JcaEdKeyPairGenerator.java

/*
 * GordianKnot: Security Suite
 * Copyright 2026. Tony Washer
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License.  You may obtain a copy
 * of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package io.github.tonywasher.joceanus.gordianknot.impl.jca.keypair;

import io.github.tonywasher.joceanus.gordianknot.api.base.GordianException;
import io.github.tonywasher.joceanus.gordianknot.api.keypair.spec.GordianKeyPairSpec;
import io.github.tonywasher.joceanus.gordianknot.impl.core.base.GordianBaseFactory;
import io.github.tonywasher.joceanus.gordianknot.impl.core.exc.GordianCryptoException;
import io.github.tonywasher.joceanus.gordianknot.impl.core.exc.GordianLogicException;
import io.github.tonywasher.joceanus.gordianknot.impl.core.spec.keypair.GordianCoreKeyPairSpec;
import org.bouncycastle.jcajce.spec.EdDSAParameterSpec;
import org.bouncycastle.jcajce.spec.XDHParameterSpec;

import java.security.InvalidAlgorithmParameterException;
import java.security.spec.AlgorithmParameterSpec;

/**
 * Jca Edwards KeyPair generator.
 */
public class JcaEdKeyPairGenerator
        extends JcaKeyPairGenerator {
    /**
     * Constructor.
     *
     * @param pFactory the Security Factory
     * @param pKeySpec the keySpec
     * @throws GordianException on error
     */
    protected JcaEdKeyPairGenerator(final GordianBaseFactory pFactory,
                                    final GordianKeyPairSpec pKeySpec) throws GordianException {
        /* initialize underlying class */
        super(pFactory, pKeySpec);

        /* Protect against exceptions */
        try {
            /* Create the parameters */
            final AlgorithmParameterSpec myAlgo;
            final GordianCoreKeyPairSpec myKeySpec = (GordianCoreKeyPairSpec) pKeySpec;
            final boolean is25519 = myKeySpec.getEdwardsSpec().is25519();
            myAlgo = switch (pKeySpec.getKeyPairType()) {
                case XDH -> is25519
                        ? new XDHParameterSpec(XDHParameterSpec.X25519)
                        : new XDHParameterSpec(XDHParameterSpec.X448);
                case EDDSA -> is25519
                        ? new EdDSAParameterSpec(EdDSAParameterSpec.Ed25519)
                        : new EdDSAParameterSpec(EdDSAParameterSpec.Ed448);
                default -> throw new GordianLogicException("Invalid KeySpec" + pKeySpec);
            };

            /* Create and initialize the generator */
            final String myJavaType = pKeySpec.toString();
            createFactories(myJavaType, false);
            getGenerator().initialize(myAlgo, getRandom());

        } catch (InvalidAlgorithmParameterException e) {
            throw new GordianCryptoException("Failed to create EdwardsGenerator", e);
        }
    }
}