Android Secure Shred

obliterate.sh

#!/sbin/sh

# To be used with extreme caution.
# This script will utterly and totally obliterate any block device
# you pass to it. It was designed for use on Android for secure 
# wiping of devices, but could probably be used otherwise. 

# DO NOT USE THIS UNLESS YOU ARE ABSOLUTELY SURE OF WHAT YOU'RE DOING

help_text="usage: obliterate [partition]"

if [ -z "$1" ]; then
    echo "$help_text" >&2
    exit 1
fi

# must be a block device
if [ ! -b "$1" ]; then
    echo "$1 is not a block device; we can't obliterate it." >&2
    exit 1
fi

##################################
### ALL HAIL DESTROYER OF DISKS ##
##################################

echo "YOUR DISK IS ABOUT TO BE UTTERLY OBLITERATED, YOU HAVE 5 SECONDS TO CANCEL (Ctrl+C)"

sleep 6

# zero it out, baby
echo "$1: zeroing out everything..."
dd if=/dev/zero of=$1 bs=512

# random it out, baby
echo "$1: randoming out everything..."
dd if=/dev/urandom of=$1 bs=512

# final zero pass
echo "$1: final zero pass..."
dd if=/dev/zero of=$1 bs=512

echo "Your disk has been OBLITERATED."

exit 0