libjava/classpath/gnu/javax/crypto/cipher/NullCipher.java

   1 /* NullCipher.java --
   2    Copyright (C) 2001, 2002, 2006 Free Software Foundation, Inc.
   3
   4 This file is a part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or (at
   9 your option) any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; if not, write to the Free Software
  18 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301
  19 USA
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version.  */
  37
  38
  39 package gnu.javax.crypto.cipher;
  40
  41 import gnu.java.security.Registry;
  42
  43 import java.security.InvalidKeyException;
  44 import java.util.ArrayList;
  45 import java.util.Collections;
  46 import java.util.Iterator;
  47
  48 /**
  49  * <p>The implementation of a Null block cipher.</p>
  50  *
  51  * <p>This cipher does not alter its input at all, claims to process block sizes
  52  * 128-, 192- and 256-bit long, and key sizes from 64- to 512-bit in 8-bit
  53  * increments.</p>
  54  */
  55 public final class NullCipher extends BaseCipher
  56 {
  57
  58   // Constants and variables
  59   // -------------------------------------------------------------------------
  60
  61   // Constructor(s)
  62   // -------------------------------------------------------------------------
  63
  64   /** Trivial 0-arguments constructor. */
  65   public NullCipher()
  66   {
  67     super(Registry.NULL_CIPHER, 16, 16);
  68   }
  69
  70   // Class methods
  71   // -------------------------------------------------------------------------
  72
  73   // Instance methods
  74   // -------------------------------------------------------------------------
  75
  76   // java.lang.Cloneable interface implementation ----------------------------
  77
  78   public Object clone()
  79   {
  80     NullCipher result = new NullCipher();
  81     result.currentBlockSize = this.currentBlockSize;
  82
  83     return result;
  84   }
  85
  86   // IBlockCipherSpi interface implementation --------------------------------
  87
  88   public Iterator blockSizes()
  89   {
  90     ArrayList al = new ArrayList();
  91     al.add(new Integer(64 / 8));
  92     al.add(new Integer(128 / 8));
  93     al.add(new Integer(192 / 8));
  94     al.add(new Integer(256 / 8));
  95
  96     return Collections.unmodifiableList(al).iterator();
  97   }
  98
  99   public Iterator keySizes()
 100   {
 101     ArrayList al = new ArrayList();
 102     for (int n = 8; n < 64; n++)
 103       {
 104         al.add(new Integer(n));
 105       }
 106
 107     return Collections.unmodifiableList(al).iterator();
 108   }
 109
 110   public Object makeKey(byte[] uk, int bs) throws InvalidKeyException
 111   {
 112     return new Object();
 113   }
 114
 115   public void encrypt(byte[] in, int i, byte[] out, int j, Object k, int bs)
 116   {
 117     System.arraycopy(in, i, out, j, bs);
 118   }
 119
 120   public void decrypt(byte[] in, int i, byte[] out, int j, Object k, int bs)
 121   {
 122     System.arraycopy(in, i, out, j, bs);
 123   }
 124
 125   public boolean selfTest()
 126   {
 127     return true;
 128   }
 129 }