fi
}
-find_snap ()
-{
- # Look for ${snap_label}.* in block devices
- snap_label="${1}"
- black_listed_devices="${2}"
- white_listed_devices="${3}"
-
- if echo ${PERSISTENT_STORAGE} | grep -qw file
- then
- # search for image files
- snapdata=$(find_files "${PERSISTENT_PATH}${snap_label}.squashfs ${PERSISTENT_PATH}${snap_label}.cpio.gz ${PERSISTENT_PATH}${snap_label}.ext2 ${PERSISTENT_PATH}${snap_label}.ext3 ${PERSISTENT_PATH}${snap_label}.ext4 ${PERSISTENT_PATH}${snap_label}.jffs2" "${black_listed_devices}" "${white_listed_devices}")
- fi
-
- if echo ${PERSISTENT_STORAGE} | grep -qw filesystem && [ -z "${snapdata}" ]
- then
- snapdata=$(find_cow_device "${snap_label}" "${black_listed_devices}" "${white_listed_devices}")
- fi
- echo "${snapdata}"
-}
-
try_snap ()
{
# copy the contents of previously found snapshot to ${snap_mount}
if echo ${PERSISTENT_METHOD} | grep -qw overlay
then
- # search for label and files (this could be hugely optimized)
- cowprobe=$(find_cow_device "${root_persistence}" "${blacklistdev}" "${whitelistdev}")
- if [ -b "${cowprobe}" ]
- then
- # Blacklist /cow device, to avoid inconsistent setups for overlapping snapshots
- # makes sense to have both persistence for /cow and /home mounted, maybe also with
- # snapshots to be sure to really store some e.g key config files,
- # but not on the same media
- blacklistdev="${cowprobe}"
- PERSISTENCE_IS_ON="1"
- export PERSISTENCE_IS_ON
- fi
- # homecow just mount something on /home, this should be generalized some way
- homecow=$(find_cow_device "${home_persistence}" "${blacklistdev}" "${whitelistdev}")
- if [ -b "${homecow}" ]
- then
- PERSISTENCE_IS_ON="1"
- export PERSISTENCE_IS_ON
- fi
+ overlays="${root_persistence} ${home_persistence}"
fi
if echo ${PERSISTENT_METHOD} | grep -qw snapshot
then
- root_snapdata=$(find_snap "${root_snapshot_label}" "${blacklistdev}" "${whitelistdev}")
- # This second type should be removed when snapshot will get smarter,
- # hence when "/etc/live-snapshot*list" will be supported also by
- # ext2|ext3|ext4|jffs2 snapshot types.
- home_snapdata=$(find_snap "${home_snapshot_label}" "${blacklistdev}" "${whitelistdev}")
+ snapshots="${root_snapshot_label} ${home_snapshot_label}"
+ fi
+
+
+ for media in $(find_persistent_media "${overlays}" "${snapshots}" "${blacklistdev}" "${whitelistdev}")
+ do
+ media="$(echo ${media} | tr ":" " ")"
+ case ${media} in
+ ${root_persistence}=*)
+ cowprobe="${media#*=}"
+ ;;
+ ${home_persistence}=*)
+ homecow="${media#*=}"
+ ;;
+ ${root_snapshot_label}=*)
+ root_snapdata="${media#*=}"
+ ;;
+ ${home_snapshot_label}=*)
+ # This second type should be removed when snapshot will get smarter,
+ # hence when "/etc/live-snapshot*list" will be supported also by
+ # ext2|ext3|ext4|jffs2 snapshot types.
+ home_snapdata="${media#*=}"
+ ;;
+ *)
+ ;;
+ esac
+ done
+
+ if [ -b "${cowprobe}" ] || [ -b "${homecow}" ]
+ then
+ PERSISTENCE_IS_ON="1"
+ export PERSISTENCE_IS_ON
fi
if [ -b "${cowprobe}" ]
fsck -y ${cowdevice}
fi
else
- log_warning_msg "Unable to find the persistent medium"
cowdevice="tmpfs"
cow_fstype="tmpfs"
cow_mountopt="rw,noatime,mode=755"
fi
}
-find_cow_device ()
+find_persistent_media ()
{
- # Returns a device containing a partition labeled "${pers_label}" or containing a file named the same way
- # in the latter case the partition containing the file is left mounted
- # if is not in black_listed_devices.
- # Additionally, if the white_listed_devices list is non-empty, the
- # parent block device of the returned device must be part of this list.
- pers_label="${1}"
- cow_backing="/${pers_label}-backing"
- black_listed_devices="${2}"
- white_listed_devices="${3}"
-
- if [ -z "${PERSISTENT_PATH}" ]
- then
- pers_fpath=${cow_backing}/${pers_label}
- else
- pers_fpath=${cow_backing}/${PERSISTENT_PATH}/${pers_label}
- fi
+ # Scans devices for overlays and snapshots, and returns a whitespace
+ # separated list of how to use them. Only overlays with a partition
+ # label or file name in ${overlays} are returned, and ditto for
+ # snapshots with labels in ${snapshots}.
+ #
+ # When scanning a LUKS device, the user will be asked to enter the
+ # passphrase; on failure to enter it, or if no persistent partitions
+ # or files were found, the LUKS device is closed.
+ #
+ # For a snapshot file the return value is ${label}=${snapdata}", where
+ # ${snapdata} is the parameter used for try_snap().
+ #
+ # For all other cases (overlay/snapshot partition and overlay file) the
+ # return value is "${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
+ # ${white_list_devices} is non-empty, only devices in it will be
+ # scanned.
+
+ overlays="${1}"
+ snapshots="${2}"
+ black_listed_devices="${3}"
+ white_listed_devices="${4}"
for dev in $(storage_devices "${black_listed_devices}" "${white_listed_devices}")
do
+ luks_device=""
+
# Checking for a luks device
if [ "${PERSISTENT_ENCRYPTION}" = "luks" ] && [ -e /sbin/cryptsetup ]
then
continue
fi
+ if [ ! -x /lib/cryptsetup/askpass ] || [ ! -x /sbin/cryptsetup ]
+ then
+ log_warning_msg "cryptsetup in unavailable"
+ continue
+ fi
+
if ! /sbin/cryptsetup isLuks ${dev}
then
- # we only look for encrypted subdevices
+ # skip device since we strictly want luks devices
continue
fi
+ load_keymap
+
while true
do
- load_keymap
+ /lib/cryptsetup/askpass "Enter passphrase for ${dev}: " | /sbin/cryptsetup -T 1 luksOpen ${dev} $(basename ${dev}) --key-file=-
- /lib/cryptsetup/askpass "Enter passphrase for ${pers_label} on ${dev}: " | /sbin/cryptsetup -T 1 luksOpen ${dev} $(basename ${dev}) --key-file=-
- error=${?}
-
- dev="/dev/mapper/$(basename ${dev})"
-
- if [ 0 -eq ${error} ]
+ if [ 0 -eq ${?} ]
then
- unset error
+ luks_device="/dev/mapper/$(basename ${dev})"
+ dev="${luks_device}"
break
fi
if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
then
- unset answer
- # skip to next subdevice
- continue 2
+ break
fi
done
fi
- if echo ${PERSISTENT_STORAGE} | grep -qw filesystem && [ "$(/sbin/blkid -s LABEL -o value $dev 2>/dev/null)" = "${pers_label}" ]
- then
- echo "${dev}"
- return 0
- fi
-
- if ! echo ${PERSISTENT_STORAGE} | grep -qw file
- then
- # do not mount the device to find for image files
- # just skip this
- continue
- fi
-
- devfstype="$(get_fstype ${dev})"
-
- if is_supported_fs ${devfstype}
+ if echo ${PERSISTENT_STORAGE} | grep -qw filesystem
then
- mkdir -p "${cow_backing}"
- if try_mount "${dev}" "${cow_backing}" "rw"
- then
- if [ -f "${pers_fpath}" ]
+ for label in ${overlays} ${snapshots}
+ do
+ if [ "$(/sbin/blkid -s LABEL -o value $dev 2>/dev/null)" = "${label}" ]
then
- echo $(setup_loop "${pers_fpath}" "loop" "/sys/block/loop*")
- return 0
- else
- umount ${cow_backing} > /dev/null 2>&1 || true
+ overlays=$(echo ${overlays} | sed -e "s|\<${label}\>||")
+ snapshots=$(echo ${snapshots} | sed -e "s|\<${label}\>||")
+ echo "${label}=${dev}"
+ # skip to the next device
+ continue 2
fi
- fi
+ done
fi
- done
- return 1
-}
-
-find_files ()
-{
- # return the a string composed by device name, mountpoint an the first of ${filenames} found on a supported partition
- # if is not in black_listed_devices.
- # Additionally, if the white_listed_devices list is non-empty, the
- # parent block device of the returned device must be part of this list.
- # FIXME: merge with above function
-
- filenames="${1}"
- snap_backing="/snap-backing"
- black_listed_devices="${2}"
- white_listed_devices="${3}"
- for dev in $(storage_devices "${black_listed_devices}" "${white_listed_devices}")
- do
- devfstype="$(get_fstype ${dev})"
-
- if is_supported_fs ${devfstype}
+ if echo ${PERSISTENT_STORAGE} | grep -qw file
then
- mkdir -p "${snap_backing}"
-
- if try_mount "${dev}" "${snap_backing}" "ro" "${devfstype}"
+ devfstype="$(get_fstype ${dev})"
+ overlay_on_dev=""
+ snapshot_on_dev=""
+ backing="/$(basename ${dev})-backing"
+ mkdir -p "${backing}"
+ if is_supported_fs ${devfstype} && try_mount "${dev}" "${backing}" "rw" "${devfstype}"
then
- for filename in ${filenames}
+ for label in ${overlays}
do
- if [ -f "${snap_backing}/${filename}" ]
+ path=${backing}/${PERSISTENT_PATH}${label}
+ if [ -f "${path}" ]
then
- echo "${dev} ${snap_backing} ${filename}"
- umount ${snap_backing}
- return 0
+ overlays=$(echo ${overlays} | sed -e "s|\<${label}\>||")
+ overlay_on_dev="yes"
+ echo "${label}=$(setup_loop "${path}" "loop" "/sys/block/loop*")"
fi
done
+
+ for label in ${snapshots}
+ do
+ for ext in squashfs cpio.gz ext2 ext3 ext4 jffs2
+ do
+ path="${PERSISTENT_PATH}${label}.${ext}"
+ if [ -f "${backing}/${path}" ]
+ then
+ snapshots=$(echo ${snapshots} | sed -e "s|\<${label}\>||")
+ snapshot_on_dev="yes"
+ echo "${label}=${dev}:${backing}:${path}"
+ fi
+ done
+ done
+ fi
+ if [ -z "${overlay_on_dev}" ]
+ then
+ umount ${backing} > /dev/null 2>&1 || true
+ if [ -z "${snapshot_on_dev}" ] && [ -n "${luks_device}" ] && /sbin/cryptsetup status "${luks_device}" 1> /dev/null
+ then
+ /sbin/cryptsetup luksClose "${luks_device}"
+ fi
fi
- umount ${snap_backing}
fi
done
}
projects / live-boot-grml.git / commitdiff