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/*--------------------------------------------------------------------------------
DES.C: DES Algorithm Program from the Book Appliced Cryptography, Bruce Schneier
--------------------------------------------------------------------------------*/

#define EN0 0 /* MODE == encrypt */
#define DE1 1 /* MODE == decrypt */

#include <stdio.h>
#include <reg51.h>

typedef struct {
unsigned long ek[32];
unsigned long dk[32];
} des_ctx;

extern void deskey(unsigned char *, short);
/* hexkey[8] MODE
* Sets the internal key register according to the hexadecimal
* key contained in the 8 bytes of hexkey, according to the DES,
* for encryption or decryption according to MODE.
*/

extern void usekey(unsigned long *);
/* cookedkey[32]
* Loads the internal key register with the data in cookedkey.
*/

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