#!/bin/bash
#
# Initialize encrypted swap space
#
# chkconfig: 12345 00 99
#
# description: initializes swap files with randomly chosen encryption. Right
#              now, it only works for partitions
#
#   FILE: cryptoswap
# AUTHOR: Adalbert Prokop <adalbert.prokop@gmx.de>
#   DATE: 11. June 2005
# 
# Copyright (C) 2005 Adalbert Prokop <adalbert.prokop@gmx.de>
# All rights reserved.
# 
# 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.
# 
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

# source function library
. /etc/rc.d/init.d/functions

myname=$(basename $0)

cryptsetup=/sbin/cryptsetup
mkswap=/sbin/mkswap
swaplist=/etc/sysconfig/swaps

if [ ! -x $cryptsetup ]; then
	cryptsetup=$(which cryptsetup)
	if [ -z "$cryptsetup" ]; then
		echo "$myname: no cryptsetup found."
		exit 1
	else
		echo "$myname: using $cryptsetup for cryptsetup"
	fi
fi

if [ ! -x $mkswap ]; then
	mkswap=$(which mkswap)
	if [ -z "$mkswap" ]; then
		echo "$myname: no mkswap found."
		exit 1
	else
		echo "$myname: using $mkswap for mkswap"
	fi
fi

if [ -f $swaplist ]; then
	swaps=$(cat $swaplist)
else
	echo "$myname: no swaplist found at $swaplist"
	exit 1
fi

activeswaps="$(cat /proc/swaps|awk -- "{print \$1}")"

# how are we called?
case "$1" in
	start)
		for swap in $swaps; do
			mapperfile="swap$(echo $swap|tr / -)"
			if ( echo "$activeswaps"|egrep -q "$mapperfile\$" ); then
				echo "Swap $swap seems to be already active."
			elif ( echo "$activeswaps" | grep -q "$swap\$" ); then
				echo "Swap $swap seeps to be already active and unencrypted."
			else
				echo -n "Creating swap for $swap "
				$cryptsetup -c aes-cbc-essiv:sha256 -d /dev/random create $mapperfile $swap && \
				$mkswap /dev/mapper/$mapperfile >& /dev/null && \
				/sbin/swapon /dev/mapper/$mapperfile && \
				daemon /bin/true || daemon /bin/false
				echo
			fi
		done
		;;
	stop)
		for swap in $swaps; do
			mapperfile="swap$(echo $swap|tr / -)"
			if ( echo "$activeswaps"|egrep -q "$mapperfile\$" ); then
				echo -n "Stopping swap on $swap "
				/sbin/swapoff /dev/mapper/$mapperfile && \
				$cryptsetup remove $mapperfile && \
				daemon /bin/true || daemon /bin/false
				echo
			else
				echo "Swap $swap does not seem to be active."
			fi
		done
		;;
	status)
		for swap in $swaps; do
			mapperfile="swap$(echo $swap|tr / -)"
			$cryptsetup status $mapperfile
		done
		;;
	restart)
		$0 stop
		$0 start
		;;
	*)
		echo "Usage: $myname {stop|start|restart|status}"
		exit 1
		;;
esac