des.h

这个是数据加密标准的VC算法

/* des.h -
 *	Headers and defines for des.c
 */

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

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.
 */

extern void cpkey(unsigned long *);
/*		   cookedkey[32]
 * Copies the contents of the internal key register into the storage
 * located at &cookedkey[0].
 */

extern void des(unsigned char *, unsigned char *);
/*		    from[8]	      to[8]
 * Encrypts/Decrypts (according to the key currently loaded in the
 * internal key register) one block of eight bytes at address 'from'
 * into the block at address 'to'.  They can be the same.
 */
extern void chaos_key(unsigned char *,double *);
extern void des_key(des_ctx *, unsigned char *);