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The file system driver family for ZIP and related archive file types. 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) 2005-2013 Schlichtherle IT Services.
 * All rights reserved. Use is subject to license terms.
 */
package de.schlichtherle.truezip.key.pbe.console;

import de.schlichtherle.truezip.crypto.param.KeyStrength;
import de.schlichtherle.truezip.key.KeyPromptingDisabledException;
import de.schlichtherle.truezip.key.PromptingKeyProvider.Controller;
import de.schlichtherle.truezip.key.pbe.SafePbeParameters;
import de.schlichtherle.truezip.key.pbe.SafePbeParametersView;
import java.io.Console;
import java.io.PrintWriter;
import java.net.URI;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.ResourceBundle;
import javax.annotation.concurrent.ThreadSafe;

/**
 * A console based user interface to prompt for passwords.
 * 
 * @author  Christian Schlichtherle
 */
@ThreadSafe
public abstract class ConsoleSafePbeParametersView<
        S extends KeyStrength,
        P extends SafePbeParameters>
extends SafePbeParametersView {

    private static final ResourceBundle
            resources = ResourceBundle.getBundle(
                ConsoleSafePbeParametersView.class.getName());

    /**
     * Used to lock out prompting by multiple threads.
     */
    private static final PromptingLock lock = new PromptingLock();

    /** The minimum acceptable length of a password. */
    private static final int MIN_PASSWD_LEN = 8;

    /**
     * The last resource ID used when prompting.
     * Initialized to the empty string.
     */
    @edu.umd.cs.findbugs.annotations.SuppressWarnings("ST_WRITE_TO_STATIC_FROM_INSTANCE_METHOD")
    private static URI lastResource = URI.create(""); // NOI18N
    
    private static final String YES = resources.getString("yes");
    private static final String NO = resources.getString("no");

    @Override
    public final void promptWriteKey(final Controller
 controller)
    throws KeyPromptingDisabledException {
        final Console con = System.console();
        if (null == con)
            throw new KeyPromptingDisabledException();

        synchronized (lock) {
            final URI resource = controller.getResource();
            assert null != resource;
            if (!lastResource.equals(resource))
                con.printf(resources.getString("writeKey.banner"), resource);
            lastResource = resource;

            P param = controller.getKey();
            if (null == param)
                param = newPbeParameters();

            while (true) {
                char[] input1 = con.readPassword(
                        resources.getString("writeKey.newPasswd1"));
                if (null == input1 || 0 >= input1.length)
                    return;
                if (MIN_PASSWD_LEN > input1.length) {
                    con.printf(resources.getString("writeKey.passwd.tooShort"), MIN_PASSWD_LEN);
                    continue;
                }
                try {
                    char[] input2 = con.readPassword(
                            resources.getString("writeKey.newPasswd2"));
                    if (input2 == null)
                        return;
                    try {
                        if (!Arrays.equals(input1, input2)) {
                            con.printf(resources.getString("writeKey.passwd.noMatch"));
                            continue;
                        }
                        param.setPassword(input1);
                        break;
                    } finally {
                        Arrays.fill(input2, (char) 0);
                    }
                }  finally {
                    Arrays.fill(input1, (char) 0);
                }
            }

            con.printf(resources.getString("keyStrength.banner"));
            final String selection;
            final Map map;
            {
                final StringBuilder builder = new StringBuilder();
                final S[] array = param.getKeyStrengthValues();
                map = new HashMap(array.length / 3 * 4 + 1);
                final PrintWriter writer = con.writer();
                for (final S strength : array) {
                    if (0 < builder.length())
                        builder.append('/');
                    builder.append(strength.getBits());
                    map.put(strength.getBits(), strength);
                    writer.println(strength);
                }
                selection = builder.toString();
            }

            while (true) {
                String input = con.readLine(
                        resources.getString("keyStrength.prompt"),
                        selection,
                        param.getKeyStrength().getBits());
                if (null == input || input.length() <= 0)
                    break;
                try {
                    final int bits = Integer.parseInt(input);
                    final S strength = map.get(bits);
                    if (null != strength) {
                        assert strength.getBits() == bits;
                        param.setKeyStrength(strength);
                        break;
                    }
                } catch (NumberFormatException ex) {
                }
            }

            controller.setKey(param);
        }
    }

    @Override
    public void promptReadKey(
            final Controller controller,
            final boolean invalid)
    throws KeyPromptingDisabledException {
        final Console con = System.console();
        if (null == con)
            throw new KeyPromptingDisabledException();

        synchronized (lock) {
            if (invalid)
                con.printf(resources.getString("readKey.invalid"));

            final URI resource = controller.getResource();
            assert null != resource;
            if (!lastResource.equals(resource))
                con.printf(resources.getString("readKey.banner"), resource);
            lastResource = resource;

            final char[] passwd = con.readPassword(resources.getString("readKey.passwd"));
            if (null == passwd || passwd.length <= 0) {
                controller.setKey(null);
                return;
            }

            final P param = newPbeParameters();
            param.setPassword(passwd);
            Arrays.fill(passwd, (char) 0);
            controller.setKey(param);

            while (true) {
                String changeKey = con.readLine(resources.getString("readKey.change"));
                controller.setChangeRequested(YES.equalsIgnoreCase(changeKey));
                if (       null == changeKey
                        || changeKey.length() <= 0
                        || YES.equalsIgnoreCase(changeKey)
                        || NO.equalsIgnoreCase(changeKey))
                    return;
            }
        }
    }

    /** Used to lock out concurrent prompting. */
    private static class PromptingLock {
    }
}