public static byte[] AssembleCode(x86CodeGen codeGen, x86Register reg)
{
var stream = new MemoryStream();
using (var writer = new BinaryWriter(stream)) {
/*
* mov eax, esp
* push ebx
* push edi
* push esi
* sub eax, esp
* cmp eax, 24 ; determine the bitness of platform
* je n
* mov eax, [esp + 4] ; 32 bits => argument in stack
* push eax
* jmp z
* n: push ecx ; 64 bits => argument in register
* z: XXX
* pop esi
* pop edi
* pop ebx
* pop ret
*
*/
writer.Write(new byte[] { 0x89, 0xe0 });
writer.Write(new byte[] { 0x53 });
writer.Write(new byte[] { 0x57 });
writer.Write(new byte[] { 0x56 });
writer.Write(new byte[] { 0x29, 0xe0 });
writer.Write(new byte[] { 0x83, 0xf8, 0x18 });
writer.Write(new byte[] { 0x74, 0x07 });
writer.Write(new byte[] { 0x8b, 0x44, 0x24, 0x10 });
writer.Write(new byte[] { 0x50 });
writer.Write(new byte[] { 0xeb, 0x01 });
writer.Write(new byte[] { 0x51 });
foreach (x86Instruction i in codeGen.Instructions)
writer.Write(i.Assemble());
if (reg != x86Register.EAX)
writer.Write(x86Instruction.Create(x86OpCode.MOV, new x86RegisterOperand(x86Register.EAX), new x86RegisterOperand(reg)).Assemble());
writer.Write(new byte[] { 0x5e });
writer.Write(new byte[] { 0x5f });
writer.Write(new byte[] { 0x5b });
writer.Write(new byte[] { 0xc3 });
}
return stream.ToArray();
}
private void Compile(RPContext ctx, out Func<int, int> expCompiled, out MethodDef native)
{
var var = new Variable("{VAR}");
var result = new Variable("{RESULT}");
CorLibTypeSig int32 = ctx.Module.CorLibTypes.Int32;
native = new MethodDefUser(ctx.Context.Registry.GetService<INameService>().RandomName(), MethodSig.CreateStatic(int32, int32), MethodAttributes.PinvokeImpl | MethodAttributes.PrivateScope | MethodAttributes.Static);
native.ImplAttributes = MethodImplAttributes.Native | MethodImplAttributes.Unmanaged | MethodImplAttributes.PreserveSig;
ctx.Module.GlobalType.Methods.Add(native);
ctx.Context.Registry.GetService<IMarkerService>().Mark(native);
ctx.Context.Registry.GetService<INameService>().SetCanRename(native, false);
x86Register? reg;
var codeGen = new x86CodeGen();
Expression expression, inverse;
do {
ctx.DynCipher.GenerateExpressionPair(
ctx.Random,
new VariableExpression { Variable = var }, new VariableExpression { Variable = result },
ctx.Depth, out expression, out inverse);
reg = codeGen.GenerateX86(inverse, (v, r) => { return new[] { x86Instruction.Create(x86OpCode.POP, new x86RegisterOperand(r)) }; });
} while (reg == null);
byte[] code = CodeGenUtils.AssembleCode(codeGen, reg.Value);
expCompiled = new DMCodeGen(typeof(int), new[] { Tuple.Create("{VAR}", typeof(int)) })
.GenerateCIL(expression)
.Compile<Func<int, int>>();
nativeCodes.Add(Tuple.Create(native, code, (MethodBody)null));
if (!addedHandler) {
ctx.Context.CurrentModuleWriterListener.OnWriterEvent += InjectNativeCode;
addedHandler = true;
}
}
public void Compile(CFContext ctx) {
var var = new Variable("{VAR}");
var result = new Variable("{RESULT}");
CorLibTypeSig int32 = ctx.Method.Module.CorLibTypes.Int32;
native = new MethodDefUser(ctx.Context.Registry.GetService<INameService>().RandomName(), MethodSig.CreateStatic(int32, int32), MethodAttributes.PinvokeImpl | MethodAttributes.PrivateScope | MethodAttributes.Static);
native.ImplAttributes = MethodImplAttributes.Native | MethodImplAttributes.Unmanaged | MethodImplAttributes.PreserveSig;
// Attempt to improve performance --- failed with StackOverflowException... :/
//var suppressAttr = ctx.Method.Module.CorLibTypes.GetTypeRef("System.Security", "SuppressUnmanagedCodeSecurityAttribute").ResolveThrow();
//native.CustomAttributes.Add(new CustomAttribute((MemberRef)ctx.Method.Module.Import(suppressAttr.FindDefaultConstructor())));
//native.HasSecurity = true;
ctx.Method.Module.GlobalType.Methods.Add(native);
ctx.Context.Registry.GetService<IMarkerService>().Mark(native, ctx.Protection);
ctx.Context.Registry.GetService<INameService>().SetCanRename(native, false);
x86Register? reg;
var codeGen = new x86CodeGen();
do {
ctx.DynCipher.GenerateExpressionPair(
ctx.Random,
new VariableExpression { Variable = var }, new VariableExpression { Variable = result },
ctx.Depth, out expression, out inverse);
reg = codeGen.GenerateX86(inverse, (v, r) => { return new[] { x86Instruction.Create(x86OpCode.POP, new x86RegisterOperand(r)) }; });
} while (reg == null);
code = CodeGenUtils.AssembleCode(codeGen, reg.Value);
expCompiled = new DMCodeGen(typeof(int), new[] { Tuple.Create("{VAR}", typeof(int)) })
.GenerateCIL(expression)
.Compile<Func<int, int>>();
ctx.Context.CurrentModuleWriterListener.OnWriterEvent += InjectNativeCode;
}
