添加wordpress后台验证功能

<?php

function bd_login_form()  
{  
?>  
    <p>  
        <label for="user_pass_2">身份认证<br />  
        <input type="password" name="pwd_2" id="user_pass_2" value="" size="20" tabindex="20" /></label>  
    </p>  
<?  
}  
add_action('login_form', 'bd_login_form');  

function bd_authenticate_username_password($user, $username = '', $password = '')  
{  
    if ( isset($_POST['log']) )  
    {  
        $bDone = false;  
        if ( isset( $_REQUEST['pwd_2'] ) )  
        {  
            $pwd2 = $_REQUEST['pwd_2'];  
            if ( $pwd2 === '123' ) // 自由修改认证码  
                $bDone = true;  
        }  
        if ( $bDone == false )  
        {  
            remove_filter('authenticate', 'wp_authenticate_username_password', 20, 3);  
            $error = new WP_Error();  
            $error->add('incorrect_password', __('<strong>错误</strong>：身份认证失败。'));  
            return $error;  
        }  
    }  
    return $user;  
}  
add_filter('authenticate', 'bd_authenticate_username_password');  

?>