Adding upstream version 4.99.3.upstream/4.99.3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 3234 insertions, 0 deletions

diff --git a/tcpdump.c b/tcpdump.c
new file mode 100644
index 0000000..78d0871
--- /dev/null
+++ b/tcpdump.c
@@ -0,0 +1,3234 @@
+/*
+ * 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>
+ */
+
+/*
+ * tcpdump - dump traffic on a network
+ *
+ * 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
+
+/*
+ * Some older versions of Mac OS X may ship pcap.h from libpcap 0.6 with a
+ * libpcap based on 0.8.  That means it has pcap_findalldevs() but the
+ * header doesn't define pcap_if_t, meaning that we can't actually *use*
+ * pcap_findalldevs().
+ */
+#ifdef HAVE_PCAP_FINDALLDEVS
+#ifndef HAVE_PCAP_IF_T
+#undef HAVE_PCAP_FINDALLDEVS
+#endif
+#endif
+
+#include "netdissect-stdinc.h"
+
+/*
+ * This must appear after including netdissect-stdinc.h, so that _U_ is
+ * defined.
+ */
+#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";
+#endif
+
+#include <sys/stat.h>
+
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+
+#ifdef HAVE_LIBCRYPTO
+#include <openssl/crypto.h>
+#endif
+
+#ifdef HAVE_GETOPT_LONG
+#include <getopt.h>
+#else
+#include "missing/getopt_long.h"
+#endif
+/* Capsicum-specific code requires macros from <net/bpf.h>, which will fail
+ * to compile if <pcap.h> has already been included; including the headers
+ * in the opposite order works fine. For the most part anyway, because in
+ * FreeBSD <pcap/pcap.h> declares bpf_dump() instead of <net/bpf.h>. Thus
+ * interface.h takes care of it later to avoid a compiler warning.
+ */
+#ifdef HAVE_CAPSICUM
+#include <sys/capsicum.h>
+#include <sys/ioccom.h>
+#include <net/bpf.h>
+#include <libgen.h>
+#ifdef HAVE_CASPER
+#include <libcasper.h>
+#include <casper/cap_dns.h>
+#include <sys/nv.h>
+#endif	/* HAVE_CASPER */
+#endif	/* HAVE_CAPSICUM */
+#ifdef HAVE_PCAP_OPEN
+/*
+ * We found pcap_open() in the capture library, so we'll be using
+ * the remote capture APIs; define PCAP_REMOTE before we include pcap.h,
+ * so we get those APIs declared, and the types and #defines that they
+ * use defined.
+ *
+ * WinPcap's headers require that PCAP_REMOTE be defined in order to get
+ * remote-capture APIs declared and types and #defines that they use
+ * defined.
+ *
+ * (Versions of libpcap with those APIs, and thus Npcap, which is based on
+ * those versions of libpcap, don't require it.)
+ */
+#define HAVE_REMOTE
+#endif
+#include <pcap.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+#ifdef _WIN32
+#include <windows.h>
+#else
+#include <sys/time.h>
+#include <sys/wait.h>
+#include <sys/resource.h>
+#include <pwd.h>
+#include <grp.h>
+#endif /* _WIN32 */
+
+/*
+ * Pathname separator.
+ * Use this in pathnames, but do *not* use it in URLs.
+ */
+#ifdef _WIN32
+#define PATH_SEPARATOR	'\\'
+#else
+#define PATH_SEPARATOR	'/'
+#endif
+
+/* capabilities convenience library */
+/* If a code depends on HAVE_LIBCAP_NG, it depends also on HAVE_CAP_NG_H.
+ * If HAVE_CAP_NG_H is not defined, undefine HAVE_LIBCAP_NG.
+ * Thus, the later tests are done only on HAVE_LIBCAP_NG.
+ */
+#ifdef HAVE_LIBCAP_NG
+#ifdef HAVE_CAP_NG_H
+#include <cap-ng.h>
+#else
+#undef HAVE_LIBCAP_NG
+#endif /* HAVE_CAP_NG_H */
+#endif /* HAVE_LIBCAP_NG */
+
+#ifdef __FreeBSD__
+#include <sys/sysctl.h>
+#endif /* __FreeBSD__ */
+
+#include "netdissect-stdinc.h"
+#include "netdissect.h"
+#include "interface.h"
+#include "addrtoname.h"
+#include "machdep.h"
+#include "pcap-missing.h"
+#include "ascii_strcasecmp.h"
+
+#include "print.h"
+
+#include "diag-control.h"
+
+#include "fptype.h"
+
+#ifndef PATH_MAX
+#define PATH_MAX 1024
+#endif
+
+#if defined(SIGINFO)
+#define SIGNAL_REQ_INFO SIGINFO
+#elif defined(SIGUSR1)
+#define SIGNAL_REQ_INFO SIGUSR1
+#endif
+
+#if defined(HAVE_PCAP_DUMP_FLUSH) && defined(SIGUSR2)
+#define SIGNAL_FLUSH_PCAP SIGUSR2
+#endif
+
+#if defined(HAVE_PCAP_CREATE) || defined(_WIN32)
+static int Bflag;			/* buffer size */
+#endif
+#ifdef HAVE_PCAP_DUMP_FTELL64
+static int64_t Cflag;			/* rotate dump files after this many bytes */
+#else
+static long Cflag;			/* rotate dump files after this many bytes */
+#endif
+static int Cflag_count;			/* Keep track of which file number we're writing */
+#ifdef HAVE_PCAP_FINDALLDEVS
+static int Dflag;			/* list available devices and exit */
+#endif
+#ifdef HAVE_PCAP_FINDALLDEVS_EX
+static char *remote_interfaces_source;	/* list available devices from this source and exit */
+#endif
+
+/*
+ * This is exported because, in some versions of libpcap, if libpcap
+ * is built with optimizer debugging code (which is *NOT* the default
+ * configuration!), the library *imports*(!) a variable named dflag,
+ * under the expectation that tcpdump is exporting it, to govern
+ * how much debugging information to print when optimizing
+ * the generated BPF code.
+ *
+ * This is a horrible hack; newer versions of libpcap don't import
+ * dflag but, instead, *if* built with optimizer debugging code,
+ * *export* a routine to set that flag.
+ */
+extern int dflag;
+int dflag;				/* print filter code */
+static int Gflag;			/* rotate dump files after this many seconds */
+static int Gflag_count;			/* number of files created with Gflag rotation */
+static time_t Gflag_time;		/* The last time_t the dump file was rotated. */
+static int Lflag;			/* list available data link types and exit */
+static int Iflag;			/* rfmon (monitor) mode */
+#ifdef HAVE_PCAP_SET_TSTAMP_TYPE
+static int Jflag;			/* list available time stamp types */
+static int jflag = -1;			/* packet time stamp source */
+#endif
+static int lflag;			/* line-buffered output */
+static int pflag;			/* don't go promiscuous */
+#ifdef HAVE_PCAP_SETDIRECTION
+static int Qflag = -1;			/* restrict captured packet by send/receive direction */
+#endif
+#ifdef HAVE_PCAP_DUMP_FLUSH
+static int Uflag;			/* "unbuffered" output of dump files */
+#endif
+static int Wflag;			/* recycle output files after this number of files */
+static int WflagChars;
+static char *zflag = NULL;		/* compress each savefile using a specified command (like gzip or bzip2) */
+static int timeout = 1000;		/* default timeout = 1000 ms = 1 s */
+#ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
+static int immediate_mode;
+#endif
+static int count_mode;
+
+static int infodelay;
+static int infoprint;
+
+char *program_name;
+
+/* Forwards */
+static NORETURN void error(FORMAT_STRING(const char *), ...) PRINTFLIKE(1, 2);
+static void warning(FORMAT_STRING(const char *), ...) PRINTFLIKE(1, 2);
+static NORETURN void exit_tcpdump(int);
+static void (*setsignal (int sig, void (*func)(int)))(int);
+static void cleanup(int);
+static void child_cleanup(int);
+static void print_version(FILE *);
+static void print_usage(FILE *);
+#ifdef HAVE_PCAP_SET_TSTAMP_TYPE
+static NORETURN void show_tstamp_types_and_exit(pcap_t *, const char *device);
+#endif
+static NORETURN void show_dlts_and_exit(pcap_t *, const char *device);
+#ifdef HAVE_PCAP_FINDALLDEVS
+static NORETURN void show_devices_and_exit(void);
+#endif
+#ifdef HAVE_PCAP_FINDALLDEVS_EX
+static NORETURN void show_remote_devices_and_exit(void);
+#endif
+
+static void print_packet(u_char *, const struct pcap_pkthdr *, const u_char *);
+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 *);
+
+#ifdef SIGNAL_REQ_INFO
+static void requestinfo(int);
+#endif
+
+#ifdef SIGNAL_FLUSH_PCAP
+static void flushpcap(int);
+#endif
+
+#ifdef _WIN32
+    static HANDLE timer_handle = INVALID_HANDLE_VALUE;
+    static void CALLBACK verbose_stats_dump(PVOID param, BOOLEAN timer_fired);
+#else /* _WIN32 */
+  static void verbose_stats_dump(int sig);
+#endif /* _WIN32 */
+
+static void info(int);
+static u_int packets_captured;
+
+#ifdef HAVE_PCAP_FINDALLDEVS
+static const struct tok status_flags[] = {
+#ifdef PCAP_IF_UP
+	{ PCAP_IF_UP,       "Up"       },
+#endif
+#ifdef PCAP_IF_RUNNING
+	{ PCAP_IF_RUNNING,  "Running"  },
+#endif
+	{ PCAP_IF_LOOPBACK, "Loopback" },
+#ifdef PCAP_IF_WIRELESS
+	{ PCAP_IF_WIRELESS, "Wireless" },
+#endif
+	{ 0, NULL }
+};
+#endif
+
+static pcap_t *pd;
+static pcap_dumper_t *pdd = NULL;
+
+static int supports_monitor_mode;
+
+extern int optind;
+extern int opterr;
+extern char *optarg;
+
+struct dump_info {
+	char	*WFileName;
+	char	*CurrentFileName;
+	pcap_t	*pd;
+	pcap_dumper_t *pdd;
+	netdissect_options *ndo;
+#ifdef HAVE_CAPSICUM
+	int	dirfd;
+#endif
+};
+
+#if defined(HAVE_PCAP_SET_PARSER_DEBUG)
+/*
+ * We have pcap_set_parser_debug() in libpcap; declare it (it's not declared
+ * by any libpcap header, because it's a special hack, only available if
+ * libpcap was configured to include it, and only intended for use by
+ * libpcap developers trying to debug the parser for filter expressions).
+ */
+#ifdef _WIN32
+__declspec(dllimport)
+#else /* _WIN32 */
+extern
+#endif /* _WIN32 */
+void pcap_set_parser_debug(int);
+#elif defined(HAVE_PCAP_DEBUG) || defined(HAVE_YYDEBUG)
+/*
+ * We don't have pcap_set_parser_debug() in libpcap, but we do have
+ * pcap_debug or yydebug.  Make a local version of pcap_set_parser_debug()
+ * to set the flag, and define HAVE_PCAP_SET_PARSER_DEBUG.
+ */
+static void
+pcap_set_parser_debug(int value)
+{
+#ifdef HAVE_PCAP_DEBUG
+	extern int pcap_debug;
+
+	pcap_debug = value;
+#else /* HAVE_PCAP_DEBUG */
+	extern int yydebug;
+
+	yydebug = value;
+#endif /* HAVE_PCAP_DEBUG */
+}
+
+#define HAVE_PCAP_SET_PARSER_DEBUG
+#endif
+
+#if defined(HAVE_PCAP_SET_OPTIMIZER_DEBUG)
+/*
+ * We have pcap_set_optimizer_debug() in libpcap; declare it (it's not declared
+ * by any libpcap header, because it's a special hack, only available if
+ * libpcap was configured to include it, and only intended for use by
+ * libpcap developers trying to debug the optimizer for filter expressions).
+ */
+#ifdef _WIN32
+__declspec(dllimport)
+#else /* _WIN32 */
+extern
+#endif /* _WIN32 */
+void pcap_set_optimizer_debug(int);
+#endif
+
+/* VARARGS */
+static void
+error(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_tcpdump(S_ERR_HOST_PROGRAM);
+	/* NOTREACHED */
+}
+
+/* VARARGS */
+static void
+warning(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);
+	}
+}
+
+static void
+exit_tcpdump(int status)
+{
+	nd_cleanup();
+	exit(status);
+}
+
+#ifdef HAVE_PCAP_SET_TSTAMP_TYPE
+static void
+show_tstamp_types_and_exit(pcap_t *pc, const char *device)
+{
+	int n_tstamp_types;
+	int *tstamp_types = 0;
+	const char *tstamp_type_name;
+	int i;
+
+	n_tstamp_types = pcap_list_tstamp_types(pc, &tstamp_types);
+	if (n_tstamp_types < 0)
+		error("%s", pcap_geterr(pc));
+
+	if (n_tstamp_types == 0) {
+		fprintf(stderr, "Time stamp type cannot be set for %s\n",
+		    device);
+		exit_tcpdump(S_SUCCESS);
+	}
+	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_tcpdump(S_SUCCESS);
+}
+#endif
+
+static void
+show_dlts_and_exit(pcap_t *pc, const char *device)
+{
+	int n_dlts, i;
+	int *dlts = 0;
+	const char *dlt_name;
+
+	n_dlts = pcap_list_datalinks(pc, &dlts);
+	if (n_dlts < 0)
+		error("%s", pcap_geterr(pc));
+	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);
+
+	for (i = 0; i < n_dlts; i++) {
+		dlt_name = pcap_datalink_val_to_name(dlts[i]);
+		if (dlt_name != NULL) {
+			(void) fprintf(stderr, "  %s (%s)", dlt_name,
+			    pcap_datalink_val_to_description(dlts[i]));
+
+			/*
+			 * OK, does tcpdump handle that type?
+			 */
+			if (!has_printer(dlts[i]))
+				(void) fprintf(stderr, " (printing not supported)");
+			fprintf(stderr, "\n");
+		} else {
+			(void) fprintf(stderr, "  DLT %d (printing not supported)\n",
+			    dlts[i]);
+		}
+	}
+#ifdef HAVE_PCAP_FREE_DATALINKS
+	pcap_free_datalinks(dlts);
+#endif
+	exit_tcpdump(S_SUCCESS);
+}
+
+#ifdef HAVE_PCAP_FINDALLDEVS
+static void
+show_devices_and_exit(void)
+{
+	pcap_if_t *dev, *devlist;
+	char ebuf[PCAP_ERRBUF_SIZE];
+	int i;
+
+	if (pcap_findalldevs(&devlist, ebuf) < 0)
+		error("%s", ebuf);
+	for (i = 0, dev = devlist; dev != NULL; i++, dev = dev->next) {
+		printf("%d.%s", i+1, dev->name);
+		if (dev->description != NULL)
+			printf(" (%s)", dev->description);
+		if (dev->flags != 0) {
+			printf(" [");
+			printf("%s", bittok2str(status_flags, "none", dev->flags));
+#ifdef PCAP_IF_WIRELESS
+			if (dev->flags & PCAP_IF_WIRELESS) {
+				switch (dev->flags & PCAP_IF_CONNECTION_STATUS) {
+
+				case PCAP_IF_CONNECTION_STATUS_UNKNOWN:
+					printf(", Association status unknown");
+					break;
+
+				case PCAP_IF_CONNECTION_STATUS_CONNECTED:
+					printf(", Associated");
+					break;
+
+				case PCAP_IF_CONNECTION_STATUS_DISCONNECTED:
+					printf(", Not associated");
+					break;
+
+				case PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE:
+					break;
+				}
+			} else {
+				switch (dev->flags & PCAP_IF_CONNECTION_STATUS) {
+
+				case PCAP_IF_CONNECTION_STATUS_UNKNOWN:
+					printf(", Connection status unknown");
+					break;
+
+				case PCAP_IF_CONNECTION_STATUS_CONNECTED:
+					printf(", Connected");
+					break;
+
+				case PCAP_IF_CONNECTION_STATUS_DISCONNECTED:
+					printf(", Disconnected");
+					break;
+
+				case PCAP_IF_CONNECTION_STATUS_NOT_APPLICABLE:
+					break;
+				}
+			}
+#endif
+			printf("]");
+		}
+		printf("\n");
+	}
+	pcap_freealldevs(devlist);
+	exit_tcpdump(S_SUCCESS);
+}
+#endif /* HAVE_PCAP_FINDALLDEVS */
+
+#ifdef HAVE_PCAP_FINDALLDEVS_EX
+static void
+show_remote_devices_and_exit(void)
+{
+	pcap_if_t *dev, *devlist;
+	char ebuf[PCAP_ERRBUF_SIZE];
+	int i;
+
+	if (pcap_findalldevs_ex(remote_interfaces_source, NULL, &devlist,
+	    ebuf) < 0)
+		error("%s", ebuf);
+	for (i = 0, dev = devlist; dev != NULL; i++, dev = dev->next) {
+		printf("%d.%s", i+1, dev->name);
+		if (dev->description != NULL)
+			printf(" (%s)", dev->description);
+		if (dev->flags != 0)
+			printf(" [%s]", bittok2str(status_flags, "none", dev->flags));
+		printf("\n");
+	}
+	pcap_freealldevs(devlist);
+	exit_tcpdump(S_SUCCESS);
+}
+#endif /* HAVE_PCAP_FINDALLDEVS */
+
+/*
+ * Short options.
+ *
+ * Note that there we use all letters for short options except for g, k,
+ * o, and P, and those are used by other versions of tcpdump, and we should
+ * only use them for the same purposes that the other versions of tcpdump
+ * use them:
+ *
+ * macOS tcpdump uses -g to force non--v output for IP to be on one
+ * line, making it more "g"repable;
+ *
+ * macOS tcpdump uses -k to specify that packet comments in pcapng files
+ * should be printed;
+ *
+ * OpenBSD tcpdump uses -o to indicate that OS fingerprinting should be done
+ * for hosts sending TCP SYN packets;
+ *
+ * macOS tcpdump uses -P to indicate that -w should write pcapng rather
+ * than pcap files.
+ *
+ * macOS tcpdump also uses -Q to specify expressions that match packet
+ * metadata, including but not limited to the packet direction.
+ * The expression syntax is different from a simple "in|out|inout",
+ * and those expressions aren't accepted by macOS tcpdump, but the
+ * equivalents would be "in" = "dir=in", "out" = "dir=out", and
+ * "inout" = "dir=in or dir=out", and the parser could conceivably
+ * special-case "in", "out", and "inout" as expressions for backwards
+ * compatibility, so all is not (yet) lost.
+ */
+
+/*
+ * 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_FINDALLDEVS
+#define D_FLAG	"D"
+#else
+#define D_FLAG
+#endif
+
+#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 USE_LIBSMI
+#define m_FLAG_USAGE "[ -m module ] ..."
+#endif
+
+#ifdef HAVE_PCAP_SETDIRECTION
+#define Q_FLAG "Q:"
+#define Q_FLAG_USAGE " [ -Q in|out|inout ]"
+#else
+#define Q_FLAG
+#define Q_FLAG_USAGE
+#endif
+
+#ifdef HAVE_PCAP_DUMP_FLUSH
+#define U_FLAG	"U"
+#else
+#define U_FLAG
+#endif
+
+#define SHORTOPTS "aAb" B_FLAG "c:C:d" D_FLAG "eE:fF:G:hHi:" I_FLAG j_FLAG J_FLAG "KlLm:M:nNOpq" Q_FLAG "r:s:StT:u" U_FLAG "vV:w:W:xXy:Yz:Z:#"
+
+/*
+ * Long options.
+ *
+ * We do not currently have long options corresponding to all short
+ * options; we should probably pick appropriate option names for them.
+ *
+ * However, the short options where the number of times the option is
+ * specified matters, such as -v and -d and -t, should probably not
+ * just map to a long option, as saying
+ *
+ *  tcpdump --verbose --verbose
+ *
+ * doesn't make sense; it should be --verbosity={N} or something such
+ * as that.
+ *
+ * For long options with no corresponding short options, we define values
+ * outside the range of ASCII graphic characters, make that the last
+ * component of the entry for the long option, and have a case for that
+ * option in the switch statement.
+ */
+#define OPTION_VERSION			128
+#define OPTION_TSTAMP_PRECISION		129
+#define OPTION_IMMEDIATE_MODE		130
+#define OPTION_PRINT			131
+#define OPTION_LIST_REMOTE_INTERFACES	132
+#define OPTION_TSTAMP_MICRO		133
+#define OPTION_TSTAMP_NANO		134
+#define OPTION_FP_TYPE			135
+#define OPTION_COUNT			136
+
+static const struct option longopts[] = {
+#if defined(HAVE_PCAP_CREATE) || defined(_WIN32)
+	{ "buffer-size", required_argument, NULL, 'B' },
+#endif
+	{ "list-interfaces", no_argument, NULL, 'D' },
+#ifdef HAVE_PCAP_FINDALLDEVS_EX
+	{ "list-remote-interfaces", required_argument, NULL, OPTION_LIST_REMOTE_INTERFACES },
+#endif
+	{ "help", no_argument, NULL, 'h' },
+	{ "interface", required_argument, NULL, 'i' },
+#ifdef HAVE_PCAP_CREATE
+	{ "monitor-mode", no_argument, NULL, 'I' },
+#endif
+#ifdef HAVE_PCAP_SET_TSTAMP_TYPE
+	{ "time-stamp-type", required_argument, NULL, 'j' },
+	{ "list-time-stamp-types", no_argument, NULL, 'J' },
+#endif
+#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
+	{ "micro", no_argument, NULL, OPTION_TSTAMP_MICRO},
+	{ "nano", no_argument, NULL, OPTION_TSTAMP_NANO},
+	{ "time-stamp-precision", required_argument, NULL, OPTION_TSTAMP_PRECISION},
+#endif
+	{ "dont-verify-checksums", no_argument, NULL, 'K' },
+	{ "list-data-link-types", no_argument, NULL, 'L' },
+	{ "no-optimize", no_argument, NULL, 'O' },
+	{ "no-promiscuous-mode", no_argument, NULL, 'p' },
+#ifdef HAVE_PCAP_SETDIRECTION
+	{ "direction", required_argument, NULL, 'Q' },
+#endif
+	{ "snapshot-length", required_argument, NULL, 's' },
+	{ "absolute-tcp-sequence-numbers", no_argument, NULL, 'S' },
+#ifdef HAVE_PCAP_DUMP_FLUSH
+	{ "packet-buffered", no_argument, NULL, 'U' },
+#endif
+	{ "linktype", required_argument, NULL, 'y' },
+#ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
+	{ "immediate-mode", no_argument, NULL, OPTION_IMMEDIATE_MODE },
+#endif
+#ifdef HAVE_PCAP_SET_PARSER_DEBUG
+	{ "debug-filter-parser", no_argument, NULL, 'Y' },
+#endif
+	{ "relinquish-privileges", required_argument, NULL, 'Z' },
+	{ "count", no_argument, NULL, OPTION_COUNT },
+	{ "fp-type", no_argument, NULL, OPTION_FP_TYPE },
+	{ "number", no_argument, NULL, '#' },
+	{ "print", no_argument, NULL, OPTION_PRINT },
+	{ "version", no_argument, NULL, OPTION_VERSION },
+	{ NULL, 0, NULL, 0 }
+};
+
+#ifdef HAVE_PCAP_FINDALLDEVS_EX
+#define LIST_REMOTE_INTERFACES_USAGE "[ --list-remote-interfaces remote-source ]"
+#else
+#define LIST_REMOTE_INTERFACES_USAGE
+#endif
+
+#ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
+#define IMMEDIATE_MODE_USAGE " [ --immediate-mode ]"
+#else
+#define IMMEDIATE_MODE_USAGE ""
+#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)
+		error("Chroot without dropping root is insecure");
+
+	pw = getpwnam(username);
+	if (pw) {
+		if (chroot_dir) {
+			if (chroot(chroot_dir) != 0 || chdir ("/") != 0)
+				error("Couldn't chroot/chdir to '%.64s': %s",
+				      chroot_dir, pcap_strerror(errno));
+		}
+#ifdef HAVE_LIBCAP_NG
+		{
+			int ret = capng_change_id(pw->pw_uid, pw->pw_gid, CAPNG_NO_FLAG);
+			if (ret < 0)
+				error("capng_change_id(): return %d\n", ret);
+			else
+				fprintf(stderr, "dropped privs to %s\n", username);
+		}
+#else
+		if (initgroups(pw->pw_name, pw->pw_gid) != 0 ||
+		    setgid(pw->pw_gid) != 0 || setuid(pw->pw_uid) != 0)
+			error("Couldn't change to '%.32s' uid=%lu gid=%lu: %s",
+				username,
+				(unsigned long)pw->pw_uid,
+				(unsigned long)pw->pw_gid,
+				pcap_strerror(errno));
+		else {
+			fprintf(stderr, "dropped privs to %s\n", username);
+		}
+#endif /* HAVE_LIBCAP_NG */
+	} else
+		error("Couldn't find user '%.32s'", username);
+#ifdef HAVE_LIBCAP_NG
+	/* We don't need CAP_SETUID, CAP_SETGID and CAP_SYS_CHROOT any more. */
+DIAG_OFF_ASSIGN_ENUM
+	capng_updatev(
+		CAPNG_DROP,
+		CAPNG_EFFECTIVE | CAPNG_PERMITTED,
+		CAP_SETUID,
+		CAP_SETGID,
+		CAP_SYS_CHROOT,
+		-1);
+DIAG_ON_ASSIGN_ENUM
+	capng_apply(CAPNG_SELECT_BOTH);
+#endif /* HAVE_LIBCAP_NG */
+
+}
+#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("%s: malloc", __func__);
+
+        /* 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("%s: localtime", __func__);
+          }
+
+          /* 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 char *
+get_next_file(FILE *VFile, char *ptr)
+{
+	char *ret;
+	size_t len;
+
+	ret = fgets(ptr, PATH_MAX, VFile);
+	if (!ret)
+		return NULL;
+
+	len = strlen (ptr);
+	if (len > 0 && ptr[len - 1] == '\n')
+		ptr[len - 1] = '\0';
+
+	return ret;
+}
+
+#ifdef HAVE_CASPER
+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)
+		error("unable to create casper process");
+	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_CASPER */
+
+#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
+static int
+tstamp_precision_from_string(const char *precision)
+{
+	if (strncmp(precision, "nano", strlen("nano")) == 0)
+		return PCAP_TSTAMP_PRECISION_NANO;
+
+	if (strncmp(precision, "micro", strlen("micro")) == 0)
+		return PCAP_TSTAMP_PRECISION_MICRO;
+
+	return -EINVAL;
+}
+
+static const char *
+tstamp_precision_to_string(int precision)
+{
+	switch (precision) {
+
+	case PCAP_TSTAMP_PRECISION_MICRO:
+		return "micro";
+
+	case PCAP_TSTAMP_PRECISION_NANO:
+		return "nano";
+
+	default:
+		return "unknown";
+	}
+}
+#endif
+
+#ifdef HAVE_CAPSICUM
+/*
+ * Ensure that, on a dump file's descriptor, we have all the rights
+ * necessary to make the standard I/O library work with an fdopen()ed
+ * FILE * from that descriptor.
+ *
+ * A long time ago in a galaxy far, far away, AT&T decided that, instead
+ * of providing separate APIs for getting and setting the FD_ flags on a
+ * descriptor, getting and setting the O_ flags on a descriptor, and
+ * locking files, they'd throw them all into a kitchen-sink fcntl() call
+ * along the lines of ioctl(), the fact that ioctl() operations are
+ * largely specific to particular character devices but fcntl() operations
+ * are either generic to all descriptors or generic to all descriptors for
+ * regular files nonwithstanding.
+ *
+ * The Capsicum people decided that fine-grained control of descriptor
+ * operations was required, so that you need to grant permission for
+ * reading, writing, seeking, and fcntl-ing.  The latter, courtesy of
+ * AT&T's decision, means that "fcntl-ing" isn't a thing, but a motley
+ * collection of things, so there are *individual* fcntls for which
+ * permission needs to be granted.
+ *
+ * The FreeBSD standard I/O people implemented some optimizations that
+ * requires that the standard I/O routines be able to determine whether
+ * the descriptor for the FILE * is open append-only or not; as that
+ * descriptor could have come from an open() rather than an fopen(),
+ * that requires that it be able to do an F_GETFL fcntl() to read
+ * the O_ flags.
+ *
+ * Tcpdump uses ftell() to determine how much data has been written
+ * to a file in order to, when used with -C, determine when it's time
+ * to rotate capture files.  ftell() therefore needs to do an lseek()
+ * to find out the file offset and must, thanks to the aforementioned
+ * optimization, also know whether the descriptor is open append-only
+ * or not.
+ *
+ * The net result of all the above is that we need to grant CAP_SEEK,
+ * CAP_WRITE, and CAP_FCNTL with the CAP_FCNTL_GETFL subcapability.
+ *
+ * Perhaps this is the universe's way of saying that either
+ *
+ *	1) there needs to be an fopenat() call and a pcap_dump_openat() call
+ *	   using it, so that Capsicum-capable tcpdump wouldn't need to do
+ *	   an fdopen()
+ *
+ * or
+ *
+ *	2) there needs to be a cap_fdopen() call in the FreeBSD standard
+ *	   I/O library that knows what rights are needed by the standard
+ *	   I/O library, based on the open mode, and assigns them, perhaps
+ *	   with an additional argument indicating, for example, whether
+ *	   seeking should be allowed, so that tcpdump doesn't need to know
+ *	   what the standard I/O library happens to require this week.
+ */
+static void
+set_dumper_capsicum_rights(pcap_dumper_t *p)
+{
+	int fd = fileno(pcap_dump_file(p));
+	cap_rights_t rights;
+
+	cap_rights_init(&rights, CAP_SEEK, CAP_WRITE, CAP_FCNTL);
+	if (cap_rights_limit(fd, &rights) < 0 && errno != ENOSYS) {
+		error("unable to limit dump descriptor");
+	}
+	if (cap_fcntls_limit(fd, CAP_FCNTL_GETFL) < 0 && errno != ENOSYS) {
+		error("unable to limit dump descriptor fcntls");
+	}
+}
+#endif
+
+/*
+ * Copy arg vector into a new buffer, concatenating arguments with spaces.
+ */
+static char *
+copy_argv(char **argv)
+{
+	char **p;
+	size_t len = 0;
+	char *buf;
+	char *src, *dst;
+
+	p = argv;
+	if (*p == NULL)
+		return 0;
+
+	while (*p)
+		len += strlen(*p++) + 1;
+
+	buf = (char *)malloc(len);
+	if (buf == NULL)
+		error("%s: malloc", __func__);
+
+	p = argv;
+	dst = buf;
+	while ((src = *p++) != NULL) {
+		while ((*dst++ = *src++) != '\0')
+			;
+		dst[-1] = ' ';
+	}
+	dst[-1] = '\0';
+
+	return buf;
+}
+
+/*
+ * On Windows, we need to open the file in binary mode, so that
+ * we get all the bytes specified by the size we get from "fstat()".
+ * On UNIX, that's not necessary.  O_BINARY is defined on Windows;
+ * we define it as 0 if it's not defined, so it does nothing.
+ */
+#ifndef O_BINARY
+#define O_BINARY	0
+#endif
+
+static char *
+read_infile(char *fname)
+{
+	int i, fd;
+	ssize_t cc;
+	char *cp;
+	our_statb buf;
+
+	fd = open(fname, O_RDONLY|O_BINARY);
+	if (fd < 0)
+		error("can't open %s: %s", fname, pcap_strerror(errno));
+
+	if (our_fstat(fd, &buf) < 0)
+		error("can't stat %s: %s", fname, pcap_strerror(errno));
+
+	/*
+	 * Reject files whose size doesn't fit into an int; a filter
+	 * *that* large will probably be too big.
+	 */
+	if (buf.st_size > INT_MAX)
+		error("%s is too large", fname);
+
+	cp = malloc((u_int)buf.st_size + 1);
+	if (cp == NULL)
+		error("malloc(%d) for %s: %s", (u_int)buf.st_size + 1,
+			fname, pcap_strerror(errno));
+	cc = read(fd, cp, (u_int)buf.st_size);
+	if (cc < 0)
+		error("read %s: %s", fname, pcap_strerror(errno));
+	if (cc != buf.st_size)
+		error("short read %s (%d != %d)", fname, (int) cc,
+		    (int)buf.st_size);
+
+	close(fd);
+	/* replace "# comment" with spaces */
+	for (i = 0; i < cc; i++) {
+		if (cp[i] == '#')
+			while (i < cc && cp[i] != '\n')
+				cp[i++] = ' ';
+	}
+	cp[cc] = '\0';
+	return (cp);
+}
+
+#ifdef HAVE_PCAP_FINDALLDEVS
+static long
+parse_interface_number(const char *device)
+{
+	const char *p;
+	long devnum;
+	char *end;
+
+	/*
+	 * Search for a colon, terminating any scheme at the beginning
+	 * of the device.
+	 */
+	p = strchr(device, ':');
+	if (p != NULL) {
+		/*
+		 * We found it.  Is it followed by "//"?
+		 */
+		p++;	/* skip the : */
+		if (strncmp(p, "//", 2) == 0) {
+			/*
+			 * Yes.  Search for the next /, at the end of the
+			 * authority part of the URL.
+			 */
+			p += 2;	/* skip the // */
+			p = strchr(p, '/');
+			if (p != NULL) {
+				/*
+				 * OK, past the / is the path.
+				 */
+				device = p + 1;
+			}
+		}
+	}
+	devnum = strtol(device, &end, 10);
+	if (device != end && *end == '\0') {
+		/*
+		 * It's all-numeric, but is it a valid number?
+		 */
+		if (devnum <= 0) {
+			/*
+			 * No, it's not an ordinal.
+			 */
+			error("Invalid adapter index");
+		}
+		return (devnum);
+	} else {
+		/*
+		 * It's not all-numeric; return -1, so our caller
+		 * knows that.
+		 */
+		return (-1);
+	}
+}
+
+static char *
+find_interface_by_number(const char *url
+#ifndef HAVE_PCAP_FINDALLDEVS_EX
+_U_
+#endif
+, long devnum)
+{
+	pcap_if_t *dev, *devlist;
+	long i;
+	char ebuf[PCAP_ERRBUF_SIZE];
+	char *device;
+#ifdef HAVE_PCAP_FINDALLDEVS_EX
+	const char *endp;
+	char *host_url;
+#endif
+	int status;
+
+#ifdef HAVE_PCAP_FINDALLDEVS_EX
+	/*
+	 * Search for a colon, terminating any scheme at the beginning
+	 * of the URL.
+	 */
+	endp = strchr(url, ':');
+	if (endp != NULL) {
+		/*
+		 * We found it.  Is it followed by "//"?
+		 */
+		endp++;	/* skip the : */
+		if (strncmp(endp, "//", 2) == 0) {
+			/*
+			 * Yes.  Search for the next /, at the end of the
+			 * authority part of the URL.
+			 */
+			endp += 2;	/* skip the // */
+			endp = strchr(endp, '/');
+		} else
+			endp = NULL;
+	}
+	if (endp != NULL) {
+		/*
+		 * OK, everything from device to endp is a URL to hand
+		 * to pcap_findalldevs_ex().
+		 */
+		endp++;	/* Include the trailing / in the URL; pcap_findalldevs_ex() requires it */
+		host_url = malloc(endp - url + 1);
+		if (host_url == NULL && (endp - url + 1) > 0)
+			error("Invalid allocation for host");
+
+		memcpy(host_url, url, endp - url);
+		host_url[endp - url] = '\0';
+		status = pcap_findalldevs_ex(host_url, NULL, &devlist, ebuf);
+		free(host_url);
+	} else
+#endif
+	status = pcap_findalldevs(&devlist, ebuf);
+	if (status < 0)
+		error("%s", ebuf);
+	/*
+	 * Look for the devnum-th entry in the list of devices (1-based).
+	 */
+	for (i = 0, dev = devlist; i < devnum-1 && dev != NULL;
+	    i++, dev = dev->next)
+		;
+	if (dev == NULL)
+		error("Invalid adapter index");
+	device = strdup(dev->name);
+	pcap_freealldevs(devlist);
+	return (device);
+}
+#endif
+
+#ifdef HAVE_PCAP_OPEN
+/*
+ * Prefixes for rpcap URLs.
+ */
+static char rpcap_prefix[] = "rpcap://";
+static char rpcap_ssl_prefix[] = "rpcaps://";
+#endif
+
+static pcap_t *
+open_interface(const char *device, netdissect_options *ndo, char *ebuf)
+{
+	pcap_t *pc;
+#ifdef HAVE_PCAP_CREATE
+	int status;
+	char *cp;
+#endif
+
+#ifdef HAVE_PCAP_OPEN
+	/*
+	 * Is this an rpcap URL?
+	 */
+	if (strncmp(device, rpcap_prefix, sizeof(rpcap_prefix) - 1) == 0 ||
+	    strncmp(device, rpcap_ssl_prefix, sizeof(rpcap_ssl_prefix) - 1) == 0) {
+		/*
+		 * Yes.  Open it with pcap_open().
+		 */
+		*ebuf = '\0';
+		pc = pcap_open(device, ndo->ndo_snaplen,
+		    pflag ? 0 : PCAP_OPENFLAG_PROMISCUOUS, timeout, NULL,
+		    ebuf);
+		if (pc == NULL) {
+			/*
+			 * If this failed with "No such device" or "The system
+			 * cannot find the device specified", that means
+			 * the interface doesn't exist; return NULL, so that
+			 * the caller can see whether the device name is
+			 * actually an interface index.
+			 */
+			if (strstr(ebuf, "No such device") != NULL ||
+			    strstr(ebuf, "The system cannot find the device specified") != NULL)
+				return (NULL);
+			error("%s", ebuf);
+		}
+		if (*ebuf)
+			warning("%s", ebuf);
+		return (pc);
+	}
+#endif /* HAVE_PCAP_OPEN */
+
+#ifdef HAVE_PCAP_CREATE
+	pc = pcap_create(device, ebuf);
+	if (pc == NULL) {
+		/*
+		 * If this failed with "No such device", that means
+		 * the interface doesn't exist; return NULL, so that
+		 * the caller can see whether the device name is
+		 * actually an interface index.
+		 */
+		if (strstr(ebuf, "No such device") != NULL)
+			return (NULL);
+		error("%s", ebuf);
+	}
+#ifdef HAVE_PCAP_SET_TSTAMP_TYPE
+	if (Jflag)
+		show_tstamp_types_and_exit(pc, device);
+#endif
+#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
+	status = pcap_set_tstamp_precision(pc, ndo->ndo_tstamp_precision);
+	if (status != 0)
+		error("%s: Can't set %ssecond time stamp precision: %s",
+		    device,
+		    tstamp_precision_to_string(ndo->ndo_tstamp_precision),
+		    pcap_statustostr(status));
+#endif
+
+#ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
+	if (immediate_mode) {
+		status = pcap_set_immediate_mode(pc, 1);
+		if (status != 0)
+			error("%s: Can't set immediate mode: %s",
+			    device, pcap_statustostr(status));
+	}
+#endif
+	/*
+	 * Is this an interface that supports monitor mode?
+	 */
+	if (pcap_can_set_rfmon(pc) == 1)
+		supports_monitor_mode = 1;
+	else
+		supports_monitor_mode = 0;
+	if (ndo->ndo_snaplen != 0) {
+		/*
+		 * A snapshot length was explicitly specified;
+		 * use it.
+		 */
+		status = pcap_set_snaplen(pc, ndo->ndo_snaplen);
+		if (status != 0)
+			error("%s: Can't set snapshot length: %s",
+			    device, pcap_statustostr(status));
+	}
+	status = pcap_set_promisc(pc, !pflag);
+	if (status != 0)
+		error("%s: Can't set promiscuous mode: %s",
+		    device, pcap_statustostr(status));
+	if (Iflag) {
+		status = pcap_set_rfmon(pc, 1);
+		if (status != 0)
+			error("%s: Can't set monitor mode: %s",
+			    device, pcap_statustostr(status));
+	}
+	status = pcap_set_timeout(pc, timeout);
+	if (status != 0)
+		error("%s: pcap_set_timeout failed: %s",
+		    device, pcap_statustostr(status));
+	if (Bflag != 0) {
+		status = pcap_set_buffer_size(pc, 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(pc, jflag);
+		if (status < 0)
+			error("%s: Can't set time stamp type: %s",
+			    device, pcap_statustostr(status));
+		else if (status > 0)
+			warning("When trying to set timestamp type '%s' on %s: %s",
+			    pcap_tstamp_type_val_to_name(jflag), device,
+			    pcap_statustostr(status));
+	}
+#endif
+	status = pcap_activate(pc);
+	if (status < 0) {
+		/*
+		 * pcap_activate() failed.
+		 */
+		cp = pcap_geterr(pc);
+		if (status == PCAP_ERROR)
+			error("%s", cp);
+		else if (status == PCAP_ERROR_NO_SUCH_DEVICE) {
+			/*
+			 * Return an error for our caller to handle.
+			 */
+			snprintf(ebuf, PCAP_ERRBUF_SIZE, "%s: %s\n(%s)",
+			    device, pcap_statustostr(status), cp);
+		} else if (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. */
+			/* FIXME: incrementing the index this way is not going to work well
+			 * when the index is 9 or greater but the only consequence in this
+			 * specific case would be an error message that looks a bit odd.
+			 */
+			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\n"
+			    "and use %s as the tcpdump interface",
+			    device, newdev, parent, newdev);
+		}
+#endif
+		else
+			error("%s: %s", device,
+			    pcap_statustostr(status));
+		pcap_close(pc);
+		return (NULL);
+	} else if (status > 0) {
+		/*
+		 * pcap_activate() succeeded, but it's warning us
+		 * of a problem it had.
+		 */
+		cp = pcap_geterr(pc);
+		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));
+	}
+#ifdef HAVE_PCAP_SETDIRECTION
+	if (Qflag != -1) {
+		status = pcap_setdirection(pc, Qflag);
+		if (status != 0)
+			error("%s: pcap_setdirection() failed: %s",
+			      device,  pcap_geterr(pc));
+		}
+#endif /* HAVE_PCAP_SETDIRECTION */
+#else /* HAVE_PCAP_CREATE */
+	*ebuf = '\0';
+	/*
+	 * If no snapshot length was specified, or a length of 0 was
+	 * specified, default to 256KB.
+	 */
+	if (ndo->ndo_snaplen == 0)
+		ndo->ndo_snaplen = MAXIMUM_SNAPLEN;
+	pc = pcap_open_live(device, ndo->ndo_snaplen, !pflag, timeout, ebuf);
+	if (pc == NULL) {
+		/*
+		 * If this failed with "No such device", that means
+		 * the interface doesn't exist; return NULL, so that
+		 * the caller can see whether the device name is
+		 * actually an interface index.
+		 */
+		if (strstr(ebuf, "No such device") != NULL)
+			return (NULL);
+		error("%s", ebuf);
+	}
+	if (*ebuf)
+		warning("%s", ebuf);
+#endif /* HAVE_PCAP_CREATE */
+
+	return (pc);
+}
+
+int
+main(int argc, char **argv)
+{
+	int cnt, op, i;
+	bpf_u_int32 localnet = 0, netmask = 0;
+	char *cp, *infile, *cmdbuf, *device, *RFileName, *VFileName, *WFileName;
+	char *endp;
+	pcap_handler callback;
+	int dlt;
+	const char *dlt_name;
+	struct bpf_program fcode;
+#ifndef _WIN32
+	void (*oldhandler)(int);
+#endif
+	struct dump_info dumpinfo;
+	u_char *pcap_userdata;
+	char ebuf[PCAP_ERRBUF_SIZE];
+	char VFileLine[PATH_MAX + 1];
+	const char *username = NULL;
+#ifndef _WIN32
+	const char *chroot_dir = NULL;
+#endif
+	char *ret = NULL;
+	char *end;
+#ifdef HAVE_PCAP_FINDALLDEVS
+	pcap_if_t *devlist;
+	long devnum;
+#endif
+	int status;
+	FILE *VFile;
+#ifdef HAVE_CAPSICUM
+	cap_rights_t rights;
+	int cansandbox;
+#endif	/* HAVE_CAPSICUM */
+	int Oflag = 1;			/* run filter code optimizer */
+	int yflag_dlt = -1;
+	const char *yflag_dlt_name = NULL;
+	int print = 0;
+
+	netdissect_options Ndo;
+	netdissect_options *ndo = &Ndo;
+
+	/*
+	 * Initialize the netdissect code.
+	 */
+	if (nd_init(ebuf, sizeof(ebuf)) == -1)
+		error("%s", ebuf);
+
+	memset(ndo, 0, sizeof(*ndo));
+	ndo_set_function_pointers(ndo);
+
+	cnt = -1;
+	device = NULL;
+	infile = NULL;
+	RFileName = NULL;
+	VFileName = NULL;
+	VFile = NULL;
+	WFileName = NULL;
+	dlt = -1;
+	if ((cp = strrchr(argv[0], PATH_SEPARATOR)) != NULL)
+		ndo->program_name = program_name = cp + 1;
+	else
+		ndo->program_name = program_name = argv[0];
+
+#if defined(HAVE_PCAP_WSOCKINIT)
+	if (pcap_wsockinit() != 0)
+		error("Attempting to initialize Winsock failed");
+#elif defined(HAVE_WSOCKINIT)
+	if (wsockinit() != 0)
+		error("Attempting to initialize Winsock failed");
+#endif
+
+	/*
+	 * On platforms where the CPU doesn't support unaligned loads,
+	 * force unaligned accesses to abort with SIGBUS, rather than
+	 * being fixed up (slowly) by the OS kernel; on those platforms,
+	 * misaligned accesses are bugs, and we want tcpdump to crash so
+	 * that the bugs are reported.
+	 */
+	if (abort_on_misalignment(ebuf, sizeof(ebuf)) < 0)
+		error("%s", ebuf);
+
+	while (
+	    (op = getopt_long(argc, argv, SHORTOPTS, longopts, NULL)) != -1)
+		switch (op) {
+
+		case 'a':
+			/* compatibility for old -a */
+			break;
+
+		case 'A':
+			++ndo->ndo_Aflag;
+			break;
+
+		case 'b':
+			++ndo->ndo_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':
+			errno = 0;
+#ifdef HAVE_PCAP_DUMP_FTELL64
+			Cflag = strtoint64_t(optarg, &endp, 10);
+#else
+			Cflag = strtol(optarg, &endp, 10);
+#endif
+			if (endp == optarg || *endp != '\0' || errno != 0
+			    || Cflag <= 0)
+				error("invalid file size %s", optarg);
+			/*
+			 * Will multiplying it by 1000000 overflow?
+			 */
+#ifdef HAVE_PCAP_DUMP_FTELL64
+			if (Cflag > INT64_T_CONSTANT(0x7fffffffffffffff) / 1000000)
+#else
+			if (Cflag > LONG_MAX / 1000000)
+#endif
+				error("file size %s is too large", optarg);
+			Cflag *= 1000000;
+			break;
+
+		case 'd':
+			++dflag;
+			break;
+
+#ifdef HAVE_PCAP_FINDALLDEVS
+		case 'D':
+			Dflag++;
+			break;
+#endif
+
+#ifdef HAVE_PCAP_FINDALLDEVS_EX
+		case OPTION_LIST_REMOTE_INTERFACES:
+			remote_interfaces_source = optarg;
+			break;
+#endif
+
+		case 'L':
+			Lflag++;
+			break;
+
+		case 'e':
+			++ndo->ndo_eflag;
+			break;
+
+		case 'E':
+#ifndef HAVE_LIBCRYPTO
+			warning("crypto code not compiled in");
+#endif
+			ndo->ndo_espsecret = optarg;
+			break;
+
+		case 'f':
+			++ndo->ndo_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("%s: can't get current time: %s",
+				    __func__, pcap_strerror(errno));
+			}
+			break;
+
+		case 'h':
+			print_usage(stdout);
+			exit_tcpdump(S_SUCCESS);
+			break;
+
+		case 'H':
+			++ndo->ndo_Hflag;
+			break;
+
+		case 'i':
+			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 */
+			lflag = 1;
+			break;
+
+		case 'K':
+			++ndo->ndo_Kflag;
+			break;
+
+		case 'm':
+			if (nd_have_smi_support()) {
+				if (nd_load_smi_module(optarg, ebuf, sizeof(ebuf)) == -1)
+					error("%s", ebuf);
+			} else {
+				(void)fprintf(stderr, "%s: ignoring option `-m %s' ",
+					      program_name, optarg);
+				(void)fprintf(stderr, "(no libsmi support)\n");
+			}
+			break;
+
+		case 'M':
+			/* TCP-MD5 shared secret */
+#ifndef HAVE_LIBCRYPTO
+			warning("crypto code not compiled in");
+#endif
+			ndo->ndo_sigsecret = optarg;
+			break;
+
+		case 'n':
+			++ndo->ndo_nflag;
+			break;
+
+		case 'N':
+			++ndo->ndo_Nflag;
+			break;
+
+		case 'O':
+			Oflag = 0;
+			break;
+
+		case 'p':
+			++pflag;
+			break;
+
+		case 'q':
+			++ndo->ndo_qflag;
+			++ndo->ndo_suppress_default_print;
+			break;
+
+#ifdef HAVE_PCAP_SETDIRECTION
+		case 'Q':
+			if (ascii_strcasecmp(optarg, "in") == 0)
+				Qflag = PCAP_D_IN;
+			else if (ascii_strcasecmp(optarg, "out") == 0)
+				Qflag = PCAP_D_OUT;
+			else if (ascii_strcasecmp(optarg, "inout") == 0)
+				Qflag = PCAP_D_INOUT;
+			else
+				error("unknown capture direction `%s'", optarg);
+			break;
+#endif /* HAVE_PCAP_SETDIRECTION */
+
+		case 'r':
+			RFileName = optarg;
+			break;
+
+		case 's':
+			ndo->ndo_snaplen = (int)strtol(optarg, &end, 0);
+			if (optarg == end || *end != '\0'
+			    || ndo->ndo_snaplen < 0 || ndo->ndo_snaplen > MAXIMUM_SNAPLEN)
+				error("invalid snaplen %s (must be >= 0 and <= %d)",
+				      optarg, MAXIMUM_SNAPLEN);
+			break;
+
+		case 'S':
+			++ndo->ndo_Sflag;
+			break;
+
+		case 't':
+			++ndo->ndo_tflag;
+			break;
+
+		case 'T':
+			if (ascii_strcasecmp(optarg, "vat") == 0)
+				ndo->ndo_packettype = PT_VAT;
+			else if (ascii_strcasecmp(optarg, "wb") == 0)
+				ndo->ndo_packettype = PT_WB;
+			else if (ascii_strcasecmp(optarg, "rpc") == 0)
+				ndo->ndo_packettype = PT_RPC;
+			else if (ascii_strcasecmp(optarg, "rtp") == 0)
+				ndo->ndo_packettype = PT_RTP;
+			else if (ascii_strcasecmp(optarg, "rtcp") == 0)
+				ndo->ndo_packettype = PT_RTCP;
+			else if (ascii_strcasecmp(optarg, "snmp") == 0)
+				ndo->ndo_packettype = PT_SNMP;
+			else if (ascii_strcasecmp(optarg, "cnfp") == 0)
+				ndo->ndo_packettype = PT_CNFP;
+			else if (ascii_strcasecmp(optarg, "tftp") == 0)
+				ndo->ndo_packettype = PT_TFTP;
+			else if (ascii_strcasecmp(optarg, "aodv") == 0)
+				ndo->ndo_packettype = PT_AODV;
+			else if (ascii_strcasecmp(optarg, "carp") == 0)
+				ndo->ndo_packettype = PT_CARP;
+			else if (ascii_strcasecmp(optarg, "radius") == 0)
+				ndo->ndo_packettype = PT_RADIUS;
+			else if (ascii_strcasecmp(optarg, "zmtp1") == 0)
+				ndo->ndo_packettype = PT_ZMTP1;
+			else if (ascii_strcasecmp(optarg, "vxlan") == 0)
+				ndo->ndo_packettype = PT_VXLAN;
+			else if (ascii_strcasecmp(optarg, "pgm") == 0)
+				ndo->ndo_packettype = PT_PGM;
+			else if (ascii_strcasecmp(optarg, "pgm_zmtp1") == 0)
+				ndo->ndo_packettype = PT_PGM_ZMTP1;
+			else if (ascii_strcasecmp(optarg, "lmp") == 0)
+				ndo->ndo_packettype = PT_LMP;
+			else if (ascii_strcasecmp(optarg, "resp") == 0)
+				ndo->ndo_packettype = PT_RESP;
+			else if (ascii_strcasecmp(optarg, "ptp") == 0)
+				ndo->ndo_packettype = PT_PTP;
+			else if (ascii_strcasecmp(optarg, "someip") == 0)
+				ndo->ndo_packettype = PT_SOMEIP;
+			else if (ascii_strcasecmp(optarg, "domain") == 0)
+				ndo->ndo_packettype = PT_DOMAIN;
+			else
+				error("unknown packet type `%s'", optarg);
+			break;
+
+		case 'u':
+			++ndo->ndo_uflag;
+			break;
+
+#ifdef HAVE_PCAP_DUMP_FLUSH
+		case 'U':
+			++Uflag;
+			break;
+#endif
+
+		case 'v':
+			++ndo->ndo_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':
+			++ndo->ndo_xflag;
+			++ndo->ndo_suppress_default_print;
+			break;
+
+		case 'X':
+			++ndo->ndo_Xflag;
+			++ndo->ndo_suppress_default_print;
+			break;
+
+		case 'y':
+			yflag_dlt_name = optarg;
+			yflag_dlt =
+				pcap_datalink_name_to_val(yflag_dlt_name);
+			if (yflag_dlt < 0)
+				error("invalid data link type %s", yflag_dlt_name);
+			break;
+
+#ifdef HAVE_PCAP_SET_PARSER_DEBUG
+		case 'Y':
+			{
+			/* Undocumented flag */
+			pcap_set_parser_debug(1);
+			}
+			break;
+#endif
+		case 'z':
+			zflag = optarg;
+			break;
+
+		case 'Z':
+			username = optarg;
+			break;
+
+		case '#':
+			ndo->ndo_packet_number = 1;
+			break;
+
+		case OPTION_VERSION:
+			print_version(stdout);
+			exit_tcpdump(S_SUCCESS);
+			break;
+
+#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
+		case OPTION_TSTAMP_PRECISION:
+			ndo->ndo_tstamp_precision = tstamp_precision_from_string(optarg);
+			if (ndo->ndo_tstamp_precision < 0)
+				error("unsupported time stamp precision");
+			break;
+#endif
+
+#ifdef HAVE_PCAP_SET_IMMEDIATE_MODE
+		case OPTION_IMMEDIATE_MODE:
+			immediate_mode = 1;
+			break;
+#endif
+
+		case OPTION_PRINT:
+			print = 1;
+			break;
+
+#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
+		case OPTION_TSTAMP_MICRO:
+			ndo->ndo_tstamp_precision = PCAP_TSTAMP_PRECISION_MICRO;
+			break;
+
+		case OPTION_TSTAMP_NANO:
+			ndo->ndo_tstamp_precision = PCAP_TSTAMP_PRECISION_NANO;
+			break;
+#endif
+
+		case OPTION_FP_TYPE:
+			/*
+			 * Print out the type of floating-point arithmetic
+			 * we're doing; it's probably IEEE, unless somebody
+			 * tries to run this on a VAX, but the precision
+			 * may differ (e.g., it might be 32-bit, 64-bit,
+			 * or 80-bit).
+			 */
+			float_type_check(0x4e93312d);
+			return 0;
+
+		case OPTION_COUNT:
+			count_mode = 1;
+			break;
+
+		default:
+			print_usage(stderr);
+			exit_tcpdump(S_ERR_HOST_PROGRAM);
+			/* NOTREACHED */
+		}
+
+#ifdef HAVE_PCAP_FINDALLDEVS
+	if (Dflag)
+		show_devices_and_exit();
+#endif
+#ifdef HAVE_PCAP_FINDALLDEVS_EX
+	if (remote_interfaces_source != NULL)
+		show_remote_devices_and_exit();
+#endif
+
+#if defined(DLT_LINUX_SLL2) && defined(HAVE_PCAP_SET_DATALINK)
+/* Set default linktype DLT_LINUX_SLL2 when capturing on the "any" device */
+		if (device != NULL &&
+		    strncmp (device, "any", strlen("any")) == 0
+		    && yflag_dlt == -1)
+			yflag_dlt = DLT_LINUX_SLL2;
+#endif
+
+	switch (ndo->ndo_tflag) {
+
+	case 0: /* Default */
+	case 1: /* No time stamp */
+	case 2: /* Unix timeval style */
+	case 3: /* Microseconds/nanoseconds since previous packet */
+	case 4: /* Date + Default */
+	case 5: /* Microseconds/nanoseconds since first packet */
+		break;
+
+	default: /* Not supported */
+		error("only -t, -tt, -ttt, -tttt and -ttttt are supported");
+		break;
+	}
+
+	if (ndo->ndo_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.");
+
+	/*
+	 * If we're printing dissected packets to the standard output,
+	 * and either the standard output is a terminal or we're doing
+	 * "line" buffering, set the capture timeout to .1 second rather
+	 * than 1 second, as the user's probably expecting to see packets
+	 * pop up immediately shortly after they arrive.
+	 *
+	 * XXX - would there be some value appropriate for all cases,
+	 * based on, say, the buffer size and packet input rate?
+	 */
+	if ((WFileName == NULL || print) && (isatty(1) || lflag))
+		timeout = 100;
+
+#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", pcap_strerror(errno));
+
+			ret = get_next_file(VFile, VFileLine);
+			if (!ret)
+				error("Nothing in %s\n", VFileName);
+			RFileName = VFileLine;
+		}
+
+#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
+		pd = pcap_open_offline_with_tstamp_precision(RFileName,
+		    ndo->ndo_tstamp_precision, ebuf);
+#else
+		pd = pcap_open_offline(RFileName, ebuf);
+#endif
+
+		if (pd == NULL)
+			error("%s", ebuf);
+#ifdef HAVE_CAPSICUM
+		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);
+		fprintf(stderr, "reading from file %s", RFileName);
+		if (dlt_name == NULL) {
+			fprintf(stderr, ", link-type %u", dlt);
+		} else {
+			fprintf(stderr, ", link-type %s (%s)", dlt_name,
+				pcap_datalink_val_to_description(dlt));
+		}
+		fprintf(stderr, ", snapshot length %d\n", pcap_snapshot(pd));
+#ifdef DLT_LINUX_SLL2
+		if (dlt == DLT_LINUX_SLL2)
+			fprintf(stderr, "Warning: interface names might be incorrect\n");
+#endif
+	} else if (dflag && !device) {
+		int dump_dlt = DLT_EN10MB;
+		/*
+		 * We're dumping the compiled code without an explicit
+		 * device specification.  (If a device is specified, we
+		 * definitely want to open it to use the DLT of that device.)
+		 * Either default to DLT_EN10MB with a warning, or use
+		 * the user-specified value if supplied.
+		 */
+		/*
+		 * If no snapshot length was specified, or a length of 0 was
+		 * specified, default to 256KB.
+		 */
+		if (ndo->ndo_snaplen == 0)
+			ndo->ndo_snaplen = MAXIMUM_SNAPLEN;
+		/*
+		 * If a DLT was specified with the -y flag, use that instead.
+		 */
+		if (yflag_dlt != -1)
+			dump_dlt = yflag_dlt;
+		else
+			fprintf(stderr, "Warning: assuming Ethernet\n");
+	        pd = pcap_open_dead(dump_dlt, ndo->ndo_snaplen);
+	} else {
+		/*
+		 * We're doing a live capture.
+		 */
+		if (device == NULL) {
+			/*
+			 * No interface was specified.  Pick one.
+			 */
+#ifdef HAVE_PCAP_FINDALLDEVS
+			/*
+			 * Find the list of interfaces, and pick
+			 * the first interface.
+			 */
+			if (pcap_findalldevs(&devlist, ebuf) == -1)
+				error("%s", ebuf);
+			if (devlist == NULL)
+				error("no interfaces available for capture");
+			device = strdup(devlist->name);
+			pcap_freealldevs(devlist);
+#else /* HAVE_PCAP_FINDALLDEVS */
+			/*
+			 * Use whatever interface pcap_lookupdev()
+			 * chooses.
+			 */
+			device = pcap_lookupdev(ebuf);
+			if (device == NULL)
+				error("%s", ebuf);
+#endif
+		}
+
+		/*
+		 * Try to open the interface with the specified name.
+		 */
+		pd = open_interface(device, ndo, ebuf);
+		if (pd == NULL) {
+			/*
+			 * That failed.  If we can get a list of
+			 * interfaces, and the interface name
+			 * is purely numeric, try to use it as
+			 * a 1-based index in the list of
+			 * interfaces.
+			 */
+#ifdef HAVE_PCAP_FINDALLDEVS
+			devnum = parse_interface_number(device);
+			if (devnum == -1) {
+				/*
+				 * It's not a number; just report
+				 * the open error and fail.
+				 */
+				error("%s", ebuf);
+			}
+
+			/*
+			 * OK, it's a number; try to find the
+			 * interface with that index, and try
+			 * to open it.
+			 *
+			 * find_interface_by_number() exits if it
+			 * couldn't be found.
+			 */
+			device = find_interface_by_number(device, devnum);
+			pd = open_interface(device, ndo, ebuf);
+			if (pd == NULL)
+				error("%s", ebuf);
+#else /* HAVE_PCAP_FINDALLDEVS */
+			/*
+			 * We can't get a list of interfaces; just
+			 * fail.
+			 */
+			error("%s", ebuf);
+#endif /* HAVE_PCAP_FINDALLDEVS */
+		}
+
+		/*
+		 * Let user own process after capture device 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(pd, device);
+		if (yflag_dlt >= 0) {
+#ifdef HAVE_PCAP_SET_DATALINK
+			if (pcap_set_datalink(pd, yflag_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 (yflag_dlt != pcap_datalink(pd)) {
+				error("%s is not one of the DLTs supported by this device\n",
+				      yflag_dlt_name);
+			}
+#endif
+			(void)fprintf(stderr, "%s: data link type %s\n",
+				      program_name,
+				      pcap_datalink_val_to_name(yflag_dlt));
+			(void)fflush(stderr);
+		}
+		i = pcap_snapshot(pd);
+		if (ndo->ndo_snaplen < i) {
+			if (ndo->ndo_snaplen != 0)
+				warning("snaplen raised from %d to %d", ndo->ndo_snaplen, i);
+			ndo->ndo_snaplen = i;
+		} else if (ndo->ndo_snaplen > i) {
+			warning("snaplen lowered from %d to %d", ndo->ndo_snaplen, i);
+			ndo->ndo_snaplen = i;
+		}
+                if(ndo->ndo_fflag != 0) {
+                        if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {
+                                warning("foreign (-f) flag used but: %s", ebuf);
+                        }
+                }
+
+	}
+	if (infile)
+		cmdbuf = read_infile(infile);
+	else
+		cmdbuf = copy_argv(&argv[optind]);
+
+#ifdef HAVE_PCAP_SET_OPTIMIZER_DEBUG
+	pcap_set_optimizer_debug(dflag);
+#endif
+	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);
+		pcap_freecode(&fcode);
+		exit_tcpdump(S_SUCCESS);
+	}
+
+#ifdef HAVE_CASPER
+	if (!ndo->ndo_nflag)
+		capdns = capdns_setup();
+#endif	/* HAVE_CASPER */
+
+	init_print(ndo, localnet, netmask);
+
+#ifndef _WIN32
+	(void)setsignal(SIGPIPE, cleanup);
+	(void)setsignal(SIGTERM, cleanup);
+#endif /* _WIN32 */
+	(void)setsignal(SIGINT, cleanup);
+#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.
+	 */
+
+	if (getuid() == 0 || geteuid() == 0) {
+#ifdef HAVE_LIBCAP_NG
+		/* Initialize capng */
+		capng_clear(CAPNG_SELECT_BOTH);
+		if (username) {
+DIAG_OFF_ASSIGN_ENUM
+			capng_updatev(
+				CAPNG_ADD,
+				CAPNG_PERMITTED | CAPNG_EFFECTIVE,
+				CAP_SETUID,
+				CAP_SETGID,
+				-1);
+DIAG_ON_ASSIGN_ENUM
+		}
+		if (chroot_dir) {
+DIAG_OFF_ASSIGN_ENUM
+			capng_update(
+				CAPNG_ADD,
+				CAPNG_PERMITTED | CAPNG_EFFECTIVE,
+				CAP_SYS_CHROOT
+				);
+DIAG_ON_ASSIGN_ENUM
+		}
+
+		if (WFileName) {
+DIAG_OFF_ASSIGN_ENUM
+			capng_update(
+				CAPNG_ADD,
+				CAPNG_PERMITTED | CAPNG_EFFECTIVE,
+				CAP_DAC_OVERRIDE
+				);
+DIAG_ON_ASSIGN_ENUM
+		}
+		capng_apply(CAPNG_SELECT_BOTH);
+#endif /* HAVE_LIBCAP_NG */
+		if (username || chroot_dir)
+			droproot(username, chroot_dir);
+
+	}
+#endif /* _WIN32 */
+
+	if (pcap_setfilter(pd, &fcode) < 0)
+		error("%s", pcap_geterr(pd));
+#ifdef HAVE_CAPSICUM
+	if (RFileName == NULL && VFileName == NULL && pcap_fileno(pd) != -1) {
+		static const unsigned long cmds[] = { BIOCGSTATS, BIOCROTZBUF };
+
+		/*
+		 * The various libpcap devices use a combination of
+		 * read (bpf), ioctl (bpf, netmap), poll (netmap)
+		 * so we add the relevant access rights.
+		 */
+		cap_rights_init(&rights, CAP_IOCTL, CAP_READ, CAP_EVENT);
+		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) {
+		/* 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);
+
+		pdd = pcap_dump_open(pd, dumpinfo.CurrentFileName);
+#ifdef HAVE_LIBCAP_NG
+		/* Give up CAP_DAC_OVERRIDE capability.
+		 * Only allow it to be restored if the -C or -G flag have been
+		 * set since we may need to create more files later on.
+		 */
+		capng_update(
+			CAPNG_DROP,
+			(Cflag || Gflag ? 0 : CAPNG_PERMITTED)
+				| CAPNG_EFFECTIVE,
+			CAP_DAC_OVERRIDE
+			);
+		capng_apply(CAPNG_SELECT_BOTH);
+#endif /* HAVE_LIBCAP_NG */
+		if (pdd == NULL)
+			error("%s", pcap_geterr(pd));
+#ifdef HAVE_CAPSICUM
+		set_dumper_capsicum_rights(pdd);
+#endif
+		if (Cflag != 0 || Gflag != 0) {
+#ifdef HAVE_CAPSICUM
+			/*
+			 * basename() and dirname() may modify their input buffer
+			 * and they do since FreeBSD 12.0, but they didn't before.
+			 * Hence use the return value only, but always assume the
+			 * input buffer has been modified and would need to be
+			 * reset before the next use.
+			 */
+			char *WFileName_copy;
+
+			if ((WFileName_copy = strdup(WFileName)) == NULL) {
+				error("Unable to allocate memory for file %s",
+				    WFileName);
+			}
+			DIAG_OFF_C11_EXTENSIONS
+			dumpinfo.WFileName = strdup(basename(WFileName_copy));
+			DIAG_ON_C11_EXTENSIONS
+			if (dumpinfo.WFileName == NULL) {
+				error("Unable to allocate memory for file %s",
+				    WFileName);
+			}
+			free(WFileName_copy);
+
+			if ((WFileName_copy = strdup(WFileName)) == NULL) {
+				error("Unable to allocate memory for file %s",
+				    WFileName);
+			}
+			DIAG_OFF_C11_EXTENSIONS
+			char *WFileName_dirname = dirname(WFileName_copy);
+			DIAG_ON_C11_EXTENSIONS
+			dumpinfo.dirfd = open(WFileName_dirname,
+			    O_DIRECTORY | O_RDONLY);
+			if (dumpinfo.dirfd < 0) {
+				error("unable to open directory %s",
+				    WFileName_dirname);
+			}
+			free(WFileName_dirname);
+			free(WFileName_copy);
+
+			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");
+			}
+			if (cap_fcntls_limit(dumpinfo.dirfd, CAP_FCNTL_GETFL) < 0 &&
+			    errno != ENOSYS) {
+				error("unable to limit dump descriptor fcntls");
+			}
+#else	/* !HAVE_CAPSICUM */
+			dumpinfo.WFileName = WFileName;
+#endif
+			callback = dump_packet_and_trunc;
+			dumpinfo.pd = pd;
+			dumpinfo.pdd = pdd;
+			pcap_userdata = (u_char *)&dumpinfo;
+		} else {
+			callback = dump_packet;
+			dumpinfo.WFileName = WFileName;
+			dumpinfo.pd = pd;
+			dumpinfo.pdd = pdd;
+			pcap_userdata = (u_char *)&dumpinfo;
+		}
+		if (print) {
+			dlt = pcap_datalink(pd);
+			ndo->ndo_if_printer = get_if_printer(dlt);
+			dumpinfo.ndo = ndo;
+		} else
+			dumpinfo.ndo = NULL;
+
+#ifdef HAVE_PCAP_DUMP_FLUSH
+		if (Uflag)
+			pcap_dump_flush(pdd);
+#endif
+	} else {
+		dlt = pcap_datalink(pd);
+		ndo->ndo_if_printer = get_if_printer(dlt);
+		callback = print_packet;
+		pcap_userdata = (u_char *)ndo;
+	}
+
+#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
+#ifdef SIGNAL_FLUSH_PCAP
+	(void)setsignal(SIGNAL_FLUSH_PCAP, flushpcap);
+#endif
+
+	if (ndo->ndo_vflag > 0 && WFileName && RFileName == NULL && !print) {
+		/*
+		 * When capturing to a file, if "--print" wasn't specified,
+		 *"-v" means tcpdump should, once per second,
+		 * "v"erbosely report the number of packets captured.
+		 * Except when reading from a file, because -r, -w and -v
+		 * together used to make a corner case, in which pcap_loop()
+		 * errored due to EINTR (see GH #155 for details).
+		 */
+#ifdef _WIN32
+		/*
+		 * https://blogs.msdn.microsoft.com/oldnewthing/20151230-00/?p=92741
+		 *
+		 * suggests that this dates back to W2K.
+		 *
+		 * I don't know what a "long wait" is, but we'll assume
+		 * that printing the stats could be a "long wait".
+		 */
+		CreateTimerQueueTimer(&timer_handle, NULL,
+		    verbose_stats_dump, NULL, 1000, 1000,
+		    WT_EXECUTEDEFAULT|WT_EXECUTELONGFUNCTION);
+		setvbuf(stderr, NULL, _IONBF, 0);
+#else /* _WIN32 */
+		/*
+		 * Assume this is UN*X, and that it has setitimer(); that
+		 * dates back to UNIX 95.
+		 */
+		struct itimerval timer;
+		(void)setsignal(SIGALRM, verbose_stats_dump);
+		timer.it_interval.tv_sec = 1;
+		timer.it_interval.tv_usec = 0;
+		timer.it_value.tv_sec = 1;
+		timer.it_value.tv_usec = 1;
+		setitimer(ITIMER_REAL, &timer, NULL);
+#endif /* _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 (!ndo->ndo_vflag && !WFileName) {
+			(void)fprintf(stderr,
+			    "%s: verbose output suppressed, use -v[v]... 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);
+		(void)fprintf(stderr, "listening on %s", device);
+		if (dlt_name == NULL) {
+			(void)fprintf(stderr, ", link-type %u", dlt);
+		} else {
+			(void)fprintf(stderr, ", link-type %s (%s)", dlt_name,
+				      pcap_datalink_val_to_description(dlt));
+		}
+		(void)fprintf(stderr, ", snapshot length %d bytes\n", ndo->ndo_snaplen);
+		(void)fflush(stderr);
+	}
+
+#ifdef HAVE_CAPSICUM
+	cansandbox = (VFileName == NULL && zflag == NULL);
+#ifdef HAVE_CASPER
+	cansandbox = (cansandbox && (ndo->ndo_nflag || capdns != NULL));
+#else
+	cansandbox = (cansandbox && ndo->ndo_nflag);
+#endif /* HAVE_CASPER */
+	if (cansandbox && cap_enter() < 0 && errno != ENOSYS)
+		error("unable to enter the capability mode");
+#endif	/* HAVE_CAPSICUM */
+
+	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 == -2) {
+			/*
+			 * We got interrupted. If we are reading multiple
+			 * files (via -V) set these so that we stop.
+			 */
+			VFileName = NULL;
+			ret = NULL;
+		}
+		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) {
+				int new_dlt;
+
+				RFileName = VFileLine;
+				pd = pcap_open_offline(RFileName, ebuf);
+				if (pd == NULL)
+					error("%s", ebuf);
+#ifdef HAVE_CAPSICUM
+				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 (new_dlt != dlt) {
+					/*
+					 * The new file has a different
+					 * link-layer header type from the
+					 * previous one.
+					 */
+					if (WFileName != NULL) {
+						/*
+						 * We're writing raw packets
+						 * that match the filter to
+						 * a pcap file.  pcap files
+						 * don't support multiple
+						 * different link-layer
+						 * header types, so we fail
+						 * here.
+						 */
+						error("%s: new dlt does not match original", RFileName);
+					}
+
+					/*
+					 * We're printing the decoded packets;
+					 * switch to the new DLT.
+					 *
+					 * To do that, we need to change
+					 * the printer, change the DLT name,
+					 * and recompile the filter with
+					 * the new DLT.
+					 */
+					dlt = new_dlt;
+					ndo->ndo_if_printer = get_if_printer(dlt);
+					if (pcap_compile(pd, &fcode, cmdbuf, Oflag, netmask) < 0)
+						error("%s", pcap_geterr(pd));
+				}
+
+				/*
+				 * Set the filter on the new file.
+				 */
+				if (pcap_setfilter(pd, &fcode) < 0)
+					error("%s", pcap_geterr(pd));
+
+				/*
+				 * Report the new file.
+				 */
+				dlt_name = pcap_datalink_val_to_name(dlt);
+				fprintf(stderr, "reading from file %s", RFileName);
+				if (dlt_name == NULL) {
+					fprintf(stderr, ", link-type %u", dlt);
+				} else {
+					fprintf(stderr, ", link-type %s (%s)",
+						dlt_name,
+						pcap_datalink_val_to_description(dlt));
+				}
+				fprintf(stderr, ", snapshot length %d\n", pcap_snapshot(pd));
+			}
+		}
+	}
+	while (ret != NULL);
+
+	if (count_mode && RFileName != NULL)
+		fprintf(stdout, "%u packet%s\n", packets_captured,
+			PLURAL_SUFFIX(packets_captured));
+
+	free(cmdbuf);
+	pcap_freecode(&fcode);
+	exit_tcpdump(status == -1 ? S_ERR_HOST_PROGRAM : S_SUCCESS);
+}
+
+/*
+ * Catch a signal.
+ */
+static void
+(*setsignal (int sig, void (*func)(int)))(int)
+{
+#ifdef _WIN32
+	return (signal(sig, func));
+#else
+	struct sigaction old, new;
+
+	memset(&new, 0, sizeof(new));
+	new.sa_handler = func;
+	if ((sig == SIGCHLD)
+# ifdef SIGNAL_REQ_INFO
+		|| (sig == SIGNAL_REQ_INFO)
+# endif
+# ifdef SIGNAL_FLUSH_PCAP
+		|| (sig == SIGNAL_FLUSH_PCAP)
+# endif
+		)
+		new.sa_flags = SA_RESTART;
+	if (sigaction(sig, &new, &old) < 0)
+		return (SIG_ERR);
+	return (old.sa_handler);
+#endif
+}
+
+/* make a clean exit on interrupts */
+static void
+cleanup(int signo _U_)
+{
+#ifdef _WIN32
+	if (timer_handle != INVALID_HANDLE_VALUE) {
+		DeleteTimerQueueTimer(NULL, timer_handle, NULL);
+		CloseHandle(timer_handle);
+		timer_handle = INVALID_HANDLE_VALUE;
+        }
+#else /* _WIN32 */
+	struct itimerval timer;
+
+	timer.it_interval.tv_sec = 0;
+	timer.it_interval.tv_usec = 0;
+	timer.it_value.tv_sec = 0;
+	timer.it_value.tv_usec = 0;
+	setitimer(ITIMER_REAL, &timer, NULL);
+#endif /* _WIN32 */
+
+#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_tcpdump(S_SUCCESS);
+#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 void
+child_cleanup(int signo _U_)
+{
+  wait(NULL);
+}
+#endif /* HAVE_FORK && HAVE_VFORK */
+
+static void
+info(int verbose)
+{
+	struct pcap_stat stats;
+
+	/*
+	 * Older versions of libpcap didn't set ps_ifdrop on some
+	 * platforms; initialize it to 0 to handle that.
+	 */
+	stats.ps_ifdrop = 0;
+	if (pcap_stats(pd, &stats) < 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", stats.ps_recv,
+	    PLURAL_SUFFIX(stats.ps_recv));
+	if (!verbose)
+		fputs(", ", stderr);
+	else
+		putc('\n', stderr);
+	(void)fprintf(stderr, "%u packet%s dropped by kernel", stats.ps_drop,
+	    PLURAL_SUFFIX(stats.ps_drop));
+	if (stats.ps_ifdrop != 0) {
+		if (!verbose)
+			fputs(", ", stderr);
+		else
+			putc('\n', stderr);
+		(void)fprintf(stderr, "%u packet%s dropped by interface\n",
+		    stats.ps_ifdrop, PLURAL_SUFFIX(stats.ps_ifdrop));
+	} else
+		putc('\n', stderr);
+	infoprint = 0;
+}
+
+#if defined(HAVE_FORK) || defined(HAVE_VFORK)
+#ifdef HAVE_FORK
+#define fork_subprocess() fork()
+#else
+#define fork_subprocess() vfork()
+#endif
+static void
+compress_savefile(const char *filename)
+{
+	pid_t child;
+
+	child = fork_subprocess();
+	if (child == -1) {
+		fprintf(stderr,
+			"compress_savefile: fork failed: %s\n",
+			pcap_strerror(errno));
+		return;
+	}
+	if (child != 0) {
+		/* Parent process. */
+		return;
+	}
+
+	/*
+	 * Child process.
+	 * 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) failed: %s\n",
+			zflag,
+			filename,
+			pcap_strerror(errno));
+#ifdef HAVE_FORK
+	exit(S_ERR_HOST_PROGRAM);
+#else
+	_exit(S_ERR_HOST_PROGRAM);
+#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;
+
+	++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("%s: can't get current_time: %s",
+			    __func__, pcap_strerror(errno));
+		}
+
+
+		/* If the time is greater than the specified window, rotate */
+		if (t - Gflag_time >= Gflag) {
+#ifdef HAVE_CAPSICUM
+			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->pdd);
+
+			/*
+			 * 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);
+				info(1);
+				exit_tcpdump(S_SUCCESS);
+				/* 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");
+			/*
+			 * Gflag was set otherwise we wouldn't be here. Reset the count
+			 * so multiple files would end with 1,2,3 in the filename.
+			 * The counting is handled with the -C flow after this.
+			 */
+			Cflag_count = 0;
+
+			/*
+			 * 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_LIBCAP_NG
+			capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
+			capng_apply(CAPNG_SELECT_BOTH);
+#endif /* HAVE_LIBCAP_NG */
+#ifdef HAVE_CAPSICUM
+			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->pdd = pcap_dump_fopen(dump_info->pd, fp);
+#else	/* !HAVE_CAPSICUM */
+			dump_info->pdd = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
+#endif
+#ifdef HAVE_LIBCAP_NG
+			capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
+			capng_apply(CAPNG_SELECT_BOTH);
+#endif /* HAVE_LIBCAP_NG */
+			if (dump_info->pdd == NULL)
+				error("%s", pcap_geterr(pd));
+#ifdef HAVE_CAPSICUM
+			set_dumper_capsicum_rights(dump_info->pdd);
+#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) {
+#ifdef HAVE_PCAP_DUMP_FTELL64
+		int64_t size = pcap_dump_ftell64(dump_info->pdd);
+#else
+		/*
+		 * XXX - this only handles a Cflag value > 2^31-1 on
+		 * LP64 platforms; to handle ILP32 (32-bit UN*X and
+		 * Windows) or LLP64 (64-bit Windows) would require
+		 * a version of libpcap with pcap_dump_ftell64().
+		 */
+		long size = pcap_dump_ftell(dump_info->pdd);
+#endif
+
+		if (size == -1)
+			error("ftell fails on output file");
+		if (size > Cflag) {
+#ifdef HAVE_CAPSICUM
+			FILE *fp;
+			int fd;
+#endif
+
+			/*
+			 * Close the current file and open a new one.
+			 */
+			pcap_dump_close(dump_info->pdd);
+
+			/*
+			 * 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("%s: malloc", __func__);
+			MakeFilename(dump_info->CurrentFileName, dump_info->WFileName, Cflag_count, WflagChars);
+#ifdef HAVE_LIBCAP_NG
+			capng_update(CAPNG_ADD, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
+			capng_apply(CAPNG_SELECT_BOTH);
+#endif /* HAVE_LIBCAP_NG */
+#ifdef HAVE_CAPSICUM
+			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->pdd = pcap_dump_fopen(dump_info->pd, fp);
+#else	/* !HAVE_CAPSICUM */
+			dump_info->pdd = pcap_dump_open(dump_info->pd, dump_info->CurrentFileName);
+#endif
+#ifdef HAVE_LIBCAP_NG
+			capng_update(CAPNG_DROP, CAPNG_EFFECTIVE, CAP_DAC_OVERRIDE);
+			capng_apply(CAPNG_SELECT_BOTH);
+#endif /* HAVE_LIBCAP_NG */
+			if (dump_info->pdd == NULL)
+				error("%s", pcap_geterr(pd));
+#ifdef HAVE_CAPSICUM
+			set_dumper_capsicum_rights(dump_info->pdd);
+#endif
+		}
+	}
+
+	pcap_dump((u_char *)dump_info->pdd, h, sp);
+#ifdef HAVE_PCAP_DUMP_FLUSH
+	if (Uflag)
+		pcap_dump_flush(dump_info->pdd);
+#endif
+
+	if (dump_info->ndo != NULL)
+		pretty_print_packet(dump_info->ndo, h, sp, packets_captured);
+
+	--infodelay;
+	if (infoprint)
+		info(0);
+}
+
+static void
+dump_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
+{
+	struct dump_info *dump_info;
+
+	++packets_captured;
+
+	++infodelay;
+
+	dump_info = (struct dump_info *)user;
+
+	pcap_dump((u_char *)dump_info->pdd, h, sp);
+#ifdef HAVE_PCAP_DUMP_FLUSH
+	if (Uflag)
+		pcap_dump_flush(dump_info->pdd);
+#endif
+
+	if (dump_info->ndo != NULL)
+		pretty_print_packet(dump_info->ndo, h, sp, packets_captured);
+
+	--infodelay;
+	if (infoprint)
+		info(0);
+}
+
+static void
+print_packet(u_char *user, const struct pcap_pkthdr *h, const u_char *sp)
+{
+	++packets_captured;
+
+	++infodelay;
+
+	if (!count_mode)
+		pretty_print_packet((netdissect_options *)user, h, sp, packets_captured);
+
+	--infodelay;
+	if (infoprint)
+		info(0);
+}
+
+#ifdef SIGNAL_REQ_INFO
+static void
+requestinfo(int signo _U_)
+{
+	if (infodelay)
+		++infoprint;
+	else
+		info(0);
+}
+#endif
+
+#ifdef SIGNAL_FLUSH_PCAP
+static void
+flushpcap(int signo _U_)
+{
+	if (pdd != NULL)
+		pcap_dump_flush(pdd);
+}
+#endif
+
+static void
+print_packets_captured (void)
+{
+	static u_int prev_packets_captured, first = 1;
+
+	if (infodelay == 0 && (first || packets_captured != prev_packets_captured)) {
+		fprintf(stderr, "Got %u\r", packets_captured);
+		first = 0;
+		prev_packets_captured = packets_captured;
+	}
+}
+
+/*
+ * Called once each second in verbose mode while dumping to file
+ */
+#ifdef _WIN32
+static void CALLBACK verbose_stats_dump(PVOID param _U_,
+    BOOLEAN timer_fired _U_)
+{
+	print_packets_captured();
+}
+#else /* _WIN32 */
+static void verbose_stats_dump(int sig _U_)
+{
+	print_packets_captured();
+}
+#endif /* _WIN32 */
+
+DIAG_OFF_DEPRECATION
+static void
+print_version(FILE *f)
+{
+#ifndef HAVE_PCAP_LIB_VERSION
+  #ifdef HAVE_PCAP_VERSION
+	extern char pcap_version[];
+  #else /* HAVE_PCAP_VERSION */
+	static char pcap_version[] = "unknown";
+  #endif /* HAVE_PCAP_VERSION */
+#endif /* HAVE_PCAP_LIB_VERSION */
+	const char *smi_version_string;
+
+	(void)fprintf(f, "%s version " PACKAGE_VERSION "\n", program_name);
+#ifdef HAVE_PCAP_LIB_VERSION
+	(void)fprintf(f, "%s\n", pcap_lib_version());
+#else /* HAVE_PCAP_LIB_VERSION */
+	(void)fprintf(f, "libpcap version %s\n", pcap_version);
+#endif /* HAVE_PCAP_LIB_VERSION */
+
+#if defined(HAVE_LIBCRYPTO) && defined(SSLEAY_VERSION)
+	(void)fprintf (f, "%s\n", SSLeay_version(SSLEAY_VERSION));
+#endif
+
+	smi_version_string = nd_smi_version_string();
+	if (smi_version_string != NULL)
+		(void)fprintf (f, "SMI-library: %s\n", smi_version_string);
+
+#if defined(__SANITIZE_ADDRESS__)
+	(void)fprintf (f, "Compiled with AddressSanitizer/GCC.\n");
+#elif defined(__has_feature)
+#  if __has_feature(address_sanitizer)
+	(void)fprintf (f, "Compiled with AddressSanitizer/Clang.\n");
+#  elif __has_feature(memory_sanitizer)
+	(void)fprintf (f, "Compiled with MemorySanitizer/Clang.\n");
+#  endif
+#endif /* __SANITIZE_ADDRESS__ or __has_feature */
+}
+DIAG_ON_DEPRECATION
+
+static void
+print_usage(FILE *f)
+{
+	print_version(f);
+	(void)fprintf(f,
+"Usage: %s [-Abd" D_FLAG "efhH" I_FLAG J_FLAG "KlLnNOpqStu" U_FLAG "vxX#]" B_FLAG_USAGE " [ -c count ] [--count]\n", program_name);
+	(void)fprintf(f,
+"\t\t[ -C file_size ] [ -E algo:secret ] [ -F file ] [ -G seconds ]\n");
+	(void)fprintf(f,
+"\t\t[ -i interface ]" IMMEDIATE_MODE_USAGE j_FLAG_USAGE "\n");
+#ifdef HAVE_PCAP_FINDALLDEVS_EX
+	(void)fprintf(f,
+"\t\t" LIST_REMOTE_INTERFACES_USAGE "\n");
+#endif
+#ifdef USE_LIBSMI
+	(void)fprintf(f,
+"\t\t" m_FLAG_USAGE "\n");
+#endif
+	(void)fprintf(f,
+"\t\t[ -M secret ] [ --number ] [ --print ]" Q_FLAG_USAGE "\n");
+	(void)fprintf(f,
+"\t\t[ -r file ] [ -s snaplen ] [ -T type ] [ --version ]\n");
+	(void)fprintf(f,
+"\t\t[ -V file ] [ -w file ] [ -W filecount ] [ -y datalinktype ]\n");
+#ifdef HAVE_PCAP_SET_TSTAMP_PRECISION
+	(void)fprintf(f,
+"\t\t[ --time-stamp-precision precision ] [ --micro ] [ --nano ]\n");
+#endif
+	(void)fprintf(f,
+"\t\t[ -z postrotate-command ] [ -Z user ] [ expression ]\n");
+}