System.Security.Principal.WindowsIdentity file.copy   

I have follwing code it works only from the same system but not from the 
other client or system.

 Dim aa As New AliasAccount("Domain\UserName", "Password)
                    aa.BeginImpersonation()

                    Dim thePath As String  'source path
                    Dim destPath As String 'destination path other system

                    File.Copy(thePath, destPath, 1)

                    aa.EndImpersonation()


Public Class AliasAccount
    Private _username, _password, _domainname As String

        Private _tokenHandle As New IntPtr(0)
        Private _dupeTokenHandle As New IntPtr(0)
        Private _impersonatedUser As 
System.Security.Principal.WindowsImpersonationContext


        Public Sub New(ByVal username As String, ByVal password As String)
            Dim nameparts() As String = username.Split("\")
            If nameparts.Length > 1 Then
                _domainname = nameparts(0)
                _username = nameparts(1)
            Else
                _username = username
            End If
            _password = password
        End Sub

        Public Sub New(ByVal username As String, ByVal password As String, 
ByVal domainname As String)
            _username = username
            _password = password
            _domainname = domainname
        End Sub


        Public Sub BeginImpersonation()
            Const LOGON32_PROVIDER_DEFAULT As Integer = 0
            Const LOGON32_LOGON_INTERACTIVE As Integer = 2
            Const SecurityImpersonation As Integer = 2

            Dim win32ErrorNumber As Integer

            _tokenHandle = IntPtr.Zero
            _dupeTokenHandle = IntPtr.Zero

            If Not LogonUser(_username, _domainname, _password, 
LOGON32_LOGON_INTERACTIVE, LOGON32_PROVIDER_DEFAULT, _tokenHandle) Then
                win32ErrorNumber = 
System.Runtime.InteropServices.Marshal.GetLastWin32Error()
                Throw New ImpersonationException(win32ErrorNumber, 
GetErrorMessage(win32ErrorNumber), _username, _domainname)
            End If

            If Not DuplicateToken(_tokenHandle, SecurityImpersonation, 
_dupeTokenHandle) Then
                win32ErrorNumber = 
System.Runtime.InteropServices.Marshal.GetLastWin32Error()

                CloseHandle(_tokenHandle)
                Throw New ImpersonationException(win32ErrorNumber, "Unable 
to duplicate token!", _username, _domainname)
            End If

            Dim newId As New 
System.Security.Principal.WindowsIdentity(_dupeTokenHandle)
            _impersonatedUser = newId.Impersonate()
        End Sub


        Public Sub EndImpersonation()
            If Not _impersonatedUser Is Nothing Then
                _impersonatedUser.Undo()
                _impersonatedUser = Nothing

                If Not System.IntPtr.op_Equality(_tokenHandle, IntPtr.Zero) 
Then
                    CloseHandle(_tokenHandle)
                End If
                If Not System.IntPtr.op_Equality(_dupeTokenHandle, 
IntPtr.Zero) Then
                    CloseHandle(_dupeTokenHandle)
                End If
            End If
        End Sub


        Public ReadOnly Property username() As String
            Get
                Return _username
            End Get
        End Property

        Public ReadOnly Property domainname() As String
            Get
                Return _domainname
            End Get
        End Property


        Public ReadOnly Property currentWindowsUsername() As String
            Get
                Return 
System.Security.Principal.WindowsIdentity.GetCurrent().Name
            End Get
        End Property


#Region "Exception Class"
        Public Class ImpersonationException
            Inherits System.Exception

            Public ReadOnly win32ErrorNumber As Integer

            Public Sub New(ByVal win32ErrorNumber As Integer, ByVal msg As 
String, ByVal username As String, ByVal domainname As String)
                MyBase.New(String.Format("Impersonation of {1}\{0} failed! 
[{2}] {3}", username, domainname, win32ErrorNumber, msg))
                Me.win32ErrorNumber = win32ErrorNumber
            End Sub
        End Class
#End Region


#Region "External Declarations and Helpers"
        Private Declare Auto Function LogonUser Lib "advapi32.dll" (ByVal 
lpszUsername As [String], _
                ByVal lpszDomain As [String], ByVal lpszPassword As 
[String], _
                ByVal dwLogonType As Integer, ByVal dwLogonProvider As 
Integer, _
                ByRef phToken As IntPtr) As Boolean


        Private Declare Auto Function DuplicateToken Lib "advapi32.dll" 
(ByVal ExistingTokenHandle As IntPtr, _
                    ByVal SECURITY_IMPERSONATION_LEVEL As Integer, _
                    ByRef DuplicateTokenHandle As IntPtr) As Boolean


        Private Declare Auto Function CloseHandle Lib "kernel32.dll" (ByVal 
handle As IntPtr) As Boolean


        <System.Runtime.InteropServices.DllImport("kernel32.dll")> _
        Private Shared Function FormatMessage(ByVal dwFlags As Integer, 
ByRef lpSource As IntPtr, _
                ByVal dwMessageId As Integer, ByVal dwLanguageId As Integer, 
ByRef lpBuffer As [String], _
                ByVal nSize As Integer, ByRef Arguments As IntPtr) As Integer
        End Function


        Private Function GetErrorMessage(ByVal errorCode As Integer) As String
            Dim FORMAT_MESSAGE_ALLOCATE_BUFFER As Integer = &H100
            Dim FORMAT_MESSAGE_IGNORE_INSERTS As Integer = &H200
            Dim FORMAT_MESSAGE_FROM_SYSTEM As Integer = &H1000

            Dim messageSize As Integer = 255
            Dim lpMsgBuf As String
            Dim dwFlags As Integer = FORMAT_MESSAGE_ALLOCATE_BUFFER Or 
FORMAT_MESSAGE_FROM_SYSTEM Or FORMAT_MESSAGE_IGNORE_INSERTS

            Dim ptrlpSource As IntPtr = IntPtr.Zero
            Dim prtArguments As IntPtr = IntPtr.Zero

            Dim retVal As Integer = FormatMessage(dwFlags, ptrlpSource, 
errorCode, 0, lpMsgBuf, messageSize, prtArguments)
            If 0 = retVal Then
                Throw New System.Exception("Failed to format message for 
error code " + errorCode.ToString() + ". ")
            End If

            Return lpMsgBuf
        End Function

#End Region

    
End Class

date: Fri, 8 Feb 2008 08:20:00 -0800   author:   vinod