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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package sun.security.mscapi;

import java.util.UUID;

import java.security.*;

import java.security.spec.AlgorithmParameterSpec;

import java.security.spec.RSAKeyGenParameterSpec;

import sun.security.rsa.RSAKeyFactory;

import static sun.security.util.SecurityProviderConstants.DEF_RSA_KEY_SIZE;

/**

 * RSA keypair generator.

 *

 * Standard algorithm, minimum key length is 512 bit, maximum is 16,384.

 * Generates a private key that is exportable.

 *

 * @since 1.6

 */

public abstract class CKeyPairGenerator extends KeyPairGeneratorSpi {

    protected String keyAlg;

    public CKeyPairGenerator(String keyAlg) {

        this.keyAlg = keyAlg;

    }

    public static class RSA extends CKeyPairGenerator {

        public RSA() {

            super("RSA");

            // initialize to default in case the app does not call initialize()

            initialize(DEF_RSA_KEY_SIZE, null);

        }

        // Supported by Microsoft Base, Strong and Enhanced Cryptographic Providers

        static final int KEY_SIZE_MIN = 512; // disallow MSCAPI min. of 384

        static final int KEY_SIZE_MAX = 16384;

        // size of the key to generate, KEY_SIZE_MIN <= keySize <= KEY_SIZE_MAX

        private int keySize;

        // initialize the generator. See JCA doc

        // random is always ignored

        @Override

        public void initialize(int keySize, SecureRandom random) {

            try {

                RSAKeyFactory.checkKeyLengths(keySize, null,

                        KEY_SIZE_MIN, KEY_SIZE_MAX);

            } catch (InvalidKeyException e) {

                throw new InvalidParameterException(e.getMessage());

            }

            this.keySize = keySize;

        }

        // second initialize method. See JCA doc

        // random and exponent are always ignored

        @Override

        public void initialize(AlgorithmParameterSpec params, SecureRandom random)

                throws InvalidAlgorithmParameterException {

            int tmpSize;

            if (params == null) {

                tmpSize = DEF_RSA_KEY_SIZE;

            } else if (params instanceof RSAKeyGenParameterSpec) {

                if (((RSAKeyGenParameterSpec) params).getPublicExponent() != null) {

                    throw new InvalidAlgorithmParameterException

                            ("Exponent parameter is not supported");

                }

                tmpSize = ((RSAKeyGenParameterSpec) params).getKeysize();

            } else {

                throw new InvalidAlgorithmParameterException

                        ("Params must be an instance of RSAKeyGenParameterSpec");

            }

            try {

                RSAKeyFactory.checkKeyLengths(tmpSize, null,

                        KEY_SIZE_MIN, KEY_SIZE_MAX);

            } catch (InvalidKeyException e) {

                throw new InvalidAlgorithmParameterException(

                        "Invalid Key sizes", e);

            }

            this.keySize = tmpSize;

        }

        // generate the keypair. See JCA doc

        @Override

        public KeyPair generateKeyPair() {

            try {

                // Generate each keypair in a unique key container

                CKeyPair keys =

                        generateCKeyPair(keyAlg, keySize,

                                "{" + UUID.randomUUID().toString() + "}");

                return new KeyPair(keys.getPublic(), keys.getPrivate());

            } catch (KeyException e) {

                throw new ProviderException(e);

            }

        }

        private static native CKeyPair generateCKeyPair(String alg, int keySize,

                String keyContainerName) throws KeyException;

    }

}