1 /* SecureClassLoader.java --- A Secure Class Loader 2 Copyright (C) 1999 Free Software Foundation, Inc. 3 4 This file is part of GNU Classpath. 5 6 GNU Classpath is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2, or (at your option) 9 any later version. 10 11 GNU Classpath is distributed in the hope that it will be useful, but 12 WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GNU Classpath; see the file COPYING. If not, write to the 18 Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 19 02111-1307 USA. 20 21 Linking this library statically or dynamically with other modules is 22 making a combined work based on this library. Thus, the terms and 23 conditions of the GNU General Public License cover the whole 24 combination. 25 26 As a special exception, the copyright holders of this library give you 27 permission to link this library with independent modules to produce an 28 executable, regardless of the license terms of these independent 29 modules, and to copy and distribute the resulting executable under 30 terms of your choice, provided that you also meet, for each linked 31 independent module, the terms and conditions of the license of that 32 module. An independent module is a module which is not derived from 33 or based on this library. If you modify this library, you may extend 34 this exception to your version of the library, but you are not 35 obligated to do so. If you do not wish to do so, delete this 36 exception statement from your version. */ 37 38 package java.security; 39 40 /** 41 A Secure Class Loader for loading classes with additional 42 support for specifying code source and permissions when 43 they are retrieved by the system policy handler. 44 45 @since JDK 1.2 46 47 @author Mark Benvenuto 48 */ 49 public class SecureClassLoader extends ClassLoader 50 { SecureClassLoader(ClassLoader parent)51 protected SecureClassLoader(ClassLoader parent) 52 { 53 super(parent); 54 SecurityManager sm = System.getSecurityManager(); 55 if(sm != null) 56 sm.checkCreateClassLoader(); 57 } 58 SecureClassLoader()59 protected SecureClassLoader() 60 { 61 SecurityManager sm = System.getSecurityManager(); 62 if(sm != null) 63 sm.checkCreateClassLoader(); 64 } 65 66 /** 67 Creates a class using an array of bytes and a 68 CodeSource. 69 70 @param name the name to give the class. null if unknown. 71 @param b the data representing the classfile, in classfile format. 72 @param off the offset into the data where the classfile starts. 73 @param len the length of the classfile data in the array. 74 @param cs the CodeSource for the class or null when unknown. 75 76 @return the class that was defined and optional CodeSource. 77 78 @exception ClassFormatError if the byte array is not in proper classfile format. 79 */ defineClass(String name, byte[] b, int off, int len, CodeSource cs)80 protected final Class defineClass(String name, byte[] b, int off, int len, 81 CodeSource cs) 82 { 83 // FIXME: Need to cache ProtectionDomains according to 1.3 docs. 84 if (cs != null) 85 { 86 ProtectionDomain protectionDomain 87 = new ProtectionDomain(cs, getPermissions(cs)); 88 return super.defineClass(name, b, off, len, protectionDomain); 89 } 90 else 91 return super.defineClass(name, b, off, len); 92 } 93 94 /** 95 Returns a PermissionCollection for the specified CodeSource. 96 The default implementation invokes 97 java.security.Policy.getPermissions. 98 99 This method is called by defineClass that takes a CodeSource 100 arguement to build a proper ProtectionDomain for the class 101 being defined. 102 103 */ getPermissions(CodeSource cs)104 protected PermissionCollection getPermissions(CodeSource cs) 105 { 106 Policy policy = Policy.getPolicy(); 107 return policy.getPermissions(cs); 108 } 109 } 110