Java by API/javax.crypto/CipherInputStream

javax.crypto.CipherInputStream

   <source lang="java">
 

import java.io.BufferedReader; import java.io.FileInputStream; import java.io.InputStreamReader; import java.io.ObjectInputStream; import javax.crypto.Cipher; import javax.crypto.CipherInputStream; import javax.crypto.SecretKey; import javax.crypto.SecretKeyFactory; import javax.crypto.spec.DESKeySpec; import javax.crypto.spec.IvParameterSpec; public class MainClass {

 public static void main(String args[]) throws Exception {
   ObjectInputStream ois = new ObjectInputStream(new FileInputStream("keyfile"));
   DESKeySpec ks = new DESKeySpec((byte[]) ois.readObject());
   SecretKeyFactory skf = SecretKeyFactory.getInstance("DES");
   SecretKey key = skf.generateSecret(ks);
   Cipher c = Cipher.getInstance("DES/CFB8/NoPadding");
   c.init(Cipher.DECRYPT_MODE, key, new IvParameterSpec((byte[]) ois.readObject()));
   CipherInputStream cis = new CipherInputStream(new FileInputStream("ciphertext"), c);
   BufferedReader br = new BufferedReader(new InputStreamReader(cis));
   System.out.println(br.readLine());
 }

}

 </source>