components/9990-misc-helpers.sh

   1 #!/bin/sh
   2
   3 #set -e
   4
   5 is_live_path()
   6 {
   7         DIRECTORY="${1}/${LIVE_MEDIA_PATH}"
   8         for FILESYSTEM in squashfs ext2 ext3 ext4 xfs dir jffs
   9         do
  10                 if ls "${DIRECTORY}/"*.${FILESYSTEM} > /dev/null 2>&1
  11                 then
  12                         return 0
  13                 fi
  14         done
  15         return 1
  16 }
  17
  18 matches_uuid ()
  19 {
  20         if [ "${IGNORE_UUID}" ] || [ ! -e /conf/uuid.conf ]
  21         then
  22                 return 0
  23         fi
  24
  25         path="${1}"
  26         uuid="$(cat /conf/uuid.conf)"
  27
  28         for try_uuid_file in "${path}/.disk/live-uuid"*
  29         do
  30                 [ -e "${try_uuid_file}" ] || continue
  31
  32                 try_uuid="$(cat "${try_uuid_file}")"
  33
  34                 if [ "${uuid}" = "${try_uuid}" ]
  35                 then
  36                         return 0
  37                 fi
  38         done
  39
  40         return 1
  41 }
  42
  43 get_backing_device ()
  44 {
  45         case "${1}" in
  46                 *.squashfs|*.ext2|*.ext3|*.ext4|*.jffs2)
  47                         echo $(setup_loop "${1}" "loop" "/sys/block/loop*" '0' "${LIVE_MEDIA_ENCRYPTION}" "${2}")
  48                         ;;
  49
  50                 *.dir)
  51                         echo "directory"
  52                         ;;
  53
  54                 *)
  55                         panic "Unrecognized live filesystem: ${1}"
  56                         ;;
  57         esac
  58 }
  59
  60 mount_images_in_directory ()
  61 {
  62         directory="${1}"
  63         rootmnt="${2}"
  64         mac="${3}"
  65
  66         if is_live_path "${directory}"
  67         then
  68                 [ -n "${mac}" ] && adddirectory="${directory}/${LIVE_MEDIA_PATH}/${mac}"
  69                 setup_unionfs "${directory}/${LIVE_MEDIA_PATH}" "${rootmnt}" "${adddirectory}"
  70         else
  71                 panic "No supported filesystem images found at /${LIVE_MEDIA_PATH}."
  72         fi
  73 }
  74
  75 is_nice_device ()
  76 {
  77         sysfs_path="${1#/sys}"
  78
  79         if udevadm test-builtin path_id "${sysfs_path}" | egrep -q "ID_PATH=(usb|pci-[^-]*-(ide|sas|scsi|usb|virtio)|platform-sata_mv|platform-orion-ehci|platform-mmc|platform-mxsdhci)"
  80         then
  81                 return 0
  82         elif echo "${sysfs_path}" | grep -q '^/block/vd[a-z]$'
  83         then
  84                 return 0
  85         elif echo ${sysfs_path} | grep -q "^/block/dm-"
  86         then
  87                 return 0
  88         elif echo ${sysfs_path} | grep -q "^/block/mtdblock"
  89         then
  90                 return 0
  91         fi
  92
  93         return 1
  94 }
  95
  96 check_dev ()
  97 {
  98         sysdev="${1}"
  99         devname="${2}"
 100         skip_uuid_check="${3}"
 101
 102         # support for fromiso=.../isofrom=....
 103         if [ -n "$FROMISO" ]
 104         then
 105                 ISO_DEVICE=$(dirname $FROMISO)
 106                 if ! [ -b $ISO_DEVICE ]
 107                 then
 108                         # to support unusual device names like /dev/cciss/c0d0p1
 109                         # as well we have to identify the block device name, let's
 110                         # do that for up to 15 levels
 111                         i=15
 112                         while [ -n "$ISO_DEVICE" ] && [ "$i" -gt 0 ]
 113                         do
 114                                 ISO_DEVICE=$(dirname ${ISO_DEVICE})
 115                                 [ -b "$ISO_DEVICE" ] && break
 116                                 i=$(($i -1))
 117                         done
 118                 fi
 119
 120                 if [ "$ISO_DEVICE" = "/" ]
 121                 then
 122                         echo "Warning: device for bootoption fromiso= ($FROMISO) not found.">>/boot.log
 123                 else
 124                         fs_type=$(get_fstype "${ISO_DEVICE}")
 125                         if is_supported_fs ${fs_type}
 126                         then
 127                                 mkdir /live/fromiso
 128                                 mount -t $fs_type "$ISO_DEVICE" /live/fromiso
 129                                 ISO_NAME="$(echo $FROMISO | sed "s|$ISO_DEVICE||")"
 130                                 loopdevname=$(setup_loop "/live/fromiso/${ISO_NAME}" "loop" "/sys/block/loop*" "" '')
 131                                 devname="${loopdevname}"
 132                         else
 133                                 echo "Warning: unable to mount $ISO_DEVICE." >>/boot.log
 134                         fi
 135                 fi
 136         fi
 137
 138         if [ -z "${devname}" ]
 139         then
 140                 devname=$(sys2dev "${sysdev}")
 141         fi
 142
 143         if [ -d "${devname}" ]
 144         then
 145                 mount -o bind "${devname}" $mountpoint || continue
 146
 147                 if is_live_path $mountpoint
 148                 then
 149                         echo $mountpoint
 150                         return 0
 151                 else
 152                         umount $mountpoint
 153                 fi
 154         fi
 155
 156         IFS=","
 157         for device in ${devname}
 158         do
 159                 case "$device" in
 160                         *mapper*)
 161                                 # Adding lvm support
 162                                 if [ -x /scripts/local-top/lvm2 ]
 163                                 then
 164                                         ROOT="$device" resume="" /scripts/local-top/lvm2
 165                                 fi
 166                                 ;;
 167
 168                         /dev/md*)
 169                                 # Adding raid support
 170                                 if [ -x /scripts/local-top/mdadm ]
 171                                 then
 172                                         cp /conf/conf.d/md /conf/conf.d/md.orig
 173                                         echo "MD_DEVS=$device " >> /conf/conf.d/md
 174                                         /scripts/local-top/mdadm
 175                                         mv /conf/conf.d/md.orig /conf/conf.d/md
 176                                 fi
 177                                 ;;
 178                 esac
 179         done
 180         unset IFS
 181
 182         [ -n "$device" ] && devname="$device"
 183
 184         [ -e "$devname" ] || continue
 185
 186         if [ -n "${LIVE_MEDIA_OFFSET}" ]
 187         then
 188                 loopdevname=$(setup_loop "${devname}" "loop" "/sys/block/loop*" "${LIVE_MEDIA_OFFSET}" '')
 189                 devname="${loopdevname}"
 190         fi
 191
 192         fstype=$(get_fstype "${devname}")
 193
 194         if is_supported_fs ${fstype}
 195         then
 196                 devuid=$(blkid -o value -s UUID "$devname")
 197                 [ -n "$devuid" ] && grep -qs "\<$devuid\>" /var/lib/live/boot/devices-already-tried-to-mount && continue
 198                 mount -t ${fstype} -o ro,noatime "${devname}" ${mountpoint} || continue
 199                 [ -n "$devuid" ] && echo "$devuid" >> /var/lib/live/boot/devices-already-tried-to-mount
 200
 201                 if [ -n "${FINDISO}" ]
 202                 then
 203                         if [ -f ${mountpoint}/${FINDISO} ]
 204                         then
 205                                 umount ${mountpoint}
 206                                 mkdir -p /live/findiso
 207                                 mount -t ${fstype} -o ro,noatime "${devname}" /live/findiso
 208                                 loopdevname=$(setup_loop "/live/findiso/${FINDISO}" "loop" "/sys/block/loop*" 0 "")
 209                                 devname="${loopdevname}"
 210                                 mount -t iso9660 -o ro,noatime "${devname}" ${mountpoint}
 211                         else
 212                                 umount ${mountpoint}
 213                         fi
 214                 fi
 215
 216                 if is_live_path ${mountpoint} && \
 217                         ([ "${skip_uuid_check}" ] || matches_uuid ${mountpoint})
 218                 then
 219                         echo ${mountpoint}
 220                         return 0
 221                 else
 222                         umount ${mountpoint} 2>/dev/null
 223                 fi
 224         fi
 225
 226         if [ -n "${LIVE_MEDIA_OFFSET}" ]
 227         then
 228                 losetup -d "${loopdevname}"
 229         fi
 230
 231         return 1
 232 }
 233
 234 find_livefs ()
 235 {
 236         timeout="${1}"
 237
 238         # don't start autodetection before timeout has expired
 239         if [ -n "${LIVE_MEDIA_TIMEOUT}" ]
 240         then
 241                 if [ "${timeout}" -lt "${LIVE_MEDIA_TIMEOUT}" ]
 242                 then
 243                         return 1
 244                 fi
 245         fi
 246
 247         # first look at the one specified in the command line
 248         case "${LIVE_MEDIA}" in
 249                 removable-usb)
 250                         for sysblock in $(removable_usb_dev "sys")
 251                         do
 252                                 for dev in $(subdevices "${sysblock}")
 253                                 do
 254                                         if check_dev "${dev}"
 255                                         then
 256                                                 return 0
 257                                         fi
 258                                 done
 259                         done
 260                         return 1
 261                         ;;
 262
 263                 removable)
 264                         for sysblock in $(removable_dev "sys")
 265                         do
 266                                 for dev in $(subdevices "${sysblock}")
 267                                 do
 268                                         if check_dev "${dev}"
 269                                         then
 270                                                 return 0
 271                                         fi
 272                                 done
 273                         done
 274                         return 1
 275                         ;;
 276
 277                 *)
 278                         if [ ! -z "${LIVE_MEDIA}" ]
 279                         then
 280                                 if check_dev "null" "${LIVE_MEDIA}" "skip_uuid_check"
 281                                 then
 282                                         return 0
 283                                 fi
 284                         fi
 285                         ;;
 286         esac
 287
 288         # or do the scan of block devices
 289         # prefer removable devices over non-removable devices, so scan them first
 290         devices_to_scan="$(removable_dev 'sys') $(non_removable_dev 'sys')"
 291
 292         for sysblock in $devices_to_scan
 293         do
 294                 devname=$(sys2dev "${sysblock}")
 295                 [ -e "$devname" ] || continue
 296                 fstype=$(get_fstype "${devname}")
 297
 298                 if /lib/udev/cdrom_id ${devname} > /dev/null
 299                 then
 300                         if check_dev "null" "${devname}"
 301                         then
 302                                 return 0
 303                         fi
 304                 elif is_nice_device "${sysblock}"
 305                 then
 306                         for dev in $(subdevices "${sysblock}")
 307                         do
 308                                 if check_dev "${dev}"
 309                                 then
 310                                         return 0
 311                                 fi
 312                         done
 313                 elif [ "${fstype}" = "squashfs" -o \
 314                         "${fstype}" = "btrfs" -o \
 315                         "${fstype}" = "ext2" -o \
 316                         "${fstype}" = "ext3" -o \
 317                         "${fstype}" = "ext4" -o \
 318                         "${fstype}" = "jffs2" ]
 319                 then
 320                         # This is an ugly hack situation, the block device has
 321                         # an image directly on it.  It's hopefully
 322                         # live-boot, so take it and run with it.
 323                         ln -s "${devname}" "${devname}.${fstype}"
 324                         echo "${devname}.${fstype}"
 325                         return 0
 326                 fi
 327         done
 328
 329         return 1
 330 }
 331
 332 is_in_list_separator_helper ()
 333 {
 334         local sep element list
 335         sep=${1}
 336         shift
 337         element=${1}
 338         shift
 339         list=${*}
 340         echo ${list} | grep -qe "^\(.*${sep}\)\?${element}\(${sep}.*\)\?$"
 341 }
 342
 343 is_in_space_sep_list ()
 344 {
 345         local element
 346         element=${1}
 347         shift
 348         is_in_list_separator_helper "[[:space:]]" "${element}" "${*}"
 349 }
 350
 351 is_in_comma_sep_list ()
 352 {
 353         local element
 354         element=${1}
 355         shift
 356         is_in_list_separator_helper "," "${element}" "${*}"
 357 }
 358
 359 sys2dev ()
 360 {
 361         sysdev=${1#/sys}
 362         echo "/dev/$(udevadm info -q name -p ${sysdev} 2>/dev/null|| echo ${sysdev##*/})"
 363 }
 364
 365 subdevices ()
 366 {
 367         sysblock=${1}
 368         r=""
 369
 370         for dev in "${sysblock}"/* "${sysblock}"
 371         do
 372                 if [ -e "${dev}/dev" ]
 373                 then
 374                         r="${r} ${dev}"
 375                 fi
 376         done
 377
 378         echo ${r}
 379 }
 380
 381 storage_devices()
 382 {
 383         black_listed_devices="${1}"
 384         white_listed_devices="${2}"
 385
 386         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "loop|ram|fd")
 387         do
 388                 fulldevname=$(sys2dev "${sysblock}")
 389
 390                 if is_in_space_sep_list ${fulldevname} ${black_listed_devices} || \
 391                         [ -n "${white_listed_devices}" ] && \
 392                         ! is_in_space_sep_list ${fulldevname} ${white_listed_devices}
 393                 then
 394                         # skip this device entirely
 395                         continue
 396                 fi
 397
 398                 for dev in $(subdevices "${sysblock}")
 399                 do
 400                         devname=$(sys2dev "${dev}")
 401
 402                         if is_in_space_sep_list ${devname} ${black_listed_devices}
 403                         then
 404                                 # skip this subdevice
 405                                 continue
 406                         else
 407                                 echo "${devname}"
 408                         fi
 409                 done
 410         done
 411 }
 412
 413 is_supported_fs ()
 414 {
 415         fstype="${1}"
 416
 417         # Validate input first
 418         if [ -z "${fstype}" ]
 419         then
 420                 return 1
 421         fi
 422
 423         # Try to look if it is already supported by the kernel
 424         if grep -q ${fstype} /proc/filesystems
 425         then
 426                 return 0
 427         else
 428                 # Then try to add support for it the gentle way using the initramfs capabilities
 429                 modprobe ${fstype}
 430                 if grep -q ${fstype} /proc/filesystems
 431                 then
 432                         return 0
 433                 # Then try the hard way if /root is already reachable
 434                 else
 435                         kmodule="/root/lib/modules/`uname -r`/${fstype}/${fstype}.ko"
 436                         if [ -e "${kmodule}" ]
 437                         then
 438                                 insmod "${kmodule}"
 439                                 if grep -q ${fstype} /proc/filesystems
 440                                 then
 441                                         return 0
 442                                 fi
 443                         fi
 444                 fi
 445         fi
 446
 447         return 1
 448 }
 449
 450 get_fstype ()
 451 {
 452         /sbin/blkid -s TYPE -o value $1 2>/dev/null
 453 }
 454
 455 where_is_mounted ()
 456 {
 457         device=${1}
 458         # return first found
 459         grep -m1 "^${device} " /proc/mounts | cut -f2 -d ' '
 460 }
 461
 462 trim_path ()
 463 {
 464         # remove all unnecessary /:s in the path, including last one (except
 465         # if path is just "/")
 466         echo ${1} | sed 's|//\+|/|g' | sed 's|^\(.*[^/]\)/$|\1|'
 467 }
 468
 469 what_is_mounted_on ()
 470 {
 471         local dir
 472         dir="$(trim_path ${1})"
 473         grep -m1 "^[^ ]\+ ${dir} " /proc/mounts | cut -d' ' -f1
 474 }
 475
 476 chown_ref ()
 477 {
 478         local reference targets owner
 479         reference="${1}"
 480         shift
 481         targets=${@}
 482         owner=$(stat -c %u:%g "${reference}")
 483         chown -h ${owner} ${targets}
 484 }
 485
 486 chmod_ref ()
 487 {
 488         local reference targets rights
 489         reference="${1}"
 490         shift
 491         targets=${@}
 492         rights=$(stat -c %a "${reference}")
 493         chmod ${rights} ${targets}
 494 }
 495
 496 lastline ()
 497 {
 498         while read lines
 499         do
 500                 line=${lines}
 501         done
 502
 503         echo "${line}"
 504 }
 505
 506 base_path ()
 507 {
 508         testpath="${1}"
 509         mounts="$(awk '{print $2}' /proc/mounts)"
 510         testpath="$(busybox realpath ${testpath})"
 511
 512         while true
 513         do
 514                 if echo "${mounts}" | grep -qs "^${testpath}"
 515                 then
 516                         set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
 517                         echo ${1}
 518                         break
 519                 else
 520                         testpath=$(dirname $testpath)
 521                 fi
 522         done
 523 }
 524
 525 fs_size ()
 526 {
 527         # Returns used/free fs kbytes + 5% more
 528         # You could pass a block device as ${1} or the mount point as ${2}
 529
 530         dev="${1}"
 531         mountp="${2}"
 532         used="${3}"
 533
 534         if [ -z "${mountp}" ]
 535         then
 536                 mountp="$(where_is_mounted ${dev})"
 537
 538                 if [ -z "${mountp}" ]
 539                 then
 540                         mountp="/mnt/tmp_fs_size"
 541
 542                         mkdir -p "${mountp}"
 543                         mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}" || log_warning_msg "cannot mount -t $(get_fstype ${dev}) -o ro ${dev} ${mountp}"
 544
 545                         doumount=1
 546                 fi
 547         fi
 548
 549         if [ "${used}" = "used" ]
 550         then
 551                 size=$(du -ks ${mountp} | cut -f1)
 552                 size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
 553         else
 554                 # free space
 555                 size="$(df -kP | grep -s ${mountp} | awk '{print $4}')"
 556         fi
 557
 558         if [ -n "${doumount}" ]
 559         then
 560                 umount "${mountp}" || log_warning_msg "cannot umount ${mountp}"
 561                 rmdir "${mountp}"
 562         fi
 563
 564         echo "${size}"
 565 }
 566
 567 load_keymap ()
 568 {
 569         # Load custom keymap
 570         if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
 571         then
 572                 loadkeys --quiet /etc/boottime.kmap.gz
 573         fi
 574 }
 575
 576 setup_loop ()
 577 {
 578         local fspath module pattern offset encryption readonly
 579         fspath=${1}
 580         module=${2}
 581         pattern=${3}
 582         offset=${4}
 583         encryption=${5}
 584         readonly=${6}
 585
 586         # the output of setup_loop is evaluated in other functions,
 587         # modprobe leaks kernel options like "libata.dma=0"
 588         # as "options libata dma=0" on stdout, causing serious
 589         # problems therefor, so instead always avoid output to stdout
 590         modprobe -q -b "${module}" 1>/dev/null
 591
 592         udevadm settle
 593
 594         for loopdev in ${pattern}
 595         do
 596                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 597                 then
 598                         dev=$(sys2dev "${loopdev}")
 599                         options=''
 600
 601                         if [ -n "${readonly}" ]
 602                         then
 603                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 604                                 then
 605                                         options="${options} -r"
 606                                 fi
 607                         fi
 608
 609                         if [ -n "${offset}" ] && [ 0 -lt "${offset}" ]
 610                         then
 611                                 options="${options} -o ${offset}"
 612                         fi
 613
 614                         if [ -z "${encryption}" ]
 615                         then
 616                                 losetup ${options} "${dev}" "${fspath}"
 617                         else
 618                                 # Loop AES encryption
 619                                 while true
 620                                 do
 621                                         load_keymap
 622
 623                                         echo -n "Enter passphrase for root filesystem: " >&6
 624                                         read -s passphrase
 625                                         echo "${passphrase}" > /tmp/passphrase
 626                                         unset passphrase
 627                                         exec 9</tmp/passphrase
 628                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 629                                         error=${?}
 630                                         exec 9<&-
 631                                         rm -f /tmp/passphrase
 632
 633                                         if [ 0 -eq ${error} ]
 634                                         then
 635                                                 unset error
 636                                                 break
 637                                         fi
 638
 639                                         echo
 640                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 641                                         read answer
 642
 643                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 644                                         then
 645                                                 unset answer
 646                                                 break
 647                                         fi
 648                                 done
 649                         fi
 650
 651                         echo "${dev}"
 652                         return 0
 653                 fi
 654         done
 655
 656         panic "No loop devices available"
 657 }
 658
 659 try_mount ()
 660 {
 661         dev="${1}"
 662         mountp="${2}"
 663         opts="${3}"
 664         fstype="${4}"
 665
 666         old_mountp="$(where_is_mounted ${dev})"
 667
 668         if [ -n "${old_mountp}" ]
 669         then
 670                 if [ "${opts}" != "ro" ]
 671                 then
 672                         mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
 673                 fi
 674
 675                 mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
 676         else
 677                 if [ -z "${fstype}" ]
 678                 then
 679                         fstype=$(get_fstype "${dev}")
 680                 fi
 681                 mount -t "${fstype}" -o "${opts}" "${dev}" "${mountp}" || \
 682                 ( echo "SKIPPING: Cannot mount ${dev} on ${mountp}, fstype=${fstype}, options=${opts}" > boot.log && return 0 )
 683         fi
 684 }
 685
 686 # Try to mount $device to the place expected by live-boot. If $device
 687 # is already mounted somewhere, move it to the expected place. If
 688 # we're only probing $device (to check if it has custom persistence)
 689 # $probe should be set, which suppresses warnings upon failure. On
 690 # success, print the mount point for $device.
 691 mount_persistence_media ()
 692 {
 693         local device probe backing old_backing fstype mount_opts
 694         device=${1}
 695         probe=${2}
 696
 697         if [ ! -b "${device}" ]
 698         then
 699                 return 1
 700         fi
 701
 702         backing="/live/persistence/$(basename ${device})"
 703
 704         mkdir -p "${backing}"
 705         old_backing="$(where_is_mounted ${device})"
 706         if [ -z "${old_backing}" ]
 707         then
 708                 fstype="$(get_fstype ${device})"
 709                 mount_opts="rw,noatime"
 710                 if [ -n "${PERSISTENCE_READONLY}" ]
 711                 then
 712                         mount_opts="ro,noatime"
 713                 fi
 714                 if mount -t "${fstype}" -o "${mount_opts}" "${device}" "${backing}" >/dev/null
 715                 then
 716                         echo ${backing}
 717                         return 0
 718                 else
 719                         [ -z "${probe}" ] && log_warning_msg "Failed to mount persistence media ${device}"
 720                         rmdir "${backing}"
 721                         return 1
 722                 fi
 723         elif [ "${backing}" != "${old_backing}" ]
 724         then
 725                 if ! mount --move ${old_backing} ${backing} >/dev/null
 726                 then
 727                         [ -z "${probe}" ] && log_warning_msg "Failed to move persistence media ${device}"
 728                         rmdir "${backing}"
 729                         return 1
 730                 fi
 731                 mount_opts="rw,noatime"
 732                 if [ -n "${PERSISTENCE_READONLY}" ]
 733                 then
 734                         mount_opts="ro,noatime"
 735                 fi
 736                 if ! mount -o "remount,${mount_opts}" "${backing}" >/dev/null
 737                 then
 738                         log_warning_msg "Failed to remount persistence media ${device} writable"
 739                         # Don't unmount or rmdir the new mountpoint in this case
 740                 fi
 741                 echo ${backing}
 742                 return 0
 743         else
 744                 # This means that $device has already been mounted on
 745                 # the place expected by live-boot, so we're done.
 746                 echo ${backing}
 747                 return 0
 748         fi
 749 }
 750
 751 close_persistence_media ()
 752 {
 753         local device backing
 754         device=${1}
 755         backing="$(where_is_mounted ${device})"
 756
 757         if [ -d "${backing}" ]
 758         then
 759                 umount "${backing}" >/dev/null 2>&1
 760                 rmdir "${backing}" >/dev/null 2>&1
 761         fi
 762
 763         if is_active_luks_mapping ${device}
 764         then
 765                 /sbin/cryptsetup luksClose ${device}
 766         fi
 767 }
 768
 769 open_luks_device ()
 770 {
 771         dev="${1}"
 772         name="$(basename ${dev})"
 773         opts="--key-file=-"
 774         if [ -n "${PERSISTENCE_READONLY}" ]
 775         then
 776                 opts="${opts} --readonly"
 777         fi
 778
 779         if /sbin/cryptsetup status "${name}" >/dev/null 2>&1
 780         then
 781                 re="^[[:space:]]*device:[[:space:]]*\([^[:space:]]*\)$"
 782                 opened_dev=$(cryptsetup status ${name} 2>/dev/null | grep "${re}" | sed "s|${re}|\1|")
 783                 if [ "${opened_dev}" = "${dev}" ]
 784                 then
 785                         luks_device="/dev/mapper/${name}"
 786                         echo ${luks_device}
 787                         return 0
 788                 else
 789                         log_warning_msg "Cannot open luks device ${dev} since ${opened_dev} already is opened with its name"
 790                         return 1
 791                 fi
 792         fi
 793
 794         load_keymap
 795
 796         while true
 797         do
 798                 /lib/cryptsetup/askpass "Enter passphrase for ${dev}: " | \
 799                         /sbin/cryptsetup -T 1 luksOpen ${dev} ${name} ${opts}
 800
 801                 if [ 0 -eq ${?} ]
 802                 then
 803                         luks_device="/dev/mapper/${name}"
 804                         echo ${luks_device}
 805                         return 0
 806                 fi
 807
 808                 echo >&6
 809                 echo -n "There was an error decrypting ${dev} ... Retry? [Y/n] " >&6
 810                 read answer
 811
 812                 if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 813                 then
 814                         return 2
 815                 fi
 816         done
 817 }
 818
 819 get_gpt_name ()
 820 {
 821     local dev
 822     dev="${1}"
 823     /sbin/blkid -s PART_ENTRY_NAME -p -o value ${dev} 2>/dev/null
 824 }
 825
 826 is_gpt_device ()
 827 {
 828     local dev
 829     dev="${1}"
 830     [ "$(/sbin/blkid -s PART_ENTRY_SCHEME -p -o value ${dev} 2>/dev/null)" = "gpt" ]
 831 }
 832
 833 probe_for_gpt_name ()
 834 {
 835         local overlays dev gpt_dev gpt_name
 836         overlays="${1}"
 837         dev="${2}"
 838
 839         gpt_dev="${dev}"
 840         if is_active_luks_mapping ${dev}
 841         then
 842                 # if $dev is an opened luks device, we need to check
 843                 # GPT stuff on the backing device
 844                 gpt_dev=$(get_luks_backing_device "${dev}")
 845         fi
 846
 847         if ! is_gpt_device ${gpt_dev}
 848         then
 849                 return
 850         fi
 851
 852         gpt_name=$(get_gpt_name ${gpt_dev})
 853         for label in ${overlays}
 854         do
 855                 if [ "${gpt_name}" = "${label}" ]
 856                 then
 857                         echo "${label}=${dev}"
 858                 fi
 859         done
 860 }
 861
 862 probe_for_fs_label ()
 863 {
 864         local overlays dev
 865         overlays="${1}"
 866         dev="${2}"
 867
 868         for label in ${overlays}
 869         do
 870                 if [ "$(/sbin/blkid -s LABEL -o value $dev 2>/dev/null)" = "${label}" ]
 871                 then
 872                         echo "${label}=${dev}"
 873                 fi
 874         done
 875 }
 876
 877 probe_for_file_name ()
 878 {
 879         local overlays dev ret backing
 880         overlays="${1}"
 881         dev="${2}"
 882
 883         ret=""
 884         backing="$(mount_persistence_media ${dev} probe)"
 885         if [ -z "${backing}" ]
 886         then
 887             return
 888         fi
 889
 890         for label in ${overlays}
 891         do
 892                 path=${backing}/${PERSISTENCE_PATH}/${label}
 893                 if [ -f "${path}" ]
 894                 then
 895                         local loopdev
 896                         loopdev=$(setup_loop "${path}" "loop" "/sys/block/loop*")
 897                         ret="${ret} ${label}=${loopdev}"
 898                 fi
 899         done
 900
 901         if [ -n "${ret}" ]
 902         then
 903                 echo ${ret}
 904         else
 905                 # unmount and remove mountpoint
 906                 umount ${backing} > /dev/null 2>&1 || true
 907                 rmdir ${backing} > /dev/null 2>&1 || true
 908         fi
 909 }
 910
 911 find_persistence_media ()
 912 {
 913         # Scans devices for overlays, and returns a whitespace
 914         # separated list of how to use them. Only overlays with a partition
 915         # label or file name in ${overlays} are returned.
 916         #
 917         # When scanning a LUKS device, the user will be asked to enter the
 918         # passphrase; on failure to enter it, or if no persistence partitions
 919         # or files were found, the LUKS device is closed.
 920         #
 921         # For all other cases (overlay partition and overlay file) the
 922         # return value is "${label}=${device}", where ${device} a device that
 923         # can mount the content. In the case of an overlay file, the device
 924         # containing the file will remain mounted as a side-effect.
 925         #
 926         # No devices in ${black_listed_devices} will be scanned, and if
 927         # ${white_list_devices} is non-empty, only devices in it will be
 928         # scanned.
 929
 930         local overlays white_listed_devices ret black_listed_devices
 931         overlays="${1}"
 932         white_listed_devices="${2}"
 933         ret=""
 934
 935         #
 936         # The devices that are hosting the actual live rootfs should not be
 937         # used for persistence storage since otherwise you might mount a
 938         # parent directory on top of a sub-directory of the same filesystem
 939         # in one union together.
 940         #
 941         black_listed_devices=""
 942         for d in /live/rootfs/* /live/findiso /live/fromiso
 943         do
 944                 black_listed_devices="${black_listed_devices} $(what_is_mounted_on d)"
 945         done
 946
 947         for dev in $(storage_devices "${black_listed_devices}" "${white_listed_devices}")
 948         do
 949                 local result luks_device
 950                 result=""
 951
 952                 luks_device=""
 953                 # Check if it's a luks device; we'll have to open the device
 954                 # in order to probe any filesystem it contains, like we do
 955                 # below. activate_custom_mounts() also depends on that any luks
 956                 # device already has been opened.
 957                 if is_in_comma_sep_list luks ${PERSISTENCE_ENCRYPTION} && is_luks_partition ${dev}
 958                 then
 959                         if luks_device=$(open_luks_device "${dev}")
 960                         then
 961                                 dev="${luks_device}"
 962                         else
 963                                 # skip $dev since we failed/chose not to open it
 964                                 continue
 965                         fi
 966                 elif ! is_in_comma_sep_list none ${PERSISTENCE_ENCRYPTION}
 967                 then
 968                         # skip $dev since we don't allow unencrypted storage
 969                         continue
 970                 fi
 971
 972                 # Probe for matching GPT partition names or filesystem labels
 973                 if is_in_comma_sep_list filesystem ${PERSISTENCE_STORAGE}
 974                 then
 975                         result=$(probe_for_gpt_name "${overlays}" ${dev})
 976                         if [ -n "${result}" ]
 977                         then
 978                                 ret="${ret} ${result}"
 979                                 continue
 980                         fi
 981
 982                         result=$(probe_for_fs_label "${overlays}" ${dev})
 983                         if [ -n "${result}" ]
 984                         then
 985                                 ret="${ret} ${result}"
 986                                 continue
 987                         fi
 988                 fi
 989
 990                 # Probe for files with matching name on mounted partition
 991                 if is_in_comma_sep_list file ${PERSISTENCE_STORAGE}
 992                 then
 993                         result=$(probe_for_file_name "${overlays}" ${dev})
 994                         if [ -n "${result}" ]
 995                         then
 996                                 local loopdevice
 997                                 loopdevice=${result##*=}
 998                                 if is_in_comma_sep_list luks ${PERSISTENCE_ENCRYPTION} && is_luks_partition ${loopdevice}
 999                                 then
1000                                         local luksfile
1001                                         luksfile=""
1002                                         if luksfile=$(open_luks_device "${loopdevice}")
1003                                         then
1004                                                 result=${result%%=*}
1005                                                 result="${result}=${luksfile}"
1006                                         else
1007                                                 losetup -d $loopdevice
1008                                                 result=""
1009                                         fi
1010                                 fi
1011                                 ret="${ret} ${result}"
1012                                 continue
1013                         fi
1014                 fi
1015
1016                 # Close luks device if it isn't used
1017                 if [ -z "${result}" ] && [ -n "${luks_device}" ] && is_active_luks_mapping "${luks_device}"
1018                 then
1019                         /sbin/cryptsetup luksClose "${luks_device}"
1020                 fi
1021         done
1022
1023         if [ -n "${ret}" ]
1024         then
1025                 echo ${ret}
1026         fi
1027 }
1028
1029 get_mac ()
1030 {
1031         mac=""
1032
1033         for adaptor in /sys/class/net/*
1034         do
1035                 status="$(cat ${adaptor}/iflink)"
1036
1037                 if [ "${status}" -eq 2 ]
1038                 then
1039                         mac="$(cat ${adaptor}/address)"
1040                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
1041                 fi
1042         done
1043
1044         echo ${mac}
1045 }
1046
1047 is_luks_partition ()
1048 {
1049         device="${1}"
1050         /sbin/cryptsetup isLuks "${device}" 1>/dev/null 2>&1
1051 }
1052
1053 is_active_luks_mapping ()
1054 {
1055         device="${1}"
1056         /sbin/cryptsetup status "${device}" 1>/dev/null 2>&1
1057 }
1058
1059 get_luks_backing_device ()
1060 {
1061         device=${1}
1062         cryptsetup status ${device} 2> /dev/null | \
1063                 awk '{if ($1 == "device:") print $2}'
1064 }
1065
1066 removable_dev ()
1067 {
1068         output_format="${1}"
1069         want_usb="${2}"
1070         ret=
1071
1072         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
1073         do
1074                 dev_ok=
1075                 if [ "$(cat ${sysblock}/removable)" = "1" ]
1076                 then
1077                         if [ -z "${want_usb}" ]
1078                         then
1079                                 dev_ok="true"
1080                         else
1081                                 if readlink ${sysblock} | grep -q usb
1082                                 then
1083                                         dev_ok="true"
1084                                 fi
1085                         fi
1086                 fi
1087
1088                 if [ "${dev_ok}" = "true" ]
1089                 then
1090                         case "${output_format}" in
1091                                 sys)
1092                                         ret="${ret} ${sysblock}"
1093                                         ;;
1094                                 *)
1095                                         devname=$(sys2dev "${sysblock}")
1096                                         ret="${ret} ${devname}"
1097                                         ;;
1098                         esac
1099                 fi
1100         done
1101
1102         echo "${ret}"
1103 }
1104
1105 removable_usb_dev ()
1106 {
1107         output_format="${1}"
1108
1109         removable_dev "${output_format}" "want_usb"
1110 }
1111
1112 non_removable_dev ()
1113 {
1114         output_format="${1}"
1115         ret=
1116
1117         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
1118         do
1119                 if [ "$(cat ${sysblock}/removable)" = "0" ]
1120                 then
1121                         case "${output_format}" in
1122                                 sys)
1123                                         ret="${ret} ${sysblock}"
1124                                         ;;
1125                                 *)
1126                                         devname=$(sys2dev "${sysblock}")
1127                                         ret="${ret} ${devname}"
1128                                         ;;
1129                         esac
1130                 fi
1131         done
1132
1133         echo "${ret}"
1134 }
1135
1136 link_files ()
1137 {
1138         # create source's directory structure in dest, and recursively
1139         # create symlinks in dest to to all files in source. if mask
1140         # is non-empty, remove mask from all source paths when
1141         # creating links (will be necessary if we change root, which
1142         # live-boot normally does (into $rootmnt)).
1143         local src_dir dest_dir src_transform
1144
1145         # remove multiple /:s and ensure ending on /
1146         src_dir="$(trim_path ${1})/"
1147         dest_dir="$(trim_path ${2})/"
1148         src_transform="${3}"
1149
1150         # This check can only trigger on the inital, non-recursive call since
1151         # we create the destination before recursive calls
1152         if [ ! -d "${dest_dir}" ]
1153         then
1154                 log_warning_msg "Must link_files into a directory"
1155                 return
1156         fi
1157
1158         find "${src_dir}" -mindepth 1 -maxdepth 1 | \
1159         while read src
1160         do
1161                 local dest final_src
1162                 dest="${dest_dir}$(basename "${src}")"
1163                 if [ -d "${src}" ]
1164                 then
1165                         if [ -z "$(ls -A "${src}")" ]
1166                         then
1167                                 continue
1168                         fi
1169                         if [ ! -d "${dest}" ]
1170                         then
1171                                 mkdir -p "${dest}"
1172                                 chown_ref "${src}" "${dest}"
1173                                 chmod_ref "${src}" "${dest}"
1174                         fi
1175                         link_files "${src}" "${dest}" "${src_transform}"
1176                 else
1177                         final_src=${src}
1178                         if [ -n "${src_transform}" ]
1179                         then
1180                                 final_src="$(echo ${final_src} | sed "${src_transform}")"
1181                         fi
1182                         rm -rf "${dest}" 2> /dev/null
1183                         ln -s "${final_src}" "${dest}"
1184                         chown_ref "${src}" "${dest}"
1185                 fi
1186         done
1187 }
1188
1189 do_union ()
1190 {
1191         local unionmountpoint unionrw unionro
1192         unionmountpoint="${1}"  # directory where the union is mounted
1193         shift
1194         unionrw="${1}"          # branch where the union changes are stored
1195         shift
1196         unionro="${*}"          # space separated list of read-only branches (optional)
1197
1198         case "${UNIONTYPE}" in
1199                 aufs)
1200                         rw_opt="rw"
1201                         ro_opt="rr+wh"
1202                         noxino_opt="noxino"
1203                         ;;
1204
1205                 unionfs-fuse)
1206                         rw_opt="RW"
1207                         ro_opt="RO"
1208                         ;;
1209
1210                 *)
1211                         rw_opt="rw"
1212                         ro_opt="ro"
1213                         ;;
1214         esac
1215
1216         case "${UNIONTYPE}" in
1217                 unionfs-fuse)
1218                         unionmountopts="-o cow -o noinitgroups -o default_permissions -o allow_other -o use_ino -o suid"
1219                         unionmountopts="${unionmountopts} ${unionrw}=${rw_opt}"
1220                         if [ -n "${unionro}" ]
1221                         then
1222                                 for rofs in ${unionro}
1223                                 do
1224                                         unionmountopts="${unionmountopts}:${rofs}=${ro_opt}"
1225                                 done
1226                         fi
1227                         ( sysctl -w fs.file-max=391524 ; ulimit -HSn 16384
1228                         unionfs-fuse ${unionmountopts} "${unionmountpoint}" ) && \
1229                         ( mkdir -p /run/sendsigs.omit.d
1230                         pidof unionfs-fuse >> /run/sendsigs.omit.d/unionfs-fuse || true )
1231                         ;;
1232
1233                 overlayfs)
1234                         # XXX: can multiple unionro be used? (overlayfs only handles two dirs, but perhaps they can be chained?)
1235                         # XXX: and can unionro be optional? i.e. can overlayfs skip lowerdir?
1236                         if echo ${unionro} | grep -q " "
1237                         then
1238                                 panic "Multiple lower filesystems are currently not supported with overlayfs (unionro = ${unionro})."
1239                         elif [ -z "${unionro}"  ]
1240                         then
1241                                 panic "Overlayfs needs at least one lower filesystem (read-only branch)."
1242                         fi
1243                         unionmountopts="-o noatime,lowerdir=${unionro},upperdir=${unionrw}"
1244                         mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
1245                         ;;
1246
1247                 *)
1248                         unionmountopts="-o noatime,${noxino_opt},dirs=${unionrw}=${rw_opt}"
1249                         if [ -n "${unionro}" ]
1250                         then
1251                                 for rofs in ${unionro}
1252                                 do
1253                                         unionmountopts="${unionmountopts}:${rofs}=${ro_opt}"
1254                                 done
1255                         fi
1256                         mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
1257                         ;;
1258         esac
1259 }
1260
1261 get_custom_mounts ()
1262 {
1263         # Side-effect: leaves $devices with persistence.conf mounted in /live/persistence
1264         # Side-effect: prints info to file $custom_mounts
1265
1266         local custom_mounts devices bindings links
1267         custom_mounts=${1}
1268         shift
1269         devices=${@}
1270
1271         bindings="/tmp/bindings.list"
1272         links="/tmp/links.list"
1273         rm -rf ${bindings} ${links} 2> /dev/null
1274
1275         for device in ${devices}
1276         do
1277                 local device_name backing include_list
1278                 device_name="$(basename ${device})"
1279                 backing=$(mount_persistence_media ${device})
1280                 if [ -z "${backing}" ]
1281                 then
1282                         continue
1283                 fi
1284
1285                 if [ -r "${backing}/${persistence_list}" ]
1286                 then
1287                         include_list="${backing}/${persistence_list}"
1288                 else
1289                         continue
1290                 fi
1291
1292                 if [ -n "${LIVE_BOOT_DEBUG}" ] && [ -e "${include_list}" ]
1293                 then
1294                         cp ${include_list} /live/persistence/${persistence_list}.${device_name}
1295                 fi
1296
1297                 while read dir options # < ${include_list}
1298                 do
1299                         if echo ${dir} | grep -qe "^[[:space:]]*\(#.*\)\?$"
1300                         then
1301                                 # skipping empty or commented lines
1302                                 continue
1303                         fi
1304
1305                         if trim_path ${dir} | grep -q -e "^[^/]" -e "^/lib" -e "^/lib/live\(/.*\)\?$" -e "^/\(.*/\)\?\.\.\?\(/.*\)\?$"
1306                         then
1307                                 log_warning_msg "Skipping unsafe custom mount ${dir}: must be an absolute path containing neither the \".\" nor \"..\" special dirs, and cannot be \"/lib\", or \"/lib/live\" or any of its sub-directories."
1308                                 continue
1309                         fi
1310
1311                         local opt_source opt_link source full_source full_dest
1312                         opt_source=""
1313                         opt_link=""
1314                         for opt in $(echo ${options} | tr ',' ' ');
1315                         do
1316                                 case "${opt}" in
1317                                         source=*)
1318                                                 opt_source=${opt#source=}
1319                                                 ;;
1320                                         link)
1321                                                 opt_link="true"
1322                                                 ;;
1323                                         union|bind)
1324                                                 ;;
1325                                         *)
1326                                                 log_warning_msg "Skipping custom mount with unkown option: ${opt}"
1327                                                 continue 2
1328                                                 ;;
1329                                 esac
1330                         done
1331
1332                         source="${dir}"
1333                         if [ -n "${opt_source}" ]
1334                         then
1335                                 if echo ${opt_source} | grep -q -e "^/" -e "^\(.*/\)\?\.\.\?\(/.*\)\?$" && [ "${opt_source}" != "." ]
1336                                 then
1337                                         log_warning_msg "Skipping unsafe custom mount with option source=${opt_source}: must be either \".\" (the media root) or a relative path w.r.t. the media root that contains neither comas, nor the special \".\" and \"..\" path components"
1338                                         continue
1339                                 else
1340                                         source="${opt_source}"
1341                                 fi
1342                         fi
1343
1344                         full_source="$(trim_path ${backing}/${source})"
1345                         full_dest="$(trim_path ${rootmnt}/${dir})"
1346                         if [ -n "${opt_link}" ]
1347                         then
1348                                 echo "${device} ${full_source} ${full_dest} ${options}" >> ${links}
1349                         else
1350                                 echo "${device} ${full_source} ${full_dest} ${options}" >> ${bindings}
1351                         fi
1352                 done < ${include_list}
1353         done
1354
1355         # We sort the list according to destination so we're sure that
1356         # we won't hide a previous mount. We also ignore duplicate
1357         # destinations in a more or less arbitrary way.
1358         [ -e "${bindings}" ] && sort -k3 -sbu ${bindings} >> ${custom_mounts} && rm ${bindings}
1359
1360         # After all mounts are considered we add symlinks so they
1361         # won't be hidden by some mount.
1362         [ -e "${links}" ] && cat ${links} >> ${custom_mounts} && rm ${links}
1363
1364         # We need to make sure that no two custom mounts have the same sources
1365         # or are nested; if that is the case, too much weird stuff can happen.
1366         local prev_source prev_dest
1367         prev_source="impossible source" # first iteration must not match
1368         prev_dest=""
1369         # This sort will ensure that a source /a comes right before a source
1370         # /a/b so we only need to look at the previous source
1371         sort -k2 -b ${custom_mounts} |
1372         while read device source dest options
1373         do
1374                 if echo ${source} | grep -qe "^${prev_source}\(/.*\)\?$"
1375                 then
1376                         panic "Two persistence mounts have the same or nested sources: ${source} on ${dest}, and ${prev_source} on ${prev_dest}"
1377                 fi
1378                 prev_source=${source}
1379                 prev_dest=${dest}
1380         done
1381 }
1382
1383 activate_custom_mounts ()
1384 {
1385         local custom_mounts used_devices
1386         custom_mounts="${1}" # the ouput from get_custom_mounts()
1387         used_devices=""
1388
1389         while read device source dest options # < ${custom_mounts}
1390         do
1391                 local opt_bind opt_link opt_union
1392                 opt_bind="true"
1393                 opt_link=""
1394                 opt_union=""
1395                 for opt in $(echo ${options} | tr ',' ' ');
1396                 do
1397                         case "${opt}" in
1398                                 bind)
1399                                         opt_bind="true"
1400                                         unset opt_link opt_union
1401                                         ;;
1402                                 link)
1403                                         opt_link="true"
1404                                         unset opt_bind opt_union
1405                                         ;;
1406                                 union)
1407                                         opt_union="true"
1408                                         unset opt_bind opt_link
1409                                         ;;
1410                         esac
1411                 done
1412
1413                 if [ -n "$(what_is_mounted_on "${dest}")" ]
1414                 then
1415                         if [ "${dest}" = "${rootmnt}" ]
1416                         then
1417                                 umount "${dest}"
1418                         else
1419                                 log_warning_msg "Skipping custom mount ${dest}: $(what_is_mounted_on "${dest}") is already mounted there"
1420                                 continue
1421                         fi
1422                 fi
1423
1424                 if [ ! -d "${dest}" ]
1425                 then
1426                         # create the destination and delete existing files in
1427                         # its path that are in the way
1428                         path="/"
1429                         for dir in $(echo ${dest} | sed -e 's|/\+| |g')
1430                         do
1431                                 path=$(trim_path ${path}/${dir})
1432                                 if [ -f ${path} ]
1433                                 then
1434                                         rm -f ${path}
1435                                 fi
1436                                 if [ ! -e ${path} ]
1437                                 then
1438                                         mkdir -p ${path}
1439                                         if echo ${path} | grep -qe "^${rootmnt}/*home/[^/]\+"
1440                                         then
1441                                                 # if ${dest} is in /home try fixing proper ownership by assuming that the intended user is the first, which is usually the case
1442                                                 # FIXME: this should really be handled by live-config since we don't know for sure which uid a certain user has until then
1443                                                 chown 1000:1000 ${path}
1444                                         fi
1445                                 fi
1446                         done
1447                 fi
1448
1449                 # if ${source} doesn't exist on our persistence media
1450                 # we bootstrap it with $dest from the live filesystem.
1451                 # this both makes sense and is critical if we're
1452                 # dealing with /etc or other system dir.
1453                 if [ ! -d "${source}" ]
1454                 then
1455                         if [ -n "${PERSISTENCE_READONLY}" ]
1456                         then
1457                                 continue
1458                         elif [ -n "${opt_union}" ] || [ -n "${opt_link}" ]
1459                         then
1460                                 # unions and don't need to be bootstrapped
1461                                 # link dirs can't be bootstrapped in a sensible way
1462                                 mkdir -p "${source}"
1463                                 chown_ref "${dest}" "${source}"
1464                                 chmod_ref "${dest}" "${source}"
1465                         elif [ -n "${opt_bind}" ]
1466                         then
1467                                 # ensure that $dest is not copied *into* $source
1468                                 mkdir -p "$(dirname ${source})"
1469                                 cp -a "${dest}" "${source}"
1470                         fi
1471                 fi
1472
1473                 # XXX: If CONFIG_AUFS_ROBR is added to the Debian kernel we can
1474                 # ignore the loop below and set rootfs_dest_backing=$dest
1475                 local rootfs_dest_backing
1476                 rootfs_dest_backing=""
1477                 if [ -n "${opt_link}" ] || [ -n "${opt_union}" ]
1478                 then
1479                         for d in /live/rootfs/*
1480                         do
1481                                 if [ -n "${rootmnt}" ]
1482                                 then
1483                                         fs="${d}/$(echo ${dest} | sed -e "s|${rootmnt}||")"
1484                                 else
1485                                         fs="${d}/${dest}"
1486                                 fi
1487                                 if [ -d "${fs}" ]
1488                                 then
1489                                         rootfs_dest_backing="${rootfs_dest_backing} ${fs}"
1490                                 fi
1491                         done
1492                 fi
1493
1494                 local cow_dir links_source
1495                 if [ -n "${opt_link}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1496                 then
1497                         link_files ${source} ${dest} "s|^/live/|/lib/live/mount/|"
1498                 elif [ -n "${opt_link}" ] && [ -n "${PERSISTENCE_READONLY}" ]
1499                 then
1500                         mkdir -p ${rootmnt}/lib/live/mount/persistence
1501                         links_source=$(mktemp -d ${rootmnt}/lib/live/mount/persistence/links-source-XXXXXX)
1502                         chown_ref ${source} ${links_source}
1503                         chmod_ref ${source} ${links_source}
1504                         # We put the cow dir in the below strange place to
1505                         # make it absolutely certain that the link source
1506                         # has its own directory and isn't nested with some
1507                         # other custom mount (if so that mount's files would
1508                         # be linked, causing breakage.
1509                         cow_dir="/live/overlay/lib/live/mount/persistence/$(basename ${links_source})"
1510                         mkdir -p ${cow_dir}
1511                         chown_ref "${source}" "${cow_dir}"
1512                         chmod_ref "${source}" "${cow_dir}"
1513                         do_union ${links_source} ${cow_dir} ${source} ${rootfs_dest_backing}
1514                         link_files ${links_source} ${dest} "s|^${rootmnt}||"
1515                 elif [ -n "${opt_union}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1516                 then
1517                         do_union ${dest} ${source} ${rootfs_dest_backing}
1518                 elif [ -n "${opt_bind}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1519                 then
1520                         mount --bind "${source}" "${dest}"
1521                 elif [ -n "${opt_bind}" -o -n "${opt_union}" ] && [ -n "${PERSISTENCE_READONLY}" ]
1522                 then
1523                         # bind-mount and union mount are handled the same
1524                         # in read-only mode, but note that rootfs_dest_backing
1525                         # is non-empty (and necessary) only for unions
1526                         cow_dir="/live/overlay/${dest}"
1527                         if [ -e "${cow_dir}" ] && [ -z "${opt_link}" ]
1528                         then
1529                                 # If an earlier custom mount has files here
1530                                 # it will "block" the current mount's files
1531                                 # which is undesirable
1532                                 rm -rf "${cow_dir}"
1533                         fi
1534                         mkdir -p ${cow_dir}
1535                         chown_ref "${source}" "${cow_dir}"
1536                         chmod_ref "${source}" "${cow_dir}"
1537                         do_union ${dest} ${cow_dir} ${source} ${rootfs_dest_backing}
1538                 fi
1539
1540                 PERSISTENCE_IS_ON="1"
1541                 export PERSISTENCE_IS_ON
1542
1543                 if echo ${used_devices} | grep -qve "^\(.* \)\?${device}\( .*\)\?$"
1544                 then
1545                         used_devices="${used_devices} ${device}"
1546                 fi
1547         done < ${custom_mounts}
1548
1549         echo ${used_devices}
1550 }
1551
1552 is_mountpoint ()
1553 {
1554         directory="$1"
1555
1556         [ $(stat -fc%d:%D "${directory}") != $(stat -fc%d:%D "${directory}/..") ]
1557 }