001 /* KeyGeneratorSpi.java -- The key generator service provider interface.
002 Copyright (C) 2004 Free Software Foundation, Inc.
003
004 This file is part of GNU Classpath.
005
006 GNU Classpath is free software; you can redistribute it and/or modify
007 it under the terms of the GNU General Public License as published by
008 the Free Software Foundation; either version 2, or (at your option)
009 any later version.
010
011 GNU Classpath is distributed in the hope that it will be useful, but
012 WITHOUT ANY WARRANTY; without even the implied warranty of
013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
014 General Public License for more details.
015
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017 along with GNU Classpath; see the file COPYING. If not, write to the
018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019 02110-1301 USA.
020
021 Linking this library statically or dynamically with other modules is
022 making a combined work based on this library. Thus, the terms and
023 conditions of the GNU General Public License cover the whole
024 combination.
025
026 As a special exception, the copyright holders of this library give you
027 permission to link this library with independent modules to produce an
028 executable, regardless of the license terms of these independent
029 modules, and to copy and distribute the resulting executable under
030 terms of your choice, provided that you also meet, for each linked
031 independent module, the terms and conditions of the license of that
032 module. An independent module is a module which is not derived from
033 or based on this library. If you modify this library, you may extend
034 this exception to your version of the library, but you are not
035 obligated to do so. If you do not wish to do so, delete this
036 exception statement from your version. */
037
038
039 package javax.crypto;
040
041 import java.security.InvalidAlgorithmParameterException;
042 import java.security.SecureRandom;
043 import java.security.spec.AlgorithmParameterSpec;
044
045 /**
046 * The <i>Service Provider Interface</i> (<b>SPI</b>) for the {@link
047 * KeyGenerator} class.
048 *
049 * <p>Providers wishing to implement a key generator must subclass this
050 * and provide an appropriate implementation for all the abstract
051 * methods below, and provide an appropriate entry in the master {@link
052 * java.security.Provider} class (the service name for key generators is
053 * <code>"KeyGenerator"</code>).
054 *
055 * @author Casey Marshall (csm@gnu.org)
056 * @since 1.4
057 * @see KeyGenerator
058 */
059 public abstract class KeyGeneratorSpi
060 {
061
062 // Constructor.
063 // ------------------------------------------------------------------------
064
065 /** Create a new key generator SPI. */
066 public KeyGeneratorSpi()
067 {
068 }
069
070 // Abstract instance methods.
071 // ------------------------------------------------------------------------
072
073 /**
074 * Generate a key, returning it as a {@link SecretKey}.
075 *
076 * @return The generated key.
077 */
078 protected abstract SecretKey engineGenerateKey();
079
080 /**
081 * Initialize this key generator with parameters and a source of
082 * randomness.
083 *
084 * @param params The parameters.
085 * @param random The source of randomness.
086 * @throws java.security.InvalidAlgorithmParameterException If the
087 * parameters are inappropriate for this instance.
088 */
089 protected abstract void engineInit(AlgorithmParameterSpec params,
090 SecureRandom random)
091 throws InvalidAlgorithmParameterException;
092
093 /**
094 * Initialize this key generator with a key size (in bits) and a
095 * source of randomness.
096 *
097 * @param keySize The target key size, in bits.
098 * @param random The source of randomness.
099 * @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 }