Example

The following example demonstrates how a DES-EDE block cipher can be constructed as a Cascade of three DES Stages.

     HashMap map = new HashMap();
     HashMap map1 = new HashMap();
     HashMap map2 = new HashMap();
     HashMap map3 = new HashMap();
     
     Cascade new3DES = new Cascade();
     Object des1 = new3DES.append(
         Stage.getInstance(
             ModeFactory.getInstance(Registry.ECB_MODE, new DES(), 8),
             Direction.FORWARD));
     Object des2 = new3DES.append(
         Stage.getInstance(
             ModeFactory.getInstance(Registry.ECB_MODE, new DES(), 8),
             Direction.REVERSED));
     Object des3 = new3DES.append(
         Stage.getInstance(
             ModeFactory.getInstance(Registry.ECB_MODE, new DES(), 8),
             Direction.FORWARD));
     
     map.put(des1, map1);
     map.put(des2, map2);
     map.put(des3, map3);
     
     map1.put(IBlockCipher.KEY_MATERIAL, key1material);
     map2.put(IBlockCipher.KEY_MATERIAL, key2material);
     map3.put(IBlockCipher.KEY_MATERIAL, key3material);
     
     // encryption
     map.put(Cascade.DIRECTION, Direction.FORWARD);
     byte[] pt = ...; // some plaintext to encrypt
     byte[] ct = new byte[pt.length]; // where ciphertext is returned
     
     try
       {
         new3DES.init(map);
         new3DES.update(pt, 0, ct, 0);
       }
     catch (InvalidKeyException x)
       {
         x.printStackTrace(System.err);
       }