All Downloads are FREE. Search and download functionalities are using the official Maven repository.

org.spongycastle.jcajce.provider.asymmetric.dh.AlgorithmParametersSpi Maven / Gradle / Ivy

Go to download

Spongy Castle is a package-rename (org.bouncycastle.* to org.spongycastle.*) of Bouncy Castle intended for the Android platform. Android unfortunately ships with a stripped-down version of Bouncy Castle, which prevents easy upgrades - Spongy Castle overcomes this and provides a full, up-to-date version of the Bouncy Castle cryptographic libs.

The newest version!
package org.spongycastle.jcajce.provider.asymmetric.dh;

import java.io.IOException;
import java.security.spec.AlgorithmParameterSpec;
import java.security.spec.InvalidParameterSpecException;

import javax.crypto.spec.DHParameterSpec;

import org.spongycastle.asn1.ASN1Encoding;
import org.spongycastle.asn1.pkcs.DHParameter;

public class AlgorithmParametersSpi
    extends java.security.AlgorithmParametersSpi
{
    DHParameterSpec     currentSpec;

    protected boolean isASN1FormatString(String format)
    {
        return format == null || format.equals("ASN.1");
    }

    protected AlgorithmParameterSpec engineGetParameterSpec(
        Class paramSpec)
        throws InvalidParameterSpecException
    {
        if (paramSpec == null)
        {
            throw new NullPointerException("argument to getParameterSpec must not be null");
        }

        return localEngineGetParameterSpec(paramSpec);
    }




        /**
         * Return the PKCS#3 ASN.1 structure DHParameter.
         * 

*

         *  DHParameter ::= SEQUENCE {
         *                   prime INTEGER, -- p
         *                   base INTEGER, -- g
         *                   privateValueLength INTEGER OPTIONAL}
         * 
*/ protected byte[] engineGetEncoded() { DHParameter dhP = new DHParameter(currentSpec.getP(), currentSpec.getG(), currentSpec.getL()); try { return dhP.getEncoded(ASN1Encoding.DER); } catch (IOException e) { throw new RuntimeException("Error encoding DHParameters"); } } protected byte[] engineGetEncoded( String format) { if (isASN1FormatString(format)) { return engineGetEncoded(); } return null; } protected AlgorithmParameterSpec localEngineGetParameterSpec( Class paramSpec) throws InvalidParameterSpecException { if (paramSpec == DHParameterSpec.class || paramSpec == AlgorithmParameterSpec.class) { return currentSpec; } throw new InvalidParameterSpecException("unknown parameter spec passed to DH parameters object."); } protected void engineInit( AlgorithmParameterSpec paramSpec) throws InvalidParameterSpecException { if (!(paramSpec instanceof DHParameterSpec)) { throw new InvalidParameterSpecException("DHParameterSpec required to initialise a Diffie-Hellman algorithm parameters object"); } this.currentSpec = (DHParameterSpec)paramSpec; } protected void engineInit( byte[] params) throws IOException { try { DHParameter dhP = DHParameter.getInstance(params); if (dhP.getL() != null) { currentSpec = new DHParameterSpec(dhP.getP(), dhP.getG(), dhP.getL().intValue()); } else { currentSpec = new DHParameterSpec(dhP.getP(), dhP.getG()); } } catch (ClassCastException e) { throw new IOException("Not a valid DH Parameter encoding."); } catch (ArrayIndexOutOfBoundsException e) { throw new IOException("Not a valid DH Parameter encoding."); } } protected void engineInit( byte[] params, String format) throws IOException { if (isASN1FormatString(format)) { engineInit(params); } else { throw new IOException("Unknown parameter format " + format); } } protected String engineToString() { return "Diffie-Hellman Parameters"; } }




© 2015 - 2024 Weber Informatics LLC | Privacy Policy