/*

 *  $Id: libnet_prand.c,v 1.7 2004/01/28 19:45:00 mike Exp $

 *

 *  libnet

 *  libnet_prand.c - pseudo-random number generation

 *

 *  Copyright (c) 1998 - 2004 Mike D. Schiffman <mike@infonexus.com>

 *  All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 *

 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 *

 */

#if (HAVE_CONFIG_H)

#include "../include/config.h"

#endif

#if (!(_WIN32) || (__CYGWIN__)) 

#include "../include/libnet.h"

#else

#include "../include/win32/libnet.h"

#endif

int

libnet_seed_prand(libnet_t *l)

{

	#if !(__WIN32__)

    struct timeval seed;

	#endif

    if (l == NULL)

    { 

        return (-1);

    } 

	#if __WIN32__

    srand((unsigned)time(NULL));

	#else

    if (gettimeofday(&seed, NULL) == -1)

    {

        snprintf(l->err_buf, LIBNET_ERRBUF_SIZE,

                "%s(): cannot gettimeofday\n", __func__);

        return (-1);

    }

    /*

     *  More entropy then just seeding with time(2).

     */

    srandom((unsigned)(seed.tv_sec ^ seed.tv_usec));

	#endif

    return (1);

}

uint32_t

libnet_get_prand(int mod)

{

    uint32_t n;  /* 0 to 4,294,967,295 */

#ifndef _WIN32

    n = random();

#else

	HCRYPTPROV hProv = 0;

	CryptAcquireContext(&hProv, 

		0, 0, PROV_RSA_FULL, 

		CRYPT_VERIFYCONTEXT);

	CryptGenRandom(hProv, 

		sizeof(n), (BYTE*)&n);

	CryptReleaseContext(hProv, 0); 

#endif

    switch (mod)

    {

        case LIBNET_PR2:

            return (n % 0x2);           /* 0 - 1 */

        case LIBNET_PR8:

            return (n % 0xff);          /* 0 - 255 */

        case LIBNET_PR16:

            return (n % 0x7fff);        /* 0 - 32767 */

        case LIBNET_PRu16:

            return (n % 0xffff);        /* 0 - 65535 */

        case LIBNET_PR32:

            return (n % 0x7fffffff);    /* 0 - 2147483647 */

        case LIBNET_PRu32:

            return (n);                 /* 0 - 4294967295 */

    }

    return (0);                         /* NOTTREACHED */

}

/* EOF */