/*

 * 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.

 */

#include "varattrs.h"

#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 <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <stdarg.h>

#include <limits.h>

#ifdef _WIN32

  #include <winsock2.h>

  #include <windows.h>

  #define THREAD_HANDLE			HANDLE

  #define THREAD_FUNC_ARG_TYPE		LPVOID

  #define THREAD_FUNC_RETURN_TYPE	DWORD __stdcall

  #include "getopt.h"

#else

  #include <pthread.h>

  #include <signal.h>

  #include <unistd.h>

  #define THREAD_HANDLE			pthread_t

  #define THREAD_FUNC_ARG_TYPE		void *

  #define THREAD_FUNC_RETURN_TYPE	void *

#endif

#include <errno.h>

#include <sys/types.h>

#include <pcap.h>

#include "pcap/funcattrs.h"

#ifdef _WIN32

  #include "portability.h"

#endif

static char *program_name;

/* Forwards */

static void countme(u_char *, const struct pcap_pkthdr *, const u_char *);

static void PCAP_NORETURN usage(void);

static void PCAP_NORETURN error(const char *, ...) PCAP_PRINTFLIKE(1, 2);

static void warning(const char *, ...) PCAP_PRINTFLIKE(1, 2);

static char *copy_argv(char **);

static pcap_t *pd;

#ifdef _WIN32

/*

 * Generate a string for a Win32-specific error (i.e. an error generated when

 * calling a Win32 API).

 * For errors occurred during standard C calls, we still use pcap_strerror()

 */

#define ERRBUF_SIZE	1024

static const char *

win32_strerror(DWORD error)

{

  static char errbuf[ERRBUF_SIZE+1];

  size_t errlen;

  FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM, NULL, error, 0, errbuf,

                ERRBUF_SIZE, NULL);

  /*

   * "FormatMessage()" "helpfully" sticks CR/LF at the end of the

   * message.  Get rid of it.

   */

  errlen = strlen(errbuf);

  if (errlen >= 2) {

    errbuf[errlen - 1] = '\0';

    errbuf[errlen - 2] = '\0';

    errlen -= 2;

  }

  return errbuf;

}

#else

static void

catch_sigusr1(int sig _U_)

{

	printf("Got SIGUSR1\n");

}

#endif

static void

sleep_secs(int secs)

{

#ifdef _WIN32

	Sleep(secs*1000);

#else

	unsigned secs_remaining;

	if (secs <= 0)

		return;

	secs_remaining = secs;

	while (secs_remaining != 0)

		secs_remaining = sleep(secs_remaining);

#endif

}

static THREAD_FUNC_RETURN_TYPE

capture_thread_func(THREAD_FUNC_ARG_TYPE arg)

{

	char *device = arg;

	int packet_count;

	int status;

#ifndef _WIN32

	struct sigaction action;

	sigset_t mask;

#endif

#ifndef _WIN32

	sigemptyset(&mask);

	action.sa_handler = catch_sigusr1;

	action.sa_mask = mask;

	action.sa_flags = 0;

	if (sigaction(SIGUSR1, &action, NULL) == -1)

		error("Can't catch SIGUSR1: %s", strerror(errno));

#endif

	printf("Listening on %s\n", device);

	for (;;) {

		packet_count = 0;

		status = pcap_dispatch(pd, -1, countme,

		    (u_char *)&packet_count);

		if (status < 0)

			break;

		if (status != 0) {

			printf("%d packets seen, %d packets counted after pcap_dispatch returns\n",

			    status, packet_count);

		} else

			printf("No packets seen by pcap_dispatch\n");

	}

	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');

		printf("Loop got broken\n");

	}

	(void)fflush(stdout);

	if (status == -1) {

		/*

		 * Error.  Report it.

		 */

		(void)fprintf(stderr, "%s: pcap_loop: %s\n",

		    program_name, pcap_geterr(pd));

	}

	return 0;

}

int

main(int argc, char **argv)

{

	register int op;

	register char *cp, *cmdbuf, *device;

	int immediate = 0;

	pcap_if_t *devlist;

	bpf_u_int32 localnet, netmask;

	struct bpf_program fcode;

	char ebuf[PCAP_ERRBUF_SIZE];

	int status;

	THREAD_HANDLE capture_thread;

#ifndef _WIN32

	void *retval;

#endif

	device = NULL;

	if ((cp = strrchr(argv[0], '/')) != NULL)

		program_name = cp + 1;

	else

		program_name = argv[0];

	opterr = 0;

	while ((op = getopt(argc, argv, "i:")) != -1) {

		switch (op) {

		case 'i':

			device = optarg;

			break;

		default:

			usage();

			/* NOTREACHED */

		}

	}

	if (device == NULL) {

		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);

	}

	*ebuf = '\0';

	pd = pcap_create(device, ebuf);

	if (pd == NULL)

		error("%s", ebuf);

	status = pcap_set_snaplen(pd, 65535);

	if (status != 0)

		error("%s: pcap_set_snaplen failed: %s",

			    device, pcap_statustostr(status));

	if (immediate) {

		status = pcap_set_immediate_mode(pd, 1);

		if (status != 0)

			error("%s: pcap_set_immediate_mode failed: %s",

			    device, pcap_statustostr(status));

	}

	status = pcap_set_timeout(pd, 5*60*1000);

	if (status != 0)

		error("%s: pcap_set_timeout failed: %s",

		    device, pcap_statustostr(status));

	status = pcap_activate(pd);

	if (status < 0) {

		/*

		 * pcap_activate() failed.

		 */

		error("%s: %s\n(%s)", device,

		    pcap_statustostr(status), pcap_geterr(pd));

	} else if (status > 0) {

		/*

		 * pcap_activate() succeeded, but it's warning us

		 * of a problem it had.

		 */

		warning("%s: %s\n(%s)", device,

		    pcap_statustostr(status), pcap_geterr(pd));

	}

	if (pcap_lookupnet(device, &localnet, &netmask, ebuf) < 0) {

		localnet = 0;

		netmask = 0;

		warning("%s", ebuf);

	}

	cmdbuf = copy_argv(&argv[optind]);

	if (pcap_compile(pd, &fcode, cmdbuf, 1, netmask) < 0)

		error("%s", pcap_geterr(pd));

	if (pcap_setfilter(pd, &fcode) < 0)

		error("%s", pcap_geterr(pd));

#ifdef _WIN32

	capture_thread = CreateThread(NULL, 0, capture_thread_func, device,

	    0, NULL);

	if (capture_thread == NULL)

		error("Can't create capture thread: %s",

		    win32_strerror(GetLastError()));

#else

	status = pthread_create(&capture_thread, NULL, capture_thread_func,

	    device);

	if (status != 0)

		error("Can't create capture thread: %s", strerror(status));

#endif

	sleep_secs(60);

	pcap_breakloop(pd);

#ifdef _WIN32

	printf("Setting event\n");

	if (!SetEvent(pcap_getevent(pd)))

		error("Can't set event for pcap_t: %s",

		    win32_strerror(GetLastError()));

	if (WaitForSingleObject(capture_thread, INFINITE) == WAIT_FAILED)

		error("Wait for thread termination failed: %s",

		    win32_strerror(GetLastError()));

	CloseHandle(capture_thread);

#else

	printf("Sending SIGUSR1\n");

	status = pthread_kill(capture_thread, SIGUSR1);

	if (status != 0)

		warning("Can't interrupt capture thread: %s", strerror(status));

	status = pthread_join(capture_thread, &retval);

	if (status != 0)

		error("Wait for thread termination failed: %s",

		    strerror(status));

#endif

	pcap_close(pd);

	pcap_freecode(&fcode);

	exit(status == -1 ? 1 : 0);

}

static void

countme(u_char *user, const struct pcap_pkthdr *h _U_, const u_char *sp _U_)

{

	int *counterp = (int *)user;

	(*counterp)++;

}

static void

usage(void)

{

	(void)fprintf(stderr, "Usage: %s [ -m ] [ -i interface ] [ -t timeout] [expression]\n",

	    program_name);

	exit(1);

}

/* 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(1);

	/* 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);

	}

}

/*

 * Copy arg vector into a new buffer, concatenating arguments with spaces.

 */

static char *

copy_argv(register char **argv)

{

	register char **p;

	register u_int len = 0;

	char *buf;

	char *src, *dst;

	p = argv;

	if (*p == 0)

		return 0;

	while (*p)

		len += strlen(*p++) + 1;

	buf = (char *)malloc(len);

	if (buf == NULL)

		error("copy_argv: malloc");

	p = argv;

	dst = buf;

	while ((src = *p++) != NULL) {

		while ((*dst++ = *src++) != '\0')

			;

		dst[-1] = ' ';

	}

	dst[-1] = '\0';

	return buf;

}