scripts/live-helpers

   1 #!/bin/sh
   2 # live-initramfs helper functions, used by live-initramfs on boot and by live-snapshot
   3
   4 if [ ! -x "/bin/fstype" ]
   5 then
   6         # klibc not in path -> not in initramfs
   7         export PATH="${PATH}:/usr/lib/klibc/bin"
   8 fi
   9
  10 sys2dev ()
  11 {
  12         sysdev=${1#/sys}
  13         echo "/dev/$(udevinfo -q name -p ${sysdev} 2>/dev/null|| echo ${sysdev##*/})"
  14 }
  15
  16 subdevices ()
  17 {
  18         sysblock=${1}
  19         r=""
  20
  21         for dev in "${sysblock}" "${sysblock}"/*
  22         do
  23                 if [ -e "${dev}/dev" ]
  24                 then
  25                         r="${r} ${dev}"
  26                 fi
  27         done
  28
  29         echo ${r}
  30 }
  31
  32 is_supported_fs ()
  33 {
  34         # FIXME: do something better like the scan of supported filesystems
  35         fstype="${1}"
  36
  37         case ${fstype} in
  38                 vfat|iso9660|udf|ext2|ext3|ntfs|jffs2)
  39                 return 0
  40                 ;;
  41         esac
  42
  43         return 1
  44 }
  45
  46 get_fstype ()
  47 {
  48         local FSTYPE
  49         local FSSIZE
  50
  51         # fstype misreports LUKS devices
  52         if is_luks "${1}"
  53         then
  54             /lib/udev/vol_id -t ${1} 2>/dev/null
  55             return
  56         fi
  57
  58         eval $(fstype < ${1})
  59
  60         if [ "${FSTYPE}" != "unknown" ]
  61         then
  62                 echo ${FSTYPE}
  63                 return 0
  64         fi
  65
  66         /lib/udev/vol_id -t ${1} 2>/dev/null
  67 }
  68
  69 where_is_mounted ()
  70 {
  71         device=${1}
  72
  73         if grep -q "^${device} " /proc/mounts
  74         then
  75                 grep "^${device} " /proc/mounts | read d mountpoint rest
  76                 echo ${mountpoint}
  77                 return 0
  78         fi
  79
  80         return 1
  81 }
  82
  83 lastline ()
  84 {
  85         while read lines
  86         do
  87                 line=${lines}
  88         done
  89
  90         echo "${line}"
  91 }
  92
  93 base_path ()
  94 {
  95         testpath="${1}"
  96         mounts="$(awk '{print $2}' /proc/mounts)"
  97         testpath="$(busybox realpath ${testpath})"
  98
  99         while true
 100         do
 101                 if echo "${mounts}" | grep -qs "^${testpath}"
 102                 then
 103                         set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
 104                         echo ${1}
 105                         break
 106                 else
 107                         testpath=$(dirname $testpath)
 108                 fi
 109         done
 110 }
 111
 112 fs_size ()
 113 {
 114         # Returns used/free fs kbytes + 5% more
 115         # You could pass a block device as ${1} or the mount point as ${2}
 116
 117         dev="${1}"
 118         mountp="${2}"
 119         used="${3}"
 120
 121         if [ -z "${mountp}" ]
 122         then
 123                 mountp=$(where_is_mounted "${dev}")
 124
 125                 if [ "${?}" -gt 0 ]
 126                 then
 127                         mountp="/mnt/tmp_fs_size"
 128
 129                         mkdir -p "${mountp}"
 130                         mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}"
 131
 132                         doumount=1
 133                 fi
 134         fi
 135
 136         if [ "${used}" = "used" ]
 137         then
 138                 size=$(du -ks ${mountp} | cut -f1)
 139                 size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
 140         else
 141                 # free space
 142                 size="$(df -k | grep -s ${mountp} | awk '{print $4}')"
 143         fi
 144
 145         if [ -n "${doumount}" ]
 146         then
 147                 umount "${mountp}"
 148                 rmdir "${mountp}"
 149         fi
 150
 151         echo "${size}"
 152 }
 153
 154 load_keymap ()
 155 {
 156         # Load custom keymap
 157         if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
 158         then
 159                 loadkeys /etc/boottime.kmap.gz
 160         fi
 161 }
 162
 163 setup_loop ()
 164 {
 165         local fspath=${1}
 166         local module=${2}
 167         local pattern=${3}
 168         local offset=${4}
 169         local encryption=${5}
 170         local readonly=${6}
 171
 172         modprobe -q -b "${module}"
 173         udevsettle
 174
 175         for loopdev in ${pattern}
 176         do
 177                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 178                 then
 179                         dev=$(sys2dev "${loopdev}")
 180                         options=''
 181
 182                         if [ -n ${readonly} ]
 183                         then
 184                                 if /sbin/losetup --help 2>&1 | grep -q -- "-r\b"
 185                                 then
 186                                         options="${options} -r"
 187                                 fi
 188                         fi
 189
 190                         if [ 0 -lt "${offset}" ]
 191                         then
 192                                 options="${options} -o ${offset}"
 193                         fi
 194
 195                         if [ -z "${encryption}" ]
 196                         then
 197                                 losetup ${options} "${dev}" "${fspath}"
 198                         else
 199                                 # Loop AES encryption
 200                                 while true
 201                                 do
 202                                         load_keymap
 203
 204                                         echo -n "Enter passphrase for root filesystem: " >&6
 205                                         read -s passphrase
 206                                         echo "${passphrase}" > /tmp/passphrase
 207                                         unset passphrase
 208                                         exec 9</tmp/passphrase
 209                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 210                                         error=${?}
 211                                         exec 9<&-
 212                                         rm -f /tmp/passphrase
 213
 214                                         if [ 0 -eq ${error} ]
 215                                         then
 216                                                 unset error
 217                                                 break
 218                                         fi
 219
 220                                         echo
 221                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 222                                         read answer
 223
 224                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 225                                         then
 226                                                 unset answer
 227                                                 break
 228                                         fi
 229                                 done
 230                         fi
 231
 232                         echo "${dev}"
 233                         return 0
 234                 fi
 235         done
 236
 237         panic "No loop devices available"
 238 }
 239
 240 try_mount ()
 241 {
 242         dev="${1}"
 243         mountp="${2}"
 244         opts="${3}"
 245
 246         if where_is_mounted ${dev} > /dev/null
 247         then
 248                 mount -o remount,"${opts}" ${dev} $(where_is_mounted ${dev}) || panic "Remounting failed"
 249                 mount -o bind $(where_is_mounted ${dev}) ${mountp} || panic "Cannot bind-mount"
 250         else
 251                 mount -t $(get_fstype "${dev}") -o "${opts}" "${dev}" "${mountp}" || panic "Cannot mount ${dev} on ${mountp}"
 252         fi
 253 }
 254
 255 find_cow_device ()
 256 {
 257         pers_label="${1}"
 258         cow_backing="/${pers_label}-backing"
 259
 260         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 261         do
 262                 for dev in $(subdevices "${sysblock}")
 263                 do
 264                         devname=$(sys2dev "${dev}")
 265
 266                         if [ "$(/lib/udev/vol_id -l ${devname} 2>/dev/null)" = "${pers_label}" ]
 267                         then
 268                                 echo "${devname}"
 269                                 return
 270                         fi
 271
 272                         case "$(get_fstype ${devname})" in
 273                                 vfat|ext2|ext3|jffs2)
 274                                         mkdir -p "${cow_backing}"
 275                                         try_mount "${devname}" "${cow_backing}" "rw"
 276
 277                                         if [ -f "${cow_backing}/${pers_label}" ]
 278                                         then
 279                                                 echo $(setup_loop "${cow_backing}/${pers_label}" "loop" "/sys/block/loop*")
 280                                                 return 0
 281                                         else
 282                                                 umount ${cow_backing}
 283                                         fi
 284                                         ;;
 285                                 *)
 286                                         ;;
 287                         esac
 288                 done
 289         done
 290 }
 291
 292 find_files ()
 293 {
 294         # return the first of ${filenames} found on vfat and ext2/ext3 devices
 295         # FIXME: merge with above function
 296
 297         filenames="${1}"
 298         snap_backing="/snap-backing"
 299
 300         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 301         do
 302                 for dev in $(subdevices "${sysblock}")
 303                 do
 304                         devname=$(sys2dev "${dev}")
 305                         devfstype="$(get_fstype ${devname})"
 306
 307                         if is_supported_fs ${devfstype}
 308                         then
 309                                 mkdir -p "${snap_backing}"
 310                                 try_mount "${devname}" "${snap_backing}" "ro"
 311
 312                                 for filename in ${filenames}
 313                                         do
 314                                         if [ -f "${snap_backing}/${filename}" ]
 315                                         then
 316                                                 echo "${devname} ${snap_backing} ${filename}"
 317                                                 return 0
 318                                         fi
 319                                 done
 320
 321                                 umount ${snap_backing}
 322                         fi
 323                 done
 324         done
 325 }
 326
 327 get_mac ()
 328 {
 329         mac=""
 330
 331         for adaptor in /sys/class/net/*
 332         do
 333                 status="$(cat ${adaptor}/iflink)"
 334
 335                 if [ "${status}" -eq 2 ]
 336                 then
 337                         mac="$(cat ${adaptor}/address)"
 338                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
 339                 fi
 340         done
 341
 342         echo ${mac}
 343 }
 344
 345 is_luks()
 346 {
 347     devname="${1}"
 348     if [ -x /sbin/cryptsetup ]
 349     then
 350         /sbin/cryptsetup isLuks "${devname}" 2>/dev/null || ret=${?}
 351         return ${ret}
 352     else
 353         return 1
 354     fi
 355
 356 }