/*
Copyright (C) 2011-2012 de4dot@gmail.com
This file is part of de4dot.
de4dot is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
de4dot 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 for more details.
You should have received a copy of the GNU General Public License
along with de4dot. If not, see .
*/
using System;
using System.Collections.Generic;
using dot10.DotNet;
using dot10.DotNet.Emit;
using de4dot.blocks;
namespace de4dot.code.deobfuscators {
abstract class ValueInlinerBase : MethodReturnValueInliner {
MethodDefAndDeclaringTypeDict> decrypterMethods = new MethodDefAndDeclaringTypeDict>();
bool removeUnbox = false;
class MyCallResult : CallResult {
public IMethod methodRef;
public MethodSpec gim;
public MyCallResult(Block block, int callEndIndex, IMethod method, MethodSpec gim)
: base(block, callEndIndex) {
this.methodRef = method;
this.gim = gim;
}
}
public bool RemoveUnbox {
get { return removeUnbox; }
set { removeUnbox = value; }
}
public override bool HasHandlers {
get { return decrypterMethods.Count != 0; }
}
public IEnumerable Methods {
get { return decrypterMethods.getKeys(); }
}
public void add(MethodDef method, Func handler) {
if (method == null)
return;
if (decrypterMethods.find(method) != null)
throw new ApplicationException(string.Format("Handler for method {0:X8} has already been added", method.MDToken.ToInt32()));
if (method != null)
decrypterMethods.add(method, handler);
}
protected override void inlineAllCalls() {
foreach (var tmp in callResults) {
var callResult = (MyCallResult)tmp;
var handler = decrypterMethods.find(callResult.methodRef);
callResult.returnValue = handler((MethodDef)callResult.methodRef, callResult.gim, callResult.args);
}
}
protected override CallResult createCallResult(IMethod method, MethodSpec gim, Block block, int callInstrIndex) {
if (decrypterMethods.find(method) == null)
return null;
return new MyCallResult(block, callInstrIndex, method, gim);
}
protected bool removeUnboxInstruction(Block block, int index, string unboxType) {
if (!removeUnbox)
return false;
var instrs = block.Instructions;
if (index >= instrs.Count)
return false;
var unbox = instrs[index];
if (unbox.OpCode.Code != Code.Unbox_Any)
return false;
var type = unbox.Operand as ITypeDefOrRef;
if (type == null || type.FullName != unboxType)
return false;
block.remove(index, 1);
return true;
}
}
class BooleanValueInliner : ValueInlinerBase {
protected override void inlineReturnValues(IList callResults) {
foreach (var callResult in callResults) {
var block = callResult.block;
int num = callResult.callEndIndex - callResult.callStartIndex + 1;
block.replace(callResult.callStartIndex, num, Instruction.CreateLdcI4((bool)callResult.returnValue ? 1 : 0));
removeUnboxInstruction(block, callResult.callStartIndex + 1, "System.Boolean");
Logger.v("Decrypted boolean: {0}", callResult.returnValue);
}
}
}
class Int32ValueInliner : ValueInlinerBase {
protected override void inlineReturnValues(IList callResults) {
foreach (var callResult in callResults) {
var block = callResult.block;
int num = callResult.callEndIndex - callResult.callStartIndex + 1;
block.replace(callResult.callStartIndex, num, Instruction.CreateLdcI4((int)callResult.returnValue));
removeUnboxInstruction(block, callResult.callStartIndex + 1, "System.Int32");
Logger.v("Decrypted int32: {0}", callResult.returnValue);
}
}
}
class Int64ValueInliner : ValueInlinerBase {
protected override void inlineReturnValues(IList callResults) {
foreach (var callResult in callResults) {
var block = callResult.block;
int num = callResult.callEndIndex - callResult.callStartIndex + 1;
block.replace(callResult.callStartIndex, num, OpCodes.Ldc_I8.ToInstruction((long)callResult.returnValue));
removeUnboxInstruction(block, callResult.callStartIndex + 1, "System.Int64");
Logger.v("Decrypted int64: {0}", callResult.returnValue);
}
}
}
class SingleValueInliner : ValueInlinerBase {
protected override void inlineReturnValues(IList callResults) {
foreach (var callResult in callResults) {
var block = callResult.block;
int num = callResult.callEndIndex - callResult.callStartIndex + 1;
block.replace(callResult.callStartIndex, num, OpCodes.Ldc_R4.ToInstruction((float)callResult.returnValue));
removeUnboxInstruction(block, callResult.callStartIndex + 1, "System.Single");
Logger.v("Decrypted single: {0}", callResult.returnValue);
}
}
}
class DoubleValueInliner : ValueInlinerBase {
protected override void inlineReturnValues(IList callResults) {
foreach (var callResult in callResults) {
var block = callResult.block;
int num = callResult.callEndIndex - callResult.callStartIndex + 1;
block.replace(callResult.callStartIndex, num, OpCodes.Ldc_R8.ToInstruction((double)callResult.returnValue));
removeUnboxInstruction(block, callResult.callStartIndex + 1, "System.Double");
Logger.v("Decrypted double: {0}", callResult.returnValue);
}
}
}
}