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. 015 016 You should have received a copy of the GNU General Public License 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 }