From 9db99626f2b3ff84c6f5e0158aa10aeb4fac7d62 Mon Sep 17 00:00:00 2001 From: de4dot Date: Sun, 5 Aug 2012 20:25:43 +0200 Subject: [PATCH] Refactor --- de4dot.code/de4dot.code.csproj | 2 + .../Confuser/ConstantsDecrypter.cs | 52 +-- .../Confuser/ConstantsDecrypterBase.cs | 331 ++++++++++++++ .../Confuser/ConstantsDecrypterUtils.cs | 97 +++++ .../Confuser/ConstantsDecrypterV15.cs | 406 +++--------------- .../deobfuscators/Confuser/Deobfuscator.cs | 30 +- 6 files changed, 499 insertions(+), 419 deletions(-) create mode 100644 de4dot.code/deobfuscators/Confuser/ConstantsDecrypterBase.cs create mode 100644 de4dot.code/deobfuscators/Confuser/ConstantsDecrypterUtils.cs diff --git a/de4dot.code/de4dot.code.csproj b/de4dot.code/de4dot.code.csproj index 8494d77e..a1c6b5df 100644 --- a/de4dot.code/de4dot.code.csproj +++ b/de4dot.code/de4dot.code.csproj @@ -72,6 +72,8 @@ + + diff --git a/de4dot.code/deobfuscators/Confuser/ConstantsDecrypter.cs b/de4dot.code/deobfuscators/Confuser/ConstantsDecrypter.cs index 4c9dfd52..1d7b4713 100644 --- a/de4dot.code/deobfuscators/Confuser/ConstantsDecrypter.cs +++ b/de4dot.code/deobfuscators/Confuser/ConstantsDecrypter.cs @@ -155,62 +155,14 @@ namespace de4dot.code.deobfuscators.Confuser { return; simpleDeobfuscator.deobfuscate(cctor, true); - if ((dictField = findDictField(cctor, cctor.DeclaringType)) == null) + if ((dictField = ConstantsDecrypterUtils.findDictField(cctor, cctor.DeclaringType)) == null) return; - if ((dataField = findDataField(cctor, cctor.DeclaringType)) == null) + if ((dataField = ConstantsDecrypterUtils.findDataField(cctor, cctor.DeclaringType)) == null) return; installMethod = cctor; } - static FieldDefinition findDictField(MethodDefinition method, TypeDefinition declaringType) { - var instrs = method.Body.Instructions; - for (int i = 0; i < instrs.Count - 1; i++) { - var newobj = instrs[i]; - if (newobj.OpCode.Code != Code.Newobj) - continue; - var ctor = newobj.Operand as MethodReference; - if (ctor == null || ctor.FullName != "System.Void System.Collections.Generic.Dictionary`2::.ctor()") - continue; - - var stsfld = instrs[i + 1]; - if (stsfld.OpCode.Code != Code.Stsfld) - continue; - var field = stsfld.Operand as FieldDefinition; - if (field == null || field.DeclaringType != declaringType) - continue; - if (field.FieldType.FullName != "System.Collections.Generic.Dictionary`2") - continue; - - return field; - } - return null; - } - - static FieldDefinition findDataField(MethodDefinition method, TypeDefinition declaringType) { - var instrs = method.Body.Instructions; - for (int i = 0; i < instrs.Count - 1; i++) { - var callvirt = instrs[i]; - if (callvirt.OpCode.Code != Code.Callvirt) - continue; - var calledMethod = callvirt.Operand as MethodReference; - if (calledMethod == null || calledMethod.FullName != "System.Byte[] System.IO.MemoryStream::ToArray()") - continue; - - var stsfld = instrs[i + 1]; - if (stsfld.OpCode.Code != Code.Stsfld) - continue; - var field = stsfld.Operand as FieldDefinition; - if (field == null || field.DeclaringType != declaringType) - continue; - if (field.FieldType.FullName != "System.Byte[]") - continue; - - return field; - } - return null; - } - public void initialize() { if (installMethod == null) return; diff --git a/de4dot.code/deobfuscators/Confuser/ConstantsDecrypterBase.cs b/de4dot.code/deobfuscators/Confuser/ConstantsDecrypterBase.cs new file mode 100644 index 00000000..1a351f2f --- /dev/null +++ b/de4dot.code/deobfuscators/Confuser/ConstantsDecrypterBase.cs @@ -0,0 +1,331 @@ +/* + Copyright (C) 2011-2012 de4dot@gmail.com + + This file is part of de4dot. + + de4dot is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + de4dot is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with de4dot. If not, see . +*/ + +using System; +using System.Collections.Generic; +using System.IO; +using System.Text; +using Mono.Cecil; +using Mono.Cecil.Cil; +using de4dot.blocks; + +namespace de4dot.code.deobfuscators.Confuser { + abstract class ConstantsDecrypterBase { + protected ModuleDefinition module; + protected byte[] fileData; + protected ISimpleDeobfuscator simpleDeobfuscator; + MethodDefinitionAndDeclaringTypeDict methodToDecrypterInfo = new MethodDefinitionAndDeclaringTypeDict(); + FieldDefinitionAndDeclaringTypeDict fields = new FieldDefinitionAndDeclaringTypeDict(); + protected EmbeddedResource resource; + protected BinaryReader reader; + + public class DecrypterInfo { + public MethodDefinition decryptMethod; + public MethodDefinition nativeMethod; + public uint key0, key1, key2, key3; + public byte doubleType, singleType, int32Type, int64Type, stringType; + + public void initialize() { + if (!initializeKeys()) + throw new ApplicationException("Could not find all keys"); + if (!initializeTypeCodes()) + throw new ApplicationException("Could not find all type codes"); + } + + bool initializeKeys() { + if (!findKey0(decryptMethod, out key0)) + return false; + if (!findKey1(decryptMethod, out key1)) + return false; + if (!findKey2Key3(decryptMethod, out key2, out key3)) + return false; + + return true; + } + + static bool findKey0(MethodDefinition method, out uint key) { + var instrs = method.Body.Instructions; + for (int i = 0; i < instrs.Count - 5; i++) { + if (!DotNetUtils.isLdloc(instrs[i])) + continue; + if (instrs[i + 1].OpCode.Code != Code.Or) + continue; + var ldci4 = instrs[i + 2]; + if (!DotNetUtils.isLdcI4(ldci4)) + continue; + if (instrs[i + 3].OpCode.Code != Code.Xor) + continue; + if (instrs[i + 4].OpCode.Code != Code.Add) + continue; + if (!DotNetUtils.isStloc(instrs[i + 5])) + continue; + + key = (uint)DotNetUtils.getLdcI4Value(ldci4); + return true; + } + key = 0; + return false; + } + + static bool findKey1(MethodDefinition method, out uint key) { + var instrs = method.Body.Instructions; + for (int i = 0; i < instrs.Count; i++) { + int index = ConfuserUtils.findCallMethod(instrs, i, Code.Callvirt, "System.Int32 System.Reflection.MemberInfo::get_MetadataToken()"); + if (index < 0) + break; + if (index + 2 > instrs.Count) + break; + if (!DotNetUtils.isStloc(instrs[index + 1])) + continue; + var ldci4 = instrs[index + 2]; + if (!DotNetUtils.isLdcI4(ldci4)) + continue; + + key = (uint)DotNetUtils.getLdcI4Value(ldci4); + return true; + } + key = 0; + return false; + } + + static bool findKey2Key3(MethodDefinition method, out uint key2, out uint key3) { + var instrs = method.Body.Instructions; + for (int i = 0; i < instrs.Count - 3; i++) { + var ldci4_1 = instrs[i]; + if (!DotNetUtils.isLdcI4(ldci4_1)) + continue; + if (!DotNetUtils.isStloc(instrs[i + 1])) + continue; + var ldci4_2 = instrs[i + 2]; + if (!DotNetUtils.isLdcI4(ldci4_2)) + continue; + if (!DotNetUtils.isStloc(instrs[i + 3])) + continue; + + key2 = (uint)DotNetUtils.getLdcI4Value(ldci4_1); + key3 = (uint)DotNetUtils.getLdcI4Value(ldci4_2); + return true; + } + key2 = 0; + key3 = 0; + return false; + } + + bool initializeTypeCodes() { + var allBlocks = new Blocks(decryptMethod).MethodBlocks.getAllBlocks(); + if (!findTypeCode(allBlocks, out doubleType, Code.Call, "System.Double System.BitConverter::ToDouble(System.Byte[],System.Int32)")) + return false; + if (!findTypeCode(allBlocks, out singleType, Code.Call, "System.Single System.BitConverter::ToSingle(System.Byte[],System.Int32)")) + return false; + if (!findTypeCode(allBlocks, out int32Type, Code.Call, "System.Int32 System.BitConverter::ToInt32(System.Byte[],System.Int32)")) + return false; + if (!findTypeCode(allBlocks, out int64Type, Code.Call, "System.Int64 System.BitConverter::ToInt64(System.Byte[],System.Int32)")) + return false; + if (!findTypeCode(allBlocks, out stringType, Code.Callvirt, "System.String System.Text.Encoding::GetString(System.Byte[])") && + !findTypeCode(allBlocks, out stringType, Code.Callvirt, "System.String System.Text.Encoding::GetString(System.Byte[],System.Int32,System.Int32)")) + return false; + return true; + } + + static bool findTypeCode(IList allBlocks, out byte typeCode, Code callCode, string bitConverterMethod) { + foreach (var block in allBlocks) { + if (block.Sources.Count != 1) + continue; + int index = ConfuserUtils.findCallMethod(block.Instructions, 0, callCode, bitConverterMethod); + if (index < 0) + continue; + + if (!findTypeCode(block.Sources[0], out typeCode)) + continue; + + return true; + } + typeCode = 0; + return false; + } + + static Block fixBlock(Block block) { + if (block.Sources.Count != 1) + return block; + if (block.getOnlyTarget() == null) + return block; + if (block.Instructions.Count == 0) { + } + else if (block.Instructions.Count == 1 && block.Instructions[0].OpCode.Code == Code.Nop) { + } + else + return block; + return block.Sources[0]; + } + + static bool findTypeCode(Block block, out byte typeCode) { + block = fixBlock(block); + + var instrs = block.Instructions; + int numCeq = 0; + for (int i = instrs.Count - 1; i >= 0; i--) { + var instr = instrs[i]; + if (instr.OpCode.Code == Code.Ceq) { + numCeq++; + continue; + } + if (!DotNetUtils.isLdcI4(instr.Instruction)) + continue; + if (numCeq != 0 && numCeq != 2) + continue; + + typeCode = (byte)DotNetUtils.getLdcI4Value(instr.Instruction); + return true; + } + typeCode = 0; + return false; + } + + public uint calcHash(uint x) { + uint h0 = key1 ^ x; + uint h1 = key2; + uint h2 = key3; + for (uint i = 1; i <= 64; i++) { + h0 = (h0 << 8) | (h0 >> 24); + uint n = h0 & 0x3F; + if (n >= 0 && n < 16) { + h1 |= ((byte)(h0 >> 8) & (h0 >> 16)) ^ (byte)~h0; + h2 ^= (h0 * i + 1) & 0xF; + h0 += (h1 | h2) ^ key0; + } + else if (n >= 16 && n < 32) { + h1 ^= ((h0 & 0x00FF00FF) << 8) ^ (ushort)((h0 >> 8) | ~h0); + h2 += (h0 * i) & 0x1F; + h0 |= (h1 + ~h2) & key0; + } + else if (n >= 32 && n < 48) { + h1 += (byte)(h0 | (h0 >> 16)) + (~h0 & 0xFF); + h2 -= ~(h0 + n) % 48; + h0 ^= (h1 % h2) | key0; + } + else if (n >= 48 && n < 64) { + h1 ^= ((byte)(h0 >> 16) | ~(h0 & 0xFF)) * (~h0 & 0x00FF0000); + h2 += (h0 ^ (i - 1)) % n; + h0 -= ~(h1 ^ h2) + key0; + } + } + return h0; + } + } + + public abstract bool Detected { get; } + + public EmbeddedResource Resource { + get { return resource; } + } + + public IEnumerable Fields { + get { return fields.getKeys(); } + } + + protected bool HasDecrypterInfos { + get { return methodToDecrypterInfo.Count > 0; } + } + + public IEnumerable DecrypterInfos { + get { return methodToDecrypterInfo.getValues(); } + } + + public ConstantsDecrypterBase(ModuleDefinition module, byte[] fileData, ISimpleDeobfuscator simpleDeobfuscator) { + this.module = module; + this.fileData = fileData; + this.simpleDeobfuscator = simpleDeobfuscator; + } + + public abstract void initialize(); + + protected void add(DecrypterInfo info) { + methodToDecrypterInfo.add(info.decryptMethod, info); + } + + protected bool add(FieldDefinition field) { + if (field == null) + return false; + fields.add(field, true); + return true; + } + + protected void initializeDecrypterInfos() { + foreach (var info in methodToDecrypterInfo.getValues()) { + simpleDeobfuscator.deobfuscate(info.decryptMethod); + info.initialize(); + } + } + + public object decryptInt32(MethodDefinition caller, MethodDefinition decryptMethod, object[] args) { + var info = methodToDecrypterInfo.find(decryptMethod); + byte typeCode; + var data = decryptData(info, caller, args, out typeCode); + if (typeCode != info.int32Type) + return null; + if (data.Length != 4) + throw new ApplicationException("Invalid data length"); + return BitConverter.ToInt32(data, 0); + } + + public object decryptInt64(MethodDefinition caller, MethodDefinition decryptMethod, object[] args) { + var info = methodToDecrypterInfo.find(decryptMethod); + byte typeCode; + var data = decryptData(info, caller, args, out typeCode); + if (typeCode != info.int64Type) + return null; + if (data.Length != 8) + throw new ApplicationException("Invalid data length"); + return BitConverter.ToInt64(data, 0); + } + + public object decryptSingle(MethodDefinition caller, MethodDefinition decryptMethod, object[] args) { + var info = methodToDecrypterInfo.find(decryptMethod); + byte typeCode; + var data = decryptData(info, caller, args, out typeCode); + if (typeCode != info.singleType) + return null; + if (data.Length != 4) + throw new ApplicationException("Invalid data length"); + return BitConverter.ToSingle(data, 0); + } + + public object decryptDouble(MethodDefinition caller, MethodDefinition decryptMethod, object[] args) { + var info = methodToDecrypterInfo.find(decryptMethod); + byte typeCode; + var data = decryptData(info, caller, args, out typeCode); + if (typeCode != info.doubleType) + return null; + if (data.Length != 8) + throw new ApplicationException("Invalid data length"); + return BitConverter.ToDouble(data, 0); + } + + public string decryptString(MethodDefinition caller, MethodDefinition decryptMethod, object[] args) { + var info = methodToDecrypterInfo.find(decryptMethod); + byte typeCode; + var data = decryptData(info, caller, args, out typeCode); + if (typeCode != info.stringType) + return null; + return Encoding.UTF8.GetString(data); + } + + protected abstract byte[] decryptData(DecrypterInfo info, MethodDefinition caller, object[] args, out byte typeCode); + } +} diff --git a/de4dot.code/deobfuscators/Confuser/ConstantsDecrypterUtils.cs b/de4dot.code/deobfuscators/Confuser/ConstantsDecrypterUtils.cs new file mode 100644 index 00000000..77269fa9 --- /dev/null +++ b/de4dot.code/deobfuscators/Confuser/ConstantsDecrypterUtils.cs @@ -0,0 +1,97 @@ +/* + Copyright (C) 2011-2012 de4dot@gmail.com + + This file is part of de4dot. + + de4dot is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation, either version 3 of the License, or + (at your option) any later version. + + de4dot is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with de4dot. If not, see . +*/ + +using Mono.Cecil; +using Mono.Cecil.Cil; + +namespace de4dot.code.deobfuscators.Confuser { + static class ConstantsDecrypterUtils { + public static FieldDefinition findDictField(MethodDefinition method, TypeDefinition declaringType) { + var instrs = method.Body.Instructions; + for (int i = 0; i < instrs.Count - 1; i++) { + var newobj = instrs[i]; + if (newobj.OpCode.Code != Code.Newobj) + continue; + var ctor = newobj.Operand as MethodReference; + if (ctor == null || ctor.FullName != "System.Void System.Collections.Generic.Dictionary`2::.ctor()") + continue; + + var stsfld = instrs[i + 1]; + if (stsfld.OpCode.Code != Code.Stsfld) + continue; + var field = stsfld.Operand as FieldDefinition; + if (field == null || field.DeclaringType != declaringType) + continue; + if (field.FieldType.FullName != "System.Collections.Generic.Dictionary`2") + continue; + + return field; + } + return null; + } + + public static FieldDefinition findDataField(MethodDefinition method, TypeDefinition declaringType) { + var instrs = method.Body.Instructions; + for (int i = 0; i < instrs.Count - 1; i++) { + var callvirt = instrs[i]; + if (callvirt.OpCode.Code != Code.Callvirt) + continue; + var calledMethod = callvirt.Operand as MethodReference; + if (calledMethod == null || calledMethod.FullName != "System.Byte[] System.IO.MemoryStream::ToArray()") + continue; + + var stsfld = instrs[i + 1]; + if (stsfld.OpCode.Code != Code.Stsfld) + continue; + var field = stsfld.Operand as FieldDefinition; + if (field == null || field.DeclaringType != declaringType) + continue; + if (field.FieldType.FullName != "System.Byte[]") + continue; + + return field; + } + return null; + } + + public static FieldDefinition findStreamField(MethodDefinition method, TypeDefinition declaringType) { + var instrs = method.Body.Instructions; + for (int i = 0; i < instrs.Count - 1; i++) { + var newobj = instrs[i]; + if (newobj.OpCode.Code != Code.Newobj) + continue; + var ctor = newobj.Operand as MethodReference; + if (ctor == null || ctor.FullName != "System.Void System.IO.MemoryStream::.ctor()") + continue; + + var stsfld = instrs[i + 1]; + if (stsfld.OpCode.Code != Code.Stsfld) + continue; + var field = stsfld.Operand as FieldDefinition; + if (field == null || field.DeclaringType != declaringType) + continue; + if (field.FieldType.FullName != "System.IO.MemoryStream") + continue; + + return field; + } + return null; + } + } +} diff --git a/de4dot.code/deobfuscators/Confuser/ConstantsDecrypterV15.cs b/de4dot.code/deobfuscators/Confuser/ConstantsDecrypterV15.cs index 69324ece..d13b4301 100644 --- a/de4dot.code/deobfuscators/Confuser/ConstantsDecrypterV15.cs +++ b/de4dot.code/deobfuscators/Confuser/ConstantsDecrypterV15.cs @@ -20,25 +20,15 @@ using System; using System.Collections.Generic; using System.IO; -using System.Text; using Mono.Cecil; using Mono.Cecil.Cil; using de4dot.blocks; using de4dot.PE; namespace de4dot.code.deobfuscators.Confuser { - class ConstantsDecrypterV15 { - ModuleDefinition module; - byte[] fileData; - ISimpleDeobfuscator simpleDeobfuscator; - FieldDefinition dictField, streamField; - MethodDefinition decryptMethod; - MethodDefinition nativeMethod; - EmbeddedResource resource; - uint key0, key1, key2, key3; - byte doubleType, singleType, int32Type, int64Type, stringType; - BinaryReader reader; + class ConstantsDecrypterV15 : ConstantsDecrypterBase { ConfuserVersion version = ConfuserVersion.Unknown; + DecrypterInfo theDecrypterInfo; enum ConfuserVersion { Unknown, @@ -53,35 +43,12 @@ namespace de4dot.code.deobfuscators.Confuser { v17_r73822_native, } - public MethodDefinition Method { - get { return decryptMethod; } + public override bool Detected { + get { return theDecrypterInfo != null; } } - public MethodDefinition NativeMethod { - get { return nativeMethod; } - } - - public IEnumerable Fields { - get { - return new List { - streamField, - dictField, - }; - } - } - - public EmbeddedResource Resource { - get { return resource; } - } - - public bool Detected { - get { return decryptMethod != null; } - } - - public ConstantsDecrypterV15(ModuleDefinition module, byte[] fileData, ISimpleDeobfuscator simpleDeobfuscator) { - this.module = module; - this.fileData = fileData; - this.simpleDeobfuscator = simpleDeobfuscator; + public ConstantsDecrypterV15(ModuleDefinition module, byte[] fileData, ISimpleDeobfuscator simpleDeobfuscator) + : base(module, fileData, simpleDeobfuscator) { } static readonly string[] requiredLocals1 = new string[] { @@ -108,6 +75,7 @@ namespace de4dot.code.deobfuscators.Confuser { if (!DotNetUtils.isMethod(method, "System.Object", "(System.UInt32)")) continue; + DecrypterInfo info = new DecrypterInfo(); var localTypes = new LocalTypes(method); if (localTypes.all(requiredLocals1)) { if (localTypes.exists("System.Collections.BitArray")) // or System.Random @@ -123,7 +91,7 @@ namespace de4dot.code.deobfuscators.Confuser { version = ConfuserVersion.v17_r73740_dynamic; } else if (DotNetUtils.callsMethod(method, "System.String System.Text.Encoding::GetString(System.Byte[],System.Int32,System.Int32)")) { - if ((nativeMethod = findNativeMethod(method)) == null) + if ((info.nativeMethod = findNativeMethod(method)) == null) version = ConfuserVersion.v17_r73764_dynamic; else version = ConfuserVersion.v17_r73764_native; @@ -136,7 +104,7 @@ namespace de4dot.code.deobfuscators.Confuser { DeobUtils.hasInteger(method, 0x10000) && DeobUtils.hasInteger(method, 0xFFFF)) version = ConfuserVersion.v17_r73822_normal; - else if ((nativeMethod = findNativeMethod(method)) == null) + else if ((info.nativeMethod = findNativeMethod(method)) == null) version = ConfuserVersion.v17_r73822_dynamic; else version = ConfuserVersion.v17_r73822_native; @@ -144,7 +112,9 @@ namespace de4dot.code.deobfuscators.Confuser { else continue; - decryptMethod = method; + info.decryptMethod = method; + theDecrypterInfo = info; + add(info); break; } } @@ -166,30 +136,26 @@ namespace de4dot.code.deobfuscators.Confuser { return null; } - public void initialize() { - if ((resource = findResource(decryptMethod)) == null) + public override void initialize() { + if ((resource = findResource(theDecrypterInfo.decryptMethod)) == null) throw new ApplicationException("Could not find encrypted consts resource"); - simpleDeobfuscator.deobfuscate(decryptMethod); - if (!initializeKeys()) - throw new ApplicationException("Could not find all keys"); - if (!initializeTypeCodes()) - throw new ApplicationException("Could not find all type codes"); - if (!initializeFields()) + initializeDecrypterInfos(); + if (!initializeFields(theDecrypterInfo)) throw new ApplicationException("Could not find all fields"); var constants = DeobUtils.inflate(resource.GetResourceData(), true); reader = new BinaryReader(new MemoryStream(constants)); } - bool initializeFields() { + bool initializeFields(DecrypterInfo info) { switch (version) { case ConfuserVersion.v17_r73822_normal: case ConfuserVersion.v17_r73822_dynamic: case ConfuserVersion.v17_r73822_native: - if ((dictField = findDictField(decryptMethod, decryptMethod.DeclaringType)) == null) + if (!add(ConstantsDecrypterUtils.findDictField(info.decryptMethod, info.decryptMethod.DeclaringType))) return false; - if ((streamField = findStreamField(decryptMethod, decryptMethod.DeclaringType)) == null) + if (!add(ConstantsDecrypterUtils.findStreamField(info.decryptMethod, info.decryptMethod.DeclaringType))) return false; break; @@ -200,285 +166,40 @@ namespace de4dot.code.deobfuscators.Confuser { return true; } - static FieldDefinition findDictField(MethodDefinition method, TypeDefinition declaringType) { - var instrs = method.Body.Instructions; - for (int i = 0; i < instrs.Count - 1; i++) { - var newobj = instrs[i]; - if (newobj.OpCode.Code != Code.Newobj) - continue; - var ctor = newobj.Operand as MethodReference; - if (ctor == null || ctor.FullName != "System.Void System.Collections.Generic.Dictionary`2::.ctor()") - continue; - - var stsfld = instrs[i + 1]; - if (stsfld.OpCode.Code != Code.Stsfld) - continue; - var field = stsfld.Operand as FieldDefinition; - if (field == null || field.DeclaringType != declaringType) - continue; - if (field.FieldType.FullName != "System.Collections.Generic.Dictionary`2") - continue; - - return field; - } - return null; - } - - static FieldDefinition findStreamField(MethodDefinition method, TypeDefinition declaringType) { - var instrs = method.Body.Instructions; - for (int i = 0; i < instrs.Count - 1; i++) { - var newobj = instrs[i]; - if (newobj.OpCode.Code != Code.Newobj) - continue; - var ctor = newobj.Operand as MethodReference; - if (ctor == null || ctor.FullName != "System.Void System.IO.MemoryStream::.ctor()") - continue; - - var stsfld = instrs[i + 1]; - if (stsfld.OpCode.Code != Code.Stsfld) - continue; - var field = stsfld.Operand as FieldDefinition; - if (field == null || field.DeclaringType != declaringType) - continue; - if (field.FieldType.FullName != "System.IO.MemoryStream") - continue; - - return field; - } - return null; - } - - bool initializeKeys() { - if (!findKey0(decryptMethod, out key0)) - return false; - if (!findKey1(decryptMethod, out key1)) - return false; - if (!findKey2Key3(decryptMethod, out key2, out key3)) - return false; - - return true; - } - - static bool findKey0(MethodDefinition method, out uint key) { - var instrs = method.Body.Instructions; - for (int i = 0; i < instrs.Count - 5; i++) { - if (!DotNetUtils.isLdloc(instrs[i])) - continue; - if (instrs[i + 1].OpCode.Code != Code.Or) - continue; - var ldci4 = instrs[i + 2]; - if (!DotNetUtils.isLdcI4(ldci4)) - continue; - if (instrs[i + 3].OpCode.Code != Code.Xor) - continue; - if (instrs[i + 4].OpCode.Code != Code.Add) - continue; - if (!DotNetUtils.isStloc(instrs[i + 5])) - continue; - - key = (uint)DotNetUtils.getLdcI4Value(ldci4); - return true; - } - key = 0; - return false; - } - - static bool findKey1(MethodDefinition method, out uint key) { - var instrs = method.Body.Instructions; - for (int i = 0; i < instrs.Count; i++) { - int index = ConfuserUtils.findCallMethod(instrs, i, Code.Callvirt, "System.Int32 System.Reflection.MemberInfo::get_MetadataToken()"); - if (index < 0) - break; - if (index + 2 > instrs.Count) - break; - if (!DotNetUtils.isStloc(instrs[index + 1])) - continue; - var ldci4 = instrs[index + 2]; - if (!DotNetUtils.isLdcI4(ldci4)) - continue; - - key = (uint)DotNetUtils.getLdcI4Value(ldci4); - return true; - } - key = 0; - return false; - } - - static bool findKey2Key3(MethodDefinition method, out uint key2, out uint key3) { - var instrs = method.Body.Instructions; - for (int i = 0; i < instrs.Count - 3; i++) { - var ldci4_1 = instrs[i]; - if (!DotNetUtils.isLdcI4(ldci4_1)) - continue; - if (!DotNetUtils.isStloc(instrs[i + 1])) - continue; - var ldci4_2 = instrs[i + 2]; - if (!DotNetUtils.isLdcI4(ldci4_2)) - continue; - if (!DotNetUtils.isStloc(instrs[i + 3])) - continue; - - key2 = (uint)DotNetUtils.getLdcI4Value(ldci4_1); - key3 = (uint)DotNetUtils.getLdcI4Value(ldci4_2); - return true; - } - key2 = 0; - key3 = 0; - return false; - } - - bool initializeTypeCodes() { - var allBlocks = new Blocks(decryptMethod).MethodBlocks.getAllBlocks(); - if (!findTypeCode(allBlocks, out doubleType, Code.Call, "System.Double System.BitConverter::ToDouble(System.Byte[],System.Int32)")) - return false; - if (!findTypeCode(allBlocks, out singleType, Code.Call, "System.Single System.BitConverter::ToSingle(System.Byte[],System.Int32)")) - return false; - if (!findTypeCode(allBlocks, out int32Type, Code.Call, "System.Int32 System.BitConverter::ToInt32(System.Byte[],System.Int32)")) - return false; - if (!findTypeCode(allBlocks, out int64Type, Code.Call, "System.Int64 System.BitConverter::ToInt64(System.Byte[],System.Int32)")) - return false; - if (!findTypeCode(allBlocks, out stringType, Code.Callvirt, "System.String System.Text.Encoding::GetString(System.Byte[])") && - !findTypeCode(allBlocks, out stringType, Code.Callvirt, "System.String System.Text.Encoding::GetString(System.Byte[],System.Int32,System.Int32)")) - return false; - return true; - } - - static bool findTypeCode(IList allBlocks, out byte typeCode, Code callCode, string bitConverterMethod) { - foreach (var block in allBlocks) { - if (block.Sources.Count != 1) - continue; - int index = ConfuserUtils.findCallMethod(block.Instructions, 0, callCode, bitConverterMethod); - if (index < 0) - continue; - - if (!findTypeCode(block.Sources[0], out typeCode)) - continue; - - return true; - } - typeCode = 0; - return false; - } - - static Block fixBlock(Block block) { - if (block.Sources.Count != 1) - return block; - if (block.getOnlyTarget() == null) - return block; - if (block.Instructions.Count == 0) { - } - else if (block.Instructions.Count == 1 && block.Instructions[0].OpCode.Code == Code.Nop) { - } - else - return block; - return block.Sources[0]; - } - - static bool findTypeCode(Block block, out byte typeCode) { - block = fixBlock(block); - - var instrs = block.Instructions; - int numCeq = 0; - for (int i = instrs.Count - 1; i >= 0; i--) { - var instr = instrs[i]; - if (instr.OpCode.Code == Code.Ceq) { - numCeq++; - continue; - } - if (!DotNetUtils.isLdcI4(instr.Instruction)) - continue; - if (numCeq != 0 && numCeq != 2) - continue; - - typeCode = (byte)DotNetUtils.getLdcI4Value(instr.Instruction); - return true; - } - typeCode = 0; - return false; - } - EmbeddedResource findResource(MethodDefinition method) { return DotNetUtils.getResource(module, DotNetUtils.getCodeStrings(method)) as EmbeddedResource; } - public object decryptInt32(MethodDefinition caller, uint magic) { - byte typeCode; - var data = decryptData(caller, magic, out typeCode); - if (typeCode != int32Type) - return null; - if (data.Length != 4) - throw new ApplicationException("Invalid data length"); - return BitConverter.ToInt32(data, 0); - } - - public object decryptInt64(MethodDefinition caller, uint magic) { - byte typeCode; - var data = decryptData(caller, magic, out typeCode); - if (typeCode != int64Type) - return null; - if (data.Length != 8) - throw new ApplicationException("Invalid data length"); - return BitConverter.ToInt64(data, 0); - } - - public object decryptSingle(MethodDefinition caller, uint magic) { - byte typeCode; - var data = decryptData(caller, magic, out typeCode); - if (typeCode != singleType) - return null; - if (data.Length != 4) - throw new ApplicationException("Invalid data length"); - return BitConverter.ToSingle(data, 0); - } - - public object decryptDouble(MethodDefinition caller, uint magic) { - byte typeCode; - var data = decryptData(caller, magic, out typeCode); - if (typeCode != doubleType) - return null; - if (data.Length != 8) - throw new ApplicationException("Invalid data length"); - return BitConverter.ToDouble(data, 0); - } - - public string decryptString(MethodDefinition caller, uint magic) { - byte typeCode; - var data = decryptData(caller, magic, out typeCode); - if (typeCode != stringType) - return null; - return Encoding.UTF8.GetString(data); - } - - byte[] decryptData(MethodDefinition caller, uint magic, out byte typeCode) { - uint offs = calcHash(caller.MetadataToken.ToUInt32()) ^ magic; + protected override byte[] decryptData(DecrypterInfo info, MethodDefinition caller, object[] args, out byte typeCode) { + uint offs = info.calcHash(caller.MetadataToken.ToUInt32()) ^ (uint)args[0]; reader.BaseStream.Position = offs; typeCode = reader.ReadByte(); - if (typeCode != int32Type && typeCode != int64Type && - typeCode != singleType && typeCode != doubleType && - typeCode != stringType) + if (typeCode != info.int32Type && typeCode != info.int64Type && + typeCode != info.singleType && typeCode != info.doubleType && + typeCode != info.stringType) throw new ApplicationException("Invalid type code"); var encrypted = reader.ReadBytes(reader.ReadInt32()); - return decryptConstant(encrypted, offs); + return decryptConstant(info, encrypted, offs); } - byte[] decryptConstant(byte[] encrypted, uint offs) { + byte[] decryptConstant(DecrypterInfo info, byte[] encrypted, uint offs) { switch (version) { - case ConfuserVersion.v15_r60785_normal: return decryptConstant_v15_r60785_normal(encrypted, offs); - case ConfuserVersion.v15_r60785_dynamic: return decryptConstant_v15_r60785_dynamic(encrypted, offs); - case ConfuserVersion.v17_r73404_normal: return decryptConstant_v17_r73404_normal(encrypted, offs); - case ConfuserVersion.v17_r73740_dynamic: return decryptConstant_v17_r73740_dynamic(encrypted, offs); - case ConfuserVersion.v17_r73764_dynamic: return decryptConstant_v17_r73740_dynamic(encrypted, offs); - case ConfuserVersion.v17_r73764_native: return decryptConstant_v17_r73764_native(encrypted, offs); - case ConfuserVersion.v17_r73822_normal: return decryptConstant_v17_r73404_normal(encrypted, offs); - case ConfuserVersion.v17_r73822_dynamic: return decryptConstant_v17_r73740_dynamic(encrypted, offs); - case ConfuserVersion.v17_r73822_native: return decryptConstant_v17_r73764_native(encrypted, offs); + case ConfuserVersion.v15_r60785_normal: return decryptConstant_v15_r60785_normal(info, encrypted, offs); + case ConfuserVersion.v15_r60785_dynamic: return decryptConstant_v15_r60785_dynamic(info, encrypted, offs); + case ConfuserVersion.v17_r73404_normal: return decryptConstant_v17_r73404_normal(info, encrypted, offs); + case ConfuserVersion.v17_r73740_dynamic: return decryptConstant_v17_r73740_dynamic(info, encrypted, offs); + case ConfuserVersion.v17_r73764_dynamic: return decryptConstant_v17_r73740_dynamic(info, encrypted, offs); + case ConfuserVersion.v17_r73764_native: return decryptConstant_v17_r73764_native(info, encrypted, offs); + case ConfuserVersion.v17_r73822_normal: return decryptConstant_v17_r73404_normal(info, encrypted, offs); + case ConfuserVersion.v17_r73822_dynamic: return decryptConstant_v17_r73740_dynamic(info, encrypted, offs); + case ConfuserVersion.v17_r73822_native: return decryptConstant_v17_r73764_native(info, encrypted, offs); default: throw new ApplicationException("Invalid version"); } } - byte[] decryptConstant_v15_r60785_normal(byte[] encrypted, uint offs) { - var rand = new Random((int)(key0 ^ offs)); + byte[] decryptConstant_v15_r60785_normal(DecrypterInfo info, byte[] encrypted, uint offs) { + var rand = new Random((int)(info.key0 ^ offs)); var decrypted = new byte[encrypted.Length]; rand.NextBytes(decrypted); for (int i = 0; i < decrypted.Length; i++) @@ -486,8 +207,8 @@ namespace de4dot.code.deobfuscators.Confuser { return decrypted; } - byte[] decryptConstant_v15_r60785_dynamic(byte[] encrypted, uint offs) { - var instrs = decryptMethod.Body.Instructions; + byte[] decryptConstant_v15_r60785_dynamic(DecrypterInfo info, byte[] encrypted, uint offs) { + var instrs = info.decryptMethod.Body.Instructions; int startIndex = getDynamicStartIndex_v15_r60785(instrs); int endIndex = getDynamicEndIndex_v15_r60785(instrs, startIndex); if (endIndex < 0) @@ -530,8 +251,8 @@ namespace de4dot.code.deobfuscators.Confuser { return -1; } - byte[] decryptConstant_v17_r73404_normal(byte[] encrypted, uint offs) { - return ConfuserUtils.decrypt(key0 ^ offs, encrypted); + byte[] decryptConstant_v17_r73404_normal(DecrypterInfo info, byte[] encrypted, uint offs) { + return ConfuserUtils.decrypt(info.key0 ^ offs, encrypted); } static VariableDefinition getDynamicLocal_v17_r73740(MethodDefinition method) { @@ -596,17 +317,17 @@ namespace de4dot.code.deobfuscators.Confuser { return -1; } - byte[] decryptConstant_v17_r73740_dynamic(byte[] encrypted, uint offs) { - var local = getDynamicLocal_v17_r73740(decryptMethod); + byte[] decryptConstant_v17_r73740_dynamic(DecrypterInfo info, byte[] encrypted, uint offs) { + var local = getDynamicLocal_v17_r73740(info.decryptMethod); if (local == null) throw new ApplicationException("Could not find local"); - int endIndex = getDynamicEndIndex_v17_r73740(decryptMethod, local); - int startIndex = getDynamicStartIndex_v17_r73740(decryptMethod, endIndex); + int endIndex = getDynamicEndIndex_v17_r73740(info.decryptMethod, local); + int startIndex = getDynamicStartIndex_v17_r73740(info.decryptMethod, endIndex); if (startIndex < 0) throw new ApplicationException("Could not find start/end index"); - var constReader = new ConstantsReader(decryptMethod); + var constReader = new ConstantsReader(info.decryptMethod); return decrypt(encrypted, magic => { constReader.setConstantInt32(local, magic); int index = startIndex, result; @@ -616,9 +337,9 @@ namespace de4dot.code.deobfuscators.Confuser { }); } - byte[] decryptConstant_v17_r73764_native(byte[] encrypted, uint offs) { + byte[] decryptConstant_v17_r73764_native(DecrypterInfo info, byte[] encrypted, uint offs) { var x86Emu = new x86Emulator(new PeImage(fileData)); - return decrypt(encrypted, magic => (byte)x86Emu.emulate((uint)nativeMethod.RVA, magic)); + return decrypt(encrypted, magic => (byte)x86Emu.emulate((uint)info.nativeMethod.RVA, magic)); } byte[] decrypt(byte[] encrypted, Func decryptFunc) { @@ -631,36 +352,5 @@ namespace de4dot.code.deobfuscators.Confuser { return decrypted; } - - uint calcHash(uint x) { - uint h0 = key1 ^ x; - uint h1 = key2; - uint h2 = key3; - for (uint i = 1; i <= 64; i++) { - h0 = (h0 << 8) | (h0 >> 24); - uint n = h0 & 0x3F; - if (n >= 0 && n < 16) { - h1 |= ((byte)(h0 >> 8) & (h0 >> 16)) ^ (byte)~h0; - h2 ^= (h0 * i + 1) & 0xF; - h0 += (h1 | h2) ^ key0; - } - else if (n >= 16 && n < 32) { - h1 ^= ((h0 & 0x00FF00FF) << 8) ^ (ushort)((h0 >> 8) | ~h0); - h2 += (h0 * i) & 0x1F; - h0 |= (h1 + ~h2) & key0; - } - else if (n >= 32 && n < 48) { - h1 += (byte)(h0 | (h0 >> 16)) + (~h0 & 0xFF); - h2 -= ~(h0 + n) % 48; - h0 ^= (h1 % h2) | key0; - } - else if (n >= 48 && n < 64) { - h1 ^= ((byte)(h0 >> 16) | ~(h0 & 0xFF)) * (~h0 & 0x00FF0000); - h2 += (h0 ^ (i - 1)) % n; - h0 -= ~(h1 ^ h2) + key0; - } - } - return h0; - } } } diff --git a/de4dot.code/deobfuscators/Confuser/Deobfuscator.cs b/de4dot.code/deobfuscators/Confuser/Deobfuscator.cs index 53c1e57f..6ae257a3 100644 --- a/de4dot.code/deobfuscators/Confuser/Deobfuscator.cs +++ b/de4dot.code/deobfuscators/Confuser/Deobfuscator.cs @@ -428,30 +428,38 @@ namespace de4dot.code.deobfuscators.Confuser { bool hasInitializedConstantsDecrypter15 = false; void initializeConstantsDecrypter15() { - if (hasInitializedConstantsDecrypter15 || (constantsDecrypterV15 == null || !constantsDecrypterV15.Detected)) + initialize(constantsDecrypterV15, ref hasInitializedConstantsDecrypter15); + } + + void initialize(ConstantsDecrypterBase constDecrypter, ref bool hasInitialized) { + if (hasInitialized || (constDecrypter == null || !constDecrypter.Detected)) return; hasInitializedConstantsDecrypter15 = true; decryptResources(); - constantsDecrypterV15.initialize(); + constDecrypter.initialize(); int32ValueInliner = new Int32ValueInliner(); int64ValueInliner = new Int64ValueInliner(); singleValueInliner = new SingleValueInliner(); doubleValueInliner = new DoubleValueInliner(); - staticStringInliner.add(constantsDecrypterV15.Method, (method, gim, args) => constantsDecrypterV15.decryptString(staticStringInliner.Method, (uint)args[0])); - int32ValueInliner.add(constantsDecrypterV15.Method, (method, gim, args) => constantsDecrypterV15.decryptInt32(int32ValueInliner.Method, (uint)args[0])); - int64ValueInliner.add(constantsDecrypterV15.Method, (method, gim, args) => constantsDecrypterV15.decryptInt64(int64ValueInliner.Method, (uint)args[0])); - singleValueInliner.add(constantsDecrypterV15.Method, (method, gim, args) => constantsDecrypterV15.decryptSingle(singleValueInliner.Method, (uint)args[0])); - doubleValueInliner.add(constantsDecrypterV15.Method, (method, gim, args) => constantsDecrypterV15.decryptDouble(doubleValueInliner.Method, (uint)args[0])); + foreach (var info in constDecrypter.DecrypterInfos) { + staticStringInliner.add(info.decryptMethod, (method, gim, args) => constDecrypter.decryptString(staticStringInliner.Method, method, args)); + int32ValueInliner.add(info.decryptMethod, (method, gim, args) => constDecrypter.decryptInt32(int32ValueInliner.Method, method, args)); + int64ValueInliner.add(info.decryptMethod, (method, gim, args) => constDecrypter.decryptInt64(int64ValueInliner.Method, method, args)); + singleValueInliner.add(info.decryptMethod, (method, gim, args) => constDecrypter.decryptSingle(singleValueInliner.Method, method, args)); + doubleValueInliner.add(info.decryptMethod, (method, gim, args) => constDecrypter.decryptDouble(doubleValueInliner.Method, method, args)); + } int32ValueInliner.RemoveUnbox = true; int64ValueInliner.RemoveUnbox = true; singleValueInliner.RemoveUnbox = true; doubleValueInliner.RemoveUnbox = true; DeobfuscatedFile.stringDecryptersAdded(); - addFieldsToBeRemoved(constantsDecrypterV15.Fields, "Constants decrypter field"); - addMethodToBeRemoved(constantsDecrypterV15.Method, "Constants decrypter method"); - addMethodToBeRemoved(constantsDecrypterV15.NativeMethod, "Constants decrypter native method"); - addResourceToBeRemoved(constantsDecrypterV15.Resource, "Encrypted constants"); + addFieldsToBeRemoved(constDecrypter.Fields, "Constants decrypter field"); + foreach (var info in constDecrypter.DecrypterInfos) { + addMethodToBeRemoved(info.decryptMethod, "Constants decrypter method"); + addMethodToBeRemoved(info.nativeMethod, "Constants decrypter native method"); + } + addResourceToBeRemoved(constDecrypter.Resource, "Encrypted constants"); } void decryptResources() {