1   /*
2    * Copyright (c) 2005, 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
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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.
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24   */
25  
26  package com.sun.script.javascript;
27  
28  import java.util.*;
29  import sun.org.mozilla.javascript.internal.*;
30  
31  /**
32   * This class prevents script access to certain sensitive classes.
33   * Note that this class checks over and above SecurityManager. i.e., although
34   * a SecurityManager would pass, class shutter may still prevent access.
35   *
36   * @author A. Sundararajan
37   * @since 1.6
38   */
39  final class RhinoClassShutter implements ClassShutter {
40      private static Map<String, Boolean> protectedClasses;
41      private static RhinoClassShutter theInstance;
42  
43      private RhinoClassShutter() {
44      }
45  
46      static synchronized ClassShutter getInstance() {
47          if (theInstance == null) {
48              theInstance = new RhinoClassShutter();
49              protectedClasses = new HashMap<String, Boolean>();
50  
51              // For now, we just have AccessController. Allowing scripts
52              // to this class will allow it to execute doPrivileged in
53              // bootstrap context. We can add more classes for other reasons.
54              protectedClasses.put("java.security.AccessController", Boolean.TRUE);
55          }
56          return theInstance;
57      }
58  
59      public boolean visibleToScripts(String fullClassName) {
60          // first do the security check.
61          SecurityManager sm = System.getSecurityManager();
62          if (sm != null) {
63              int i = fullClassName.lastIndexOf(".");
64              if (i != -1) {
65                  try {
66                      sm.checkPackageAccess(fullClassName.substring(0, i));
67                  } catch (SecurityException se) {
68                      return false;
69                  }
70              }
71          }
72          // now, check is it a protected class.
73          return protectedClasses.get(fullClassName) == null;
74      }
75  }