864 lines
24 KiB
C#
864 lines
24 KiB
C#
/*
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Copyright (C) 2011-2012 de4dot@gmail.com
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This file is part of de4dot.
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de4dot is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or
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(at your option) any later version.
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de4dot is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with de4dot. If not, see <http://www.gnu.org/licenses/>.
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*/
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using System;
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using System.Collections.Generic;
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using System.Text;
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using dnlib.DotNet;
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using dnlib.DotNet.Emit;
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using de4dot.blocks;
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namespace de4dot.code.deobfuscators.DeepSea {
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class StringDecrypter {
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ModuleDefMD module;
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MethodDefAndDeclaringTypeDict<IDecrypterInfo> methodToInfo = new MethodDefAndDeclaringTypeDict<IDecrypterInfo>();
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DecrypterVersion version = DecrypterVersion.Unknown;
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public enum DecrypterVersion {
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Unknown,
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V1_3,
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V4_0,
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V4_1,
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}
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interface IDecrypterInfo {
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DecrypterVersion Version { get; }
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MethodDef Method { get; }
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string decrypt(object[] args);
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void cleanup();
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}
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static short[] findKey(MethodDef initMethod, FieldDef keyField) {
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var fields = new FieldDefAndDeclaringTypeDict<bool>();
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fields.add(keyField, true);
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return findKey(initMethod, fields);
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}
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static short[] findKey(MethodDef initMethod, FieldDefAndDeclaringTypeDict<bool> fields) {
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var instrs = initMethod.Body.Instructions;
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for (int i = 0; i < instrs.Count - 2; i++) {
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var ldci4 = instrs[i];
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if (!ldci4.IsLdcI4())
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continue;
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var newarr = instrs[i + 1];
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if (newarr.OpCode.Code != Code.Newarr)
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continue;
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if (newarr.Operand.ToString() != "System.Char")
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continue;
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var stloc = instrs[i + 2];
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if (!stloc.IsStloc())
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continue;
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var local = stloc.GetLocal(initMethod.Body.Variables);
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int startInitIndex = i;
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i++;
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var array = ArrayFinder.getInitializedInt16Array(ldci4.GetLdcI4Value(), initMethod, ref i);
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if (array == null)
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continue;
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var field = getStoreField(initMethod, startInitIndex, local);
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if (field == null)
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continue;
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if (fields.find(field))
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return array;
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}
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return null;
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}
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static FieldDef getStoreField(MethodDef method, int startIndex, Local local) {
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var instrs = method.Body.Instructions;
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for (int i = 0; i < instrs.Count - 1; i++) {
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var ldloc = instrs[i];
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if (!ldloc.IsLdloc())
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continue;
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if (ldloc.GetLocal(method.Body.Variables) != local)
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continue;
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var stsfld = instrs[i + 1];
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if (stsfld.OpCode.Code != Code.Stsfld)
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continue;
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return stsfld.Operand as FieldDef;
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}
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return null;
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}
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static bool findMagic(MethodDef method, out int magic) {
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int arg1, arg2;
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return findMagic(method, out arg1, out arg2, out magic);
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}
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static bool findMagic(MethodDef method, out int arg1, out int arg2, out int magic) {
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var instrs = method.Body.Instructions;
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for (int i = 0; i < instrs.Count - 3; i++) {
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if ((arg1 = instrs[i].GetParameterIndex()) < 0)
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continue;
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var ldci4 = instrs[i + 1];
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if (!ldci4.IsLdcI4())
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continue;
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if (instrs[i + 2].OpCode.Code != Code.Xor)
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continue;
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if ((arg2 = instrs[i + 3].GetParameterIndex()) < 0)
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continue;
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magic = ldci4.GetLdcI4Value();
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return true;
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}
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arg1 = arg2 = 0;
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magic = 0;
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return false;
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}
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static void removeInitializeArrayCall(MethodDef method, FieldDef field) {
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var instrs = method.Body.Instructions;
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for (int i = 0; i < instrs.Count - 1; i++) {
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var ldtoken = instrs[i];
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if (ldtoken.OpCode.Code != Code.Ldtoken)
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continue;
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if (ldtoken.Operand != field)
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continue;
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var call = instrs[i + 1];
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if (call.OpCode.Code != Code.Call)
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continue;
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var calledMethod = call.Operand as IMethod;
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if (calledMethod == null)
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continue;
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if (calledMethod.ToString() != "System.Void System.Runtime.CompilerServices.RuntimeHelpers::InitializeArray(System.Array,System.RuntimeFieldHandle)")
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continue;
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instrs[i] = OpCodes.Pop.ToInstruction();
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instrs[i + 1] = OpCodes.Nop.ToInstruction();
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}
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}
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class DecrypterInfo41 : IDecrypterInfo {
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MethodDef cctor;
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int magic;
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int arg1, arg2;
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FieldDefAndDeclaringTypeDict<bool> fields;
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ArrayInfo arrayInfo;
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ushort[] encryptedData;
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short[] key;
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int keyShift;
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DecryptType decryptType;
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// This'll do for now. Code should be added to detect the constants in the code.
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enum DecryptType {
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Type1,
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Type2,
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Type3,
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}
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class ArrayInfo {
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public int sizeInElems;
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public ITypeDefOrRef elementType;
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public FieldDef initField;
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public FieldDef field;
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public ArrayInfo(int sizeInElems, ITypeDefOrRef elementType, FieldDef initField, FieldDef field) {
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this.sizeInElems = sizeInElems;
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this.elementType = elementType;
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this.initField = initField;
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this.field = field;
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}
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}
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public DecrypterVersion Version {
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get { return DecrypterVersion.V4_1; }
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}
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public MethodDef Method { get; private set; }
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public DecrypterInfo41(MethodDef cctor, MethodDef method) {
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this.cctor = cctor;
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Method = method;
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}
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public static bool isPossibleDecrypterMethod(MethodDef method, ref bool? state) {
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if (!checkMethodSignature(method))
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return false;
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var fields = getFields(method);
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if (fields == null || fields.Count != 3)
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return false;
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return true;
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}
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static bool checkMethodSignature(MethodDef method) {
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if (method.MethodSig.GetRetType().GetElementType() != ElementType.String)
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return false;
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int count = 0;
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foreach (var arg in method.MethodSig.GetParams()) {
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if (arg.ElementType == ElementType.I4)
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count++;
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}
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return count >= 2;
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}
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static FieldDefAndDeclaringTypeDict<bool> getFields(MethodDef method) {
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var fields = new FieldDefAndDeclaringTypeDict<bool>();
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foreach (var instr in method.Body.Instructions) {
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if (instr.OpCode.Code != Code.Ldsfld && instr.OpCode.Code != Code.Stsfld)
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continue;
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var field = instr.Operand as FieldDef;
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if (field == null)
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continue;
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if (field.DeclaringType != method.DeclaringType)
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continue;
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fields.add(field, true);
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}
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return fields;
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}
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public bool initialize() {
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if (!findMagic(Method, out arg1, out arg2, out magic))
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return false;
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fields = getFields(Method);
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if (fields == null)
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return false;
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arrayInfo = getArrayInfo(cctor);
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if (arrayInfo == null)
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return false;
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if (arrayInfo.initField.InitialValue.Length % 2 == 1)
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return false;
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encryptedData = new ushort[arrayInfo.initField.InitialValue.Length / 2];
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Buffer.BlockCopy(arrayInfo.initField.InitialValue, 0, encryptedData, 0, arrayInfo.initField.InitialValue.Length);
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decryptType = getDecryptType(Method);
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keyShift = findKeyShift(cctor);
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key = findKey();
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if (key == null || key.Length == 0)
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return false;
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return true;
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}
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static DecryptType getDecryptType(MethodDef method) {
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if (DeobUtils.hasInteger(method, 0xFFF0))
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return DecryptType.Type2;
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if (DeobUtils.hasInteger(method, 0xFFC0))
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return DecryptType.Type3;
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return DecryptType.Type1; // trial
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}
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int findKeyShift(MethodDef method) {
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var instrs = method.Body.Instructions;
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for (int i = 0; i < instrs.Count - 3; i++) {
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int index = i;
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var ldci4 = instrs[index++];
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if (!ldci4.IsLdcI4())
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continue;
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if (ldci4.GetLdcI4Value() != 0xFF)
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continue;
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if (instrs[index++].OpCode.Code != Code.And)
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continue;
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if (instrs[index++].OpCode.Code != Code.Dup)
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continue;
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var ldci4_2 = instrs[index++];
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if (!ldci4_2.IsLdcI4())
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continue;
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if (findNextFieldUse(method, index) < 0)
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continue;
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return ldci4_2.GetLdcI4Value();
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}
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return -1;
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}
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int findNextFieldUse(MethodDef method, int index) {
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var instrs = method.Body.Instructions;
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for (int i = index; i < instrs.Count; i++) {
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var instr = instrs[i];
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if (instr.OpCode.Code != Code.Ldsfld && instr.OpCode.Code != Code.Stsfld)
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continue;
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var field = instr.Operand as IField;
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if (!fields.find(field))
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return -1;
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return i;
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}
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return -1;
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}
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ArrayInfo getArrayInfo(MethodDef method) {
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var instructions = method.Body.Instructions;
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for (int i = 0; i < instructions.Count; i++) {
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var ldci4_arraySizeInBytes = instructions[i];
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if (!ldci4_arraySizeInBytes.IsLdcI4())
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continue;
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i++;
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var instrs = DotNetUtils.getInstructions(instructions, i, OpCodes.Newarr, OpCodes.Dup, OpCodes.Ldtoken, OpCodes.Call, OpCodes.Stsfld);
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if (instrs == null)
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continue;
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int sizeInBytes = ldci4_arraySizeInBytes.GetLdcI4Value();
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var elementType = instrs[0].Operand as ITypeDefOrRef;
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var initField = instrs[2].Operand as FieldDef;
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var field = instrs[4].Operand as FieldDef;
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if (elementType == null)
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continue;
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if (initField == null || initField.InitialValue == null || initField.InitialValue.Length == 0)
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continue;
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if (!fields.find(field))
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continue;
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return new ArrayInfo(sizeInBytes, elementType, initField, field);
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}
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return null;
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}
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short[] findKey() {
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if (cctor.Module.Assembly == null)
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return null;
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var pkt = cctor.Module.Assembly.PublicKeyToken;
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if (!PublicKeyBase.IsNullOrEmpty2(pkt))
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return getPublicKeyTokenKey(pkt.Data);
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return findKey(cctor);
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}
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short[] findKey(MethodDef initMethod) {
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return StringDecrypter.findKey(initMethod, fields);
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}
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short[] getPublicKeyTokenKey(byte[] publicKeyToken) {
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if (keyShift < 0)
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throw new ApplicationException("Could not find shift value");
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var key = new short[publicKeyToken.Length];
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for (int i = 0; i < publicKeyToken.Length; i++) {
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int b = publicKeyToken[i];
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key[i] = (short)((b << keyShift) ^ b);
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}
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return key;
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}
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public string decrypt(object[] args) {
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switch (decryptType) {
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case DecryptType.Type1:
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return decryptTrial((int)args[arg1], (int)args[arg2]);
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case DecryptType.Type2:
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return decryptRetail2((int)args[arg1], (int)args[arg2]);
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case DecryptType.Type3:
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return decryptRetail3((int)args[arg1], (int)args[arg2]);
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default:
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throw new ApplicationException("Unknown type");
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}
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}
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string decryptTrial(int magic2, int magic3) {
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int offset = magic ^ magic2 ^ magic3;
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var keyChar = encryptedData[offset + 1];
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int cachedIndex = encryptedData[offset] ^ keyChar;
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int numChars = ((keyChar ^ encryptedData[offset + 2]) << 16) + (keyChar ^ encryptedData[offset + 3]);
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offset += 4;
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var sb = new StringBuilder(numChars);
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for (int i = 0; i < numChars; i++)
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sb.Append((char)(keyChar ^ encryptedData[offset + i] ^ key[(offset + i) % key.Length]));
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return sb.ToString();
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}
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string decryptRetail2(int magic2, int magic3) {
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return decryptRetail(magic2, magic3, 2, 1, 0, 8, 0);
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}
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string decryptRetail3(int magic2, int magic3) {
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return decryptRetail(magic2, magic3, 0, 2, 1, 0x20, 17);
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}
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string decryptRetail(int magic2, int magic3, int keyCharOffs, int cachedIndexOffs, int flagsOffset, int flag, int keyDispl) {
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int offset = magic ^ magic2 ^ magic3;
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var keyChar = encryptedData[offset + keyCharOffs];
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int cachedIndex = encryptedData[offset + cachedIndexOffs] ^ keyChar;
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int flags = encryptedData[offset + flagsOffset] ^ keyChar;
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int numChars = ((flags >> 1) & ~(flag - 1)) | (flags & (flag - 1));
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if ((flags & flag) != 0) {
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numChars <<= 15;
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numChars |= encryptedData[offset + 3] ^ keyChar;
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offset++;
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}
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offset += 3;
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var sb = new StringBuilder(numChars);
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for (int i = 0; i < numChars; i++)
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sb.Append((char)(keyChar ^ encryptedData[offset + numChars - i - 1] ^ key[(i + 1 + keyDispl + offset) % key.Length]));
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return sb.ToString();
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}
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public void cleanup() {
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arrayInfo.initField.InitialValue = new byte[1];
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arrayInfo.initField.FieldSig.Type = arrayInfo.initField.Module.CorLibTypes.Byte;
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arrayInfo.initField.RVA = 0;
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removeInitializeArrayCall(cctor, arrayInfo.initField);
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}
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}
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class DecrypterInfo40 : IDecrypterInfo {
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MethodDef cctor;
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int magic;
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FieldDef cachedStringsField;
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FieldDef keyField;
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FieldDef encryptedStringsField;
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FieldDef encryptedDataField;
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short[] key;
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ushort[] encryptedData;
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public MethodDef Method { get; private set; }
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public DecrypterVersion Version {
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get { return DecrypterVersion.V4_0; }
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}
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public DecrypterInfo40(MethodDef cctor, MethodDef method) {
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this.cctor = cctor;
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this.Method = method;
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}
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public static bool isPossibleDecrypterMethod(MethodDef method, ref bool? state) {
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if (state == null)
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state = checkFields(method.DeclaringType.Fields);
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if (!state.Value)
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return false;
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return DotNetUtils.isMethod(method, "System.String", "(System.Int32,System.Int32)");
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}
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public bool initialize() {
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if (!findMagic(Method, out magic))
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return false;
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var charArrayFields = findFields();
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if (charArrayFields == null || charArrayFields.Count != 2)
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return false;
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encryptedStringsField = findEncryptedStrings(cctor, charArrayFields, out encryptedDataField);
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if (encryptedStringsField == null)
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return false;
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if (encryptedDataField.InitialValue.Length % 2 == 1)
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return false;
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encryptedData = new ushort[encryptedDataField.InitialValue.Length / 2];
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Buffer.BlockCopy(encryptedDataField.InitialValue, 0, encryptedData, 0, encryptedDataField.InitialValue.Length);
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charArrayFields.Remove(encryptedStringsField);
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keyField = charArrayFields[0];
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key = findKey();
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if (key == null || key.Length == 0)
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return false;
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return true;
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}
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List<FieldDef> findFields() {
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var charArrayFields = new List<FieldDef>();
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foreach (var instr in Method.Body.Instructions) {
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if (instr.OpCode.Code != Code.Stsfld && instr.OpCode.Code != Code.Ldsfld)
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continue;
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var field = instr.Operand as FieldDef;
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if (field == null)
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continue;
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if (!new SigComparer().Equals(Method.DeclaringType, field.DeclaringType))
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continue;
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switch (field.FieldSig.GetFieldType().GetFullName()) {
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case "System.Char[]":
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if (!charArrayFields.Contains(field))
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charArrayFields.Add(field);
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break;
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case "System.String[]":
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if (cachedStringsField != null && cachedStringsField != field)
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return null;
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cachedStringsField = field;
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break;
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default:
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break;
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}
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}
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if (cachedStringsField == null)
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return null;
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return charArrayFields;
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}
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static FieldDef findEncryptedStrings(MethodDef initMethod, List<FieldDef> ourFields, out FieldDef dataField) {
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for (int i = 0; i < initMethod.Body.Instructions.Count; i++) {
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var instrs = DotNetUtils.getInstructions(initMethod.Body.Instructions, i, OpCodes.Ldtoken, OpCodes.Call, OpCodes.Stsfld);
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if (instrs == null)
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continue;
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dataField = instrs[0].Operand as FieldDef;
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if (dataField == null || dataField.InitialValue == null || dataField.InitialValue.Length == 0)
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continue;
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var savedField = instrs[2].Operand as FieldDef;
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if (savedField == null || !matches(ourFields, savedField))
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continue;
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|
|
return savedField;
|
|
}
|
|
|
|
dataField = null;
|
|
return null;
|
|
}
|
|
|
|
static bool matches(IEnumerable<FieldDef> ourFields, FieldDef field) {
|
|
foreach (var ourField in ourFields) {
|
|
if (FieldEqualityComparer.CompareDeclaringTypes.Equals(ourField, field))
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
short[] findKey() {
|
|
if (cctor.Module.Assembly == null)
|
|
return null;
|
|
var pkt = cctor.Module.Assembly.PublicKeyToken;
|
|
if (!PublicKeyBase.IsNullOrEmpty2(pkt))
|
|
return getPublicKeyTokenKey(pkt.Data);
|
|
return findKey(cctor);
|
|
}
|
|
|
|
short[] findKey(MethodDef initMethod) {
|
|
return StringDecrypter.findKey(initMethod, keyField);
|
|
}
|
|
|
|
static short[] getPublicKeyTokenKey(byte[] publicKeyToken) {
|
|
var key = new short[publicKeyToken.Length];
|
|
for (int i = 0; i < publicKeyToken.Length; i++) {
|
|
int b = publicKeyToken[i];
|
|
key[i] = (short)((b << 4) ^ b);
|
|
}
|
|
return key;
|
|
}
|
|
|
|
public string decrypt(object[] args) {
|
|
return decrypt((int)args[0], (int)args[1]);
|
|
}
|
|
|
|
string decrypt(int magic2, int magic3) {
|
|
int index = magic ^ magic2 ^ magic3;
|
|
int cachedIndex = encryptedData[index++];
|
|
int stringLen = encryptedData[index++] + ((int)encryptedData[index++] << 16);
|
|
var sb = new StringBuilder(stringLen);
|
|
for (int i = 0; i < stringLen; i++)
|
|
sb.Append((char)(encryptedData[index++] ^ key[cachedIndex++ % key.Length]));
|
|
return sb.ToString();
|
|
}
|
|
|
|
public void cleanup() {
|
|
encryptedDataField.InitialValue = new byte[1];
|
|
encryptedDataField.FieldSig.Type = encryptedDataField.Module.CorLibTypes.Byte;
|
|
encryptedDataField.RVA = 0;
|
|
removeInitializeArrayCall(cctor, encryptedDataField);
|
|
}
|
|
}
|
|
|
|
class DecrypterInfo13 : IDecrypterInfo {
|
|
MethodDef cctor;
|
|
FieldDef cachedStringsField;
|
|
FieldDef keyField;
|
|
int magic;
|
|
string[] encryptedStrings;
|
|
short[] key;
|
|
|
|
public MethodDef Method { get; private set; }
|
|
|
|
public DecrypterVersion Version {
|
|
get { return DecrypterVersion.V1_3; }
|
|
}
|
|
|
|
public static bool isPossibleDecrypterMethod(MethodDef method, ref bool? state) {
|
|
if (state == null)
|
|
state = checkFields(method.DeclaringType.Fields);
|
|
if (!state.Value)
|
|
return false;
|
|
return DotNetUtils.isMethod(method, "System.String", "(System.Int32)");
|
|
}
|
|
|
|
public DecrypterInfo13(MethodDef cctor, MethodDef method) {
|
|
this.cctor = cctor;
|
|
this.Method = method;
|
|
}
|
|
|
|
public string decrypt(object[] args) {
|
|
return decrypt((int)args[0]);
|
|
}
|
|
|
|
string decrypt(int magic2) {
|
|
var es = encryptedStrings[magic ^ magic2];
|
|
var sb = new StringBuilder(es.Length);
|
|
for (int i = 0; i < es.Length; i++)
|
|
sb.Append((char)(es[i] ^ key[(magic2 + i) % key.Length]));
|
|
return sb.ToString();
|
|
}
|
|
|
|
public bool initialize() {
|
|
if (!findMagic(Method, out magic))
|
|
return false;
|
|
|
|
if (!findFields())
|
|
return false;
|
|
|
|
if (!findEncryptedStrings(Method))
|
|
return false;
|
|
|
|
key = findKey();
|
|
if (key == null || key.Length == 0)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
bool findFields() {
|
|
foreach (var instr in Method.Body.Instructions) {
|
|
if (instr.OpCode.Code != Code.Stsfld && instr.OpCode.Code != Code.Ldsfld)
|
|
continue;
|
|
var field = instr.Operand as FieldDef;
|
|
if (field == null)
|
|
continue;
|
|
if (!new SigComparer().Equals(Method.DeclaringType, field.DeclaringType))
|
|
continue;
|
|
switch (field.FieldSig.GetFieldType().GetFullName()) {
|
|
case "System.Char[]":
|
|
if (keyField != null && keyField != field)
|
|
return false;
|
|
keyField = field;
|
|
break;
|
|
|
|
case "System.String[]":
|
|
if (cachedStringsField != null && cachedStringsField != field)
|
|
return false;
|
|
cachedStringsField = field;
|
|
break;
|
|
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
return keyField != null && cachedStringsField != null;
|
|
}
|
|
|
|
short[] findKey() {
|
|
if (cctor.Module.Assembly == null)
|
|
return null;
|
|
var pkt = cctor.Module.Assembly.PublicKeyToken;
|
|
if (!PublicKeyBase.IsNullOrEmpty2(pkt))
|
|
return getPublicKeyTokenKey(pkt.Data);
|
|
return findKey(cctor);
|
|
}
|
|
|
|
short[] findKey(MethodDef initMethod) {
|
|
return StringDecrypter.findKey(initMethod, keyField);
|
|
}
|
|
|
|
static short[] getPublicKeyTokenKey(byte[] publicKeyToken) {
|
|
var key = new short[publicKeyToken.Length];
|
|
for (int i = 0; i < publicKeyToken.Length; i++) {
|
|
int b = publicKeyToken[i];
|
|
key[i] = (short)((b << 4) ^ b);
|
|
}
|
|
return key;
|
|
}
|
|
|
|
static bool findMagic(MethodDef method, out int magic) {
|
|
var instrs = method.Body.Instructions;
|
|
for (int i = 0; i < instrs.Count - 2; i++) {
|
|
var ldarg = instrs[i];
|
|
if (ldarg.GetParameterIndex() < 0)
|
|
continue;
|
|
var ldci4 = instrs[i + 1];
|
|
if (!ldci4.IsLdcI4())
|
|
continue;
|
|
if (instrs[i + 2].OpCode.Code != Code.Xor)
|
|
continue;
|
|
magic = ldci4.GetLdcI4Value();
|
|
return true;
|
|
}
|
|
magic = 0;
|
|
return false;
|
|
}
|
|
|
|
bool findEncryptedStrings(MethodDef method) {
|
|
var switchInstr = getOnlySwitchInstruction(method);
|
|
if (switchInstr == null)
|
|
return false;
|
|
var targets = (Instruction[])switchInstr.Operand;
|
|
encryptedStrings = new string[targets.Length];
|
|
for (int i = 0; i < targets.Length; i++) {
|
|
var target = targets[i];
|
|
if (target.OpCode.Code != Code.Ldstr)
|
|
return false;
|
|
encryptedStrings[i] = (string)target.Operand;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
static Instruction getOnlySwitchInstruction(MethodDef method) {
|
|
Instruction switchInstr = null;
|
|
foreach (var instr in method.Body.Instructions) {
|
|
if (instr.OpCode.Code != Code.Switch)
|
|
continue;
|
|
if (switchInstr != null)
|
|
return null;
|
|
switchInstr = instr;
|
|
}
|
|
return switchInstr;
|
|
}
|
|
|
|
public void cleanup() {
|
|
}
|
|
|
|
public override string ToString() {
|
|
return string.Format("M:{0:X8} N:{1}", magic, encryptedStrings.Length);
|
|
}
|
|
}
|
|
|
|
public bool Detected {
|
|
get { return methodToInfo.Count != 0; }
|
|
}
|
|
|
|
public DecrypterVersion Version {
|
|
get { return version; }
|
|
}
|
|
|
|
public List<MethodDef> DecrypterMethods {
|
|
get {
|
|
var methods = new List<MethodDef>(methodToInfo.Count);
|
|
foreach (var info in methodToInfo.getValues())
|
|
methods.Add(info.Method);
|
|
return methods;
|
|
}
|
|
}
|
|
|
|
public StringDecrypter(ModuleDefMD module) {
|
|
this.module = module;
|
|
}
|
|
|
|
public void find(ISimpleDeobfuscator simpleDeobfuscator) {
|
|
if (module.Assembly == null)
|
|
return;
|
|
|
|
var pkt = module.Assembly.PublicKeyToken;
|
|
bool hasPublicKeyToken = !PublicKeyBase.IsNullOrEmpty2(pkt);
|
|
foreach (var type in module.GetTypes()) {
|
|
var cctor = type.FindStaticConstructor();
|
|
if (cctor == null)
|
|
continue;
|
|
|
|
bool deobfuscatedCctor = false;
|
|
bool? v13State = null, v40State = null, v41State = null;
|
|
foreach (var method in type.Methods) {
|
|
if (!method.IsStatic || method.Body == null)
|
|
continue;
|
|
|
|
IDecrypterInfo info = null;
|
|
|
|
if (DecrypterInfo13.isPossibleDecrypterMethod(method, ref v13State)) {
|
|
deobfuscateCctor(simpleDeobfuscator, cctor, ref deobfuscatedCctor, hasPublicKeyToken);
|
|
simpleDeobfuscator.deobfuscate(method);
|
|
info = getInfoV13(cctor, method);
|
|
}
|
|
else if (DecrypterInfo40.isPossibleDecrypterMethod(method, ref v40State)) {
|
|
deobfuscateCctor(simpleDeobfuscator, cctor, ref deobfuscatedCctor, hasPublicKeyToken);
|
|
simpleDeobfuscator.deobfuscate(method);
|
|
info = getInfoV40(cctor, method);
|
|
}
|
|
else if (DecrypterInfo41.isPossibleDecrypterMethod(method, ref v41State)) {
|
|
deobfuscateCctor(simpleDeobfuscator, cctor, ref deobfuscatedCctor, hasPublicKeyToken);
|
|
simpleDeobfuscator.deobfuscate(method);
|
|
info = getInfoV41(cctor, method);
|
|
}
|
|
|
|
if (info == null)
|
|
continue;
|
|
methodToInfo.add(method, info);
|
|
version = info.Version;
|
|
}
|
|
}
|
|
}
|
|
|
|
static void deobfuscateCctor(ISimpleDeobfuscator simpleDeobfuscator, MethodDef cctor, ref bool deobfuscatedCctor, bool hasPublicKeyToken) {
|
|
if (deobfuscatedCctor || hasPublicKeyToken)
|
|
return;
|
|
simpleDeobfuscator.deobfuscate(cctor);
|
|
deobfuscatedCctor = true;
|
|
}
|
|
|
|
static bool checkFields(IEnumerable<FieldDef> fields) {
|
|
bool foundCharAry = false, foundStringAry = false;
|
|
foreach (var field in fields) {
|
|
if (foundCharAry && foundStringAry)
|
|
break;
|
|
switch (field.FieldSig.GetFieldType().GetFullName()) {
|
|
case "System.Char[]":
|
|
foundCharAry = true;
|
|
break;
|
|
case "System.String[]":
|
|
foundStringAry = true;
|
|
break;
|
|
}
|
|
}
|
|
return foundCharAry && foundStringAry;
|
|
}
|
|
|
|
DecrypterInfo13 getInfoV13(MethodDef cctor, MethodDef method) {
|
|
var info = new DecrypterInfo13(cctor, method);
|
|
if (!info.initialize())
|
|
return null;
|
|
return info;
|
|
}
|
|
|
|
DecrypterInfo40 getInfoV40(MethodDef cctor, MethodDef method) {
|
|
var info = new DecrypterInfo40(cctor, method);
|
|
if (!info.initialize())
|
|
return null;
|
|
return info;
|
|
}
|
|
|
|
DecrypterInfo41 getInfoV41(MethodDef cctor, MethodDef method) {
|
|
var info = new DecrypterInfo41(cctor, method);
|
|
if (!info.initialize())
|
|
return null;
|
|
return info;
|
|
}
|
|
|
|
public string decrypt(IMethod method, object[] args) {
|
|
var info = methodToInfo.find(method);
|
|
return info.decrypt(args);
|
|
}
|
|
|
|
public void cleanup() {
|
|
foreach (var info in methodToInfo.getValues())
|
|
info.cleanup();
|
|
}
|
|
}
|
|
}
|