虎牌焖烧杯食谱做粥:用c实现des算法!!!

/* d3des.h -
*
* Headers and defines for d3des.c
* Graven Imagery, 1992.
*
* Copyright (c) 1988,1989,1990,1991,1992 by Richard Outerbridge
* (GEnie : OUTER; CIS : [71755,204])
*/

#define D2_DES /* include double-length support */
#define D3_DES /* include triple-length support */

#ifdef D3_DES
#ifndef D2_DES
#define D2_DES /* D2_DES is needed for D3_DES */
#endif
#endif

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

/* A useful alias on 68000-ish machines, but NOT USED HERE. */

typedef union {
unsigned long blok[2];
unsigned short word[4];
unsigned char byte[8];
} M68K;

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.
*/

#ifdef D2_DES

#define desDkey(a,b) des2key((a),(b))
extern void des2key(unsigned char *, short);
/* hexkey[16] MODE
* Sets the internal key registerS according to the hexadecimal
* keyS contained in the 16 bytes of hexkey, according to the DES,
* for DOUBLE encryption or decryption according to MODE.
* NOTE: this clobbers all three key registers!
*/

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

extern void D2des(unsigned char *, unsigned char *);
/* from[16] to[16]
* Encrypts/Decrypts (according to the keyS currently loaded in the
* internal key registerS) one block of SIXTEEN bytes at address 'from'
* into the block at address 'to'. They can be the same.
*/

extern void makekey(char *, unsigned char *);
/* *password, single-length key[8]
* With a double-length default key, this routine hashes a NULL-terminated
* string into an eight-byte random-looking key, suitable for use with the
* deskey() routine.
*/

#define makeDkey(a,b) make2key((a),(b))
extern void make2key(char *, unsigned char *);
/* *password, double-length key[16]
* With a double-length default key, this routine hashes a NULL-terminated
* string into a sixteen-byte random-looking key, suitable for use with the
* des2key() routine.
*/

#ifndef D3_DES /* D2_DES only */

#define useDkey(a) use2key((a))
#define cpDkey(a) cp2key((a))

extern void use2key(unsigned long *);
/* cookedkey[64]
* Loads the internal key registerS with the data in cookedkey.
* NOTE: this clobbers all three key registers!
*/

extern void cp2key(unsigned long *);
/* cookedkey[64]
* Copies the contents of the internal key registerS into the storage
* located at &cookedkey[0].
*/

#else /* D3_DES too */

#define useDkey(a) use3key((a))
#define cpDkey(a) cp3key((a))

extern void des3key(unsigned char *, short);
/* hexkey[24] MODE
* Sets the internal key registerS according to the hexadecimal
* keyS contained in the 24 bytes of hexkey, according to the DES,
* for DOUBLE encryption or decryption according to MODE.
*/

extern void use3key(unsigned long *);
/* cookedkey[96]
* Loads the 3 internal key registerS with the data in cookedkey.
*/

extern void cp3key(unsigned long *);
/* cookedkey[96]
* Copies the contents of the 3 internal key registerS into the storage
* located at &cookedkey[0].
*/

extern void make3key(char *, unsigned char *);
/* *password, triple-length key[24]
* With a triple-length default key, this routine hashes a NULL-terminated
* string into a twenty-four-byte random-looking key, suitable for use with
* the des3key() routine.
*/

#endif /* D3_DES */
#endif /* D2_DES */