Do not allow mutually exclusive custom mount options.
[live-boot-grml.git] / scripts / live-helpers
index be7cf76..7c4e0d7 100644 (file)
@@ -764,6 +764,22 @@ mount_persistent_media ()
        return 0
 }
 
+close_persistent_media () {
+       local device=${1}
+       local backing="$(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}"
@@ -832,15 +848,23 @@ probe_for_gpt_name ()
        local snapshots="${2}"
        local dev="${3}"
 
-       if ! is_gpt_device ${dev} || \
-          ( echo ${PERSISTENT_ENCRYPTION} | grep -qve "\<luks\>" && \
-            /sbin/cryptsetup isLuks ${dev} > /dev/null 2>&1 )
+       local gpt_dev="${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 ${gpt_dev}
        then
                return
        fi
+
+       local gpt_name=$(get_gpt_name ${gpt_dev})
        for label in ${overlays} ${snapshots}
        do
-               if [ "$(get_gpt_name ${dev})" = "${label}" ]
+               if [ "${gpt_name}" = "${label}" ]
                then
                        echo "${label}=${dev}"
                fi
@@ -936,18 +960,16 @@ find_persistent_media ()
        do
                local result=""
 
-               local real_dev=""
                local 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. do_custom_mounts() also depends on that any luks
+               # below. activate_custom_mounts() also depends on that any luks
                # device already has been opened.
                if echo ${PERSISTENT_ENCRYPTION} | grep -qe "\<luks\>" && \
-                  /sbin/cryptsetup isLuks ${dev} >/dev/null 2>&1
+                  is_luks_partition ${dev}
                then
                        if luks_device=$(open_luks_device "${dev}")
                        then
-                               real_dev="${dev}"
                                dev="${luks_device}"
                        else
                                # skip $dev since we failed/chose not to open it
@@ -962,15 +984,7 @@ find_persistent_media ()
                # Probe for matching GPT partition names or filesystem labels
                if echo ${PERSISTENT_STORAGE} | grep -qe "\<filesystem\>"
                then
-                       local gpt_dev="${dev}"
-                       if [ -n "${luks_device}" ]
-                       then
-                               # When we probe GPT partitions we need to look
-                               # at the real device, not the virtual, opened
-                               # luks device
-                               gpt_dev="${real_dev}"
-                       fi
-                       result=$(probe_for_gpt_name "${overlays}" "${snapshots}" ${gpt_dev})
+                       result=$(probe_for_gpt_name "${overlays}" "${snapshots}" ${dev})
                        if [ -n "${result}" ]
                        then
                                ret="${ret} ${result}"
@@ -998,7 +1012,7 @@ find_persistent_media ()
 
                # Close luks device if it isn't used
                if [ -z "${result}" ] && [ -n "${luks_device}" ] && \
-                  /sbin/cryptsetup status "${luks_device}" 1> /dev/null 2>&1
+                  is_active_luks_mapping "${luks_device}"
                then
                        /sbin/cryptsetup luksClose "${luks_device}"
                fi
@@ -1028,17 +1042,22 @@ get_mac ()
        echo ${mac}
 }
 
-is_luks()
+is_luks_partition ()
 {
-    devname="${1}"
-    if [ -x /sbin/cryptsetup ]
-    then
-       /sbin/cryptsetup isLuks "${devname}" 2>/dev/null || ret=${?}
-       return ${ret}
-    else
-       return 1
-    fi
+       device="${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 ()
@@ -1225,8 +1244,9 @@ get_custom_mounts ()
        # Side-effect: leaves $devices with live.persist mounted in ${rootmnt}/live/persistent
        # Side-effect: prints info to file $custom_mounts
 
-       local devices="${1}"
-       local custom_mounts="${2}" # print result to this file
+       local custom_mounts=${1}
+       shift
+       local devices=${@}
 
        local bindings="/tmp/bindings.list"
        local links="/tmp/links.list"
@@ -1240,7 +1260,6 @@ get_custom_mounts ()
                fi
 
                local device_name="$(basename ${device})"
-               local device_used=""
                local backing=$(mount_persistent_media ${device})
                if [ -z "${backing}" ]
                then
@@ -1250,12 +1269,6 @@ get_custom_mounts ()
                local include_list="${backing}/${persistence_list}"
                if [ ! -r "${include_list}" ]
                then
-                       umount "${backing}" >/dev/null 2>&1
-                       rmdir "${backing}" >/dev/null 2>&1
-                       if /sbin/cryptsetup status ${device_name} >/dev/null 2>&1
-                       then
-                               /sbin/cryptsetup luksClose "${device_name}"
-                       fi
                        continue
                fi
 
@@ -1272,19 +1285,20 @@ get_custom_mounts ()
                                continue
                        fi
 
-                       if echo ${dest} | grep -qe "^[^/]"
+                       if [ -z "${dest}" ]
                        then
-                               options="${dest}"
                                dest="${source}"
-                       elif [ -z "${dest}" ]
+                       fi
+
+                       if trim_path ${source} | grep -q -e "^[^/]" -e "^\(.*/\)\?\.\.\?\(/.*\)\?$"
                        then
-                               dest="${source}"
+                               log_warning_msg "Skipping unsafe custom mount with source ${source}: the source must be an absolute path w.r.t. the persistent media root and cannot contain \".\" or \"..\""
+                               continue
                        fi
 
-                       if echo ${dest} | grep -qe "^/\+$\|^/\+live\(/.*\)\?$"
+                       if trim_path ${dest} | grep -q -e "^[^/]" -e "^/$" -e "^/live\(/.*\)\?$" -e "^/\(.*/\)\?\.\.\?\(/.*\)\?$"
                        then
-                               # mounting on / or /live could cause trouble
-                               log_warning_msg "Skipping unsafe custom mount on ${dest}"
+                               log_warning_msg "Skipping unsafe custom mount with desination ${dest}: the destination must be an absolute path containing neither \".\" nor \"..\", and cannot be /live (or any sub-directory therein) or / (for the latter, use ${root_overlay_label}-type persistence instead)"
                                continue
                        fi
 
@@ -1300,51 +1314,34 @@ get_custom_mounts ()
                                esac
                        done
 
-                       # FIXME: handle case: we already have /a/b in
-                       # $bindings added from current $device, but
-                       # now we find /a -- /a should replace /a/b in
-                       # $bindings.
-
-                       # FIXME: handle case: we have /a in $bindings
-                       # from current $device, now we find /a/b, so
-                       # we skip /a/b
-
                        # ensure that no multiple-/ occur in paths
-                       local full_source="$(echo ${backing}/${source}/ | sed -e 's|/\+|/|g')"
-                       local full_dest="$(echo ${rootmnt}/${dest}/ | sed -e 's|/\+|/|g')"
-                       device_used="yes"
+                       local full_source="$(trim_path ${backing}/${source})"
+                       local full_dest="$(trim_path ${rootmnt}/${dest})"
                        if echo ${options} | grep -qe "\<linkfiles\>";
                        then
-                               echo "${full_source} ${full_dest} ${options}" >> ${links}
+                               echo "${device} ${full_source} ${full_dest} ${options}" >> ${links}
                        else
-                               echo "${full_source} ${full_dest} ${options}" >> ${bindings}
+                               echo "${device} ${full_source} ${full_dest} ${options}" >> ${bindings}
                        fi
                done < ${include_list}
-
-               if [ -z "${device_used}" ]
-               then
-                       # this device was not used for / earlier, or
-                       # custom mount point now, so it's useless
-                       umount "${backing}"
-                       rmdir "${backing}"
-               fi
        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 -k2 -sbu ${bindings} >> ${custom_mounts} && rm ${bindings}
+       [ -e "${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}" ] && sort -k2 -sbu ${links} >> ${custom_mounts} && rm ${links}
+       [ -e "${links}" ] && sort -k3 -sbu ${links} >> ${custom_mounts} && rm ${links}
 }
 
-do_custom_mounts ()
+activate_custom_mounts ()
 {
        local custom_mounts="${1}" # the ouput from get_custom_mounts()
+       local used_devices=""
 
-       while read source dest options # < ${custom_mounts}
+       while read device source dest options # < ${custom_mounts}
        do
                local opt_linkfiles=""
                local opt_union=""
@@ -1360,6 +1357,11 @@ do_custom_mounts ()
                        esac
                done
 
+               if [ -n "${opt_linkfiles}" ] && [ -n "${opt_union}" ]
+               then
+                       log_warning_msg "Skipping custom mount ${dest} with options ${options}: \"linkfiles\" and \"union\" are mutually exclusive options"
+               fi
+
                if [ -n "$(what_is_mounted_on "${dest}")" ]
                then
                        log_warning_msg "Skipping custom mount ${source} on ${dest}: $(what_is_mounted_on "${dest}") is already mounted there"
@@ -1377,7 +1379,7 @@ do_custom_mounts ()
                        # FIXME: this should really be handled by
                        # live-config since we don't know for sure
                        # which uid a certain user has until then
-                       if echo ${dest} | grep -qe "^${rootmnt}/*home/\+[^/]\+"
+                       if trim_path ${dest} | grep -qe "^${rootmnt}/*home/[^/]\+"
                        then
                                path="/"
                                for dir in $(echo ${dest} | sed -e 's|/\+| |g')
@@ -1401,13 +1403,16 @@ do_custom_mounts ()
                # dealing with /etc or other system dir.
                if [ ! -d "${source}" ]
                then
-                       if [ -n "${PERSISTENT_READONLY}" ] || [ -n "${opt_linkfiles}" ]
+                       if [ -n "${PERSISTENT_READONLY}" ]
                        then
                                continue
-                       elif [ -n "${opt_union}" ]
+                       elif [ -n "${opt_union}" ] || [ -n "${opt_linkfiles}" ]
                        then
-                               # union's don't need to be bootstrapped
+                               # unions and don't need to be bootstrapped
+                               # linkfiles dirs can't be bootstrapped in a sensible way
                                mkdir "${source}"
+                               chown --reference "${dest}" "${source}"
+                               chmod --reference "${dest}" "${source}"
                        else
                                # ensure that $dest is not copied *into* $source
                                mkdir -p "$(dirname ${source})"
@@ -1458,6 +1463,8 @@ do_custom_mounts ()
                                cow_dir="/live/cow/${dest}"
                        fi
                        mkdir -p ${cow_dir}
+                       chown --reference "${source}" "${cow_dir}"
+                       chmod --reference "${source}" "${cow_dir}"
                        do_union ${dest} ${cow_dir} ${source} ${rofs_dest_backing}
                fi
 
@@ -1468,7 +1475,14 @@ do_custom_mounts ()
 
                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}
 }
 
 fix_home_rw_compatibility ()
@@ -1490,6 +1504,6 @@ fix_home_rw_compatibility ()
        if [ ! -r "${include_list}" ]
        then
                echo "# home-rw backwards compatibility:
-. /home" > "${include_list}"
+/ /home" > "${include_list}"
        fi
 }