/*

 * Copyright (c) 1999, 2020, Oracle and/or its affiliates. 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.  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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package com.sun.jndi.ldap;

import java.net.URLClassLoader;

import java.net.MalformedURLException;

import java.security.AccessControlContext;

import java.security.AccessController;

import java.security.PrivilegedAction;

import sun.misc.SharedSecrets;

final class VersionHelper12 extends VersionHelper {

    // System property to control whether classes may be loaded from an

    // arbitrary URL code base.

    private static final String TRUST_URL_CODEBASE_PROPERTY =

        "com.sun.jndi.ldap.object.trustURLCodebase";

    // System property to control whether classes are allowed to be loaded from

    // 'javaSerializedData' attribute

    private static final String TRUST_SERIAL_DATA_PROPERTY =

        "com.sun.jndi.ldap.object.trustSerialData";

    /**

     * Determines whether objects may be deserialized from the content of

     * 'javaSerializedData' attribute.

     */

    private static final boolean trustSerialData;

    // Determine whether classes may be loaded from an arbitrary URL code base.

    private static final boolean trustURLCodebase;

    static {

        String trust = getPrivilegedProperty(TRUST_URL_CODEBASE_PROPERTY, "false");

        trustURLCodebase = "true".equalsIgnoreCase(trust);

        String trustSDString = getPrivilegedProperty(TRUST_SERIAL_DATA_PROPERTY, "true");

        trustSerialData = "true".equalsIgnoreCase(trustSDString);

    }

    private static String getPrivilegedProperty(String propertyName, String defaultVal) {

        PrivilegedAction<String> action = () -> System.getProperty(propertyName, defaultVal);

        if (System.getSecurityManager() == null) {

            return action.run();

        } else {

            return AccessController.doPrivileged(action);

        }

    }

    VersionHelper12() {} // Disallow external from creating one of these.

    /**

     * Returns true if deserialization of objects from 'javaSerializedData'

     * LDAP attribute is allowed.

     *

     * @return true if deserialization is allowed; false - otherwise

     */

    public static boolean isSerialDataAllowed() {

        return trustSerialData;

    }

    ClassLoader getURLClassLoader(String[] url)

        throws MalformedURLException {

            ClassLoader parent = getContextClassLoader();

            /*

             * Classes may only be loaded from an arbitrary URL code base when

             * the system property com.sun.jndi.ldap.object.trustURLCodebase

             * has been set to "true".

             */

            if (url != null && trustURLCodebase) {

                return URLClassLoader.newInstance(getUrlArray(url), parent);

            } else {

                return parent;

            }

    }

    Class<?> loadClass(String className) throws ClassNotFoundException {

        ClassLoader cl = getContextClassLoader();

        return Class.forName(className, true, cl);

    }

    private ClassLoader getContextClassLoader() {

        return AccessController.doPrivileged(

            new PrivilegedAction<ClassLoader>() {

                public ClassLoader run() {

                    return Thread.currentThread().getContextClassLoader();

                }

            }

        );

    }

    Thread createThread(final Runnable r) {

        final AccessControlContext acc = AccessController.getContext();

        // 4290486: doPrivileged is needed to create a thread in

        // an environment that restricts "modifyThreadGroup".

        return AccessController.doPrivileged(

                new PrivilegedAction<Thread>() {

                    public Thread run() {

                        return SharedSecrets.getJavaLangAccess()

                                .newThreadWithAcc(r, acc);

                    }

                }

        );

    }

}