PHP防CC攻击实现代码总结

//代理IP直接退出
empty($_SERVER['HTTP_VIA']) or exit('Access Denied');
//防止快速刷新
session_start();
$seconds = '3'; //时间段[秒]
$refresh = '5'; //刷新次数
//设置监控变量
$cur_time = time();
if(isset($_SESSION['last_time'])){
$_SESSION['refresh_times'] += 1;
}else{
$_SESSION['refresh_times'] = 1;
$_SESSION['last_time'] = $cur_time;
}
//处理监控结果
if($cur_time - $_SESSION['last_time'] < $seconds){
if($_SESSION['refresh_times'] >= $refresh){
//跳转至攻击者服务器地址
header(sprintf('Location:%s', 'http://127.0.0.1'));
exit('Access Denied');
}
}else{
$_SESSION['refresh_times'] = 0;
$_SESSION['last_time'] = $cur_time;
}

$P_S_T = $t_array[0] + $t_array[1];
$timestamp = time();

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;
}

/*
* 防CC攻击郁闷到死，不死版。
*
* 如果每秒内网站刷新次数超过2次，延迟5秒后访问。
*/

$cc_min_nums = '1'; //次，刷新次数
$cc_url_time = '5'; //秒，延迟时间
//$cc_log = 'cc_log.txt'; //启用本行为记录日志
$cc_forward = 'http://localhost'; //释放到URL

//--------------------------------------------

//返回URL
$cc_uri = $_SERVER['REQUEST_URI']?$_SERVER['REQUEST_URI']:($_SERVER['PHP_SELF']?$_SERVER['PHP_SELF']:$_SERVER['SCRIPT_NAME']);
$site_url = 'http://'.$_SERVER ['HTTP_HOST'].$cc_uri;

//启用session
if( !isset( $_SESSION ) ) session_start();
$_SESSION["visiter"] = true;
if ($_SESSION["visiter"] <> true){
echo "";
//header("Location: ".$cc_forward);
exit;
}

$timestamp = time();
$cc_nowtime = $timestamp ;
if (session_is_registered('cc_lasttime')){
$cc_lasttime = $_SESSION['cc_lasttime'];
$cc_times = $_SESSION['cc_times'] + 1;
$_SESSION['cc_times'] = $cc_times;
}else{
$cc_lasttime = $cc_nowtime;
$cc_times = 1;
$_SESSION['cc_times'] = $cc_times;
$_SESSION['cc_lasttime'] = $cc_lasttime;
}

//获取真实IP
if (isset($_SERVER)){
$real_ip = $_SERVER['HTTP_X_FORWARDED_FOR'];
}else{
$real_ip = getenv("HTTP_X_FORWARDED_FOR");
}

//print_r($_SESSION);

//释放IP
if (($cc_nowtime - $cc_lasttime)<=0){
if ($cc_times>=$cc_min_nums){
if(!empty($cc_log)) cc_log(get_ip(), $real_ip, $cc_log, $cc_uri); //产生log
echo "Wait please, try again later!";
//printf('您的刷新过快，请稍后。');
//header("Location: ".$cc_forward);
exit;
}
}else{
$cc_times = 0;
$_SESSION['cc_lasttime'] = $cc_nowtime;
$_SESSION['cc_times'] = $cc_times;
}

//记录cc日志
function cc_log($client_ip, $real_ip, $cc_log, $cc_uri){
$temp_time = date("Y-m-d H:i:s", time() + 3600*8);

$temp_result = "[".$temp_time."] [client ".$client_ip."] ";
if($real_ip) $temp_result .= " [real ".$real_ip."] ";
$temp_result .= $cc_uri . "rn";

$handle = fopen ("$cc_log", "rb");
$oldcontent = fread($handle,filesize("$cc_log"));
fclose($handle);

$newcontent = $temp_result . $oldcontent;
$fhandle=fopen("$cc_log", "wb");
fwrite($fhandle,$newcontent,strlen($newcontent));
fclose($fhandle);
}

//获取在线IP
function get_ip() {
global $_C;

if(empty($_C['client_ip'])) {
if(getenv('HTTP_CLIENT_IP') && strcasecmp(getenv('HTTP_CLIENT_IP'), 'unknown')) {
$client_ip = getenv('HTTP_CLIENT_IP');
} elseif(getenv('HTTP_X_FORWARDED_FOR') && strcasecmp(getenv('HTTP_X_FORWARDED_FOR'), 'unknown')) {
$client_ip = getenv('HTTP_X_FORWARDED_FOR');
} elseif(getenv('REMOTE_ADDR') && strcasecmp(getenv('REMOTE_ADDR'), 'unknown')) {
$client_ip = getenv('REMOTE_ADDR');
} elseif(isset($_SERVER['REMOTE_ADDR']) && $_SERVER['REMOTE_ADDR'] && strcasecmp($_SERVER['REMOTE_ADDR'], 'unknown')) {
$client_ip = $_SERVER['REMOTE_ADDR'];
}
$_C['client_ip'] = $client_ip ? $client_ip : 'unknown';
}
return $_C['client_ip'];
}
?>