Source for javax.crypto.KeyGeneratorSpi

   1: /* KeyGeneratorSpi.java -- The key generator service provider interface.
   2:    Copyright (C) 2004  Free Software Foundation, Inc.
   3: 
   4: This file is 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, or (at your option)
   9: 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; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 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 javax.crypto;
  40: 
  41: import java.security.InvalidAlgorithmParameterException;
  42: import java.security.SecureRandom;
  43: import java.security.spec.AlgorithmParameterSpec;
  44: 
  45: /**
  46:  * The <i>Service Provider Interface</i> (<b>SPI</b>) for the {@link
  47:  * KeyGenerator} class.
  48:  *
  49:  * <p>Providers wishing to implement a key generator must subclass this
  50:  * and provide an appropriate implementation for all the abstract
  51:  * methods below, and provide an appropriate entry in the master {@link
  52:  * java.security.Provider} class (the service name for key generators is
  53:  * <code>"KeyGenerator"</code>).
  54:  *
  55:  * @author Casey Marshall (csm@gnu.org)
  56:  * @since 1.4
  57:  * @see KeyGenerator
  58:  */
  59: public abstract class KeyGeneratorSpi
  60: {
  61: 
  62:   // Constructor.
  63:   // ------------------------------------------------------------------------
  64: 
  65:   /** Create a new key generator SPI. */
  66:   public KeyGeneratorSpi()
  67:   {
  68:   }
  69: 
  70:   // Abstract instance methods.
  71:   // ------------------------------------------------------------------------
  72: 
  73:   /**
  74:    * Generate a key, returning it as a {@link SecretKey}.
  75:    *
  76:    * @return The generated key.
  77:    */
  78:   protected abstract SecretKey engineGenerateKey();
  79: 
  80:   /**
  81:    * Initialize this key generator with parameters and a source of
  82:    * randomness.
  83:    *
  84:    * @param params The parameters.
  85:    * @param random The source of randomness.
  86:    * @throws java.security.InvalidAlgorithmParameterException If the
  87:    *         parameters are inappropriate for this instance.
  88:    */
  89:   protected abstract void engineInit(AlgorithmParameterSpec params,
  90:                                      SecureRandom random)
  91:     throws InvalidAlgorithmParameterException;
  92: 
  93:   /**
  94:    * Initialize this key generator with a key size (in bits) and a
  95:    * source of randomness.
  96:    *
  97:    * @param keySize The target key size, in bits.
  98:    * @param random  The source of randomness.
  99:    * @throws java.security.InvalidParameterException If the
 100:    *         key size is illogical or unsupported.
 101:    */
 102:   protected abstract void engineInit(int keySize, SecureRandom random);
 103: 
 104:   /**
 105:    * Initialize this key generator with a source of randomness; the
 106:    * implementation should use reasonable default parameters (such as
 107:    * generated key size).
 108:    *
 109:    * @param random The source of randomness.
 110:    */
 111:   protected abstract void engineInit(SecureRandom random);
 112: }