The Lolcats, they are everywhere!

Mule — Fri, 07 Aug 2009 07:57:18 +0000

Do you use squid? Are your users under-appreciating the blissful goodness that is the LOLcat? Feel like educating them a bit? Add or replace the following line in /etc/squid/squid.conf:

url_rewrite_program /bin/sed -u -r s!^([^[:space:]]*\.(jp(e)?g|gif|png|tiff|bmp)).*$!http://icanhascheezburger.files.wordpress.com/2009/04/funny-pictures-cat-is-on-your-computer.jpg!

Enterprising bofh’s could use a script to download the referred image, modify it, place it somewhere in /var/www/html and have the rewritten url point to the new bastardised image for extra credit, like this guy did.

It takes a bit more work, so let’s go over the steps:
Make sure you’ve got a webserver running on the same box as your proxy
Add/modify this line in /etc/squid/squid.conf

url_rewrite_program /etc/squid/mirror.sh

Now make /var/www/html writable by the squid user:

setfacl -m u:squid:rwx /var/www/html

And last but not least add this file as /etc/squid/mirror.sh and make it executable:

#!/bin/bash
while read URL
do
    SURL=$(echo ${URL} | cut -d" " -f1)
    echo ${SURL} | egrep -qi "\.(jp(e)?g|gif|png|tiff|bmp|ico)$" &&
        (umask 002
         PIC=$$-${RANDOM}
         wget -q -O /tmp/${PIC} ${SURL}
         convert -quiet /tmp/${PIC} -flop /var/www/html/${PIC}.png &&;
            echo http://127.0.0.1/${PIC}.png
        ) || echo $URL
done

The end result:

Breaking Systems for Fun and Profit » Squid Squalor

The Lolcats, they are everywhere!