The following code is a try to encrypt data using AES with asymmetric key:
import java.io.OutputStream;
import java.math.BigInteger;
import java.security.Key;
import java.security.KeyFactory;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.RSAPrivateKeySpec;
import java.security.spec.RSAPublicKeySpec;
import javax.crypto.Cipher;
public class AsyncronousKeyTest {
private final Cipher cipher;
private final KeyFactory keyFactory;
private final RSAPrivateKey privKey;
private AsyncronousKeyTest() throws Exception {
cipher = Cipher.getInstance("AES/CBC/NoPaddin", "BC");
keyFactory = KeyFactory.getInstance("AES", "BC");
// create the keys
RSAPrivateKeySpec privKeySpec = new RSAPrivateKeySpec(new BigInteger(
"d46f473a2d746537de2056ae3092c451", 16), new BigInteger("57791d5430d593164082036ad8b29fb1",
16));
privKey = (RSAPrivateKey) keyFactory.generatePrivate(privKeySpec);
}
public void generateAuthorizationAct(OutputStream outputStream) throws Exception {
KeyFactory keyFactory = KeyFactory.getInstance("AES", "BC");
RSAPublicKeySpec pubKeySpec = new RSAPublicKeySpec(new BigInteger("d46f473a2d746537de2056ae3092c451",
16), new BigInteger("11", 16));
RSAPublicKey pubKey = (RSAPublicKey) keyFactory.generatePublic(pubKeySpec);
byte[] data = new byte[] {0x01};
byte[] encrypted = encryptAO(pubKey, data);
outputStream.write(encrypted);
}
/** Encrypt the AuthorizationObject. */
public byte[] encryptAO(Key pubKey, byte[] data) throws Exception {
cipher.init(Cipher.ENCRYPT_MODE, pubKey);
byte[] cipherText = cipher.doFinal(data);
return cipherText;
}
public byte[] decrypt(byte[] cipherText) throws Exception {
cipher.init(Cipher.DECRYPT_MODE, privKey);
byte[] decyptedData = cipher.doFinal(cipherText);
return decyptedData;
}
public static void main(String[] args) throws Exception {
System.out.println("start");
AsyncronousKeyTest auth = new AsyncronousKeyTest();
auth.generateAuthorizationAct(System.out);
System.out.println("done");
}
}
but at line
cipher = Cipher.getInstance("AES/CBC/NoPaddin", "BC");
it throws
NoSuchPaddingException: Padding NoPaddin unknown.
What is this? And how to solve?