php防cc攻击代码

//防cc攻击代码  放主入口文件
session_start();  
$ll_nowtime = $timestamp ;  
if (session_is_registered('ll_lasttime')){  
    $ll_lasttime = $_SESSION['ll_lasttime'];  
$ll_times = $_SESSION['ll_times'] + 1;  
$_SESSION['ll_times'] = $ll_times;  
}else{  
$ll_lasttime = $ll_nowtime;  
$ll_times = 1;  
$_SESSION['ll_times'] = $ll_times;  
$_SESSION['ll_lasttime'] = $ll_lasttime;  
}  
if (($ll_nowtime - $ll_lasttime)<3){  
if ($ll_times>=5){  
header(sprintf("Location: %s",'http://127.0.0.1'));  
exit;  
}  
}else{  
$ll_times = 0;  
$_SESSION['ll_lasttime'] = $ll_nowtime;  
$_SESSION['ll_times'] = $ll_times;  
}