| /* SecureClassLoader.java --- A Secure Class Loader |
| Copyright (C) 1999, 2004 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath 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 for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| package java.security; |
| |
| /** |
| * A Secure Class Loader for loading classes with additional |
| * support for specifying code source and permissions when |
| * they are retrieved by the system policy handler. |
| * |
| * @since 1.2 |
| * |
| * @author Mark Benvenuto |
| */ |
| public class SecureClassLoader extends ClassLoader |
| { |
| java.util.WeakHashMap protectionDomainCache = new java.util.WeakHashMap(); |
| |
| protected SecureClassLoader(ClassLoader parent) |
| { |
| super(parent); |
| SecurityManager sm = System.getSecurityManager(); |
| if(sm != null) |
| sm.checkCreateClassLoader(); |
| } |
| |
| protected SecureClassLoader() |
| { |
| SecurityManager sm = System.getSecurityManager(); |
| if(sm != null) |
| sm.checkCreateClassLoader(); |
| } |
| |
| /** |
| * Creates a class using an array of bytes and a |
| * CodeSource. |
| * |
| * @param name the name to give the class. null if unknown. |
| * @param b the data representing the classfile, in classfile format. |
| * @param off the offset into the data where the classfile starts. |
| * @param len the length of the classfile data in the array. |
| * @param cs the CodeSource for the class or null when unknown. |
| * |
| * @return the class that was defined and optional CodeSource. |
| * |
| * @exception ClassFormatError if the byte array is not in proper classfile format. |
| */ |
| protected final Class defineClass(String name, byte[] b, int off, int len, |
| CodeSource cs) |
| { |
| if (cs != null) |
| { |
| ProtectionDomain protectionDomain; |
| |
| synchronized (protectionDomainCache) |
| { |
| protectionDomain = (ProtectionDomain)protectionDomainCache.get(cs); |
| } |
| |
| if (protectionDomain == null) |
| { |
| protectionDomain |
| = new ProtectionDomain(cs, getPermissions(cs), this, null); |
| synchronized (protectionDomainCache) |
| { |
| ProtectionDomain domain |
| = (ProtectionDomain)protectionDomainCache.get(cs); |
| if (domain == null) |
| protectionDomainCache.put(cs, protectionDomain); |
| else |
| protectionDomain = domain; |
| } |
| } |
| return super.defineClass(name, b, off, len, protectionDomain); |
| } |
| else |
| return super.defineClass(name, b, off, len); |
| } |
| |
| /** |
| * Returns a PermissionCollection for the specified CodeSource. |
| * The default implementation invokes |
| * java.security.Policy.getPermissions. |
| * |
| * This method is called by defineClass that takes a CodeSource |
| * arguement to build a proper ProtectionDomain for the class |
| * being defined. |
| */ |
| protected PermissionCollection getPermissions(CodeSource cs) |
| { |
| Policy policy = Policy.getCurrentPolicy(); |
| return policy.getPermissions(cs); |
| } |
| } |