monocul.us/de4dot-cex
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Update CS detector and support an old string decrypter

Browse Source
This commit is contained in:
de4dot 2012-04-26 01:16:08 +02:00
parent 60c98cc944
commit d84d2e6a6c
2 changed files with 64 additions and 62 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

123
de4dot.code/deobfuscators/CliSecure/CliSecureRtType.cs
View File

@ -80,65 +80,37 @@ namespace de4dot.code.deobfuscators.CliSecure {
return;
if (find2())
return;
if (findOld())
return;
findNativeCode();
}
static readonly string[] requiredFields1 = new string[] {
"System.Boolean",
};
static readonly string[] requiredFields2 = new string[] {
"System.Boolean",
"System.Reflection.Assembly",
};
static readonly string[] requiredFields3 = new string[] {
"System.Boolean",
"System.Reflection.Assembly",
"System.Byte[]",
};
bool find2() {
foreach (var type in module.Types) {
if (type.Namespace != "")
continue;
var typeName = type.FullName;
MethodDefinition cs = null;
MethodDefinition initialize = null;
MethodDefinition postInitialize = null;
MethodDefinition load = null;
int methods = 0;
foreach (var method in type.Methods) {
if (method.FullName == "System.String " + typeName + "::cs(System.String)") {
cs = method;
methods++;
}
else if (method.FullName == "System.Void " + typeName + "::Initialize()") {
initialize = method;
methods++;
}
else if (method.FullName == "System.Void " + typeName + "::PostInitialize()") {
postInitialize = method;
methods++;
}
else if (method.FullName == "System.IntPtr " + typeName + "::Load()") {
load = method;
methods++;
}
}
if (methods == 0 || (methods == 1 && initialize != null))
continue;
stringDecrypterMethod = cs;
initializeMethod = initialize;
postInitializeMethod = postInitialize;
loadMethod = load;
cliSecureRtType = type;
return true;
}
return false;
}
bool findOld() {
foreach (var cctor in DeobUtils.getInitCctors(module, 3)) {
foreach (var calledMethod in DotNetUtils.getCalledMethods(module, cctor)) {
var type = calledMethod.DeclaringType;
if (!hasPinvokeMethod(type, "_Initialize"))
if (type.IsPublic)
continue;
if (!hasPinvokeMethod(type, "_Initialize64"))
var fieldTypes = new FieldTypes(type);
if (!fieldTypes.exactly(requiredFields1) && !fieldTypes.exactly(requiredFields2) && !fieldTypes.exactly(requiredFields3))
continue;
if (!hasInitializeMethod(type, "_Initialize"))
continue;
stringDecrypterMethod = findStringDecrypterMethod(type);
initializeMethod = calledMethod;
postInitializeMethod = findMethod(type, "System.Void", "PostInitialize", "()");
loadMethod = findMethod(type, "System.IntPtr", "Load", "()");
cliSecureRtType = type;
return true;
}
@ -147,6 +119,47 @@ namespace de4dot.code.deobfuscators.CliSecure {
return false;
}
static MethodDefinition findStringDecrypterMethod(TypeDefinition type) {
foreach (var method in type.Methods) {
if (method.Body == null || !method.IsStatic)
continue;
if (!DotNetUtils.isMethod(method, "System.String", "(System.String)"))
continue;
return method;
}
return null;
}
static MethodDefinition findMethod(TypeDefinition type, string returnType, string name, string parameters) {
var methodName = returnType + " " + type.FullName + "::" + name + parameters;
foreach (var method in type.Methods) {
if (method.Body == null || !method.IsStatic)
continue;
if (method.FullName != methodName)
continue;
return method;
}
return null;
}
static bool hasInitializeMethod(TypeDefinition type, string name) {
var method = DotNetUtils.getPInvokeMethod(type, name);
if (method == null)
return false;
if (method.Parameters.Count != 1)
return false;
if (method.Parameters[0].ParameterType.FullName != "System.IntPtr")
return false;
var retType = method.MethodReturnType.ReturnType.FullName;
if (retType != "System.Void" && retType != "System.Int32")
return false;
return true;
}
bool findNativeCode() {
if ((module.Attributes & ModuleAttributes.ILOnly) != 0)
return false;
@ -157,20 +170,8 @@ namespace de4dot.code.deobfuscators.CliSecure {
}
}
static bool hasPinvokeMethod(TypeDefinition type, string methodName) {
if (type == null)
return false;
foreach (var method in type.Methods) {
if (method.PInvokeInfo == null)
continue;
if (method.PInvokeInfo.EntryPoint == methodName)
return true;
}
return false;
}
public bool isAtLeastVersion50() {
return hasPinvokeMethod(cliSecureRtType, "LoadLibraryA");
return DotNetUtils.hasPinvokeMethod(cliSecureRtType, "LoadLibraryA");
}
}
}

3
de4dot.code/deobfuscators/CliSecure/StringDecrypter.cs
View File

@ -29,7 +29,7 @@ namespace de4dot.code.deobfuscators.CliSecure {
byte[] stringDecrypterKey;
public bool Detected {
get { return stringDecrypterKey != null; }
get { return stringDecrypterMethod != null; }
}
public TypeDefinition Type {
@ -57,6 +57,7 @@ namespace de4dot.code.deobfuscators.CliSecure {
}
public void find() {
stringDecrypterKey = new byte[1] { 0xFF };
foreach (var type in module.Types) {
if (type.FullName == "<D234>" || type.FullName == "<ClassD234>") {
stringDecrypterType = type;