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
   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.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 }