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 $device
 688 # ends with a "/" this is a directory path.
 689 # If we're only probing $device (to check if it has custom persistence)
 690 # $probe should be set, which suppresses warnings upon failure. On
 691 # success, print the mount point for $device.
 692 mount_persistence_media ()
 693 {
 694         local device probe backing old_backing fstype mount_opts
 695         device=${1}
 696         probe=${2}
 697
 698         # get_custom_mounts() might call this with a directory path instead
 699         # of a block device path. This means we have found sub-directory path
 700         # underneath /lib/live/mounts/persistence, so we're done
 701         if [ -d "${device}" ]
 702         then
 703                 echo "${device}"
 704                 return 0
 705         fi
 706
 707         if [ ! -b "${device}" ]
 708         then
 709                 return 1
 710         fi
 711
 712         backing="/live/persistence/$(basename ${device})"
 713
 714         mkdir -p "${backing}"
 715         old_backing="$(where_is_mounted ${device})"
 716         if [ -z "${old_backing}" ]
 717         then
 718                 fstype="$(get_fstype ${device})"
 719                 mount_opts="rw,noatime"
 720                 if [ -n "${PERSISTENCE_READONLY}" ]
 721                 then
 722                         mount_opts="ro,noatime"
 723                 fi
 724                 if mount -t "${fstype}" -o "${mount_opts}" "${device}" "${backing}" >/dev/null
 725                 then
 726                         echo ${backing}
 727                         return 0
 728                 else
 729                         [ -z "${probe}" ] && log_warning_msg "Failed to mount persistence media ${device}"
 730                         rmdir "${backing}"
 731                         return 1
 732                 fi
 733         elif [ "${backing}" != "${old_backing}" ]
 734         then
 735                 if ! mount --move ${old_backing} ${backing} >/dev/null
 736                 then
 737                         [ -z "${probe}" ] && log_warning_msg "Failed to move persistence media ${device}"
 738                         rmdir "${backing}"
 739                         return 1
 740                 fi
 741                 mount_opts="rw,noatime"
 742                 if [ -n "${PERSISTENCE_READONLY}" ]
 743                 then
 744                         mount_opts="ro,noatime"
 745                 fi
 746                 if ! mount -o "remount,${mount_opts}" "${backing}" >/dev/null
 747                 then
 748                         log_warning_msg "Failed to remount persistence media ${device} writable"
 749                         # Don't unmount or rmdir the new mountpoint in this case
 750                 fi
 751                 echo ${backing}
 752                 return 0
 753         else
 754                 # This means that $device has already been mounted on
 755                 # the place expected by live-boot, so we're done.
 756                 echo ${backing}
 757                 return 0
 758         fi
 759 }
 760
 761 close_persistence_media ()
 762 {
 763         local device backing
 764         device=${1}
 765         backing="$(where_is_mounted ${device})"
 766
 767         if [ -d "${backing}" ]
 768         then
 769                 umount "${backing}" >/dev/null 2>&1
 770                 rmdir "${backing}" >/dev/null 2>&1
 771         fi
 772
 773         if is_active_luks_mapping ${device}
 774         then
 775                 /sbin/cryptsetup luksClose ${device}
 776         fi
 777 }
 778
 779 open_luks_device ()
 780 {
 781         dev="${1}"
 782         name="$(basename ${dev})"
 783         opts="--key-file=-"
 784         if [ -n "${PERSISTENCE_READONLY}" ]
 785         then
 786                 opts="${opts} --readonly"
 787         fi
 788
 789         if /sbin/cryptsetup status "${name}" >/dev/null 2>&1
 790         then
 791                 re="^[[:space:]]*device:[[:space:]]*\([^[:space:]]*\)$"
 792                 opened_dev=$(cryptsetup status ${name} 2>/dev/null | grep "${re}" | sed "s|${re}|\1|")
 793                 if [ "${opened_dev}" = "${dev}" ]
 794                 then
 795                         luks_device="/dev/mapper/${name}"
 796                         echo ${luks_device}
 797                         return 0
 798                 else
 799                         log_warning_msg "Cannot open luks device ${dev} since ${opened_dev} already is opened with its name"
 800                         return 1
 801                 fi
 802         fi
 803
 804         load_keymap
 805
 806         while true
 807         do
 808                 /lib/cryptsetup/askpass "Enter passphrase for ${dev}: " | \
 809                         /sbin/cryptsetup -T 1 luksOpen ${dev} ${name} ${opts}
 810
 811                 if [ 0 -eq ${?} ]
 812                 then
 813                         luks_device="/dev/mapper/${name}"
 814                         echo ${luks_device}
 815                         return 0
 816                 fi
 817
 818                 echo >&6
 819                 echo -n "There was an error decrypting ${dev} ... Retry? [Y/n] " >&6
 820                 read answer
 821
 822                 if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 823                 then
 824                         return 2
 825                 fi
 826         done
 827 }
 828
 829 get_gpt_name ()
 830 {
 831     local dev
 832     dev="${1}"
 833     /sbin/blkid -s PART_ENTRY_NAME -p -o value ${dev} 2>/dev/null
 834 }
 835
 836 is_gpt_device ()
 837 {
 838     local dev
 839     dev="${1}"
 840     [ "$(/sbin/blkid -s PART_ENTRY_SCHEME -p -o value ${dev} 2>/dev/null)" = "gpt" ]
 841 }
 842
 843 probe_for_gpt_name ()
 844 {
 845         local overlays dev gpt_dev gpt_name
 846         overlays="${1}"
 847         dev="${2}"
 848
 849         gpt_dev="${dev}"
 850         if is_active_luks_mapping ${dev}
 851         then
 852                 # if $dev is an opened luks device, we need to check
 853                 # GPT stuff on the backing device
 854                 gpt_dev=$(get_luks_backing_device "${dev}")
 855         fi
 856
 857         if ! is_gpt_device ${gpt_dev}
 858         then
 859                 return
 860         fi
 861
 862         gpt_name=$(get_gpt_name ${gpt_dev})
 863         for label in ${overlays}
 864         do
 865                 if [ "${gpt_name}" = "${label}" ]
 866                 then
 867                         echo "${label}=${dev}"
 868                 fi
 869         done
 870 }
 871
 872 probe_for_fs_label ()
 873 {
 874         local overlays dev
 875         overlays="${1}"
 876         dev="${2}"
 877
 878         for label in ${overlays}
 879         do
 880                 if [ "$(/sbin/blkid -s LABEL -o value $dev 2>/dev/null)" = "${label}" ]
 881                 then
 882                         echo "${label}=${dev}"
 883                 fi
 884         done
 885 }
 886
 887 probe_for_file_name ()
 888 {
 889         local overlays dev ret backing
 890         overlays="${1}"
 891         dev="${2}"
 892
 893         ret=""
 894         backing="$(mount_persistence_media ${dev} probe)"
 895         if [ -z "${backing}" ]
 896         then
 897             return
 898         fi
 899
 900         for label in ${overlays}
 901         do
 902                 path=${backing}/${PERSISTENCE_PATH}/${label}
 903                 if [ -f "${path}" ]
 904                 then
 905                         local loopdev
 906                         loopdev=$(setup_loop "${path}" "loop" "/sys/block/loop*")
 907                         ret="${ret} ${label}=${loopdev}"
 908                 fi
 909         done
 910
 911         if [ -n "${ret}" ]
 912         then
 913                 echo ${ret}
 914         else
 915                 # unmount and remove mountpoint
 916                 umount ${backing} > /dev/null 2>&1 || true
 917                 rmdir ${backing} > /dev/null 2>&1 || true
 918         fi
 919 }
 920
 921 probe_for_directory_name ()
 922 {
 923         local overlays dev ret backing
 924         overlays="${1}"
 925         dev="${2}"
 926
 927         ret=""
 928         backing="$(mount_persistence_media ${dev} probe)"
 929         if [ -z "${backing}" ]
 930         then
 931             return
 932         fi
 933
 934         for label in ${overlays}
 935         do
 936                 path=${backing}/${PERSISTENCE_PATH}/${label}
 937                 if [ -d "${path}" ]
 938                 then
 939                         # in this case the "device" ends with a "/"
 940                         ret="${ret} ${label}=${backing}/${PERSISTENCE_PATH}/${label%%/}/"
 941                 fi
 942         done
 943
 944         if [ -n "${ret}" ]
 945         then
 946                 echo ${ret}
 947         else
 948                 # unmount and remove mountpoint
 949                 umount ${backing} > /dev/null 2>&1 || true
 950                 rmdir ${backing} > /dev/null 2>&1 || true
 951         fi
 952 }
 953
 954 find_persistence_media ()
 955 {
 956         # Scans devices for overlays, and returns a whitespace
 957         # separated list of how to use them. Only overlays with a partition
 958         # label or file name in ${overlays} are returned.
 959         #
 960         # When scanning a LUKS device, the user will be asked to enter the
 961         # passphrase; on failure to enter it, or if no persistence partitions
 962         # or files were found, the LUKS device is closed.
 963         #
 964         # For all other cases (overlay partition and overlay file) the
 965         # return value is "${label}=${device}", where ${device} a device that
 966         # can mount the content. In the case of an overlay file, the device
 967         # containing the file will remain mounted as a side-effect.
 968         #
 969         # No devices in ${black_listed_devices} will be scanned, and if
 970         # ${white_list_devices} is non-empty, only devices in it will be
 971         # scanned.
 972
 973         local overlays white_listed_devices ret black_listed_devices
 974         overlays="${1}"
 975         white_listed_devices="${2}"
 976         ret=""
 977
 978         #
 979         # The devices that are hosting the actual live rootfs should not be
 980         # used for persistence storage since otherwise you might mount a
 981         # parent directory on top of a sub-directory of the same filesystem
 982         # in one union together.
 983         #
 984         black_listed_devices=""
 985         for d in /live/rootfs/* /live/findiso /live/fromiso
 986         do
 987                 black_listed_devices="${black_listed_devices} $(what_is_mounted_on d)"
 988         done
 989
 990         for dev in $(storage_devices "${black_listed_devices}" "${white_listed_devices}")
 991         do
 992                 local result luks_device
 993                 result=""
 994
 995                 luks_device=""
 996                 # Check if it's a luks device; we'll have to open the device
 997                 # in order to probe any filesystem it contains, like we do
 998                 # below. activate_custom_mounts() also depends on that any luks
 999                 # device already has been opened.
1000                 if is_in_comma_sep_list luks ${PERSISTENCE_ENCRYPTION} && is_luks_partition ${dev}
1001                 then
1002                         if luks_device=$(open_luks_device "${dev}")
1003                         then
1004                                 dev="${luks_device}"
1005                         else
1006                                 # skip $dev since we failed/chose not to open it
1007                                 continue
1008                         fi
1009                 elif ! is_in_comma_sep_list none ${PERSISTENCE_ENCRYPTION}
1010                 then
1011                         # skip $dev since we don't allow unencrypted storage
1012                         continue
1013                 fi
1014
1015                 # Probe for matching GPT partition names or filesystem labels
1016                 if is_in_comma_sep_list filesystem ${PERSISTENCE_STORAGE}
1017                 then
1018                         result=$(probe_for_gpt_name "${overlays}" ${dev})
1019                         if [ -n "${result}" ]
1020                         then
1021                                 ret="${ret} ${result}"
1022                                 continue
1023                         fi
1024
1025                         result=$(probe_for_fs_label "${overlays}" ${dev})
1026                         if [ -n "${result}" ]
1027                         then
1028                                 ret="${ret} ${result}"
1029                                 continue
1030                         fi
1031                 fi
1032
1033                 # Probe for files with matching name on mounted partition
1034                 if is_in_comma_sep_list file ${PERSISTENCE_STORAGE}
1035                 then
1036                         result=$(probe_for_file_name "${overlays}" ${dev})
1037                         if [ -n "${result}" ]
1038                         then
1039                                 local loopdevice
1040                                 loopdevice=${result##*=}
1041                                 if is_in_comma_sep_list luks ${PERSISTENCE_ENCRYPTION} && is_luks_partition ${loopdevice}
1042                                 then
1043                                         local luksfile
1044                                         luksfile=""
1045                                         if luksfile=$(open_luks_device "${loopdevice}")
1046                                         then
1047                                                 result=${result%%=*}
1048                                                 result="${result}=${luksfile}"
1049                                         else
1050                                                 losetup -d $loopdevice
1051                                                 result=""
1052                                         fi
1053                                 fi
1054                                 ret="${ret} ${result}"
1055                                 continue
1056                         fi
1057                 fi
1058
1059                 # Probe for directory with matching name on mounted partition
1060                 if is_in_comma_sep_list directory ${PERSISTENCE_STORAGE}
1061                 then
1062                         result=$(probe_for_directory_name "${overlays}" ${dev})
1063                         if [ -n "${result}" ]
1064                         then
1065                                 ret="${ret} ${result}"
1066                                 continue
1067                         fi
1068                 fi
1069
1070                 # Close luks device if it isn't used
1071                 if [ -z "${result}" ] && [ -n "${luks_device}" ] && is_active_luks_mapping "${luks_device}"
1072                 then
1073                         /sbin/cryptsetup luksClose "${luks_device}"
1074                 fi
1075         done
1076
1077         if [ -n "${ret}" ]
1078         then
1079                 echo ${ret}
1080         fi
1081 }
1082
1083 get_mac ()
1084 {
1085         mac=""
1086
1087         for adaptor in /sys/class/net/*
1088         do
1089                 status="$(cat ${adaptor}/iflink)"
1090
1091                 if [ "${status}" -eq 2 ]
1092                 then
1093                         mac="$(cat ${adaptor}/address)"
1094                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
1095                 fi
1096         done
1097
1098         echo ${mac}
1099 }
1100
1101 is_luks_partition ()
1102 {
1103         device="${1}"
1104         /sbin/cryptsetup isLuks "${device}" 1>/dev/null 2>&1
1105 }
1106
1107 is_active_luks_mapping ()
1108 {
1109         device="${1}"
1110         /sbin/cryptsetup status "${device}" 1>/dev/null 2>&1
1111 }
1112
1113 get_luks_backing_device ()
1114 {
1115         device=${1}
1116         cryptsetup status ${device} 2> /dev/null | \
1117                 awk '{if ($1 == "device:") print $2}'
1118 }
1119
1120 removable_dev ()
1121 {
1122         output_format="${1}"
1123         want_usb="${2}"
1124         ret=
1125
1126         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
1127         do
1128                 dev_ok=
1129                 if [ "$(cat ${sysblock}/removable)" = "1" ]
1130                 then
1131                         if [ -z "${want_usb}" ]
1132                         then
1133                                 dev_ok="true"
1134                         else
1135                                 if readlink ${sysblock} | grep -q usb
1136                                 then
1137                                         dev_ok="true"
1138                                 fi
1139                         fi
1140                 fi
1141
1142                 if [ "${dev_ok}" = "true" ]
1143                 then
1144                         case "${output_format}" in
1145                                 sys)
1146                                         ret="${ret} ${sysblock}"
1147                                         ;;
1148                                 *)
1149                                         devname=$(sys2dev "${sysblock}")
1150                                         ret="${ret} ${devname}"
1151                                         ;;
1152                         esac
1153                 fi
1154         done
1155
1156         echo "${ret}"
1157 }
1158
1159 removable_usb_dev ()
1160 {
1161         output_format="${1}"
1162
1163         removable_dev "${output_format}" "want_usb"
1164 }
1165
1166 non_removable_dev ()
1167 {
1168         output_format="${1}"
1169         ret=
1170
1171         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
1172         do
1173                 if [ "$(cat ${sysblock}/removable)" = "0" ]
1174                 then
1175                         case "${output_format}" in
1176                                 sys)
1177                                         ret="${ret} ${sysblock}"
1178                                         ;;
1179                                 *)
1180                                         devname=$(sys2dev "${sysblock}")
1181                                         ret="${ret} ${devname}"
1182                                         ;;
1183                         esac
1184                 fi
1185         done
1186
1187         echo "${ret}"
1188 }
1189
1190 link_files ()
1191 {
1192         # create source's directory structure in dest, and recursively
1193         # create symlinks in dest to to all files in source. if mask
1194         # is non-empty, remove mask from all source paths when
1195         # creating links (will be necessary if we change root, which
1196         # live-boot normally does (into $rootmnt)).
1197         local src_dir dest_dir src_transform
1198
1199         # remove multiple /:s and ensure ending on /
1200         src_dir="$(trim_path ${1})/"
1201         dest_dir="$(trim_path ${2})/"
1202         src_transform="${3}"
1203
1204         # This check can only trigger on the inital, non-recursive call since
1205         # we create the destination before recursive calls
1206         if [ ! -d "${dest_dir}" ]
1207         then
1208                 log_warning_msg "Must link_files into a directory"
1209                 return
1210         fi
1211
1212         find "${src_dir}" -mindepth 1 -maxdepth 1 | \
1213         while read src
1214         do
1215                 local dest final_src
1216                 dest="${dest_dir}$(basename "${src}")"
1217                 if [ -d "${src}" ]
1218                 then
1219                         if [ -z "$(ls -A "${src}")" ]
1220                         then
1221                                 continue
1222                         fi
1223                         if [ ! -d "${dest}" ]
1224                         then
1225                                 mkdir -p "${dest}"
1226                                 chown_ref "${src}" "${dest}"
1227                                 chmod_ref "${src}" "${dest}"
1228                         fi
1229                         link_files "${src}" "${dest}" "${src_transform}"
1230                 else
1231                         final_src=${src}
1232                         if [ -n "${src_transform}" ]
1233                         then
1234                                 final_src="$(echo ${final_src} | sed "${src_transform}")"
1235                         fi
1236                         rm -rf "${dest}" 2> /dev/null
1237                         ln -s "${final_src}" "${dest}"
1238                         chown_ref "${src}" "${dest}"
1239                 fi
1240         done
1241 }
1242
1243 do_union ()
1244 {
1245         local unionmountpoint unionrw unionro
1246         unionmountpoint="${1}"  # directory where the union is mounted
1247         shift
1248         unionrw="${1}"          # branch where the union changes are stored
1249         shift
1250         unionro="${*}"          # space separated list of read-only branches (optional)
1251
1252         case "${UNIONTYPE}" in
1253                 aufs)
1254                         rw_opt="rw"
1255                         ro_opt="rr+wh"
1256                         noxino_opt="noxino"
1257                         ;;
1258
1259                 unionfs-fuse)
1260                         rw_opt="RW"
1261                         ro_opt="RO"
1262                         ;;
1263
1264                 *)
1265                         rw_opt="rw"
1266                         ro_opt="ro"
1267                         ;;
1268         esac
1269
1270         case "${UNIONTYPE}" in
1271                 unionfs-fuse)
1272                         unionmountopts="-o cow -o noinitgroups -o default_permissions -o allow_other -o use_ino -o suid"
1273                         unionmountopts="${unionmountopts} ${unionrw}=${rw_opt}"
1274                         if [ -n "${unionro}" ]
1275                         then
1276                                 for rofs in ${unionro}
1277                                 do
1278                                         unionmountopts="${unionmountopts}:${rofs}=${ro_opt}"
1279                                 done
1280                         fi
1281                         ( sysctl -w fs.file-max=391524 ; ulimit -HSn 16384
1282                         unionfs-fuse ${unionmountopts} "${unionmountpoint}" ) && \
1283                         ( mkdir -p /run/sendsigs.omit.d
1284                         pidof unionfs-fuse >> /run/sendsigs.omit.d/unionfs-fuse || true )
1285                         ;;
1286
1287                 overlayfs)
1288                         # XXX: can multiple unionro be used? (overlayfs only handles two dirs, but perhaps they can be chained?)
1289                         # XXX: and can unionro be optional? i.e. can overlayfs skip lowerdir?
1290                         if echo ${unionro} | grep -q " "
1291                         then
1292                                 panic "Multiple lower filesystems are currently not supported with overlayfs (unionro = ${unionro})."
1293                         elif [ -z "${unionro}"  ]
1294                         then
1295                                 panic "Overlayfs needs at least one lower filesystem (read-only branch)."
1296                         fi
1297                         unionmountopts="-o noatime,lowerdir=${unionro},upperdir=${unionrw}"
1298                         mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
1299                         ;;
1300
1301                 *)
1302                         unionmountopts="-o noatime,${noxino_opt},dirs=${unionrw}=${rw_opt}"
1303                         if [ -n "${unionro}" ]
1304                         then
1305                                 for rofs in ${unionro}
1306                                 do
1307                                         unionmountopts="${unionmountopts}:${rofs}=${ro_opt}"
1308                                 done
1309                         fi
1310                         mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
1311                         ;;
1312         esac
1313 }
1314
1315 get_custom_mounts ()
1316 {
1317         # Side-effect: leaves $devices with persistence.conf mounted in /live/persistence
1318         # Side-effect: prints info to file $custom_mounts
1319
1320         local custom_mounts devices bindings links
1321         custom_mounts=${1}
1322         shift
1323         devices=${@}
1324
1325         bindings="/tmp/bindings.list"
1326         links="/tmp/links.list"
1327         rm -rf ${bindings} ${links} 2> /dev/null
1328
1329         for device in ${devices}
1330         do
1331                 local device_name backing include_list
1332                 device_name="$(basename ${device})"
1333                 backing=$(mount_persistence_media ${device})
1334                 if [ -z "${backing}" ]
1335                 then
1336                         continue
1337                 fi
1338
1339                 if [ -r "${backing}/${persistence_list}" ]
1340                 then
1341                         include_list="${backing}/${persistence_list}"
1342                 else
1343                         continue
1344                 fi
1345
1346                 if [ -n "${LIVE_BOOT_DEBUG}" ] && [ -e "${include_list}" ]
1347                 then
1348                         cp ${include_list} /live/persistence/${persistence_list}.${device_name}
1349                 fi
1350
1351                 while read dir options # < ${include_list}
1352                 do
1353                         if echo ${dir} | grep -qe "^[[:space:]]*\(#.*\)\?$"
1354                         then
1355                                 # skipping empty or commented lines
1356                                 continue
1357                         fi
1358
1359                         if trim_path ${dir} | grep -q -e "^[^/]" -e "^/lib" -e "^/lib/live\(/.*\)\?$" -e "^/\(.*/\)\?\.\.\?\(/.*\)\?$"
1360                         then
1361                                 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."
1362                                 continue
1363                         fi
1364
1365                         local opt_source opt_link source full_source full_dest
1366                         opt_source=""
1367                         opt_link=""
1368                         for opt in $(echo ${options} | tr ',' ' ');
1369                         do
1370                                 case "${opt}" in
1371                                         source=*)
1372                                                 opt_source=${opt#source=}
1373                                                 ;;
1374                                         link)
1375                                                 opt_link="true"
1376                                                 ;;
1377                                         union|bind)
1378                                                 ;;
1379                                         *)
1380                                                 log_warning_msg "Skipping custom mount with unkown option: ${opt}"
1381                                                 continue 2
1382                                                 ;;
1383                                 esac
1384                         done
1385
1386                         source="${dir}"
1387                         if [ -n "${opt_source}" ]
1388                         then
1389                                 if echo ${opt_source} | grep -q -e "^/" -e "^\(.*/\)\?\.\.\?\(/.*\)\?$" && [ "${opt_source}" != "." ]
1390                                 then
1391                                         log_warning_msg "Skipping unsafe custom mount with option source=${opt_source}: must be either \".\" (the media root) or a relative path w.r.t. the media root that contains neither comas, nor the special \".\" and \"..\" path components"
1392                                         continue
1393                                 else
1394                                         source="${opt_source}"
1395                                 fi
1396                         fi
1397
1398                         full_source="$(trim_path ${backing}/${source})"
1399                         full_dest="$(trim_path ${rootmnt}/${dir})"
1400                         if [ -n "${opt_link}" ]
1401                         then
1402                                 echo "${device} ${full_source} ${full_dest} ${options}" >> ${links}
1403                         else
1404                                 echo "${device} ${full_source} ${full_dest} ${options}" >> ${bindings}
1405                         fi
1406                 done < ${include_list}
1407         done
1408
1409         # We sort the list according to destination so we're sure that
1410         # we won't hide a previous mount. We also ignore duplicate
1411         # destinations in a more or less arbitrary way.
1412         [ -e "${bindings}" ] && sort -k3 -sbu ${bindings} >> ${custom_mounts} && rm ${bindings}
1413
1414         # After all mounts are considered we add symlinks so they
1415         # won't be hidden by some mount.
1416         [ -e "${links}" ] && cat ${links} >> ${custom_mounts} && rm ${links}
1417
1418         # We need to make sure that no two custom mounts have the same sources
1419         # or are nested; if that is the case, too much weird stuff can happen.
1420         local prev_source prev_dest
1421         prev_source="impossible source" # first iteration must not match
1422         prev_dest=""
1423         # This sort will ensure that a source /a comes right before a source
1424         # /a/b so we only need to look at the previous source
1425         sort -k2 -b ${custom_mounts} |
1426         while read device source dest options
1427         do
1428                 if echo ${source} | grep -qe "^${prev_source}\(/.*\)\?$"
1429                 then
1430                         panic "Two persistence mounts have the same or nested sources: ${source} on ${dest}, and ${prev_source} on ${prev_dest}"
1431                 fi
1432                 prev_source=${source}
1433                 prev_dest=${dest}
1434         done
1435 }
1436
1437 activate_custom_mounts ()
1438 {
1439         local custom_mounts used_devices
1440         custom_mounts="${1}" # the ouput from get_custom_mounts()
1441         used_devices=""
1442
1443         while read device source dest options # < ${custom_mounts}
1444         do
1445                 local opt_bind opt_link opt_union
1446                 opt_bind="true"
1447                 opt_link=""
1448                 opt_union=""
1449                 for opt in $(echo ${options} | tr ',' ' ');
1450                 do
1451                         case "${opt}" in
1452                                 bind)
1453                                         opt_bind="true"
1454                                         unset opt_link opt_union
1455                                         ;;
1456                                 link)
1457                                         opt_link="true"
1458                                         unset opt_bind opt_union
1459                                         ;;
1460                                 union)
1461                                         opt_union="true"
1462                                         unset opt_bind opt_link
1463                                         ;;
1464                         esac
1465                 done
1466
1467                 if [ -n "$(what_is_mounted_on "${dest}")" ]
1468                 then
1469                         if [ "${dest}" = "${rootmnt}" ]
1470                         then
1471                                 umount "${dest}"
1472                         else
1473                                 log_warning_msg "Skipping custom mount ${dest}: $(what_is_mounted_on "${dest}") is already mounted there"
1474                                 continue
1475                         fi
1476                 fi
1477
1478                 if [ ! -d "${dest}" ]
1479                 then
1480                         # create the destination and delete existing files in
1481                         # its path that are in the way
1482                         path="/"
1483                         for dir in $(echo ${dest} | sed -e 's|/\+| |g')
1484                         do
1485                                 path=$(trim_path ${path}/${dir})
1486                                 if [ -f ${path} ]
1487                                 then
1488                                         rm -f ${path}
1489                                 fi
1490                                 if [ ! -e ${path} ]
1491                                 then
1492                                         mkdir -p ${path}
1493                                         if echo ${path} | grep -qe "^${rootmnt}/*home/[^/]\+"
1494                                         then
1495                                                 # if ${dest} is in /home try fixing proper ownership by assuming that the intended user is the first, which is usually the case
1496                                                 # FIXME: this should really be handled by live-config since we don't know for sure which uid a certain user has until then
1497                                                 chown 1000:1000 ${path}
1498                                         fi
1499                                 fi
1500                         done
1501                 fi
1502
1503                 # if ${source} doesn't exist on our persistence media
1504                 # we bootstrap it with $dest from the live filesystem.
1505                 # this both makes sense and is critical if we're
1506                 # dealing with /etc or other system dir.
1507                 if [ ! -d "${source}" ]
1508                 then
1509                         if [ -n "${PERSISTENCE_READONLY}" ]
1510                         then
1511                                 continue
1512                         elif [ -n "${opt_union}" ] || [ -n "${opt_link}" ]
1513                         then
1514                                 # unions and don't need to be bootstrapped
1515                                 # link dirs can't be bootstrapped in a sensible way
1516                                 mkdir -p "${source}"
1517                                 chown_ref "${dest}" "${source}"
1518                                 chmod_ref "${dest}" "${source}"
1519                         elif [ -n "${opt_bind}" ]
1520                         then
1521                                 # ensure that $dest is not copied *into* $source
1522                                 mkdir -p "$(dirname ${source})"
1523                                 cp -a "${dest}" "${source}"
1524                         fi
1525                 fi
1526
1527                 # XXX: If CONFIG_AUFS_ROBR is added to the Debian kernel we can
1528                 # ignore the loop below and set rootfs_dest_backing=$dest
1529                 local rootfs_dest_backing
1530                 rootfs_dest_backing=""
1531                 if [ -n "${opt_link}" ] || [ -n "${opt_union}" ]
1532                 then
1533                         for d in /live/rootfs/*
1534                         do
1535                                 if [ -n "${rootmnt}" ]
1536                                 then
1537                                         fs="${d}/$(echo ${dest} | sed -e "s|${rootmnt}||")"
1538                                 else
1539                                         fs="${d}/${dest}"
1540                                 fi
1541                                 if [ -d "${fs}" ]
1542                                 then
1543                                         rootfs_dest_backing="${rootfs_dest_backing} ${fs}"
1544                                 fi
1545                         done
1546                 fi
1547
1548                 local cow_dir links_source
1549                 if [ -n "${opt_link}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1550                 then
1551                         link_files ${source} ${dest} "s|^/live/|/lib/live/mount/|"
1552                 elif [ -n "${opt_link}" ] && [ -n "${PERSISTENCE_READONLY}" ]
1553                 then
1554                         mkdir -p ${rootmnt}/lib/live/mount/persistence
1555                         links_source=$(mktemp -d ${rootmnt}/lib/live/mount/persistence/links-source-XXXXXX)
1556                         chown_ref ${source} ${links_source}
1557                         chmod_ref ${source} ${links_source}
1558                         # We put the cow dir in the below strange place to
1559                         # make it absolutely certain that the link source
1560                         # has its own directory and isn't nested with some
1561                         # other custom mount (if so that mount's files would
1562                         # be linked, causing breakage.
1563                         cow_dir="/live/overlay/lib/live/mount/persistence/$(basename ${links_source})"
1564                         mkdir -p ${cow_dir}
1565                         chown_ref "${source}" "${cow_dir}"
1566                         chmod_ref "${source}" "${cow_dir}"
1567                         do_union ${links_source} ${cow_dir} ${source} ${rootfs_dest_backing}
1568                         link_files ${links_source} ${dest} "s|^${rootmnt}||"
1569                 elif [ -n "${opt_union}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1570                 then
1571                         do_union ${dest} ${source} ${rootfs_dest_backing}
1572                 elif [ -n "${opt_bind}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1573                 then
1574                         mount --bind "${source}" "${dest}"
1575                 elif [ -n "${opt_bind}" -o -n "${opt_union}" ] && [ -n "${PERSISTENCE_READONLY}" ]
1576                 then
1577                         # bind-mount and union mount are handled the same
1578                         # in read-only mode, but note that rootfs_dest_backing
1579                         # is non-empty (and necessary) only for unions
1580                         cow_dir="/live/overlay/${dest}"
1581                         if [ -e "${cow_dir}" ] && [ -z "${opt_link}" ]
1582                         then
1583                                 # If an earlier custom mount has files here
1584                                 # it will "block" the current mount's files
1585                                 # which is undesirable
1586                                 rm -rf "${cow_dir}"
1587                         fi
1588                         mkdir -p ${cow_dir}
1589                         chown_ref "${source}" "${cow_dir}"
1590                         chmod_ref "${source}" "${cow_dir}"
1591                         do_union ${dest} ${cow_dir} ${source} ${rootfs_dest_backing}
1592                 fi
1593
1594                 PERSISTENCE_IS_ON="1"
1595                 export PERSISTENCE_IS_ON
1596
1597                 if echo ${used_devices} | grep -qve "^\(.* \)\?${device}\( .*\)\?$"
1598                 then
1599                         used_devices="${used_devices} ${device}"
1600                 fi
1601         done < ${custom_mounts}
1602
1603         echo ${used_devices}
1604 }
1605
1606 is_mountpoint ()
1607 {
1608         directory="$1"
1609
1610         [ $(stat -fc%d:%D "${directory}") != $(stat -fc%d:%D "${directory}/..") ]
1611 }