@Override
public String decrypt(ZWEncryptedData encryptedData) throws ZWKeyCrypterException {
try {
String encrypted = encryptedData.getEncryptedData();
Cipher decryptionCipher = Cipher.getInstance(CIPHER_ALGORITHM);
int ivLength = decryptionCipher.getBlockSize();
String ivHex = encrypted.substring(0, ivLength * 2);
String encryptedHex = encrypted.substring(ivLength * 2);
IvParameterSpec ivspec = new IvParameterSpec(ZiftrUtils.hexStringToBytes(ivHex));
decryptionCipher.init(Cipher.DECRYPT_MODE, this.secretKey, ivspec);
byte[] decryptedText = decryptionCipher.doFinal(ZiftrUtils.hexStringToBytes(encryptedHex));
String decrypted = new String(decryptedText, "UTF-8");
return decrypted;
} catch (Exception e) {
throw new ZWKeyCrypterException("Unable to decrypt", e);
}
}
public static SecretKey generateSecretKey(String password, String salt)
throws ZWKeyCrypterException {
try {
PBEKeySpec pbeKeySpec =
new PBEKeySpec(
password.toCharArray(),
ZiftrUtils.hexStringToBytes(salt),
PBE_ITERATION_COUNT,
KEY_LENGTH);
SecretKeyFactory factory = SecretKeyFactory.getInstance(PBE_ALGORITHM);
SecretKey tmp = factory.generateSecret(pbeKeySpec);
SecretKey secret = new SecretKeySpec(tmp.getEncoded(), SECRET_KEY_ALGORITHM);
return secret;
} catch (Exception e) {
throw new ZWKeyCrypterException("Unable to get secret key", e);
}
}
@Override
public byte[] decryptToBytes(ZWEncryptedData encryptedData) throws ZWKeyCrypterException {
return ZiftrUtils.hexStringToBytes(decrypt(encryptedData));
}
