/*
Copyright (C) 2011 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.IO;
using System.Security.Cryptography;
using Mono.Cecil;
namespace de4dot.code.deobfuscators {
static class DeobUtils {
public static void decryptAndAddResources(ModuleDefinition module, string encryptedName, Func decryptResource) {
Log.v("Decrypting resources, name: {0}", Utils.toCsharpString(encryptedName));
var decryptedResourceData = decryptResource();
if (decryptedResourceData == null)
throw new ApplicationException("decryptedResourceData is null");
var resourceModule = ModuleDefinition.ReadModule(new MemoryStream(decryptedResourceData));
Log.indent();
foreach (var rsrc in resourceModule.Resources) {
Log.v("Adding decrypted resource {0}", Utils.toCsharpString(rsrc.Name));
module.Resources.Add(rsrc);
}
Log.deIndent();
}
public static T lookup(ModuleDefinition module, T def, string errorMessage) where T : MemberReference {
if (def == null)
return null;
var newDef = module.LookupToken(def.MetadataToken.ToInt32()) as T;
if (newDef == null)
throw new ApplicationException(errorMessage);
return newDef;
}
public static byte[] readModule(ModuleDefinition module) {
return Utils.readFile(module.FullyQualifiedName);
}
public static bool isCode(short[] nativeCode, byte[] code) {
if (nativeCode.Length != code.Length)
return false;
for (int i = 0; i < nativeCode.Length; i++) {
if (nativeCode[i] == -1)
continue;
if ((byte)nativeCode[i] != code[i])
return false;
}
return true;
}
public static byte[] aesDecrypt(byte[] data, byte[] key, byte[] iv) {
using (var aes = new RijndaelManaged { Mode = CipherMode.CBC }) {
using (var transform = aes.CreateDecryptor(key, iv)) {
return transform.TransformFinalBlock(data, 0, data.Length);
}
}
}
public static string getExtension(ModuleKind kind) {
switch (kind) {
case ModuleKind.Dll:
return ".dll";
case ModuleKind.NetModule:
return ".netmodule";
case ModuleKind.Console:
case ModuleKind.Windows:
default:
return ".exe";
}
}
}
}