803 lines
27 KiB
C#
803 lines
27 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.IO;
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using System.Text;
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using Mono.Cecil;
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using Mono.Cecil.Cil;
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using Mono.Cecil.Metadata;
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using Mono.MyStuff;
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using de4dot.blocks;
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using de4dot.PE;
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namespace de4dot.code.deobfuscators.Confuser {
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class JitMethodsDecrypter : MethodsDecrypterBase, IStringDecrypter {
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MethodDefinition compileMethod;
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MethodDefinition hookConstructStr;
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MethodDataIndexes methodDataIndexes;
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ConfuserVersion version = ConfuserVersion.Unknown;
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enum ConfuserVersion {
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Unknown,
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v17_r73404,
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v17_r73430,
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v17_r73477,
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v17_r73479,
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v17_r74021,
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v18_r75257,
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v18_r75288,
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v18_r75291,
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v18_r75402,
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v19_r75725,
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}
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struct MethodDataIndexes {
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public int codeSize;
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public int maxStack;
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public int ehs;
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public int localVarSigTok;
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public int options;
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}
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public JitMethodsDecrypter(ModuleDefinition module, ISimpleDeobfuscator simpleDeobfuscator)
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: base(module, simpleDeobfuscator) {
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}
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public JitMethodsDecrypter(ModuleDefinition module, ISimpleDeobfuscator simpleDeobfuscator, JitMethodsDecrypter other)
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: base(module, simpleDeobfuscator, other) {
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if (other != null)
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this.version = other.version;
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}
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protected override bool checkType(TypeDefinition type, MethodDefinition initMethod) {
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if (type == null)
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return false;
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compileMethod = findCompileMethod(type);
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if (compileMethod == null)
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return false;
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decryptMethod = findDecryptMethod(type);
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if (decryptMethod == null)
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return false;
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var theVersion = ConfuserVersion.Unknown;
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switch (type.NestedTypes.Count) {
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case 35:
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if (type.Fields.Count == 9)
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theVersion = ConfuserVersion.v17_r73404;
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else if (type.Fields.Count == 10)
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theVersion = ConfuserVersion.v17_r73430;
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else
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return false;
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break;
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case 38:
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switch (countInt32s(compileMethod, 0xFF)) {
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case 2: theVersion = ConfuserVersion.v17_r73477; break;
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case 4: theVersion = ConfuserVersion.v17_r73479; break;
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default: return false;
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}
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break;
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case 39:
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if (!DotNetUtils.callsMethod(initMethod, "System.Void System.Console::WriteLine(System.Char)")) {
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if (DotNetUtils.callsMethod(decryptMethod, "System.Security.Cryptography.Rijndael System.Security.Cryptography.Rijndael::Create()"))
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theVersion = ConfuserVersion.v17_r74021;
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else
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theVersion = ConfuserVersion.v18_r75291;
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}
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else if (DotNetUtils.callsMethod(decryptMethod, "System.Security.Cryptography.Rijndael System.Security.Cryptography.Rijndael::Create()"))
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theVersion = ConfuserVersion.v18_r75257;
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else
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theVersion = ConfuserVersion.v18_r75288;
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break;
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case 27:
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if (DotNetUtils.callsMethod(initMethod, "System.Int32 System.String::get_Length()"))
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theVersion = ConfuserVersion.v18_r75402;
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else
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theVersion = ConfuserVersion.v19_r75725;
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break;
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default:
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return false;
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}
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if (theVersion >= ConfuserVersion.v17_r73477) {
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hookConstructStr = findHookConstructStr(type);
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if (hookConstructStr == null)
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return false;
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}
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version = theVersion;
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return true;
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}
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static int countInt32s(MethodDefinition method, int val) {
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int count = 0;
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foreach (var instr in method.Body.Instructions) {
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if (!DotNetUtils.isLdcI4(instr))
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continue;
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if (DotNetUtils.getLdcI4Value(instr) == val)
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count++;
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}
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return count;
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}
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static MethodDefinition findCompileMethod(TypeDefinition type) {
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foreach (var method in type.Methods) {
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if (!method.IsStatic || method.Body == null)
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continue;
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if (method.Parameters.Count != 6)
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continue;
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if (method.MethodReturnType.ReturnType.EType != ElementType.U4)
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continue;
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if (method.Parameters[0].ParameterType.EType != ElementType.I)
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continue;
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if (method.Parameters[3].ParameterType.EType != ElementType.U4)
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continue;
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if (method.Parameters[4].ParameterType.FullName != "System.Byte**")
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continue;
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if (method.Parameters[5].ParameterType.FullName != "System.UInt32*")
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continue;
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return method;
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}
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return null;
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}
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static MethodDefinition findHookConstructStr(TypeDefinition type) {
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foreach (var nested in type.NestedTypes) {
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if (nested.Fields.Count != 8 && nested.Fields.Count != 10)
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continue;
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foreach (var method in nested.Methods) {
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if (method.IsStatic || method.Body == null)
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continue;
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if (method.Parameters.Count != 4)
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continue;
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if (method.Parameters[0].ParameterType.EType != ElementType.I)
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continue;
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if (method.Parameters[1].ParameterType.EType != ElementType.I)
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continue;
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if (method.Parameters[2].ParameterType.EType != ElementType.U4)
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continue;
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if (method.Parameters[3].ParameterType.EType != ElementType.I && method.Parameters[3].ParameterType.FullName != "System.IntPtr&")
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continue;
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return method;
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}
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}
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return null;
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}
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public void initialize() {
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if (initMethod == null)
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return;
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if (!initializeKeys())
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throw new ApplicationException("Could not find all decryption keys");
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if (!initializeMethodDataIndexes(compileMethod))
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throw new ApplicationException("Could not find MethodData indexes");
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}
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bool initializeKeys() {
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switch (version) {
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case ConfuserVersion.v17_r73404: return initializeKeys_v17_r73404();
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case ConfuserVersion.v17_r73430: return initializeKeys_v17_r73404();
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case ConfuserVersion.v17_r73477: return initializeKeys_v17_r73404();
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case ConfuserVersion.v17_r73479: return initializeKeys_v17_r73404();
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case ConfuserVersion.v17_r74021: return initializeKeys_v17_r73404();
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case ConfuserVersion.v18_r75257: return initializeKeys_v17_r73404();
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case ConfuserVersion.v18_r75288: return initializeKeys_v17_r73404();
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case ConfuserVersion.v18_r75291: return initializeKeys_v17_r73404();
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case ConfuserVersion.v18_r75402: return initializeKeys_v18_r75402();
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case ConfuserVersion.v19_r75725: return initializeKeys_v18_r75402();
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default: throw new ApplicationException("Invalid version");
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}
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}
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bool initializeKeys_v17_r73404() {
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simpleDeobfuscator.deobfuscate(initMethod);
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if (!findLKey0(initMethod, out lkey0))
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return false;
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if (!findKey0_v16_r71742(initMethod, out key0))
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return false;
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if (!findKey1(initMethod, out key1))
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return false;
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if (!findKey2Key3(initMethod, out key2, out key3))
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return false;
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simpleDeobfuscator.deobfuscate(decryptMethod);
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if (!findKey6(decryptMethod, out key6))
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return false;
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return true;
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}
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bool initializeKeys_v18_r75402() {
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simpleDeobfuscator.deobfuscate(initMethod);
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if (!findLKey0(initMethod, out lkey0))
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return false;
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if (!findKey0_v16_r71742(initMethod, out key0))
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return false;
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if (!findKey1(initMethod, out key1))
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return false;
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if (!findKey2Key3(initMethod, out key2, out key3))
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return false;
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simpleDeobfuscator.deobfuscate(compileMethod);
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if (!findKey4(compileMethod, out key4))
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return false;
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simpleDeobfuscator.deobfuscate(hookConstructStr);
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if (!findKey5(hookConstructStr, out key5))
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return false;
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simpleDeobfuscator.deobfuscate(decryptMethod);
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if (!findKey6(decryptMethod, out key6))
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return false;
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return true;
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}
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static bool findKey4(MethodDefinition method, out uint key) {
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var instrs = method.Body.Instructions;
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for (int index = 0; index < instrs.Count; index++) {
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index = ConfuserUtils.findCallMethod(instrs, index, Code.Call, "System.Void System.Runtime.InteropServices.Marshal::Copy(System.Byte[],System.Int32,System.IntPtr,System.Int32)");
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if (index < 0)
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break;
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if (index + 2 >= instrs.Count)
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continue;
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if (!DotNetUtils.isLdloc(instrs[index + 1]))
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continue;
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var ldci4 = instrs[index + 2];
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if (!DotNetUtils.isLdcI4(ldci4))
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continue;
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key = (uint)DotNetUtils.getLdcI4Value(ldci4);
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return true;
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}
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key = 0;
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return false;
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}
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static bool findKey5(MethodDefinition method, out uint key) {
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var instrs = method.Body.Instructions;
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for (int i = 0; i + 4 < instrs.Count; i++) {
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int index = i;
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var ldci4_8 = instrs[index++];
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if (!DotNetUtils.isLdcI4(ldci4_8) || DotNetUtils.getLdcI4Value(ldci4_8) != 8)
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continue;
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if (instrs[index++].OpCode.Code != Code.Shl)
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continue;
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if (instrs[index++].OpCode.Code != Code.Or)
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continue;
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var ldci4 = instrs[index++];
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if (!DotNetUtils.isLdcI4(ldci4))
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continue;
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if (instrs[index++].OpCode.Code != Code.Xor)
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continue;
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key = (uint)DotNetUtils.getLdcI4Value(ldci4);
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return true;
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}
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key = 0;
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return false;
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}
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bool initializeMethodDataIndexes(MethodDefinition compileMethod) {
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switch (version) {
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case ConfuserVersion.v17_r73404: return true;
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case ConfuserVersion.v17_r73430: return true;
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case ConfuserVersion.v17_r73477: return initializeMethodDataIndexes_v17_r73477(compileMethod);
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case ConfuserVersion.v17_r73479: return initializeMethodDataIndexes_v17_r73477(compileMethod);
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case ConfuserVersion.v17_r74021: return initializeMethodDataIndexes_v17_r73477(compileMethod);
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case ConfuserVersion.v18_r75257: return initializeMethodDataIndexes_v17_r73477(compileMethod);
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case ConfuserVersion.v18_r75288: return initializeMethodDataIndexes_v17_r73477(compileMethod);
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case ConfuserVersion.v18_r75291: return initializeMethodDataIndexes_v17_r73477(compileMethod);
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case ConfuserVersion.v18_r75402: return initializeMethodDataIndexes_v17_r73477(compileMethod);
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case ConfuserVersion.v19_r75725: return initializeMethodDataIndexes_v17_r73477(compileMethod);
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default: throw new ApplicationException("Invalid version");
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}
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}
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bool initializeMethodDataIndexes_v17_r73477(MethodDefinition method) {
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simpleDeobfuscator.deobfuscate(method);
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var methodDataType = findFirstThreeIndexes(method, out methodDataIndexes.maxStack, out methodDataIndexes.ehs, out methodDataIndexes.options);
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if (methodDataType == null)
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return false;
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if (!findLocalVarSigTokIndex(method, methodDataType, out methodDataIndexes.localVarSigTok))
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return false;
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if (!findCodeSizeIndex(method, methodDataType, out methodDataIndexes.codeSize))
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return false;
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return true;
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}
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static TypeDefinition findFirstThreeIndexes(MethodDefinition method, out int maxStackIndex, out int ehsIndex, out int optionsIndex) {
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var instrs = method.Body.Instructions;
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for (int i = 0; i < instrs.Count; i++) {
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int index1 = findLdfldStind(instrs, i, false, true);
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if (index1 < 0)
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break;
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i = index1;
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int index2 = findLdfldStind(instrs, index1 + 1, true, true);
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if (index2 < 0)
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continue;
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int index3 = findLdfldStind(instrs, index2 + 1, true, false);
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if (index3 < 0)
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continue;
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var field1 = instrs[index1].Operand as FieldDefinition;
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var field2 = instrs[index2].Operand as FieldDefinition;
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var field3 = instrs[index3].Operand as FieldDefinition;
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if (field1 == null || field2 == null || field3 == null)
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continue;
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if (field1.DeclaringType != field2.DeclaringType || field1.DeclaringType != field3.DeclaringType)
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continue;
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maxStackIndex = getInstanceFieldIndex(field1);
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ehsIndex = getInstanceFieldIndex(field2);
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optionsIndex = getInstanceFieldIndex(field3);
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return field1.DeclaringType;
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}
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maxStackIndex = -1;
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ehsIndex = -1;
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optionsIndex = -1;
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return null;
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}
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static bool findLocalVarSigTokIndex(MethodDefinition method, TypeDefinition methodDataType, out int localVarSigTokIndex) {
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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 ldfld = instrs[i];
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if (ldfld.OpCode.Code != Code.Ldfld)
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continue;
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var field = ldfld.Operand as FieldDefinition;
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if (field == null || field.DeclaringType != methodDataType)
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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 MethodDefinition;
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if (calledMethod == null || !calledMethod.IsStatic || calledMethod.DeclaringType != method.DeclaringType)
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continue;
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localVarSigTokIndex = getInstanceFieldIndex(field);
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return true;
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}
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localVarSigTokIndex = -1;
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return false;
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}
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static bool findCodeSizeIndex(MethodDefinition method, TypeDefinition methodDataType, out int codeSizeIndex) {
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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 ldfld = instrs[i];
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if (ldfld.OpCode.Code != Code.Ldfld)
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continue;
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var field = ldfld.Operand as FieldDefinition;
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if (field == null || field.DeclaringType != methodDataType)
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continue;
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if (instrs[i+1].OpCode.Code != Code.Stfld)
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continue;
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codeSizeIndex = getInstanceFieldIndex(field);
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return true;
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}
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codeSizeIndex = -1;
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return false;
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}
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static int getInstanceFieldIndex(FieldDefinition field) {
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int i = 0;
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foreach (var f in field.DeclaringType.Fields) {
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if (f.IsStatic)
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continue;
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if (f == field)
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return i;
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i++;
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}
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throw new ApplicationException("Could not find field");
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}
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static int findLdfldStind(IList<Instruction> instrs, int index, bool onlyInBlock, bool checkStindi4) {
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for (int i = index; i < instrs.Count - 1; i++) {
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var ldfld = instrs[i];
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if (onlyInBlock && ldfld.OpCode.FlowControl != FlowControl.Next)
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break;
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if (ldfld.OpCode.Code != Code.Ldfld)
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continue;
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var stindi4 = instrs[i + 1];
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if (checkStindi4 && stindi4.OpCode.Code != Code.Stind_I4)
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continue;
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return i;
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}
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return -1;
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}
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public bool decrypt(PeImage peImage, byte[] fileData, ref DumpedMethods dumpedMethods) {
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if (initMethod == null)
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return false;
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switch (version) {
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case ConfuserVersion.v17_r73404: return decrypt_v17_r73404(peImage, fileData, ref dumpedMethods);
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case ConfuserVersion.v17_r73430: return decrypt_v17_r73404(peImage, fileData, ref dumpedMethods);
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case ConfuserVersion.v17_r73477: return decrypt_v17_r73477(peImage, fileData, ref dumpedMethods);
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case ConfuserVersion.v17_r73479: return decrypt_v17_r73479(peImage, fileData, ref dumpedMethods);
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case ConfuserVersion.v17_r74021: return decrypt_v17_r73479(peImage, fileData, ref dumpedMethods);
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case ConfuserVersion.v18_r75257: return decrypt_v17_r73479(peImage, fileData, ref dumpedMethods);
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case ConfuserVersion.v18_r75288: return decrypt_v17_r73479(peImage, fileData, ref dumpedMethods);
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case ConfuserVersion.v18_r75291: return decrypt_v17_r73479(peImage, fileData, ref dumpedMethods);
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case ConfuserVersion.v18_r75402: return decrypt_v18_r75402(peImage, fileData, ref dumpedMethods);
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case ConfuserVersion.v19_r75725: return decrypt_v18_r75402(peImage, fileData, ref dumpedMethods);
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default: throw new ApplicationException("Unknown version");
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}
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}
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bool decrypt_v17_r73404(PeImage peImage, byte[] fileData, ref DumpedMethods dumpedMethods) {
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methodsData = decryptMethodsData_v17_r73404(peImage);
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dumpedMethods = decrypt_v17_r73404(peImage, fileData);
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return dumpedMethods != null;
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}
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DumpedMethods decrypt_v17_r73404(PeImage peImage, byte[] fileData) {
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var dumpedMethods = new DumpedMethods();
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var metadataTables = peImage.Cor20Header.createMetadataTables();
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var methodDef = metadataTables.getMetadataType(MetadataIndex.iMethodDef);
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uint methodDefOffset = methodDef.fileOffset;
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for (int i = 0; i < methodDef.rows; i++, methodDefOffset += methodDef.totalSize) {
|
|
uint bodyRva = peImage.offsetReadUInt32(methodDefOffset);
|
|
if (bodyRva == 0)
|
|
continue;
|
|
uint bodyOffset = peImage.rvaToOffset(bodyRva);
|
|
|
|
if (!isEncryptedMethod(fileData, (int)bodyOffset))
|
|
continue;
|
|
|
|
var dm = new DumpedMethod();
|
|
dm.token = (uint)(0x06000001 + i);
|
|
dm.mdImplFlags = peImage.offsetReadUInt16(methodDefOffset + (uint)methodDef.fields[1].offset);
|
|
dm.mdFlags = peImage.offsetReadUInt16(methodDefOffset + (uint)methodDef.fields[2].offset);
|
|
dm.mdName = peImage.offsetRead(methodDefOffset + (uint)methodDef.fields[3].offset, methodDef.fields[3].size);
|
|
dm.mdSignature = peImage.offsetRead(methodDefOffset + (uint)methodDef.fields[4].offset, methodDef.fields[4].size);
|
|
dm.mdParamList = peImage.offsetRead(methodDefOffset + (uint)methodDef.fields[5].offset, methodDef.fields[5].size);
|
|
|
|
int key = BitConverter.ToInt32(fileData, (int)bodyOffset + 6);
|
|
int mdOffs = BitConverter.ToInt32(fileData, (int)bodyOffset + 2) ^ key;
|
|
int len = BitConverter.ToInt32(fileData, (int)bodyOffset + 11) ^ ~key;
|
|
var codeData = decryptMethodData_v17_r73404(methodsData, mdOffs + 2, (uint)key, len);
|
|
|
|
byte[] code, extraSections;
|
|
var reader = new BinaryReader(new MemoryStream(codeData));
|
|
var mbHeader = MethodBodyParser.parseMethodBody(reader, out code, out extraSections);
|
|
if (reader.BaseStream.Position != reader.BaseStream.Length)
|
|
throw new ApplicationException("Invalid method data");
|
|
|
|
dm.mhFlags = mbHeader.flags;
|
|
dm.mhMaxStack = mbHeader.maxStack;
|
|
dm.code = code;
|
|
dm.extraSections = extraSections;
|
|
dm.mhCodeSize = (uint)dm.code.Length;
|
|
dm.mhLocalVarSigTok = mbHeader.localVarSigTok;
|
|
|
|
dumpedMethods.add(dm);
|
|
}
|
|
|
|
return dumpedMethods;
|
|
}
|
|
|
|
bool decrypt_v17_r73477(PeImage peImage, byte[] fileData, ref DumpedMethods dumpedMethods) {
|
|
methodsData = decryptMethodsData_v17_r73404(peImage);
|
|
dumpedMethods = decrypt_v17_r73477(peImage, fileData);
|
|
return dumpedMethods != null;
|
|
}
|
|
|
|
DumpedMethods decrypt_v17_r73477(PeImage peImage, byte[] fileData) {
|
|
return decrypt(peImage, fileData, new DecryptMethodData_v17_r73477());
|
|
}
|
|
|
|
bool decrypt_v17_r73479(PeImage peImage, byte[] fileData, ref DumpedMethods dumpedMethods) {
|
|
methodsData = decryptMethodsData_v17_r73404(peImage);
|
|
dumpedMethods = decrypt_v17_r73479(peImage, fileData);
|
|
return dumpedMethods != null;
|
|
}
|
|
|
|
DumpedMethods decrypt_v17_r73479(PeImage peImage, byte[] fileData) {
|
|
return decrypt(peImage, fileData, new DecryptMethodData_v17_r73479());
|
|
}
|
|
|
|
bool decrypt_v18_r75402(PeImage peImage, byte[] fileData, ref DumpedMethods dumpedMethods) {
|
|
if (peImage.OptionalHeader.checkSum == 0)
|
|
return false;
|
|
methodsData = decryptMethodsData_v17_r73404(peImage);
|
|
dumpedMethods = decrypt_v18_r75402(peImage, fileData);
|
|
return dumpedMethods != null;
|
|
}
|
|
|
|
DumpedMethods decrypt_v18_r75402(PeImage peImage, byte[] fileData) {
|
|
return decrypt(peImage, fileData, new DecryptMethodData_v18_r75402(this));
|
|
}
|
|
|
|
abstract class DecryptMethodData {
|
|
public abstract void decrypt(byte[] fileData, int offset, uint k1, int size, out uint[] methodData, out byte[] codeData);
|
|
|
|
public bool isCodeFollowedByExtraSections(uint options) {
|
|
return (options >> 8) == 0;
|
|
}
|
|
}
|
|
|
|
class DecryptMethodData_v17_r73477 : DecryptMethodData {
|
|
public override void decrypt(byte[] fileData, int offset, uint k1, int size, out uint[] methodData, out byte[] codeData) {
|
|
var data = new byte[size];
|
|
Array.Copy(fileData, offset, data, 0, data.Length);
|
|
var key = BitConverter.GetBytes(k1);
|
|
for (int i = 0; i < data.Length; i++)
|
|
data[i] ^= key[i & 3];
|
|
|
|
methodData = new uint[5];
|
|
Buffer.BlockCopy(data, 0, methodData, 0, 20);
|
|
codeData = new byte[size - 20];
|
|
Array.Copy(data, 20, codeData, 0, codeData.Length);
|
|
}
|
|
}
|
|
|
|
class DecryptMethodData_v17_r73479 : DecryptMethodData {
|
|
public override void decrypt(byte[] fileData, int offset, uint k1, int size, out uint[] methodData, out byte[] codeData) {
|
|
var data = new byte[size];
|
|
Array.Copy(fileData, offset, data, 0, data.Length);
|
|
uint k = k1;
|
|
for (int i = 0; i < data.Length; i++) {
|
|
data[i] ^= (byte)k;
|
|
k = (k * data[i] + k1) % 0xFF;
|
|
}
|
|
|
|
methodData = new uint[5];
|
|
Buffer.BlockCopy(data, 0, methodData, 0, 20);
|
|
codeData = new byte[size - 20];
|
|
Array.Copy(data, 20, codeData, 0, codeData.Length);
|
|
}
|
|
}
|
|
|
|
class DecryptMethodData_v18_r75402 : DecryptMethodData {
|
|
JitMethodsDecrypter jitDecrypter;
|
|
|
|
public DecryptMethodData_v18_r75402(JitMethodsDecrypter jitDecrypter) {
|
|
this.jitDecrypter = jitDecrypter;
|
|
}
|
|
|
|
public override void decrypt(byte[] fileData, int offset, uint k1, int size, out uint[] methodData, out byte[] codeData) {
|
|
var data = new byte[size];
|
|
Array.Copy(fileData, offset, data, 0, data.Length);
|
|
uint k2 = jitDecrypter.key4 * k1;
|
|
for (int i = 0; i < data.Length; i++) {
|
|
data[i] ^= (byte)k2;
|
|
k2 = (byte)((k2 * data[i] + k1) % 0xFF);
|
|
}
|
|
|
|
methodData = new uint[5];
|
|
Buffer.BlockCopy(data, 0, methodData, 0, 20);
|
|
codeData = new byte[size - 20];
|
|
Array.Copy(data, 20, codeData, 0, codeData.Length);
|
|
}
|
|
}
|
|
|
|
DumpedMethods decrypt(PeImage peImage, byte[] fileData, DecryptMethodData decrypter) {
|
|
var dumpedMethods = new DumpedMethods { StringDecrypter = this };
|
|
|
|
var metadataTables = peImage.Cor20Header.createMetadataTables();
|
|
var methodDef = metadataTables.getMetadataType(MetadataIndex.iMethodDef);
|
|
uint methodDefOffset = methodDef.fileOffset;
|
|
for (int i = 0; i < methodDef.rows; i++, methodDefOffset += methodDef.totalSize) {
|
|
uint bodyRva = peImage.offsetReadUInt32(methodDefOffset);
|
|
if (bodyRva == 0)
|
|
continue;
|
|
uint bodyOffset = peImage.rvaToOffset(bodyRva);
|
|
|
|
if (!isEncryptedMethod(fileData, (int)bodyOffset))
|
|
continue;
|
|
|
|
var dm = new DumpedMethod();
|
|
dm.token = (uint)(0x06000001 + i);
|
|
dm.mdImplFlags = peImage.offsetReadUInt16(methodDefOffset + (uint)methodDef.fields[1].offset);
|
|
dm.mdFlags = peImage.offsetReadUInt16(methodDefOffset + (uint)methodDef.fields[2].offset);
|
|
dm.mdName = peImage.offsetRead(methodDefOffset + (uint)methodDef.fields[3].offset, methodDef.fields[3].size);
|
|
dm.mdSignature = peImage.offsetRead(methodDefOffset + (uint)methodDef.fields[4].offset, methodDef.fields[4].size);
|
|
dm.mdParamList = peImage.offsetRead(methodDefOffset + (uint)methodDef.fields[5].offset, methodDef.fields[5].size);
|
|
|
|
int key = BitConverter.ToInt32(fileData, (int)bodyOffset + 6);
|
|
int mdOffs = BitConverter.ToInt32(fileData, (int)bodyOffset + 2) ^ key;
|
|
int len = BitConverter.ToInt32(fileData, (int)bodyOffset + 11) ^ ~key;
|
|
int methodDataOffset = mdOffs + 2;
|
|
uint[] methodData;
|
|
byte[] codeData;
|
|
decrypter.decrypt(methodsData, methodDataOffset, (uint)key, len, out methodData, out codeData);
|
|
|
|
dm.mhFlags = 0x03;
|
|
int maxStack = (int)methodData[methodDataIndexes.maxStack];
|
|
dm.mhMaxStack = (ushort)maxStack;
|
|
dm.mhLocalVarSigTok = methodData[methodDataIndexes.localVarSigTok];
|
|
if (dm.mhLocalVarSigTok != 0 && (dm.mhLocalVarSigTok >> 24) != 0x11)
|
|
throw new ApplicationException("Invalid local var sig token");
|
|
int numExceptions = (int)methodData[methodDataIndexes.ehs];
|
|
uint options = methodData[methodDataIndexes.options];
|
|
int codeSize = (int)methodData[methodDataIndexes.codeSize];
|
|
|
|
var codeDataReader = new BinaryReader(new MemoryStream(codeData));
|
|
if (decrypter.isCodeFollowedByExtraSections(options)) {
|
|
dm.code = codeDataReader.ReadBytes(codeSize);
|
|
dm.extraSections = readExceptionHandlers(codeDataReader, numExceptions);
|
|
}
|
|
else {
|
|
dm.extraSections = readExceptionHandlers(codeDataReader, numExceptions);
|
|
dm.code = codeDataReader.ReadBytes(codeSize);
|
|
}
|
|
if (codeDataReader.BaseStream.Position != codeDataReader.BaseStream.Length)
|
|
throw new ApplicationException("Invalid method data");
|
|
if (dm.extraSections != null)
|
|
dm.mhFlags |= 8;
|
|
dm.mhCodeSize = (uint)dm.code.Length;
|
|
|
|
// Figure out if the original method was tiny or not.
|
|
bool isTiny = dm.code.Length <= 0x3F &&
|
|
dm.mhLocalVarSigTok == 0 &&
|
|
dm.extraSections == null &&
|
|
dm.mhMaxStack == 8;
|
|
if (isTiny)
|
|
dm.mhFlags |= 0x10; // Set 'init locals'
|
|
dm.mhFlags |= (ushort)(options & 0x10); // copy 'init locals' bit
|
|
|
|
dumpedMethods.add(dm);
|
|
}
|
|
|
|
return dumpedMethods;
|
|
}
|
|
|
|
static bool isEncryptedMethod(byte[] fileData, int offset) {
|
|
return fileData[offset] == 0x46 &&
|
|
fileData[offset + 1] == 0x21 &&
|
|
fileData[offset + 10] == 0x20 &&
|
|
fileData[offset + 15] == 0x26;
|
|
}
|
|
|
|
static byte[] readExceptionHandlers(BinaryReader reader, int numExceptions) {
|
|
if (numExceptions == 0)
|
|
return null;
|
|
|
|
var memStream = new MemoryStream();
|
|
var writer = new BinaryWriter(memStream);
|
|
|
|
ulong header64 = (((ulong)numExceptions * 24) << 8) | 0x41;
|
|
if (header64 > uint.MaxValue)
|
|
throw new ApplicationException("Too many exception handlers...");
|
|
writer.Write((uint)header64);
|
|
for (int i = 0; i < numExceptions; i++) {
|
|
writer.Write(reader.ReadUInt32()); // flags
|
|
writer.Write(reader.ReadUInt32()); // try offset
|
|
writer.Write(reader.ReadUInt32()); // try length
|
|
writer.Write(reader.ReadUInt32()); // handler offset
|
|
writer.Write(reader.ReadUInt32()); // handler length
|
|
writer.Write(reader.ReadUInt32()); // catch token or filter offset
|
|
}
|
|
|
|
return memStream.ToArray();
|
|
}
|
|
|
|
byte[] decryptMethodData_v17_r73404(byte[] fileData, int offset, uint k1, int size) {
|
|
var data = new byte[size];
|
|
var kbytes = BitConverter.GetBytes(k1);
|
|
for (int i = 0; i < size; i++)
|
|
data[i] = (byte)(fileData[offset + i] ^ kbytes[i & 3]);
|
|
return data;
|
|
}
|
|
|
|
string IStringDecrypter.decrypt(uint token) {
|
|
if ((token & 0xFF800000) != 0x70800000)
|
|
return null;
|
|
var reader = new BinaryReader(new MemoryStream(methodsData));
|
|
reader.BaseStream.Position = (token & ~0xFF800000) + 2;
|
|
int len = reader.ReadInt32();
|
|
if ((len & 1) != 1)
|
|
throw new ApplicationException("Invalid string len");
|
|
int chars = len / 2;
|
|
var sb = new StringBuilder(chars);
|
|
for (int i = 0; i < chars; i++)
|
|
sb.Append((char)(reader.ReadUInt16() ^ key5));
|
|
return sb.ToString();
|
|
}
|
|
|
|
public override bool getRevisionRange(out int minRev, out int maxRev) {
|
|
switch (version) {
|
|
case ConfuserVersion.Unknown:
|
|
minRev = maxRev = 0;
|
|
return false;
|
|
|
|
case ConfuserVersion.v17_r73404:
|
|
minRev = 73404;
|
|
maxRev = 73404;
|
|
return true;
|
|
|
|
case ConfuserVersion.v17_r73430:
|
|
minRev = 73430;
|
|
maxRev = 73430;
|
|
return true;
|
|
|
|
case ConfuserVersion.v17_r73477:
|
|
minRev = 73477;
|
|
maxRev = 73477;
|
|
return true;
|
|
|
|
case ConfuserVersion.v17_r73479:
|
|
minRev = 73479;
|
|
maxRev = 73822;
|
|
return true;
|
|
|
|
case ConfuserVersion.v17_r74021:
|
|
minRev = 74021;
|
|
maxRev = 75184;
|
|
return true;
|
|
|
|
case ConfuserVersion.v18_r75257:
|
|
minRev = 75257;
|
|
maxRev = 75267;
|
|
return true;
|
|
|
|
case ConfuserVersion.v18_r75288:
|
|
minRev = 75288;
|
|
maxRev = 75288;
|
|
return true;
|
|
|
|
case ConfuserVersion.v18_r75291:
|
|
minRev = 75291;
|
|
maxRev = 75369;
|
|
return true;
|
|
|
|
case ConfuserVersion.v18_r75402:
|
|
minRev = 75402;
|
|
maxRev = 75720;
|
|
return true;
|
|
|
|
case ConfuserVersion.v19_r75725:
|
|
minRev = 75725;
|
|
maxRev = int.MaxValue;
|
|
return true;
|
|
|
|
default: throw new ApplicationException("Invalid version");
|
|
}
|
|
}
|
|
}
|
|
}
|