Model or Library

[eluser]drale2k[/eluser]
Hi, i wrote a Login Class but i am not sure if it is better for a Model or a Library. In this case it is a Model, should it be ?

Code:

class Login_Model extends Model
{
    function Login_Model()
    {
        parent::Model();
    }
    
    function verifyUser($u, $pw, $bool_escape_str = TRUE)
    {
        $this->db->select('id, username, email, last_login');

        // check if escape or not
        
        if ($bool_escape_str == FALSE)
        {
            $this->db->where('username', $u);
            $this->db->where('password', $pw);
        }
        
        else
        {
            $this->db->where('username', $this->db->escape_str($u));
            $this->db->where('password', $this->db->escape_str($pw));
        }
        
        
        
        $this->db->limit(1);
        
        $query = $this->db->get('users');
        if ($query->num_rows() > 0)
        {
            $user = $query->row_array();
            $_SESSION['active'] = TRUE;
            $_SESSION['userid'] = $user['id'];
            $_SESSION['username'] = $user['username'];
            $_SESSION['email'] = $user['email'];
            $_SESSION['lastlogin'] = $user['last_login'];
            
            // update last_login
            $date = date('Y-m-d h:m:s');
            $data = array('last_login' => $date);
            $this->db->update('users', $data);
            
            return TRUE;
        }
        
        else
        {
            return FALSE;
        }
    }    
    
    function verifyAdmin($uid)
    {
        if ($_SESSION['active'] == TRUE)
        {
            $uid = $_SESSION['userid'];
            
            $this->db->select('user_id');
            $this->db->where('user_id', $uid);
            $this->db->limit(1);
            
            $query = $this->db->get('admins');
            if ($query->num_rows() > 0)
            {
                $_SESSION['admin'] = TRUE;
                return TRUE;
            }
            
            else
            {
                return FALSE;
            }
        }
        
        else
        {
            return FALSE;
        }
    }

    function verifySession()
    {
        if ( ! isset($_SESSION['admin']) || ! isset($_SESSION['active']) )
            {
                redirect('welcome');
            }
    }
    
}