| /* AlgorithmParameterGenerator.java --- Algorithm Parameter Generator |
| Copyright (C) 1999, 2003, 2004 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
| 02110-1301 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| |
| package java.security; |
| |
| import gnu.java.security.Engine; |
| |
| import java.security.spec.AlgorithmParameterSpec; |
| |
| /** |
| * <code>AlgorithmParameterGenerator</code> is used to generate algorithm |
| * parameters for specified algorithms. |
| * |
| * <p>In case the client does not explicitly initialize the |
| * <code>AlgorithmParameterGenerator</code> (via a call to an |
| * <code>init()</code> method), each provider must supply (and document) a |
| * default initialization. For example, the <b>GNU</b> provider uses a default |
| * modulus prime size of <code>1024</code> bits for the generation of <i>DSA</i> |
| * parameters. |
| * |
| * @author Mark Benvenuto |
| * @since 1.2 |
| * @see AlgorithmParameters |
| * @see AlgorithmParameterSpec |
| */ |
| public class AlgorithmParameterGenerator |
| { |
| /** Service name for algorithm parameter generators. */ |
| private static final String ALGORITHM_PARAMETER_GENERATOR = |
| "AlgorithmParameterGenerator"; |
| |
| private AlgorithmParameterGeneratorSpi paramGenSpi; |
| private Provider provider; |
| private String algorithm; |
| |
| /** |
| * Constructs a new instance of <code>AlgorithmParameterGenerator</code>. |
| * |
| * @param paramGenSpi |
| * the generator to use. |
| * @param provider |
| * the provider to use. |
| * @param algorithm |
| * the algorithm to use. |
| */ |
| protected AlgorithmParameterGenerator(AlgorithmParameterGeneratorSpi |
| paramGenSpi, Provider provider, |
| String algorithm) |
| { |
| this.paramGenSpi = paramGenSpi; |
| this.provider = provider; |
| this.algorithm = algorithm; |
| } |
| |
| /** @return the name of the algorithm. */ |
| public final String getAlgorithm() |
| { |
| return algorithm; |
| } |
| |
| /** |
| * Returns a new <code>AlgorithmParameterGenerator</code> instance which |
| * generates algorithm parameters for the specified algorithm. |
| * |
| * @param algorithm |
| * the name of algorithm to use. |
| * @return the new instance. |
| * @throws NoSuchAlgorithmException |
| * if <code>algorithm</code> is not implemented by any provider. |
| */ |
| public static AlgorithmParameterGenerator getInstance(String algorithm) |
| throws NoSuchAlgorithmException |
| { |
| Provider[] p = Security.getProviders(); |
| for (int i = 0; i < p.length; i++) |
| try |
| { |
| return getInstance(algorithm, p[i]); |
| } |
| catch (NoSuchAlgorithmException e) |
| { |
| // Ignore. |
| } |
| |
| throw new NoSuchAlgorithmException(algorithm); |
| } |
| |
| /** |
| * Returns a new <code>AlgorithmParameterGenerator</code> instance which |
| * generates algorithm parameters for the specified algorithm. |
| * |
| * @param algorithm |
| * the name of algorithm to use. |
| * @param provider |
| * the name of the {@link Provider} to use. |
| * @return the new instance. |
| * @throws NoSuchAlgorithmException |
| * if the algorithm is not implemented by the named provider. |
| * @throws NoSuchProviderException |
| * if the named provider was not found. |
| */ |
| public static AlgorithmParameterGenerator getInstance(String algorithm, |
| String provider) |
| throws NoSuchAlgorithmException, NoSuchProviderException |
| { |
| if (provider == null || provider.length() == 0) |
| throw new IllegalArgumentException("Illegal provider"); |
| |
| Provider p = Security.getProvider(provider); |
| if (p == null) |
| throw new NoSuchProviderException(provider); |
| |
| return getInstance(algorithm, p); |
| } |
| |
| /** |
| * Returns a new <code>AlgorithmParameterGenerator</code> instance which |
| * generates algorithm parameters for the specified algorithm. |
| * |
| * @param algorithm |
| * the name of algorithm to use. |
| * @param provider |
| * the {@link Provider} to use. |
| * @return the new instance. |
| * @throws NoSuchAlgorithmException |
| * if the algorithm is not implemented by {@link Provider}. |
| * @since 1.4 |
| * @see Provider |
| */ |
| public static AlgorithmParameterGenerator getInstance(String algorithm, |
| Provider provider) |
| throws NoSuchAlgorithmException |
| { |
| if (provider == null) |
| throw new IllegalArgumentException("Illegal provider"); |
| |
| try |
| { |
| return new AlgorithmParameterGenerator( |
| (AlgorithmParameterGeneratorSpi) Engine.getInstance( |
| ALGORITHM_PARAMETER_GENERATOR, algorithm, provider), |
| provider, algorithm); |
| } |
| catch (java.lang.reflect.InvocationTargetException ite) |
| { |
| throw new NoSuchAlgorithmException(algorithm); |
| } |
| catch (ClassCastException cce) |
| { |
| throw new NoSuchAlgorithmException(algorithm); |
| } |
| } |
| |
| /** @return the {@link Provider} of this generator. */ |
| public final Provider getProvider() |
| { |
| return provider; |
| } |
| |
| /** |
| * Initializes this instance with the specified size. Since no source of |
| * randomness is supplied, a default one will be used. |
| * |
| * @param size |
| * size (in bits) to use. |
| */ |
| public final void init(int size) |
| { |
| init(size, new SecureRandom()); |
| } |
| |
| /** |
| * Initializes this instance with the specified key-size and source of |
| * randomness. |
| * |
| * @param size |
| * the size (in bits) to use. |
| * @param random |
| * the {@link SecureRandom} to use. |
| */ |
| public final void init(int size, SecureRandom random) |
| { |
| paramGenSpi.engineInit(size, random); |
| } |
| |
| /** |
| * Initializes this instance with the specified {@link AlgorithmParameterSpec}. |
| * Since no source of randomness is supplied, a default one will be used. |
| * |
| * @param genParamSpec |
| * the {@link AlgorithmParameterSpec} to use. |
| * @throws InvalidAlgorithmParameterException |
| * if <code>genParamSpec</code> is invalid. |
| */ |
| public final void init(AlgorithmParameterSpec genParamSpec) |
| throws InvalidAlgorithmParameterException |
| { |
| init(genParamSpec, new SecureRandom()); |
| } |
| |
| /** |
| * Initializes this instance with the specified {@link AlgorithmParameterSpec} |
| * and source of randomness. |
| * |
| * @param genParamSpec |
| * the {@link AlgorithmParameterSpec} to use. |
| * @param random |
| * the {@link SecureRandom} to use. |
| * @throws InvalidAlgorithmParameterException |
| * if <code>genParamSpec</code> is invalid. |
| */ |
| public final void init(AlgorithmParameterSpec genParamSpec, |
| SecureRandom random) |
| throws InvalidAlgorithmParameterException |
| { |
| paramGenSpi.engineInit(genParamSpec, random); |
| } |
| |
| /** @return a new instance of {@link AlgorithmParameters}. */ |
| public final AlgorithmParameters generateParameters() |
| { |
| return paramGenSpi.engineGenerateParameters(); |
| } |
| } |