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 ${r}
  30 }
  31
  32 is_supported_fs ()
  33 {
  34         fstype="${1}"
  35
  36         # Validate input first
  37         if [ -z "${fstype}" ]
  38         then
  39                 return 1
  40         fi
  41
  42         # Try to look if it is already supported by the kernel
  43         if grep -q ${fstype} /proc/filesystems
  44         then
  45                 return 0
  46         else
  47                 # Then try to add support for it the gentle way using the initramfs capabilities
  48                 modprobe ${fstype}
  49                 if grep -q ${fstype} /proc/filesystems
  50                 then
  51                         return 0
  52                 # Then try the hard way if /root is already reachable
  53                 else
  54                         kmodule="/root/lib/modules/`uname -r`/${fstype}/${fstype}.ko"
  55                         if [ -e "${kmodule}" ]
  56                         then
  57                                 insmod "${kmodule}"
  58                                 if grep -q ${fstype} /proc/filesystems
  59                                 then
  60                                         return 0
  61                                 fi
  62                         fi
  63                 fi
  64         fi
  65
  66         return 1
  67 }
  68
  69 get_fstype ()
  70 {
  71         local FSTYPE
  72         local FSSIZE
  73
  74         # fstype misreports LUKS devices
  75         if is_luks "${1}"
  76         then
  77             /lib/udev/vol_id -t ${1} 2>/dev/null
  78             return
  79         fi
  80
  81         eval $(fstype < ${1})
  82
  83         if [ "${FSTYPE}" != "unknown" ]
  84         then
  85                 echo ${FSTYPE}
  86                 return 0
  87         fi
  88
  89         /lib/udev/vol_id -t ${1} 2>/dev/null
  90 }
  91
  92 where_is_mounted ()
  93 {
  94         device=${1}
  95
  96         if grep -q "^${device} " /proc/mounts
  97         then
  98                 # return the first found
  99                 grep "^${device} " /proc/mounts | cut -f2 -d ' '
 100         fi
 101 }
 102
 103 lastline ()
 104 {
 105         while read lines
 106         do
 107                 line=${lines}
 108         done
 109
 110         echo "${line}"
 111 }
 112
 113 base_path ()
 114 {
 115         testpath="${1}"
 116         mounts="$(awk '{print $2}' /proc/mounts)"
 117         testpath="$(busybox realpath ${testpath})"
 118
 119         while true
 120         do
 121                 if echo "${mounts}" | grep -qs "^${testpath}"
 122                 then
 123                         set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
 124                         echo ${1}
 125                         break
 126                 else
 127                         testpath=$(dirname $testpath)
 128                 fi
 129         done
 130 }
 131
 132 fs_size ()
 133 {
 134         # Returns used/free fs kbytes + 5% more
 135         # You could pass a block device as ${1} or the mount point as ${2}
 136
 137         dev="${1}"
 138         mountp="${2}"
 139         used="${3}"
 140
 141         if [ -z "${mountp}" ]
 142         then
 143                 mountp="$(where_is_mounted ${dev})"
 144
 145                 if [ -z "${mountp}" ]
 146                 then
 147                         mountp="/mnt/tmp_fs_size"
 148
 149                         mkdir -p "${mountp}"
 150                         mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}"
 151
 152                         doumount=1
 153                 fi
 154         fi
 155
 156         if [ "${used}" = "used" ]
 157         then
 158                 size=$(du -ks ${mountp} | cut -f1)
 159                 size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
 160         else
 161                 # free space
 162                 size="$(df -k | grep -s ${mountp} | awk '{print $4}')"
 163         fi
 164
 165         if [ -n "${doumount}" ]
 166         then
 167                 umount "${mountp}"
 168                 rmdir "${mountp}"
 169         fi
 170
 171         echo "${size}"
 172 }
 173
 174 load_keymap ()
 175 {
 176         # Load custom keymap
 177         if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
 178         then
 179                 loadkeys /etc/boottime.kmap.gz
 180         fi
 181 }
 182
 183 setup_loop ()
 184 {
 185         local fspath=${1}
 186         local module=${2}
 187         local pattern=${3}
 188         local offset=${4}
 189         local encryption=${5}
 190         local readonly=${6}
 191
 192         modprobe -q -b "${module}"
 193
 194         if [ -x /sbin/udevadm ]
 195         then
 196                 # lenny
 197                 udevadm settle
 198         else
 199                 # etch
 200                 udevsettle
 201         fi
 202
 203         for loopdev in ${pattern}
 204         do
 205                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 206                 then
 207                         dev=$(sys2dev "${loopdev}")
 208                         options=''
 209
 210                         if [ -n ${readonly} ]
 211                         then
 212                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 213                                 then
 214                                         options="${options} -r"
 215                                 fi
 216                         fi
 217
 218                         if [ 0 -lt "${offset}" ]
 219                         then
 220                                 options="${options} -o ${offset}"
 221                         fi
 222
 223                         if [ -z "${encryption}" ]
 224                         then
 225                                 losetup ${options} "${dev}" "${fspath}"
 226                         else
 227                                 # Loop AES encryption
 228                                 while true
 229                                 do
 230                                         load_keymap
 231
 232                                         echo -n "Enter passphrase for root filesystem: " >&6
 233                                         read -s passphrase
 234                                         echo "${passphrase}" > /tmp/passphrase
 235                                         unset passphrase
 236                                         exec 9</tmp/passphrase
 237                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 238                                         error=${?}
 239                                         exec 9<&-
 240                                         rm -f /tmp/passphrase
 241
 242                                         if [ 0 -eq ${error} ]
 243                                         then
 244                                                 unset error
 245                                                 break
 246                                         fi
 247
 248                                         echo
 249                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 250                                         read answer
 251
 252                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 253                                         then
 254                                                 unset answer
 255                                                 break
 256                                         fi
 257                                 done
 258                         fi
 259
 260                         echo "${dev}"
 261                         return 0
 262                 fi
 263         done
 264
 265         panic "No loop devices available"
 266 }
 267
 268 try_mount ()
 269 {
 270         dev="${1}"
 271         mountp="${2}"
 272         opts="${3}"
 273
 274         old_mountp="$(where_is_mounted ${dev})"
 275
 276         if [ -n "${old_mountp}" ]
 277         then
 278                 mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
 279                 mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
 280         else
 281                 mount -t $(get_fstype "${dev}") -o "${opts}" "${dev}" "${mountp}" || panic "Cannot mount ${dev} on ${mountp}"
 282         fi
 283 }
 284
 285 find_cow_device ()
 286 {
 287         pers_label="${1}"
 288         cow_backing="/${pers_label}-backing"
 289
 290         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 291         do
 292                 for dev in $(subdevices "${sysblock}")
 293                 do
 294                         devname=$(sys2dev "${dev}")
 295
 296                         if [ "$(/lib/udev/vol_id -l ${devname} 2>/dev/null)" = "${pers_label}" ]
 297                         then
 298                                 echo "${devname}"
 299                                 return
 300                         fi
 301
 302                         case "$(get_fstype ${devname})" in
 303                                 vfat|ext2|ext3|jffs2)
 304                                         mkdir -p "${cow_backing}"
 305                                         try_mount "${devname}" "${cow_backing}" "rw"
 306
 307                                         if [ -f "${cow_backing}/${pers_label}" ]
 308                                         then
 309                                                 echo $(setup_loop "${cow_backing}/${pers_label}" "loop" "/sys/block/loop*")
 310                                                 return 0
 311                                         else
 312                                                 umount ${cow_backing}
 313                                         fi
 314                                         ;;
 315                                 *)
 316                                         ;;
 317                         esac
 318                 done
 319         done
 320 }
 321
 322 find_files ()
 323 {
 324         # return the first of ${filenames} found on vfat and ext2/ext3 devices
 325         # FIXME: merge with above function
 326
 327         filenames="${1}"
 328         snap_backing="/snap-backing"
 329
 330         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 331         do
 332                 for dev in $(subdevices "${sysblock}")
 333                 do
 334                         devname=$(sys2dev "${dev}")
 335                         devfstype="$(get_fstype ${devname})"
 336
 337                         if is_supported_fs ${devfstype}
 338                         then
 339                                 mkdir -p "${snap_backing}"
 340                                 try_mount "${devname}" "${snap_backing}" "ro"
 341
 342                                 for filename in ${filenames}
 343                                         do
 344                                         if [ -f "${snap_backing}/${filename}" ]
 345                                         then
 346                                                 echo "${devname} ${snap_backing} ${filename}"
 347                                                 return 0
 348                                         fi
 349                                 done
 350
 351                                 umount ${snap_backing}
 352                         fi
 353                 done
 354         done
 355 }
 356
 357 get_mac ()
 358 {
 359         mac=""
 360
 361         for adaptor in /sys/class/net/*
 362         do
 363                 status="$(cat ${adaptor}/iflink)"
 364
 365                 if [ "${status}" -eq 2 ]
 366                 then
 367                         mac="$(cat ${adaptor}/address)"
 368                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
 369                 fi
 370         done
 371
 372         echo ${mac}
 373 }
 374
 375 is_luks()
 376 {
 377     devname="${1}"
 378     if [ -x /sbin/cryptsetup ]
 379     then
 380         /sbin/cryptsetup isLuks "${devname}" 2>/dev/null || ret=${?}
 381         return ${ret}
 382     else
 383         return 1
 384     fi
 385
 386 }