1. 起因

写代码的时候，需要动态加载DLL，这是一个非常非常常规的操作对吧。然而在开发的时候表现的一切正常，但是打包后，在别的机子上死活加载不到dll。

2. 问题原因

对于这个问题常见的原因无非就以下几个：

1. DLL生成的有问题
2. 加载路径写的不对
3. 程序的权限不够

我这里遇到的是权限不够，所以我以管理员权限运行程序，我以为我终于要解决问题的了，but给我返回了个126(无法找到指定模块)…
苦思冥想哪里不对，depends工具了(解析dll的依赖)，ProcessMonitor工具也用了(查看运行的程序所加载的模块)，还是一头雾水(我的头发啊！！！)。最后了解到Widnows提权的事情，通过Windows提权解决了126问题

3. 解决

3.1 C++ 版

BOOL SetPrivilege()
{
    
	HANDLE hToken;
	TOKEN_PRIVILEGES NewState;
	LUID luidPrivilegeLUID;

	if (!OpenProcessToken(GetCurrentProcess(), TOKEN_ADJUST_PRIVILEGES, &hToken) || 
		!LookupPrivilegeValue(NULL, SE_DEBUG_NAME, &luidPrivilegeLUID))
	{
    
		return FALSE;
	}
	NewState.PrivilegeCount = 1;
	NewState.Privileges[0].Luid = luidPrivilegeLUID;
	NewState.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
	if (!AdjustTokenPrivileges(hToken, FALSE, &NewState, NULL, NULL, NULL))
	{
    
		return FALSE;
	}
	return TRUE;
}


int main() {
    
	SetPrivilege();
	HMODULE hModule = LoadLibraryA("xxx.dll");
	if (hModule)
	{
    
		//FARPROC func = GetProcAddress(hModule, "fuck");
		FARPROC func = GetProcAddress(hModule, "fuck");
		printf("load function Ptr %p\n", func);
		FreeLibrary(hModule);
		system("pause");
		return 0;
	}
	CHAR szBuf[128];

	LPVOID lpMsgBuf;
	DWORD dw = GetLastError();
	FormatMessage(
		FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,
		NULL,
		dw,
		MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
		(LPTSTR)&lpMsgBuf,
		0, NULL);
	MessageBox(NULL, (LPCTSTR)lpMsgBuf, (LPCTSTR)(""), MB_OK | MB_ICONINFORMATION);
	printf("load failed\n");
	system("pause");
	return 0;
}

3.2 C#版

internal class WinAPI
{
    

	/// <summary>
	/// 令牌特定访问权限
	/// </summary>
	internal enum TSAR
	{
    
		TOKEN_ADJUST_PRIVILEGES = 0x0020,

	}

	/// <summary>
	/// 权限相关数据结构
	/// </summary>
	internal enum PRDS
	{
    
		SE_PRIVILEGE_ENABLED = 0x00000002
	}

	// NT Defined Privileges(NT 定义的特权)
	internal static string SE_DEBUG_NAME = "SeDebugPrivilege";

	[DllImport("kernel32.dll")]
	internal extern static IntPtr LoadLibrary(string path);

	[DllImport("kernel32.dll")]
	internal extern static IntPtr GetProcAddress(IntPtr lib, string funcName);

	[DllImport("kernel32.dll")]
	internal extern static bool FreeLibrary(IntPtr lib);

	[DllImport("kernel32.dll")]
	internal static extern IntPtr GetStdHandle(int nStdHandle);

	[DllImport("kernel32.dll")]
	internal static extern int GetLastError();

	[DllImport("user32", EntryPoint = "CallWindowProc")]
	internal static extern int CallWindowProc(IntPtr lpPrevWndFunc, int hwnd, int MSG, int wParam, int lParam);


	[DllImport("kernel32.dll")]
	internal static extern IntPtr GetCurrentProcess();

	[StructLayout(LayoutKind.Sequential)]
	internal struct LUID
	{
    
		public int LowPart;
		public uint HighPart;
	}

	[StructLayout(LayoutKind.Sequential)]
	internal struct LUID_AND_ATTRIBUTES
	{
    
		public LUID Luid;
		public uint Attributes;
	}

	[StructLayout(LayoutKind.Sequential)]
	internal struct TOKEN_PRIVILEGES
	{
    
		public int PrivilegeCount;
		[MarshalAs(UnmanagedType.ByValArray, SizeConst = 1, ArraySubType = UnmanagedType.Struct)]
		public LUID_AND_ATTRIBUTES[] Privileges;
	}

	[DllImport("Advapi32.dll")]
	[return: MarshalAs(UnmanagedType.Bool)]
	internal static extern bool OpenProcessToken(IntPtr ProcessHandle, uint DesiredAccesss, out IntPtr TokenHandle);

	[DllImport("advapi32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
	[return: MarshalAs(UnmanagedType.Bool)]
	internal static extern bool AdjustTokenPrivileges(IntPtr TokenHandle, [MarshalAs(UnmanagedType.Bool)] bool DisableAllPrivileges, [MarshalAs(UnmanagedType.Struct)] ref TOKEN_PRIVILEGES NewState, uint BufferLength, IntPtr PreviousState, uint ReturnLength);

	[DllImport("advapi32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
	[return: MarshalAs(UnmanagedType.Bool)]
	public static extern bool LookupPrivilegeValue(string lpSystemName, string lpName, [MarshalAs(UnmanagedType.Struct)] ref LUID lpLuid);

}
#endregion
public class LoadDLLTest
{
    
	IntPtr DllLib;//DLL文件名柄   
	#region 构造函数   
	public LoadDLLTest(string dllpath)
	{
    
		int ret = 0;
		// 提权
		IntPtr hToken = IntPtr.Zero;
		WinAPI.TOKEN_PRIVILEGES NewState = new WinAPI.TOKEN_PRIVILEGES();
		WinAPI.LUID luidPrivilegeLUID = new WinAPI.LUID();

		//获取进程令牌
		if (!WinAPI.OpenProcessToken(WinAPI.GetCurrentProcess(), (uint)WinAPI.TSAR.TOKEN_ADJUST_PRIVILEGES, out hToken) || 
			!WinAPI.LookupPrivilegeValue(null, WinAPI.SE_DEBUG_NAME,ref luidPrivilegeLUID))
		{
    
			return;
		}
		NewState.PrivilegeCount = 1;
		NewState.Privileges = new WinAPI.LUID_AND_ATTRIBUTES[1];
		NewState.Privileges[0].Luid = luidPrivilegeLUID;
		NewState.Privileges[0].Attributes = (uint)WinAPI.PRDS.SE_PRIVILEGE_ENABLED;
		//提示进程权限，注意该函数也可以改变线程的权限，如果hToken指向一个线程的令牌 
		if (!WinAPI.AdjustTokenPrivileges(hToken, false, ref NewState, 0, IntPtr.Zero, 0))
		{
    
			return;
		}

		DllLib = WinAPI.LoadLibrary(dllpath);
		if (DllLib == IntPtr.Zero)
		{
    
			ret = WinAPI.GetLastError();
		}
	}
	#endregion
	/// <summary>   
	/// 析构函数   
	/// </summary>   
	~LoadDLLTest()
	{
    
		if (DllLib != IntPtr.Zero)
		{
    
			// 释放名柄
			WinAPI.FreeLibrary(DllLib);
		}
	}

	/// <summary>   
	/// 获取DLL中一个方法的委托   
	/// </summary>   
	/// <param name="methodname"></param>   
	/// <param name="methodtype"></param>   
	/// <returns></returns>   
	public Delegate InvokeMethod(string methodname, Type methodtype)
	{
    
		if (DllLib == IntPtr.Zero)
			return null;

		IntPtr MethodPtr = WinAPI.GetProcAddress(DllLib, methodname);

		if (MethodPtr == IntPtr.Zero)
			return null;

		return (Delegate)Marshal.GetDelegateForFunctionPointer(MethodPtr, methodtype);
	}

	// 声明此方法的一个委托
	public delegate bool TestFunction([MarshalAs(UnmanagedType.LPStr)] string para1,
		[MarshalAs(UnmanagedType.LPStr)] string para2,
		[MarshalAs(UnmanagedType.LPArray, ArraySubType = UnmanagedType.LPStr)] string[] knockIp,
		[MarshalAs(UnmanagedType.I4)] int para3);

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