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/*
* $Source$
* $Author$
*
* Copyright 1988,1990 by the Massachusetts Institute of Technology.
* All Rights Reserved.
*
* Export of this software from the United States of America is assumed
* to require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*
*
* This routine generates an odd-parity table for use in key generation.
*/
#if !defined(lint) && !defined(SABER)
static char rcsid_make_odd_c[] =
"$Id$";
#endif /* !lint & !SABER */
#include <stdio.h>
void gen(stream)
FILE *stream;
{
/*
* map a byte into its equivalent with odd parity, where odd
* parity is in the least significant bit
*/
register i, j, k, odd;
fprintf(stream,
"static unsigned char const odd_parity[256] = {\n");
for (i = 0; i < 256; i++) {
odd = 0;
/* shift out the lsb parity bit */
k = i >> 1;
/* then count the other bits */
for (j = 0; j < 7; j++) {
odd ^= (k&1);
k = k >> 1;
}
k = i&~1;
if (!odd)
k |= 1;
fprintf(stream, "%3d", k);
if (i < 255)
fprintf(stream, ", ");
if (i%8 == 0)
fprintf(stream, "\n");
}
fprintf(stream, "};\n");
}
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