1 files changed, 132 insertions, 0 deletions
diff --git a/libraries/spongycastle/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/dsa/AlgorithmParametersSpi.java b/libraries/spongycastle/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/dsa/AlgorithmParametersSpi.java
new file mode 100644
index 000000000..2ace504db
--- /dev/null
+++ b/libraries/spongycastle/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/dsa/AlgorithmParametersSpi.java
@@ -0,0 +1,132 @@
+package org.spongycastle.jcajce.provider.asymmetric.dsa;
+
+import java.io.IOException;
+import java.security.spec.AlgorithmParameterSpec;
+import java.security.spec.DSAParameterSpec;
+import java.security.spec.InvalidParameterSpecException;
+
+import org.spongycastle.asn1.ASN1Encoding;
+import org.spongycastle.asn1.ASN1Primitive;
+import org.spongycastle.asn1.x509.DSAParameter;
+
+public class AlgorithmParametersSpi
+    extends java.security.AlgorithmParametersSpi
+{
+    DSAParameterSpec 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 X.509 ASN.1 structure DSAParameter.
+     * <p/>
+     * <pre>
+     *  DSAParameter ::= SEQUENCE {
+     *                   prime INTEGER, -- p
+     *                   subprime INTEGER, -- q
+     *                   base INTEGER, -- g}
+     * </pre>
+     */
+    protected byte[] engineGetEncoded()
+    {
+        DSAParameter dsaP = new DSAParameter(currentSpec.getP(), currentSpec.getQ(), currentSpec.getG());
+
+        try
+        {
+            return dsaP.getEncoded(ASN1Encoding.DER);
+        }
+        catch (IOException e)
+        {
+            throw new RuntimeException("Error encoding DSAParameters");
+        }
+    }
+
+    protected byte[] engineGetEncoded(
+        String format)
+    {
+        if (isASN1FormatString(format))
+        {
+            return engineGetEncoded();
+        }
+
+        return null;
+    }
+
+    protected AlgorithmParameterSpec localEngineGetParameterSpec(
+        Class paramSpec)
+        throws InvalidParameterSpecException
+    {
+        if (paramSpec == DSAParameterSpec.class)
+        {
+            return currentSpec;
+        }
+
+        throw new InvalidParameterSpecException("unknown parameter spec passed to DSA parameters object.");
+    }
+
+    protected void engineInit(
+        AlgorithmParameterSpec paramSpec)
+        throws InvalidParameterSpecException
+    {
+        if (!(paramSpec instanceof DSAParameterSpec))
+        {
+            throw new InvalidParameterSpecException("DSAParameterSpec required to initialise a DSA algorithm parameters object");
+        }
+
+        this.currentSpec = (DSAParameterSpec)paramSpec;
+    }
+
+    protected void engineInit(
+        byte[] params)
+        throws IOException
+    {
+        try
+        {
+            DSAParameter dsaP = DSAParameter.getInstance(ASN1Primitive.fromByteArray(params));
+
+            currentSpec = new DSAParameterSpec(dsaP.getP(), dsaP.getQ(), dsaP.getG());
+        }
+        catch (ClassCastException e)
+        {
+            throw new IOException("Not a valid DSA Parameter encoding.");
+        }
+        catch (ArrayIndexOutOfBoundsException e)
+        {
+            throw new IOException("Not a valid DSA Parameter encoding.");
+        }
+    }
+
+    protected void engineInit(
+        byte[] params,
+        String format)
+        throws IOException
+    {
+        if (isASN1FormatString(format) || format.equalsIgnoreCase("X.509"))
+        {
+            engineInit(params);
+        }
+        else
+        {
+            throw new IOException("Unknown parameter format " + format);
+        }
+    }
+
+    protected String engineToString()
+    {
+        return "DSA Parameters";
+    }
+}