scripts/boot/9990-misc-helpers.sh

   1 #!/bin/sh
   2
   3 #set -e
   4
   5 is_live_path ()
   6 {
   7         DIRECTORY="${1}"
   8
   9         if [ -d "${DIRECTORY}"/"${LIVE_MEDIA_PATH}" ]
  10         then
  11                 for FILESYSTEM in squashfs ext2 ext3 ext4 xfs dir jffs2
  12                 do
  13                         if [ "$(echo ${DIRECTORY}/${LIVE_MEDIA_PATH}/*.${FILESYSTEM})" != "${DIRECTORY}/${LIVE_MEDIA_PATH}/*.${FILESYSTEM}" ]
  14                         then
  15                                 return 0
  16                         fi
  17                 done
  18         fi
  19
  20         return 1
  21 }
  22
  23 matches_uuid ()
  24 {
  25         if [ "${IGNORE_UUID}" ] || [ ! -e /conf/uuid.conf ]
  26         then
  27                 return 0
  28         fi
  29
  30         path="${1}"
  31         uuid="$(cat /conf/uuid.conf)"
  32
  33         for try_uuid_file in "${path}/.disk/live-uuid"*
  34         do
  35                 [ -e "${try_uuid_file}" ] || continue
  36
  37                 try_uuid="$(cat "${try_uuid_file}")"
  38
  39                 if [ "${uuid}" = "${try_uuid}" ]
  40                 then
  41                         return 0
  42                 fi
  43         done
  44
  45         return 1
  46 }
  47
  48 get_backing_device ()
  49 {
  50         case "${1}" in
  51                 *.squashfs|*.ext2|*.ext3|*.ext4|*.jffs2)
  52                         echo $(setup_loop "${1}" "loop" "/sys/block/loop*" '0' "${LIVE_MEDIA_ENCRYPTION}" "${2}")
  53                         ;;
  54
  55                 *.dir)
  56                         echo "directory"
  57                         ;;
  58
  59                 *)
  60                         panic "Unrecognized live filesystem: ${1}"
  61                         ;;
  62         esac
  63 }
  64
  65 match_files_in_dir ()
  66 {
  67         # Does any files match pattern ${1} ?
  68         local pattern
  69         pattern="${1}"
  70
  71         if [ "$(echo ${pattern})" != "${pattern}" ]
  72         then
  73                 return 0
  74         fi
  75
  76         return 1
  77 }
  78
  79 mount_images_in_directory ()
  80 {
  81         directory="${1}"
  82         rootmnt="${2}"
  83         mac="${3}"
  84
  85         if match_files_in_dir "${directory}/${LIVE_MEDIA_PATH}/*.squashfs" ||
  86                 match_files_in_dir "${directory}/${LIVE_MEDIA_PATH}/*.ext2" ||
  87                 match_files_in_dir "${directory}/${LIVE_MEDIA_PATH}/*.ext3" ||
  88                 match_files_in_dir "${directory}/${LIVE_MEDIA_PATH}/*.ext4" ||
  89                 match_files_in_dir "${directory}/${LIVE_MEDIA_PATH}/*.jffs2" ||
  90                 match_files_in_dir "${directory}/${LIVE_MEDIA_PATH}/*.dir"
  91         then
  92                 [ -n "${mac}" ] && adddirectory="${directory}/${LIVE_MEDIA_PATH}/${mac}"
  93                 setup_unionfs "${directory}/${LIVE_MEDIA_PATH}" "${rootmnt}" "${adddirectory}"
  94         else
  95                 panic "No supported filesystem images found at /${LIVE_MEDIA_PATH}."
  96         fi
  97 }
  98
  99 is_nice_device ()
 100 {
 101         sysfs_path="${1#/sys}"
 102
 103         if /sbin/udevadm test-builtin path_id "${sysfs_path}" | egrep -q "ID_PATH=(usb|pci-[^-]*-(ide|sas|scsi|usb|virtio)|platform-sata_mv|platform-orion-ehci|platform-mmc|platform-mxsdhci)"
 104         then
 105                 return 0
 106         elif echo "${sysfs_path}" | grep -q '^/block/vd[a-z]$'
 107         then
 108                 return 0
 109         elif echo ${sysfs_path} | grep -q "^/block/dm-"
 110         then
 111                 return 0
 112         elif echo ${sysfs_path} | grep -q "^/block/mtdblock"
 113         then
 114                 return 0
 115         fi
 116
 117         return 1
 118 }
 119
 120 check_dev ()
 121 {
 122         sysdev="${1}"
 123         devname="${2}"
 124         skip_uuid_check="${3}"
 125
 126         # support for fromiso=.../isofrom=....
 127         if [ -n "$FROMISO" ]
 128         then
 129                 ISO_DEVICE=$(dirname $FROMISO)
 130                 if ! [ -b $ISO_DEVICE ]
 131                 then
 132                         # to support unusual device names like /dev/cciss/c0d0p1
 133                         # as well we have to identify the block device name, let's
 134                         # do that for up to 15 levels
 135                         i=15
 136                         while [ -n "$ISO_DEVICE" ] && [ "$i" -gt 0 ]
 137                         do
 138                                 ISO_DEVICE=$(dirname ${ISO_DEVICE})
 139                                 [ -b "$ISO_DEVICE" ] && break
 140                                 i=$(($i -1))
 141                         done
 142                 fi
 143
 144                 if [ "$ISO_DEVICE" = "/" ]
 145                 then
 146                         echo "Warning: device for bootoption fromiso= ($FROMISO) not found.">>/boot.log
 147                 else
 148                         fs_type=$(get_fstype "${ISO_DEVICE}")
 149                         if is_supported_fs ${fs_type}
 150                         then
 151                                 mkdir /live/fromiso
 152                                 mount -t $fs_type "$ISO_DEVICE" /live/fromiso
 153                                 ISO_NAME="$(echo $FROMISO | sed "s|$ISO_DEVICE||")"
 154                                 loopdevname=$(setup_loop "/live/fromiso/${ISO_NAME}" "loop" "/sys/block/loop*" "" '')
 155                                 devname="${loopdevname}"
 156                         else
 157                                 echo "Warning: unable to mount $ISO_DEVICE." >>/boot.log
 158                         fi
 159                 fi
 160         fi
 161
 162         if [ -z "${devname}" ]
 163         then
 164                 devname=$(sys2dev "${sysdev}")
 165         fi
 166
 167         if [ -d "${devname}" ]
 168         then
 169                 mount -o bind "${devname}" $mountpoint || continue
 170
 171                 if is_live_path $mountpoint
 172                 then
 173                         echo $mountpoint
 174                         return 0
 175                 else
 176                         umount $mountpoint
 177                 fi
 178         fi
 179
 180         IFS=","
 181         for device in ${devname}
 182         do
 183                 case "$device" in
 184                         *mapper*)
 185                                 # Adding lvm support
 186                                 if [ -x /scripts/local-top/lvm2 ]
 187                                 then
 188                                         ROOT="$device" resume="" /scripts/local-top/lvm2
 189                                 fi
 190                                 ;;
 191
 192                         /dev/md*)
 193                                 # Adding raid support
 194                                 if [ -x /scripts/local-top/mdadm ]
 195                                 then
 196                                         cp /conf/conf.d/md /conf/conf.d/md.orig
 197                                         echo "MD_DEVS=$device " >> /conf/conf.d/md
 198                                         /scripts/local-top/mdadm
 199                                         mv /conf/conf.d/md.orig /conf/conf.d/md
 200                                 fi
 201                                 ;;
 202                 esac
 203         done
 204         unset IFS
 205
 206         [ -n "$device" ] && devname="$device"
 207
 208         [ -e "$devname" ] || continue
 209
 210         if [ -n "${LIVE_MEDIA_OFFSET}" ]
 211         then
 212                 loopdevname=$(setup_loop "${devname}" "loop" "/sys/block/loop*" "${LIVE_MEDIA_OFFSET}" '')
 213                 devname="${loopdevname}"
 214         fi
 215
 216         fstype=$(get_fstype "${devname}")
 217
 218         if is_supported_fs ${fstype}
 219         then
 220                 devuid=$(blkid -o value -s UUID "$devname")
 221                 [ -n "$devuid" ] && grep -qs "\<$devuid\>" $tried && continue
 222                 mount -t ${fstype} -o ro,noatime "${devname}" ${mountpoint} || continue
 223                 [ -n "$devuid" ] && echo "$devuid" >> $tried
 224
 225                 if [ -n "${FINDISO}" ]
 226                 then
 227                         if [ -f ${mountpoint}/${FINDISO} ]
 228                         then
 229                                 umount ${mountpoint}
 230                                 mkdir -p /live/findiso
 231                                 mount -t ${fstype} -o ro,noatime "${devname}" /live/findiso
 232                                 loopdevname=$(setup_loop "/live/findiso/${FINDISO}" "loop" "/sys/block/loop*" 0 "")
 233                                 devname="${loopdevname}"
 234                                 mount -t iso9660 -o ro,noatime "${devname}" ${mountpoint}
 235                         else
 236                                 umount ${mountpoint}
 237                         fi
 238                 fi
 239
 240                 if is_live_path ${mountpoint} && \
 241                         ([ "${skip_uuid_check}" ] || matches_uuid ${mountpoint})
 242                 then
 243                         echo ${mountpoint}
 244                         return 0
 245                 else
 246                         umount ${mountpoint} 2>/dev/null
 247                 fi
 248         fi
 249
 250         if [ -n "${LIVE_MEDIA_OFFSET}" ]
 251         then
 252                 losetup -d "${loopdevname}"
 253         fi
 254
 255         return 1
 256 }
 257
 258 find_livefs ()
 259 {
 260         timeout="${1}"
 261
 262         # don't start autodetection before timeout has expired
 263         if [ -n "${LIVE_MEDIA_TIMEOUT}" ]
 264         then
 265                 if [ "${timeout}" -lt "${LIVE_MEDIA_TIMEOUT}" ]
 266                 then
 267                         return 1
 268                 fi
 269         fi
 270
 271         # first look at the one specified in the command line
 272         case "${LIVE_MEDIA}" in
 273                 removable-usb)
 274                         for sysblock in $(removable_usb_dev "sys")
 275                         do
 276                                 for dev in $(subdevices "${sysblock}")
 277                                 do
 278                                         if check_dev "${dev}"
 279                                         then
 280                                                 return 0
 281                                         fi
 282                                 done
 283                         done
 284                         return 1
 285                         ;;
 286
 287                 removable)
 288                         for sysblock in $(removable_dev "sys")
 289                         do
 290                                 for dev in $(subdevices "${sysblock}")
 291                                 do
 292                                         if check_dev "${dev}"
 293                                         then
 294                                                 return 0
 295                                         fi
 296                                 done
 297                         done
 298                         return 1
 299                         ;;
 300
 301                 *)
 302                         if [ ! -z "${LIVE_MEDIA}" ]
 303                         then
 304                                 if check_dev "null" "${LIVE_MEDIA}" "skip_uuid_check"
 305                                 then
 306                                         return 0
 307                                 fi
 308                         fi
 309                         ;;
 310         esac
 311
 312         # or do the scan of block devices
 313         # prefer removable devices over non-removable devices, so scan them first
 314         devices_to_scan="$(removable_dev 'sys') $(non_removable_dev 'sys')"
 315
 316         for sysblock in $devices_to_scan
 317         do
 318                 devname=$(sys2dev "${sysblock}")
 319                 [ -e "$devname" ] || continue
 320                 fstype=$(get_fstype "${devname}")
 321
 322                 if /lib/udev/cdrom_id ${devname} > /dev/null
 323                 then
 324                         if check_dev "null" "${devname}"
 325                         then
 326                                 return 0
 327                         fi
 328                 elif is_nice_device "${sysblock}"
 329                 then
 330                         for dev in $(subdevices "${sysblock}")
 331                         do
 332                                 if check_dev "${dev}"
 333                                 then
 334                                         return 0
 335                                 fi
 336                         done
 337                 elif [ "${fstype}" = "squashfs" -o \
 338                         "${fstype}" = "btrfs" -o \
 339                         "${fstype}" = "ext2" -o \
 340                         "${fstype}" = "ext3" -o \
 341                         "${fstype}" = "ext4" -o \
 342                         "${fstype}" = "jffs2" ]
 343                 then
 344                         # This is an ugly hack situation, the block device has
 345                         # an image directly on it.  It's hopefully
 346                         # live-boot, so take it and run with it.
 347                         ln -s "${devname}" "${devname}.${fstype}"
 348                         echo "${devname}.${fstype}"
 349                         return 0
 350                 fi
 351         done
 352
 353         return 1
 354 }
 355
 356 really_export ()
 357 {
 358         STRING="${1}"
 359         VALUE="$(eval echo -n \${$STRING})"
 360
 361         if [ -f /live.vars ] && grep -sq "export ${STRING}" /live.vars
 362         then
 363                 sed -i -e 's/\('${STRING}'=\).*$/\1'${VALUE}'/' /live.vars
 364         else
 365                 echo "export ${STRING}=\"${VALUE}\"" >> /live.vars
 366         fi
 367
 368         eval export "${STRING}"="${VALUE}"
 369 }
 370
 371 is_in_list_separator_helper ()
 372 {
 373         local sep element list
 374         sep=${1}
 375         shift
 376         element=${1}
 377         shift
 378         list=${*}
 379         echo ${list} | grep -qe "^\(.*${sep}\)\?${element}\(${sep}.*\)\?$"
 380 }
 381
 382 is_in_space_sep_list ()
 383 {
 384         local element
 385         element=${1}
 386         shift
 387         is_in_list_separator_helper "[[:space:]]" "${element}" "${*}"
 388 }
 389
 390 is_in_comma_sep_list ()
 391 {
 392         local element
 393         element=${1}
 394         shift
 395         is_in_list_separator_helper "," "${element}" "${*}"
 396 }
 397
 398 sys2dev ()
 399 {
 400         sysdev=${1#/sys}
 401         echo "/dev/$($udevinfo -q name -p ${sysdev} 2>/dev/null|| echo ${sysdev##*/})"
 402 }
 403
 404 subdevices ()
 405 {
 406         sysblock=${1}
 407         r=""
 408
 409         for dev in "${sysblock}"/* "${sysblock}"
 410         do
 411                 if [ -e "${dev}/dev" ]
 412                 then
 413                         r="${r} ${dev}"
 414                 fi
 415         done
 416
 417         echo ${r}
 418 }
 419
 420 storage_devices()
 421 {
 422         black_listed_devices="${1}"
 423         white_listed_devices="${2}"
 424
 425         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "loop|ram|fd")
 426         do
 427                 fulldevname=$(sys2dev "${sysblock}")
 428
 429                 if is_in_space_sep_list ${fulldevname} ${black_listed_devices} || \
 430                         [ -n "${white_listed_devices}" ] && \
 431                         ! is_in_space_sep_list ${fulldevname} ${white_listed_devices}
 432                 then
 433                         # skip this device entirely
 434                         continue
 435                 fi
 436
 437                 for dev in $(subdevices "${sysblock}")
 438                 do
 439                         devname=$(sys2dev "${dev}")
 440
 441                         if is_in_space_sep_list ${devname} ${black_listed_devices}
 442                         then
 443                                 # skip this subdevice
 444                                 continue
 445                         else
 446                                 echo "${devname}"
 447                         fi
 448                 done
 449         done
 450 }
 451
 452 is_supported_fs ()
 453 {
 454         fstype="${1}"
 455
 456         # Validate input first
 457         if [ -z "${fstype}" ]
 458         then
 459                 return 1
 460         fi
 461
 462         # Try to look if it is already supported by the kernel
 463         if grep -q ${fstype} /proc/filesystems
 464         then
 465                 return 0
 466         else
 467                 # Then try to add support for it the gentle way using the initramfs capabilities
 468                 modprobe ${fstype}
 469                 if grep -q ${fstype} /proc/filesystems
 470                 then
 471                         return 0
 472                 # Then try the hard way if /root is already reachable
 473                 else
 474                         kmodule="/root/lib/modules/`uname -r`/${fstype}/${fstype}.ko"
 475                         if [ -e "${kmodule}" ]
 476                         then
 477                                 insmod "${kmodule}"
 478                                 if grep -q ${fstype} /proc/filesystems
 479                                 then
 480                                         return 0
 481                                 fi
 482                         fi
 483                 fi
 484         fi
 485
 486         return 1
 487 }
 488
 489 get_fstype ()
 490 {
 491         /sbin/blkid -s TYPE -o value $1 2>/dev/null
 492 }
 493
 494 where_is_mounted ()
 495 {
 496         device=${1}
 497         # return first found
 498         grep -m1 "^${device} " /proc/mounts | cut -f2 -d ' '
 499 }
 500
 501 trim_path ()
 502 {
 503         # remove all unnecessary /:s in the path, including last one (except
 504         # if path is just "/")
 505         echo ${1} | sed 's|//\+|/|g' | sed 's|^\(.*[^/]\)/$|\1|'
 506 }
 507
 508 what_is_mounted_on ()
 509 {
 510         local dir
 511         dir="$(trim_path ${1})"
 512         grep -m1 "^[^ ]\+ ${dir} " /proc/mounts | cut -d' ' -f1
 513 }
 514
 515 chown_ref ()
 516 {
 517         local reference targets owner
 518         reference="${1}"
 519         shift
 520         targets=${@}
 521         owner=$(stat -c %u:%g "${reference}")
 522         chown -h ${owner} ${targets}
 523 }
 524
 525 chmod_ref ()
 526 {
 527         local reference targets rights
 528         reference="${1}"
 529         shift
 530         targets=${@}
 531         rights=$(stat -c %a "${reference}")
 532         chmod ${rights} ${targets}
 533 }
 534
 535 lastline ()
 536 {
 537         while read lines
 538         do
 539                 line=${lines}
 540         done
 541
 542         echo "${line}"
 543 }
 544
 545 base_path ()
 546 {
 547         testpath="${1}"
 548         mounts="$(awk '{print $2}' /proc/mounts)"
 549         testpath="$(busybox realpath ${testpath})"
 550
 551         while true
 552         do
 553                 if echo "${mounts}" | grep -qs "^${testpath}"
 554                 then
 555                         set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
 556                         echo ${1}
 557                         break
 558                 else
 559                         testpath=$(dirname $testpath)
 560                 fi
 561         done
 562 }
 563
 564 fs_size ()
 565 {
 566         # Returns used/free fs kbytes + 5% more
 567         # You could pass a block device as ${1} or the mount point as ${2}
 568
 569         dev="${1}"
 570         mountp="${2}"
 571         used="${3}"
 572
 573         if [ -z "${mountp}" ]
 574         then
 575                 mountp="$(where_is_mounted ${dev})"
 576
 577                 if [ -z "${mountp}" ]
 578                 then
 579                         mountp="/mnt/tmp_fs_size"
 580
 581                         mkdir -p "${mountp}"
 582                         mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}" || log_warning_msg "cannot mount -t $(get_fstype ${dev}) -o ro ${dev} ${mountp}"
 583
 584                         doumount=1
 585                 fi
 586         fi
 587
 588         if [ "${used}" = "used" ]
 589         then
 590                 size=$(du -ks ${mountp} | cut -f1)
 591                 size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
 592         else
 593                 # free space
 594                 size="$(df -kP | grep -s ${mountp} | awk '{print $4}')"
 595         fi
 596
 597         if [ -n "${doumount}" ]
 598         then
 599                 umount "${mountp}" || log_warning_msg "cannot umount ${mountp}"
 600                 rmdir "${mountp}"
 601         fi
 602
 603         echo "${size}"
 604 }
 605
 606 load_keymap ()
 607 {
 608         # Load custom keymap
 609         if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
 610         then
 611                 loadkeys --quiet /etc/boottime.kmap.gz
 612         fi
 613 }
 614
 615 setup_loop ()
 616 {
 617         local fspath module pattern offset encryption readonly
 618         fspath=${1}
 619         module=${2}
 620         pattern=${3}
 621         offset=${4}
 622         encryption=${5}
 623         readonly=${6}
 624
 625         # the output of setup_loop is evaluated in other functions,
 626         # modprobe leaks kernel options like "libata.dma=0"
 627         # as "options libata dma=0" on stdout, causing serious
 628         # problems therefor, so instead always avoid output to stdout
 629         modprobe -q -b "${module}" 1>/dev/null
 630
 631         udevadm settle
 632
 633         for loopdev in ${pattern}
 634         do
 635                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 636                 then
 637                         dev=$(sys2dev "${loopdev}")
 638                         options=''
 639
 640                         if [ -n "${readonly}" ]
 641                         then
 642                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 643                                 then
 644                                         options="${options} -r"
 645                                 fi
 646                         fi
 647
 648                         if [ -n "${offset}" ] && [ 0 -lt "${offset}" ]
 649                         then
 650                                 options="${options} -o ${offset}"
 651                         fi
 652
 653                         if [ -z "${encryption}" ]
 654                         then
 655                                 losetup ${options} "${dev}" "${fspath}"
 656                         else
 657                                 # Loop AES encryption
 658                                 while true
 659                                 do
 660                                         load_keymap
 661
 662                                         echo -n "Enter passphrase for root filesystem: " >&6
 663                                         read -s passphrase
 664                                         echo "${passphrase}" > /tmp/passphrase
 665                                         unset passphrase
 666                                         exec 9</tmp/passphrase
 667                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 668                                         error=${?}
 669                                         exec 9<&-
 670                                         rm -f /tmp/passphrase
 671
 672                                         if [ 0 -eq ${error} ]
 673                                         then
 674                                                 unset error
 675                                                 break
 676                                         fi
 677
 678                                         echo
 679                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 680                                         read answer
 681
 682                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 683                                         then
 684                                                 unset answer
 685                                                 break
 686                                         fi
 687                                 done
 688                         fi
 689
 690                         echo "${dev}"
 691                         return 0
 692                 fi
 693         done
 694
 695         panic "No loop devices available"
 696 }
 697
 698 try_mount ()
 699 {
 700         dev="${1}"
 701         mountp="${2}"
 702         opts="${3}"
 703         fstype="${4}"
 704
 705         old_mountp="$(where_is_mounted ${dev})"
 706
 707         if [ -n "${old_mountp}" ]
 708         then
 709                 if [ "${opts}" != "ro" ]
 710                 then
 711                         mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
 712                 fi
 713
 714                 mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
 715         else
 716                 if [ -z "${fstype}" ]
 717                 then
 718                         fstype=$(get_fstype "${dev}")
 719                 fi
 720                 mount -t "${fstype}" -o "${opts}" "${dev}" "${mountp}" || \
 721                 ( echo "SKIPPING: Cannot mount ${dev} on ${mountp}, fstype=${fstype}, options=${opts}" > boot.log && return 0 )
 722         fi
 723 }
 724
 725 # Try to mount $device to the place expected by live-boot. If $device
 726 # is already mounted somewhere, move it to the expected place. If
 727 # we're only probing $device (to check if it has custom persistence)
 728 # $probe should be set, which suppresses warnings upon failure. On
 729 # success, print the mount point for $device.
 730 mount_persistence_media ()
 731 {
 732         local device probe backing old_backing fstype mount_opts
 733         device=${1}
 734         probe=${2}
 735
 736         backing="/live/persistence/$(basename ${device})"
 737
 738         mkdir -p "${backing}"
 739         old_backing="$(where_is_mounted ${device})"
 740         if [ -z "${old_backing}" ]
 741         then
 742                 fstype="$(get_fstype ${device})"
 743                 mount_opts="rw,noatime"
 744                 if [ -n "${PERSISTENCE_READONLY}" ]
 745                 then
 746                         mount_opts="ro,noatime"
 747                 fi
 748                 if mount -t "${fstype}" -o "${mount_opts}" "${device}" "${backing}" >/dev/null
 749                 then
 750                         echo ${backing}
 751                         return 0
 752                 else
 753                         [ -z "${probe}" ] && log_warning_msg "Failed to mount persistence media ${device}"
 754                         rmdir "${backing}"
 755                         return 1
 756                 fi
 757         elif [ "${backing}" != "${old_backing}" ]
 758         then
 759                 if mount --move ${old_backing} ${backing} >/dev/null
 760                 then
 761                         echo ${backing}
 762                         return 0
 763                 else
 764                         [ -z "${probe}" ] && log_warning_msg "Failed to move persistence media ${device}"
 765                         rmdir "${backing}"
 766                         return 1
 767                 fi
 768         else
 769                 # This means that $device has already been mounted on
 770                 # the place expected by live-boot, so we're done.
 771                 echo ${backing}
 772                 return 0
 773         fi
 774 }
 775
 776 close_persistence_media ()
 777 {
 778         local device backing
 779         device=${1}
 780         backing="$(where_is_mounted ${device})"
 781
 782         if [ -d "${backing}" ]
 783         then
 784                 umount "${backing}" >/dev/null 2>&1
 785                 rmdir "${backing}" >/dev/null 2>&1
 786         fi
 787
 788         if is_active_luks_mapping ${device}
 789         then
 790                 /sbin/cryptsetup luksClose ${device}
 791         fi
 792 }
 793
 794 open_luks_device ()
 795 {
 796         dev="${1}"
 797         name="$(basename ${dev})"
 798         opts="--key-file=-"
 799         if [ -n "${PERSISTENCE_READONLY}" ]
 800         then
 801                 opts="${opts} --readonly"
 802         fi
 803
 804         if /sbin/cryptsetup status "${name}" >/dev/null 2>&1
 805         then
 806                 re="^[[:space:]]*device:[[:space:]]*\([^[:space:]]*\)$"
 807                 opened_dev=$(cryptsetup status ${name} 2>/dev/null | grep "${re}" | sed "s|${re}|\1|")
 808                 if [ "${opened_dev}" = "${dev}" ]
 809                 then
 810                         luks_device="/dev/mapper/${name}"
 811                         echo ${luks_device}
 812                         return 0
 813                 else
 814                         log_warning_msg "Cannot open luks device ${dev} since ${opened_dev} already is opened with its name"
 815                         return 1
 816                 fi
 817         fi
 818
 819         load_keymap
 820
 821         while true
 822         do
 823                 /lib/cryptsetup/askpass "Enter passphrase for ${dev}: " | \
 824                         /sbin/cryptsetup -T 1 luksOpen ${dev} ${name} ${opts}
 825
 826                 if [ 0 -eq ${?} ]
 827                 then
 828                         luks_device="/dev/mapper/${name}"
 829                         echo ${luks_device}
 830                         return 0
 831                 fi
 832
 833                 echo >&6
 834                 echo -n "There was an error decrypting ${dev} ... Retry? [Y/n] " >&6
 835                 read answer
 836
 837                 if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 838                 then
 839                         return 2
 840                 fi
 841         done
 842 }
 843
 844 get_gpt_name ()
 845 {
 846     local dev
 847     dev="${1}"
 848     /sbin/blkid -s PART_ENTRY_NAME -p -o value ${dev} 2>/dev/null
 849 }
 850
 851 is_gpt_device ()
 852 {
 853     local dev
 854     dev="${1}"
 855     [ "$(/sbin/blkid -s PART_ENTRY_SCHEME -p -o value ${dev} 2>/dev/null)" = "gpt" ]
 856 }
 857
 858 probe_for_gpt_name ()
 859 {
 860         local overlays dev gpt_dev gpt_name
 861         overlays="${1}"
 862         dev="${2}"
 863
 864         gpt_dev="${dev}"
 865         if is_active_luks_mapping ${dev}
 866         then
 867                 # if $dev is an opened luks device, we need to check
 868                 # GPT stuff on the backing device
 869                 gpt_dev=$(get_luks_backing_device "${dev}")
 870         fi
 871
 872         if ! is_gpt_device ${gpt_dev}
 873         then
 874                 return
 875         fi
 876
 877         gpt_name=$(get_gpt_name ${gpt_dev})
 878         for label in ${overlays}
 879         do
 880                 if [ "${gpt_name}" = "${label}" ]
 881                 then
 882                         echo "${label}=${dev}"
 883                 fi
 884         done
 885 }
 886
 887 probe_for_fs_label ()
 888 {
 889         local overlays dev
 890         overlays="${1}"
 891         dev="${2}"
 892
 893         for label in ${overlays}
 894         do
 895                 if [ "$(/sbin/blkid -s LABEL -o value $dev 2>/dev/null)" = "${label}" ]
 896                 then
 897                         echo "${label}=${dev}"
 898                 fi
 899         done
 900 }
 901
 902 probe_for_file_name ()
 903 {
 904         local overlays dev ret backing
 905         overlays="${1}"
 906         dev="${2}"
 907
 908         ret=""
 909         backing="$(mount_persistence_media ${dev} probe)"
 910         if [ -z "${backing}" ]
 911         then
 912             return
 913         fi
 914
 915         for label in ${overlays}
 916         do
 917                 path=${backing}/${PERSISTENCE_PATH}${label}
 918                 if [ -f "${path}" ]
 919                 then
 920                         local loopdev
 921                         loopdev=$(setup_loop "${path}" "loop" "/sys/block/loop*")
 922                         ret="${ret} ${label}=${loopdev}"
 923                 fi
 924         done
 925
 926         if [ -n "${ret}" ]
 927         then
 928                 echo ${ret}
 929         else
 930                 # unmount and remove mountpoint
 931                 umount ${backing} > /dev/null 2>&1 || true
 932                 rmdir ${backing} > /dev/null 2>&1 || true
 933         fi
 934 }
 935
 936 find_persistence_media ()
 937 {
 938         # Scans devices for overlays, and returns a whitespace
 939         # separated list of how to use them. Only overlays with a partition
 940         # label or file name in ${overlays} are returned.
 941         #
 942         # When scanning a LUKS device, the user will be asked to enter the
 943         # passphrase; on failure to enter it, or if no persistence partitions
 944         # or files were found, the LUKS device is closed.
 945         #
 946         # For all other cases (overlay partition and overlay file) the
 947         # return value is "${label}=${device}", where ${device} a device that
 948         # can mount the content. In the case of an overlay file, the device
 949         # containing the file will remain mounted as a side-effect.
 950         #
 951         # No devices in ${black_listed_devices} will be scanned, and if
 952         # ${white_list_devices} is non-empty, only devices in it will be
 953         # scanned.
 954
 955         local overlays white_listed_devices ret black_listed_devices
 956         overlays="${1}"
 957         white_listed_devices="${2}"
 958         ret=""
 959
 960         black_listed_devices="$(what_is_mounted_on /live/medium)"
 961
 962         for dev in $(storage_devices "${black_listed_devices}" "${white_listed_devices}")
 963         do
 964                 local result luks_device
 965                 result=""
 966
 967                 luks_device=""
 968                 # Check if it's a luks device; we'll have to open the device
 969                 # in order to probe any filesystem it contains, like we do
 970                 # below. activate_custom_mounts() also depends on that any luks
 971                 # device already has been opened.
 972                 if is_in_comma_sep_list luks ${PERSISTENCE_ENCRYPTION} && is_luks_partition ${dev}
 973                 then
 974                         if luks_device=$(open_luks_device "${dev}")
 975                         then
 976                                 dev="${luks_device}"
 977                         else
 978                                 # skip $dev since we failed/chose not to open it
 979                                 continue
 980                         fi
 981                 elif ! is_in_comma_sep_list none ${PERSISTENCE_ENCRYPTION}
 982                 then
 983                         # skip $dev since we don't allow unencrypted storage
 984                         continue
 985                 fi
 986
 987                 # Probe for matching GPT partition names or filesystem labels
 988                 if is_in_comma_sep_list filesystem ${PERSISTENCE_STORAGE}
 989                 then
 990                         result=$(probe_for_gpt_name "${overlays}" ${dev})
 991                         if [ -n "${result}" ]
 992                         then
 993                                 ret="${ret} ${result}"
 994                                 continue
 995                         fi
 996
 997                         result=$(probe_for_fs_label "${overlays}" ${dev})
 998                         if [ -n "${result}" ]
 999                         then
1000                                 ret="${ret} ${result}"
1001                                 continue
1002                         fi
1003                 fi
1004
1005                 # Probe for files with matching name on mounted partition
1006                 if is_in_comma_sep_list file ${PERSISTENCE_STORAGE}
1007                 then
1008                         result=$(probe_for_file_name "${overlays}" ${dev})
1009                         if [ -n "${result}" ]
1010                         then
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 $rootmnt)).
1143         local src_dir dest_dir src_mask
1144
1145         # remove multiple /:s and ensure ending on /
1146         src_dir="$(trim_path ${1})/"
1147         dest_dir="$(trim_path ${2})/"
1148         src_mask="${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}" "${src_mask}"
1176                 else
1177                         final_src=${src}
1178                         if [ -n "${src_mask}" ]
1179                         then
1180                                 final_src="$(echo ${final_src} | sed "s|^${src_mask}||")"
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 ${devices}
1276         do
1277                 if [ ! -b "${device}" ]
1278                 then
1279                         continue
1280                 fi
1281
1282                 local device_name backing include_list
1283                 device_name="$(basename ${device})"
1284                 backing=$(mount_persistence_media ${device})
1285                 if [ -z "${backing}" ]
1286                 then
1287                         continue
1288                 fi
1289
1290                 if [ -r "${backing}/${persistence_list}" ]
1291                 then
1292                         include_list="${backing}/${persistence_list}"
1293                 elif [ -r "${backing}/${old_persistence_list}" ]
1294                 then
1295                         include_list="${backing}/${old_persistence_list}"
1296                 else
1297                         continue
1298                 fi
1299
1300                 if [ -n "${DEBUG}" ] && [ -e "${include_list}" ]
1301                 then
1302                         cp ${include_list} /live/persistence/${persistence_list}.${device_name}
1303                 fi
1304
1305                 while read dir options # < ${include_list}
1306                 do
1307                         if echo ${dir} | grep -qe "^[[:space:]]*\(#.*\)\?$"
1308                         then
1309                                 # skipping empty or commented lines
1310                                 continue
1311                         fi
1312
1313                         if trim_path ${dir} | grep -q -e "^[^/]" -e "^/lib" -e "^/lib/live\(/.*\)\?$" -e "^/\(.*/\)\?\.\.\?\(/.*\)\?$"
1314                         then
1315                                 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."
1316                                 continue
1317                         fi
1318
1319                         local opt_source opt_link source full_source full_dest
1320                         opt_source=""
1321                         opt_link=""
1322                         for opt in $(echo ${options} | tr ',' ' ');
1323                         do
1324                                 case "${opt}" in
1325                                         source=*)
1326                                                 opt_source=${opt#source=}
1327                                                 ;;
1328                                         link)
1329                                                 opt_link="true"
1330                                                 ;;
1331                                         union|bind)
1332                                                 ;;
1333                                         *)
1334                                                 log_warning_msg "Skipping custom mount with unkown option: ${opt}"
1335                                                 continue 2
1336                                                 ;;
1337                                 esac
1338                         done
1339
1340                         source="${dir}"
1341                         if [ -n "${opt_source}" ]
1342                         then
1343                                 if echo ${opt_source} | grep -q -e "^/" -e "^\(.*/\)\?\.\.\?\(/.*\)\?$" && [ "${opt_source}" != "." ]
1344                                 then
1345                                         log_warning_msg "Skipping unsafe custom mount with option source=${opt_source}: must be either \".\" (the media root) or a relative path w.r.t. the media root that contains neither comas, nor the special \".\" and \"..\" path components"
1346                                         continue
1347                                 else
1348                                         source="${opt_source}"
1349                                 fi
1350                         fi
1351
1352                         full_source="$(trim_path ${backing}/${source})"
1353                         full_dest="$(trim_path ${rootmnt}/${dir})"
1354                         if [ -n "${opt_link}" ]
1355                         then
1356                                 echo "${device} ${full_source} ${full_dest} ${options}" >> ${links}
1357                         else
1358                                 echo "${device} ${full_source} ${full_dest} ${options}" >> ${bindings}
1359                         fi
1360                 done < ${include_list}
1361         done
1362
1363         # We sort the list according to destination so we're sure that
1364         # we won't hide a previous mount. We also ignore duplicate
1365         # destinations in a more or less arbitrary way.
1366         [ -e "${bindings}" ] && sort -k3 -sbu ${bindings} >> ${custom_mounts} && rm ${bindings}
1367
1368         # After all mounts are considered we add symlinks so they
1369         # won't be hidden by some mount.
1370         [ -e "${links}" ] && cat ${links} >> ${custom_mounts} && rm ${links}
1371
1372         # We need to make sure that no two custom mounts have the same sources
1373         # or are nested; if that is the case, too much weird stuff can happen.
1374         local prev_source prev_dest
1375         prev_source="impossible source" # first iteration must not match
1376         prev_dest=""
1377         # This sort will ensure that a source /a comes right before a source
1378         # /a/b so we only need to look at the previous source
1379         sort -k2 -b ${custom_mounts} |
1380         while read device source dest options
1381         do
1382                 if echo ${source} | grep -qe "^${prev_source}\(/.*\)\?$"
1383                 then
1384                         panic "Two persistence mounts have the same or nested sources: ${source} on ${dest}, and ${prev_source} on ${prev_dest}"
1385                 fi
1386                 prev_source=${source}
1387                 prev_dest=${dest}
1388         done
1389 }
1390
1391 activate_custom_mounts ()
1392 {
1393         local custom_mounts used_devices
1394         custom_mounts="${1}" # the ouput from get_custom_mounts()
1395         used_devices=""
1396
1397         while read device source dest options # < ${custom_mounts}
1398         do
1399                 local opt_bind opt_link opt_union
1400                 opt_bind="true"
1401                 opt_link=""
1402                 opt_union=""
1403                 for opt in $(echo ${options} | tr ',' ' ');
1404                 do
1405                         case "${opt}" in
1406                                 bind)
1407                                         opt_bind="true"
1408                                         unset opt_link opt_union
1409                                         ;;
1410                                 link)
1411                                         opt_link="true"
1412                                         unset opt_bind opt_union
1413                                         ;;
1414                                 union)
1415                                         opt_union="true"
1416                                         unset opt_bind opt_link
1417                                         ;;
1418                         esac
1419                 done
1420
1421                 if [ -n "$(what_is_mounted_on "${dest}")" ]
1422                 then
1423                         if [ "${dest}" = "${rootmnt}" ]
1424                         then
1425                                 umount "${dest}"
1426                         else
1427                                 log_warning_msg "Skipping custom mount ${dest}: $(what_is_mounted_on "${dest}") is already mounted there"
1428                                 continue
1429                         fi
1430                 fi
1431
1432                 if [ ! -d "${dest}" ]
1433                 then
1434                         # create the destination and delete existing files in
1435                         # its path that are in the way
1436                         path="/"
1437                         for dir in $(echo ${dest} | sed -e 's|/\+| |g')
1438                         do
1439                                 path=$(trim_path ${path}/${dir})
1440                                 if [ -f ${path} ]
1441                                 then
1442                                         rm -f ${path}
1443                                 fi
1444                                 if [ ! -e ${path} ]
1445                                 then
1446                                         mkdir -p ${path}
1447                                         if echo ${path} | grep -qe "^${rootmnt}/*home/[^/]\+"
1448                                         then
1449                                                 # if ${dest} is in /home try fixing proper ownership by assuming that the intended user is the first, which is usually the case
1450                                                 # FIXME: this should really be handled by live-config since we don't know for sure which uid a certain user has until then
1451                                                 chown 1000:1000 ${path}
1452                                         fi
1453                                 fi
1454                         done
1455                 fi
1456
1457                 # if ${source} doesn't exist on our persistence media
1458                 # we bootstrap it with $dest from the live filesystem.
1459                 # this both makes sense and is critical if we're
1460                 # dealing with /etc or other system dir.
1461                 if [ ! -d "${source}" ]
1462                 then
1463                         if [ -n "${PERSISTENCE_READONLY}" ]
1464                         then
1465                                 continue
1466                         elif [ -n "${opt_union}" ] || [ -n "${opt_link}" ]
1467                         then
1468                                 # unions and don't need to be bootstrapped
1469                                 # link dirs can't be bootstrapped in a sensible way
1470                                 mkdir -p "${source}"
1471                                 chown_ref "${dest}" "${source}"
1472                                 chmod_ref "${dest}" "${source}"
1473                         elif [ -n "${opt_bind}" ]
1474                         then
1475                                 # ensure that $dest is not copied *into* $source
1476                                 mkdir -p "$(dirname ${source})"
1477                                 cp -a "${dest}" "${source}"
1478                         fi
1479                 fi
1480
1481                 # XXX: If CONFIG_AUFS_ROBR is added to the Debian kernel we can
1482                 # ignore the loop below and set rootfs_dest_backing=$dest
1483                 local rootfs_dest_backing
1484                 rootfs_dest_backing=""
1485                 if [ -n "${opt_link}" ]
1486                 then
1487                         for d in /live/rootfs/*
1488                         do
1489                                 if [ -n "${rootmnt}" ]
1490                                 then
1491                                         fs="${d}/$(echo ${dest} | sed -e "s|${rootmnt}||")"
1492                                 else
1493                                         fs="${d}/${dest}"
1494                                 fi
1495                                 if [ -d "${fs}" ]
1496                                 then
1497                                         rootfs_dest_backing="${rootfs_dest_backing} ${fs}"
1498                                 fi
1499                         done
1500                 fi
1501
1502                 local cow_dir links_source
1503                 if [ -n "${opt_link}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1504                 then
1505                         link_files ${source} ${dest} ${rootmnt}
1506                 elif [ -n "${opt_link}" ] && [ -n "${PERSISTENCE_READONLY}" ]
1507                 then
1508                         mkdir -p ${rootmnt}/lib/live/mount/persistence
1509                         links_source=$(mktemp -d ${rootmnt}/lib/live/mount/persistence/links-source-XXXXXX)
1510                         chown_ref ${source} ${links_source}
1511                         chmod_ref ${source} ${links_source}
1512                         # We put the cow dir in the below strange place to
1513                         # make it absolutely certain that the link source
1514                         # has its own directory and isn't nested with some
1515                         # other custom mount (if so that mount's files would
1516                         # be linked, causing breakage.
1517                         cow_dir="/live/overlay/lib/live/mount/persistence/$(basename ${links_source})"
1518                         mkdir -p ${cow_dir}
1519                         chown_ref "${source}" "${cow_dir}"
1520                         chmod_ref "${source}" "${cow_dir}"
1521                         do_union ${links_source} ${cow_dir} ${source} ${rootfs_dest_backing}
1522                         link_files ${links_source} ${dest} ${rootmnt}
1523                 elif [ -n "${opt_union}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1524                 then
1525                         do_union ${dest} ${source} ${rootfs_dest_backing}
1526                 elif [ -n "${opt_bind}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1527                 then
1528                         mount --bind "${source}" "${dest}"
1529                 elif [ -n "${opt_bind}" -o -n "${opt_union}" ] && [ -n "${PERSISTENCE_READONLY}" ]
1530                 then
1531                         # bind-mount and union mount are handled the same
1532                         # in read-only mode, but note that rootfs_dest_backing
1533                         # is non-empty (and necessary) only for unions
1534                         cow_dir="/live/overlay/${dest}"
1535                         if [ -e "${cow_dir}" ] && [ -z "${opt_link}" ]
1536                         then
1537                                 # If an earlier custom mount has files here
1538                                 # it will "block" the current mount's files
1539                                 # which is undesirable
1540                                 rm -rf "${cow_dir}"
1541                         fi
1542                         mkdir -p ${cow_dir}
1543                         chown_ref "${source}" "${cow_dir}"
1544                         chmod_ref "${source}" "${cow_dir}"
1545                         do_union ${dest} ${cow_dir} ${source} ${rootfs_dest_backing}
1546                 fi
1547
1548                 PERSISTENCE_IS_ON="1"
1549                 export PERSISTENCE_IS_ON
1550
1551                 if echo ${used_devices} | grep -qve "^\(.* \)\?${device}\( .*\)\?$"
1552                 then
1553                         used_devices="${used_devices} ${device}"
1554                 fi
1555         done < ${custom_mounts}
1556
1557         echo ${used_devices}
1558 }
1559
1560 is_mountpoint ()
1561 {
1562         directory="$1"
1563
1564         [ $(stat -fc%d:%D "${directory}") != $(stat -fc%d:%D "${directory}/..") ]
1565 }