diff options
Diffstat (limited to 'bcprov/src/main/java/org/bouncycastle/jcajce/provider/asymmetric/elgamal/AlgorithmParameterGeneratorSpi.java')
-rw-r--r-- | bcprov/src/main/java/org/bouncycastle/jcajce/provider/asymmetric/elgamal/AlgorithmParameterGeneratorSpi.java | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/bcprov/src/main/java/org/bouncycastle/jcajce/provider/asymmetric/elgamal/AlgorithmParameterGeneratorSpi.java b/bcprov/src/main/java/org/bouncycastle/jcajce/provider/asymmetric/elgamal/AlgorithmParameterGeneratorSpi.java new file mode 100644 index 0000000..6097c3c --- /dev/null +++ b/bcprov/src/main/java/org/bouncycastle/jcajce/provider/asymmetric/elgamal/AlgorithmParameterGeneratorSpi.java @@ -0,0 +1,76 @@ +package org.bouncycastle.jcajce.provider.asymmetric.elgamal; + +import java.security.AlgorithmParameters; +import java.security.InvalidAlgorithmParameterException; +import java.security.SecureRandom; +import java.security.spec.AlgorithmParameterSpec; + +import javax.crypto.spec.DHGenParameterSpec; +import javax.crypto.spec.DHParameterSpec; + +import org.bouncycastle.crypto.generators.ElGamalParametersGenerator; +import org.bouncycastle.crypto.params.ElGamalParameters; +import org.bouncycastle.jcajce.provider.asymmetric.util.BaseAlgorithmParameterGeneratorSpi; + +public class AlgorithmParameterGeneratorSpi + extends BaseAlgorithmParameterGeneratorSpi +{ + protected SecureRandom random; + protected int strength = 1024; + + private int l = 0; + + protected void engineInit( + int strength, + SecureRandom random) + { + this.strength = strength; + this.random = random; + } + + protected void engineInit( + AlgorithmParameterSpec genParamSpec, + SecureRandom random) + throws InvalidAlgorithmParameterException + { + if (!(genParamSpec instanceof DHGenParameterSpec)) + { + throw new InvalidAlgorithmParameterException("DH parameter generator requires a DHGenParameterSpec for initialisation"); + } + DHGenParameterSpec spec = (DHGenParameterSpec)genParamSpec; + + this.strength = spec.getPrimeSize(); + this.l = spec.getExponentSize(); + this.random = random; + } + + protected AlgorithmParameters engineGenerateParameters() + { + ElGamalParametersGenerator pGen = new ElGamalParametersGenerator(); + + if (random != null) + { + pGen.init(strength, 20, random); + } + else + { + pGen.init(strength, 20, new SecureRandom()); + } + + ElGamalParameters p = pGen.generateParameters(); + + AlgorithmParameters params; + + try + { + params = createParametersInstance("ElGamal"); + params.init(new DHParameterSpec(p.getP(), p.getG(), l)); + } + catch (Exception e) + { + throw new RuntimeException(e.getMessage()); + } + + return params; + } +} |