Impersonation not working in ASP.NET

[suhail242]

I am trying to get response back using impersonated user

I am loggedon as user "xyz" on domain "DEV", I created an empty website which at session start in global.asax writes current user(System.Security.Principal.WindowsIdentity.Get Current()) in a file.

I am calling default.aspx from Nunit(using asp extensions) using system.net.webrequest as follows

    ImpersonateLogonUser.ClsImpersonateUser impersonate = new ImpersonateLogonUser.ClsImpersonateUser();
    impersonate.ImpersonateUser("TestUser1", "DEV", "");
    System.Net.WebRequest request = System.Net.WebRequest.Create("http://localhost:4445/Default.aspx");
    request.GetResponse();
 

I am expecting System.Security.Principal.WindowsIdentity.GetCurre nt() to write TestUser1 in file but it is writing "xyz"


I have tested impersonation is working if I call the code from within SessinStart in global.asax


Impersonation code is as follows

    using System;
    using System.Collections;
    using System.ComponentModel;
    using System.Data;
    using System.Runtime.InteropServices;  // DllImport
    using System.Security.Principal; // WindowsImpersonationContext
    using System.Security.Permissions; // PermissionSetAttribute
 
    namespace ImpersonateLogonUser
    {
        public enum SECURITY_IMPERSONATION_LEVEL : int
        {
            SecurityAnonymous = 0,
            SecurityIdentification = 1,
            SecurityImpersonation = 2,
            SecurityDelegation = 3
        }
        public class ClsImpersonateUser
        {    
 
            // obtains user token
            [DllImport("advapi32.dll", SetLastError = true)]
            public static extern bool LogonUser(string pszUsername, string pszDomain, string pszPassword,
                int dwLogonType, int dwLogonProvider, ref IntPtr phToken);
 
            // closes open handes returned by LogonUser
            [DllImport("kernel32.dll", CharSet = CharSet.Auto)]
            public extern static bool CloseHandle(IntPtr handle);
 
            // creates duplicate token handle
            [DllImport("advapi32.dll", CharSet = CharSet.Auto, SetLastError = true)]
            public extern static bool DuplicateToken(IntPtr ExistingTokenHandle,
                int SECURITY_IMPERSONATION_LEVEL, ref IntPtr DuplicateTokenHandle);
 
 
            private System.Security.Principal.WindowsImpersonationContext newUser;
 
            /// <summary>
            /// Required designer variable.
            /// </summary>
            private System.ComponentModel.Container components = null;
 
 
            /// <summary>
            /// Attempts to impersonate a user.  If successful, returns
            /// a WindowsImpersonationContext of the new users identity.
            /// </summary>
            /// <param name="sUsername">Username you want to impersonate</param>
            /// <param name="sDomain">Logon domain</param>
            /// <param name="sPassword">User's password to logon with</param></param>
            /// <returns></returns>
            public WindowsImpersonationContext ImpersonateUser(string sUsername, string sDomain, string sPassword)
            {
                // initialize tokens
                IntPtr pExistingTokenHandle = new IntPtr(0);
                IntPtr pDuplicateTokenHandle = new IntPtr(0);
                pExistingTokenHandle = IntPtr.Zero;
                pDuplicateTokenHandle = IntPtr.Zero;
 
                // if domain name was blank, assume local machine
                if (sDomain == "")
                    sDomain = System.Environment.MachineName;
 
                try
                {
                    string sResult = null;
 
                    const int LOGON32_PROVIDER_DEFAULT = 0;
 
                    // create token
                    const int LOGON32_LOGON_INTERACTIVE = 2;
                    //const int SecurityImpersonation = 2;
 
                    // get handle to token
                    bool bImpersonated = LogonUser(sUsername, sDomain, sPassword,
                        LOGON32_LOGON_INTERACTIVE, LOGON32_PROVIDER_DEFAULT, ref pExistingTokenHandle);
 
                    // did impersonation fail?
                    if (false == bImpersonated)
                    {
                        int nErrorCode = Marshal.GetLastWin32Error();
                        sResult = "LogonUser() failed with error code: " + nErrorCode + "\r\n";
 
                        // show the reason why LogonUser failed
                        //MessageBox.Show(this, sResult, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
                    }
 
                    // Get identity before impersonation
                    sResult += "Before impersonation: " + WindowsIdentity.GetCurrent().Name + "\r\n";
 
                    bool bRetVal = DuplicateToken(pExistingTokenHandle, (int)SECURITY_IMPERSONATION_LEVEL.SecurityImpersonation, ref pDuplicateTokenHandle);
 
                    // did DuplicateToken fail?
                    if (false == bRetVal)
                    {
                        int nErrorCode = Marshal.GetLastWin32Error();
                        CloseHandle(pExistingTokenHandle); // close existing handle
                        sResult += "DuplicateToken() failed with error code: " + nErrorCode + "\r\n";
 
                        // show the reason why DuplicateToken failed
                        //MessageBox.Show(this, sResult, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
                        return null;
                    }
                    else
                    {
                        // create new identity using new primary token
                        WindowsIdentity newId = new WindowsIdentity(pDuplicateTokenHandle);
                        WindowsImpersonationContext impersonatedUser = newId.Impersonate();
 
                        // check the identity after impersonation
                        sResult += "After impersonation: " + WindowsIdentity.GetCurrent().Name + "\r\n";
 
                        //MessageBox.Show(this, sResult, "Success", MessageBoxButtons.OK, MessageBoxIcon.Information);
                        return impersonatedUser;
                    }
                }
                catch (Exception ex)
                {
                    throw ex;
                }
                finally
                {
                    // close handle(s)
                    if (pExistingTokenHandle != IntPtr.Zero)
                        CloseHandle(pExistingTokenHandle);
                    if (pDuplicateTokenHandle != IntPtr.Zero)
                        CloseHandle(pDuplicateTokenHandle);
                }
            }
        }
    }