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@ximik777
Forked from bricef/AES.c
Created August 2, 2017 20:05
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A simple example of using AES encryption in Java and C.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/*
* MCrypt API available online:
* http://linux.die.net/man/3/mcrypt
*/
#include <mcrypt.h>
#include <math.h>
#include <stdint.h>
#include <stdlib.h>
int encrypt(
void* buffer,
int buffer_len, /* Because the plaintext could include null bytes*/
char* IV,
char* key,
int key_len
){
MCRYPT td = mcrypt_module_open("rijndael-128", NULL, "cbc", NULL);
int blocksize = mcrypt_enc_get_block_size(td);
if( buffer_len % blocksize != 0 ){return 1;}
mcrypt_generic_init(td, key, key_len, IV);
mcrypt_generic(td, buffer, buffer_len);
mcrypt_generic_deinit (td);
mcrypt_module_close(td);
return 0;
}
int decrypt(
void* buffer,
int buffer_len,
char* IV,
char* key,
int key_len
){
MCRYPT td = mcrypt_module_open("rijndael-128", NULL, "cbc", NULL);
int blocksize = mcrypt_enc_get_block_size(td);
if( buffer_len % blocksize != 0 ){return 1;}
mcrypt_generic_init(td, key, key_len, IV);
mdecrypt_generic(td, buffer, buffer_len);
mcrypt_generic_deinit (td);
mcrypt_module_close(td);
return 0;
}
void display(char* ciphertext, int len){
int v;
for (v=0; v<len; v++){
printf("%d ", ciphertext[v]);
}
printf("\n");
}
int main()
{
MCRYPT td, td2;
char * plaintext = "test text 123";
char* IV = "AAAAAAAAAAAAAAAA";
char *key = "0123456789abcdef";
int keysize = 16; /* 128 bits */
char* buffer;
int buffer_len = 16;
buffer = calloc(1, buffer_len);
strncpy(buffer, plaintext, buffer_len);
printf("==C==\n");
printf("plain: %s\n", plaintext);
encrypt(buffer, buffer_len, IV, key, keysize);
printf("cipher: "); display(buffer , buffer_len);
decrypt(buffer, buffer_len, IV, key, keysize);
printf("decrypt: %s\n", buffer);
return 0;
}
import java.security.MessageDigest;
import java.util.Arrays;
import javax.crypto.KeyGenerator;
import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
public class AES {
static String IV = "AAAAAAAAAAAAAAAA";
static String plaintext = "test text 123\0\0\0"; /*Note null padding*/
static String encryptionKey = "0123456789abcdef";
public static void main(String [] args) {
try {
System.out.println("==Java==");
System.out.println("plain: " + plaintext);
byte[] cipher = encrypt(plaintext, encryptionKey);
System.out.print("cipher: ");
for (int i=0; i<cipher.length; i++)
System.out.print(new Integer(cipher[i])+" ");
System.out.println("");
String decrypted = decrypt(cipher, encryptionKey);
System.out.println("decrypt: " + decrypted);
} catch (Exception e) {
e.printStackTrace();
}
}
public static byte[] encrypt(String plainText, String encryptionKey) throws Exception {
Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding", "SunJCE");
SecretKeySpec key = new SecretKeySpec(encryptionKey.getBytes("UTF-8"), "AES");
cipher.init(Cipher.ENCRYPT_MODE, key,new IvParameterSpec(IV.getBytes("UTF-8")));
return cipher.doFinal(plainText.getBytes("UTF-8"));
}
public static String decrypt(byte[] cipherText, String encryptionKey) throws Exception{
Cipher cipher = Cipher.getInstance("AES/CBC/NoPadding", "SunJCE");
SecretKeySpec key = new SecretKeySpec(encryptionKey.getBytes("UTF-8"), "AES");
cipher.init(Cipher.DECRYPT_MODE, key,new IvParameterSpec(IV.getBytes("UTF-8")));
return new String(cipher.doFinal(cipherText),"UTF-8");
}
}
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