Tag: perl regex

Lighttpd block wget useragent for specific urls

last updated in Categories Ask nixCraft, lighttpd, Linux, Security, Tips, Tuning, UNIX

One of regular reader asks a question:

My website powered by Lighttpd web server. I’d like to block Wget useragent for entire my domain.com site except for /downloads/ url section. How do I configure lighttpd?

You need to use $HTTP filed useragent and url combination. Just open your lighttpd.conf file and append code as follows.

Lighttpd block useragent wget configuration

# vi /etc/lighttpd/lighttpd.conf
Append config directive as follows:

$HTTP["useragent"] =~ "Wget" {
        $HTTP["url"] !~ "^/download($|/)" {
                url.access-deny = ( "" )
        }
  }

Where,

  • $HTTP[“useragent”] : Match on useragent i.e. Wget
  • $HTTP[“url”] : Match on url section such as /download/*. If there are nested blocks, this must be the most inner block.
  • =~ : Perl style regular expression match
  • !~ : Perl style regular expression not match

Just restart the webserver, enter:
# /etc/init.d/lighttpd restart

Now user can run wget on http://domain.com/download/* urls but not on http://domain.com/file.html or http://domain.com/dir/file