/*

 * Copyright 2003-2005 Sun Microsystems, Inc.  All Rights Reserved.

 * 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.  Sun designates this

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

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package sun.security.pkcs11;

import java.security.*;

import java.security.spec.*;

import sun.security.pkcs11.wrapper.PKCS11Exception;

import static sun.security.pkcs11.wrapper.PKCS11Constants.*;

/**

 * KeyFactory base class. Provides common infrastructure for the RSA, DSA,

 * and DH implementations.

 *

 * The subclasses support conversion between keys and keyspecs

 * using X.509, PKCS#8, and their individual algorithm specific formats,

 * assuming keys are extractable.

 *

 * @author  Andreas Sterbenz

 * @since   1.5

 */

abstract class P11KeyFactory extends KeyFactorySpi {

    // token instance

    final Token token;

    // algorithm name, currently one of RSA, DSA, DH

    final String algorithm;

    P11KeyFactory(Token token, String algorithm) {

        super();

        this.token = token;

        this.algorithm = algorithm;

    }

    /**

     * Convert an arbitrary key of algorithm into a P11Key of token.

     * Used by P11Signature.init() and RSACipher.init().

     */

    static P11Key convertKey(Token token, Key key, String algorithm)

            throws InvalidKeyException {

        return (P11Key)token.getKeyFactory(algorithm).engineTranslateKey(key);

    }

    // see JCA spec

    protected final <T extends KeySpec> T engineGetKeySpec(Key key, Class<T> keySpec)

            throws InvalidKeySpecException {

        token.ensureValid();

        if ((key == null) || (keySpec == null)) {

            throw new InvalidKeySpecException

                ("key and keySpec must not be null");

        }

        // delegate to our Java based providers for PKCS#8 and X.509

        if (PKCS8EncodedKeySpec.class.isAssignableFrom(keySpec)

                || X509EncodedKeySpec.class.isAssignableFrom(keySpec)) {

            try {

                return (T)implGetSoftwareFactory().getKeySpec(key, keySpec);

            } catch (GeneralSecurityException e) {

                throw new InvalidKeySpecException("Could not encode key", e);

            }

        }

        // first translate into a key of this token, if it is not already

        P11Key p11Key;

        try {

            p11Key = (P11Key)engineTranslateKey(key);

        } catch (InvalidKeyException e) {

            throw new InvalidKeySpecException("Could not convert key", e);

        }

        Session[] session = new Session[1];

        try {

            if (p11Key.isPublic()) {

                return (T)implGetPublicKeySpec(p11Key, keySpec, session);

            } else {

                return (T)implGetPrivateKeySpec(p11Key, keySpec, session);

            }

        } catch (PKCS11Exception e) {

            throw new InvalidKeySpecException("Could not generate KeySpec", e);

        } finally {

            session[0] = token.releaseSession(session[0]);

        }

    }

    // see JCA spec

    protected final Key engineTranslateKey(Key key) throws InvalidKeyException {

        token.ensureValid();

        if (key == null) {

            throw new InvalidKeyException("Key must not be null");

        }

        if (key.getAlgorithm().equals(this.algorithm) == false) {

            throw new InvalidKeyException

                ("Key algorithm must be " + algorithm);

        }

        if (key instanceof P11Key) {

            P11Key p11Key = (P11Key)key;

            if (p11Key.token == token) {

                // already a key of this token, no need to translate

                return key;

            }

        }

        P11Key p11Key = token.privateCache.get(key);

        if (p11Key != null) {

            return p11Key;

        }

        if (key instanceof PublicKey) {

            PublicKey publicKey = implTranslatePublicKey((PublicKey)key);

            token.privateCache.put(key, (P11Key)publicKey);

            return publicKey;

        } else if (key instanceof PrivateKey) {

            PrivateKey privateKey = implTranslatePrivateKey((PrivateKey)key);

            token.privateCache.put(key, (P11Key)privateKey);

            return privateKey;

        } else {

            throw new InvalidKeyException

                ("Key must be instance of PublicKey or PrivateKey");

        }

    }

    abstract KeySpec implGetPublicKeySpec(P11Key key, Class keySpec,

            Session[] session) throws PKCS11Exception, InvalidKeySpecException;

    abstract KeySpec implGetPrivateKeySpec(P11Key key, Class keySpec,

            Session[] session) throws PKCS11Exception, InvalidKeySpecException;

    abstract PublicKey implTranslatePublicKey(PublicKey key)

            throws InvalidKeyException;

    abstract PrivateKey implTranslatePrivateKey(PrivateKey key)

            throws InvalidKeyException;

    abstract KeyFactory implGetSoftwareFactory() throws GeneralSecurityException;

}