1 /*

     2  * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

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

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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

    23  * questions.

    24  */

    25 

    26 package com.sun.jndi.ldap;

    27 

    28 import java.net.URLClassLoader;

    29 import java.net.MalformedURLException;

    30 import java.security.AccessControlContext;

    31 import java.security.AccessController;

    32 import java.security.PrivilegedAction;

    33 import sun.misc.SharedSecrets;

    34 

    35 final class VersionHelper12 extends VersionHelper {

    36 

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

    38     // arbitrary URL code base.

    39     private static final String TRUST_URL_CODEBASE_PROPERTY =

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

    41 

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

    43     private static final String trustURLCodebase =

    44         AccessController.doPrivileged(

    45             new PrivilegedAction<String>() {

    46                 public String run() {

    47                     return System.getProperty(TRUST_URL_CODEBASE_PROPERTY,

    48                             "false");

    49                 }

    50             }

    51         );

    52 

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

    54 

    55     ClassLoader getURLClassLoader(String[] url)

    56         throws MalformedURLException {

    57             ClassLoader parent = getContextClassLoader();

    58             /*

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

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

    61              * has been set to "true".

    62              */

    63             if (url != null && "true".equalsIgnoreCase(trustURLCodebase)) {

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

    65             } else {

    66                 return parent;

    67             }

    68     }

    69 

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

    71         ClassLoader cl = getContextClassLoader();

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

    73     }

    74 

    75     private ClassLoader getContextClassLoader() {

    76         return AccessController.doPrivileged(

    77             new PrivilegedAction<ClassLoader>() {

    78                 public ClassLoader run() {

    79                     return Thread.currentThread().getContextClassLoader();

    80                 }

    81             }

    82         );

    83     }

    84 

    85     Thread createThread(final Runnable r) {

    86         final AccessControlContext acc = AccessController.getContext();

    87         // 4290486: doPrivileged is needed to create a thread in

    88         // an environment that restricts "modifyThreadGroup".

    89         return AccessController.doPrivileged(

    90                 new PrivilegedAction<Thread>() {

    91                     public Thread run() {

    92                         return SharedSecrets.getJavaLangAccess()

    93                                 .newThreadWithAcc(r, acc);

    94                     }

    95                 }

    96         );

    97     }

    98 }