Reorganizing components in source tree.

1 files changed, 1561 insertions, 0 deletions

diff --git a/components/9990-misc-helpers.sh b/components/9990-misc-helpers.sh
new file mode 100755
index 0000000..82099a4
--- /dev/null
+++ b/components/9990-misc-helpers.sh
@@ -0,0 +1,1561 @@
+#!/bin/sh
+
+#set -e
+
+file_pattern_matches()
+{
+	[ -e "$1" ]
+}
+
+is_live_path()
+{
+	DIRECTORY="${1}/${LIVE_MEDIA_PATH}"
+	for FILESYSTEM in squashfs ext2 ext3 ext4 xfs dir jffs
+	do
+		if file_pattern_matches "${DIRECTORY}/"*.${FILESYSTEM}
+		then
+			return 0
+		fi
+	done
+	return 1
+}
+
+matches_uuid ()
+{
+	if [ "${IGNORE_UUID}" ] || [ ! -e /conf/uuid.conf ]
+	then
+		return 0
+	fi
+
+	path="${1}"
+	uuid="$(cat /conf/uuid.conf)"
+
+	for try_uuid_file in "${path}/.disk/live-uuid"*
+	do
+		[ -e "${try_uuid_file}" ] || continue
+
+		try_uuid="$(cat "${try_uuid_file}")"
+
+		if [ "${uuid}" = "${try_uuid}" ]
+		then
+			return 0
+		fi
+	done
+
+	return 1
+}
+
+get_backing_device ()
+{
+	case "${1}" in
+		*.squashfs|*.ext2|*.ext3|*.ext4|*.jffs2)
+			echo $(setup_loop "${1}" "loop" "/sys/block/loop*" '0' "${LIVE_MEDIA_ENCRYPTION}" "${2}")
+			;;
+
+		*.dir)
+			echo "directory"
+			;;
+
+		*)
+			panic "Unrecognized live filesystem: ${1}"
+			;;
+	esac
+}
+
+mount_images_in_directory ()
+{
+	directory="${1}"
+	rootmnt="${2}"
+	mac="${3}"
+
+	if is_live_path "${directory}"
+	then
+		[ -n "${mac}" ] && adddirectory="${directory}/${LIVE_MEDIA_PATH}/${mac}"
+		setup_unionfs "${directory}/${LIVE_MEDIA_PATH}" "${rootmnt}" "${adddirectory}"
+	else
+		panic "No supported filesystem images found at /${LIVE_MEDIA_PATH}."
+	fi
+}
+
+is_nice_device ()
+{
+	sysfs_path="${1#/sys}"
+
+	if /sbin/udevadm test-builtin path_id "${sysfs_path}" | egrep -q "ID_PATH=(usb|pci-[^-]*-(ide|sas|scsi|usb|virtio)|platform-sata_mv|platform-orion-ehci|platform-mmc|platform-mxsdhci)"
+	then
+		return 0
+	elif echo "${sysfs_path}" | grep -q '^/block/vd[a-z]$'
+	then
+		return 0
+	elif echo ${sysfs_path} | grep -q "^/block/dm-"
+	then
+		return 0
+	elif echo ${sysfs_path} | grep -q "^/block/mtdblock"
+	then
+		return 0
+	fi
+
+	return 1
+}
+
+check_dev ()
+{
+	sysdev="${1}"
+	devname="${2}"
+	skip_uuid_check="${3}"
+
+	# support for fromiso=.../isofrom=....
+	if [ -n "$FROMISO" ]
+	then
+		ISO_DEVICE=$(dirname $FROMISO)
+		if ! [ -b $ISO_DEVICE ]
+		then
+			# to support unusual device names like /dev/cciss/c0d0p1
+			# as well we have to identify the block device name, let's
+			# do that for up to 15 levels
+			i=15
+			while [ -n "$ISO_DEVICE" ] && [ "$i" -gt 0 ]
+			do
+				ISO_DEVICE=$(dirname ${ISO_DEVICE})
+				[ -b "$ISO_DEVICE" ] && break
+				i=$(($i -1))
+		        done
+		fi
+
+		if [ "$ISO_DEVICE" = "/" ]
+		then
+			echo "Warning: device for bootoption fromiso= ($FROMISO) not found.">>/boot.log
+		else
+			fs_type=$(get_fstype "${ISO_DEVICE}")
+			if is_supported_fs ${fs_type}
+			then
+				mkdir /live/fromiso
+				mount -t $fs_type "$ISO_DEVICE" /live/fromiso
+				ISO_NAME="$(echo $FROMISO | sed "s|$ISO_DEVICE||")"
+				loopdevname=$(setup_loop "/live/fromiso/${ISO_NAME}" "loop" "/sys/block/loop*" "" '')
+				devname="${loopdevname}"
+			else
+				echo "Warning: unable to mount $ISO_DEVICE." >>/boot.log
+			fi
+		fi
+	fi
+
+	if [ -z "${devname}" ]
+	then
+		devname=$(sys2dev "${sysdev}")
+	fi
+
+	if [ -d "${devname}" ]
+	then
+		mount -o bind "${devname}" $mountpoint || continue
+
+		if is_live_path $mountpoint
+		then
+			echo $mountpoint
+			return 0
+		else
+			umount $mountpoint
+		fi
+	fi
+
+	IFS=","
+	for device in ${devname}
+	do
+		case "$device" in
+			*mapper*)
+				# Adding lvm support
+				if [ -x /scripts/local-top/lvm2 ]
+				then
+					ROOT="$device" resume="" /scripts/local-top/lvm2
+				fi
+				;;
+
+			/dev/md*)
+				# Adding raid support
+				if [ -x /scripts/local-top/mdadm ]
+				then
+					cp /conf/conf.d/md /conf/conf.d/md.orig
+					echo "MD_DEVS=$device " >> /conf/conf.d/md
+					/scripts/local-top/mdadm
+					mv /conf/conf.d/md.orig /conf/conf.d/md
+				fi
+				;;
+		esac
+	done
+	unset IFS
+
+	[ -n "$device" ] && devname="$device"
+
+	[ -e "$devname" ] || continue
+
+	if [ -n "${LIVE_MEDIA_OFFSET}" ]
+	then
+		loopdevname=$(setup_loop "${devname}" "loop" "/sys/block/loop*" "${LIVE_MEDIA_OFFSET}" '')
+		devname="${loopdevname}"
+	fi
+
+	fstype=$(get_fstype "${devname}")
+
+	if is_supported_fs ${fstype}
+	then
+		devuid=$(blkid -o value -s UUID "$devname")
+		[ -n "$devuid" ] && grep -qs "\<$devuid\>" $tried && continue
+		mount -t ${fstype} -o ro,noatime "${devname}" ${mountpoint} || continue
+		[ -n "$devuid" ] && echo "$devuid" >> $tried
+
+		if [ -n "${FINDISO}" ]
+		then
+			if [ -f ${mountpoint}/${FINDISO} ]
+			then
+				umount ${mountpoint}
+				mkdir -p /live/findiso
+				mount -t ${fstype} -o ro,noatime "${devname}" /live/findiso
+				loopdevname=$(setup_loop "/live/findiso/${FINDISO}" "loop" "/sys/block/loop*" 0 "")
+				devname="${loopdevname}"
+				mount -t iso9660 -o ro,noatime "${devname}" ${mountpoint}
+			else
+				umount ${mountpoint}
+			fi
+		fi
+
+		if is_live_path ${mountpoint} && \
+			([ "${skip_uuid_check}" ] || matches_uuid ${mountpoint})
+		then
+			echo ${mountpoint}
+			return 0
+		else
+			umount ${mountpoint} 2>/dev/null
+		fi
+	fi
+
+	if [ -n "${LIVE_MEDIA_OFFSET}" ]
+	then
+		losetup -d "${loopdevname}"
+	fi
+
+	return 1
+}
+
+find_livefs ()
+{
+	timeout="${1}"
+
+	# don't start autodetection before timeout has expired
+	if [ -n "${LIVE_MEDIA_TIMEOUT}" ]
+	then
+		if [ "${timeout}" -lt "${LIVE_MEDIA_TIMEOUT}" ]
+		then
+			return 1
+		fi
+	fi
+
+	# first look at the one specified in the command line
+	case "${LIVE_MEDIA}" in
+		removable-usb)
+			for sysblock in $(removable_usb_dev "sys")
+			do
+				for dev in $(subdevices "${sysblock}")
+				do
+					if check_dev "${dev}"
+					then
+						return 0
+					fi
+				done
+			done
+			return 1
+			;;
+
+		removable)
+			for sysblock in $(removable_dev "sys")
+			do
+				for dev in $(subdevices "${sysblock}")
+				do
+					if check_dev "${dev}"
+					then
+						return 0
+					fi
+				done
+			done
+			return 1
+			;;
+
+		*)
+			if [ ! -z "${LIVE_MEDIA}" ]
+			then
+				if check_dev "null" "${LIVE_MEDIA}" "skip_uuid_check"
+				then
+					return 0
+				fi
+			fi
+			;;
+	esac
+
+	# or do the scan of block devices
+	# prefer removable devices over non-removable devices, so scan them first
+	devices_to_scan="$(removable_dev 'sys') $(non_removable_dev 'sys')"
+
+	for sysblock in $devices_to_scan
+	do
+		devname=$(sys2dev "${sysblock}")
+		[ -e "$devname" ] || continue
+		fstype=$(get_fstype "${devname}")
+
+		if /lib/udev/cdrom_id ${devname} > /dev/null
+		then
+			if check_dev "null" "${devname}"
+			then
+				return 0
+			fi
+		elif is_nice_device "${sysblock}"
+		then
+			for dev in $(subdevices "${sysblock}")
+			do
+				if check_dev "${dev}"
+				then
+					return 0
+				fi
+			done
+		elif [ "${fstype}" = "squashfs" -o \
+			"${fstype}" = "btrfs" -o \
+			"${fstype}" = "ext2" -o \
+			"${fstype}" = "ext3" -o \
+			"${fstype}" = "ext4" -o \
+			"${fstype}" = "jffs2" ]
+		then
+			# This is an ugly hack situation, the block device has
+			# an image directly on it.  It's hopefully
+			# live-boot, so take it and run with it.
+			ln -s "${devname}" "${devname}.${fstype}"
+			echo "${devname}.${fstype}"
+			return 0
+		fi
+	done
+
+	return 1
+}
+
+really_export ()
+{
+	STRING="${1}"
+	VALUE="$(eval echo -n \${$STRING})"
+
+	if [ -f /live.vars ] && grep -sq "export ${STRING}" /live.vars
+	then
+		sed -i -e 's/\('${STRING}'=\).*$/\1'${VALUE}'/' /live.vars
+	else
+		echo "export ${STRING}=\"${VALUE}\"" >> /live.vars
+	fi
+
+	eval export "${STRING}"="${VALUE}"
+}
+
+is_in_list_separator_helper ()
+{
+	local sep element list
+	sep=${1}
+	shift
+	element=${1}
+	shift
+	list=${*}
+	echo ${list} | grep -qe "^\(.*${sep}\)\?${element}\(${sep}.*\)\?$"
+}
+
+is_in_space_sep_list ()
+{
+	local element
+	element=${1}
+	shift
+	is_in_list_separator_helper "[[:space:]]" "${element}" "${*}"
+}
+
+is_in_comma_sep_list ()
+{
+	local element
+	element=${1}
+	shift
+	is_in_list_separator_helper "," "${element}" "${*}"
+}
+
+sys2dev ()
+{
+	sysdev=${1#/sys}
+	echo "/dev/$($udevinfo -q name -p ${sysdev} 2>/dev/null|| echo ${sysdev##*/})"
+}
+
+subdevices ()
+{
+	sysblock=${1}
+	r=""
+
+	for dev in "${sysblock}"/* "${sysblock}"
+	do
+		if [ -e "${dev}/dev" ]
+		then
+			r="${r} ${dev}"
+		fi
+	done
+
+	echo ${r}
+}
+
+storage_devices()
+{
+	black_listed_devices="${1}"
+	white_listed_devices="${2}"
+
+	for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "loop|ram|fd")
+	do
+		fulldevname=$(sys2dev "${sysblock}")
+
+		if is_in_space_sep_list ${fulldevname} ${black_listed_devices} || \
+			[ -n "${white_listed_devices}" ] && \
+			! is_in_space_sep_list ${fulldevname} ${white_listed_devices}
+		then
+			# skip this device entirely
+			continue
+		fi
+
+		for dev in $(subdevices "${sysblock}")
+		do
+			devname=$(sys2dev "${dev}")
+
+			if is_in_space_sep_list ${devname} ${black_listed_devices}
+			then
+				# skip this subdevice
+				continue
+			else
+				echo "${devname}"
+			fi
+		done
+	done
+}
+
+is_supported_fs ()
+{
+	fstype="${1}"
+
+	# Validate input first
+	if [ -z "${fstype}" ]
+	then
+		return 1
+	fi
+
+	# Try to look if it is already supported by the kernel
+	if grep -q ${fstype} /proc/filesystems
+	then
+		return 0
+	else
+		# Then try to add support for it the gentle way using the initramfs capabilities
+		modprobe ${fstype}
+		if grep -q ${fstype} /proc/filesystems
+		then
+			return 0
+		# Then try the hard way if /root is already reachable
+		else
+			kmodule="/root/lib/modules/`uname -r`/${fstype}/${fstype}.ko"
+			if [ -e "${kmodule}" ]
+			then
+				insmod "${kmodule}"
+				if grep -q ${fstype} /proc/filesystems
+				then
+					return 0
+				fi
+			fi
+		fi
+	fi
+
+	return 1
+}
+
+get_fstype ()
+{
+	/sbin/blkid -s TYPE -o value $1 2>/dev/null
+}
+
+where_is_mounted ()
+{
+	device=${1}
+	# return first found
+	grep -m1 "^${device} " /proc/mounts | cut -f2 -d ' '
+}
+
+trim_path ()
+{
+	# remove all unnecessary /:s in the path, including last one (except
+	# if path is just "/")
+	echo ${1} | sed 's|//\+|/|g' | sed 's|^\(.*[^/]\)/$|\1|'
+}
+
+what_is_mounted_on ()
+{
+	local dir
+	dir="$(trim_path ${1})"
+	grep -m1 "^[^ ]\+ ${dir} " /proc/mounts | cut -d' ' -f1
+}
+
+chown_ref ()
+{
+	local reference targets owner
+	reference="${1}"
+	shift
+	targets=${@}
+	owner=$(stat -c %u:%g "${reference}")
+	chown -h ${owner} ${targets}
+}
+
+chmod_ref ()
+{
+	local reference targets rights
+	reference="${1}"
+	shift
+	targets=${@}
+	rights=$(stat -c %a "${reference}")
+	chmod ${rights} ${targets}
+}
+
+lastline ()
+{
+	while read lines
+	do
+		line=${lines}
+	done
+
+	echo "${line}"
+}
+
+base_path ()
+{
+	testpath="${1}"
+	mounts="$(awk '{print $2}' /proc/mounts)"
+	testpath="$(busybox realpath ${testpath})"
+
+	while true
+	do
+		if echo "${mounts}" | grep -qs "^${testpath}"
+		then
+			set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
+			echo ${1}
+			break
+		else
+			testpath=$(dirname $testpath)
+		fi
+	done
+}
+
+fs_size ()
+{
+	# Returns used/free fs kbytes + 5% more
+	# You could pass a block device as ${1} or the mount point as ${2}
+
+	dev="${1}"
+	mountp="${2}"
+	used="${3}"
+
+	if [ -z "${mountp}" ]
+	then
+		mountp="$(where_is_mounted ${dev})"
+
+		if [ -z "${mountp}" ]
+		then
+			mountp="/mnt/tmp_fs_size"
+
+			mkdir -p "${mountp}"
+			mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}" || log_warning_msg "cannot mount -t $(get_fstype ${dev}) -o ro ${dev} ${mountp}"
+
+			doumount=1
+		fi
+	fi
+
+	if [ "${used}" = "used" ]
+	then
+		size=$(du -ks ${mountp} | cut -f1)
+		size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
+	else
+		# free space
+		size="$(df -kP | grep -s ${mountp} | awk '{print $4}')"
+	fi
+
+	if [ -n "${doumount}" ]
+	then
+		umount "${mountp}" || log_warning_msg "cannot umount ${mountp}"
+		rmdir "${mountp}"
+	fi
+
+	echo "${size}"
+}
+
+load_keymap ()
+{
+	# Load custom keymap
+	if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
+	then
+		loadkeys --quiet /etc/boottime.kmap.gz
+	fi
+}
+
+setup_loop ()
+{
+	local fspath module pattern offset encryption readonly
+	fspath=${1}
+	module=${2}
+	pattern=${3}
+	offset=${4}
+	encryption=${5}
+	readonly=${6}
+
+	# the output of setup_loop is evaluated in other functions,
+	# modprobe leaks kernel options like "libata.dma=0"
+	# as "options libata dma=0" on stdout, causing serious
+	# problems therefor, so instead always avoid output to stdout
+	modprobe -q -b "${module}" 1>/dev/null
+
+	udevadm settle
+
+	for loopdev in ${pattern}
+	do
+		if [ "$(cat ${loopdev}/size)" -eq 0 ]
+		then
+			dev=$(sys2dev "${loopdev}")
+			options=''
+
+			if [ -n "${readonly}" ]
+			then
+				if losetup --help 2>&1 | grep -q -- "-r\b"
+				then
+					options="${options} -r"
+				fi
+			fi
+
+			if [ -n "${offset}" ] && [ 0 -lt "${offset}" ]
+			then
+				options="${options} -o ${offset}"
+			fi
+
+			if [ -z "${encryption}" ]
+			then
+				losetup ${options} "${dev}" "${fspath}"
+			else
+				# Loop AES encryption
+				while true
+				do
+					load_keymap
+
+					echo -n "Enter passphrase for root filesystem: " >&6
+					read -s passphrase
+					echo "${passphrase}" > /tmp/passphrase
+					unset passphrase
+					exec 9</tmp/passphrase
+					/sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
+					error=${?}
+					exec 9<&-
+					rm -f /tmp/passphrase
+
+					if [ 0 -eq ${error} ]
+					then
+						unset error
+						break
+					fi
+
+					echo
+					echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
+					read answer
+
+					if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
+					then
+						unset answer
+						break
+					fi
+				done
+			fi
+
+			echo "${dev}"
+			return 0
+		fi
+	done
+
+	panic "No loop devices available"
+}
+
+try_mount ()
+{
+	dev="${1}"
+	mountp="${2}"
+	opts="${3}"
+	fstype="${4}"
+
+	old_mountp="$(where_is_mounted ${dev})"
+
+	if [ -n "${old_mountp}" ]
+	then
+		if [ "${opts}" != "ro" ]
+		then
+			mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
+		fi
+
+		mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
+	else
+		if [ -z "${fstype}" ]
+		then
+			fstype=$(get_fstype "${dev}")
+		fi
+		mount -t "${fstype}" -o "${opts}" "${dev}" "${mountp}" || \
+		( echo "SKIPPING: Cannot mount ${dev} on ${mountp}, fstype=${fstype}, options=${opts}" > boot.log && return 0 )
+	fi
+}
+
+# Try to mount $device to the place expected by live-boot. If $device
+# is already mounted somewhere, move it to the expected place. If
+# we're only probing $device (to check if it has custom persistence)
+# $probe should be set, which suppresses warnings upon failure. On
+# success, print the mount point for $device.
+mount_persistence_media ()
+{
+	local device probe backing old_backing fstype mount_opts
+	device=${1}
+	probe=${2}
+
+	backing="/live/persistence/$(basename ${device})"
+
+	mkdir -p "${backing}"
+	old_backing="$(where_is_mounted ${device})"
+	if [ -z "${old_backing}" ]
+	then
+		fstype="$(get_fstype ${device})"
+		mount_opts="rw,noatime"
+		if [ -n "${PERSISTENCE_READONLY}" ]
+		then
+			mount_opts="ro,noatime"
+		fi
+		if mount -t "${fstype}" -o "${mount_opts}" "${device}" "${backing}" >/dev/null
+		then
+			echo ${backing}
+			return 0
+		else
+			[ -z "${probe}" ] && log_warning_msg "Failed to mount persistence media ${device}"
+			rmdir "${backing}"
+			return 1
+		fi
+	elif [ "${backing}" != "${old_backing}" ]
+	then
+		if mount --move ${old_backing} ${backing} >/dev/null
+		then
+			echo ${backing}
+			return 0
+		else
+			[ -z "${probe}" ] && log_warning_msg "Failed to move persistence media ${device}"
+			rmdir "${backing}"
+			return 1
+		fi
+	else
+		# This means that $device has already been mounted on
+		# the place expected by live-boot, so we're done.
+		echo ${backing}
+		return 0
+	fi
+}
+
+close_persistence_media ()
+{
+	local device backing
+	device=${1}
+	backing="$(where_is_mounted ${device})"
+
+	if [ -d "${backing}" ]
+	then
+		umount "${backing}" >/dev/null 2>&1
+		rmdir "${backing}" >/dev/null 2>&1
+	fi
+
+	if is_active_luks_mapping ${device}
+	then
+		/sbin/cryptsetup luksClose ${device}
+	fi
+}
+
+open_luks_device ()
+{
+	dev="${1}"
+	name="$(basename ${dev})"
+	opts="--key-file=-"
+	if [ -n "${PERSISTENCE_READONLY}" ]
+	then
+		opts="${opts} --readonly"
+	fi
+
+	if /sbin/cryptsetup status "${name}" >/dev/null 2>&1
+	then
+		re="^[[:space:]]*device:[[:space:]]*\([^[:space:]]*\)$"
+		opened_dev=$(cryptsetup status ${name} 2>/dev/null | grep "${re}" | sed "s|${re}|\1|")
+		if [ "${opened_dev}" = "${dev}" ]
+		then
+			luks_device="/dev/mapper/${name}"
+			echo ${luks_device}
+			return 0
+		else
+			log_warning_msg "Cannot open luks device ${dev} since ${opened_dev} already is opened with its name"
+			return 1
+		fi
+	fi
+
+	load_keymap
+
+	while true
+	do
+		/lib/cryptsetup/askpass "Enter passphrase for ${dev}: " | \
+			/sbin/cryptsetup -T 1 luksOpen ${dev} ${name} ${opts}
+
+		if [ 0 -eq ${?} ]
+		then
+			luks_device="/dev/mapper/${name}"
+			echo ${luks_device}
+			return 0
+		fi
+
+		echo >&6
+		echo -n "There was an error decrypting ${dev} ... Retry? [Y/n] " >&6
+		read answer
+
+		if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
+		then
+			return 2
+		fi
+	done
+}
+
+get_gpt_name ()
+{
+    local dev
+    dev="${1}"
+    /sbin/blkid -s PART_ENTRY_NAME -p -o value ${dev} 2>/dev/null
+}
+
+is_gpt_device ()
+{
+    local dev
+    dev="${1}"
+    [ "$(/sbin/blkid -s PART_ENTRY_SCHEME -p -o value ${dev} 2>/dev/null)" = "gpt" ]
+}
+
+probe_for_gpt_name ()
+{
+	local overlays dev gpt_dev gpt_name
+	overlays="${1}"
+	dev="${2}"
+
+	gpt_dev="${dev}"
+	if is_active_luks_mapping ${dev}
+	then
+		# if $dev is an opened luks device, we need to check
+		# GPT stuff on the backing device
+		gpt_dev=$(get_luks_backing_device "${dev}")
+	fi
+
+	if ! is_gpt_device ${gpt_dev}
+	then
+		return
+	fi
+
+	gpt_name=$(get_gpt_name ${gpt_dev})
+	for label in ${overlays}
+	do
+		if [ "${gpt_name}" = "${label}" ]
+		then
+			echo "${label}=${dev}"
+		fi
+	done
+}
+
+probe_for_fs_label ()
+{
+	local overlays dev
+	overlays="${1}"
+	dev="${2}"
+
+	for label in ${overlays}
+	do
+		if [ "$(/sbin/blkid -s LABEL -o value $dev 2>/dev/null)" = "${label}" ]
+		then
+			echo "${label}=${dev}"
+		fi
+	done
+}
+
+probe_for_file_name ()
+{
+	local overlays dev ret backing
+	overlays="${1}"
+	dev="${2}"
+
+	ret=""
+	backing="$(mount_persistence_media ${dev} probe)"
+	if [ -z "${backing}" ]
+	then
+	    return
+	fi
+
+	for label in ${overlays}
+	do
+		path=${backing}/${PERSISTENCE_PATH}${label}
+		if [ -f "${path}" ]
+		then
+			local loopdev
+			loopdev=$(setup_loop "${path}" "loop" "/sys/block/loop*")
+			ret="${ret} ${label}=${loopdev}"
+		fi
+	done
+
+	if [ -n "${ret}" ]
+	then
+		echo ${ret}
+	else
+		# unmount and remove mountpoint
+		umount ${backing} > /dev/null 2>&1 || true
+		rmdir ${backing} > /dev/null 2>&1 || true
+	fi
+}
+
+find_persistence_media ()
+{
+	# Scans devices for overlays, and returns a whitespace
+	# separated list of how to use them. Only overlays with a partition
+	# label or file name in ${overlays} are returned.
+	#
+	# When scanning a LUKS device, the user will be asked to enter the
+	# passphrase; on failure to enter it, or if no persistence partitions
+	# or files were found, the LUKS device is closed.
+	#
+	# For all other cases (overlay partition and overlay file) the
+	# return value is "${label}=${device}", where ${device} a device that
+	# can mount the content. In the case of an overlay file, the device
+	# containing the file will remain mounted as a side-effect.
+	#
+	# No devices in ${black_listed_devices} will be scanned, and if
+	# ${white_list_devices} is non-empty, only devices in it will be
+	# scanned.
+
+	local overlays white_listed_devices ret black_listed_devices
+	overlays="${1}"
+	white_listed_devices="${2}"
+	ret=""
+
+	black_listed_devices="$(what_is_mounted_on /live/medium) $(what_is_mounted_on /live/findiso) $(what_is_mounted_on /live/fromiso)"
+
+	for dev in $(storage_devices "${black_listed_devices}" "${white_listed_devices}")
+	do
+		local result luks_device
+		result=""
+
+		luks_device=""
+		# Check if it's a luks device; we'll have to open the device
+		# in order to probe any filesystem it contains, like we do
+		# below. activate_custom_mounts() also depends on that any luks
+		# device already has been opened.
+		if is_in_comma_sep_list luks ${PERSISTENCE_ENCRYPTION} && is_luks_partition ${dev}
+		then
+			if luks_device=$(open_luks_device "${dev}")
+			then
+				dev="${luks_device}"
+			else
+				# skip $dev since we failed/chose not to open it
+				continue
+			fi
+		elif ! is_in_comma_sep_list none ${PERSISTENCE_ENCRYPTION}
+		then
+			# skip $dev since we don't allow unencrypted storage
+			continue
+		fi
+
+		# Probe for matching GPT partition names or filesystem labels
+		if is_in_comma_sep_list filesystem ${PERSISTENCE_STORAGE}
+		then
+			result=$(probe_for_gpt_name "${overlays}" ${dev})
+			if [ -n "${result}" ]
+			then
+				ret="${ret} ${result}"
+				continue
+			fi
+
+			result=$(probe_for_fs_label "${overlays}" ${dev})
+			if [ -n "${result}" ]
+			then
+				ret="${ret} ${result}"
+				continue
+			fi
+		fi
+
+		# Probe for files with matching name on mounted partition
+		if is_in_comma_sep_list file ${PERSISTENCE_STORAGE}
+		then
+			result=$(probe_for_file_name "${overlays}" ${dev})
+			if [ -n "${result}" ]
+			then
+			        local loopdevice
+				loopdevice=${result##*=}
+			        if is_in_comma_sep_list luks ${PERSISTENCE_ENCRYPTION} && is_luks_partition ${loopdevice}
+				then
+				        local luksfile
+					luksfile=""
+					if luksfile=$(open_luks_device "${loopdevice}")
+					then
+					        result=${result%%=*}
+						result="${result}=${luksfile}"
+					else
+					        losetup -d $loopdevice
+						result=""
+					fi
+				fi
+				ret="${ret} ${result}"
+				continue
+			fi
+		fi
+
+		# Close luks device if it isn't used
+		if [ -z "${result}" ] && [ -n "${luks_device}" ] && is_active_luks_mapping "${luks_device}"
+		then
+			/sbin/cryptsetup luksClose "${luks_device}"
+		fi
+	done
+
+	if [ -n "${ret}" ]
+	then
+		echo ${ret}
+	fi
+}
+
+get_mac ()
+{
+	mac=""
+
+	for adaptor in /sys/class/net/*
+	do
+		status="$(cat ${adaptor}/iflink)"
+
+		if [ "${status}" -eq 2 ]
+		then
+			mac="$(cat ${adaptor}/address)"
+			mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
+		fi
+	done
+
+	echo ${mac}
+}
+
+is_luks_partition ()
+{
+	device="${1}"
+	/sbin/cryptsetup isLuks "${device}" 1>/dev/null 2>&1
+}
+
+is_active_luks_mapping ()
+{
+	device="${1}"
+	/sbin/cryptsetup status "${device}" 1>/dev/null 2>&1
+}
+
+get_luks_backing_device ()
+{
+	device=${1}
+	cryptsetup status ${device} 2> /dev/null | \
+		awk '{if ($1 == "device:") print $2}'
+}
+
+removable_dev ()
+{
+	output_format="${1}"
+	want_usb="${2}"
+	ret=
+
+	for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
+	do
+		dev_ok=
+		if [ "$(cat ${sysblock}/removable)" = "1" ]
+		then
+			if [ -z "${want_usb}" ]
+			then
+				dev_ok="true"
+			else
+				if readlink ${sysblock} | grep -q usb
+				then
+					dev_ok="true"
+				fi
+			fi
+		fi
+
+		if [ "${dev_ok}" = "true" ]
+		then
+			case "${output_format}" in
+				sys)
+					ret="${ret} ${sysblock}"
+					;;
+				*)
+					devname=$(sys2dev "${sysblock}")
+					ret="${ret} ${devname}"
+					;;
+			esac
+		fi
+	done
+
+	echo "${ret}"
+}
+
+removable_usb_dev ()
+{
+	output_format="${1}"
+
+	removable_dev "${output_format}" "want_usb"
+}
+
+non_removable_dev ()
+{
+	output_format="${1}"
+	ret=
+
+	for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
+	do
+		if [ "$(cat ${sysblock}/removable)" = "0" ]
+		then
+			case "${output_format}" in
+				sys)
+					ret="${ret} ${sysblock}"
+					;;
+				*)
+					devname=$(sys2dev "${sysblock}")
+					ret="${ret} ${devname}"
+					;;
+			esac
+		fi
+	done
+
+	echo "${ret}"
+}
+
+link_files ()
+{
+	# create source's directory structure in dest, and recursively
+	# create symlinks in dest to to all files in source. if mask
+	# is non-empty, remove mask from all source paths when
+	# creating links (will be necessary if we change root, which
+	# live-boot normally does (into $rootmnt)).
+	local src_dir dest_dir src_transform
+
+	# remove multiple /:s and ensure ending on /
+	src_dir="$(trim_path ${1})/"
+	dest_dir="$(trim_path ${2})/"
+	src_transform="${3}"
+
+	# This check can only trigger on the inital, non-recursive call since
+	# we create the destination before recursive calls
+	if [ ! -d "${dest_dir}" ]
+	then
+		log_warning_msg "Must link_files into a directory"
+		return
+	fi
+
+	find "${src_dir}" -mindepth 1 -maxdepth 1 | \
+	while read src
+	do
+		local dest final_src
+		dest="${dest_dir}$(basename "${src}")"
+		if [ -d "${src}" ]
+		then
+			if [ -z "$(ls -A "${src}")" ]
+			then
+				continue
+			fi
+			if [ ! -d "${dest}" ]
+			then
+				mkdir -p "${dest}"
+				chown_ref "${src}" "${dest}"
+				chmod_ref "${src}" "${dest}"
+			fi
+			link_files "${src}" "${dest}" "${src_transform}"
+		else
+			final_src=${src}
+			if [ -n "${src_transform}" ]
+			then
+				final_src="$(echo ${final_src} | sed "${src_transform}")"
+			fi
+			rm -rf "${dest}" 2> /dev/null
+			ln -s "${final_src}" "${dest}"
+			chown_ref "${src}" "${dest}"
+		fi
+	done
+}
+
+do_union ()
+{
+	local unionmountpoint unionrw unionro
+	unionmountpoint="${1}"	# directory where the union is mounted
+	shift
+	unionrw="${1}"		# branch where the union changes are stored
+	shift
+	unionro="${*}"		# space separated list of read-only branches (optional)
+
+	case "${UNIONTYPE}" in
+		aufs)
+			rw_opt="rw"
+			ro_opt="rr+wh"
+			noxino_opt="noxino"
+			;;
+
+		unionfs-fuse)
+			rw_opt="RW"
+			ro_opt="RO"
+			;;
+
+		*)
+			rw_opt="rw"
+			ro_opt="ro"
+			;;
+	esac
+
+	case "${UNIONTYPE}" in
+		unionfs-fuse)
+			unionmountopts="-o cow -o noinitgroups -o default_permissions -o allow_other -o use_ino -o suid"
+			unionmountopts="${unionmountopts} ${unionrw}=${rw_opt}"
+			if [ -n "${unionro}" ]
+			then
+				for rofs in ${unionro}
+				do
+					unionmountopts="${unionmountopts}:${rofs}=${ro_opt}"
+				done
+			fi
+			( sysctl -w fs.file-max=391524 ; ulimit -HSn 16384
+			unionfs-fuse ${unionmountopts} "${unionmountpoint}" ) && \
+			( mkdir -p /run/sendsigs.omit.d
+			pidof unionfs-fuse >> /run/sendsigs.omit.d/unionfs-fuse || true )
+			;;
+
+		overlayfs)
+			# XXX: can multiple unionro be used? (overlayfs only handles two dirs, but perhaps they can be chained?)
+			# XXX: and can unionro be optional? i.e. can overlayfs skip lowerdir?
+			if echo ${unionro} | grep -q " "
+			then
+				panic "Multiple lower filesystems are currently not supported with overlayfs (unionro = ${unionro})."
+			elif [ -z "${unionro}"	]
+			then
+				panic "Overlayfs needs at least one lower filesystem (read-only branch)."
+			fi
+			unionmountopts="-o noatime,lowerdir=${unionro},upperdir=${unionrw}"
+			mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
+			;;
+
+		*)
+			unionmountopts="-o noatime,${noxino_opt},dirs=${unionrw}=${rw_opt}"
+			if [ -n "${unionro}" ]
+			then
+				for rofs in ${unionro}
+				do
+					unionmountopts="${unionmountopts}:${rofs}=${ro_opt}"
+				done
+			fi
+			mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
+			;;
+	esac
+}
+
+get_custom_mounts ()
+{
+	# Side-effect: leaves $devices with persistence.conf mounted in /live/persistence
+	# Side-effect: prints info to file $custom_mounts
+
+	local custom_mounts devices bindings links
+	custom_mounts=${1}
+	shift
+	devices=${@}
+
+	bindings="/tmp/bindings.list"
+	links="/tmp/links.list"
+	rm -rf ${bindings} ${links} 2> /dev/null
+
+	for device in ${devices}
+	do
+		if [ ! -b "${device}" ]
+		then
+			continue
+		fi
+
+		local device_name backing include_list
+		device_name="$(basename ${device})"
+		backing=$(mount_persistence_media ${device})
+		if [ -z "${backing}" ]
+		then
+			continue
+		fi
+
+		if [ -r "${backing}/${persistence_list}" ]
+		then
+			include_list="${backing}/${persistence_list}"
+		elif [ -r "${backing}/${old_persistence_list}" ]
+		then
+			include_list="${backing}/${old_persistence_list}"
+		else
+			continue
+		fi
+
+		if [ -n "${LIVE_BOOT_DEBUG}" ] && [ -e "${include_list}" ]
+		then
+			cp ${include_list} /live/persistence/${persistence_list}.${device_name}
+		fi
+
+		while read dir options # < ${include_list}
+		do
+			if echo ${dir} | grep -qe "^[[:space:]]*\(#.*\)\?$"
+			then
+				# skipping empty or commented lines
+				continue
+			fi
+
+			if trim_path ${dir} | grep -q -e "^[^/]" -e "^/lib" -e "^/lib/live\(/.*\)\?$" -e "^/\(.*/\)\?\.\.\?\(/.*\)\?$"
+			then
+				log_warning_msg "Skipping unsafe custom mount ${dir}: must be an absolute path containing neither the \".\" nor \"..\" special dirs, and cannot be \"/lib\", or \"/lib/live\" or any of its sub-directories."
+				continue
+			fi
+
+			local opt_source opt_link source full_source full_dest
+			opt_source=""
+			opt_link=""
+			for opt in $(echo ${options} | tr ',' ' ');
+			do
+				case "${opt}" in
+					source=*)
+						opt_source=${opt#source=}
+						;;
+					link)
+						opt_link="true"
+						;;
+					union|bind)
+						;;
+					*)
+						log_warning_msg "Skipping custom mount with unkown option: ${opt}"
+						continue 2
+						;;
+				esac
+			done
+
+			source="${dir}"
+			if [ -n "${opt_source}" ]
+			then
+				if echo ${opt_source} | grep -q -e "^/" -e "^\(.*/\)\?\.\.\?\(/.*\)\?$" && [ "${opt_source}" != "." ]
+				then
+					log_warning_msg "Skipping unsafe custom mount with option source=${opt_source}: must be either \".\" (the media root) or a relative path w.r.t. the media root that contains neither comas, nor the special \".\" and \"..\" path components"
+					continue
+				else
+					source="${opt_source}"
+				fi
+			fi
+
+			full_source="$(trim_path ${backing}/${source})"
+			full_dest="$(trim_path ${rootmnt}/${dir})"
+			if [ -n "${opt_link}" ]
+			then
+				echo "${device} ${full_source} ${full_dest} ${options}" >> ${links}
+			else
+				echo "${device} ${full_source} ${full_dest} ${options}" >> ${bindings}
+			fi
+		done < ${include_list}
+	done
+
+	# We sort the list according to destination so we're sure that
+	# we won't hide a previous mount. We also ignore duplicate
+	# destinations in a more or less arbitrary way.
+	[ -e "${bindings}" ] && sort -k3 -sbu ${bindings} >> ${custom_mounts} && rm ${bindings}
+
+	# After all mounts are considered we add symlinks so they
+	# won't be hidden by some mount.
+	[ -e "${links}" ] && cat ${links} >> ${custom_mounts} && rm ${links}
+
+	# We need to make sure that no two custom mounts have the same sources
+	# or are nested; if that is the case, too much weird stuff can happen.
+	local prev_source prev_dest
+	prev_source="impossible source" # first iteration must not match
+	prev_dest=""
+	# This sort will ensure that a source /a comes right before a source
+	# /a/b so we only need to look at the previous source
+	sort -k2 -b ${custom_mounts} |
+	while read device source dest options
+	do
+		if echo ${source} | grep -qe "^${prev_source}\(/.*\)\?$"
+		then
+			panic "Two persistence mounts have the same or nested sources: ${source} on ${dest}, and ${prev_source} on ${prev_dest}"
+		fi
+		prev_source=${source}
+		prev_dest=${dest}
+	done
+}
+
+activate_custom_mounts ()
+{
+	local custom_mounts used_devices
+	custom_mounts="${1}" # the ouput from get_custom_mounts()
+	used_devices=""
+
+	while read device source dest options # < ${custom_mounts}
+	do
+		local opt_bind opt_link opt_union
+		opt_bind="true"
+		opt_link=""
+		opt_union=""
+		for opt in $(echo ${options} | tr ',' ' ');
+		do
+			case "${opt}" in
+				bind)
+					opt_bind="true"
+					unset opt_link opt_union
+					;;
+				link)
+					opt_link="true"
+					unset opt_bind opt_union
+					;;
+				union)
+					opt_union="true"
+					unset opt_bind opt_link
+					;;
+			esac
+		done
+
+		if [ -n "$(what_is_mounted_on "${dest}")" ]
+		then
+			if [ "${dest}" = "${rootmnt}" ]
+			then
+				umount "${dest}"
+			else
+				log_warning_msg "Skipping custom mount ${dest}: $(what_is_mounted_on "${dest}") is already mounted there"
+				continue
+			fi
+		fi
+
+		if [ ! -d "${dest}" ]
+		then
+			# create the destination and delete existing files in
+			# its path that are in the way
+			path="/"
+			for dir in $(echo ${dest} | sed -e 's|/\+| |g')
+			do
+				path=$(trim_path ${path}/${dir})
+				if [ -f ${path} ]
+				then
+					rm -f ${path}
+				fi
+				if [ ! -e ${path} ]
+				then
+					mkdir -p ${path}
+					if echo ${path} | grep -qe "^${rootmnt}/*home/[^/]\+"
+					then
+						# if ${dest} is in /home try fixing proper ownership by assuming that the intended user is the first, which is usually the case
+						# FIXME: this should really be handled by live-config since we don't know for sure which uid a certain user has until then
+						chown 1000:1000 ${path}
+					fi
+				fi
+			done
+		fi
+
+		# if ${source} doesn't exist on our persistence media
+		# we bootstrap it with $dest from the live filesystem.
+		# this both makes sense and is critical if we're
+		# dealing with /etc or other system dir.
+		if [ ! -d "${source}" ]
+		then
+			if [ -n "${PERSISTENCE_READONLY}" ]
+			then
+				continue
+			elif [ -n "${opt_union}" ] || [ -n "${opt_link}" ]
+			then
+				# unions and don't need to be bootstrapped
+				# link dirs can't be bootstrapped in a sensible way
+				mkdir -p "${source}"
+				chown_ref "${dest}" "${source}"
+				chmod_ref "${dest}" "${source}"
+			elif [ -n "${opt_bind}" ]
+			then
+				# ensure that $dest is not copied *into* $source
+				mkdir -p "$(dirname ${source})"
+				cp -a "${dest}" "${source}"
+			fi
+		fi
+
+		# XXX: If CONFIG_AUFS_ROBR is added to the Debian kernel we can
+		# ignore the loop below and set rootfs_dest_backing=$dest
+		local rootfs_dest_backing
+		rootfs_dest_backing=""
+		if [ -n "${opt_link}" ] || [ -n "${opt_union}" ]
+		then
+			for d in /live/rootfs/*
+			do
+				if [ -n "${rootmnt}" ]
+				then
+					fs="${d}/$(echo ${dest} | sed -e "s|${rootmnt}||")"
+				else
+					fs="${d}/${dest}"
+				fi
+				if [ -d "${fs}" ]
+				then
+					rootfs_dest_backing="${rootfs_dest_backing} ${fs}"
+				fi
+			done
+		fi
+
+		local cow_dir links_source
+		if [ -n "${opt_link}" ] && [ -z "${PERSISTENCE_READONLY}" ]
+		then
+			link_files ${source} ${dest} "s|^/live/|/lib/live/mount/|"
+		elif [ -n "${opt_link}" ] && [ -n "${PERSISTENCE_READONLY}" ]
+		then
+			mkdir -p ${rootmnt}/lib/live/mount/persistence
+			links_source=$(mktemp -d ${rootmnt}/lib/live/mount/persistence/links-source-XXXXXX)
+			chown_ref ${source} ${links_source}
+			chmod_ref ${source} ${links_source}
+			# We put the cow dir in the below strange place to
+			# make it absolutely certain that the link source
+			# has its own directory and isn't nested with some
+			# other custom mount (if so that mount's files would
+			# be linked, causing breakage.
+			cow_dir="/live/overlay/lib/live/mount/persistence/$(basename ${links_source})"
+			mkdir -p ${cow_dir}
+			chown_ref "${source}" "${cow_dir}"
+			chmod_ref "${source}" "${cow_dir}"
+			do_union ${links_source} ${cow_dir} ${source} ${rootfs_dest_backing}
+			link_files ${links_source} ${dest} "s|^${rootmnt}||"
+		elif [ -n "${opt_union}" ] && [ -z "${PERSISTENCE_READONLY}" ]
+		then
+			do_union ${dest} ${source} ${rootfs_dest_backing}
+		elif [ -n "${opt_bind}" ] && [ -z "${PERSISTENCE_READONLY}" ]
+		then
+			mount --bind "${source}" "${dest}"
+		elif [ -n "${opt_bind}" -o -n "${opt_union}" ] && [ -n "${PERSISTENCE_READONLY}" ]
+		then
+			# bind-mount and union mount are handled the same
+			# in read-only mode, but note that rootfs_dest_backing
+			# is non-empty (and necessary) only for unions
+			cow_dir="/live/overlay/${dest}"
+			if [ -e "${cow_dir}" ] && [ -z "${opt_link}" ]
+			then
+				# If an earlier custom mount has files here
+				# it will "block" the current mount's files
+				# which is undesirable
+				rm -rf "${cow_dir}"
+			fi
+			mkdir -p ${cow_dir}
+			chown_ref "${source}" "${cow_dir}"
+			chmod_ref "${source}" "${cow_dir}"
+			do_union ${dest} ${cow_dir} ${source} ${rootfs_dest_backing}
+		fi
+
+		PERSISTENCE_IS_ON="1"
+		export PERSISTENCE_IS_ON
+
+		if echo ${used_devices} | grep -qve "^\(.* \)\?${device}\( .*\)\?$"
+		then
+			used_devices="${used_devices} ${device}"
+		fi
+	done < ${custom_mounts}
+
+	echo ${used_devices}
+}
+
+is_mountpoint ()
+{
+	directory="$1"
+
+	[ $(stat -fc%d:%D "${directory}") != $(stat -fc%d:%D "${directory}/..") ]
+}