Use correct JCA format for Signature algorithm name

Closes #33.

Author: str4d

src/net/i2p/crypto/eddsa/EdDSAEngine.java

@@ -64,6 +64,8 @@
  *
  */
 public final class EdDSAEngine extends Signature {
+    public static final String SIGNATURE_ALGORITHM = "NONEwithEdDSA";
+
     private MessageDigest digest;
     private ByteArrayOutputStream baos;
     private EdDSAKey key;

src/net/i2p/crypto/eddsa/EdDSASecurityProvider.java

@@ -16,8 +16,6 @@
 import java.security.Provider;
 import java.security.Security;
 
-import net.i2p.crypto.eddsa.spec.EdDSANamedCurveTable;
-
 /**
  * A security {@link Provider} that can be registered via {@link Security#addProvider(Provider)}
  *
@@ -43,6 +41,6 @@ protected void setup() {
         // see https://docs.oracle.com/javase/8/docs/technotes/guides/security/crypto/HowToImplAProvider.html
         put("KeyPairGenerator." + EdDSAKey.KEY_ALGORITHM, "net.i2p.crypto.eddsa.KeyPairGenerator");
         put("KeyFactory." + EdDSAKey.KEY_ALGORITHM, "net.i2p.crypto.eddsa.KeyFactory");
-        put("Signature." + EdDSANamedCurveTable.CURVE_ED25519_SHA512, "net.i2p.crypto.eddsa.EdDSAEngine");
+        put("Signature." + EdDSAEngine.SIGNATURE_ALGORITHM, "net.i2p.crypto.eddsa.EdDSAEngine");
     }
 }

test/net/i2p/crypto/eddsa/EdDSASecurityProviderTest.java

@@ -38,7 +38,7 @@ public void canGetInstancesWhenProviderIsPresent() throws Exception {
 
         KeyPairGenerator keyGen = KeyPairGenerator.getInstance("EdDSA", "EdDSA");
         KeyFactory keyFac = KeyFactory.getInstance("EdDSA", "EdDSA");
-        Signature sgr = Signature.getInstance("SHA512withEd25519", "EdDSA");
+        Signature sgr = Signature.getInstance("NONEwithEdDSA", "EdDSA");
 
         Security.removeProvider("EdDSA");
     }