scripts/live-helpers

   1 # live-boot helper functions, used by live-boot on boot and by live-snapshot
   2
   3 if [ ! -x "/bin/fstype" ]
   4 then
   5         # klibc not in path -> not in initramfs
   6         export PATH="${PATH}:/usr/lib/klibc/bin"
   7 fi
   8
   9 # handle upgrade path from old udev (using udevinfo) to
  10 # recent versions of udev (using udevadm info)
  11 if [ -x /sbin/udevadm ]
  12 then
  13         udevinfo='/sbin/udevadm info'
  14 else
  15         udevinfo='udevinfo'
  16 fi
  17
  18 sys2dev ()
  19 {
  20         sysdev=${1#/sys}
  21         echo "/dev/$($udevinfo -q name -p ${sysdev} 2>/dev/null|| echo ${sysdev##*/})"
  22 }
  23
  24 subdevices ()
  25 {
  26         sysblock=${1}
  27         r=""
  28
  29         for dev in "${sysblock}"/* "${sysblock}"
  30         do
  31                 if [ -e "${dev}/dev" ]
  32                 then
  33                         r="${r} ${dev}"
  34                 fi
  35         done
  36
  37         echo ${r}
  38 }
  39
  40 is_supported_fs ()
  41 {
  42         fstype="${1}"
  43
  44         # Validate input first
  45         if [ -z "${fstype}" ]
  46         then
  47                 return 1
  48         fi
  49
  50         # Try to look if it is already supported by the kernel
  51         if grep -q ${fstype} /proc/filesystems
  52         then
  53                 return 0
  54         else
  55                 # Then try to add support for it the gentle way using the initramfs capabilities
  56                 modprobe ${fstype}
  57                 if grep -q ${fstype} /proc/filesystems
  58                 then
  59                         return 0
  60                 # Then try the hard way if /root is already reachable
  61                 else
  62                         kmodule="/root/lib/modules/`uname -r`/${fstype}/${fstype}.ko"
  63                         if [ -e "${kmodule}" ]
  64                         then
  65                                 insmod "${kmodule}"
  66                                 if grep -q ${fstype} /proc/filesystems
  67                                 then
  68                                         return 0
  69                                 fi
  70                         fi
  71                 fi
  72         fi
  73
  74         return 1
  75 }
  76
  77 get_fstype ()
  78 {
  79         /sbin/blkid -s TYPE -o value $1 2>/dev/null
  80 }
  81
  82 where_is_mounted ()
  83 {
  84         device=${1}
  85
  86         if grep -q "^${device} " /proc/mounts
  87         then
  88                 # return the first found
  89                 grep -m1 "^${device} " /proc/mounts | cut -f2 -d ' '
  90         fi
  91 }
  92
  93 lastline ()
  94 {
  95         while read lines
  96         do
  97                 line=${lines}
  98         done
  99
 100         echo "${line}"
 101 }
 102
 103 base_path ()
 104 {
 105         testpath="${1}"
 106         mounts="$(awk '{print $2}' /proc/mounts)"
 107         testpath="$(busybox realpath ${testpath})"
 108
 109         while true
 110         do
 111                 if echo "${mounts}" | grep -qs "^${testpath}"
 112                 then
 113                         set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
 114                         echo ${1}
 115                         break
 116                 else
 117                         testpath=$(dirname $testpath)
 118                 fi
 119         done
 120 }
 121
 122 fs_size ()
 123 {
 124         # Returns used/free fs kbytes + 5% more
 125         # You could pass a block device as ${1} or the mount point as ${2}
 126
 127         dev="${1}"
 128         mountp="${2}"
 129         used="${3}"
 130
 131         if [ -z "${mountp}" ]
 132         then
 133                 mountp="$(where_is_mounted ${dev})"
 134
 135                 if [ -z "${mountp}" ]
 136                 then
 137                         mountp="/mnt/tmp_fs_size"
 138
 139                         mkdir -p "${mountp}"
 140                         mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}" || log_warning_msg "cannot mount -t $(get_fstype ${dev}) -o ro ${dev} ${mountp}"
 141
 142                         doumount=1
 143                 fi
 144         fi
 145
 146         if [ "${used}" = "used" ]
 147         then
 148                 size=$(du -ks ${mountp} | cut -f1)
 149                 size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
 150         else
 151                 # free space
 152                 size="$(df -k | grep -s ${mountp} | awk '{print $4}')"
 153         fi
 154
 155         if [ -n "${doumount}" ]
 156         then
 157                 umount "${mountp}" || log_warning_msg "cannot umount ${mountp}"
 158                 rmdir "${mountp}"
 159         fi
 160
 161         echo "${size}"
 162 }
 163
 164 load_keymap ()
 165 {
 166         # Load custom keymap
 167         if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
 168         then
 169                 loadkeys /etc/boottime.kmap.gz
 170         fi
 171 }
 172
 173 setup_loop ()
 174 {
 175         local fspath=${1}
 176         local module=${2}
 177         local pattern=${3}
 178         local offset=${4}
 179         local encryption=${5}
 180         local readonly=${6}
 181
 182         # the output of setup_loop is evaluated in other functions,
 183         # modprobe leaks kernel options like "libata.dma=0"
 184         # as "options libata dma=0" on stdout, causing serious
 185         # problems therefor, so instead always avoid output to stdout
 186         modprobe -q -b "${module}" 1>/dev/null
 187
 188         udevadm settle
 189
 190         for loopdev in ${pattern}
 191         do
 192                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 193                 then
 194                         dev=$(sys2dev "${loopdev}")
 195                         options=''
 196
 197                         if [ -n "${readonly}" ]
 198                         then
 199                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 200                                 then
 201                                         options="${options} -r"
 202                                 fi
 203                         fi
 204
 205                         if [ 0 -lt "${offset}" ]
 206                         then
 207                                 options="${options} -o ${offset}"
 208                         fi
 209
 210                         if [ -z "${encryption}" ]
 211                         then
 212                                 losetup ${options} "${dev}" "${fspath}"
 213                         else
 214                                 # Loop AES encryption
 215                                 while true
 216                                 do
 217                                         load_keymap
 218
 219                                         echo -n "Enter passphrase for root filesystem: " >&6
 220                                         read -s passphrase
 221                                         echo "${passphrase}" > /tmp/passphrase
 222                                         unset passphrase
 223                                         exec 9</tmp/passphrase
 224                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 225                                         error=${?}
 226                                         exec 9<&-
 227                                         rm -f /tmp/passphrase
 228
 229                                         if [ 0 -eq ${error} ]
 230                                         then
 231                                                 unset error
 232                                                 break
 233                                         fi
 234
 235                                         echo
 236                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 237                                         read answer
 238
 239                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 240                                         then
 241                                                 unset answer
 242                                                 break
 243                                         fi
 244                                 done
 245                         fi
 246
 247                         echo "${dev}"
 248                         return 0
 249                 fi
 250         done
 251
 252         panic "No loop devices available"
 253 }
 254
 255 try_mount ()
 256 {
 257         dev="${1}"
 258         mountp="${2}"
 259         opts="${3}"
 260         fstype="${4}"
 261
 262         old_mountp="$(where_is_mounted ${dev})"
 263
 264         if [ -n "${old_mountp}" ]
 265         then
 266                 if [ "${opts}" != "ro" ]
 267                 then
 268                         mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
 269                 fi
 270
 271                 mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
 272         else
 273                 if [ -z "${fstype}" ]
 274                 then
 275                         fstype=$(get_fstype "${dev}")
 276                 fi
 277                 mount -t "${fstype}" -o "${opts}" "${dev}" "${mountp}" || \
 278                 ( echo "SKIPPING: Cannot mount ${dev} on ${mountp}, fstype=${fstype}, options=${opts}" > live-boot.log && return 0 )
 279         fi
 280 }
 281
 282 find_cow_device ()
 283 {
 284         # Returns a device containing a partition labeled "${pers_label}" or containing a file named the same way
 285         #  in the latter case the partition containing the file is left mounted
 286         #  if is not in black_listed_devices
 287         pers_label="${1}"
 288         cow_backing="/${pers_label}-backing"
 289         black_listed_devices="${2}"
 290
 291         if [ -z "${PERSISTENT_PATH}" ]
 292         then
 293                 pers_fpath=${cow_backing}/${pers_label}
 294         else
 295                 pers_fpath=${cow_backing}/${PERSISTENT_PATH}/${pers_label}
 296         fi
 297
 298         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 299         do
 300                 fulldevname=$(sys2dev "${sysblock}")
 301
 302                 if echo "${black_listed_devices}" | grep -q -w "${fulldevname}"
 303                 then
 304                         # skip this device entirely
 305                         break
 306                 fi
 307
 308                 for dev in $(subdevices "${sysblock}")
 309                 do
 310                         devname=$(sys2dev "${dev}")
 311
 312                         if echo "${black_listed_devices}" | grep -q -w "${devname}"
 313                         then
 314                                 # skip this subdevice
 315                                 break
 316                         fi
 317
 318                         # Checking for a luks device
 319                         if [ "${PERSISTENT}" = "cryptsetup" ] && [ -e /sbin/cryptsetup ] && /sbin/cryptsetup isLuks ${devname}
 320                         then
 321                                 while true
 322                                 do
 323                                         load_keymap
 324
 325                                         /lib/cryptsetup/askpass "Enter passphrase for ${pers_label} on ${devname}: " | /sbin/cryptsetup -T 1 luksOpen ${devname} $(basename ${devname}) --key-file=-
 326                                         error=${?}
 327
 328                                         devname="/dev/mapper/$(basename ${devname})"
 329
 330                                         if [ 0 -eq ${error} ]
 331                                         then
 332                                                 unset error
 333                                                 break
 334                                         fi
 335
 336                                         echo
 337                                         echo -n "There was an error decrypting ${devname} ... Retry? [Y/n] " >&6
 338                                         read answer
 339
 340                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 341                                         then
 342                                                 unset answer
 343                                                 break
 344                                         fi
 345                                 done
 346                         fi
 347
 348                         if [ "$(/sbin/blkid -s LABEL -o value $devname 2>/dev/null)" = "${pers_label}" ]
 349                         then
 350                                 echo "${devname}"
 351                                 return 0
 352                         fi
 353
 354                         if [ "${PERSISTENT}" = "nofiles" ]
 355                         then
 356                                 # do not mount the device to find for image files
 357                                 # just skip this
 358                                 continue
 359                         fi
 360
 361                         case "$(get_fstype ${devname})" in
 362                                 vfat|ext2|ext3|ext4|jffs2)
 363                                         mkdir -p "${cow_backing}"
 364                                         if try_mount "${devname}" "${cow_backing}" "rw"
 365                                         then
 366                                                 if [ -f "${pers_fpath}" ]
 367                                                 then
 368                                                         echo $(setup_loop "${pers_fpath}" "loop" "/sys/block/loop*")
 369                                                         return 0
 370                                                 else
 371                                                         umount ${cow_backing} > /dev/null 2>&1 || true
 372                                                 fi
 373                                         fi
 374                                         ;;
 375                                 *)
 376                                         ;;
 377                         esac
 378                 done
 379         done
 380         return 1
 381 }
 382
 383 find_files ()
 384 {
 385         # return the a string composed by device name, mountpoint an the first of ${filenames} found on a supported partition
 386         # FIXME: merge with above function
 387
 388         filenames="${1}"
 389         snap_backing="/snap-backing"
 390         black_listed_devices="${2}"
 391
 392         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 393         do
 394                 fulldevname=$(sys2dev "${sysblock}")
 395
 396                 if echo "${black_listed_devices}" | grep -q -w "${fulldevname}"
 397                 then
 398                         # skip this device entirely
 399                         break
 400                 fi
 401
 402                 for dev in $(subdevices "${sysblock}")
 403                 do
 404                         devname=$(sys2dev "${dev}")
 405                         devfstype="$(get_fstype ${devname})"
 406
 407                         if echo "${black_listed_devices}" | grep -q -w "${devname}"
 408                         then
 409                                 # skip this subdevice
 410                                 break
 411                         fi
 412
 413                         if is_supported_fs ${devfstype}
 414                         then
 415                                 mkdir -p "${snap_backing}"
 416
 417                                 if try_mount "${devname}" "${snap_backing}" "ro" "${devfstype}"
 418                                 then
 419                                         for filename in ${filenames}
 420                                         do
 421                                                 if [ -f "${snap_backing}/${filename}" ]
 422                                                 then
 423                                                         echo "${devname} ${snap_backing} ${filename}"
 424                                                         umount ${snap_backing}
 425                                                         return 0
 426                                                 fi
 427                                         done
 428                                 fi
 429
 430                                 umount ${snap_backing}
 431                         fi
 432                 done
 433         done
 434 }
 435
 436 get_mac ()
 437 {
 438         mac=""
 439
 440         for adaptor in /sys/class/net/*
 441         do
 442                 status="$(cat ${adaptor}/iflink)"
 443
 444                 if [ "${status}" -eq 2 ]
 445                 then
 446                         mac="$(cat ${adaptor}/address)"
 447                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
 448                 fi
 449         done
 450
 451         echo ${mac}
 452 }
 453
 454 is_luks()
 455 {
 456     devname="${1}"
 457     if [ -x /sbin/cryptsetup ]
 458     then
 459         /sbin/cryptsetup isLuks "${devname}" 2>/dev/null || ret=${?}
 460         return ${ret}
 461     else
 462         return 1
 463     fi
 464
 465 }