/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Rhino code, released May 6, 1999.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1997-1999
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* the GNU General Public License Version 2 or later (the "GPL"), in which
* case the provisions of the GPL are applicable instead of those above. If
* you wish to allow use of your version of this file only under the terms of
* the GPL and not to allow others to use your version of this file under the
* MPL, indicate your decision by deleting the provisions above and replacing
* them with the notice and other provisions required by the GPL. If you do
* not delete the provisions above, a recipient may use your version of this
* file under either the MPL or the GPL.
*
* ***** END LICENSE BLOCK ***** */
package org.mozilla.javascript;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.lang.ref.SoftReference;
import java.lang.reflect.UndeclaredThrowableException;
import java.net.URL;
import java.security.AccessController;
import java.security.CodeSource;
import java.security.PrivilegedAction;
import java.security.PrivilegedActionException;
import java.security.PrivilegedExceptionAction;
import java.security.SecureClassLoader;
import java.util.Map;
import java.util.WeakHashMap;
/**
* @author Attila Szegedi
*/
public abstract class SecureCaller
{
private static final byte[] secureCallerImplBytecode = loadBytecode();
// We're storing a CodeSource -> (ClassLoader -> SecureRenderer), since we
// need to have one renderer per class loader. We're using weak hash maps
// and soft references all the way, since we don't want to interfere with
// cleanup of either CodeSource or ClassLoader objects.
private static final Map callers = new WeakHashMap();
public abstract Object call(Callable callable, Context cx,
Scriptable scope, Scriptable thisObj, Object[] args);
/**
* Call the specified callable using a protection domain belonging to the
* specified code source.
*/
static Object callSecurely(final CodeSource codeSource, Callable callable,
Context cx, Scriptable scope, Scriptable thisObj, Object[] args)
{
final Thread thread = Thread.currentThread();
// Run in doPrivileged as we might be checked for "getClassLoader"
// runtime permission
final ClassLoader classLoader = (ClassLoader)AccessController.doPrivileged(
new PrivilegedAction() {
public Object run() {
return thread.getContextClassLoader();
}
});
Map classLoaderMap;
synchronized(callers)
{
classLoaderMap = (Map)callers.get(codeSource);
if(classLoaderMap == null)
{
classLoaderMap = new WeakHashMap();
callers.put(codeSource, classLoaderMap);
}
}
SecureCaller caller;
synchronized(classLoaderMap)
{
SoftReference ref = (SoftReference)classLoaderMap.get(classLoader);
if(ref != null)
{
caller = (SecureCaller)ref.get();
}
else
{
caller = null;
}
if(caller == null)
{
try
{
// Run in doPrivileged as we'll be checked for
// "createClassLoader" runtime permission
caller = (SecureCaller)AccessController.doPrivileged(
new PrivilegedExceptionAction()
{
public Object run() throws Exception
{
ClassLoader effectiveClassLoader;
Class thisClass = getClass();
if(classLoader.loadClass(thisClass.getName()) != thisClass) {
effectiveClassLoader = thisClass.getClassLoader();
} else {
effectiveClassLoader = classLoader;
}
SecureClassLoaderImpl secCl =
new SecureClassLoaderImpl(effectiveClassLoader);
Class c = secCl.defineAndLinkClass(
SecureCaller.class.getName() + "Impl",
secureCallerImplBytecode, codeSource);
return c.newInstance();
}
});
classLoaderMap.put(classLoader, new SoftReference(caller));
}
catch(PrivilegedActionException ex)
{
throw new UndeclaredThrowableException(ex.getCause());
}
}
}
return caller.call(callable, cx, scope, thisObj, args);
}
private static class SecureClassLoaderImpl extends SecureClassLoader
{
SecureClassLoaderImpl(ClassLoader parent)
{
super(parent);
}
Class defineAndLinkClass(String name, byte[] bytes, CodeSource cs)
{
Class cl = defineClass(name, bytes, 0, bytes.length, cs);
resolveClass(cl);
return cl;
}
}
private static byte[] loadBytecode()
{
return (byte[])AccessController.doPrivileged(new PrivilegedAction()
{
public Object run()
{
return loadBytecodePrivileged();
}
});
}
private static byte[] loadBytecodePrivileged()
{
URL url = SecureCaller.class.getResource("SecureCallerImpl.clazz");
try
{
InputStream in = url.openStream();
try
{
ByteArrayOutputStream bout = new ByteArrayOutputStream();
for(;;)
{
int r = in.read();
if(r == -1)
{
return bout.toByteArray();
}
bout.write(r);
}
}
finally
{
in.close();
}
}
catch(IOException e)
{
throw new UndeclaredThrowableException(e);
}
}
}
