dedecms织梦安全代码让网站远离劫持

//禁止用户提交某些特殊变量
$ckvs = Array('_GET','_POST','_COOKIE','_FILES');
foreach($ckvs as $ckv){
  if(is_array($$ckv)){
    foreach($$ckv AS $key => $value)
      if(eregi("^(cfg_|globals)",$key)) unset(${$ckv}[$key]);
  }
}

//把get、post、cookie里的<? 替换成 <?
$ckvs = Array('_GET','_POST','_COOKIE');
foreach($ckvs as $ckv){
  if(is_array($$ckv)){
    foreach($$ckv AS $key => $value)
      if(!empty($value)){
        ${$ckv}[$key] = str_replace('<'.'?','&'.'lt;'.'?',$value);
        ${$ckv}[$key] = str_replace('?'.'>','?'.'&'.'gt;',${$ckv}[$key]); 内容来自dedecms
      }
      if(eregi("^cfg_|globals",$key)) unset(${$ckv}[$key]);
  }
}
//检测上传的文件中是否有PHP代码，有直接退出处理
if (is_array($_FILES)) {
foreach($_FILES AS $name => $value){
  ${$name} = $value['tmp_name'];
  $fp = @fopen(${$name},'r');
  $fstr = @fread($fp,filesize(${$name}));
  @fclose($fp);
  if($fstr!='' && ereg("<\?",$fstr)){
      echo "你上传的文件中含有危险内容，程序终止处理！";
      exit();
  }
}
}