Android AES and init vector
- by Donald_W
I have an issue with AES encryptio and decryption: I can change my IV entirely and still I'm able to decode my data.
public static final byte[] IV = { 65, 1, 2, 23, 4, 5, 6, 7, 32, 21, 10, 11, 12, 13, 84, 45 };
public static final byte[] IV2 = { 65, 1, 2, 23, 45, 54, 61, 81, 32, 21, 10, 121, 12, 13, 84, 45 };
public static final byte[] KEY = { 0, 42, 2, 54, 4, 45, 6, 7, 65, 9, 54, 11, 12, 13, 60, 15 };
public static final byte[] KEY2 = { 0, 42, 2, 54, 43, 45, 16, 17, 65, 9, 54, 11, 12, 13, 60, 15 };
//public static final int BITS = 256;
public static void test()
{
try
{
// encryption
Cipher c = Cipher.getInstance("AES");
SecretKeySpec keySpec = new SecretKeySpec(KEY, "AES");
c.init(Cipher.ENCRYPT_MODE, keySpec, new IvParameterSpec(IV));
String s = "Secret message";
byte[] data = s.getBytes();
byte[] encrypted = c.doFinal(data);
String encryptedStr = "";
for (int i = 0; i < encrypted.length; i++)
encryptedStr += (char) encrypted[i];
//decryoption
Cipher d_c = Cipher.getInstance("AES");
SecretKeySpec d_keySpec = new SecretKeySpec(KEY, "AES");
d_c.init(Cipher.DECRYPT_MODE, d_keySpec, new IvParameterSpec(IV2));
byte[] decrypted = d_c.doFinal(encrypted);
String decryptedStr = "";
for (int i = 0; i < decrypted.length; i++)
decryptedStr += (char) decrypted[i];
Log.d("", decryptedStr);
}
catch (Exception ex)
{
Log.d("", ex.getMessage());
}
}
Any ideas what I'm doing wrong? How can I get 256 bit AES encryption (only change key to 32-byte long array?)
Encryption is a new topic for me so please for newbie friendly answers.
