impersonate a user
12144 ワード
// This sample demonstrates the use of the WindowsIdentity class to impersonate a user.
// IMPORTANT NOTES:
// This sample requests the user to enter a password on the console screen.
// Because the console window does not support methods allowing the password to be masked,
// it will be visible to anyone viewing the screen.
// On Windows Vista and later this sample must be run as an administrator.
using System;
using System.Runtime.InteropServices;
using System.Security.Principal;
using System.Security.Permissions;
using Microsoft.Win32.SafeHandles;
using System.Runtime.ConstrainedExecution;
using System.Security;
public class ImpersonationDemo
{
[DllImport("advapi32.dll", SetLastError = true, CharSet = CharSet.Unicode)]
public static extern bool LogonUser(String lpszUsername, String lpszDomain, String lpszPassword,
int dwLogonType, int dwLogonProvider, out SafeTokenHandle phToken);
[DllImport("kernel32.dll", CharSet = CharSet.Auto)]
public extern static bool CloseHandle(IntPtr handle);
// Test harness.
// If you incorporate this code into a DLL, be sure to demand FullTrust.
[PermissionSetAttribute(SecurityAction.Demand, Name = "FullTrust")]
public static void Main(string[] args)
{
SafeTokenHandle safeTokenHandle;
try
{
string userName, domainName;
// Get the user token for the specified user, domain, and password using the
// unmanaged LogonUser method.
// The local machine name can be used for the domain name to impersonate a user on this machine.
Console.Write("Enter the name of the domain on which to log on: ");
domainName = Console.ReadLine();
Console.Write("Enter the login of a user on {0} that you wish to impersonate: ", domainName);
userName = Console.ReadLine();
Console.Write("Enter the password for {0}: ", userName);
const int LOGON32_PROVIDER_DEFAULT = 0;
//This parameter causes LogonUser to create a primary token.
const int LOGON32_LOGON_INTERACTIVE = 2;
// Call LogonUser to obtain a handle to an access token.
bool returnValue = LogonUser(userName, domainName, Console.ReadLine(),
LOGON32_LOGON_INTERACTIVE, LOGON32_PROVIDER_DEFAULT,
out safeTokenHandle);
Console.WriteLine("LogonUser called.");
if (false == returnValue)
{
int ret = Marshal.GetLastWin32Error();
Console.WriteLine("LogonUser failed with error code : {0}", ret);
throw new System.ComponentModel.Win32Exception(ret);
}
using (safeTokenHandle)
{
Console.WriteLine("Did LogonUser Succeed? " + (returnValue ? "Yes" : "No"));
Console.WriteLine("Value of Windows NT token: " + safeTokenHandle);
// Check the identity.
Console.WriteLine("Before impersonation: "
+ WindowsIdentity.GetCurrent().Name);
// Use the token handle returned by LogonUser.
using (WindowsIdentity newId = new WindowsIdentity(safeTokenHandle.DangerousGetHandle()))
{
using (WindowsImpersonationContext impersonatedUser = newId.Impersonate())
{
// Check the identity.
Console.WriteLine("After impersonation: "
+ WindowsIdentity.GetCurrent().Name);
}
}
// Releasing the context object stops the impersonation
// Check the identity.
Console.WriteLine("After closing the context: " + WindowsIdentity.GetCurrent().Name);
}
}
catch (Exception ex)
{
Console.WriteLine("Exception occurred. " + ex.Message);
}
finally
{
Console.ReadKey();
}
}
}
public sealed class SafeTokenHandle : SafeHandleZeroOrMinusOneIsInvalid
{
private SafeTokenHandle()
: base(true)
{
}
[DllImport("kernel32.dll")]
[ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)]
[SuppressUnmanagedCodeSecurity]
[return: MarshalAs(UnmanagedType.Bool)]
private static extern bool CloseHandle(IntPtr handle);
protected override bool ReleaseHandle()
{
return CloseHandle(handle);
}
}