Sitefinity ASP.NET CMS - Content Management System

using System;
using Telerik.Security.ActiveDirectory;
using System.Collections.Generic;
using System.Text;
using System.Web;
using System.DirectoryServices;

public class CustomRoleProvider : TelerikADRoleProvider
{
    public override string[] GetRolesForUser(string userName)
    {
        DirectoryEntry searchRoot = new DirectoryEntry(this.ADConnectionString, this.ADUserName, this.ADPassword, this.AuthType);
        DirectorySearcher userSearcher = new DirectorySearcher(searchRoot, String.Format(this.UserSearchFilter, userName));
        List<string> groupsList = new List<string>();

        DirectoryEntry userEntry = null;
        try
        {
            SearchResult userResult = userSearcher.FindOne();
            userEntry = userResult.GetDirectoryEntry();
        }
        catch (System.Runtime.InteropServices.COMException)
        {
            // problem occured with the LDAP query, manage the expection if you like
            throw;
        }

        if (userEntry != null)
        {
            StringBuilder groupsFilter = new StringBuilder();

            groupsFilter.Append("(|");
            userEntry.RefreshCache(new string[] { "tokenGroups" });

            foreach (byte[] sid in userEntry.Properties["tokenGroups"])
            {
                groupsFilter.AppendFormat("(objectSid={0})", BuildFilterOctetString(sid));
            }
            groupsFilter.Append(")");

            List<string> result = new List<string>();
            using (searchRoot)
            {
                DirectorySearcher groupsSearcher = new DirectorySearcher(searchRoot, groupsFilter.ToString());
                try
                {
                    SearchResultCollection groupsCollection = groupsSearcher.FindAll();

                    foreach (SearchResult sr in groupsCollection)
                    {
                        result.Add(sr.Properties["samAccountName"][0].ToString());
                    }
                }
                catch (System.Runtime.InteropServices.COMException)
                {
                    // problem occured with the LDAP query, manage the expection if you like
                    throw;
                }
            }

            return result.ToArray();
        }
        else
            return new string[0];
    }

    private string BuildFilterOctetString(byte[] bytes)
    {
        StringBuilder result = new StringBuilder();

        for (int i = 0; i < bytes.Length; i++)
        {
            result.AppendFormat(
                "\\{0}",
                bytes[i].ToString("X2")
                );
        }
        return result.ToString();
    }
}