| /* |
| * Copyright (c) 2010, 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code 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 |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package jdk.nashorn.internal.runtime.linker; |
| |
| import java.security.AccessControlContext; |
| import java.security.AccessController; |
| import java.security.PrivilegedAction; |
| import java.security.ProtectionDomain; |
| import java.security.SecureClassLoader; |
| import java.util.Arrays; |
| import java.util.Collection; |
| import java.util.Collections; |
| import java.util.HashSet; |
| import jdk.internal.dynalink.beans.StaticClass; |
| import jdk.nashorn.internal.codegen.DumpBytecode; |
| import jdk.nashorn.internal.runtime.Context; |
| import jdk.nashorn.internal.runtime.JSType; |
| import jdk.nashorn.internal.runtime.ScriptFunction; |
| import jdk.nashorn.internal.runtime.ScriptObject; |
| |
| /** |
| * This class encapsulates the bytecode of the adapter class and can be used to load it into the JVM as an actual Class. |
| * It can be invoked repeatedly to create multiple adapter classes from the same bytecode; adapter classes that have |
| * class-level overrides must be re-created for every set of such overrides. Note that while this class is named |
| * "class loader", it does not, in fact, extend {@code ClassLoader}, but rather uses them internally. Instances of this |
| * class are normally created by {@code JavaAdapterBytecodeGenerator}. |
| */ |
| final class JavaAdapterClassLoader { |
| private static final AccessControlContext CREATE_LOADER_ACC_CTXT = ClassAndLoader.createPermAccCtxt("createClassLoader"); |
| private static final AccessControlContext GET_CONTEXT_ACC_CTXT = ClassAndLoader.createPermAccCtxt(Context.NASHORN_GET_CONTEXT); |
| private static final Collection<String> VISIBLE_INTERNAL_CLASS_NAMES = Collections.unmodifiableCollection(new HashSet<>( |
| Arrays.asList(JavaAdapterServices.class.getName(), ScriptObject.class.getName(), ScriptFunction.class.getName(), JSType.class.getName()))); |
| |
| private final String className; |
| private final byte[] classBytes; |
| |
| JavaAdapterClassLoader(final String className, final byte[] classBytes) { |
| this.className = className.replace('/', '.'); |
| this.classBytes = classBytes; |
| } |
| |
| /** |
| * Loads the generated adapter class into the JVM. |
| * @param parentLoader the parent class loader for the generated class loader |
| * @param protectionDomain the protection domain for the generated class |
| * @return the generated adapter class |
| */ |
| StaticClass generateClass(final ClassLoader parentLoader, final ProtectionDomain protectionDomain) { |
| assert protectionDomain != null; |
| return AccessController.doPrivileged(new PrivilegedAction<StaticClass>() { |
| @Override |
| public StaticClass run() { |
| try { |
| return StaticClass.forClass(Class.forName(className, true, createClassLoader(parentLoader, protectionDomain))); |
| } catch (final ClassNotFoundException e) { |
| throw new AssertionError(e); // cannot happen |
| } |
| } |
| }, CREATE_LOADER_ACC_CTXT); |
| } |
| |
| // Note that the adapter class is created in the protection domain of the class/interface being |
| // extended/implemented, and only the privileged global setter action class is generated in the protection domain |
| // of Nashorn itself. Also note that the creation and loading of the global setter is deferred until it is |
| // required by JVM linker, which will only happen on first invocation of any of the adapted method. We could defer |
| // it even more by separating its invocation into a separate static method on the adapter class, but then someone |
| // with ability to introspect on the class and use setAccessible(true) on it could invoke the method. It's a |
| // security tradeoff... |
| private ClassLoader createClassLoader(final ClassLoader parentLoader, final ProtectionDomain protectionDomain) { |
| return new SecureClassLoader(parentLoader) { |
| private final ClassLoader myLoader = getClass().getClassLoader(); |
| |
| @Override |
| public Class<?> loadClass(final String name, final boolean resolve) throws ClassNotFoundException { |
| try { |
| Context.checkPackageAccess(name); |
| return super.loadClass(name, resolve); |
| } catch (final SecurityException se) { |
| // we may be implementing an interface or extending a class that was |
| // loaded by a loader that prevents package.access. If so, it'd throw |
| // SecurityException for nashorn's classes!. For adapter's to work, we |
| // should be able to refer to the few classes it needs in its implementation. |
| if(VISIBLE_INTERNAL_CLASS_NAMES.contains(name)) { |
| return myLoader.loadClass(name); |
| } |
| throw se; |
| } |
| } |
| |
| @Override |
| protected Class<?> findClass(final String name) throws ClassNotFoundException { |
| if(name.equals(className)) { |
| assert classBytes != null : "what? already cleared .class bytes!!"; |
| |
| final Context ctx = AccessController.doPrivileged(new PrivilegedAction<Context>() { |
| @Override |
| public Context run() { |
| return Context.getContext(); |
| } |
| }, GET_CONTEXT_ACC_CTXT); |
| DumpBytecode.dumpBytecode(ctx.getEnv(), ctx.getLogger(jdk.nashorn.internal.codegen.Compiler.class), classBytes, name); |
| return defineClass(name, classBytes, 0, classBytes.length, protectionDomain); |
| } |
| throw new ClassNotFoundException(name); |
| } |
| }; |
| } |
| } |