de.schlichtherle.truezip.fs.archive.zip.raes.ZipRaesController Maven / Gradle / Ivy

Go to download
/*
 * Copyright (C) 2011 Schlichtherle IT Services
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 */
package de.schlichtherle.truezip.fs.archive.zip.raes;

import de.schlichtherle.truezip.crypto.raes.RaesKeyException;
import de.schlichtherle.truezip.crypto.raes.param.AesCipherParameters;
import de.schlichtherle.truezip.entry.Entry;
import static de.schlichtherle.truezip.entry.Entry.Type.*;
import de.schlichtherle.truezip.fs.FsController;
import de.schlichtherle.truezip.fs.FsEntry;
import de.schlichtherle.truezip.fs.FsEntryName;
import static de.schlichtherle.truezip.fs.FsEntryName.*;
import de.schlichtherle.truezip.fs.FsFalsePositiveException;
import de.schlichtherle.truezip.fs.archive.FsArchiveEntry;
import de.schlichtherle.truezip.fs.archive.FsCovariantEntry;
import de.schlichtherle.truezip.fs.archive.zip.KeyManagerController;
import edu.umd.cs.findbugs.annotations.DefaultAnnotation;
import edu.umd.cs.findbugs.annotations.NonNull;
import java.io.IOException;
import net.jcip.annotations.ThreadSafe;

/**
 * This file system controller decorates another file system controller in
 * order to manage the authentication key required for accessing its target
 * RAES encrypted ZIP archive file (ZIP.RAES).
 * 
 * @author  Christian Schlichtherle
 * @version $Id$
 */
@ThreadSafe
@DefaultAnnotation(NonNull.class)
public class ZipRaesController
extends KeyManagerController {

    private static final String ROOT_PATH = ROOT.getPath();

    /**
     * Constructs a new ZIP.RAES archive controller.
     *
     * @param controller the non-{@code null} file system controller to
     *        decorate.
     * @param driver the ZIP.RAES driver.
     */
    ZipRaesController(
            final FsController controller,
            final ZipRaesDriver driver) {
        super(controller, driver);
    }

    @Override
    protected Class getKeyType() {
        return AesCipherParameters.class;
    }

    @Override
    protected Class getKeyExceptionType() {
        return RaesKeyException.class;
    }

    @Override
    public FsEntry getEntry(final FsEntryName name)
    throws IOException {
        try {
            return delegate.getEntry(name);
        } catch (final FsFalsePositiveException ex) {
            if (!(ex.getCause() instanceof RaesKeyException))
                throw ex;
            if (!name.isRoot())
                return null;
            Entry entry = getParent().getEntry(
                    getModel()
                        .getMountPoint()
                        .getPath()
                        .resolve(name)
                        .getEntryName());
            assert null != entry;
            // The entry is inaccessible for some reason.
            // This may be because the cipher key is not available.
            // Now mask the entry as a special file.
            while (entry instanceof FsCovariantEntry)
                entry = ((FsCovariantEntry) entry).getEntry();
            final FsCovariantEntry
                    special = new FsCovariantEntry(ROOT_PATH);
            special.putEntry(SPECIAL, driver.newEntry(ROOT_PATH, SPECIAL, entry));
            return special;
        }
    }
}