防CC攻击：在3秒内连续刷新页面5次以上将指向本机

php代码

<?php
session_start();
$nowtime = time() ;
if (session_is_registered(&#39;lasttime&#39;))
{
 $lasttime = $_SESSION[&#39;lasttime&#39;];
 $times = $_SESSION[&#39;times&#39;] + 1;
 $_SESSION[&#39;times&#39;] = $times;
}else{
 $lasttime = $nowtime;
 $times = 1;
 $_SESSION[&#39;times&#39;] = $times;
 $_SESSION[&#39;lasttime&#39;] = $lasttime;
}

if (($nowtime - $lasttime)=5){
  header(sprintf("Location: %s",&#39;http://127.0.0.1&#39;));
  exit;
 }
}else{
 $times = 0;
 $_SESSION[&#39;lasttime&#39;] = $nowtime;
 $_SESSION[&#39;times&#39;] = $times;
}

?>