Question

I am working on service application that needs to monitor windows session changes and automatically start an application if a specific user logged on to.

Here is how it works, I have a file with a list of Windows usernames stored in a user principal name format ([e-mail]). My service will monitor any session changes and will take certain actions once one of those users gets logged on.

List<string> _UsersList;
 object _sessionCheckLock = new object();
        void OnCheckSession(int nSessionId, bool bIsLoggIn)
        {
            lock(_sessionCheckLock)
            {
                try
                {
                    string sUserName = string.Empty;
                    string sDomain = string.Empty;

                    IntPtr pUserName = IntPtr.Zero;
                    uint nBytesReturned = 0;
                    if (WTSQuerySessionInformation(IntPtr.Zero, (uint)nSessionId, WTS_INFO_CLASS.WTSUserName, out pUserName, out nBytesReturned) && (pUserName != IntPtr.Zero))
                    {
                        sUserName = Marshal.PtrToStringAnsi(pUserName);

                        WTSFreeMemory(pUserName);

                        IntPtr pDomain = IntPtr.Zero;
                        if(WTSQuerySessionInformation(IntPtr.Zero, (uint)nSessionId, WTS_INFO_CLASS.WTSDomainName, out pDomain, out nBytesReturned) && (pDomain != IntPtr.Zero))
                        {
                            sDomain = Marshal.PtrToStringAnsi(pDomain);
                            WTSFreeMemory(pDomain);
                        }
                        else
                        {

                        }

                        if (!string.IsNullOrEmpty(sUserName))
                        {
                          if(!string.IsNullOrEmpty(sDomain)
                          {
                              sUserName += "@" + sDomain;
                          }

                            foreach(string username in _UsersList)
                            {
                               if(string.Compare(sUsername, username, true)==0)
                               {
                                //Do a couple of things
                                return;
                               }
                            }

                        }
                    }
                    else
                    {
                        return;
                    }
                }
                catch (System.Exception ex)
                {

                }
            }
        }

The above code is the function I call whenever a new logon event is raised. The _UsersList is a list of strings that contains all the usernames that the service is allowed to work with.
The problem here is that WTSQuerySessionInformation when used with WTS_INFO_CLASS.WTSDomainName does not return the full name of the domain and therefore the comparison fails.For example if a username called ([e-mail]) exists in the list of user and logs on, when querying for the domain name of the session, it returns only (DOMAIN) without the .LOCAL appendix. I need to find a way to get the full domain name to match the one in my list.

Can someone help please

Answer 1

Look into Cassia.Net, this is a very useful.

You can download the source code, i used this for a project where i had to get all the users that were logged on to a server.

cassia
.NET Windows Terminal Services / Remote Desktop Services Library

http://code.google.com/p/cassia/

hope that helps