97 lines
3.2 KiB
C#
97 lines
3.2 KiB
C#
|
using System;
|
||
|
|
using System.Collections.Generic;
|
||
|
|
using System.Linq;
|
||
|
|
using dnlib.DotNet;
|
||
|
|
using dnlib.DotNet.Emit;
|
||
|
|
|
||
|
|
namespace Obfuscator.Obfuscator.Mutation1;
|
||
|
|
|
||
|
|
internal class Mutation1
|
||
|
|
{
|
||
|
|
private static ModuleDefMD _moduleDefMd;
|
||
|
|
|
||
|
|
public static void Execute(ModuleDefMD moduleDefMd)
|
||
|
|
{
|
||
|
|
_moduleDefMd = moduleDefMd;
|
||
|
|
MutationHelper.CryptoRandom cryptoRandom = new MutationHelper.CryptoRandom();
|
||
|
|
foreach (TypeDef type in moduleDefMd.GetTypes())
|
||
|
|
{
|
||
|
|
List<MethodDef> list = new List<MethodDef>();
|
||
|
|
foreach (MethodDef item in type.Methods.Where((MethodDef x) => x.HasBody))
|
||
|
|
{
|
||
|
|
IList<Instruction> instructions = item.Body.Instructions;
|
||
|
|
for (int i = 0; i < instructions.Count; i++)
|
||
|
|
{
|
||
|
|
if (instructions[i].IsLdcI4() && IsSafe(instructions.ToList(), i))
|
||
|
|
{
|
||
|
|
MethodDef methodDef = null;
|
||
|
|
int ldcI4Value = instructions[i].GetLdcI4Value();
|
||
|
|
instructions[i].OpCode = OpCodes.Ldc_R8;
|
||
|
|
switch (cryptoRandom.Next(0, 3))
|
||
|
|
{
|
||
|
|
case 0:
|
||
|
|
methodDef = GenerateRefMethod("Floor");
|
||
|
|
instructions[i].Operand = Convert.ToDouble((double)ldcI4Value + cryptoRandom.NextDouble());
|
||
|
|
break;
|
||
|
|
case 1:
|
||
|
|
methodDef = GenerateRefMethod("Sqrt");
|
||
|
|
instructions[i].Operand = Math.Pow(Convert.ToDouble(ldcI4Value), 2.0);
|
||
|
|
break;
|
||
|
|
case 2:
|
||
|
|
methodDef = GenerateRefMethod("Round");
|
||
|
|
instructions[i].Operand = Convert.ToDouble(ldcI4Value);
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
instructions.Insert(i + 1, OpCodes.Call.ToInstruction(methodDef));
|
||
|
|
instructions.Insert(i + 2, OpCodes.Conv_I4.ToInstruction());
|
||
|
|
i += 2;
|
||
|
|
list.Add(methodDef);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
item.Body.SimplifyMacros(item.Parameters);
|
||
|
|
}
|
||
|
|
foreach (MethodDef item2 in list)
|
||
|
|
{
|
||
|
|
type.Methods.Add(item2);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
private static MethodDef GenerateRefMethod(string methodName)
|
||
|
|
{
|
||
|
|
MethodDefUser methodDefUser = new MethodDefUser("_" + Guid.NewGuid().ToString("D").ToUpper()
|
||
|
|
.Substring(2, 5), MethodSig.CreateStatic(_moduleDefMd.ImportAsTypeSig(typeof(double))), MethodAttributes.Private | MethodAttributes.Static | MethodAttributes.HideBySig)
|
||
|
|
{
|
||
|
|
Signature = new MethodSig
|
||
|
|
{
|
||
|
|
Params = { _moduleDefMd.ImportAsTypeSig(typeof(double)) },
|
||
|
|
RetType = _moduleDefMd.ImportAsTypeSig(typeof(double))
|
||
|
|
}
|
||
|
|
};
|
||
|
|
CilBody cilBody = new CilBody();
|
||
|
|
cilBody.Instructions.Add(OpCodes.Ldarg_0.ToInstruction());
|
||
|
|
cilBody.Instructions.Add(OpCodes.Call.ToInstruction(GetMethod(typeof(Math), methodName, new Type[1] { typeof(double) })));
|
||
|
|
cilBody.Instructions.Add(OpCodes.Stloc_0.ToInstruction());
|
||
|
|
cilBody.Instructions.Add(OpCodes.Ldloc_0.ToInstruction());
|
||
|
|
cilBody.Instructions.Add(OpCodes.Ret.ToInstruction());
|
||
|
|
CilBody body = cilBody;
|
||
|
|
methodDefUser.Body = body;
|
||
|
|
methodDefUser.Body.Variables.Add(new Local(_moduleDefMd.ImportAsTypeSig(typeof(double))));
|
||
|
|
return methodDefUser.ResolveMethodDef();
|
||
|
|
}
|
||
|
|
|
||
|
|
private static bool IsSafe(List<Instruction> instructions, int i)
|
||
|
|
{
|
||
|
|
if (new int[5] { -2, -1, 0, 1, 2 }.Contains(instructions[i].GetLdcI4Value()))
|
||
|
|
{
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
return true;
|
||
|
|
}
|
||
|
|
|
||
|
|
private static IMethod GetMethod(Type type, string methodName, Type[] types)
|
||
|
|
{
|
||
|
|
return _moduleDefMd.Import(type.GetMethod(methodName, types));
|
||
|
|
}
|
||
|
|
}
|