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 ${r}
  38 }
  39
  40 storage_devices()
  41 {
  42         black_listed_devices="${1}"
  43         white_listed_devices="${2}"
  44
  45         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "loop|ram|fd")
  46         do
  47                 fulldevname=$(sys2dev "${sysblock}")
  48
  49                 if echo "${black_listed_devices}" | grep -qw "${fulldevname}" || \
  50                         [ -n "${white_listed_devices}" ] && \
  51                         echo "${white_listed_devices}" | grep -vqw "${fulldevname}"
  52                 then
  53                         # skip this device entirely
  54                         continue
  55                 fi
  56
  57                 for dev in $(subdevices "${sysblock}")
  58                 do
  59                         devname=$(sys2dev "${dev}")
  60
  61                         if echo "${black_listed_devices}" | grep -qw "${devname}"
  62                         then
  63                                 # skip this subdevice
  64                                 continue
  65                         else
  66                                 echo "${devname}"
  67                         fi
  68                 done
  69         done
  70 }
  71
  72 is_supported_fs ()
  73 {
  74         fstype="${1}"
  75
  76         # Validate input first
  77         if [ -z "${fstype}" ]
  78         then
  79                 return 1
  80         fi
  81
  82         # Try to look if it is already supported by the kernel
  83         if grep -q ${fstype} /proc/filesystems
  84         then
  85                 return 0
  86         else
  87                 # Then try to add support for it the gentle way using the initramfs capabilities
  88                 modprobe ${fstype}
  89                 if grep -q ${fstype} /proc/filesystems
  90                 then
  91                         return 0
  92                 # Then try the hard way if /root is already reachable
  93                 else
  94                         kmodule="/root/lib/modules/`uname -r`/${fstype}/${fstype}.ko"
  95                         if [ -e "${kmodule}" ]
  96                         then
  97                                 insmod "${kmodule}"
  98                                 if grep -q ${fstype} /proc/filesystems
  99                                 then
 100                                         return 0
 101                                 fi
 102                         fi
 103                 fi
 104         fi
 105
 106         return 1
 107 }
 108
 109 get_fstype ()
 110 {
 111         /sbin/blkid -s TYPE -o value $1 2>/dev/null
 112 }
 113
 114 where_is_mounted ()
 115 {
 116         device=${1}
 117
 118         if grep -q "^${device} " /proc/mounts
 119         then
 120                 # return the first found
 121                 grep -m1 "^${device} " /proc/mounts | cut -f2 -d ' '
 122         fi
 123 }
 124
 125 lastline ()
 126 {
 127         while read lines
 128         do
 129                 line=${lines}
 130         done
 131
 132         echo "${line}"
 133 }
 134
 135 base_path ()
 136 {
 137         testpath="${1}"
 138         mounts="$(awk '{print $2}' /proc/mounts)"
 139         testpath="$(busybox realpath ${testpath})"
 140
 141         while true
 142         do
 143                 if echo "${mounts}" | grep -qs "^${testpath}"
 144                 then
 145                         set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
 146                         echo ${1}
 147                         break
 148                 else
 149                         testpath=$(dirname $testpath)
 150                 fi
 151         done
 152 }
 153
 154 fs_size ()
 155 {
 156         # Returns used/free fs kbytes + 5% more
 157         # You could pass a block device as ${1} or the mount point as ${2}
 158
 159         dev="${1}"
 160         mountp="${2}"
 161         used="${3}"
 162
 163         if [ -z "${mountp}" ]
 164         then
 165                 mountp="$(where_is_mounted ${dev})"
 166
 167                 if [ -z "${mountp}" ]
 168                 then
 169                         mountp="/mnt/tmp_fs_size"
 170
 171                         mkdir -p "${mountp}"
 172                         mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}" || log_warning_msg "cannot mount -t $(get_fstype ${dev}) -o ro ${dev} ${mountp}"
 173
 174                         doumount=1
 175                 fi
 176         fi
 177
 178         if [ "${used}" = "used" ]
 179         then
 180                 size=$(du -ks ${mountp} | cut -f1)
 181                 size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
 182         else
 183                 # free space
 184                 size="$(df -k | grep -s ${mountp} | awk '{print $4}')"
 185         fi
 186
 187         if [ -n "${doumount}" ]
 188         then
 189                 umount "${mountp}" || log_warning_msg "cannot umount ${mountp}"
 190                 rmdir "${mountp}"
 191         fi
 192
 193         echo "${size}"
 194 }
 195
 196 load_keymap ()
 197 {
 198         # Load custom keymap
 199         if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
 200         then
 201                 loadkeys /etc/boottime.kmap.gz
 202         fi
 203 }
 204
 205 setup_loop ()
 206 {
 207         local fspath=${1}
 208         local module=${2}
 209         local pattern=${3}
 210         local offset=${4}
 211         local encryption=${5}
 212         local readonly=${6}
 213
 214         # the output of setup_loop is evaluated in other functions,
 215         # modprobe leaks kernel options like "libata.dma=0"
 216         # as "options libata dma=0" on stdout, causing serious
 217         # problems therefor, so instead always avoid output to stdout
 218         modprobe -q -b "${module}" 1>/dev/null
 219
 220         udevadm settle
 221
 222         for loopdev in ${pattern}
 223         do
 224                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 225                 then
 226                         dev=$(sys2dev "${loopdev}")
 227                         options=''
 228
 229                         if [ -n "${readonly}" ]
 230                         then
 231                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 232                                 then
 233                                         options="${options} -r"
 234                                 fi
 235                         fi
 236
 237                         if [ 0 -lt "${offset}" ]
 238                         then
 239                                 options="${options} -o ${offset}"
 240                         fi
 241
 242                         if [ -z "${encryption}" ]
 243                         then
 244                                 losetup ${options} "${dev}" "${fspath}"
 245                         else
 246                                 # Loop AES encryption
 247                                 while true
 248                                 do
 249                                         load_keymap
 250
 251                                         echo -n "Enter passphrase for root filesystem: " >&6
 252                                         read -s passphrase
 253                                         echo "${passphrase}" > /tmp/passphrase
 254                                         unset passphrase
 255                                         exec 9</tmp/passphrase
 256                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 257                                         error=${?}
 258                                         exec 9<&-
 259                                         rm -f /tmp/passphrase
 260
 261                                         if [ 0 -eq ${error} ]
 262                                         then
 263                                                 unset error
 264                                                 break
 265                                         fi
 266
 267                                         echo
 268                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 269                                         read answer
 270
 271                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 272                                         then
 273                                                 unset answer
 274                                                 break
 275                                         fi
 276                                 done
 277                         fi
 278
 279                         echo "${dev}"
 280                         return 0
 281                 fi
 282         done
 283
 284         panic "No loop devices available"
 285 }
 286
 287 try_mount ()
 288 {
 289         dev="${1}"
 290         mountp="${2}"
 291         opts="${3}"
 292         fstype="${4}"
 293
 294         old_mountp="$(where_is_mounted ${dev})"
 295
 296         if [ -n "${old_mountp}" ]
 297         then
 298                 if [ "${opts}" != "ro" ]
 299                 then
 300                         mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
 301                 fi
 302
 303                 mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
 304         else
 305                 if [ -z "${fstype}" ]
 306                 then
 307                         fstype=$(get_fstype "${dev}")
 308                 fi
 309                 mount -t "${fstype}" -o "${opts}" "${dev}" "${mountp}" || \
 310                 ( echo "SKIPPING: Cannot mount ${dev} on ${mountp}, fstype=${fstype}, options=${opts}" > live-boot.log && return 0 )
 311         fi
 312 }
 313
 314 find_persistent_media ()
 315 {
 316         # Scans devices for overlays and snapshots, and returns a whitespace
 317         # separated list of how to use them. Only overlays with a partition
 318         # label or file name in ${overlays} are returned, and ditto for
 319         # snapshots with labels in ${snapshots}.
 320         #
 321         # When scanning a LUKS device, the user will be asked to enter the
 322         # passphrase; on failure to enter it, or if no persistent partitions
 323         # or files were found, the LUKS device is closed.
 324         #
 325         # For a snapshot file the return value is ${label}=${snapdata}", where
 326         # ${snapdata} is the parameter used for try_snap().
 327         #
 328         # For all other cases (overlay/snapshot partition and overlay file) the
 329         # return value is "${label}=${device}", where ${device} a device that
 330         # can mount the content. In the case of an overlay file, the device
 331         # containing the file will remain mounted as a side-effect.
 332         #
 333         # No devices in ${black_listed_devices} will be scanned, and if
 334         # ${white_list_devices} is non-empty, only devices in it will be
 335         # scanned.
 336
 337         overlays="${1}"
 338         snapshots="${2}"
 339         black_listed_devices="${3}"
 340         white_listed_devices="${4}"
 341
 342         for dev in $(storage_devices "${black_listed_devices}" "${white_listed_devices}")
 343         do
 344                 luks_device=""
 345
 346                 # Checking for a luks device
 347                 if [ "${PERSISTENT_ENCRYPTION}" = "luks" ] && [ -e /sbin/cryptsetup ]
 348                 then
 349                         if ! modprobe dm-crypt
 350                         then
 351                                 log_warning_msg "Unable to load module dm-crypt"
 352                                 continue
 353                         fi
 354
 355                         if [ ! -x /lib/cryptsetup/askpass ] || [ ! -x /sbin/cryptsetup ]
 356                         then
 357                                 log_warning_msg "cryptsetup in unavailable"
 358                                 continue
 359                         fi
 360
 361                         if ! /sbin/cryptsetup isLuks ${dev}
 362                         then
 363                                 # skip device since we strictly want luks devices
 364                                 continue
 365                         fi
 366
 367                         load_keymap
 368
 369                         while true
 370                         do
 371                                 /lib/cryptsetup/askpass "Enter passphrase for ${dev}: " | /sbin/cryptsetup -T 1 luksOpen ${dev} $(basename ${dev}) --key-file=-
 372
 373                                 if [ 0 -eq ${?} ]
 374                                 then
 375                                         luks_device="/dev/mapper/$(basename ${dev})"
 376                                         dev="${luks_device}"
 377                                         break
 378                                 fi
 379
 380                                 echo >&6
 381                                 echo -n "There was an error decrypting ${dev} ... Retry? [Y/n] " >&6
 382                                 read answer
 383
 384                                 if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 385                                 then
 386                                         break
 387                                 fi
 388                         done
 389                 fi
 390
 391                 if echo ${PERSISTENT_STORAGE} | grep -qw filesystem
 392                 then
 393                         for label in ${overlays} ${snapshots}
 394                         do
 395                                 if [ "$(/sbin/blkid -s LABEL -o value $dev 2>/dev/null)" = "${label}" ]
 396                                 then
 397                                         overlays=$(echo ${overlays} | sed -e "s|\<${label}\>||")
 398                                         snapshots=$(echo ${snapshots} | sed -e "s|\<${label}\>||")
 399                                         echo "${label}=${dev}"
 400                                         # skip to the next device
 401                                         continue 2
 402                                 fi
 403                         done
 404                 fi
 405
 406                 if echo ${PERSISTENT_STORAGE} | grep -qw file
 407                 then
 408                         devfstype="$(get_fstype ${dev})"
 409                         overlay_on_dev=""
 410                         snapshot_on_dev=""
 411                         backing="/$(basename ${dev})-backing"
 412                         mkdir -p "${backing}"
 413                         if is_supported_fs ${devfstype} && try_mount "${dev}" "${backing}" "rw" "${devfstype}"
 414                         then
 415                                 for label in ${overlays}
 416                                 do
 417                                         path=${backing}/${PERSISTENT_PATH}${label}
 418                                         if [ -f "${path}" ]
 419                                         then
 420                                                 overlays=$(echo ${overlays} | sed -e "s|\<${label}\>||")
 421                                                 overlay_on_dev="yes"
 422                                                 echo "${label}=$(setup_loop "${path}" "loop" "/sys/block/loop*")"
 423                                         fi
 424                                 done
 425
 426                                 for label in ${snapshots}
 427                                 do
 428                                         for ext in squashfs cpio.gz ext2 ext3 ext4 jffs2
 429                                         do
 430                                                 path="${PERSISTENT_PATH}${label}.${ext}"
 431                                                 if [ -f "${backing}/${path}" ]
 432                                                 then
 433                                                         snapshots=$(echo ${snapshots} | sed -e "s|\<${label}\>||")
 434                                                         snapshot_on_dev="yes"
 435                                                         echo "${label}=${dev}:${backing}:${path}"
 436                                                 fi
 437                                         done
 438                                 done
 439                         fi
 440                         if [ -z "${overlay_on_dev}" ]
 441                         then
 442                                 umount ${backing} > /dev/null 2>&1 || true
 443                                 if [ -z "${snapshot_on_dev}" ] && [ -n "${luks_device}" ] && /sbin/cryptsetup status "${luks_device}" 1> /dev/null
 444                                 then
 445                                         /sbin/cryptsetup luksClose "${luks_device}"
 446                                 fi
 447                         fi
 448                 fi
 449         done
 450 }
 451
 452 get_mac ()
 453 {
 454         mac=""
 455
 456         for adaptor in /sys/class/net/*
 457         do
 458                 status="$(cat ${adaptor}/iflink)"
 459
 460                 if [ "${status}" -eq 2 ]
 461                 then
 462                         mac="$(cat ${adaptor}/address)"
 463                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
 464                 fi
 465         done
 466
 467         echo ${mac}
 468 }
 469
 470 is_luks()
 471 {
 472     devname="${1}"
 473     if [ -x /sbin/cryptsetup ]
 474     then
 475         /sbin/cryptsetup isLuks "${devname}" 2>/dev/null || ret=${?}
 476         return ${ret}
 477     else
 478         return 1
 479     fi
 480
 481 }
 482
 483 removable_dev ()
 484 {
 485         output_format="${1}"
 486         want_usb="${2}"
 487         ret=
 488
 489         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
 490         do
 491                 dev_ok=
 492                 if [ "$(cat ${sysblock}/removable)" = "1" ]
 493                 then
 494                         if [ -z "${want_usb}" ]
 495                         then
 496                                 dev_ok="yes"
 497                         else
 498                                 if readlink ${sysblock} | grep -q usb
 499                                 then
 500                                         dev_ok="yes"
 501                                 fi
 502                         fi
 503                 fi
 504
 505                 if [ "${dev_ok}" = "yes" ]
 506                 then
 507                         case "${output_format}" in
 508                                 sys)
 509                                         ret="${ret} ${sysblock}"
 510                                         ;;
 511                                 *)
 512                                         devname=$(sys2dev "${sysblock}")
 513                                         ret="${ret} ${devname}"
 514                                         ;;
 515                         esac
 516                 fi
 517         done
 518
 519         echo "${ret}"
 520 }
 521
 522 removable_usb_dev ()
 523 {
 524         output_format="${1}"
 525
 526         removable_dev "${output_format}" "want_usb"
 527 }
 528
 529 non_removable_dev ()
 530 {
 531         output_format="${1}"
 532         ret=
 533
 534         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
 535         do
 536                 if [ "$(cat ${sysblock}/removable)" = "0" ]
 537                 then
 538                         case "${output_format}" in
 539                                 sys)
 540                                         ret="${ret} ${sysblock}"
 541                                         ;;
 542                                 *)
 543                                         devname=$(sys2dev "${sysblock}")
 544                                         ret="${ret} ${devname}"
 545                                         ;;
 546                         esac
 547                 fi
 548         done
 549
 550         echo "${ret}"
 551 }