des加密算法程序

tar xjvf libmcrypt-2.5.8.tar.bz2

cd libmcrypt-2.5.8

./configure --prefix=/Volumes/2g/code/php_socket/libmcrypt

make

make install

vi mcrypt.c

#include <stdlib.h>

#include <stdio.h>

#include <string.h>

#include <mcrypt.h>

int main(int argc,char *argv[])

{

int i;

char *IV,*key;

int iv_size;

int key_size;

int bsize;

char *string="Wel123$ Linux Windows This is test";

MCRYPT td=mcrypt_module_open("des",NULL,"ecb",NULL);

if(td==MCRYPT_FAILED)

{

exit(0);

}

iv_size=mcrypt_enc_get_iv_size(td);

key_size=mcrypt_enc_get_key_size(td);

key=calloc(1,key_size);

memcpy(key,"pass",key_size);

IV=calloc(1,iv_size);

for(i=0;i<iv_size;i++)

{

IV[i]=0;

}

i=mcrypt_generic_init(td,key,key_size,IV);

bsize=mcrypt_enc_get_block_size(td);

char *b_buffer=calloc(1,bsize);

int delen=(strlen(string)+bsize-1)/bsize*bsize;

char *target=calloc(1,delen);

memcpy(target,string,strlen(string));

printf("\n%s\nlength=%d\n",target,delen);

mdecrypt_generic(td,target,delen);

  printf("\nsource=%d\ndest=%d\n",(int)strlen(string),(int)strlen(target));

printf("\n");

for(i=0;i<strlen(target);i++)

{

printf("%2x",(char)*(target+i));

}

printf("\n");

mcrypt_generic_deinit(td);

mcrypt_module_close(td);

}

编译

gcc mcrypt.c -o mcrypt

-I/Volumes/2g/code/php_socket/libmcrypt/include -L/Volumes/2g/code/php_socket/libmcrypt/lib/ -lmcrypt