Merge branch 'debian'
[live-boot-grml.git] / scripts / live-helpers
index 70c7f34..3109356 100644 (file)
@@ -1,4 +1,4 @@
-# live-initramfs helper functions, used by live-initramfs on boot and by live-snapshot
+# live-boot helper functions, used by live-boot on boot and by live-snapshot
 
 if [ ! -x "/bin/fstype" ]
 then
@@ -6,10 +6,19 @@ then
        export PATH="${PATH}:/usr/lib/klibc/bin"
 fi
 
+# handle upgrade path from old udev (using udevinfo) to
+# recent versions of udev (using udevadm info)
+if [ -x /sbin/udevadm ]
+then
+       udevinfo='/sbin/udevadm info'
+else
+       udevinfo='udevinfo'
+fi
+
 sys2dev ()
 {
        sysdev=${1#/sys}
-       echo "/dev/$(udevinfo -q name -p ${sysdev} 2>/dev/null|| echo ${sysdev##*/})"
+       echo "/dev/$($udevinfo -q name -p ${sysdev} 2>/dev/null|| echo ${sysdev##*/})"
 }
 
 subdevices ()
@@ -17,7 +26,7 @@ subdevices ()
        sysblock=${1}
        r=""
 
-       for dev in "${sysblock}" "${sysblock}"/*
+       for dev in "${sysblock}"/* "${sysblock}"
        do
                if [ -e "${dev}/dev" ]
                then
@@ -28,6 +37,38 @@ subdevices ()
        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 "${sysblock}")
+
+               if echo "${black_listed_devices}" | grep -qe "\<${fulldevname}\>" || \
+                       [ -n "${white_listed_devices}" ] && \
+                       echo "${white_listed_devices}" | grep -qve "\<${fulldevname}\>"
+               then
+                       # skip this device entirely
+                       continue
+               fi
+
+               for dev in $(subdevices "${sysblock}")
+               do
+                       devname=$(sys2dev "${dev}")
+
+                       if echo "${black_listed_devices}" | grep -qe "\<${devname}\>"
+                       then
+                               # skip this subdevice
+                               continue
+                       else
+                               echo "${devname}"
+                       fi
+               done
+       done
+}
+
 is_supported_fs ()
 {
        fstype="${1}"
@@ -67,25 +108,7 @@ is_supported_fs ()
 
 get_fstype ()
 {
-       local FSTYPE
-       local FSSIZE
-
-       # fstype misreports LUKS devices
-       if is_luks "${1}"
-       then
-           /lib/udev/vol_id -t ${1} 2>/dev/null
-           return
-       fi
-
-       eval $(fstype < ${1})
-
-       if [ "${FSTYPE}" != "unknown" ]
-       then
-               echo ${FSTYPE}
-               return 0
-       fi
-
-       /lib/udev/vol_id -t ${1} 2>/dev/null
+       /sbin/blkid -s TYPE -o value $1 2>/dev/null
 }
 
 where_is_mounted ()
@@ -95,7 +118,7 @@ where_is_mounted ()
        if grep -q "^${device} " /proc/mounts
        then
                # return the first found
-               grep "^${device} " /proc/mounts | cut -f2 -d ' '
+               grep -m1 "^${device} " /proc/mounts | cut -f2 -d ' '
        fi
 }
 
@@ -146,7 +169,7 @@ fs_size ()
                        mountp="/mnt/tmp_fs_size"
 
                        mkdir -p "${mountp}"
-                       mount -n -t $(get_fstype "${dev}") -o ro "${dev}" "${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
@@ -163,7 +186,7 @@ fs_size ()
 
        if [ -n "${doumount}" ]
        then
-               umount "${mountp}"
+               umount "${mountp}" || log_warning_msg "cannot umount ${mountp}"
                rmdir "${mountp}"
        fi
 
@@ -188,16 +211,13 @@ setup_loop ()
        local encryption=${5}
        local readonly=${6}
 
-       modprobe -q -b "${module}"
+       # the output of setup_loop is evaluated in other functions,
+       # modprobe leaks kernel options like "libata.dma=0"
+       # as "options libata dma=0" on stdout, causing serious
+       # problems therefor, so instead always avoid output to stdout
+       modprobe -q -b "${module}" 1>/dev/null
 
-       if [ -x /sbin/udevadm ]
-       then
-               # lenny
-               udevadm settle
-       else
-               # etch
-               udevsettle
-       fi
+       udevadm settle
 
        for loopdev in ${pattern}
        do
@@ -206,7 +226,7 @@ setup_loop ()
                        dev=$(sys2dev "${loopdev}")
                        options=''
 
-                       if [ -n ${readonly} ]
+                       if [ -n "${readonly}" ]
                        then
                                if losetup --help 2>&1 | grep -q -- "-r\b"
                                then
@@ -214,7 +234,7 @@ setup_loop ()
                                fi
                        fi
 
-                       if [ 0 -lt "${offset}" ]
+                       if [ -n "${offset}" ] && [ 0 -lt "${offset}" ]
                        then
                                options="${options} -o ${offset}"
                        fi
@@ -269,87 +289,170 @@ try_mount ()
        dev="${1}"
        mountp="${2}"
        opts="${3}"
+       fstype="${4}"
 
        old_mountp="$(where_is_mounted ${dev})"
 
        if [ -n "${old_mountp}" ]
        then
-               mount -n -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
-               mount -n -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
+               if [ "${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
-               mount -n -t $(get_fstype "${dev}") -o "${opts}" "${dev}" "${mountp}" || panic "Cannot mount ${dev} on ${mountp}"
+               if [ -z "${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}" > live-boot.log && return 0 )
        fi
 }
 
-find_cow_device ()
+open_luks_device ()
 {
-       pers_label="${1}"
-       cow_backing="/${pers_label}-backing"
+       dev="${1}"
+       name="$(basename ${dev})"
+       opts="--key-file=-"
+       if [ -n "${PERSISTENT_READONLY}" ]
+       then
+               opts="${opts} --readonly"
+       fi
 
-       for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
+       load_keymap
+
+       while true
        do
-               for dev in $(subdevices "${sysblock}")
-               do
-                       devname=$(sys2dev "${dev}")
+               /lib/cryptsetup/askpass "Enter passphrase for ${dev}: " | \
+                       /sbin/cryptsetup -T 1 luksOpen ${dev} ${name} ${opts}
 
-                       if [ "$(/lib/udev/vol_id -l ${devname} 2>/dev/null)" = "${pers_label}" ]
-                       then
-                               echo "${devname}"
-                               return
-                       fi
+               if [ 0 -eq ${?} ]
+               then
+                       luks_device="/dev/mapper/${name}"
+                       echo ${luks_device}
+                       return 0
+               fi
 
-                       case "$(get_fstype ${devname})" in
-                               vfat|ext2|ext3|jffs2)
-                                       mkdir -p "${cow_backing}"
-                                       try_mount "${devname}" "${cow_backing}" "rw"
+               echo >&6
+               echo -n "There was an error decrypting ${dev} ... Retry? [Y/n] " >&6
+               read answer
 
-                                       if [ -f "${cow_backing}/${pers_label}" ]
-                                       then
-                                               echo $(setup_loop "${cow_backing}/${pers_label}" "loop" "/sys/block/loop*")
-                                               return 0
-                                       else
-                                               umount ${cow_backing}
-                                       fi
-                                       ;;
-                               *)
-                                       ;;
-                       esac
-               done
+               if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
+               then
+                       return 2
+               fi
        done
 }
 
-find_files ()
+find_persistent_media ()
 {
-       # return the first of ${filenames} found on vfat and ext2/ext3 devices
-       # FIXME: merge with above function
-
-       filenames="${1}"
-       snap_backing="/snap-backing"
-
-       for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
+       # 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
-               for dev in $(subdevices "${sysblock}")
-               do
-                       devname=$(sys2dev "${dev}")
-                       devfstype="$(get_fstype ${devname})"
+               luks_device=""
 
-                       if is_supported_fs ${devfstype}
+               # Checking for a luks device
+               if echo ${PERSISTENT_ENCRYPTION} | grep -qe "\<luks\>" && \
+                  /sbin/cryptsetup isLuks ${dev}
+               then
+                       if luks_device=$(open_luks_device "${dev}")
                        then
-                               mkdir -p "${snap_backing}"
-                               try_mount "${devname}" "${snap_backing}" "ro"
+                               dev="${luks_device}"
+                       else
+                               # skip $dev since we failed/chose not to open it
+                               continue
+                       fi
+               elif echo ${PERSISTENT_ENCRYPTION} | grep -qve "\<none\>"
+               then
+                       # skip $dev since we don't allow unencrypted storage
+                       continue
+               fi
 
-                               for filename in ${filenames}
-                                       do
-                                       if [ -f "${snap_backing}/${filename}" ]
+               if echo ${PERSISTENT_STORAGE} | grep -qe "\<filesystem\>"
+               then
+                       for label in ${overlays} ${snapshots}
+                       do
+                               if [ "$(/sbin/blkid -s LABEL -o value $dev 2>/dev/null)" = "${label}" ]
+                               then
+                                       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
+                       done
+               fi
+
+               if echo ${PERSISTENT_STORAGE} | grep -qe "\<file\>"
+               then
+                       devfstype="$(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 label in ${overlays}
+                               do
+                                       path=${backing}/${PERSISTENT_PATH}${label}
+                                       if [ -f "${path}" ]
                                        then
-                                               echo "${devname} ${snap_backing} ${filename}"
-                                               return 0
+                                               overlays=$(echo ${overlays} | sed -e "s|\<${label}\>||")
+                                               overlay_on_dev="yes"
+                                               echo "${label}=$(setup_loop "${path}" "loop" "/sys/block/loop*")"
                                        fi
                                done
 
-                               umount ${snap_backing}
+                               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
-               done
+                       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
+               fi
        done
 }
 
@@ -383,3 +486,73 @@ is_luks()
     fi
 
 }
+
+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="yes"
+                       else
+                               if readlink ${sysblock} | grep -q usb
+                               then
+                                       dev_ok="yes"
+                               fi
+                       fi
+               fi
+
+               if [ "${dev_ok}" = "yes" ]
+               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}"
+}