| /* DSAParameters.java --- DSA Parameters Implementation |
| 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., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 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.provider; |
| |
| import gnu.java.io.ASN1ParsingException; |
| import gnu.java.security.der.DER; |
| import gnu.java.security.der.DERReader; |
| import gnu.java.security.der.DERValue; |
| import gnu.java.security.der.DERWriter; |
| |
| import java.io.ByteArrayOutputStream; |
| import java.io.IOException; |
| import java.math.BigInteger; |
| import java.security.AlgorithmParametersSpi; |
| import java.security.spec.AlgorithmParameterSpec; |
| import java.security.spec.DSAParameterSpec; |
| import java.security.spec.InvalidParameterSpecException; |
| import java.util.ArrayList; |
| |
| /* |
| ASN.1 Encoding for DSA from rfc2459 |
| |
| id-dsa ID ::= { iso(1) member-body(2) us(840) x9-57(10040) |
| x9cm(4) 1 } |
| |
| Dss-Parms ::= SEQUENCE { |
| p INTEGER, |
| q INTEGER, |
| g INTEGER } |
| |
| */ |
| public class DSAParameters extends AlgorithmParametersSpi |
| { |
| private BigInteger q; // the small prime |
| private BigInteger p; // the big prime |
| private BigInteger g; |
| |
| |
| public void engineInit(AlgorithmParameterSpec paramSpec) |
| throws InvalidParameterSpecException |
| { |
| if( paramSpec instanceof DSAParameterSpec ) { |
| DSAParameterSpec dsaParamSpec = (DSAParameterSpec)paramSpec; |
| p = dsaParamSpec.getP(); |
| q = dsaParamSpec.getQ(); |
| g = dsaParamSpec.getG(); |
| } |
| else |
| throw new InvalidParameterSpecException("Only accepts DSAParameterSpec"); |
| } |
| |
| public void engineInit(byte[] params) |
| throws IOException |
| { |
| DERReader in = new DERReader(params); |
| DERValue val = in.read(); |
| if (val.getValue() != DER.CONSTRUCTED_VALUE) |
| throw new ASN1ParsingException("badly formed parameters"); |
| try |
| { |
| p = (BigInteger) in.read().getValue(); |
| q = (BigInteger) in.read().getValue(); |
| g = (BigInteger) in.read().getValue(); |
| } |
| catch (Exception x) |
| { |
| throw new ASN1ParsingException("badly formed parameters"); |
| } |
| } |
| |
| public void engineInit(byte[] params, String format) |
| throws IOException |
| { |
| if( !format.equals("ASN.1") ) |
| throw new IOException("Invalid Format: Only accepts ASN.1"); |
| engineInit( params ); |
| } |
| |
| public AlgorithmParameterSpec engineGetParameterSpec(Class paramSpec) |
| throws InvalidParameterSpecException |
| { |
| if( paramSpec.isAssignableFrom(DSAParameterSpec.class) ) |
| return new DSAParameterSpec(p, q, g); |
| else |
| throw new InvalidParameterSpecException("Only accepts DSAParameterSpec"); |
| } |
| |
| public byte[] engineGetEncoded() |
| throws IOException |
| { |
| ByteArrayOutputStream bout = new ByteArrayOutputStream(); |
| ArrayList seq = new ArrayList(3); |
| seq.add(new DERValue(DER.INTEGER, p)); |
| seq.add(new DERValue(DER.INTEGER, q)); |
| seq.add(new DERValue(DER.INTEGER, g)); |
| DERWriter.write(bout, new DERValue(DER.CONSTRUCTED | DER.SEQUENCE, seq)); |
| return bout.toByteArray(); |
| } |
| |
| |
| public byte[] engineGetEncoded(String format) |
| throws IOException |
| { |
| if( !format.equals("ASN.1") ) |
| throw new IOException("Invalid Format: Only accepts ASN.1"); |
| return engineGetEncoded(); |
| } |
| |
| public String engineToString() |
| { |
| return ("q: " + q + " p: " + p + " g: " + g); |
| } |
| |
| } |