Suche Login Script

<?php


   session_start();

   $validUser = (isset($_SESSION['validUser'])) ? true : false;

   if (isset($_POST['user']))
   {
       mysql_connect("host", "user", "passwort") or
          die ("Connection failed");

       mysql_select_db("Datenbankname") or
          die ("DB doesn't exists");

       $query = "Select
                   count(*)
                 from
                   tabelle
                 where
                   user='" . mysql_real_escape_string($_POST['user']) . "'
                  and
                   passwort='" . md5($_POST['passwort']) . "'";

        $result = mysql_query($query) or
                    die ("MySQL-Error: " . mysql_error());

        $count = mysql_result($result, 0);

        if ($count != 0)
        {
            $validUser = true;
            $_SESSION['validUser'] = true;
        }
        else
          $validUser = false;
   }

   if ($validUser == false)
   {
      echo "<form action='" . $_SERVER['SCRIPT_NAME'] . "' method='post'>
            User: <input type='text' name='user'>


            Paswort: <input type='password' name='passwort'>
            </form>\n";
   }
   else
   {
      echo "Ich bin ein eingeloggter User";
   }
?>