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Diffstat (limited to 'libjava/classpath/java/security/SecureClassLoader.java')
-rw-r--r-- | libjava/classpath/java/security/SecureClassLoader.java | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/libjava/classpath/java/security/SecureClassLoader.java b/libjava/classpath/java/security/SecureClassLoader.java new file mode 100644 index 0000000..9d1fac79 --- /dev/null +++ b/libjava/classpath/java/security/SecureClassLoader.java @@ -0,0 +1,128 @@ +/* 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., 51 Franklin Street, Fifth Floor, Boston, MA +02110-1301 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); + } +} |