//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Script to block robots from a site (or part of it).
//
// To set it up, stick this script in the root of the heirachy you are
// protecting, and add the following lines to your .htaccess (assuming
// that the script is called botfree.php and in the root of the
// server):
//
// # Setup the URL rewriting engine.
// RewriteEngine On
// RewriteBase /
//
// # Block all robots
// RewriteRule ^robots\.txt$ - [L]
// RewriteRule ^botfree\.php$ - [L]
// RewriteRule ^botfree-set$ botfree.php [L]
// RewriteRule ^botfree-check botfree.php [L]
// RewriteCond %{HTTP_COOKIE} !HUMAN=yes [NC]
// RewriteRule ^(.*)$ botfree.php [L]
//
// The method used would be easy to forge; if this script ever became
// widespread then you'd probably need to do something with images.
// URLs
$SETURL = substr($_SERVER['PHP_SELF'], 0, -4) . '-set';
$CHKURL = substr($_SERVER['PHP_SELF'], 0, -4) . '-check';
// Utility functions
function bf_die($error) {
header('HTTP/1.1 $error');
die("$error\n");
}
function bf_decode_getvar($name) {
if (!isset($_GET[$name]))
bf_die('400 Bad Request');
return $_GET[$name];
}
function bf_decode_6d_getvar($name) {
$var = bf_decode_getvar($name);
if (!preg_match('/^\d{6}$/', $_GET[$name]))
bf_die('400 Bad Request');
return $_GET[$name];
}
function bf_redirect($relurl) {
$url = 'http://';
$url .= $_SERVER['SERVER_NAME'];
$port = $_SERVER['SERVER_PORT'];
if ($port != 80)
$url .= ":$port";
$url .= $relurl;
header('HTTP/1.1 302 Found');
header("Location: $url");
?>
302 Found
Found
The document has moved here.
Bot Free Zone
Bot Free Zone
Are you human?
To prove that you are human please enter the six-digit number from
the blue box into the textbox and hit continue.
Since you are using you may have to reload
the page afterwards.
This is in order to prevent robots (specifically badly behaved
robots) from spidering this site.
Why? Well, the main reason is that I don't want the content of this
site ending up on any search engines. Search engines use programs
called robots to gather webpages for indexing, robots which are
supposed to respect the Robots Exclusion
Standard. Well-behaved robots that do just that will not
attempt to spider this site. Unfortunatly, not all robots are so
well-behaved, and this page is designed to stop them in their
tracks: robots can't read and follow instructions just yet!
As well as search engines' bots this test also stops the more
insidious bots such as spambots, which harvest email addresses, and
spybots, which try to hunt for percieved violations of copyright or
trademark law. Stopping them was not the primary aim of this test,
but the fact that it does pleases me nontheless.
On other sites I passively block bad robots and ignore badly-behaved
search engines, but my wish that nothing on ths site ever gets
indexed means that I have to employ more draconian measures. I
apologise to my readers for this small indignity. For more
information about blocking bad robots please refer to Mark Pilgrim's
excellent How
to block spambots, ban spybots, and tell unwanted robots to go to
hell.
Error
Whoops, you got it wrong. If you are human then please feel free to
go back and try again.
Error
I tried to set a cookie to indicate that you are a human and not a
robot, but I failed. Please enable cookies in your browser and try
again.