360提供的php防注入代码

<?php
//Code By Safe3
function customError($errno, $errstr, $errfile, $errline)
{
  echo "<b>Error number:</b> [$errno],error on line $errline in $errfile<br />" ;
  die();
}
set_error_handler("customError",E_ERROR);
$getfilter="'|(and|or)\\b.+?(>|<|=|in|like)|\\/\\*.+?\\*\\/|<\\s*script\\b|\\bEXEC\\b|UNION.+?Select|Update.+?SET|Insert\\s+INTO.+?VALUES|(Select|Delete).+?FROM|(Create|Alter|Drop|TRUNCATE)\\s+(TABLE|DATABASE)" ;
$postfilter="\\b(and|or)\\b.{1,6}?(=|>|<|\\bin\\b|\\blike\\b)|\\/\\*.+?\\*\\/|<\\s*script\\b|\\bEXEC\\b|UNION.+?Select|Update.+?SET|Insert\\s+INTO.+?VALUES|(Select|Delete).+?FROM|(Create|Alter|Drop|TRUNCATE)\\s+(TABLE|DATABASE)" ;
$cookiefilter="\\b(and|or)\\b.{1,6}?(=|>|<|\\bin\\b|\\blike\\b)|\\/\\*.+?\\*\\/|<\\s*script\\b|\\bEXEC\\b|UNION.+?Select|Update.+?SET|Insert\\s+INTO.+?VALUES|(Select|Delete).+?FROM|(Create|Alter|Drop|TRUNCATE)\\s+(TABLE|DATABASE)" ;
function StopAttack($StrFiltKey,$StrFiltValue,$ArrFiltReq){ 

if(is_array($StrFiltValue))
{
  $StrFiltValue=implode($StrFiltValue);
}
if (preg_match("/".$ArrFiltReq."/is",$StrFiltValue)==1){
    //slog("<br><br>操作IP: ".$_SERVER["REMOTE_ADDR"]."<br>操作时间: ".strftime("%Y-%m-%d %H:%M:%S")."<br>操作页面:".$_SERVER["PHP_SELF"]."<br>提交方式: ".$_SERVER["REQUEST_METHOD"]."<br>提交参数: ".$StrFiltKey."<br>提交数据: ".$StrFiltValue);
    print "360websec notice:Illegal operation!" ;
    exit();
}
}
//$ArrPGC=array_merge($_GET,$_POST,$_COOKIE);
foreach($_GET as $key=>$value){
  StopAttack($key,$value,$getfilter);
}
foreach($_POST as $key=>$value){
  StopAttack($key,$value,$postfilter);
}
foreach($_COOKIE as $key=>$value){
  StopAttack($key,$value,$cookiefilter);
}
/*
if (file_exists('update360.php')) {
  echo "请重命名文件update360.php，防止黑客利用<br/>";
  die();
}
*/
function slog($logs)
{
  $toppath=$_SERVER["DOCUMENT_ROOT"]."/log.htm";
  $Ts=fopen($toppath,"a+");
  fputs($Ts,$logs."\r\n");
  fclose($Ts);
}