Question

我的应用运行时requestedExecutionLevel设置为highestAvailable。

如何运行一个未提升的流程？

我尝试了以下但是没有用：

Process.Start(new ProcessStartInfo {FileName = "foo.exe", Verb = "open"})

我尝试使用以下信任级别来使用Win32 API启动我的进程，但它们都没有正常工作：

0
1260: This program is blocked by group policy. For more information, contact your system administrator.

0x1000
The application was unable to start correctly (0xc0000142). Click OK to close the application. 

0x10000
Process starts then hangs

0x20000
All options are not available

0x40000
Runs as admin

如果我从提升的应用中运行tskill foo，它会以正确的权限重新启动foo。

我需要的是一种解决方案，我无需指定信任级别。该过程应自动以正确的信任级别开始，就像tskill工具在正确的信任级别重新启动foo.exe一样。用户选择并运行foo.exe，因此它可以是任何内容。

如果我能以某种方式获得进程的信任级别，我可以轻松地执行此操作，因为当我的应用程序可以捕获其信任级别时foo.exe运行。

Answer 1

Win32安全管理功能提供了使用普通用户权限创建受限令牌的功能;使用令牌，您可以调用CreateProcessAsUser以使用该令牌运行进程。以下是将cmd.exe作为普通用户运行的概念验证，无论该进程是否在提升的上下文中运行。

// Initialize variables.  
IntPtr hSaferLevel, hToken;
STARTUPINFO si = default(STARTUPINFO);
SECURITY_ATTRIBUTES processAttributes = default(SECURITY_ATTRIBUTES);
SECURITY_ATTRIBUTES threadAttributes = default(SECURITY_ATTRIBUTES);
PROCESS_INFORMATION pi;
si.cb = Marshal.SizeOf(si);

// The process to start (for demonstration, cmd.exe)
string ProcessName = Path.Combine(
    Environment.GetFolderPath(Environment.SpecialFolder.System),
    "cmd.exe");

// Create the restricted token info
if (!SaferCreateLevel(
     SaferScopes.User,
     SaferLevels.NormalUser, // Program will execute as a normal user
     1, // required
     out hSaferLevel,
     IntPtr.Zero))
         throw new Win32Exception(Marshal.GetLastWin32Error());

// From the level create a token
if (!SaferComputeTokenFromLevel(
     hSaferLevel,
     IntPtr.Zero,
     out hToken,
     SaferComputeTokenFlags.None,
     IntPtr.Zero))
         throw new Win32Exception(Marshal.GetLastWin32Error());

// Run the process with the restricted token
if (!CreateProcessAsUser(
     hToken,
     ProcessName,
     null, ref processAttributes, ref threadAttributes,
     true, 0, IntPtr.Zero, null,
     ref si, out pi))
         throw new Win32Exception(Marshal.GetLastWin32Error());

 // Cleanup
 if (!CloseHandle(pi.hProcess))
     throw new Win32Exception(Marshal.GetLastWin32Error());
 if (!CloseHandle(pi.hThread))
     throw new Win32Exception(Marshal.GetLastWin32Error());
 if (!SaferCloseLevel(hSaferLevel))
     throw new Win32Exception(Marshal.GetLastWin32Error());

此方法使用以下Win32函数：

SaferIdentifyLevel表示身份级别（有限，正常或提升）。将levelId设置为SAFER_LEVELID_NORMALUSER（0x20000）可以提供正常的用户级别。
SaferComputeTokenFromLevel为提供的级别创建令牌。将NULL传递给InAccessToken参数将使用当前线程的标识。
CreateProcessAsUser使用提供的令牌创建进程。由于会话已经是交互式的，因此大多数参数可以保持默认值。（第三个参数lpCommandLine可以作为字符串提供，以指定命令行。）
CloseHandle (Kernel32)和SaferCloseLevel释放已分配的内存。

最后，P / Invoke代码如下（主要从pinvoke.net复制）：

[Flags]
public enum SaferLevels : uint
{
    Disallowed = 0,
    Untrusted = 0x1000,
    Constrained = 0x10000,
    NormalUser = 0x20000,
    FullyTrusted = 0x40000
}

[Flags]
public enum SaferComputeTokenFlags : uint
{
    None = 0x0,
    NullIfEqual = 0x1,
    CompareOnly = 0x2,
    MakeIntert = 0x4,
    WantFlags = 0x8
}

[Flags]
public enum SaferScopes : uint
{
    Machine = 1,
    User = 2
}

[StructLayout(LayoutKind.Sequential)]
public struct SECURITY_ATTRIBUTES
{
    public int nLength;
    public IntPtr lpSecurityDescriptor;
    public int bInheritHandle;
}

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
struct STARTUPINFO
{
    public Int32 cb;
    public string lpReserved;
    public string lpDesktop;
    public string lpTitle;
    public Int32 dwX;
    public Int32 dwY;
    public Int32 dwXSize;
    public Int32 dwYSize;
    public Int32 dwXCountChars;
    public Int32 dwYCountChars;
    public Int32 dwFillAttribute;
    public Int32 dwFlags;
    public Int16 wShowWindow;
    public Int16 cbReserved2;
    public IntPtr lpReserved2;
    public IntPtr hStdInput;
    public IntPtr hStdOutput;
    public IntPtr hStdError;
}

[StructLayout(LayoutKind.Sequential)]
internal struct PROCESS_INFORMATION
{
    public IntPtr hProcess;
    public IntPtr hThread;
    public int dwProcessId;
    public int dwThreadId;
}


[DllImport("advapi32", SetLastError = true, CallingConvention = CallingConvention.StdCall)]
public static extern bool SaferComputeTokenFromLevel(IntPtr LevelHandle, IntPtr InAccessToken, out IntPtr OutAccessToken, int dwFlags, IntPtr lpReserved);

[DllImport("advapi32.dll", SetLastError = true, CharSet = CharSet.Auto)]
static extern bool CreateProcessAsUser(
    IntPtr hToken,
    string lpApplicationName,
    string lpCommandLine,
    ref SECURITY_ATTRIBUTES lpProcessAttributes,
    ref SECURITY_ATTRIBUTES lpThreadAttributes,
    bool bInheritHandles,
    uint dwCreationFlags,
    IntPtr lpEnvironment,
    string lpCurrentDirectory,
    ref STARTUPINFO lpStartupInfo,
    out PROCESS_INFORMATION lpProcessInformation); 

[DllImport("advapi32", SetLastError = true, CallingConvention = CallingConvention.StdCall)]
public static extern bool SaferCreateLevel(
    SaferScopes dwScopeId,
    SaferLevels dwLevelId,
    int OpenFlags,
    out IntPtr pLevelHandle,
    IntPtr lpReserved);

[DllImport("advapi32", SetLastError = true, CallingConvention = CallingConvention.StdCall)]
public static extern bool SaferCloseLevel(
    IntPtr pLevelHandle);

[DllImport("advapi32", SetLastError = true, CallingConvention = CallingConvention.StdCall)]
public static extern bool SaferComputeTokenFromLevel(
  IntPtr levelHandle,
  IntPtr inAccessToken,
  out IntPtr outAccessToken,
  SaferComputeTokenFlags dwFlags,
  IntPtr lpReserved
);

[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
static extern bool CloseHandle(IntPtr hObject);

Answer 2

我通过克隆Explorer的令牌获得了最佳结果，如下所示：

var shellWnd = WinAPI.GetShellWindow();
if (shellWnd == IntPtr.Zero)
    throw new Exception("Could not find shell window");

uint shellProcessId;
WinAPI.GetWindowThreadProcessId(shellWnd, out shellProcessId);

var hShellProcess = WinAPI.OpenProcess(0x00000400 /* QueryInformation */, false, shellProcessId);

var hShellToken = IntPtr.Zero;
if (!WinAPI.OpenProcessToken(hShellProcess, 2 /* TOKEN_DUPLICATE */, out hShellToken))
    throw new Win32Exception();

uint tokenAccess = 8 /*TOKEN_QUERY*/ | 1 /*TOKEN_ASSIGN_PRIMARY*/ | 2 /*TOKEN_DUPLICATE*/ | 0x80 /*TOKEN_ADJUST_DEFAULT*/ | 0x100 /*TOKEN_ADJUST_SESSIONID*/;
var hToken = IntPtr.Zero;
WinAPI.DuplicateTokenEx(hShellToken, tokenAccess, IntPtr.Zero, 2 /* SecurityImpersonation */, 1 /* TokenPrimary */, out hToken);

var pi = new WinAPI.PROCESS_INFORMATION();
var si = new WinAPI.STARTUPINFO();
si.cb = Marshal.SizeOf(si);
if (!WinAPI.CreateProcessWithTokenW(hToken, 0, null, cmdArgs, 0, IntPtr.Zero, null, ref si, out pi))
    throw new Win32Exception();

替代方法

最初我选择了drf的优秀答案，但稍微扩展了一下。如果上述（克隆资源管理器的令牌）不符合您的喜好，请继续阅读，但在最后看到问题。

当使用描述的drf方法时，该过程在没有管理访问权限的情况下启动，但仍具有高完整性级别。典型的未升级过程具有中等完整性级别。

试试这个：使用Process Hacker以这种方式查看流程的属性;您将看到PH认为该进程即使没有管理访问权限也会被提升。添加完整性列，您会看到它是“高”。

修复相当简单：使用SaferComputeTokenFromLevel后，我们需要将令牌完整性级别更改为“中”。执行此操作的代码可能如下所示（从MSDN sample转换而来）：

// Get the Medium Integrity SID
if (!WinAPI.ConvertStringSidToSid("S-1-16-8192", out pMediumIntegritySid))
    throw new Win32Exception();

// Construct a structure describing the token integrity level
var TIL = new TOKEN_MANDATORY_LABEL();
TIL.Label.Attributes = 0x00000020 /* SE_GROUP_INTEGRITY */;
TIL.Label.Sid = pMediumIntegritySid;
pTIL = Marshal.AllocHGlobal(Marshal.SizeOf<TOKEN_MANDATORY_LABEL>());
Marshal.StructureToPtr(TIL, pTIL, false);

// Modify the token
if (!WinAPI.SetTokenInformation(hToken, 25 /* TokenIntegrityLevel */, pTIL,
                                (uint) Marshal.SizeOf<TOKEN_MANDATORY_LABEL>()
                                + WinAPI.GetLengthSid(pMediumIntegritySid)))
    throw new Win32Exception();

唉，这仍然没有真正完全解决问题。该过程不具有管理访问权限;它不具有高完整性，但它仍然有一个标记为“提升”的标记。

这对你来说是否是一个问题我不知道，但这可能就是为什么我最终克隆了Explorer的令牌，如本回答开头所述。

这是我的完整源代码（修改过的drf的答案），在它的所有P / Invoke荣耀中：

var hSaferLevel = IntPtr.Zero;
var hToken = IntPtr.Zero;
var pMediumIntegritySid = IntPtr.Zero;
var pTIL = IntPtr.Zero;
var pi = new WinAPI.PROCESS_INFORMATION();
try
{
    var si = new WinAPI.STARTUPINFO();
    si.cb = Marshal.SizeOf(si);
    var processAttributes = new WinAPI.SECURITY_ATTRIBUTES();
    var threadAttributes = new WinAPI.SECURITY_ATTRIBUTES();
    var args = CommandRunner.ArgsToCommandLine(Args);

    if (!WinAPI.SaferCreateLevel(WinAPI.SaferScopes.User, WinAPI.SaferLevels.NormalUser, 1, out hSaferLevel, IntPtr.Zero))
        throw new Win32Exception();

    if (!WinAPI.SaferComputeTokenFromLevel(hSaferLevel, IntPtr.Zero, out hToken, WinAPI.SaferComputeTokenFlags.None, IntPtr.Zero))
        throw new Win32Exception();

    if (!WinAPI.ConvertStringSidToSid("S-1-16-8192", out pMediumIntegritySid))
        throw new Win32Exception();
    var TIL = new TOKEN_MANDATORY_LABEL();
    TIL.Label.Attributes = 0x00000020 /* SE_GROUP_INTEGRITY */;
    TIL.Label.Sid = pMediumIntegritySid;
    pTIL = Marshal.AllocHGlobal(Marshal.SizeOf<TOKEN_MANDATORY_LABEL>());
    Marshal.StructureToPtr(TIL, pTIL, false);
    if (!WinAPI.SetTokenInformation(hToken, 25 /* TokenIntegrityLevel */, pTIL, (uint) Marshal.SizeOf<TOKEN_MANDATORY_LABEL>() + WinAPI.GetLengthSid(pMediumIntegritySid)))
        throw new Win32Exception();

    if (!WinAPI.CreateProcessAsUser(hToken, null, commandLine, ref processAttributes, ref threadAttributes, true, 0, IntPtr.Zero, null, ref si, out pi))
        throw new Win32Exception();
}
finally
{
    if (hToken != IntPtr.Zero && !WinAPI.CloseHandle(hToken))
        throw new Win32Exception();
    if (pMediumIntegritySid != IntPtr.Zero && WinAPI.LocalFree(pMediumIntegritySid) != IntPtr.Zero)
        throw new Win32Exception();
    if (pTIL != IntPtr.Zero)
        Marshal.FreeHGlobal(pTIL);
    if (pi.hProcess != IntPtr.Zero && !WinAPI.CloseHandle(pi.hProcess))
        throw new Win32Exception();
    if (pi.hThread != IntPtr.Zero && !WinAPI.CloseHandle(pi.hThread))
        throw new Win32Exception();
}

以下是除了drf的答案中列出的那些之外你需要的P / Invoke定义：

[DllImport("advapi32.dll", SetLastError = true)]
public static extern Boolean SetTokenInformation(IntPtr TokenHandle, int TokenInformationClass,
    IntPtr TokenInformation, UInt32 TokenInformationLength);

[DllImport("kernel32.dll", SetLastError = true)]
[return: MarshalAs(UnmanagedType.Bool)]
public static extern bool CloseHandle(IntPtr hObject);

[DllImport("advapi32.dll")]
public static extern uint GetLengthSid(IntPtr pSid);

[DllImport("advapi32.dll", SetLastError = true)]
public static extern bool ConvertStringSidToSid(
    string StringSid,
    out IntPtr ptrSid);

[DllImport("kernel32.dll", SetLastError = true)]
public static extern IntPtr LocalFree(IntPtr hMem);

Answer 3

最简单的解决方案是使用 explorer.exe 启动该过程。这将启动所有未启动的进程。您可以使用

启动 explorer.exe

    System.Diagnostics.Process.Start();

文件名将为“ C：\ Windows \ explorer.exe”，参数将是您要不加高引号地开始的可执行文件，并用引号引起来。

示例：

如果我想不加高度地启动 F：\ folder \ example.exe ，我会这样做：

    using System.Diagnostics;

    namespace example
    {
        class exampleClass
        {
            ProcessStartInfo exampleStartInfo = new ProcessStartInfo();
            exampleStartInfo.FileName = "C:\\Windows\\explorer.exe";
            exampleStartInfo.Arguments = "\"F:\\folder\\example.exe\"";
            Process.Start(exampleStartInfo);
        }
    }

这可能在旧版本的Windows上不起作用，但至少在我的笔记本电脑上有效，因此在Windows 10上也可以。

Answer 4

Raymond Chen在他的博客中谈到了这一点：

How can I launch an unelevated process from my elevated process and vice versa?

我在GitHub中搜索此代码的C＃版本，我在Microsoft's Visual Studio的Node.js工具存储库中找到了以下实现：SystemUtilities.cs（请参见{ {1}}函数。

以防万一文件消失了，这是文件的内容：

ExecuteProcessUnElevated

如何启动流程升级

4 个答案:

替代方法