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/*
* des - fast & portable DES encryption & decryption.
* Copyright (C) 1992 Dana L. How
* Please see the file `README' for the complete copyright notice.
*
* Slightly edited by Niels Mller, 1997
*/
#include "des.h"
#include "RCSID.h"
RCSID2(desQuick_cRcs, "$Id$");
extern unsigned INT32 des_keymap[];
/* static information */
static int depth = 0; /* keep track of the request depth */
unsigned INT32 des_bigmap[0x4000]; /* big lookup table */
/* fill in the 64k table used by the `quick' option */
void
DesQuickInit(void)
{
int s1, s3, x;
unsigned INT32 * t0, * t1, * t2, * t3;
if ( depth++ )
return;
t0 = des_bigmap;
t1 = t0 + 64;
t2 = t1 + 64;
t3 = t2 + 64;
for ( s3 = 63; s3 >= 0; s3-- ) {
for ( s1 = 63; s1 >= 0; s1-- ) {
x = (s3 << 8) | s1;
t0[x] = des_keymap[s3+128] ^ des_keymap[s1+192];
t1[x] = des_keymap[s3 ] ^ des_keymap[s1+ 64];
t2[x] = des_keymap[s3+384] ^ des_keymap[s1+448];
t3[x] = des_keymap[s3+256] ^ des_keymap[s1+320];
}
}
}
/* free the 64k table, if necessary */
void
DesQuickDone(void)
{
}