Recently I was working on one of main projects that amongst other things retrieves some user properties from Active Directory.
In order to use Exchange 2007 Webservices I needed to retrieve the SID because the SID was needed when impersonating a given user. This articke describes how to retrieve the SID into a byte array and using P/Invoke.
Step 1 – Search the AD
1 public SearchResultCollection getUserInfo(string ldapPath)
2 {
3 string ADUserName = ConfigurationManager.AppSettings[“UserName”];
4 string ADPassword = ConfigurationManager.AppSettings[“Password”];
5 DirectoryEntry rootEntry = new DirectoryEntry(ldapPath, ADUserName, ADPassword);
6 DirectorySearcher searcher = new DirectorySearcher(rootEntry);
7 //add the properties to retrieve
8 //accountstatus
9 searcher.PropertiesToLoad.Add(“userAccountControl”);
10 //mail
11 searcher.PropertiesToLoad.Add(“mail”);
12 searcher.PropertiesToLoad.Add(“accountExpires”);
13 searcher.PropertiesToLoad.Add(“proxyaddresses”);
14 searcher.PropertiesToLoad.Add(“SAMAccountName”);
15 searcher.PropertiesToLoad.Add(“objectSid”);
16 SearchResultCollection results;
17 results = searcher.FindAll();
18 return results;
19 }
Step 2 – loop the SearchResultCollection retriveing the “objectSid”
string sidStringValue=””;
foreach (SearchResult result in src)
{
//reset SID
byte[] SID = null;
if (result.Properties[“objectSid”].Count > 0)
{
SID = (byte[]) result.Properties[“objectSid”][0];
}
sidStringValue = GetSidString(SID);
}//end foreach
Step 3 – In the code example above a call to the method “GetSidString” is made – this method looks like this:
[DllImport(“advapi32”, CharSet = CharSet.Auto, SetLastError = true)]
static extern bool ConvertSidToStringSid([MarshalAs(UnmanagedType.LPArray)] byte[] pSID, out IntPtr ptrSid);
public static string GetSidString(byte[] sid)
{
IntPtr ptrSid;
string sidString;
if (!ConvertSidToStringSid(sid, out ptrSid))
throw new System.ComponentModel.Win32Exception();
try
{
sidString = Marshal.PtrToStringAuto(ptrSid);
}
finally
{
Marshal.FreeHGlobal(ptrSid);
}
return sidString;
}
}
