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The file system driver family for RAES encrypted ZIP alias ZIP.RAES alias TZP files. Add the JAR artifact of this module to the run time class path to make its file system drivers available for service location in the client API modules.
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/*
 * Copyright (C) 2005-2015 Schlichtherle IT Services.
 * All rights reserved. Use is subject to license terms.
 */
package de.schlichtherle.truezip.crypto.raes.param;

import de.schlichtherle.truezip.crypto.raes.RaesKeyException;
import de.schlichtherle.truezip.crypto.raes.RaesParameters;
import de.schlichtherle.truezip.crypto.raes.RaesParametersProvider;
import de.schlichtherle.truezip.crypto.raes.Type0RaesParameters;
import de.schlichtherle.truezip.crypto.raes.Type0RaesParameters.KeyStrength;
import de.schlichtherle.truezip.key.KeyManager;
import de.schlichtherle.truezip.key.KeyManagerProvider;
import de.schlichtherle.truezip.key.KeyProvider;
import de.schlichtherle.truezip.key.UnknownKeyException;
import java.net.URI;
import javax.annotation.concurrent.ThreadSafe;

/**
 * An adapter which provides {@link RaesParameters} by using a
 * {@link KeyManager} for {@link AesCipherParameters}.
 * 
 * The current implementation supports only {@link Type0RaesParameters}.
 *
 * @author Christian Schlichtherle
 */
@ThreadSafe
public class KeyManagerRaesParameters
implements RaesParametersProvider {

    /** The key manager for accessing RAES encrypted data. */
    protected final KeyManager manager;

    /** The resource URI of the RAES file. */
    protected final URI raes;

    /**
     * Constructs RAES parameters using the given key manager provider.
     *
     * @param  provider the provider for the key manager for accessing RAES
     *         encrypted data.
     * @param  raes the absolute URI of the RAES file.
     */
    public KeyManagerRaesParameters(
            final KeyManagerProvider provider,
            final URI raes) {
        this(provider.get(AesCipherParameters.class), raes);
    }

    /**
     * Constructs new RAES parameters.
     *
     * @param  manager the key manager for accessing RAES encrypted data.
     * @param  raes the resource URI of the RAES file.
     */
    public KeyManagerRaesParameters(
            final KeyManager manager,
            final URI raes) {
        if (null == manager || null == raes)
            throw new NullPointerException();
        this.manager = manager;
        this.raes = raes;
    }

    /**
     * {@inheritDoc}
     * 

     * If {@code type} is assignable from {@link Type0RaesParameters}, then the
     * {@link KeyManager} for {@link AesCipherParameters} will get used which
     * has been provided to the constructor.
     * 

     * Otherwise, {@code null} gets returned.
     */
    @Override
    public 
 P get(Class type) {
        if (type.isAssignableFrom(Type0RaesParameters.class))
            return type.cast(new Type0());
        return null;
    }

    /**
     * Adapts a {@code KeyProvider} for {@link  AesCipherParameters} obtained
     * from the {@link #manager} to {@code Type0RaesParameters}.
     */
    private class Type0 implements Type0RaesParameters {
        @Override
        public char[] getWritePassword()
        throws RaesKeyException {
            final KeyProvider
                    provider = manager.getKeyProvider(raes);
            try {
                return provider.getWriteKey().getPassword();
            } catch (UnknownKeyException ex) {
                throw new RaesKeyException(ex);
            }
        }

        @Override
        public char[] getReadPassword(final boolean invalid)
        throws RaesKeyException {
            final KeyProvider
                    provider = manager.getKeyProvider(raes);
            try {
                return provider.getReadKey(invalid).getPassword();
            } catch (UnknownKeyException ex) {
                throw new RaesKeyException(ex);
            }
        }

        @Override
        public KeyStrength getKeyStrength()
        throws RaesKeyException {
            final KeyProvider
                    provider = manager.getKeyProvider(raes);
            try {
                return provider.getWriteKey().getKeyStrength();
            } catch (UnknownKeyException ex) {
                throw new RaesKeyException(ex);
            }
        }

        @Override
        public void setKeyStrength(final KeyStrength keyStrength)
        throws RaesKeyException {
            final KeyProvider
                    provider = manager.getKeyProvider(raes);
            final AesCipherParameters param;
            try {
                param = provider.getReadKey(false);
            } catch (UnknownKeyException ex) {
                throw new RaesKeyException(ex);
            }
            param.setKeyStrength(keyStrength);
            provider.setKey(param);
        }
    } // Type0
}