1 files changed, 103 insertions, 0 deletions
diff --git a/libraries/spongycastle/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/dsa/AlgorithmParameterGeneratorSpi.java b/libraries/spongycastle/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/dsa/AlgorithmParameterGeneratorSpi.java
new file mode 100644
index 000000000..9bbdca3d3
--- /dev/null
+++ b/libraries/spongycastle/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/dsa/AlgorithmParameterGeneratorSpi.java
@@ -0,0 +1,103 @@
+package org.spongycastle.jcajce.provider.asymmetric.dsa;
+
+import java.security.AlgorithmParameters;
+import java.security.InvalidAlgorithmParameterException;
+import java.security.InvalidParameterException;
+import java.security.SecureRandom;
+import java.security.spec.AlgorithmParameterSpec;
+import java.security.spec.DSAParameterSpec;
+
+import org.spongycastle.crypto.digests.SHA256Digest;
+import org.spongycastle.crypto.generators.DSAParametersGenerator;
+import org.spongycastle.crypto.params.DSAParameterGenerationParameters;
+import org.spongycastle.crypto.params.DSAParameters;
+import org.spongycastle.jce.provider.BouncyCastleProvider;
+
+public class AlgorithmParameterGeneratorSpi
+    extends java.security.AlgorithmParameterGeneratorSpi
+{
+    protected SecureRandom random;
+    protected int strength = 1024;
+    protected DSAParameterGenerationParameters params;
+
+    protected void engineInit(
+        int strength,
+        SecureRandom random)
+    {
+        if (strength < 512 || strength > 3072)
+        {
+            throw new InvalidParameterException("strength must be from 512 - 3072");
+        }
+
+        if (strength <= 1024 && strength % 64 != 0)
+        {
+            throw new InvalidParameterException("strength must be a multiple of 64 below 1024 bits.");
+        }
+
+        if (strength > 1024 && strength % 1024 != 0)
+        {
+            throw new InvalidParameterException("strength must be a multiple of 1024 above 1024 bits.");
+        }
+
+        this.strength = strength;
+        this.random = random;
+    }
+
+    protected void engineInit(
+        AlgorithmParameterSpec genParamSpec,
+        SecureRandom random)
+        throws InvalidAlgorithmParameterException
+    {
+        throw new InvalidAlgorithmParameterException("No supported AlgorithmParameterSpec for DSA parameter generation.");
+    }
+
+    protected AlgorithmParameters engineGenerateParameters()
+    {
+        DSAParametersGenerator pGen;
+
+        if (strength <= 1024)
+        {
+            pGen = new DSAParametersGenerator();
+        }
+        else
+        {
+            pGen = new DSAParametersGenerator(new SHA256Digest());
+        }
+
+        if (random == null)
+        {
+            random = new SecureRandom();
+        }
+
+        if (strength == 1024)
+        {
+            params = new DSAParameterGenerationParameters(1024, 160, 80, random);
+            pGen.init(params);
+        }
+        else if (strength > 1024)
+        {
+            params = new DSAParameterGenerationParameters(strength, 256, 80, random);
+            pGen.init(params);
+        }
+        else
+        {
+            pGen.init(strength, 20, random);
+        }
+
+        DSAParameters p = pGen.generateParameters();
+
+        AlgorithmParameters params;
+
+        try
+        {
+            params = AlgorithmParameters.getInstance("DSA", BouncyCastleProvider.PROVIDER_NAME);
+            params.init(new DSAParameterSpec(p.getP(), p.getQ(), p.getG()));
+        }
+        catch (Exception e)
+        {
+            throw new RuntimeException(e.getMessage());
+        }
+
+        return params;
+    }
+}