86 lines
2.7 KiB
C#
86 lines
2.7 KiB
C#
/*
|
|
Copyright (C) 2011-2013 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 <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
using System;
|
|
using System.Text;
|
|
using dnlib.DotNet;
|
|
|
|
namespace de4dot.code.deobfuscators.Agile_NET {
|
|
class StringDecrypter {
|
|
ModuleDefMD module;
|
|
TypeDef stringDecrypterType;
|
|
MethodDef stringDecrypterMethod;
|
|
byte[] stringDecrypterKey;
|
|
|
|
public bool Detected {
|
|
get { return stringDecrypterMethod != null; }
|
|
}
|
|
|
|
public TypeDef Type {
|
|
get { return stringDecrypterType; }
|
|
}
|
|
|
|
public MethodDef Method {
|
|
get { return stringDecrypterMethod; }
|
|
set { stringDecrypterMethod = value; }
|
|
}
|
|
|
|
public StringDecrypter(ModuleDefMD module, MethodDef stringDecrypterMethod) {
|
|
this.module = module;
|
|
this.stringDecrypterMethod = stringDecrypterMethod;
|
|
}
|
|
|
|
public StringDecrypter(ModuleDefMD module, StringDecrypter oldOne) {
|
|
this.module = module;
|
|
stringDecrypterType = Lookup(oldOne.stringDecrypterType, "Could not find stringDecrypterType");
|
|
stringDecrypterMethod = Lookup(oldOne.stringDecrypterMethod, "Could not find stringDecrypterMethod");
|
|
stringDecrypterKey = oldOne.stringDecrypterKey;
|
|
}
|
|
|
|
T Lookup<T>(T def, string errorMessage) where T : class, ICodedToken {
|
|
return DeobUtils.Lookup(module, def, errorMessage);
|
|
}
|
|
|
|
public void Find() {
|
|
stringDecrypterKey = new byte[1] { 0xFF };
|
|
foreach (var type in module.Types) {
|
|
if (type.FullName == "<D234>" || type.FullName == "<ClassD234>") {
|
|
stringDecrypterType = type;
|
|
foreach (var field in type.Fields) {
|
|
if (field.FullName == "<D234> <D234>::345" || field.FullName == "<ClassD234>/D234 <ClassD234>::345") {
|
|
stringDecrypterKey = field.InitialValue;
|
|
break;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
public string Decrypt(string es) {
|
|
if (stringDecrypterKey == null)
|
|
throw new ApplicationException("Trying to decrypt strings when stringDecrypterKey is null (could not find it!)");
|
|
char[] buf = new char[es.Length];
|
|
for (int i = 0; i < es.Length; i++)
|
|
buf[i] = (char)(es[i] ^ stringDecrypterKey[i % stringDecrypterKey.Length]);
|
|
return new string(buf);
|
|
}
|
|
}
|
|
}
|