More execution work

src/main/java/info/sigterm/deob/attributes/code/instructions/AAStore.java

@@ -20,10 +20,13 @@ public class AAStore extends Instruction
 	{
 		Stack stack = frame.getStack();
 		
-		ObjectInstance value = (ObjectInstance) stack.pop(); // Strings are objects too, so this cast fails
+		Object value = stack.pop();
 		int index = (int) stack.pop();
 		ArrayInstance array = (ArrayInstance) stack.pop();
 		
+		if (array == null)
+			return;
+		
 		array.put(value, index);
 	}
 }

src/main/java/info/sigterm/deob/attributes/code/instructions/AStore.java

@@ -25,7 +25,6 @@ public class AStore extends Instruction
 	public void execute(Frame frame)
 	{
 		Object obj = frame.getStack().pop();
-		assert obj != null;
 		frame.getVariables().set(index, obj);
 	}
 }

src/main/java/info/sigterm/deob/attributes/code/instructions/InvokeSpecial.java

@@ -9,6 +9,7 @@ import info.sigterm.deob.execution.ClassInstance;
 import info.sigterm.deob.execution.Frame;
 import info.sigterm.deob.execution.ObjectInstance;
 import info.sigterm.deob.pool.Method;
+import info.sigterm.deob.pool.PoolEntry;
 
 import java.io.DataInputStream;
 import java.io.IOException;
@@ -36,15 +37,31 @@ public class InvokeSpecial extends Instruction
 		int count = method.getNameAndType().getNumberOfArgs();
 		
 		ObjectInstance object = (ObjectInstance) e.getStack().pop();
-		ClassInstance objectType = object.getType();
 		
 		Object[] args = new Object[count + 1];
 		args[0] = object;
 		for (int i = 1; i < count + 1; ++i)
 			args[i] = e.getStack().pop();
 		
+		if (object == null)
+		{
+			System.out.println("invokespecial for nonexistant function " + method.getNameAndType().getName() + " " + method.getNameAndType().getDescriptor() + " on " + method.getClassEntry().getName() + " (void: " + !method.getNameAndType().isNonVoid() + ")");
+			if (method.getNameAndType().isNonVoid())
+				e.getStack().push(this, null);
+			return;
+		}
+		
+		ClassInstance objectType = object.getType();
 		info.sigterm.deob.Method meth = objectType.getClassFile().findMethod(method.getNameAndType());
 		e.getPath().invoke(meth, args);
 	}
 
+	@Override
+	public String getDesc(Frame frame)
+	{
+		ClassFile thisClass = this.getInstructions().getCode().getAttributes().getClassFile();
+		Method method = (Method) thisClass.getPool().getEntry(index);
+		
+		return "invokespecial " + method.getNameAndType().getDescriptor() + " on " + method.getClassEntry().getName();
+	}
 }

src/main/java/info/sigterm/deob/attributes/code/instructions/InvokeVirtual.java

@@ -42,7 +42,7 @@ public class InvokeVirtual extends Instruction
 		ObjectInstance object = (ObjectInstance) e.getStack().pop();
 		if (object == null)
 		{
-			System.out.println("Invoke on a null object");
+			System.out.println("invokevirtual on null object for method " + method.getNameAndType().getName() + " " + method.getNameAndType().getDescriptor() + " on " + method.getClassEntry().getName());
 			e.getStack().push(this, null);
 			return;
 		}
@@ -56,7 +56,6 @@ public class InvokeVirtual extends Instruction
 		{
 			System.out.println("Unknown method " + method.getNameAndType().getName() + " " + method.getNameAndType().getDescriptor() + " in " + objectType.getClassFile().getName());
 			e.getStack().push(this, null);
-			//meth.getDescriptor()
 			return;
 		}
 		e.getPath().invoke(meth, args);

src/main/java/info/sigterm/deob/execution/ArrayInstance.java

@@ -1,22 +1,30 @@
 package info.sigterm.deob.execution;
 
+import java.util.Arrays;
+
 
 public class ArrayInstance extends ObjectInstanceBase
 {
-	private ObjectInstance[] array;
+	private Object[] array;
 	
 	public ArrayInstance(Path path, ClassInstance type, int len)
 	{
 		super(path, type);
-		this.array = new ObjectInstance[len];
+		this.array = new Object[len];
 	}
 	
-	public void put(ObjectInstance obj, int idx)
+	private ArrayInstance(ArrayInstance other, Path path, ClassInstance type)
+	{
+		super(path, type);
+		this.array = Arrays.copyOf(other.array, other.array.length);
+	}
+	
+	public void put(Object obj, int idx)
 	{
 		array[idx] = obj;
 	}
 	
-	public ObjectInstance get(int idx)
+	public Object get(int idx)
 	{
 		return array[idx];
 	}
@@ -25,4 +33,10 @@ public class ArrayInstance extends ObjectInstanceBase
 	{
 		return array.length;
 	}
+
+	@Override
+	public ObjectInstanceBase dup(Path path, ClassInstance type)
+	{
+		return new ArrayInstance(this, path, type);
+	}
 }

src/main/java/info/sigterm/deob/execution/ClassInstance.java

@@ -33,6 +33,14 @@ public class ClassInstance
 				this.fields.add(fi);
 			}
 	}
+	
+	protected ClassInstance(Path path, ClassInstance other)
+	{
+		this.path = path;
+		this.clazz = other.clazz;
+		for (StaticFieldInstance f : other.fields)
+			this.fields.add(new StaticFieldInstance(other, f));
+	}
 
 	public Path getPath()
 	{

src/main/java/info/sigterm/deob/execution/FieldInstance.java

@@ -15,6 +15,13 @@ public class FieldInstance
 		this.value = value;
 	}
 	
+	protected FieldInstance(ObjectInstance object, FieldInstance other)
+	{
+		this.object = object;
+		this.field = other.field;
+		this.value = other.value;
+	}
+	
 	public Field getField()
 	{
 		return field;

src/main/java/info/sigterm/deob/execution/Frame.java

@@ -24,6 +24,16 @@ public class Frame
 		stack = new Stack(code.getMaxStack());
 		variables = new Variables(code.getMaxLocals());
 	}
+	
+	protected Frame(Path path, Frame other)
+	{
+		this.path = path;
+		this.method = other.method;
+		this.executing = other.executing;
+		this.pc = other.pc;
+		this.stack = new Stack(other.stack);
+		this.variables = new Variables(other.variables);
+	}
 
 	public Path getPath()
 	{
@@ -60,7 +70,20 @@ public class Frame
 			catch (Throwable ex)
 			{
 				System.err.println("Error executing instruction in " + method.getName() + " " + method.getDescriptor() + " in class " + method.getMethods().getClassFile().getName() + " at pc " + pc);
-				throw ex;
+				System.err.println("Frame stack (grows downward):");
+				while (stack.getSize() > 0)
+				{
+					Instruction stacki = stack.getIns();
+					Object obj = stack.pop();
+					if (obj != null)
+						System.err.println(" " + obj + " (class " + obj.getClass().getName() + ") pushed by instruction " + stacki + " at pc " + stacki.getPc());
+					else
+						System.err.println(" " + obj + " pushed by instruction " + stacki + " at pc " + stacki.getPc());
+				}
+				System.err.println("end of stack");
+				ex.printStackTrace();
+				System.exit(-1);
+				//throw ex;
 			}
 			
 			if (oldPc == pc)

src/main/java/info/sigterm/deob/execution/ObjectInstance.java

@@ -32,6 +32,15 @@ public class ObjectInstance extends ObjectInstanceBase
 		}
 	}
 	
+	private ObjectInstance(ObjectInstance other, Path path, ClassInstance type)
+	{
+		super(path, type);
+		
+		/* copy fields */
+		for (FieldInstance field : other.fields)
+			this.fields.add(new FieldInstance(this, field));
+	}
+	
 	public FieldInstance getField(NameAndType nat)
 	{
 		for (FieldInstance f : fields)
@@ -39,4 +48,10 @@ public class ObjectInstance extends ObjectInstanceBase
 				return f;
 		return null;
 	}
+
+	@Override
+	public ObjectInstanceBase dup(Path path, ClassInstance type)
+	{
+		return new ObjectInstance(this, path, type);
+	}
 }

src/main/java/info/sigterm/deob/execution/ObjectInstanceBase.java

@@ -16,4 +16,6 @@ public abstract class ObjectInstanceBase
 	{
 		return type;
 	}
+	
+	public abstract ObjectInstanceBase dup(Path path, ClassInstance type);
 }

src/main/java/info/sigterm/deob/execution/Path.java

@@ -5,12 +5,13 @@ import info.sigterm.deob.Method;
 import info.sigterm.deob.attributes.code.Instruction;
 
 import java.util.ArrayList;
+import java.util.HashMap;
 
 public class Path
 {
 	private Execution execution;
 	private ArrayList<ClassInstance> classes = new ArrayList<ClassInstance>();
-	private ArrayList<ObjectInstance> objects = new ArrayList<ObjectInstance>();
+	private ArrayList<ObjectInstanceBase> objects = new ArrayList<ObjectInstanceBase>();
 	private java.util.Stack<Frame> frames = new java.util.Stack<Frame>(); // current execution frames
 
 	public Path(Execution execution)
@@ -20,11 +21,23 @@ public class Path
 	
 	private Path(Path other)
 	{
+		HashMap<ClassInstance, ClassInstance> classmap = new HashMap<ClassInstance, ClassInstance>();
+		
 		this.execution = other.execution;
-		this.classes = new ArrayList<ClassInstance>(other.classes);
-		this.objects = new ArrayList<ObjectInstance>(other.objects);
-		this.frames = new java.util.Stack<Frame>();
-		this.frames.addAll(other.frames);
+		
+		for (ClassInstance c : other.classes)
+		{
+			ClassInstance newclass = new ClassInstance(this, c);
+			classmap.put(c,  newclass);
+			this.classes.add(newclass);
+		}
+		
+		for (ObjectInstanceBase o : other.objects)
+			o.dup(this, classmap.get(o.getType()));
+		
+		/* iteration order of a Stack is in reverse */
+		for (Frame f : other.frames)
+			frames.push(new Frame(this, f));
 	}
 
 	public Execution getExecution()
@@ -58,7 +71,9 @@ public class Path
 	
 	public ArrayInstance createArray(ClassInstance type, int len)
 	{
-		return new ArrayInstance(this, type, len);
+		ArrayInstance arr = new ArrayInstance(this, type, len);
+		objects.add(arr);
+		return arr;
 	}
 	
 	public Frame getCurrentFrame()
@@ -99,7 +114,7 @@ public class Path
 	
 	public void throwException(ObjectInstance exception)
 	{
-		System.out.println("throw " + exception);
+		System.out.println("XXX throw " + exception);
 		//XXX
 	}
 }

src/main/java/info/sigterm/deob/execution/Stack.java

@@ -1,5 +1,7 @@
 package info.sigterm.deob.execution;
 
+import java.util.Arrays;
+
 import info.sigterm.deob.attributes.code.Instruction;
 
 public class Stack
@@ -13,6 +15,13 @@ public class Stack
 		stack = new Object[sz];
 		ins = new Instruction[sz];
 	}
+	
+	protected Stack(Stack other)
+	{
+		this.size = other.size;
+		this.stack = Arrays.copyOf(other.stack, other.stack.length);
+		this.ins = Arrays.copyOf(other.ins, other.ins.length);
+	}
 
 	public void push(Instruction i, Object obj)
 	{
@@ -24,6 +33,14 @@ public class Stack
 		
 		++size;
 	}
+	
+	public Instruction getIns()
+	{
+		if (size <= 0)
+			throw new RuntimeException("Stack underflow");
+		
+		return ins[size - 1];
+	}
 
 	public Object pop()
 	{
@@ -32,4 +49,9 @@ public class Stack
 
 		return stack[--size];
 	}
+	
+	public int getSize()
+	{
+		return size;
+	}
 }

src/main/java/info/sigterm/deob/execution/StaticFieldInstance.java

@@ -16,6 +16,13 @@ public class StaticFieldInstance
 		if (value != null)
 			this.value = value.getValue().getObject();
 	}
+	
+	protected StaticFieldInstance(ClassInstance clazz, StaticFieldInstance other)
+	{
+		this.clazz = clazz;
+		this.field = other.field;
+		this.value = other.value;
+	}
 
 	public Field getField()
 	{

src/main/java/info/sigterm/deob/execution/Variables.java

@@ -1,5 +1,7 @@
 package info.sigterm.deob.execution;
 
+import java.util.Arrays;
+
 public class Variables
 {
 	private Object[] variables;
@@ -8,6 +10,11 @@ public class Variables
 	{
 		variables = new Object[sz];
 	}
+	
+	protected Variables(Variables other)
+	{
+		this.variables = Arrays.copyOf(other.variables, other.variables.length);
+	}
 
 	public void set(int index, Object value)
 	{

src/main/java/info/sigterm/deob/pool/NameAndType.java

@@ -79,4 +79,10 @@ public class NameAndType extends PoolEntry
 
 	    return count;
 	}
+	
+	public boolean isNonVoid()
+	{
+		java.lang.String methodRefType = this.getDescriptor();
+		return !methodRefType.endsWith(")V");
+	}
 }