impersonation - Impersonate admin account to edit registry key not working (C#)

Question

I am using the following code to edit a registry key in the local machine hive ('SOFTWAREMicrosoftWindows NTCurrentVersionProfileList\%SID%'). Everything seems to be fine until I actually try to open the registry key (with write permissions); a SecurityException is thrown with the message 'Requested registry access is not allowed.' I've checked and rechecked the permissions for the registry key and the user I'm impersonating and it all checks out. The code runs fine when logged into the impersonated user's account, but when logged in as a restricted user, it fails. It's as if the impersonation works all except for giving the thread administrative privileges. Any ideas about how to fix this would be greatly appreciated!

string KEY_STR = "SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList" + WindowsIdentity.GetCurrent().User.Value;
WindowsImpersonationContext adminContext = null;
IntPtr tokenHandle = new IntPtr(0);
try
{
    LogonUser(userName, domainName, password, LOGON32_LOGON_INTERACTIVE, LOGON32_PROVIDER_DEFAULT, ref tokenHandle);
    if (tokenHandle.Equals(new IntPtr(0))) LogonUser(userName, computerName, password, LOGON32_LOGON_INTERACTIVE, LOGON32_PROVIDER_DEFAULT, ref tokenHandle);
    WindowsIdentity adminIdentity = new WindowsIdentity(tokenHandle);
    adminContext = adminIdentity.Impersonate();
    RegistryKey key = Registry.LocalMachine.OpenSubKey(KEY_STR, true);
    key.SetValue("State", 0x60001);
    Console.Out.WriteLine("User profile changed to Mandatory.");
}
catch (Exception ex)
{
    Console.Out.WriteLine("
Unable to set profile to Mandatory:
" + ex.Message);
}
finally
{
    adminContext.Undo();
    if (tokenHandle != IntPtr.Zero) CloseHandle(tokenHandle);
}

Answer 1

I know this thread is pretty old, and maybe you solved this already, but I did it like this with no issues on a Win7 box:

string userName = "domain\user"; // there's really just one slash, 
//but you have to escape it if hard-coding.. 
//if brought in by a text box, it would be just domainuser

string password = "whatever";
string KEY_STR = "SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList" + WindowsIdentity.GetCurrent().User.Value;

WindowsImpersonationContext adminContext = Impersonation.getWic(userName, password);
if (adminContext != null)
{
    try
    {
       RegistryKey key = Registry.LocalMachine.OpenSubKey(KEY_STR, true);

       //NOTE: If this was on a remote machine, that line would just be:
       // RegistryKey key = RegistryKey.OpenRemoteSubKey(RegistryHive.LocalMachine, computerName).OpenSubKey(KEY_STR, true);

       key.SetValue("State", 0x60001);
       Console.Out.WriteLine("User profile changed to Mandatory.");
    }
    catch (Exception ex)
    {
        Console.Out.WriteLine("
Unable to set profile to Mandatory:
" + ex.Message);
        Impersonation.endImpersonation();
        adminContext.Undo();
    }
    finally
    {
        Impersonation.endImpersonation();
        // The above line does what you had, here --            
        //if (tokenHandle != IntPtr.Zero) CloseHandle(tokenHandle);
        adminContext.Undo();
    }
}

This is my separate Impersonation class. It has 2 main entry points, getWic() and doImpersonation() -- getWic() will take a username that looks like domainuser or machinenameuser and split them up into their component parts before handing it off to doImpersonation(), while doImpersonation() accepts the parts already split, if you have it like that and don't need the code in getWic(). Both return a WindowsImpersonationContext.

using System;
using System.Data;
using System.Configuration;
using System.Security.Permissions;
using System.Security.Principal;
using System.Runtime.InteropServices;

[assembly: SecurityPermissionAttribute(SecurityAction.RequestMinimum, UnmanagedCode = true)]
[assembly: PermissionSetAttribute(SecurityAction.RequestMinimum, Name = "FullTrust")]
public class Impersonation
{
    [DllImport("advapi32.dll", EntryPoint = "LogonUser")]
    public static extern bool LogonUser(
        string lpszUsername,
        string lpszDomain,
        string lpszPassword,
        int dwLogonType,
        int dwLogonProvider,
        ref IntPtr phToken);

    [DllImport("advapi32.dll", CharSet = CharSet.Auto, SetLastError = true)]
    public extern static bool DuplicateToken(IntPtr ExistingTokenHandle,
        int SECURITY_IMPERSONATION_LEVEL, ref IntPtr DuplicateTokenHandle);

    [DllImport("kernel32.dll", CharSet = CharSet.Auto)]
    public extern static bool CloseHandle(IntPtr handle);

    // Declare the Logon Types as constants
    const int LOGON32_LOGON_INTERACTIVE = 2;
    const int LOGON32_LOGON_NETWORK = 3;
    const int LOGON32_LOGON_BATCH = 4;
    const int LOGON32_LOGON_SERVICE = 5;
    const int LOGON32_LOGON_UNLOCK = 7;
    const int LOGON32_LOGON_NETWORK_CLEARTEXT = 8; // Win2K or higher   
    const int LOGON32_LOGON_NEW_CREDENTIALS = 9; // Win2K or higher

    // Declare the Logon Providers as constants
    const int LOGON32_PROVIDER_DEFAULT = 0;
    const int LOGON32_PROVIDER_WINNT50 = 3;
    const int LOGON32_PROVIDER_WINNT40 = 2;
    const int LOGON32_PROVIDER_WINNT35 = 1;

    // Declare the Impersonation Levels as constants
    const int SecurityAnonymous = 0;
    const int SecurityIdentification = 1;
    const int SecurityImpersonation = 2;
    const int SecurityDelegation = 3;

    private static WindowsIdentity newId;
    private static IntPtr tokenHandle = new IntPtr(0);
    private static IntPtr dupeTokenHandle = new IntPtr(0);

    [PermissionSetAttribute(SecurityAction.Demand, Name = "FullTrust")]
    public static WindowsImpersonationContext doImpersonation(string svcUserName, string domainName, string password)
    {
        // Initialize tokens
        tokenHandle = IntPtr.Zero;
        dupeTokenHandle = IntPtr.Zero;

        // Call LogonUser to obtain a handle to an access token
        bool returnValue = LogonUser(svcUserName, domainName, password,
        LOGON32_LOGON_INTERACTIVE, LOGON32_PROVIDER_WINNT50, ref tokenHandle);

        if (returnValue == false)
        {
            int ret = Marshal.GetLastWin32Error();

            //Check for errors
            if (ret != NO_ERROR)
                throw new Exception("LogonUser failed with error code : " + GetError(ret));
        }

        bool retVal = DuplicateToken(tokenHandle, SecurityImpersonation, ref dupeTokenHandle);
        if (retVal == false)
        {
            CloseHandle(tokenHandle);
            throw new Exception("Exception thrown in trying to duplicate token.");
        }
        else
        {
            // Begin Impersonation
            bool bRetVal = DuplicateToken(tokenHandle,
            (int)SecurityImpersonation, ref dupeTokenHandle);

            newId = new WindowsIdentity(dupeTokenHandle);
            WindowsImpersonationContext impersonatedUser = newId.Impersonate();
            return impersonatedUser;
        }
    }

    public static void endImpersonation()
    {
        if (dupeTokenHandle != IntPtr.Zero)
            CloseHandle(dupeTokenHandle);
        if (tokenHandle != IntPtr.Zero)
            CloseHandle(tokenHandle);
    }

    public static WindowsImpersonationContext getWic(string userNameStringFromTextbox, string password)
    {
        try
        {
            // Establish impersonation
            string svcUser = userNameStringFromTextbox;
            string[] arrUser = new string[2];
            arrUser = svcUser.Split('\');
            string domain = arrUser[0];
            string svcUserName = arrUser[1];

            // Get Password:  Convert from Base-64 String to decrypted string            
            //string keyLength = ConfigurationManager.AppSettings["keyLength"].ToString();
            //string keyLocation = ConfigurationManager.AppSettings["keyLocation"].ToString();
            //password = RSAEncrypt.DecryptData(password, keyLength, keyLocation);

            WindowsImpersonationContext wic = doImpersonation(svcUserName, domain, password);
            return wic;
        }
        catch (Exception ex)
        {
            ErrorLog.ErrorRoutine(new Exception("getWic() Error: " + ex.ToString()), ErrorMessage.NOTIFY_APP_ERROR);
            return null;
        }
    }

    #region Errors
    const int NO_ERROR = 0;

    const int ERROR_ACCESS_DENIED = 5;
    const int ERROR_ALREADY_ASSIGNED = 85;
    const int ERROR_BAD_DEVICE = 1200;
    const int ERROR_BAD_NET_NAME = 67;
    const int ERROR_BAD_PROVIDER = 1204;
    const int ERROR_CANCELLED = 1223;
    const int ERROR_EXTENDED_ERROR = 1208;
    const int ERROR_INVALID_ADDRESS = 487;
    const int ERROR_INVALID_PARAMETER = 87;
    const int ERROR_INVALID_PASSWORD = 1216;
    const int ERROR_MORE_DATA = 234;
    const int ERROR_NO_MORE_ITEMS = 259;
    const int ERROR_NO_NET_OR_BAD_PATH = 1203;
    const int ERROR_NO_NETWORK = 1222;
    const int ERROR_SESSION_CREDENTIAL_CONFLICT = 1219;

    const int ERROR_BAD_PROFILE = 1206;
    const int ERROR_CANNOT_OPEN_PROFILE = 1205;
    const int ERROR_DEVICE_IN_USE = 2404;
    const int ERROR_NOT_CONNECTED = 2250;
    const int ERROR_OPEN_FILES = 2401;

    private struct ErrorClass
    {
        public int num;
        public string message;
        public ErrorClass(int num, string message)
        {
            this.num = num;
            this.message = message;
         }
    }

    private static ErrorClass[] ERROR_LIST = new ErrorClass[] {
        new ErrorClass(ERROR_ACCESS_DENIED, "Error: Access Denied"),
        new ErrorClass(ERROR_ALREADY_ASSIGNED, "Error: Already Assigned"),
        new ErrorClass(ERROR_BAD_DEVICE, "Error: Bad Device"),
        new ErrorClass(ERROR_BAD_NET_NAME, "Error: Bad Net Name"),
        new ErrorClass(ERROR_BAD_PROVIDER, "Error: Bad Provider"),
        new ErrorClass(ERROR_CANCELLED, "Error: Cancelled"),
        new ErrorClass(ERROR_EXTENDED_ERROR, "Error: Extended Error"),
        new ErrorClass(ERROR_INVALID_ADDRESS, "Error: Invalid Address"),
        new ErrorClass(ERROR_INVALID_PARAMETER, "Error: Invalid Parameter"),
        new ErrorClass(ERROR_INVALID_PASSWORD, "Error: Invalid Password"),
        new ErrorClass(ERROR_MORE_DATA, "Error: More Data"),
        new ErrorClass(ERROR_NO_MORE_ITEMS, "Error: No More Items"),
        new ErrorClass(ERROR_NO_NET_OR_BAD_PATH, "Error: No Net Or Bad Path"),
        new ErrorClass(ERROR_NO_NETWORK, "Error: No Network"),
        new ErrorClass(ERROR_SESSION_CREDENTIAL_CONFLICT, "Error: Credential Conflict"),
        new ErrorClass(ERROR_BAD_PROFILE, "Error: Bad Profile"),
        new ErrorClass(ERROR_CANNOT_OPEN_PROFILE, "Error: Cannot Open Profile"),
        new ErrorClass(ERROR_DEVICE_IN_USE, "Error: Device In Use"),
        new ErrorClass(ERROR_NOT_CONNECTED, "Error: Not Connected"),
        new ErrorClass(ERROR_OPEN_FILES, "Error: Open Files"),
    };

    private static string GetError(int errNum)
    {
        foreach (ErrorClass er in ERROR_LIST)
        {
            if (er.num == errNum) return er.message;
        }
        return "Error: Unknown, " + errNum;
    }
    #endregion
}