/*-
 * Copyright (c) 2002 Millions Consulting Limited
 * 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.
 *
 * $Id: poker.c,v 1.1.1.1 2002/09/11 03:36:00 stacy Exp $
 */

#include <sys/types.h>

/*
 * FIPS 140-1 poker test for a random number generator
 *
 * Refrence:
 * http://csrc.nist.gov/publications/fips/fips140-1/fips1401.htm
 */

/* s should point to a stream of 20,000 bits of muck */
int fips_poker_test(u_char *s)
	{
	int f[16];
	int i;
	double X;

	for(i = 0; i < 16; i++)
		f[i] = 0;

	for(i = 0; i < 2500; i++, s++)
		{
		u_char v;
		v = *s & 0x0f;
		f[v]++;
		v = ((*s & 0xf0) >> 4);
		f[v]++;
		}

	X = 0.0;
	for(i = 0; i <16; i++)
		{
		X += (((double)f[i]) * ((double)f[i]));
		}
	X = (16.0 / 5000.0) * X - 5000.0;

	if(X > 1.03 && X < 57.4) return 1;
	else return 0;
	}