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

   1 /* CipherFactory.java --
   2    Copyright (C) 2001, 2002, 2003, 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.util.Collections;
  44 import java.util.HashSet;
  45 import java.util.Set;
  46
  47 /**
  48  * <p>A <i>Factory</i> to instantiate symmetric block cipher instances.</p>
  49  */
  50 public class CipherFactory implements Registry
  51 {
  52
  53   // Constants and variables
  54   // -------------------------------------------------------------------------
  55
  56   // Constructor(s)
  57   // -------------------------------------------------------------------------
  58
  59   /** Trivial constructor to enforce Singleton pattern. */
  60   private CipherFactory()
  61   {
  62     super();
  63   }
  64
  65   // Class methods
  66   // -------------------------------------------------------------------------
  67
  68   /**
  69    * <p>Returns an instance of a block cipher given its name.</p>
  70    *
  71    * @param name the case-insensitive name of the symmetric-key block cipher
  72    * algorithm.
  73    * @return an instance of the designated cipher algorithm, or
  74    * <code>null</code> if none is found.
  75    * @exception InternalError if the implementation does not pass its
  76    * self-test.
  77    */
  78   public static final IBlockCipher getInstance(String name)
  79   {
  80     if (name == null)
  81       {
  82         return null;
  83       }
  84
  85     name = name.trim();
  86     IBlockCipher result = null;
  87     if (name.equalsIgnoreCase(ANUBIS_CIPHER))
  88       {
  89         result = new Anubis();
  90       }
  91     else if (name.equalsIgnoreCase(BLOWFISH_CIPHER))
  92       {
  93         result = new Blowfish();
  94       }
  95     else if (name.equalsIgnoreCase(DES_CIPHER))
  96       {
  97         result = new DES();
  98       }
  99     else if (name.equalsIgnoreCase(KHAZAD_CIPHER))
 100       {
 101         result = new Khazad();
 102       }
 103     else if (name.equalsIgnoreCase(RIJNDAEL_CIPHER)
 104              || name.equalsIgnoreCase(AES_CIPHER))
 105       {
 106         result = new Rijndael();
 107       }
 108     else if (name.equalsIgnoreCase(SERPENT_CIPHER))
 109       {
 110         result = new Serpent();
 111       }
 112     else if (name.equalsIgnoreCase(SQUARE_CIPHER))
 113       {
 114         result = new Square();
 115       }
 116     else if (name.equalsIgnoreCase(TRIPLEDES_CIPHER)
 117              || name.equalsIgnoreCase(DESEDE_CIPHER))
 118       {
 119         result = new TripleDES();
 120       }
 121     else if (name.equalsIgnoreCase(TWOFISH_CIPHER))
 122       {
 123         result = new Twofish();
 124       }
 125     else if (name.equalsIgnoreCase(CAST5_CIPHER)
 126              || (name.equalsIgnoreCase(CAST128_CIPHER) || (name.equalsIgnoreCase(CAST_128_CIPHER))))
 127       {
 128         result = new Cast5();
 129       }
 130     else if (name.equalsIgnoreCase(NULL_CIPHER))
 131       {
 132         result = new NullCipher();
 133       }
 134
 135     if (result != null && !result.selfTest())
 136       {
 137         throw new InternalError(result.name());
 138       }
 139
 140     return result;
 141   }
 142
 143   /**
 144    * <p>Returns a {@link Set} of symmetric key block cipher implementation
 145    * names supported by this <i>Factory</i>.</p>
 146    *
 147    * @return a {@link Set} of block cipher names (Strings).
 148    */
 149   public static final Set getNames()
 150   {
 151     HashSet hs = new HashSet();
 152     hs.add(ANUBIS_CIPHER);
 153     hs.add(BLOWFISH_CIPHER);
 154     hs.add(DES_CIPHER);
 155     hs.add(KHAZAD_CIPHER);
 156     hs.add(RIJNDAEL_CIPHER);
 157     hs.add(SERPENT_CIPHER);
 158     hs.add(SQUARE_CIPHER);
 159     hs.add(TRIPLEDES_CIPHER);
 160     hs.add(TWOFISH_CIPHER);
 161     hs.add(CAST5_CIPHER);
 162     hs.add(NULL_CIPHER);
 163
 164     return Collections.unmodifiableSet(hs);
 165   }
 166
 167   // Instance methods
 168   // -------------------------------------------------------------------------
 169 }