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Article:
  Ten Security Checks for PHP, Part 1
Subject:   get/post
Date:   2004-11-17 03:56:54
From:   Lancelotti
Response to: get/post

Cant you use this to security of your incluedes.


$page = "path_to_file/$_GET[page].php";
// put de get variable in string, and indicated de directory where your subpages are


if (!file_exists($page)) {
$page = "index.php";
}
// if file not exists use the index.php


include($page);
// include de file


Note. Include all your subpages in path_to_file and your extension may be .php

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  • get/post
    2004-11-17 15:05:41  Clancy Malcolm | O'Reilly Author [View]

    Lancelotti,

    The above code provides a little security - it limits people to only including PHP files from the local machine. However, a user can choose ANY PHP file on the machine (subject to the web server's account permissions) and include that file by using a value for page like '../../example'.

    You could prevent this by checking the value using a regular expression (maybe '^[a-z_]*$') or by using the realpath function to check that the resulting page is still in the desired directory.

    (Note that if you were using the safe_mode setting it would be a bit different, but may still be insecure).

    Hope this helps.

    Regards,
    Clancy