#!/bin/bash

set -e # bail out at any error
if [ -z "${1}" ] ; then
	echo "Usage:"
	echo "	$0 <file>"
	echo "	$0 <device>"
	echo
	exit 1
fi

file=${1}
mountpoint=${2}

if [ -f "${file}" ] ; then
	for loop in /dev/loop* /dev/loop/* ; do
		if [ ! -b ${loop} ] ; then
			unset loop
			continue
		fi
		losetup "${loop}" "${file}" >/dev/null 2>&1 && break
		unset loop
	done
	if [ -z "${loop}" ] ; then
		echo "No free loopdevice found."
		exit 1
	fi
elif [ ! -b "${file}" ] ; then
	echo "Unknown filetype!"
	echo "${file} is neither a file nor a blockdevice!"
else
	loop=${file}
fi

pass="MOOP"
pass2="MEEP"
while [ "${pass}" != "${pass2}" ] ; do
	read -s -p "Enter passphrase: " pass
	echo
	read -s -p "Repeat: " pass2
	echo
done

pass="`echo ${pass} | md5sum`"
pass=${pass%% *}
encryptedname="`echo ${mountpoint} ${file} | md5sum`"
encryptedname=${encryptedname%% *}
while [ -e /dev/mapper/${encryptedname} ] ; do
	encryptedname="`echo ${encryptedname} ${file} | md5sum`"
	encryptedname=${encryptedname%% *}
# some day we _will_ find an unused one :)
done

echo 0 `/sbin/blockdev --getsize ${loop}` crypt aes-plain ${pass} 0 ${loop} 0 | /sbin/dmsetup create ${encryptedname}

y=0
read size < <( disktype ${loop} | grep ^Block )
size=${size##*(}
size=${size%% bytes*}
size=$(( ${size} / ( 1024*1024 ) ))
echo $size
#dd if=${loop} of=/dev/mapper/${encryptedname} bs=1M 2>/tmp/dd.${$} &
dd if=${loop} of=/dev/null bs=1M 2>/tmp/dd.${$} &
unset pid
while [ -z "${pid}" ] ; do
	sleep 1
	pid=`pidof dd`
done
while [ -e /proc/${pid} ] ; do
	sleep 4
	[ -e /proc/${pid} ] && kill -USR1 ${pid}
	sleep 1
	read records < <( tail -n 1 /tmp/dd.${$} )
	records="${records%%+*}"
	echo -en "\r${records} MB ($(( ${records}00 / ${size} ))%)"
done
echo
/sbin/dmsetup remove ${encryptedname}
[[ ${loop} == /dev/loop* ]] && /sbin/losetup -d ${loop}