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package org.spongycastle.jcajce.provider.asymmetric.elgamal;
import java.security.InvalidAlgorithmParameterException;
import java.security.KeyPair;
import java.security.SecureRandom;
import java.security.spec.AlgorithmParameterSpec;
import javax.crypto.spec.DHParameterSpec;
import org.spongycastle.crypto.AsymmetricCipherKeyPair;
import org.spongycastle.crypto.generators.ElGamalKeyPairGenerator;
import org.spongycastle.crypto.generators.ElGamalParametersGenerator;
import org.spongycastle.crypto.params.ElGamalKeyGenerationParameters;
import org.spongycastle.crypto.params.ElGamalParameters;
import org.spongycastle.crypto.params.ElGamalPrivateKeyParameters;
import org.spongycastle.crypto.params.ElGamalPublicKeyParameters;
import org.spongycastle.jce.provider.BouncyCastleProvider;
import org.spongycastle.jce.spec.ElGamalParameterSpec;
public class KeyPairGeneratorSpi
extends java.security.KeyPairGenerator
{
ElGamalKeyGenerationParameters param;
ElGamalKeyPairGenerator engine = new ElGamalKeyPairGenerator();
int strength = 1024;
int certainty = 20;
SecureRandom random = new SecureRandom();
boolean initialised = false;
public KeyPairGeneratorSpi()
{
super("ElGamal");
}
public void initialize(
int strength,
SecureRandom random)
{
this.strength = strength;
this.random = random;
}
public void initialize(
AlgorithmParameterSpec params,
SecureRandom random)
throws InvalidAlgorithmParameterException
{
if (!(params instanceof ElGamalParameterSpec) && !(params instanceof DHParameterSpec))
{
throw new InvalidAlgorithmParameterException("parameter object not a DHParameterSpec or an ElGamalParameterSpec");
}
if (params instanceof ElGamalParameterSpec)
{
ElGamalParameterSpec elParams = (ElGamalParameterSpec)params;
param = new ElGamalKeyGenerationParameters(random, new ElGamalParameters(elParams.getP(), elParams.getG()));
}
else
{
DHParameterSpec dhParams = (DHParameterSpec)params;
param = new ElGamalKeyGenerationParameters(random, new ElGamalParameters(dhParams.getP(), dhParams.getG(), dhParams.getL()));
}
engine.init(param);
initialised = true;
}
public KeyPair generateKeyPair()
{
if (!initialised)
{
DHParameterSpec dhParams = BouncyCastleProvider.CONFIGURATION.getDHDefaultParameters(strength);
if (dhParams != null)
{
param = new ElGamalKeyGenerationParameters(random, new ElGamalParameters(dhParams.getP(), dhParams.getG(), dhParams.getL()));
}
else
{
ElGamalParametersGenerator pGen = new ElGamalParametersGenerator();
pGen.init(strength, certainty, random);
param = new ElGamalKeyGenerationParameters(random, pGen.generateParameters());
}
engine.init(param);
initialised = true;
}
AsymmetricCipherKeyPair pair = engine.generateKeyPair();
ElGamalPublicKeyParameters pub = (ElGamalPublicKeyParameters)pair.getPublic();
ElGamalPrivateKeyParameters priv = (ElGamalPrivateKeyParameters)pair.getPrivate();
return new KeyPair(new BCElGamalPublicKey(pub),
new BCElGamalPrivateKey(priv));
}
}
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