obfuz/Editor/MethodBodyObfuscationPassBa...

76 lines
2.9 KiB
C#

using dnlib.DotNet.Emit;
using dnlib.DotNet;
using System.Collections.Generic;
using System.Linq;
namespace Obfuz
{
public abstract class MethodBodyObfuscationPassBase : ObfuscationPassBase
{
protected abstract bool NeedObfuscateMethod(MethodDef method);
public override void Process(ObfuscatorContext ctx)
{
foreach (ModuleDef mod in ctx.toObfuscatedModules)
{
// ToArray to avoid modify list exception
foreach (TypeDef type in mod.GetTypes().ToArray())
{
if (type.Name.StartsWith("$Obfuz$"))
{
continue;
}
// ToArray to avoid modify list exception
foreach (MethodDef method in type.Methods.ToArray())
{
if (!method.HasBody || method.Name.StartsWith("$Obfuz$") || !NeedObfuscateMethod(method))
{
continue;
}
// TODO if isGeneratedBy Obfuscator, continue
ObfuscateData(method);
}
}
}
}
protected abstract bool TryObfuscateInstruction(MethodDef callingMethod, Instruction inst, IList<Instruction> instructions, int instructionIndex,
List<Instruction> outputInstructions, List<Instruction> totalFinalInstructions);
private void ObfuscateData(MethodDef method)
{
IList<Instruction> instructions = method.Body.Instructions;
var outputInstructions = new List<Instruction>();
var totalFinalInstructions = new List<Instruction>();
for (int i = 0; i < instructions.Count; i++)
{
Instruction inst = instructions[i];
outputInstructions.Clear();
if (TryObfuscateInstruction(method, inst, instructions, i, outputInstructions, totalFinalInstructions))
{
// current instruction may be the target of control flow instruction, so we can't remove it directly.
// we replace it with nop now, then remove it in CleanUpInstructionPass
inst.OpCode = outputInstructions[0].OpCode;
inst.Operand = outputInstructions[0].Operand;
totalFinalInstructions.Add(inst);
for (int k = 1; k < outputInstructions.Count; k++)
{
totalFinalInstructions.Add(outputInstructions[k]);
}
}
else
{
totalFinalInstructions.Add(inst);
}
}
instructions.Clear();
foreach (var obInst in totalFinalInstructions)
{
instructions.Add(obInst);
}
}
}
}