ClientContext sharepoint to get allowed site for user

I'd like to connect to a clientcontext `

using (SP.ClientContext ctx = new ClientContext("spurl"))
        {
            try
            {
                //retrieve an other user and use this
                SP.User user = clientContext.Web.EnsureUser("me@myco.com"); 
                ctx.Load(user);
                ctx.ExecuteQuery();
            }
            catch (ServerException) { }

            //load all webs in site collection
            List<Web> allWebs = new List<Web>();
            LoadAllWebs(ctx.Site.RootWeb, allWebs);
            //print 
            foreach (SP.Web web in allWebs)
            {
                ctx.Load(web.CurrentUser);
                ctx.ExecuteQuery();
                string login = web.CurrentUser.LoginName;

                dr = dt.NewRow();
                dr["siteTitle"] = login;
                dr["siteurl"] = web.Url;
                dt.Rows.Add(dr);
            }
        }

My need is get allowed site for specific user but my script run with a people who is site collection administrator.

Are there a way to get allowed site for specific user? Are there a way to connect the clientcontext for a specific user?