to set):\n",
device);
for (i = 0; i < n_tstamp_types; i++) {
tstamp_type_name = pcap_tstamp_type_val_to_name(tstamp_types[i]);
if (tstamp_type_name != NULL) {
(void) fprintf(stderr, " %s (%s)\n", tstamp_type_name,
pcap_tstamp_type_val_to_description(tstamp_types[i]));
} else {
(void) fprintf(stderr, " %d\n", tstamp_types[i]);
}
}
pcap_free_tstamp_types(tstamp_types);
exit(0);
}
#endif
static void
show_dlts_and_exit(const char *device, pcap_t *pd)
{
int n_dlts;
int *dlts = 0;
const char *dlt_name;
n_dlts = pcap_list_datalinks(pd, &dlts);
if (n_dlts < 0)
error("%s", pcap_geterr(pd));
else if (n_dlts == 0 || !dlts)
error("No data link types.");
/*
* If the interface is known to support monitor mode, indicate
* whether these are the data link types available when not in
* monitor mode, if -I wasn't specified, or when in monitor mode,
* when -I was specified (the link-layer types available in
* monitor mode might be different from the ones available when
* not in monitor mode).
*/
if (supports_monitor_mode)
(void) fprintf(stderr, "Data link types for %s %s (use option -y to set):\n",
device,
Iflag ? "when in monitor mode" : "when not in monitor mode");
else
(void) fprintf(stderr, "Data link types for %s (use option -y to set):\n",
device);
while (--n_dlts >= 0) {
dlt_name = pcap_datalink_val_to_name(dlts[n_dlts]);
if (dlt_name != NULL) {
(void) fprintf(stderr, " %s (%s)", dlt_name,
pcap_datalink_val_to_description(dlts[n_dlts]));
/*
* OK, does tcpdump handle that type?
*/
if (lookup_printer(dlts[n_dlts]) == NULL
&& lookup_ndo_printer(dlts[n_dlts]) == NULL)
(void) fprintf(stderr, " (printing not supported)");
fprintf(stderr, "\n");
} else {
(void) fprintf(stderr, " DLT %d (printing not supported)\n",
dlts[n_dlts]);
}
}
#ifdef HAVE_PCAP_FREE_DATALINKS
pcap_free_datalinks(dlts);
#endif
exit(0);
}
/*
* Set up flags that might or might not be supported depending on the
* version of libpcap we're using.
*/
#if defined(HAVE_PCAP_CREATE) || defined(WIN32)
#define B_FLAG "B:"
#define B_FLAG_USAGE " [ -B size ]"
#else /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
#define B_FLAG
#define B_FLAG_USAGE
#endif /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
#ifdef HAVE_PCAP_CREATE
#define I_FLAG "I"
#else /* HAVE_PCAP_CREATE */
#define I_FLAG
#endif /* HAVE_PCAP_CREATE */
#ifdef HAVE_PCAP_SET_TSTAMP_TYPE
#define j_FLAG "j:"
#define j_FLAG_USAGE " [ -j tstamptype ]"
#define J_FLAG "J"
#else /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */
#define j_FLAG
#define j_FLAG_USAGE
#define J_FLAG
#endif /* PCAP_ERROR_TSTAMP_TYPE_NOTSUP */
#ifdef HAVE_PCAP_FINDALLDEVS
#ifndef HAVE_PCAP_IF_T
#undef HAVE_PCAP_FINDALLDEVS
#endif
#endif
#ifdef HAVE_PCAP_FINDALLDEVS
#define D_FLAG "D"
#else
#define D_FLAG
#endif
#ifdef HAVE_PCAP_DUMP_FLUSH
#define U_FLAG "U"
#else
#define U_FLAG
#endif
#ifndef WIN32
/* Drop root privileges and chroot if necessary */
static void
droproot(const char *username, const char *chroot_dir)
{
struct passwd *pw = NULL;
if (chroot_dir && !username) {
fprintf(stderr, "tcpdump: Chroot without dropping root is insecure\n");
exit(1);
}
pw = getpwnam(username);
if (pw) {
if (chroot_dir) {
if (chroot(chroot_dir) != 0 || chdir ("/") != 0) {
fprintf(stderr, "tcpdump: Couldn't chroot/chdir to '%.64s': %s\n",
chroot_dir, pcap_strerror(errno));
exit(1);
}
}
#ifdef HAVE_CAP_NG_H
int ret = capng_change_id(pw->pw_uid, pw->pw_gid, CAPNG_NO_FLAG);
if (ret < 0) {
printf("error : ret %d\n", ret);
}
/* We don't need CAP_SETUID and CAP_SETGID */
capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_SETUID);
capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_SETUID);
capng_update(CAPNG_DROP, CAPNG_PERMITTED, CAP_SETUID);
capng_update(CAPNG_DROP, CAPNG_PERMITTED, CAP_SETUID);
capng_apply(CAPNG_SELECT_BOTH);
#else
if (initgroups(pw->pw_name, pw->pw_gid) != 0 ||
setgid(pw->pw_gid) != 0 || setuid(pw->pw_uid) != 0) {
fprintf(stderr, "tcpdump: Couldn't change to '%.32s' uid=%lu gid=%lu: %s\n",
username,
(unsigned long)pw->pw_uid,
(unsigned long)pw->pw_gid,
pcap_strerror(errno));
exit(1);
}
#endif /* HAVE_CAP_NG_H */
}
else {
fprintf(stderr, "tcpdump: Couldn't find user '%.32s'\n",
username);
exit(1);
}
}
#endif /* WIN32 */
static int
getWflagChars(int x)
{
int c = 0;
x -= 1;
while (x > 0) {
c += 1;
x /= 10;
}
return c;
}
static void
MakeFilename(char *buffer, char *orig_name, int cnt, int max_chars)
{
char *filename = malloc(PATH_MAX + 1);
if (filename == NULL)
error("Makefilename: malloc");
/* Process with strftime if Gflag is set. */
if (Gflag != 0) {
struct tm *local_tm;
/* Convert Gflag_time to a usable format */
if ((local_tm = localtime(&Gflag_time)) == NULL) {
error("MakeTimedFilename: localtime");
}
/* There's no good way to detect an error in strftime since a return
* value of 0 isn't necessarily failure.
*/
strftime(filename, PATH_MAX, orig_name, local_tm);
} else {
strncpy(filename, orig_name, PATH_MAX);
}
if (cnt == 0 && max_chars == 0)
strncpy(buffer, filename, PATH_MAX + 1);
else
if (snprintf(buffer, PATH_MAX + 1, "%s%0*d", filename, max_chars, cnt) > PATH_MAX)
/* Report an error if the filename is too large */
error("too many output files or filename is too long (> %d)", PATH_MAX);
free(filename);
}
static int tcpdump_printf(netdissect_options *ndo _U_,
const char *fmt, ...)
{
va_list args;
int ret;
va_start(args, fmt);
ret=vfprintf(stdout, fmt, args);
va_end(args);
return ret;
}
static struct print_info
get_print_info(int type)
{
struct print_info printinfo;
printinfo.ndo_type = 1;
printinfo.ndo = gndo;
printinfo.p.ndo_printer = lookup_ndo_printer(type);
if (printinfo.p.ndo_printer == NULL) {
printinfo.p.printer = lookup_printer(type);
printinfo.ndo_type = 0;
if (printinfo.p.printer == NULL) {
gndo->ndo_dltname = pcap_datalink_val_to_name(type);
if (gndo->ndo_dltname != NULL)
error("packet printing is not supported for link type %s: use -w",
gndo->ndo_dltname);
else
error("packet printing is not supported for link type %d: use -w", type);
}
}
return (printinfo);
}
static char *
get_next_file(FILE *VFile, char *ptr)
{
char *ret;
ret = fgets(ptr, PATH_MAX, VFile);
if (!ret)
return NULL;
if (ptr[strlen(ptr) - 1] == '\n')
ptr[strlen(ptr) - 1] = '\0';
return ret;
}
#ifdef HAVE_LIBCAPSICUM
static cap_channel_t *
capdns_setup(void)
{
cap_channel_t *capcas, *capdnsloc;
const char *types[1];
int families[2];
capcas = cap_init();
if (capcas == NULL) {
warning("unable to contact casperd");
return (NULL);
}
capdnsloc = cap_service_open(capcas, "system.dns");
/* Casper capability no longer needed. */
cap_close(capcas);
if (capdnsloc == NULL)
error("unable to open system.dns service");
/* Limit system.dns to reverse DNS lookups. */
types[0] = "ADDR";
if (cap_dns_type_limit(capdnsloc, types, 1) < 0)
error("unable to limit access to system.dns service");
families[0] = AF_INET;
families[1] = AF_INET6;
if (cap_dns_family_limit(capdnsloc, families, 2) < 0)
error("unable to limit access to system.dns service");
return (capdnsloc);
}
#endif /* HAVE_LIBCAPSICUM */
int
main(int argc, char **argv)
{
register int cnt, op, i;
bpf_u_int32 localnet, netmask;
register char *cp, *infile, *cmdbuf, *device, *RFileName, *VFileName, *WFileName;
pcap_handler callback;
int type;
int dlt;
int new_dlt;
const char *dlt_name;
struct bpf_program fcode;
#ifndef WIN32
RETSIGTYPE (*oldhandler)(int);
#endif
struct print_info printinfo;
struct dump_info dumpinfo;
u_char *pcap_userdata;
char ebuf[PCAP_ERRBUF_SIZE];
char VFileLine[PATH_MAX + 1];
char *username = NULL;
char *chroot_dir = NULL;
char *ret = NULL;
char *end;
#ifdef HAVE_PCAP_FINDALLDEVS
pcap_if_t *devpointer;
int devnum;
#endif
int status;
FILE *VFile;
#ifdef __FreeBSD__
cap_rights_t rights;
int cansandbox;
#endif /* __FreeBSD__ */
#ifdef WIN32
if(wsockinit() != 0) return 1;
#endif /* WIN32 */
jflag=-1; /* not set */
gndo->ndo_Oflag=1;
gndo->ndo_Rflag=1;
gndo->ndo_dlt=-1;
gndo->ndo_default_print=ndo_default_print;
gndo->ndo_printf=tcpdump_printf;
gndo->ndo_error=ndo_error;
gndo->ndo_warning=ndo_warning;
gndo->ndo_snaplen = DEFAULT_SNAPLEN;
cnt = -1;
device = NULL;
infile = NULL;
RFileName = NULL;
VFileName = NULL;
VFile = NULL;
WFileName = NULL;
dlt = -1;
if ((cp = strrchr(argv[0], '/')) != NULL)
program_name = cp + 1;
else
program_name = argv[0];
if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
error("%s", ebuf);
#ifdef LIBSMI
smiInit("tcpdump");
#endif
while (
(op = getopt(argc, argv, "aAb" B_FLAG "c:C:d" D_FLAG "eE:fF:G:hHi:" I_FLAG j_FLAG J_FLAG "KlLm:M:nNOpqr:Rs:StT:u" U_FLAG "V:vw:W:xXy:Yz:Z:")) != -1)
switch (op) {
case 'a':
/* compatibility for old -a */
break;
case 'A':
++Aflag;
break;
case 'b':
++bflag;
break;
#if defined(HAVE_PCAP_CREATE) || defined(WIN32)
case 'B':
Bflag = atoi(optarg)*1024;
if (Bflag <= 0)
error("invalid packet buffer size %s", optarg);
break;
#endif /* defined(HAVE_PCAP_CREATE) || defined(WIN32) */
case 'c':
cnt = atoi(optarg);
if (cnt <= 0)
error("invalid packet count %s", optarg);
break;
case 'C':
Cflag = atoi(optarg) * 1000000;
if (Cflag < 0)
error("invalid file size %s", optarg);
break;
case 'd':
++dflag;
break;
#ifdef HAVE_PCAP_FINDALLDEVS
case 'D':
if (pcap_findalldevs(&devpointer, ebuf) < 0)
error("%s", ebuf);
else {
for (i = 0; devpointer != 0; i++) {
printf("%d.%s", i+1, devpointer->name);
if (devpointer->description != NULL)
printf(" (%s)", devpointer->description);
printf("\n");
devpointer = devpointer->next;
}
}
return 0;
#endif /* HAVE_PCAP_FINDALLDEVS */
case 'L':
Lflag++;
break;
case 'e':
++eflag;
break;
case 'E':
#ifndef HAVE_LIBCRYPTO
warning("crypto code not compiled in");
#endif
gndo->ndo_espsecret = optarg;
break;
case 'f':
++fflag;
break;
case 'F':
infile = optarg;
break;
case 'G':
Gflag = atoi(optarg);
if (Gflag < 0)
error("invalid number of seconds %s", optarg);
/* We will create one file initially. */
Gflag_count = 0;
/* Grab the current time for rotation use. */
if ((Gflag_time = time(NULL)) == (time_t)-1) {
error("main: can't get current time: %s",
pcap_strerror(errno));
}
break;
case 'h':
usage();
break;
case 'H':
++Hflag;
break;
case 'i':
if (optarg[0] == '0' && optarg[1] == 0)
error("Invalid adapter index");
#ifdef HAVE_PCAP_FINDALLDEVS
/*
* If the argument is a number, treat it as
* an index into the list of adapters, as
* printed by "tcpdump -D".
*
* This should be OK on UNIX systems, as interfaces
* shouldn't have names that begin with digits.
* It can be useful on Windows, where more than
* one interface can have the same name.
*/
devnum = strtol(optarg, &end, 10);
if (optarg != end && *end == '\0') {
if (devnum < 0)
error("Invalid adapter index");
if (pcap_findalldevs(&devpointer, ebuf) < 0)
error("%s", ebuf);
else {
/*
* Look for the devnum-th entry
* in the list of devices
* (1-based).
*/
for (i = 0;
i < devnum-1 && devpointer != NULL;
i++, devpointer = devpointer->next)
;
if (devpointer == NULL)
error("Invalid adapter index");
}
device = devpointer->name;
break;
}
#endif /* HAVE_PCAP_FINDALLDEVS */
device = optarg;
break;
#ifdef HAVE_PCAP_CREATE
case 'I':
++Iflag;
break;
#endif /* HAVE_PCAP_CREATE */
#ifdef HAVE_PCAP_SET_TSTAMP_TYPE
case 'j':
jflag = pcap_tstamp_type_name_to_val(optarg);
if (jflag < 0)
error("invalid time stamp type %s", optarg);
break;
case 'J':
Jflag++;
break;
#endif
case 'l':
#ifdef WIN32
/*
* _IOLBF is the same as _IOFBF in Microsoft's C
* libraries; the only alternative they offer
* is _IONBF.
*
* XXX - this should really be checking for MSVC++,
* not WIN32, if, for example, MinGW has its own
* C library that is more UNIX-compatible.
*/
setvbuf(stdout, NULL, _IONBF, 0);
#else /* WIN32 */
#ifdef HAVE_SETLINEBUF
setlinebuf(stdout);
#else
setvbuf(stdout, NULL, _IOLBF, 0);
#endif
#endif /* WIN32 */
break;
case 'K':
++Kflag;
break;
case 'm':
#ifdef LIBSMI
if (smiLoadModule(optarg) == 0) {
error("could not load MIB module %s", optarg);
}
sflag = 1;
#else
(void)fprintf(stderr, "%s: ignoring option `-m %s' ",
program_name, optarg);
(void)fprintf(stderr, "(no libsmi support)\n");
#endif
break;
case 'M':
/* TCP-MD5 shared secret */
#ifndef HAVE_LIBCRYPTO
warning("crypto code not compiled in");
#endif
sigsecret = optarg;
break;
case 'n':
++nflag;
break;
case 'N':
++Nflag;
break;
case 'O':
Oflag = 0;
break;
case 'p':
++pflag;
break;
case 'q':
++qflag;
++suppress_default_print;
break;
case 'r':
RFileName = optarg;
break;
case 'R':
Rflag = 0;
break;
case 's':
snaplen = strtol(optarg, &end, 0);
if (optarg == end || *end != '\0'
|| snaplen < 0 || snaplen > MAXIMUM_SNAPLEN)
error("invalid snaplen %s", optarg);
else if (snaplen == 0)
snaplen = MAXIMUM_SNAPLEN;
break;
case 'S':
++Sflag;
break;
case 't':
++tflag;
break;
case 'T':
if (strcasecmp(optarg, "vat") == 0)
packettype = PT_VAT;
else if (strcasecmp(optarg, "wb") == 0)
packettype = PT_WB;
else if (strcasecmp(optarg, "rpc") == 0)
packettype = PT_RPC;
else if (strcasecmp(optarg, "rtp") == 0)
packettype = PT_RTP;
else if (strcasecmp(optarg, "rtcp") == 0)
packettype = PT_RTCP;
else if (strcasecmp(optarg, "snmp") == 0)
packettype = PT_SNMP;
else if (strcasecmp(optarg, "cnfp") == 0)
packettype = PT_CNFP;
else if (strcasecmp(optarg, "tftp") == 0)
packettype = PT_TFTP;
else if (strcasecmp(optarg, "aodv") == 0)
packettype = PT_AODV;
else if (strcasecmp(optarg, "carp") == 0)
packettype = PT_CARP;
else if (strcasecmp(optarg, "radius") == 0)
packettype = PT_RADIUS;
else if (strcasecmp(optarg, "zmtp1") == 0)
packettype = PT_ZMTP1;
else if (strcasecmp(optarg, "vxlan") == 0)
packettype = PT_VXLAN;
else
error("unknown packet type `%s'", optarg);
break;
case 'u':
++uflag;
break;
#ifdef HAVE_PCAP_DUMP_FLUSH
case 'U':
++Uflag;
break;
#endif
case 'v':
++vflag;
break;
case 'V':
VFileName = optarg;
break;
case 'w':
WFileName = optarg;
break;
case 'W':
Wflag = atoi(optarg);
if (Wflag < 0)
error("invalid number of output files %s", optarg);
WflagChars = getWflagChars(Wflag);
break;
case 'x':
++xflag;
++suppress_default_print;
break;
case 'X':
++Xflag;
++suppress_default_print;
break;
case 'y':
gndo->ndo_dltname = optarg;
gndo->ndo_dlt =
pcap_datalink_name_to_val(gndo->ndo_dltname);
if (gndo->ndo_dlt < 0)
error("invalid data link type %s", gndo->ndo_dltname);
break;
#if defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG)
case 'Y':
{
/* Undocumented flag */
#ifdef HAVE_PCAP_DEBUG
extern int pcap_debug;
pcap_debug = 1;
#else
extern int yydebug;
yydebug = 1;
#endif
}
break;
#endif
case 'z':
if (optarg) {
zflag = strdup(optarg);
} else {
usage();
/* NOTREACHED */
}
break;
case 'Z':
if (optarg) {
username = strdup(optarg);
}
else {
usage();
/* NOTREACHED */
}
break;
default:
usage();
/* NOTREACHED */
}
switch (tflag) {
case 0: /* Default */
case 4: /* Default + Date*/
thiszone = gmt2local(0);
break;
case 1: /* No time stamp */
case 2: /* Unix timeval style */
case 3: /* Microseconds since previous packet */
case 5: /* Microseconds since first packet */
break;
default: /* Not supported */
error("only -t, -tt, -ttt, -tttt and -ttttt are supported");
break;
}
if (fflag != 0 && (VFileName != NULL || RFileName != NULL))
error("-f can not be used with -V or -r");
if (VFileName != NULL && RFileName != NULL)
error("-V and -r are mutually exclusive.");
#ifdef WITH_CHROOT
/* if run as root, prepare for chrooting */
if (getuid() == 0 || geteuid() == 0) {
/* future extensibility for cmd-line arguments */
if (!chroot_dir)
chroot_dir = WITH_CHROOT;
}
#endif
#ifdef WITH_USER
/* if run as root, prepare for dropping root privileges */
if (getuid() == 0 || geteuid() == 0) {
/* Run with '-Z root' to restore old behaviour */
if (!username)
username = WITH_USER;
}
#endif
if (RFileName != NULL || VFileName != NULL) {
/*
* If RFileName is non-null, it's the pathname of a
* savefile to read. If VFileName is non-null, it's
* the pathname of a file containing a list of pathnames
* (one per line) of savefiles to read.
*
* In either case, we're reading a savefile, not doing
* a live capture.
*/
#ifndef WIN32
/*
* We don't need network access, so relinquish any set-UID
* or set-GID privileges we have (if any).
*
* We do *not* want set-UID privileges when opening a
* trace file, as that might let the user read other
* people's trace files (especially if we're set-UID
* root).
*/
if (setgid(getgid()) != 0 || setuid(getuid()) != 0 )
fprintf(stderr, "Warning: setgid/setuid failed !\n");
#endif /* WIN32 */
if (VFileName != NULL) {
if (VFileName[0] == '-' && VFileName[1] == '\0')
VFile = stdin;
else
VFile = fopen(VFileName, "r");
if (VFile == NULL)
error("Unable to open file: %s\n", strerror(errno));
ret = get_next_file(VFile, VFileLine);
if (!ret)
error("Nothing in %s\n", VFileName);
RFileName = VFileLine;
}
pd = pcap_open_offline(RFileName, ebuf);
if (pd == NULL)
error("%s", ebuf);
#ifdef __FreeBSD__
cap_rights_init(&rights, CAP_READ);
if (cap_rights_limit(fileno(pcap_file(pd)), &rights) < 0 &&
errno != ENOSYS) {
error("unable to limit pcap descriptor");
}
#endif
dlt = pcap_datalink(pd);
dlt_name = pcap_datalink_val_to_name(dlt);
if (dlt_name == NULL) {
fprintf(stderr, "reading from file %s, link-type %u\n",
RFileName, dlt);
} else {
fprintf(stderr,
"reading from file %s, link-type %s (%s)\n",
RFileName, dlt_name,
pcap_datalink_val_to_description(dlt));
}
localnet = 0;
netmask = 0;
} else {
/*
* We're doing a live capture.
*/
if (device == NULL) {
device = pcap_lookupdev(ebuf);
if (device == NULL)
error("%s", ebuf);
}
#ifdef WIN32
/*
* Print a message to the standard error on Windows.
* XXX - why do it here, with a different message?
*/
if(strlen(device) == 1) //we assume that an ASCII string is always longer than 1 char
{ //a Unicode string has a \0 as second byte (so strlen() is 1)
fprintf(stderr, "%s: listening on %ws\n", program_name, device);
}
else
{
fprintf(stderr, "%s: listening on %s\n", program_name, device);
}
fflush(stderr);
#endif /* WIN32 */
#ifdef HAVE_PCAP_CREATE
pd = pcap_create(device, ebuf);
if (pd == NULL)
error("%s", ebuf);
#ifdef HAVE_PCAP_SET_TSTAMP_TYPE
if (Jflag)
show_tstamp_types_and_exit(device, pd);
#endif
/*
* Is this an interface that supports monitor mode?
*/
if (pcap_can_set_rfmon(pd) == 1)
supports_monitor_mode = 1;
else
supports_monitor_mode = 0;
status = pcap_set_snaplen(pd, snaplen);
if (status != 0)
error("%s: Can't set snapshot length: %s",
device, pcap_statustostr(status));
status = pcap_set_promisc(pd, !pflag);
if (status != 0)
error("%s: Can't set promiscuous mode: %s",
device, pcap_statustostr(status));
if (Iflag) {
status = pcap_set_rfmon(pd, 1);
if (status != 0)
error("%s: Can't set monitor mode: %s",
device, pcap_statustostr(status));
}
status = pcap_set_timeout(pd, 1000);
if (status != 0)
error("%s: pcap_set_timeout failed: %s",
device, pcap_statustostr(status));
if (Bflag != 0) {
status = pcap_set_buffer_size(pd, Bflag);
if (status != 0)
error("%s: Can't set buffer size: %s",
device, pcap_statustostr(status));
}
#ifdef HAVE_PCAP_SET_TSTAMP_TYPE
if (jflag != -1) {
status = pcap_set_tstamp_type(pd, jflag);
if (status < 0)
error("%s: Can't set time stamp type: %s",
device, pcap_statustostr(status));
}
#endif
status = pcap_activate(pd);
if (status < 0) {
/*
* pcap_activate() failed.
*/
cp = pcap_geterr(pd);
if (status == PCAP_ERROR)
error("%s", cp);
else if ((status == PCAP_ERROR_NO_SUCH_DEVICE ||
status == PCAP_ERROR_PERM_DENIED) &&
*cp != '\0')
error("%s: %s\n(%s)", device,
pcap_statustostr(status), cp);
#ifdef __FreeBSD__
else if (status == PCAP_ERROR_RFMON_NOTSUP &&
strncmp(device, "wlan", 4) == 0) {
char parent[8], newdev[8];
char sysctl[32];
size_t s = sizeof(parent);
snprintf(sysctl, sizeof(sysctl),
"net.wlan.%d.%%parent", atoi(device + 4));
sysctlbyname(sysctl, parent, &s, NULL, 0);
strlcpy(newdev, device, sizeof(newdev));
/* Suggest a new wlan device. */
newdev[strlen(newdev)-1]++;
error("%s is not a monitor mode VAP\n"
"To create a new monitor mode VAP use:\n"
" ifconfig %s create wlandev %s wlanmode "
"monitor\nand use %s as the tcpdump "
"interface", device, newdev, parent,
newdev);
}
#endif
else
error("%s: %s", device,
pcap_statustostr(status));
} else if (status > 0) {
/*
* pcap_activate() succeeded, but it's warning us
* of a problem it had.
*/
cp = pcap_geterr(pd);
if (status == PCAP_WARNING)
warning("%s", cp);
else if (status == PCAP_WARNING_PROMISC_NOTSUP &&
*cp != '\0')
warning("%s: %s\n(%s)", device,
pcap_statustostr(status), cp);
else
warning("%s: %s", device,
pcap_statustostr(status));
}
#else
*ebuf = '\0';
pd = pcap_open_live(device, snaplen, !pflag, 1000, ebuf);
if (pd == NULL)
error("%s", ebuf);
else if (*ebuf)
warning("%s", ebuf);
#endif /* HAVE_PCAP_CREATE */
/*
* Let user own process after socket has been opened.
*/
#ifndef WIN32
if (setgid(getgid()) != 0 || setuid(getuid()) != 0)
fprintf(stderr, "Warning: setgid/setuid failed !\n");
#endif /* WIN32 */
#if !defined(HAVE_PCAP_CREATE) && defined(WIN32)
if(Bflag != 0)
if(pcap_setbuff(pd, Bflag)==-1){
error("%s", pcap_geterr(pd));
}
#endif /* !defined(HAVE_PCAP_CREATE) && defined(WIN32) */
if (Lflag)
show_dlts_and_exit(device, pd);
if (gndo->ndo_dlt >= 0) {
#ifdef HAVE_PCAP_SET_DATALINK
if (pcap_set_datalink(pd, gndo->ndo_dlt) < 0)
error("%s", pcap_geterr(pd));
#else
/*
* We don't actually support changing the
* data link type, so we only let them
* set it to what it already is.
*/
if (gndo->ndo_dlt != pcap_datalink(pd)) {
error("%s is not one of the DLTs supported by this device\n",
gndo->ndo_dltname);
}
#endif
(void)fprintf(stderr, "%s: data link type %s\n",
program_name, gndo->ndo_dltname);
(void)fflush(stderr);
}
i = pcap_snapshot(pd);
if (snaplen < i) {
warning("snaplen raised from %d to %d", snaplen, i);
snaplen = i;
}
if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
localnet = 0;
netmask = 0;
warning("%s", ebuf);
}
}
if (infile)
cmdbuf = read_infile(infile);
else
cmdbuf = copy_argv(&argv[optind]);
if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
error("%s", pcap_geterr(pd));
if (dflag) {
bpf_dump(&fcode, dflag);
pcap_close(pd);
free(cmdbuf);
exit(0);
}
#ifdef HAVE_LIBCAPSICUM
if (!nflag)
capdns = capdns_setup();
#endif /* HAVE_LIBCAPSICUM */
init_addrtoname(localnet, netmask);
init_checksum();
#ifndef WIN32
(void)setsignal(SIGPIPE, cleanup);
(void)setsignal(SIGTERM, cleanup);
(void)setsignal(SIGINT, cleanup);
#endif /* WIN32 */
#if defined(HAVE_FORK) || defined(HAVE_VFORK)
(void)setsignal(SIGCHLD, child_cleanup);
#endif
/* Cooperate with nohup(1) */
#ifndef WIN32
if ((oldhandler = setsignal(SIGHUP, cleanup)) != SIG_DFL)
(void)setsignal(SIGHUP, oldhandler);
#endif /* WIN32 */
#ifndef WIN32
/*
* If a user name was specified with "-Z", attempt to switch to
* that user's UID. This would probably be used with sudo,
* to allow tcpdump to be run in a special restricted
* account (if you just want to allow users to open capture
* devices, and can't just give users that permission,
* you'd make tcpdump set-UID or set-GID).
*
* Tcpdump doesn't necessarily write only to one savefile;
* the general only way to allow a -Z instance to write to
* savefiles as the user under whose UID it's run, rather
* than as the user specified with -Z, would thus be to switch
* to the original user ID before opening a capture file and
* then switch back to the -Z user ID after opening the savefile.
* Switching to the -Z user ID only after opening the first
* savefile doesn't handle the general case.
*/
#ifdef HAVE_CAP_NG_H
/* We are running as root and we will be writing to savefile */
if ((getuid() == 0 || geteuid() == 0) && WFileName) {
if (username) {
/* Drop all capabilities from effective set */
capng_clear(CAPNG_EFFECTIVE);
/* Add capabilities we will need*/
capng_update(CAPNG_ADD, CAPNG_PERMITTED, CAP_SETUID);
capng_update(CAPNG_ADD, CAPNG_PERMITTED, CAP_SETGID);
capng_update(CAPNG_ADD, CAPNG_PERMITTED, CAP_DAC_OVERRIDE);
capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_SETUID);
capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_SETGID);
capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
capng_apply(CAPNG_SELECT_BOTH);
}
}
#endif /* HAVE_CAP_NG_H */
if (getuid() == 0 || geteuid() == 0) {
if (username || chroot_dir)
droproot(username, chroot_dir);
}
#endif /* WIN32 */
if (pcap_setfilter(pd, &fcode) < 0)
error("%s", pcap_geterr(pd));
#ifdef __FreeBSD__
if (RFileName == NULL && VFileName == NULL) {
static const unsigned long cmds[] = { BIOCGSTATS };
cap_rights_init(&rights, CAP_IOCTL, CAP_READ);
if (cap_rights_limit(pcap_fileno(pd), &rights) < 0 &&
errno != ENOSYS) {
error("unable to limit pcap descriptor");
}
if (cap_ioctls_limit(pcap_fileno(pd), cmds,
sizeof(cmds) / sizeof(cmds[0])) < 0 && errno != ENOSYS) {
error("unable to limit ioctls on pcap descriptor");
}
}
#endif
if (WFileName) {
pcap_dumper_t *p;
/* Do not exceed the default PATH_MAX for files. */
dumpinfo.CurrentFileName = (char *)malloc(PATH_MAX + 1);
if (dumpinfo.CurrentFileName == NULL)
error("malloc of dumpinfo.CurrentFileName");
/* We do not need numbering for dumpfiles if Cflag isn't set. */
if (Cflag != 0)
MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, WflagChars);
else
MakeFilename(dumpinfo.CurrentFileName, WFileName, 0, 0);
p = pcap_dump_open(pd, dumpinfo.CurrentFileName);
#ifdef HAVE_CAP_NG_H
/* Give up capabilities, clear Effective set */
capng_clear(CAPNG_EFFECTIVE);
#endif
if (p == NULL)
error("%s", pcap_geterr(pd));
#ifdef __FreeBSD__
cap_rights_init(&rights, CAP_SEEK, CAP_WRITE);
if (cap_rights_limit(fileno(pcap_dump_file(p)), &rights) < 0 &&
errno != ENOSYS) {
error("unable to limit dump descriptor");
}
#endif
if (Cflag != 0 || Gflag != 0) {
#ifdef __FreeBSD__
dumpinfo.WFileName = strdup(basename(WFileName));
dumpinfo.dirfd = open(dirname(WFileName),
O_DIRECTORY | O_RDONLY);
if (dumpinfo.dirfd < 0) {
error("unable to open directory %s",
dirname(WFileName));
}
cap_rights_init(&rights, CAP_CREATE, CAP_FCNTL,
CAP_FTRUNCATE, CAP_LOOKUP, CAP_SEEK, CAP_WRITE);
if (cap_rights_limit(dumpinfo.dirfd, &rights) < 0 &&
errno != ENOSYS) {
error("unable to limit directory rights");
}
#else /* !__FreeBSD__ */
dumpinfo.WFileName = WFileName;
#endif
callback = dump_packet_and_trunc;
dumpinfo.pd = pd;
dumpinfo.p = p;
pcap_userdata = (u_char *)&dumpinfo;
} else {
callback = dump_packet;
pcap_userdata = (u_char *)p;
}
#ifdef HAVE_PCAP_DUMP_FLUSH
if (Uflag)
pcap_dump_flush(p);
#endif
} else {
type = pcap_datalink(pd);
printinfo = get_print_info(type);
callback = print_packet;
pcap_userdata = (u_char *)&printinfo;
}
#ifdef SIGNAL_REQ_INFO
/*
* We can't get statistics when reading from a file rather
* than capturing from a device.
*/
if (RFileName == NULL)
(void)setsignal(SIGNAL_REQ_INFO, requestinfo);
#endif
if (vflag > 0 && WFileName) {
/*
* When capturing to a file, "-v" means tcpdump should,
* every 10 secodns, "v"erbosely report the number of
* packets captured.
*/
#ifdef USE_WIN32_MM_TIMER
/* call verbose_stats_dump() each 1000 +/-100msec */
timer_id = timeSetEvent(1000, 100, verbose_stats_dump, 0, TIME_PERIODIC);
setvbuf(stderr, NULL, _IONBF, 0);
#elif defined(HAVE_ALARM)
(void)setsignal(SIGALRM, verbose_stats_dump);
alarm(1);
#endif
}
#ifndef WIN32
if (RFileName == NULL) {
/*
* Live capture (if -V was specified, we set RFileName
* to a file from the -V file). Print a message to
* the standard error on UN*X.
*/
if (!vflag && !WFileName) {
(void)fprintf(stderr,
"%s: verbose output suppressed, use -v or -vv for full protocol decode\n",
program_name);
} else
(void)fprintf(stderr, "%s: ", program_name);
dlt = pcap_datalink(pd);
dlt_name = pcap_datalink_val_to_name(dlt);
if (dlt_name == NULL) {
(void)fprintf(stderr, "listening on %s, link-type %u, capture size %u bytes\n",
device, dlt, snaplen);
} else {
(void)fprintf(stderr, "listening on %s, link-type %s (%s), capture size %u bytes\n",
device, dlt_name,
pcap_datalink_val_to_description(dlt), snaplen);
}
(void)fflush(stderr);
}
#endif /* WIN32 */
#ifdef __FreeBSD__
cansandbox = (VFileName == NULL && zflag == NULL);
#ifdef HAVE_LIBCAPSICUM
cansandbox = (cansandbox && (nflag || capdns != NULL));
#else
cansandbox = (cansandbox && nflag);
#endif
if (cansandbox && cap_enter() < 0 && errno != ENOSYS)
error("unable to enter the capability mode");
if (cap_sandboxed())
fprintf(stderr, "capability mode sandbox enabled\n");
#endif /* __FreeBSD__ */
do {
status = pcap_loop(pd, cnt, callback, pcap_userdata);
if (WFileName == NULL) {
/*
* We're printing packets. Flush the printed output,
* so it doesn't get intermingled with error output.
*/
if (status == -2) {
/*
* We got interrupted, so perhaps we didn't
* manage to finish a line we were printing.
* Print an extra newline, just in case.
*/
putchar('\n');
}
(void)fflush(stdout);
}
if (status == -1) {
/*
* Error. Report it.
*/
(void)fprintf(stderr, "%s: pcap_loop: %s\n",
program_name, pcap_geterr(pd));
}
if (RFileName == NULL) {
/*
* We're doing a live capture. Report the capture
* statistics.
*/
info(1);
}
pcap_close(pd);
if (VFileName != NULL) {
ret = get_next_file(VFile, VFileLine);
if (ret) {
RFileName = VFileLine;
pd = pcap_open_offline(RFileName, ebuf);
if (pd == NULL)
error("%s", ebuf);
#ifdef __FreeBSD__
cap_rights_init(&rights, CAP_READ);
if (cap_rights_limit(fileno(pcap_file(pd)),
&rights) < 0 && errno != ENOSYS) {
error("unable to limit pcap descriptor");
}
#endif
new_dlt = pcap_datalink(pd);
if (WFileName && new_dlt != dlt)
error("%s: new dlt does not match original", RFileName);
printinfo = get_print_info(new_dlt);
dlt_name = pcap_datalink_val_to_name(new_dlt);
if (dlt_name == NULL) {
fprintf(stderr, "reading from file %s, link-type %u\n",
RFileName, new_dlt);
} else {
fprintf(stderr,
"reading from file %s, link-type %s (%s)\n",
RFileName, dlt_name,
pcap_datalink_val_to_description(new_dlt));
}
if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
error("%s", pcap_geterr(pd));
if (pcap_setfilter(pd, &fcode) < 0)
error("%s", pcap_geterr(pd));
}
}
}
while (ret != NULL);
free(cmdbuf);
exit(status == -1 ? 1 : 0);
}
/* make a clean exit on interrupts */
static RETSIGTYPE
cleanup(int signo _U_)
{
#ifdef USE_WIN32_MM_TIMER
if (timer_id)
timeKillEvent(timer_id);
timer_id = 0;
#elif defined(HAVE_ALARM)
alarm(0);
#endif
#ifdef HAVE_PCAP_BREAKLOOP
/*
* We have "pcap_breakloop()"; use it, so that we do as little
* as possible in the signal handler (it's probably not safe
* to do anything with standard I/O streams in a signal handler -
* the ANSI C standard doesn't say it is).
*/
pcap_breakloop(pd);
#else
/*
* We don't have "pcap_breakloop()"; this isn't safe, but
* it's the best we can do. Print the summary if we're
* not reading from a savefile - i.e., if we're doing a
* live capture - and exit.
*/
if (pd != NULL && pcap_file(pd) == NULL) {
/*
* We got interrupted, so perhaps we didn't
* manage to finish a line we were printing.
* Print an extra newline, just in case.
*/
putchar('\n');
(void)fflush(stdout);
info(1);
}
exit(0);
#endif
}
/*
On windows, we do not use a fork, so we do not care less about
waiting a child processes to die
*/
#if defined(HAVE_FORK) || defined(HAVE_VFORK)
static RETSIGTYPE
child_cleanup(int signo _U_)
{
wait(NULL);
}
#endif /* HAVE_FORK && HAVE_VFORK */
static void
info(register int verbose)
{
struct pcap_stat stat;
/*
* Older versions of libpcap didn't set ps_ifdrop on some
* platforms; initialize it to 0 to handle that.
*/
stat.ps_ifdrop = 0;
if (pcap_stats(pd, &stat) < 0) {
(void)fprintf(stderr, "pcap_stats: %s\n", pcap_geterr(pd));
infoprint = 0;
return;
}
if (!verbose)
fprintf(stderr, "%s: ", program_name);
(void)fprintf(stderr, "%u packet%s captured", packets_captured,
PLURAL_SUFFIX(packets_captured));
if (!verbose)
fputs(", ", stderr);
else
putc('\n', stderr);
(void)fprintf(stderr, "%u packet%s received by filter", stat.ps_recv,
PLURAL_SUFFIX(stat.ps_recv));
if (!verbose)
fputs(", ", stderr);
else
putc('\n', stderr);
(void)fprintf(stderr, "%u packet%s dropped by kernel", stat.ps_drop,
PLURAL_SUFFIX(stat.ps_drop));
if (stat.ps_ifdrop != 0) {
if (!verbose)
fputs(", ", stderr);
else
putc('\n', stderr);
(void)fprintf(stderr, "%u packet%s dropped by interface\n",
stat.ps_ifdrop, PLURAL_SUFFIX(stat.ps_ifdrop));
} else
putc('\n', stderr);
infoprint = 0;
}
#if defined(HAVE_FORK) || defined(HAVE_VFORK)
static void
compress_savefile(const char *filename)
{
# ifdef HAVE_FORK
if (fork())
# else
if (vfork())
# endif
return;
/*
* Set to lowest priority so that this doesn't disturb the capture
*/
#ifdef NZERO
setpriority(PRIO_PROCESS, 0, NZERO - 1);
#else
setpriority(PRIO_PROCESS, 0, 19);
#endif
if (execlp(zflag, zflag, filename, (char *)NULL) == -1)
fprintf(stderr,
"compress_savefile:execlp(%s, %s): %s\n",
zflag,
filename,
strerror(errno));
# ifdef HAVE_FORK
exit(1);
# else
_exit(1);
# endif
}
#else /* HAVE_FORK && HAVE_VFORK */
static void
compress_savefile(const char *filename)
{
fprintf(stderr,
"compress_savefile failed. Functionality not implemented under your system\n");
}
#endif /* HAVE_FORK && HAVE_VFORK */
static void
dump_packet_and_trunc(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
{
struct dump_info *dump_info;
#ifdef __FreeBSD__
cap_rights_t rights;
#endif
++packets_captured;
++infodelay;
dump_info = (struct dump_info *)user;
/*
* XXX - this won't force the file to rotate on the specified time
* boundary, but it will rotate on the first packet received after the
* specified Gflag number of seconds. Note: if a Gflag time boundary
* and a Cflag size boundary coincide, the time rotation will occur
* first thereby cancelling the Cflag boundary (since the file should
* be 0).
*/
if (Gflag != 0) {
/* Check if it is time to rotate */
time_t t;
/* Get the current time */
if ((t = time(NULL)) == (time_t)-1) {
error("dump_and_trunc_packet: can't get current_time: %s",
pcap_strerror(errno));
}
/* If the time is greater than the specified window, rotate */
if (t - Gflag_time >= Gflag) {
#ifdef __FreeBSD__
FILE *fp;
int fd;
#endif
/* Update the Gflag_time */
Gflag_time = t;
/* Update Gflag_count */
Gflag_count++;
/*
* Close the current file and open a new one.
*/
pcap_dump_close(dump_info->p);
/*
* Compress the file we just closed, if the user asked for it
*/
if (zflag != NULL)
compress_savefile(dump_info->CurrentFileName);
/*
* Check to see if we've exceeded the Wflag (when
* not using Cflag).
*/
if (Cflag == 0 && Wflag > 0 && Gflag_count >= Wflag) {
(void)fprintf(stderr, "Maximum file limit reached: %d\n",
Wflag);
exit(0);
/* NOTREACHED */
}
if (dump_info->CurrentFileName != NULL)
free(dump_info->CurrentFileName);
/* Allocate space for max filename + \0. */
dump_info->CurrentFileName = (char *)malloc(PATH_MAX + 1);
if (dump_info->CurrentFileName == NULL)
error("dump_packet_and_trunc: malloc");
/*
* This is always the first file in the Cflag
* rotation: e.g. 0
* We also don't need numbering if Cflag is not set.
*/
if (Cflag != 0)
MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0,
WflagChars);
else
MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, 0, 0);
#ifdef HAVE_CAP_NG_H
capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
capng_apply(CAPNG_EFFECTIVE);
#endif /* HAVE_CAP_NG_H */
#ifdef __FreeBSD__
fd = openat(dump_info->dirfd,
dump_info->CurrentFileName,
O_CREAT | O_WRONLY | O_TRUNC, 0644);
if (fd < 0) {
error("unable to open file %s",
dump_info->CurrentFileName);
}
fp = fdopen(fd, "w");
if (fp == NULL) {
error("unable to fdopen file %s",
dump_info->CurrentFileName);
}
dump_info->p = pcap_dump_fopen(dump_info->pd, fp);
#else /* !__FreeBSD__ */
dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
#endif
#ifdef HAVE_CAP_NG_H
capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
capng_apply(CAPNG_EFFECTIVE);
#endif /* HAVE_CAP_NG_H */
if (dump_info->p == NULL)
error("%s", pcap_geterr(pd));
#ifdef __FreeBSD__
cap_rights_init(&rights, CAP_SEEK, CAP_WRITE);
if (cap_rights_limit(fileno(pcap_dump_file(dump_info->p)),
&rights) < 0 && errno != ENOSYS) {
error("unable to limit dump descriptor");
}
#endif
}
}
/*
* XXX - this won't prevent capture files from getting
* larger than Cflag - the last packet written to the
* file could put it over Cflag.
*/
if (Cflag != 0 && pcap_dump_ftell(dump_info->p) > Cflag) {
#ifdef __FreeBSD__
FILE *fp;
int fd;
#endif
/*
* Close the current file and open a new one.
*/
pcap_dump_close(dump_info->p);
/*
* Compress the file we just closed, if the user asked for it
*/
if (zflag != NULL)
compress_savefile(dump_info->CurrentFileName);
Cflag_count++;
if (Wflag > 0) {
if (Cflag_count >= Wflag)
Cflag_count = 0;
}
if (dump_info->CurrentFileName != NULL)
free(dump_info->CurrentFileName);
dump_info->CurrentFileName = (char *)malloc(PATH_MAX + 1);
if (dump_info->CurrentFileName == NULL)
error("dump_packet_and_trunc: malloc");
MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, Cflag_count, WflagChars);
#ifdef __FreeBSD__
fd = openat(dump_info->dirfd, dump_info->CurrentFileName,
O_CREAT | O_WRONLY | O_TRUNC, 0644);
if (fd < 0) {
error("unable to open file %s",
dump_info->CurrentFileName);
}
fp = fdopen(fd, "w");
if (fp == NULL) {
error("unable to fdopen file %s",
dump_info->CurrentFileName);
}
dump_info->p = pcap_dump_fopen(dump_info->pd, fp);
#else /* !__FreeBSD__ */
dump_info->p = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
#endif
if (dump_info->p == NULL)
error("%s", pcap_geterr(pd));
#ifdef __FreeBSD__
cap_rights_init(&rights, CAP_SEEK, CAP_WRITE);
if (cap_rights_limit(fileno(pcap_dump_file(dump_info->p)),
&rights) < 0 && errno != ENOSYS) {
error("unable to limit dump descriptor");
}
#endif
}
pcap_dump((u_char *)dump_info->p, h, sp);
#ifdef HAVE_PCAP_DUMP_FLUSH
if (Uflag)
pcap_dump_flush(dump_info->p);
#endif
--infodelay;
if (infoprint)
info(0);
}
static void
dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
{
++packets_captured;
++infodelay;
pcap_dump(user, h, sp);
#ifdef HAVE_PCAP_DUMP_FLUSH
if (Uflag)
pcap_dump_flush((pcap_dumper_t *)user);
#endif
--infodelay;
if (infoprint)
info(0);
}
static void
print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
{
struct print_info *print_info;
u_int hdrlen;
++packets_captured;
++infodelay;
ts_print(&h->ts);
print_info = (struct print_info *)user;
/*
* Some printers want to check that they're not walking off the
* end of the packet.
* Rather than pass it all the way down, we set this global.
*/
snapend = sp + h->caplen;
if(print_info->ndo_type) {
hdrlen = (*print_info->p.ndo_printer)(print_info->ndo, h, sp);
} else {
hdrlen = (*print_info->p.printer)(h, sp);
}
if (Xflag) {
/*
* Print the raw packet data in hex and ASCII.
*/
if (Xflag > 1) {
/*
* Include the link-layer header.
*/
hex_and_ascii_print("\n\t", sp, h->caplen);
} else {
/*
* Don't include the link-layer header - and if
* we have nothing past the link-layer header,
* print nothing.
*/
if (h->caplen > hdrlen)
hex_and_ascii_print("\n\t", sp + hdrlen,
h->caplen - hdrlen);
}
} else if (xflag) {
/*
* Print the raw packet data in hex.
*/
if (xflag > 1) {
/*
* Include the link-layer header.
*/
hex_print("\n\t", sp, h->caplen);
} else {
/*
* Don't include the link-layer header - and if
* we have nothing past the link-layer header,
* print nothing.
*/
if (h->caplen > hdrlen)
hex_print("\n\t", sp + hdrlen,
h->caplen - hdrlen);
}
} else if (Aflag) {
/*
* Print the raw packet data in ASCII.
*/
if (Aflag > 1) {
/*
* Include the link-layer header.
*/
ascii_print(sp, h->caplen);
} else {
/*
* Don't include the link-layer header - and if
* we have nothing past the link-layer header,
* print nothing.
*/
if (h->caplen > hdrlen)
ascii_print(sp + hdrlen, h->caplen - hdrlen);
}
}
putchar('\n');
--infodelay;
if (infoprint)
info(0);
}
#ifdef WIN32
/*
* XXX - there should really be libpcap calls to get the version
* number as a string (the string would be generated from #defines
* at run time, so that it's not generated from string constants
* in the library, as, on many UNIX systems, those constants would
* be statically linked into the application executable image, and
* would thus reflect the version of libpcap on the system on
* which the application was *linked*, not the system on which it's
* *running*.
*
* That routine should be documented, unlike the "version[]"
* string, so that UNIX vendors providing their own libpcaps
* don't omit it (as a couple of vendors have...).
*
* Packet.dll should perhaps also export a routine to return the
* version number of the Packet.dll code, to supply the
* "Wpcap_version" information on Windows.
*/
char WDversion[]="current-cvs.tcpdump.org";
#if !defined(HAVE_GENERATED_VERSION)
char version[]="current-cvs.tcpdump.org";
#endif
char pcap_version[]="current-cvs.tcpdump.org";
char Wpcap_version[]="3.1";
#endif
/*
* By default, print the specified data out in hex and ASCII.
*/
static void
ndo_default_print(netdissect_options *ndo _U_, const u_char *bp, u_int length)
{
hex_and_ascii_print("\n\t", bp, length); /* pass on lf and identation string */
}
void
default_print(const u_char *bp, u_int length)
{
ndo_default_print(gndo, bp, length);
}
#ifdef SIGNAL_REQ_INFO
RETSIGTYPE requestinfo(int signo _U_)
{
if (infodelay)
++infoprint;
else
info(0);
}
#endif
/*
* Called once each second in verbose mode while dumping to file
*/
#ifdef USE_WIN32_MM_TIMER
void CALLBACK verbose_stats_dump (UINT timer_id _U_, UINT msg _U_, DWORD_PTR arg _U_,
DWORD_PTR dw1 _U_, DWORD_PTR dw2 _U_)
{
struct pcap_stat stat;
if (infodelay == 0 && pcap_stats(pd, &stat) >= 0)
fprintf(stderr, "Got %u\r", packets_captured);
}
#elif defined(HAVE_ALARM)
static void verbose_stats_dump(int sig _U_)
{
struct pcap_stat stat;
if (infodelay == 0 && pcap_stats(pd, &stat) >= 0)
fprintf(stderr, "Got %u\r", packets_captured);
alarm(1);
}
#endif
static void
usage(void)
{
extern char version[];
#ifndef HAVE_PCAP_LIB_VERSION
#if defined(WIN32) || defined(HAVE_PCAP_VERSION)
extern char pcap_version[];
#else /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
static char pcap_version[] = "unknown";
#endif /* defined(WIN32) || defined(HAVE_PCAP_VERSION) */
#endif /* HAVE_PCAP_LIB_VERSION */
#ifdef HAVE_PCAP_LIB_VERSION
#ifdef WIN32
(void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
#else /* WIN32 */
(void)fprintf(stderr, "%s version %s\n", program_name, version);
#endif /* WIN32 */
(void)fprintf(stderr, "%s\n",pcap_lib_version());
#else /* HAVE_PCAP_LIB_VERSION */
#ifdef WIN32
(void)fprintf(stderr, "%s version %s, based on tcpdump version %s\n", program_name, WDversion, version);
(void)fprintf(stderr, "WinPcap version %s, based on libpcap version %s\n",Wpcap_version, pcap_version);
#else /* WIN32 */
(void)fprintf(stderr, "%s version %s\n", program_name, version);
(void)fprintf(stderr, "libpcap version %s\n", pcap_version);
#endif /* WIN32 */
#endif /* HAVE_PCAP_LIB_VERSION */
(void)fprintf(stderr,
"Usage: %s [-aAbd" D_FLAG "efhH" I_FLAG J_FLAG "KlLnNOpqRStu" U_FLAG "vxX]" B_FLAG_USAGE " [ -c count ]\n", program_name);
(void)fprintf(stderr,
"\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n");
(void)fprintf(stderr,
"\t\t[ -i interface ]" j_FLAG_USAGE " [ -M secret ]\n");
(void)fprintf(stderr,
"\t\t[ -r file ] [ -s snaplen ] [ -T type ] [ -V file ] [ -w file ]\n");
(void)fprintf(stderr,
"\t\t[ -W filecount ] [ -y datalinktype ] [ -z command ]\n");
(void)fprintf(stderr,
"\t\t[ -Z user ] [ expression ]\n");
exit(1);
}
/* VARARGS */
static void
ndo_error(netdissect_options *ndo _U_, const char *fmt, ...)
{
va_list ap;
(void)fprintf(stderr, "%s: ", program_name);
va_start(ap, fmt);
(void)vfprintf(stderr, fmt, ap);
va_end(ap);
if (*fmt) {
fmt += strlen(fmt);
if (fmt[-1] != '\n')
(void)fputc('\n', stderr);
}
exit(1);
/* NOTREACHED */
}
/* VARARGS */
static void
ndo_warning(netdissect_options *ndo _U_, const char *fmt, ...)
{
va_list ap;
(void)fprintf(stderr, "%s: WARNING: ", program_name);
va_start(ap, fmt);
(void)vfprintf(stderr, fmt, ap);
va_end(ap);
if (*fmt) {
fmt += strlen(fmt);
if (fmt[-1] != '\n')
(void)fputc('\n', stderr);
}
}
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