#!/bin/bash

type_encrypted="encrypted"
entrosource="${LVP_ENTROPY_SOURCE}"

process_encrypted(){
	target="livesystem"

	for module in twofish blowfish serpent ; do
		eval "encryption_${module}=0"
		[ `lsmod | grep -c "loop_${module}"` -eq 0 ] && modprobe loop_${module} >/dev/null 2>&1 # fails for kernel >= 2.5.48 if module already loaded
		[ `lsmod | grep -c "loop_${module}"` -eq 1 ] && eval "encryption_${module}=1"
	done

	encryption_available=0
	[ ${encryption_twofish} -eq 1 -o ${encryption_blowfish} -eq 1 -o ${encryption_serpent} -eq 1 ] && \
		encryption_available=1

	if [ ${encryption_available} -eq 0 ] ; then
		echo "Sorry, you do not have loop-aes on your system. Please have a look at"
		echo "http://loop-aes.sourceforge.net"
		exit 1
	fi

	eval "avail=\${encryption_${LVP_ENCRYPTION}}"
	if [ "${avail}" == "0" ] ; then
		echo "Sorry, ${LVP_ENCRYPTION} is not available on your system."
		echo "Please check your kernel configuration."
		exit 1
	fi

	echo "Loading kernel module for linear mode"
	grep -q linear /proc/mdstat || modprobe linear
	if ! grep -q linear /proc/mdstat ; then
		echo "Sorry, you don't have linear RAID support in your kernel."
		echo "Since V0.4.2 this is required for encrypted LVPs to use"
		echo "available disk space more efficiently."
		exit 1
	fi

	echo -n "Checking necessary filesystem size ... "
	filesize=0

	while read file ; do
		[ ! -f "${file}" ] && continue
		thisfilesize=`ls -l "${file}" | sed 's,[ \t][ \t]*, ,g' | cut -f5 -d' '`
		filesize=$(( ${filesize} + ${thisfilesize} ))
	done < ${moviefiles}

	echo "${filesize} Byte (`human_readable ${filesize}`)"

	echo -n "Checking Livesystem size ... "
	livesize=`du -sb ${target} --exclude=lvp.data? | cut -f1`
	livesize=$(( ${livesize} + `du -sb isolinux | cut -f1` ))
	echo "`human_readable ${livesize}`"
	filesize=$(( ${filesize} + ${livesize} ))
	echo
	echo "Total space needed: $(( ${filesize} / 1024 / 1024 )) MB"

	if [ $(( ${filesize} / 1024 / 1024 )) -gt ${size} ] ; then
		echo
		echo "This may be more than fits onto your medium."
		echo "You specified ${size} MB to fit onto your medium."
		echo "If you are sure that this is okay, please continue."
		echo "If not, please truncate your filelist."
		confirm "Continue"
		[ ${?} -eq 1 ] && exit 1
	fi

	echo "Searching for free loopdevices ..."

	filesize=$(( ( ${size} * 1048576 ) - ${livesize} ))
	needed_pseudofs=$(( (${filesize} / 2147481600) + 1 ))
	needed_loopdevices=${needed_pseudofs}
	for loopdevice in /dev/loop/* ; do
		[ ${needed_loopdevices} -eq 0 ] && continue
		if losetup ${loopdevice} ${moviefiles} 2>/dev/null ; then
			# I reuse the ${moviefiles} tmpfile here since associating it
			# with a loopdevice doesn't do any harm
			echo "Using ${loopdevice}"
			eval "loopdevice_${needed_loopdevices}=\"${loopdevice}\""
			losetup -d ${loopdevice}
			needed_loopdevices=$(( ${needed_loopdevices} - 1 ))
		fi
	done

	if [ ${needed_loopdevices} -gt 0 ] ; then
		echo "Not enough free loop-devices found!"
		echo "Please either free ${needed_loopdevices} more loop-devices"
		echo "(check with losetup -a) or increase the"
		echo "number of available loop-devices."
		exit 1
	fi

	echo "Okay, Now creating files that will hold the pseudo filesystems"
	unset ddparam
	unset cpparam
	[ `dd --help | grep -c stat` -eq 1 ] && ddparam="conv=stat"
	[ `cp --help | grep -c "print copyprogress"` -eq 1 ] && cpparam="-D"

	if [ -e ${target}/lvp.data1 ] ; then
		for x in ${target}/lvp.data* ; do
			if [ ${x##*lvp.data} -gt ${needed_pseudofs} ] ; then\
				echo "Found ${x##*/}, but we don't need it. Deleting it."
				rm -f ${x}
			fi
		done
	fi

	filesystem=0
	while [ ${filesystem} -lt ${needed_pseudofs} ] ; do
		filesystem=$(( ${filesystem} + 1 ))
		echo "Filesystem ${filesystem} of ${needed_pseudofs}"
		file="${target}/lvp.data${filesystem}"

		if [ ${filesystem} -lt ${needed_pseudofs} ] ; then
			size=2147481600 # iso9660 limitation
		else
			size=$(( ${filesize} - ( ${filesystem} - 1 ) * 2147481600 ))
			size=$(( ( ${size} / 2048 ) * 2048 )) # so we have a round number
		fi

		if [ -f ${file} ] ; then
			thisfilesize=`ls -l "${file}" | sed 's,  *, ,g' | cut -f5 -d' '`
			if [ ${thisfilesize} -eq ${size} ] ; then
				echo "lvp.data${filesystem} already exists and has correct filesize. Using it."
			else	
				echo "lvp.data${filesystem} already exists but has wrong filesize. Deleting it"
				rm -f ${target}/lvp.data${filesystem}
			fi
		fi
		[ -f ${target}/lvp.data${filesystem} ] && continue
		dd if=/dev/${entrosource} of=${target}/lvp.data${filesystem} bs=2k count=$(( ${size} / 2048 )) ${ddparam}
	done

	echo "Creating mountpoint"
	rm -rf ${target}/mnt*
	mkdir ${target}/mnt1

	echo "Using ${LVP_ENCRYPTION} encryption."

	echo "Now I need a passphrase for encrypting the filesystems."
	passphrase="MEEP"
	passphrase_confirm="MOOP"
	while [ "${passphrase}" != "${passphrase_confirm}" ] ; do
		read -p "Enter passphrase: " -s passphrase
		echo
		if [ "${passphrase:20}" = "" ] ; then
			echo "The Passphrase must be at least 20 characters!"
			passphrase="MEEP"
			passphrase_confirm="MOOP"
			continue
		fi
		read -p "Confirm: " -s passphrase_confirm
		echo
		if [ "${passphrase}" != "${passphrase_confirm}" ] ; then
			echo "The passphrases do not match."
		fi
	done

	echo "Creating filesystems and mounting pseudo-filesystems"
	lvpdata=1
	while [ ${lvpdata} -le ${needed_pseudofs} ] ; do
		eval "lodev=\${loopdevice_${lvpdata}}"
		file="${target}/lvp.data${lvpdata}"

		echo "Setting up loopdevice ${lvpdata}"
		echo "${passphrase}" | losetup -p 0 -e ${LVP_ENCRYPTION}256 ${lodev} ${file}
		lvpdata=$(( ${lvpdata} + 1 ))
	done

	echo "Setting up linear device"
	mddev=""
	for x in /dev/md/* ; do
		[ ! -z "${mddev}" ] && break
		[ `mdadm --misc -Q ${x} | grep -c "not active"` -eq 1 ] && mddev="${x}"
	done
	mdloopdevs=""
	lvpdata=1
	while [ ${lvpdata} -le ${needed_pseudofs} ] ; do
		eval "mdloopdevs=\"\${mdloopdevs} \${loopdevice_${lvpdata}}\""
		lvpdata=$(( ${lvpdata} + 1 ))
	done
	${target}/sbin/mdadm --build ${mddev} -l linear --force -n ${needed_pseudofs} ${mdloopdevs}

	echo "Creating filesystem on ${mddev}"
	mkfs.ext2 -m 0 ${mddev} >/dev/null 2>&1
	echo "Mounting filesystem ${mddev}"
	mount ${mddev} ${target}/mnt1
	rm -rf ${target}/mnt1/*

	continue=0
	while read file ; do
		[ ! -f "${file}" ] && continue
		[ ${continue} -eq 1 ] && break

		unset targetdir
		thisfile=`ls -l "${file}" | sed 's,  *, ,g' | cut -f5 -d' '`
		for dir in ${target}/mnt? ; do # I leave this here for historical reasons, maybe we need it again some day
			avail=`df -P ${dir} | grep / | sed 's,  *, ,g' | cut -f4 -d' '`
			avail=$(( ${avail} * 1024 ))
			[ -z "${targetdir}" -a ${avail} -gt ${thisfile} ] && targetdir=${dir}
		done

		if [ -z "${targetdir}" ] ; then
			echo "Not enough space available for ${file}. Skipping remaining files." >&2
			continue=1
		fi
		[ ${continue} -eq 1 ] && continue

		echo "Copying ${file} to ${targetdir}/${file##*/}"
		cp ${cpparam} "${file}" "${targetdir}/${file##*/}"

		environment="`echo ${file} | tr '[. \-!]' '_'`"
		eval "export file_${environment##*/}=\"${targetdir#*${target}}/${file##*/}\""
	done < ${moviefiles}

	lvpxml=${target}/mnt1/lvp.xml
	process_create_lvpxml

	echo "Umounting filesystem ${mddev}"
	umount ${mddev}
	echo "Shutting down ${mddev}"
	mdadm -S ${mddev}

	lvpdata=${needed_pseudofs}
	while [ ${lvpdata} -ge 1 ] ; do
		eval "lodev=\${loopdevice_${lvpdata}}"
		echo "Shutting down loopdevice ${lodev}"
		losetup -d ${lodev}

		lvpdata=$(( ${lvpdata} - 1 ))
	done

	exit 0
}