Untitled

<?PHP
/* Turn error reporting for securility purposes */
error_reporting(0);

/* Starts the session */
session_start();

/*Checks if session exist or not.*/
if ($_SESSION['username']!=NULL and $_SESSION['password']!=NULL)
{
    /*if it doesn't exist then go to the user's page*/
    echo "<script>window.location='user.php';</script>";
    exit;
}

/*if data was submited*/
if ($_REQUEST['submit'] == 'submit')
{
    /* Get data from web form */
    $username = $_REQUEST['username'];
    $password = $_REQUEST['password'];

    /*create the key out of the username password (concept) */
    $key = $username[0] . $username[1] . $username[2] . $password[3] . $password[2];

    /* encypts password */
    $cppassword = crypt($password,$key);

    $dbuser="Guest";
    $dbpass="guest";
    $dbname="bktc";

    /*
      Connects to the database using guest login
      Guest login can only use the select function
    */
    $chandle = mysql_connect("localhost", $dbuser, $dbpass) or die("Connection Failure to Database");
    mysql_select_db($dbname,$chandle) or die($dbname . " not found." . $dbuser);

    /* Get the user from the database */
    $sqlcomm = "SELECT * FROM 'users'";
    $results = mysql_query($sqlcomm) or die(mysql_error());

    while($row = mysql_fetch_array($rersult)
    {
        /*Check if the user info match the database or not*/
        if ($row['USERNAME'] == $username) and ($row['PASSWORD'] == $cpassword))
        {
            /* Create a session for the user */
            session_cache_limiter('private');
            $cache_limiter = session_cache_limiter();
            /*set expiration, username and password into the session */
            $session_expire = session_cache_expire();
            $_SESSION['username']=$username;
            $_SESSION['password']=$cpassword;
            $_SESSION['group'] = $row['GROUP'];
            /* redirect you to the user page */
            echo "<script>window.location='user.php';</script>";
            exit;
        }
    }

    /* Give them an error */
    echo "Username or password is invaild.<br><br>";

}
?>

<html>
<form name="loginform" method="post" action="login.php">
Username: <input type=text name="username"><br>
Password: <input type="password" name="password"><br>
<input type="submit" value="Login">
<input type="hidden" value="submit" name="submit">
</form>
</html>