| /* DSSParametersGenerator.java -- JCE Adapter for a generator of DSS parameters |
| Copyright (C) 2006 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 gnu.java.security.jce.sig; |
| |
| import gnu.java.security.Registry; |
| import gnu.java.security.key.dss.DSSKeyPairGenerator; |
| import gnu.java.security.key.dss.FIPS186; |
| import gnu.java.security.provider.Gnu; |
| |
| import java.math.BigInteger; |
| import java.security.AlgorithmParameterGeneratorSpi; |
| import java.security.AlgorithmParameters; |
| import java.security.InvalidAlgorithmParameterException; |
| import java.security.InvalidParameterException; |
| import java.security.NoSuchAlgorithmException; |
| import java.security.Provider; |
| import java.security.SecureRandom; |
| import java.security.spec.AlgorithmParameterSpec; |
| import java.security.spec.DSAParameterSpec; |
| import java.security.spec.InvalidParameterSpecException; |
| |
| /** |
| * A JCE Adapter for a generator of DSS parameters. |
| */ |
| public class DSSParametersGenerator |
| extends AlgorithmParameterGeneratorSpi |
| { |
| private static final Provider GNU = new Gnu(); |
| |
| /** Size of the public modulus in bits. */ |
| private int modulusLength = -1; |
| |
| /** User specified source of randomness. */ |
| private SecureRandom rnd; |
| |
| /** Our concrete DSS parameters generator. */ |
| private FIPS186 fips; |
| |
| // default 0-arguments constructor |
| |
| protected void engineInit(int size, SecureRandom random) |
| { |
| if ((size % 64) != 0 || size < 512 || size > 1024) |
| throw new InvalidParameterException("Modulus size/length (in bits) MUST " |
| + "be a multiple of 64, greater than " |
| + "or equal to 512, and less than or " |
| + "equal to 1024"); |
| this.modulusLength = size; |
| this.rnd = random; |
| } |
| |
| protected void engineInit(AlgorithmParameterSpec spec, SecureRandom random) |
| throws InvalidAlgorithmParameterException |
| { |
| if (! (spec instanceof DSAParameterSpec)) |
| throw new InvalidAlgorithmParameterException("Wrong AlgorithmParameterSpec type: " |
| + spec.getClass().getName()); |
| DSAParameterSpec dsaSpec = (DSAParameterSpec) spec; |
| BigInteger p = dsaSpec.getP(); |
| int size = p.bitLength(); |
| this.engineInit(size, random); |
| } |
| |
| protected AlgorithmParameters engineGenerateParameters() |
| { |
| if (modulusLength < 1) |
| modulusLength = DSSKeyPairGenerator.DEFAULT_MODULUS_LENGTH; |
| |
| fips = new FIPS186(modulusLength, rnd); |
| BigInteger[] params = fips.generateParameters(); |
| BigInteger p = params[3]; |
| BigInteger q = params[2]; |
| BigInteger g = params[5]; |
| DSAParameterSpec spec = new DSAParameterSpec(p, q, g); |
| AlgorithmParameters result = null; |
| try |
| { |
| result = AlgorithmParameters.getInstance(Registry.DSS_KPG, GNU); |
| result.init(spec); |
| } |
| catch (NoSuchAlgorithmException ignore) |
| { |
| } |
| catch (InvalidParameterSpecException ignore) |
| { |
| } |
| return result; |
| } |
| } |