des.h des.c 怎么用？

#ifndef _DES_H

#define _DES_H



#ifndef uint8

#define uint8  unsigned char

#endif



#ifndef uint32

#define uint32 unsigned long int

#endif



typedef struct

{

    uint32 esk[32];     /* DES encryption subkeys */

    uint32 dsk[32];     /* DES decryption subkeys */

} des_context;



typedef struct

{

    uint32 esk[96];     /* Triple-DES encryption subkeys */

    uint32 dsk[96];     /* Triple-DES decryption subkeys */

} des3_context;



int  des_set_key( des_context *ctx, uint8 key[8] );

void des_encrypt( des_context *ctx, uint8 input[8], uint8 output[8] );

void des_decrypt( des_context *ctx, uint8 input[8], uint8 output[8] );



int  des3_set_2keys( des3_context *ctx, uint8 key1[8], uint8 key2[8] );

int  des3_set_3keys( des3_context *ctx, uint8 key1[8], uint8 key2[8], uint8 key3[8] );



void des3_encrypt( des3_context *ctx, uint8 input[8], uint8 output[8] );

void des3_decrypt( des3_context *ctx, uint8 input[8], uint8 output[8] );



#endif /* des.h */

/*

 *  FIPS-46-3 compliant 3DES implementation

 *

 *  Copyright (C) 2001-2003  Christophe Devine

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; either version 2 of the License, or

 *  (at your option) any later version.

 *

 *  This program is distributed in the hope that it will be useful,

 *  but WITHOUT ANY WARRANTY; without even the implied warranty of

 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 *  GNU General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program; if not, write to the Free Software

 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

 */