x64 DLL注入器适配用户输入DLL路径失败，寻求技术帮助

Hey there, let's break down why your DLL path input via std::cin might be causing issues with your x64 injector—since your process lookup works, we can narrow this down to path handling specifics.

1. Compile Errors: Wide vs. Multi-Byte Character Mismatch #

Most Windows injection APIs (like CreateRemoteThreadW, VirtualAllocExW) use wide-character strings (wchar_t*). If you're reading a standard std::string with std::cin and passing it directly to these wide-character functions, you'll get compile errors immediately.

Fixes:

• Read directly into a wide string with std::wcin:

  std::wstring dllPath;
  std::wcout << L"Enter DLL path: ";
  std::wcin >> dllPath;
  

• Or convert a multi-byte std::string to a wide string:

  std::string dllPathStr;
  std::cin >> dllPathStr;
  
  // Convert to wide character
  int wideBufferSize = MultiByteToWideChar(CP_UTF8, 0, dllPathStr.c_str(), -1, nullptr, 0);
  std::wstring dllPath(wideBufferSize, 0);
  MultiByteToWideChar(CP_UTF8, 0, dllPathStr.c_str(), -1, dllPath.data(), wideBufferSize);
  

2. Injection Fails (No Compile Errors): Path Format or Completeness Issues #

If your code compiles but injection doesn't work, these are the most likely culprits:

• Truncated paths from space-separated input: std::cin >> stops reading at the first space. If your DLL path has spaces (e.g., C:\Program Files\MyInject.dll), you'll only get C:\Program as the path.
  Fix: Use std::getline to read the full path:

  std::string dllPathStr;
  std::cout << "Enter DLL path: ";
  // If you used std::cin earlier (for process name), clear leftover newline first:
  std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n');
  std::getline(std::cin, dllPathStr);
  

• Relative path ambiguity: If the user enters a relative path (e.g., ./MyDLL.dll), the target process's working directory might not match your injector's, so it can't find the DLL.
  Fix: Convert the input to an absolute path with GetFullPathNameW:

  std::wstring dllPath;
  std::wcin >> dllPath;
  WCHAR fullPath[MAX_PATH] = {0};
  GetFullPathNameW(dllPath.c_str(), MAX_PATH, fullPath, nullptr);
  dllPath = fullPath;
  

• Inaccessible DLL file: The target process might not have read permissions for the DLL's directory. Add a pre-check to validate the path:

  if (GetFileAttributesW(dllPath.c_str()) == INVALID_FILE_ATTRIBUTES) {
      std::wcerr << L"Error: DLL file not found or inaccessible!" << std::endl;
      return 1;
  }
  

3. x64-Specific Checks #

• Ensure your injector is compiled as x64—cross-architecture injection (x86 injector → x64 process) will silently fail.
• Use SIZE_T instead of DWORD for memory size parameters in VirtualAllocEx—x64 uses 64-bit memory addresses, so DWORD will truncate values and cause failures.

Quick Debug Tip #

When injection fails, call GetLastError() immediately after the failing API call. The error code will tell you exactly what's wrong (e.g., error 2 = file not found, error 5 = access denied).

内容的提问来源于stack exchange，提问作者Johnny Code