1 files changed, 142 insertions, 0 deletions
diff --git a/libraries/spongycastle/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/dh/AlgorithmParametersSpi.java b/libraries/spongycastle/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/dh/AlgorithmParametersSpi.java
new file mode 100644
index 000000000..ae89fba90
--- /dev/null
+++ b/libraries/spongycastle/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/dh/AlgorithmParametersSpi.java
@@ -0,0 +1,142 @@
+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.
+         * <p>
+         * <pre>
+         *  DHParameter ::= SEQUENCE {
+         *                   prime INTEGER, -- p
+         *                   base INTEGER, -- g
+         *                   privateValueLength INTEGER OPTIONAL}
+         * </pre>
+         */
+        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)
+            {
+                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";
+        }
+}