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 "^${device} " /proc/mounts
  74         then
  75                 # return the first found
  76                 grep "^${device} " /proc/mounts | cut -f2 -d ' '
  77         fi
  78 }
  79
  80 lastline ()
  81 {
  82         while read lines
  83         do
  84                 line=${lines}
  85         done
  86
  87         echo "${line}"
  88 }
  89
  90 base_path ()
  91 {
  92         testpath="${1}"
  93         mounts="$(awk '{print $2}' /proc/mounts)"
  94         testpath="$(busybox realpath ${testpath})"
  95
  96         while true
  97         do
  98                 if echo "${mounts}" | grep -qs "^${testpath}"
  99                 then
 100                         set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
 101                         echo ${1}
 102                         break
 103                 else
 104                         testpath=$(dirname $testpath)
 105                 fi
 106         done
 107 }
 108
 109 fs_size ()
 110 {
 111         # Returns used/free fs kbytes + 5% more
 112         # You could pass a block device as ${1} or the mount point as ${2}
 113
 114         dev="${1}"
 115         mountp="${2}"
 116         used="${3}"
 117
 118         if [ -z "${mountp}" ]
 119         then
 120                 mountp="$(where_is_mounted ${dev})"
 121
 122                 if [ -z "${mountp}" ]
 123                 then
 124                         mountp="/mnt/tmp_fs_size"
 125
 126                         mkdir -p "${mountp}"
 127                         mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}"
 128
 129                         doumount=1
 130                 fi
 131         fi
 132
 133         if [ "${used}" = "used" ]
 134         then
 135                 size=$(du -ks ${mountp} | cut -f1)
 136                 size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
 137         else
 138                 # free space
 139                 size="$(df -k | grep -s ${mountp} | awk '{print $4}')"
 140         fi
 141
 142         if [ -n "${doumount}" ]
 143         then
 144                 umount "${mountp}"
 145                 rmdir "${mountp}"
 146         fi
 147
 148         echo "${size}"
 149 }
 150
 151 load_keymap ()
 152 {
 153         # Load custom keymap
 154         if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
 155         then
 156                 loadkeys /etc/boottime.kmap.gz
 157         fi
 158 }
 159
 160 setup_loop ()
 161 {
 162         local fspath=${1}
 163         local module=${2}
 164         local pattern=${3}
 165         local offset=${4}
 166         local encryption=${5}
 167         local readonly=${6}
 168
 169         modprobe -q -b "${module}"
 170         udevsettle
 171
 172         for loopdev in ${pattern}
 173         do
 174                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 175                 then
 176                         dev=$(sys2dev "${loopdev}")
 177                         options=''
 178
 179                         if [ -n ${readonly} ]
 180                         then
 181                                 if /sbin/losetup --help 2>&1 | grep -q -- "-r\b"
 182                                 then
 183                                         options="${options} -r"
 184                                 fi
 185                         fi
 186
 187                         if [ 0 -lt "${offset}" ]
 188                         then
 189                                 options="${options} -o ${offset}"
 190                         fi
 191
 192                         if [ -z "${encryption}" ]
 193                         then
 194                                 losetup ${options} "${dev}" "${fspath}"
 195                         else
 196                                 # Loop AES encryption
 197                                 while true
 198                                 do
 199                                         load_keymap
 200
 201                                         echo -n "Enter passphrase for root filesystem: " >&6
 202                                         read -s passphrase
 203                                         echo "${passphrase}" > /tmp/passphrase
 204                                         unset passphrase
 205                                         exec 9</tmp/passphrase
 206                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 207                                         error=${?}
 208                                         exec 9<&-
 209                                         rm -f /tmp/passphrase
 210
 211                                         if [ 0 -eq ${error} ]
 212                                         then
 213                                                 unset error
 214                                                 break
 215                                         fi
 216
 217                                         echo
 218                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 219                                         read answer
 220
 221                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 222                                         then
 223                                                 unset answer
 224                                                 break
 225                                         fi
 226                                 done
 227                         fi
 228
 229                         echo "${dev}"
 230                         return 0
 231                 fi
 232         done
 233
 234         panic "No loop devices available"
 235 }
 236
 237 try_mount ()
 238 {
 239         dev="${1}"
 240         mountp="${2}"
 241         opts="${3}"
 242
 243         old_mountp="$(where_is_mounted ${dev})"
 244
 245         if [ -n "${old_mountp}" ]
 246         then
 247                 mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
 248                 mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
 249         else
 250                 mount -t $(get_fstype "${dev}") -o "${opts}" "${dev}" "${mountp}" || panic "Cannot mount ${dev} on ${mountp}"
 251         fi
 252 }
 253
 254 find_cow_device ()
 255 {
 256         pers_label="${1}"
 257         cow_backing="/${pers_label}-backing"
 258
 259         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 260         do
 261                 for dev in $(subdevices "${sysblock}")
 262                 do
 263                         devname=$(sys2dev "${dev}")
 264
 265                         if [ "$(/lib/udev/vol_id -l ${devname} 2>/dev/null)" = "${pers_label}" ]
 266                         then
 267                                 echo "${devname}"
 268                                 return
 269                         fi
 270
 271                         case "$(get_fstype ${devname})" in
 272                                 vfat|ext2|ext3|jffs2)
 273                                         mkdir -p "${cow_backing}"
 274                                         try_mount "${devname}" "${cow_backing}" "rw"
 275
 276                                         if [ -f "${cow_backing}/${pers_label}" ]
 277                                         then
 278                                                 echo $(setup_loop "${cow_backing}/${pers_label}" "loop" "/sys/block/loop*")
 279                                                 return 0
 280                                         else
 281                                                 umount ${cow_backing}
 282                                         fi
 283                                         ;;
 284                                 *)
 285                                         ;;
 286                         esac
 287                 done
 288         done
 289 }
 290
 291 find_files ()
 292 {
 293         # return the first of ${filenames} found on vfat and ext2/ext3 devices
 294         # FIXME: merge with above function
 295
 296         filenames="${1}"
 297         snap_backing="/snap-backing"
 298
 299         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 300         do
 301                 for dev in $(subdevices "${sysblock}")
 302                 do
 303                         devname=$(sys2dev "${dev}")
 304                         devfstype="$(get_fstype ${devname})"
 305
 306                         if is_supported_fs ${devfstype}
 307                         then
 308                                 mkdir -p "${snap_backing}"
 309                                 try_mount "${devname}" "${snap_backing}" "ro"
 310
 311                                 for filename in ${filenames}
 312                                         do
 313                                         if [ -f "${snap_backing}/${filename}" ]
 314                                         then
 315                                                 echo "${devname} ${snap_backing} ${filename}"
 316                                                 return 0
 317                                         fi
 318                                 done
 319
 320                                 umount ${snap_backing}
 321                         fi
 322                 done
 323         done
 324 }
 325
 326 get_mac ()
 327 {
 328         mac=""
 329
 330         for adaptor in /sys/class/net/*
 331         do
 332                 status="$(cat ${adaptor}/iflink)"
 333
 334                 if [ "${status}" -eq 2 ]
 335                 then
 336                         mac="$(cat ${adaptor}/address)"
 337                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
 338                 fi
 339         done
 340
 341         echo ${mac}
 342 }
 343
 344 is_luks()
 345 {
 346     devname="${1}"
 347     if [ -x /sbin/cryptsetup ]
 348     then
 349         /sbin/cryptsetup isLuks "${devname}" 2>/dev/null || ret=${?}
 350         return ${ret}
 351     else
 352         return 1
 353     fi
 354
 355 }