1 files changed, 50 insertions, 0 deletions
diff --git a/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/util/DHUtil.java b/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/util/DHUtil.java
new file mode 100644
index 00000000..10b633da
--- /dev/null
+++ b/prov/src/main/java/org/spongycastle/jcajce/provider/asymmetric/util/DHUtil.java
@@ -0,0 +1,50 @@
+package org.spongycastle.jcajce.provider.asymmetric.util;
+
+import java.security.InvalidKeyException;
+import java.security.PrivateKey;
+import java.security.PublicKey;
+
+import javax.crypto.interfaces.DHPrivateKey;
+import javax.crypto.interfaces.DHPublicKey;
+
+import org.spongycastle.crypto.params.AsymmetricKeyParameter;
+import org.spongycastle.crypto.params.DHParameters;
+import org.spongycastle.crypto.params.DHPrivateKeyParameters;
+import org.spongycastle.crypto.params.DHPublicKeyParameters;
+
+/**
+ * utility class for converting jce/jca DH objects
+ * objects into their org.spongycastle.crypto counterparts.
+ */
+public class DHUtil
+{
+    static public AsymmetricKeyParameter generatePublicKeyParameter(
+        PublicKey    key)
+        throws InvalidKeyException
+    {
+        if (key instanceof DHPublicKey)
+        {
+            DHPublicKey    k = (DHPublicKey)key;
+
+            return new DHPublicKeyParameters(k.getY(),
+                new DHParameters(k.getParams().getP(), k.getParams().getG(), null, k.getParams().getL()));
+        }
+
+        throw new InvalidKeyException("can't identify DH public key.");
+    }
+
+    static public AsymmetricKeyParameter generatePrivateKeyParameter(
+        PrivateKey    key)
+        throws InvalidKeyException
+    {
+        if (key instanceof DHPrivateKey)
+        {
+            DHPrivateKey    k = (DHPrivateKey)key;
+
+            return new DHPrivateKeyParameters(k.getX(),
+                new DHParameters(k.getParams().getP(), k.getParams().getG(), null, k.getParams().getL()));
+        }
+                        
+        throw new InvalidKeyException("can't identify DH private key.");
+    }
+}