ed25519 extended signing

src/main/java/com/bloxbean/cardano/client/config/Configuration.java

@@ -1,7 +1,7 @@
 package com.bloxbean.cardano.client.config;
 
 import com.bloxbean.cardano.client.crypto.api.SigningProvider;
-import com.bloxbean.cardano.client.crypto.api.impl.DefaultSigningProvider;
+import com.bloxbean.cardano.client.crypto.api.impl.EdDSASigningProvider;
 import com.bloxbean.cardano.client.crypto.bip39.DefaultEntropyProviderImpl;
 import com.bloxbean.cardano.client.crypto.bip39.api.EntropyProvider;
 import com.bloxbean.cardano.client.plutus.api.PlutusObjectConverter;
@@ -15,7 +15,7 @@ public enum Configuration {
     private PlutusObjectConverter plutusObjectConverter;
 
     Configuration() {
-        signingProvider = new DefaultSigningProvider();
+        signingProvider = new EdDSASigningProvider();
         entropyProvider = new DefaultEntropyProviderImpl();
         plutusObjectConverter = new DefaultPlutusObjectConverter();
     }

src/main/java/com/bloxbean/cardano/client/crypto/api/impl/EdDSASigningProvider.java

@@ -0,0 +1,59 @@
+package com.bloxbean.cardano.client.crypto.api.impl;
+
+import com.bloxbean.cardano.client.crypto.CryptoException;
+import com.bloxbean.cardano.client.crypto.api.SigningProvider;
+import net.i2p.crypto.eddsa.EdDSAEngine;
+import net.i2p.crypto.eddsa.EdDSAPrivateKey;
+import net.i2p.crypto.eddsa.spec.EdDSANamedCurveTable;
+import net.i2p.crypto.eddsa.spec.EdDSAParameterSpec;
+import net.i2p.crypto.eddsa.spec.EdDSAPrivateKeySpec;
+
+import java.security.MessageDigest;
+import java.security.Signature;
+
+public class EdDSASigningProvider implements SigningProvider {
+    private static final EdDSAParameterSpec spec = EdDSANamedCurveTable.getByName(EdDSANamedCurveTable.ED_25519);
+
+    /**
+     * Signs provided message using Ed25519 signing algorithm with ED25519 seed (private key)
+     *
+     * @param message the byte array of the message to be signed.
+     * @param privateKey the (32 byte) ED25519 seed (private key) of the identity whose signature is going to be generated.
+     *
+     * @return the signature bytes of the signing operation's result.
+     */
+    @Override
+    public byte[] sign(byte[] message, byte[] privateKey) {
+        try{
+            Signature signature = new EdDSAEngine(MessageDigest.getInstance(spec.getHashAlgorithm()));
+            signature.initSign(new EdDSAPrivateKey(new EdDSAPrivateKeySpec(privateKey, spec)));
+            signature.setParameter(EdDSAEngine.ONE_SHOT_MODE);
+            signature.update(message);
+            return signature.sign();
+        }catch(Exception e){
+            throw new CryptoException("Signing error", e);
+        }
+    }
+
+    /**
+     * Signs provided message with Ed25519 signing algorithm using BIP32-ED25519 private key
+     *
+     * @param message the byte array of the message to be signed.
+     * @param privateKey the (64 byte) BIP32-ED25519 private key of the identity whose signature is going to be generated.
+     * @param publicKey optional (kept for backwards compatibility)
+     *
+     * @return the signature bytes of the signing operation's result.
+     */
+    @Override
+    public byte[] signExtended(byte[] message, byte[] privateKey, byte[] publicKey) {
+        try{
+            Signature signature = new EdDSAEngine(MessageDigest.getInstance(spec.getHashAlgorithm()));
+            signature.initSign(new EdDSAPrivateKey(new EdDSAPrivateKeySpec(spec, privateKey)));
+            signature.setParameter(EdDSAEngine.ONE_SHOT_MODE);
+            signature.update(message);
+            return signature.sign();
+        }catch(Exception e){
+            throw new CryptoException("Extended signing error", e);
+        }
+    }
+}