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 ${1} ?
  68         local pattern="${1}"
  69
  70         if [ "$(echo ${pattern})" != "${pattern}" ]
  71         then
  72                 return 0
  73         fi
  74
  75         return 1
  76 }
  77
  78 mount_images_in_directory ()
  79 {
  80         directory="${1}"
  81         rootmnt="${2}"
  82         mac="${3}"
  83
  84         if match_files_in_dir "${directory}/${LIVE_MEDIA_PATH}/*.squashfs" ||
  85                 match_files_in_dir "${directory}/${LIVE_MEDIA_PATH}/*.ext2" ||
  86                 match_files_in_dir "${directory}/${LIVE_MEDIA_PATH}/*.ext3" ||
  87                 match_files_in_dir "${directory}/${LIVE_MEDIA_PATH}/*.ext4" ||
  88                 match_files_in_dir "${directory}/${LIVE_MEDIA_PATH}/*.jffs2" ||
  89                 match_files_in_dir "${directory}/${LIVE_MEDIA_PATH}/*.dir"
  90         then
  91                 [ -n "${mac}" ] && adddirectory="${directory}/${LIVE_MEDIA_PATH}/${mac}"
  92                 setup_unionfs "${directory}/${LIVE_MEDIA_PATH}" "${rootmnt}" "${adddirectory}"
  93         else
  94                 panic "No supported filesystem images found at /${LIVE_MEDIA_PATH}."
  95         fi
  96 }
  97
  98 is_nice_device ()
  99 {
 100         sysfs_path="${1#/sys}"
 101
 102         if [ -e /lib/udev/path_id ]
 103         then
 104                 # squeeze
 105                 PATH_ID="/lib/udev/path_id"
 106         else
 107                 # wheezy/sid (udev >= 174)
 108                 PATH_ID="/sbin/udevadm test-builtin path_id"
 109         fi
 110
 111         if ${PATH_ID} "${sysfs_path}" | egrep -q "ID_PATH=(usb|pci-[^-]*-(ide|sas|scsi|usb|virtio)|platform-sata_mv|platform-orion-ehci|platform-mmc|platform-mxsdhci)"
 112         then
 113                 return 0
 114         elif echo "${sysfs_path}" | grep -q '^/block/vd[a-z]$'
 115         then
 116                 return 0
 117         elif echo ${sysfs_path} | grep -q "^/block/dm-"
 118         then
 119                 return 0
 120         elif echo ${sysfs_path} | grep -q "^/block/mtdblock"
 121         then
 122                 return 0
 123         fi
 124
 125         return 1
 126 }
 127
 128 check_dev ()
 129 {
 130         sysdev="${1}"
 131         devname="${2}"
 132         skip_uuid_check="${3}"
 133
 134         # support for fromiso=.../isofrom=....
 135         if [ -n "$FROMISO" ]
 136         then
 137                 ISO_DEVICE=$(dirname $FROMISO)
 138                 if ! [ -b $ISO_DEVICE ]
 139                 then
 140                         # to support unusual device names like /dev/cciss/c0d0p1
 141                         # as well we have to identify the block device name, let's
 142                         # do that for up to 15 levels
 143                         i=15
 144                         while [ -n "$ISO_DEVICE" ] && [ "$i" -gt 0 ]
 145                         do
 146                                 ISO_DEVICE=$(dirname ${ISO_DEVICE})
 147                                 [ -b "$ISO_DEVICE" ] && break
 148                                 i=$(($i -1))
 149                         done
 150                 fi
 151
 152                 if [ "$ISO_DEVICE" = "/" ]
 153                 then
 154                         echo "Warning: device for bootoption fromiso= ($FROMISO) not found.">>/boot.log
 155                 else
 156                         fs_type=$(get_fstype "${ISO_DEVICE}")
 157                         if is_supported_fs ${fs_type}
 158                         then
 159                                 mkdir /live/fromiso
 160                                 mount -t $fs_type "$ISO_DEVICE" /live/fromiso
 161                                 ISO_NAME="$(echo $FROMISO | sed "s|$ISO_DEVICE||")"
 162                                 loopdevname=$(setup_loop "/live/fromiso/${ISO_NAME}" "loop" "/sys/block/loop*" "" '')
 163                                 devname="${loopdevname}"
 164                         else
 165                                 echo "Warning: unable to mount $ISO_DEVICE." >>/boot.log
 166                         fi
 167                 fi
 168         fi
 169
 170         if [ -z "${devname}" ]
 171         then
 172                 devname=$(sys2dev "${sysdev}")
 173         fi
 174
 175         if [ -d "${devname}" ]
 176         then
 177                 mount -o bind "${devname}" $mountpoint || continue
 178
 179                 if is_live_path $mountpoint
 180                 then
 181                         echo $mountpoint
 182                         return 0
 183                 else
 184                         umount $mountpoint
 185                 fi
 186         fi
 187
 188         IFS=","
 189         for device in ${devname}
 190         do
 191                 case "$device" in
 192                         *mapper*)
 193                                 # Adding lvm support
 194                                 if [ -x /scripts/local-top/lvm2 ]
 195                                 then
 196                                         ROOT="$device" resume="" /scripts/local-top/lvm2
 197                                 fi
 198                                 ;;
 199
 200                         /dev/md*)
 201                                 # Adding raid support
 202                                 if [ -x /scripts/local-top/mdadm ]
 203                                 then
 204                                         cp /conf/conf.d/md /conf/conf.d/md.orig
 205                                         echo "MD_DEVS=$device " >> /conf/conf.d/md
 206                                         /scripts/local-top/mdadm
 207                                         mv /conf/conf.d/md.orig /conf/conf.d/md
 208                                 fi
 209                                 ;;
 210                 esac
 211         done
 212         unset IFS
 213
 214         [ -n "$device" ] && devname="$device"
 215
 216         [ -e "$devname" ] || continue
 217
 218         if [ -n "${LIVE_MEDIA_OFFSET}" ]
 219         then
 220                 loopdevname=$(setup_loop "${devname}" "loop" "/sys/block/loop*" "${LIVE_MEDIA_OFFSET}" '')
 221                 devname="${loopdevname}"
 222         fi
 223
 224         fstype=$(get_fstype "${devname}")
 225
 226         if is_supported_fs ${fstype}
 227         then
 228                 devuid=$(blkid -o value -s UUID "$devname")
 229                 [ -n "$devuid" ] && grep -qs "\<$devuid\>" $tried && continue
 230                 mount -t ${fstype} -o ro,noatime "${devname}" ${mountpoint} || continue
 231                 [ -n "$devuid" ] && echo "$devuid" >> $tried
 232
 233                 if [ -n "${FINDISO}" ]
 234                 then
 235                         if [ -f ${mountpoint}/${FINDISO} ]
 236                         then
 237                                 umount ${mountpoint}
 238                                 mkdir -p /live/findiso
 239                                 mount -t ${fstype} -o ro,noatime "${devname}" /live/findiso
 240                                 loopdevname=$(setup_loop "/live/findiso/${FINDISO}" "loop" "/sys/block/loop*" 0 "")
 241                                 devname="${loopdevname}"
 242                                 mount -t iso9660 -o ro,noatime "${devname}" ${mountpoint}
 243                         else
 244                                 umount ${mountpoint}
 245                         fi
 246                 fi
 247
 248                 if is_live_path ${mountpoint} && \
 249                         ([ "${skip_uuid_check}" ] || matches_uuid ${mountpoint})
 250                 then
 251                         echo ${mountpoint}
 252                         return 0
 253                 else
 254                         umount ${mountpoint} 2>/dev/null
 255                 fi
 256         fi
 257
 258         if [ -n "${LIVE_MEDIA_OFFSET}" ]
 259         then
 260                 losetup -d "${loopdevname}"
 261         fi
 262
 263         return 1
 264 }
 265
 266 find_livefs ()
 267 {
 268         timeout="${1}"
 269
 270         # don't start autodetection before timeout has expired
 271         if [ -n "${LIVE_MEDIA_TIMEOUT}" ]
 272         then
 273                 if [ "${timeout}" -lt "${LIVE_MEDIA_TIMEOUT}" ]
 274                 then
 275                         return 1
 276                 fi
 277         fi
 278
 279         # first look at the one specified in the command line
 280         case "${LIVE_MEDIA}" in
 281                 removable-usb)
 282                         for sysblock in $(removable_usb_dev "sys")
 283                         do
 284                                 for dev in $(subdevices "${sysblock}")
 285                                 do
 286                                         if check_dev "${dev}"
 287                                         then
 288                                                 return 0
 289                                         fi
 290                                 done
 291                         done
 292                         return 1
 293                         ;;
 294
 295                 removable)
 296                         for sysblock in $(removable_dev "sys")
 297                         do
 298                                 for dev in $(subdevices "${sysblock}")
 299                                 do
 300                                         if check_dev "${dev}"
 301                                         then
 302                                                 return 0
 303                                         fi
 304                                 done
 305                         done
 306                         return 1
 307                         ;;
 308
 309                 *)
 310                         if [ ! -z "${LIVE_MEDIA}" ]
 311                         then
 312                                 if check_dev "null" "${LIVE_MEDIA}" "skip_uuid_check"
 313                                 then
 314                                         return 0
 315                                 fi
 316                         fi
 317                         ;;
 318         esac
 319
 320         # or do the scan of block devices
 321         # prefer removable devices over non-removable devices, so scan them first
 322         devices_to_scan="$(removable_dev 'sys') $(non_removable_dev 'sys')"
 323
 324         for sysblock in $devices_to_scan
 325         do
 326                 devname=$(sys2dev "${sysblock}")
 327                 [ -e "$devname" ] || continue
 328                 fstype=$(get_fstype "${devname}")
 329
 330                 if /lib/udev/cdrom_id ${devname} > /dev/null
 331                 then
 332                         if check_dev "null" "${devname}"
 333                         then
 334                                 return 0
 335                         fi
 336                 elif is_nice_device "${sysblock}"
 337                 then
 338                         for dev in $(subdevices "${sysblock}")
 339                         do
 340                                 if check_dev "${dev}"
 341                                 then
 342                                         return 0
 343                                 fi
 344                         done
 345                 elif [ "${fstype}" = "squashfs" -o \
 346                         "${fstype}" = "btrfs" -o \
 347                         "${fstype}" = "ext2" -o \
 348                         "${fstype}" = "ext3" -o \
 349                         "${fstype}" = "ext4" -o \
 350                         "${fstype}" = "jffs2" ]
 351                 then
 352                         # This is an ugly hack situation, the block device has
 353                         # an image directly on it.  It's hopefully
 354                         # live-boot, so take it and run with it.
 355                         ln -s "${devname}" "${devname}.${fstype}"
 356                         echo "${devname}.${fstype}"
 357                         return 0
 358                 fi
 359         done
 360
 361         return 1
 362 }
 363
 364 really_export ()
 365 {
 366         STRING="${1}"
 367         VALUE="$(eval echo -n \${$STRING})"
 368
 369         if [ -f /live.vars ] && grep -sq "export ${STRING}" /live.vars
 370         then
 371                 sed -i -e 's/\('${STRING}'=\).*$/\1'${VALUE}'/' /live.vars
 372         else
 373                 echo "export ${STRING}=\"${VALUE}\"" >> /live.vars
 374         fi
 375
 376         eval export "${STRING}"="${VALUE}"
 377 }
 378
 379 is_in_list_separator_helper ()
 380 {
 381         local sep=${1}
 382         shift
 383         local element=${1}
 384         shift
 385         local list=${*}
 386         echo ${list} | grep -qe "^\(.*${sep}\)\?${element}\(${sep}.*\)\?$"
 387 }
 388
 389 is_in_space_sep_list ()
 390 {
 391         local element=${1}
 392         shift
 393         is_in_list_separator_helper "[[:space:]]" "${element}" "${*}"
 394 }
 395
 396 is_in_comma_sep_list ()
 397 {
 398         local element=${1}
 399         shift
 400         is_in_list_separator_helper "," "${element}" "${*}"
 401 }
 402
 403 sys2dev ()
 404 {
 405         sysdev=${1#/sys}
 406         echo "/dev/$($udevinfo -q name -p ${sysdev} 2>/dev/null|| echo ${sysdev##*/})"
 407 }
 408
 409 subdevices ()
 410 {
 411         sysblock=${1}
 412         r=""
 413
 414         for dev in "${sysblock}"/* "${sysblock}"
 415         do
 416                 if [ -e "${dev}/dev" ]
 417                 then
 418                         r="${r} ${dev}"
 419                 fi
 420         done
 421
 422         echo ${r}
 423 }
 424
 425 storage_devices()
 426 {
 427         black_listed_devices="${1}"
 428         white_listed_devices="${2}"
 429
 430         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "loop|ram|fd")
 431         do
 432                 fulldevname=$(sys2dev "${sysblock}")
 433
 434                 if is_in_space_sep_list ${fulldevname} ${black_listed_devices} || \
 435                         [ -n "${white_listed_devices}" ] && \
 436                         ! is_in_space_sep_list ${fulldevname} ${white_listed_devices}
 437                 then
 438                         # skip this device entirely
 439                         continue
 440                 fi
 441
 442                 for dev in $(subdevices "${sysblock}")
 443                 do
 444                         devname=$(sys2dev "${dev}")
 445
 446                         if is_in_space_sep_list ${devname} ${black_listed_devices}
 447                         then
 448                                 # skip this subdevice
 449                                 continue
 450                         else
 451                                 echo "${devname}"
 452                         fi
 453                 done
 454         done
 455 }
 456
 457 is_supported_fs ()
 458 {
 459         fstype="${1}"
 460
 461         # Validate input first
 462         if [ -z "${fstype}" ]
 463         then
 464                 return 1
 465         fi
 466
 467         # Try to look if it is already supported by the kernel
 468         if grep -q ${fstype} /proc/filesystems
 469         then
 470                 return 0
 471         else
 472                 # Then try to add support for it the gentle way using the initramfs capabilities
 473                 modprobe ${fstype}
 474                 if grep -q ${fstype} /proc/filesystems
 475                 then
 476                         return 0
 477                 # Then try the hard way if /root is already reachable
 478                 else
 479                         kmodule="/root/lib/modules/`uname -r`/${fstype}/${fstype}.ko"
 480                         if [ -e "${kmodule}" ]
 481                         then
 482                                 insmod "${kmodule}"
 483                                 if grep -q ${fstype} /proc/filesystems
 484                                 then
 485                                         return 0
 486                                 fi
 487                         fi
 488                 fi
 489         fi
 490
 491         return 1
 492 }
 493
 494 get_fstype ()
 495 {
 496         /sbin/blkid -s TYPE -o value $1 2>/dev/null
 497 }
 498
 499 where_is_mounted ()
 500 {
 501         device=${1}
 502         # return first found
 503         grep -m1 "^${device} " /proc/mounts | cut -f2 -d ' '
 504 }
 505
 506 trim_path ()
 507 {
 508         # remove all unnecessary /:s in the path, including last one (except
 509         # if path is just "/")
 510         echo ${1} | sed 's|//\+|/|g' | sed 's|^\(.*[^/]\)/$|\1|'
 511 }
 512
 513 what_is_mounted_on ()
 514 {
 515         local dir="$(trim_path ${1})"
 516         grep -m1 "^[^ ]\+ ${dir} " /proc/mounts | cut -d' ' -f1
 517 }
 518
 519 chown_ref ()
 520 {
 521         local reference="${1}"
 522         shift
 523         local targets=${@}
 524         local owner=$(stat -c %u:%g "${reference}")
 525         chown -h ${owner} ${targets}
 526 }
 527
 528 chmod_ref ()
 529 {
 530         local reference="${1}"
 531         shift
 532         local targets=${@}
 533         local rights=$(stat -c %a "${reference}")
 534         chmod ${rights} ${targets}
 535 }
 536
 537 lastline ()
 538 {
 539         while read lines
 540         do
 541                 line=${lines}
 542         done
 543
 544         echo "${line}"
 545 }
 546
 547 base_path ()
 548 {
 549         testpath="${1}"
 550         mounts="$(awk '{print $2}' /proc/mounts)"
 551         testpath="$(busybox realpath ${testpath})"
 552
 553         while true
 554         do
 555                 if echo "${mounts}" | grep -qs "^${testpath}"
 556                 then
 557                         set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
 558                         echo ${1}
 559                         break
 560                 else
 561                         testpath=$(dirname $testpath)
 562                 fi
 563         done
 564 }
 565
 566 fs_size ()
 567 {
 568         # Returns used/free fs kbytes + 5% more
 569         # You could pass a block device as ${1} or the mount point as ${2}
 570
 571         dev="${1}"
 572         mountp="${2}"
 573         used="${3}"
 574
 575         if [ -z "${mountp}" ]
 576         then
 577                 mountp="$(where_is_mounted ${dev})"
 578
 579                 if [ -z "${mountp}" ]
 580                 then
 581                         mountp="/mnt/tmp_fs_size"
 582
 583                         mkdir -p "${mountp}"
 584                         mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}" || log_warning_msg "cannot mount -t $(get_fstype ${dev}) -o ro ${dev} ${mountp}"
 585
 586                         doumount=1
 587                 fi
 588         fi
 589
 590         if [ "${used}" = "used" ]
 591         then
 592                 size=$(du -ks ${mountp} | cut -f1)
 593                 size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
 594         else
 595                 # free space
 596                 size="$(df -k | grep -s ${mountp} | awk '{print $4}')"
 597         fi
 598
 599         if [ -n "${doumount}" ]
 600         then
 601                 umount "${mountp}" || log_warning_msg "cannot umount ${mountp}"
 602                 rmdir "${mountp}"
 603         fi
 604
 605         echo "${size}"
 606 }
 607
 608 load_keymap ()
 609 {
 610         # Load custom keymap
 611         if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
 612         then
 613                 loadkeys /etc/boottime.kmap.gz
 614         fi
 615 }
 616
 617 setup_loop ()
 618 {
 619         local fspath=${1}
 620         local module=${2}
 621         local pattern=${3}
 622         local offset=${4}
 623         local encryption=${5}
 624         local readonly=${6}
 625
 626         # the output of setup_loop is evaluated in other functions,
 627         # modprobe leaks kernel options like "libata.dma=0"
 628         # as "options libata dma=0" on stdout, causing serious
 629         # problems therefor, so instead always avoid output to stdout
 630         modprobe -q -b "${module}" 1>/dev/null
 631
 632         udevadm settle
 633
 634         for loopdev in ${pattern}
 635         do
 636                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 637                 then
 638                         dev=$(sys2dev "${loopdev}")
 639                         options=''
 640
 641                         if [ -n "${readonly}" ]
 642                         then
 643                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 644                                 then
 645                                         options="${options} -r"
 646                                 fi
 647                         fi
 648
 649                         if [ -n "${offset}" ] && [ 0 -lt "${offset}" ]
 650                         then
 651                                 options="${options} -o ${offset}"
 652                         fi
 653
 654                         if [ -z "${encryption}" ]
 655                         then
 656                                 losetup ${options} "${dev}" "${fspath}"
 657                         else
 658                                 # Loop AES encryption
 659                                 while true
 660                                 do
 661                                         load_keymap
 662
 663                                         echo -n "Enter passphrase for root filesystem: " >&6
 664                                         read -s passphrase
 665                                         echo "${passphrase}" > /tmp/passphrase
 666                                         unset passphrase
 667                                         exec 9</tmp/passphrase
 668                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 669                                         error=${?}
 670                                         exec 9<&-
 671                                         rm -f /tmp/passphrase
 672
 673                                         if [ 0 -eq ${error} ]
 674                                         then
 675                                                 unset error
 676                                                 break
 677                                         fi
 678
 679                                         echo
 680                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 681                                         read answer
 682
 683                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 684                                         then
 685                                                 unset answer
 686                                                 break
 687                                         fi
 688                                 done
 689                         fi
 690
 691                         echo "${dev}"
 692                         return 0
 693                 fi
 694         done
 695
 696         panic "No loop devices available"
 697 }
 698
 699 try_mount ()
 700 {
 701         dev="${1}"
 702         mountp="${2}"
 703         opts="${3}"
 704         fstype="${4}"
 705
 706         old_mountp="$(where_is_mounted ${dev})"
 707
 708         if [ -n "${old_mountp}" ]
 709         then
 710                 if [ "${opts}" != "ro" ]
 711                 then
 712                         mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
 713                 fi
 714
 715                 mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
 716         else
 717                 if [ -z "${fstype}" ]
 718                 then
 719                         fstype=$(get_fstype "${dev}")
 720                 fi
 721                 mount -t "${fstype}" -o "${opts}" "${dev}" "${mountp}" || \
 722                 ( echo "SKIPPING: Cannot mount ${dev} on ${mountp}, fstype=${fstype}, options=${opts}" > boot.log && return 0 )
 723         fi
 724 }
 725
 726 mount_persistence_media ()
 727 {
 728         local device=${1}
 729         local probe=${2}
 730
 731         local backing="/live/persistence/$(basename ${device})"
 732
 733         mkdir -p "${backing}"
 734         local old_backing="$(where_is_mounted ${device})"
 735         if [ -z "${old_backing}" ]
 736         then
 737                 local fstype="$(get_fstype ${device})"
 738                 local mount_opts="rw,noatime"
 739                 if [ -n "${PERSISTENCE_READONLY}" ]
 740                 then
 741                         mount_opts="ro,noatime"
 742                 fi
 743                 if mount -t "${fstype}" -o "${mount_opts}" "${device}" "${backing}" >/dev/null
 744                 then
 745                         echo ${backing}
 746                         return 0
 747                 else
 748                         [ -z "${probe}" ] && log_warning_msg "Failed to mount persistence media ${device}"
 749                         rmdir "${backing}"
 750                         return 1
 751                 fi
 752         elif [ "${backing}" != "${old_backing}" ]
 753         then
 754                 if mount --move ${old_backing} ${backing} >/dev/null
 755                 then
 756                         echo ${backing}
 757                         return 0
 758                 else
 759                         [ -z "${probe}" ] && log_warning_msg "Failed to move persistence media ${device}"
 760                         rmdir "${backing}"
 761                         return 1
 762                 fi
 763         fi
 764         return 0
 765 }
 766
 767 close_persistence_media ()
 768 {
 769         local device=${1}
 770         local backing="$(where_is_mounted ${device})"
 771
 772         if [ -d "${backing}" ]
 773         then
 774                 umount "${backing}" >/dev/null 2>&1
 775                 rmdir "${backing}" >/dev/null 2>&1
 776         fi
 777
 778         if is_active_luks_mapping ${device}
 779         then
 780                 /sbin/cryptsetup luksClose ${device}
 781         fi
 782 }
 783
 784 open_luks_device ()
 785 {
 786         dev="${1}"
 787         name="$(basename ${dev})"
 788         opts="--key-file=-"
 789         if [ -n "${PERSISTENCE_READONLY}" ]
 790         then
 791                 opts="${opts} --readonly"
 792         fi
 793
 794         if /sbin/cryptsetup status "${name}" >/dev/null 2>&1
 795         then
 796                 re="^[[:space:]]*device:[[:space:]]*\([^[:space:]]*\)$"
 797                 opened_dev=$(cryptsetup status ${name} 2>/dev/null | grep "${re}" | sed "s|${re}|\1|")
 798                 if [ "${opened_dev}" = "${dev}" ]
 799                 then
 800                         luks_device="/dev/mapper/${name}"
 801                         echo ${luks_device}
 802                         return 0
 803                 else
 804                         log_warning_msg "Cannot open luks device ${dev} since ${opened_dev} already is opened with its name"
 805                         return 1
 806                 fi
 807         fi
 808
 809         load_keymap
 810
 811         while true
 812         do
 813                 /lib/cryptsetup/askpass "Enter passphrase for ${dev}: " | \
 814                         /sbin/cryptsetup -T 1 luksOpen ${dev} ${name} ${opts}
 815
 816                 if [ 0 -eq ${?} ]
 817                 then
 818                         luks_device="/dev/mapper/${name}"
 819                         echo ${luks_device}
 820                         return 0
 821                 fi
 822
 823                 echo >&6
 824                 echo -n "There was an error decrypting ${dev} ... Retry? [Y/n] " >&6
 825                 read answer
 826
 827                 if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 828                 then
 829                         return 2
 830                 fi
 831         done
 832 }
 833
 834 get_gpt_name ()
 835 {
 836     local dev="${1}"
 837     /sbin/blkid -s PART_ENTRY_NAME -p -o value ${dev} 2>/dev/null
 838 }
 839
 840 is_gpt_device ()
 841 {
 842     local dev="${1}"
 843     [ "$(/sbin/blkid -s PART_ENTRY_SCHEME -p -o value ${dev} 2>/dev/null)" = "gpt" ]
 844 }
 845
 846 probe_for_gpt_name ()
 847 {
 848         local overlays="${1}"
 849         local dev="${2}"
 850
 851         local gpt_dev="${dev}"
 852         if is_active_luks_mapping ${dev}
 853         then
 854                 # if $dev is an opened luks device, we need to check
 855                 # GPT stuff on the backing device
 856                 gpt_dev=$(get_luks_backing_device "${dev}")
 857         fi
 858
 859         if ! is_gpt_device ${gpt_dev}
 860         then
 861                 return
 862         fi
 863
 864         local gpt_name=$(get_gpt_name ${gpt_dev})
 865         for label in ${overlays}
 866         do
 867                 if [ "${gpt_name}" = "${label}" ]
 868                 then
 869                         echo "${label}=${dev}"
 870                 fi
 871         done
 872 }
 873
 874 probe_for_fs_label ()
 875 {
 876         local overlays="${1}"
 877         local dev="${2}"
 878
 879         for label in ${overlays}
 880         do
 881                 if [ "$(/sbin/blkid -s LABEL -o value $dev 2>/dev/null)" = "${label}" ]
 882                 then
 883                         echo "${label}=${dev}"
 884                 fi
 885         done
 886 }
 887
 888 probe_for_file_name ()
 889 {
 890         local overlays="${1}"
 891         local dev="${2}"
 892
 893         local ret=""
 894         local 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 "${path}" ]
 904                 then
 905                         local loopdev=$(setup_loop "${path}" "loop" "/sys/block/loop*")
 906                         ret="${ret} ${label}=${loopdev}"
 907                 fi
 908         done
 909
 910         if [ -n "${ret}" ]
 911         then
 912                 echo ${ret}
 913         else
 914                 # unmount and remove mountpoint
 915                 umount ${backing} > /dev/null 2>&1 || true
 916                 rmdir ${backing} > /dev/null 2>&1 || true
 917         fi
 918 }
 919
 920 find_persistence_media ()
 921 {
 922         # Scans devices for overlays, and returns a whitespace
 923         # separated list of how to use them. Only overlays with a partition
 924         # label or file name in ${overlays} are returned.
 925         #
 926         # When scanning a LUKS device, the user will be asked to enter the
 927         # passphrase; on failure to enter it, or if no persistence partitions
 928         # or files were found, the LUKS device is closed.
 929         #
 930         # For all other cases (overlay partition and overlay file) the
 931         # return value is "${label}=${device}", where ${device} a device that
 932         # can mount the content. In the case of an overlay file, the device
 933         # containing the file will remain mounted as a side-effect.
 934         #
 935         # No devices in ${black_listed_devices} will be scanned, and if
 936         # ${white_list_devices} is non-empty, only devices in it will be
 937         # scanned.
 938
 939         local overlays="${1}"
 940         local white_listed_devices="${2}"
 941         local ret=""
 942
 943         local black_listed_devices="$(what_is_mounted_on /live/image)"
 944
 945         for dev in $(storage_devices "${black_listed_devices}" "${white_listed_devices}")
 946         do
 947                 local result=""
 948
 949                 local luks_device=""
 950                 # Check if it's a luks device; we'll have to open the device
 951                 # in order to probe any filesystem it contains, like we do
 952                 # below. activate_custom_mounts() also depends on that any luks
 953                 # device already has been opened.
 954                 if is_in_comma_sep_list luks ${PERSISTENCE_ENCRYPTION} && is_luks_partition ${dev}
 955                 then
 956                         if luks_device=$(open_luks_device "${dev}")
 957                         then
 958                                 dev="${luks_device}"
 959                         else
 960                                 # skip $dev since we failed/chose not to open it
 961                                 continue
 962                         fi
 963                 elif ! is_in_comma_sep_list none ${PERSISTENCE_ENCRYPTION}
 964                 then
 965                         # skip $dev since we don't allow unencrypted storage
 966                         continue
 967                 fi
 968
 969                 # Probe for matching GPT partition names or filesystem labels
 970                 if is_in_comma_sep_list filesystem ${PERSISTENCE_STORAGE}
 971                 then
 972                         result=$(probe_for_gpt_name "${overlays}" ${dev})
 973                         if [ -n "${result}" ]
 974                         then
 975                                 ret="${ret} ${result}"
 976                                 continue
 977                         fi
 978
 979                         result=$(probe_for_fs_label "${overlays}" ${dev})
 980                         if [ -n "${result}" ]
 981                         then
 982                                 ret="${ret} ${result}"
 983                                 continue
 984                         fi
 985                 fi
 986
 987                 # Probe for files with matching name on mounted partition
 988                 if is_in_comma_sep_list file ${PERSISTENCE_STORAGE}
 989                 then
 990                         result=$(probe_for_file_name "${overlays}" ${dev})
 991                         if [ -n "${result}" ]
 992                         then
 993                                 ret="${ret} ${result}"
 994                                 continue
 995                         fi
 996                 fi
 997
 998                 # Close luks device if it isn't used
 999                 if [ -z "${result}" ] && [ -n "${luks_device}" ] && is_active_luks_mapping "${luks_device}"
1000                 then
1001                         /sbin/cryptsetup luksClose "${luks_device}"
1002                 fi
1003         done
1004
1005         if [ -n "${ret}" ]
1006         then
1007                 echo ${ret}
1008         fi
1009 }
1010
1011 get_mac ()
1012 {
1013         mac=""
1014
1015         for adaptor in /sys/class/net/*
1016         do
1017                 status="$(cat ${adaptor}/iflink)"
1018
1019                 if [ "${status}" -eq 2 ]
1020                 then
1021                         mac="$(cat ${adaptor}/address)"
1022                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
1023                 fi
1024         done
1025
1026         echo ${mac}
1027 }
1028
1029 is_luks_partition ()
1030 {
1031         device="${1}"
1032         /sbin/cryptsetup isLuks "${device}" 1>/dev/null 2>&1
1033 }
1034
1035 is_active_luks_mapping ()
1036 {
1037         device="${1}"
1038         /sbin/cryptsetup status "${device}" 1>/dev/null 2>&1
1039 }
1040
1041 get_luks_backing_device ()
1042 {
1043         device=${1}
1044         cryptsetup status ${device} 2> /dev/null | \
1045                 awk '{if ($1 == "device:") print $2}'
1046 }
1047
1048 removable_dev ()
1049 {
1050         output_format="${1}"
1051         want_usb="${2}"
1052         ret=
1053
1054         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
1055         do
1056                 dev_ok=
1057                 if [ "$(cat ${sysblock}/removable)" = "1" ]
1058                 then
1059                         if [ -z "${want_usb}" ]
1060                         then
1061                                 dev_ok="true"
1062                         else
1063                                 if readlink ${sysblock} | grep -q usb
1064                                 then
1065                                         dev_ok="true"
1066                                 fi
1067                         fi
1068                 fi
1069
1070                 if [ "${dev_ok}" = "true" ]
1071                 then
1072                         case "${output_format}" in
1073                                 sys)
1074                                         ret="${ret} ${sysblock}"
1075                                         ;;
1076                                 *)
1077                                         devname=$(sys2dev "${sysblock}")
1078                                         ret="${ret} ${devname}"
1079                                         ;;
1080                         esac
1081                 fi
1082         done
1083
1084         echo "${ret}"
1085 }
1086
1087 removable_usb_dev ()
1088 {
1089         output_format="${1}"
1090
1091         removable_dev "${output_format}" "want_usb"
1092 }
1093
1094 non_removable_dev ()
1095 {
1096         output_format="${1}"
1097         ret=
1098
1099         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
1100         do
1101                 if [ "$(cat ${sysblock}/removable)" = "0" ]
1102                 then
1103                         case "${output_format}" in
1104                                 sys)
1105                                         ret="${ret} ${sysblock}"
1106                                         ;;
1107                                 *)
1108                                         devname=$(sys2dev "${sysblock}")
1109                                         ret="${ret} ${devname}"
1110                                         ;;
1111                         esac
1112                 fi
1113         done
1114
1115         echo "${ret}"
1116 }
1117
1118 link_files ()
1119 {
1120         # create source's directory structure in dest, and recursively
1121         # create symlinks in dest to to all files in source. if mask
1122         # is non-empty, remove mask from all source paths when
1123         # creating links (will be necessary if we change root, which
1124         # live-boot normally does (into $rootmnt)).
1125
1126         # remove multiple /:s and ensure ending on /
1127         local src_dir="$(trim_path ${1})/"
1128         local dest_dir="$(trim_path ${2})/"
1129         local src_mask="${3}"
1130
1131         # This check can only trigger on the inital, non-recursive call since
1132         # we create the destination before recursive calls
1133         if [ ! -d "${dest_dir}" ]
1134         then
1135                 log_warning_msg "Must link_files into a directory"
1136                 return
1137         fi
1138
1139         find "${src_dir}" -mindepth 1 -maxdepth 1 | \
1140         while read src
1141         do
1142                 local dest="${dest_dir}$(basename "${src}")"
1143                 if [ -d "${src}" ]
1144                 then
1145                         if [ -z "$(ls -A "${src}")" ]
1146                         then
1147                                 continue
1148                         fi
1149                         if [ ! -d "${dest}" ]
1150                         then
1151                                 mkdir -p "${dest}"
1152                                 chown_ref "${src}" "${dest}"
1153                                 chmod_ref "${src}" "${dest}"
1154                         fi
1155                         link_files "${src}" "${dest}" "${src_mask}"
1156                 else
1157                         local final_src=${src}
1158                         if [ -n "${src_mask}" ]
1159                         then
1160                                 final_src="$(echo ${final_src} | sed "s|^${src_mask}||")"
1161                         fi
1162                         rm -rf "${dest}" 2> /dev/null
1163                         ln -s "${final_src}" "${dest}"
1164                         chown_ref "${src}" "${dest}"
1165                 fi
1166         done
1167 }
1168
1169 do_union ()
1170 {
1171         local unionmountpoint="${1}"    # directory where the union is mounted
1172         local unionrw="${2}"            # branch where the union changes are stored
1173         local unionro1="${3}"           # first underlying read-only branch (optional)
1174         local unionro2="${4}"           # second underlying read-only branch (optional)
1175
1176         case "${UNIONTYPE}" in
1177                 aufs)
1178                         rw_opt="rw"
1179                         ro_opt="rr+wh"
1180                         noxino_opt="noxino"
1181                         ;;
1182
1183                 unionfs-fuse)
1184                         rw_opt="RW"
1185                         ro_opt="RO"
1186                         ;;
1187
1188                 *)
1189                         rw_opt="rw"
1190                         ro_opt="ro"
1191                         ;;
1192         esac
1193
1194         case "${UNIONTYPE}" in
1195                 unionfs-fuse)
1196                         unionmountopts="-o cow -o noinitgroups -o default_permissions -o allow_other -o use_ino -o suid"
1197                         unionmountopts="${unionmountopts} ${unionrw}=${rw_opt}"
1198                         if [ -n "${unionro1}" ]
1199                         then
1200                                 unionmountopts="${unionmountopts}:${unionro1}=${ro_opt}"
1201                         fi
1202                         if [ -n "${unionro2}" ]
1203                         then
1204                                 unionmountopts="${unionmountopts}:${unionro2}=${ro_opt}"
1205                         fi
1206                         ( sysctl -w fs.file-max=391524 ; ulimit -HSn 16384
1207                         unionfs-fuse ${unionmountopts} "${unionmountpoint}" ) && \
1208                         ( mkdir -p /run/sendsigs.omit.d
1209                         pidof unionfs-fuse >> /run/sendsigs.omit.d/unionfs-fuse || true )
1210                         ;;
1211
1212                 overlayfs)
1213                         # XXX: can unionro2 be used? (overlayfs only handles two dirs, but perhaps they can be chained?)
1214                         # XXX: and can unionro1 be optional? i.e. can overlayfs skip lowerdir?
1215                         unionmountopts="-o noatime,lowerdir=${unionro1},upperdir=${unionrw}"
1216                         mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
1217                         ;;
1218
1219                 *)
1220                         unionmountopts="-o noatime,${noxino_opt},dirs=${unionrw}=${rw_opt}"
1221                         if [ -n "${unionro1}" ]
1222                         then
1223                                 unionmountopts="${unionmountopts}:${unionro1}=${ro_opt}"
1224                         fi
1225                         if [ -n "${unionro2}" ]
1226                         then
1227                                 unionmountopts="${unionmountopts}:${unionro2}=${ro_opt}"
1228                         fi
1229                         mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
1230                         ;;
1231         esac
1232 }
1233
1234 get_custom_mounts ()
1235 {
1236         # Side-effect: leaves $devices with live-persistence.conf mounted in /live/persistence
1237         # Side-effect: prints info to file $custom_mounts
1238
1239         local custom_mounts=${1}
1240         shift
1241         local devices=${@}
1242
1243         local bindings="/tmp/bindings.list"
1244         local links="/tmp/links.list"
1245         rm -rf ${bindings} ${links} 2> /dev/null
1246
1247         for device in ${devices}
1248         do
1249                 if [ ! -b "${device}" ]
1250                 then
1251                         continue
1252                 fi
1253
1254                 local device_name="$(basename ${device})"
1255                 local backing=$(mount_persistence_media ${device})
1256                 if [ -z "${backing}" ]
1257                 then
1258                         continue
1259                 fi
1260
1261                 local include_list="${backing}/${persistence_list}"
1262                 if [ ! -r "${include_list}" ]
1263                 then
1264                         continue
1265                 fi
1266
1267                 if [ -n "${DEBUG}" ] && [ -e "${include_list}" ]
1268                 then
1269                         cp ${include_list} /live/persistence/${persistence_list}.${device_name}
1270                 fi
1271
1272                 while read dir options # < ${include_list}
1273                 do
1274                         if echo ${dir} | grep -qe "^[[:space:]]*\(#.*\)\?$"
1275                         then
1276                                 # skipping empty or commented lines
1277                                 continue
1278                         fi
1279
1280                         if trim_path ${dir} | grep -q -e "^[^/]" -e "^/live\(/.*\)\?$" -e "^/\(.*/\)\?\.\.\?\(/.*\)\?$"
1281                         then
1282                                 log_warning_msg "Skipping unsafe custom mount ${dir}: must be an absolute path containing neither the \".\" nor \"..\" special dirs, and cannot be \"/live\" or any sub-directory therein."
1283                                 continue
1284                         fi
1285
1286                         local opt_source=""
1287                         local opt_link=""
1288                         for opt in $(echo ${options} | tr ',' ' ');
1289                         do
1290                                 case "${opt}" in
1291                                         source=*)
1292                                                 opt_source=${opt#source=}
1293                                                 ;;
1294                                         link)
1295                                                 opt_link="true"
1296                                                 ;;
1297                                         union|bind)
1298                                                 ;;
1299                                         *)
1300                                                 log_warning_msg "Skipping custom mount with unkown option: ${opt}"
1301                                                 continue 2
1302                                                 ;;
1303                                 esac
1304                         done
1305
1306                         local source="${dir}"
1307                         if [ -n "${opt_source}" ]
1308                         then
1309                                 if echo ${opt_source} | grep -q -e "^/" -e "^\(.*/\)\?\.\.\?\(/.*\)\?$" && [ "${opt_source}" != "." ]
1310                                 then
1311                                         log_warning_msg "Skipping unsafe custom mount with option source=${opt_source}: must be either \".\" (the media root) or a relative path w.r.t. the media root that contains neither comas, nor the special \".\" and \"..\" path components"
1312                                         continue
1313                                 else
1314                                         source="${opt_source}"
1315                                 fi
1316                         fi
1317
1318                         local full_source="$(trim_path ${backing}/${source})"
1319                         local full_dest="$(trim_path ${rootmnt}/${dir})"
1320                         if [ -n "${opt_link}" ]
1321                         then
1322                                 echo "${device} ${full_source} ${full_dest} ${options}" >> ${links}
1323                         else
1324                                 echo "${device} ${full_source} ${full_dest} ${options}" >> ${bindings}
1325                         fi
1326                 done < ${include_list}
1327         done
1328
1329         # We sort the list according to destination so we're sure that
1330         # we won't hide a previous mount. We also ignore duplicate
1331         # destinations in a more or less arbitrary way.
1332         [ -e "${bindings}" ] && sort -k3 -sbu ${bindings} >> ${custom_mounts} && rm ${bindings}
1333
1334         # After all mounts are considered we add symlinks so they
1335         # won't be hidden by some mount.
1336         [ -e "${links}" ] && cat ${links} >> ${custom_mounts} && rm ${links}
1337
1338         # We need to make sure that no two custom mounts have the same sources
1339         # or are nested; if that is the case, too much weird stuff can happen.
1340         local prev_source="impossible source" # first iteration must not match
1341         local prev_dest=""
1342         # This sort will ensure that a source /a comes right before a source
1343         # /a/b so we only need to look at the previous source
1344         sort -k2 -b ${custom_mounts} |
1345         while read device source dest options
1346         do
1347                 if echo ${source} | grep -qe "^${prev_source}\(/.*\)\?$"
1348                 then
1349                         panic "Two persistence mounts have the same or nested sources: ${source} on ${dest}, and ${prev_source} on ${prev_dest}"
1350                 fi
1351                 prev_source=${source}
1352                 prev_dest=${dest}
1353         done
1354 }
1355
1356 activate_custom_mounts ()
1357 {
1358         local custom_mounts="${1}" # the ouput from get_custom_mounts()
1359         local used_devices=""
1360
1361         while read device source dest options # < ${custom_mounts}
1362         do
1363                 local opt_bind="true"
1364                 local opt_link=""
1365                 local opt_union=""
1366                 for opt in $(echo ${options} | tr ',' ' ');
1367                 do
1368                         case "${opt}" in
1369                                 bind)
1370                                         opt_bind="true"
1371                                         unset opt_link opt_union
1372                                         ;;
1373                                 link)
1374                                         opt_link="true"
1375                                         unset opt_bind opt_union
1376                                         ;;
1377                                 union)
1378                                         opt_union="true"
1379                                         unset opt_bind opt_link
1380                                         ;;
1381                         esac
1382                 done
1383
1384                 if [ -n "$(what_is_mounted_on "${dest}")" ]
1385                 then
1386                         if [ "${dest}" = "${rootmnt}" ]
1387                         then
1388                                 umount "${dest}"
1389                         else
1390                                 log_warning_msg "Skipping custom mount ${dest}: $(what_is_mounted_on "${dest}") is already mounted there"
1391                                 continue
1392                         fi
1393                 fi
1394
1395                 if [ ! -d "${dest}" ]
1396                 then
1397                         # create the destination and delete existing files in
1398                         # its path that are in the way
1399                         path="/"
1400                         for dir in $(echo ${dest} | sed -e 's|/\+| |g')
1401                         do
1402                                 path=$(trim_path ${path}/${dir})
1403                                 if [ -f ${path} ]
1404                                 then
1405                                         rm -f ${path}
1406                                 fi
1407                                 if [ ! -e ${path} ]
1408                                 then
1409                                         mkdir -p ${path}
1410                                         if echo ${path} | grep -qe "^${rootmnt}/*home/[^/]\+"
1411                                         then
1412                                                 # if ${dest} is in /home try fixing proper ownership by assuming that the intended user is the first, which is usually the case
1413                                                 # FIXME: this should really be handled by live-config since we don't know for sure which uid a certain user has until then
1414                                                 chown 1000:1000 ${path}
1415                                         fi
1416                                 fi
1417                         done
1418                 fi
1419
1420                 # if ${source} doesn't exist on our persistence media
1421                 # we bootstrap it with $dest from the live filesystem.
1422                 # this both makes sense and is critical if we're
1423                 # dealing with /etc or other system dir.
1424                 if [ ! -d "${source}" ]
1425                 then
1426                         if [ -n "${PERSISTENCE_READONLY}" ]
1427                         then
1428                                 continue
1429                         elif [ -n "${opt_union}" ] || [ -n "${opt_link}" ]
1430                         then
1431                                 # unions and don't need to be bootstrapped
1432                                 # link dirs can't be bootstrapped in a sensible way
1433                                 mkdir -p "${source}"
1434                                 chown_ref "${dest}" "${source}"
1435                                 chmod_ref "${dest}" "${source}"
1436                         elif [ -n "${opt_bind}" ]
1437                         then
1438                                 # ensure that $dest is not copied *into* $source
1439                                 mkdir -p "$(dirname ${source})"
1440                                 cp -a "${dest}" "${source}"
1441                         fi
1442                 fi
1443
1444                 # XXX: If CONFIG_AUFS_ROBR is added to the Debian kernel we can
1445                 # ignore the loop below and set rofs_dest_backing=$dest
1446                 local rofs_dest_backing=""
1447                 if [ -n "${opt_link}"]
1448                 then
1449                         for d in /live/rofs/*
1450                         do
1451                                 if [ -n "${rootmnt}" ]
1452                                 then
1453                                         rofs_dest_backing="${d}/$(echo ${dest} | sed -e "s|${rootmnt}||")"
1454                                 else
1455                                         rofs_dest_backing="${d}/${dest}"
1456                                 fi
1457                                 if [ -d "${rofs_dest_backing}" ]
1458                                 then
1459                                         break
1460                                 else
1461                                         rofs_dest_backing=""
1462                                 fi
1463                         done
1464                 fi
1465
1466                 if [ -n "${opt_link}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1467                 then
1468                         link_files ${source} ${dest} ${rootmnt}
1469                 elif [ -n "${opt_link}" ] && [ -n "${PERSISTENCE_READONLY}" ]
1470                 then
1471                         mkdir -p /live/persistence
1472                         local links_source=$(mktemp -d /live/persistence/links-source-XXXXXX)
1473                         chown_ref ${source} ${links_source}
1474                         chmod_ref ${source} ${links_source}
1475                         # We put the cow dir in the below strange place to
1476                         # make it absolutely certain that the link source
1477                         # has its own directory and isn't nested with some
1478                         # other custom mount (if so that mount's files would
1479                         # be linked, causing breakage.
1480                         local cow_dir="/live/overlay/live/persistence/$(basename ${links_source})"
1481                         mkdir -p ${cow_dir}
1482                         chown_ref "${source}" "${cow_dir}"
1483                         chmod_ref "${source}" "${cow_dir}"
1484                         do_union ${links_source} ${cow_dir} ${source} ${rofs_dest_backing}
1485                         link_files ${links_source} ${dest} ${rootmnt}
1486                 elif [ -n "${opt_union}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1487                 then
1488                         do_union ${dest} ${source} ${rofs_dest_backing}
1489                 elif [ -n "${opt_bind}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1490                 then
1491                         mount --bind "${source}" "${dest}"
1492                 elif [ -n "${opt_bind}" -o -n "${opt_union}" ] && [ -n "${PERSISTENCE_READONLY}" ]
1493                 then
1494                         # bind-mount and union mount are handled the same
1495                         # in read-only mode, but note that rofs_dest_backing
1496                         # is non-empty (and necessary) only for unions
1497                         if [ -n "${rootmnt}" ]
1498                         then
1499                                 local cow_dir="$(echo ${dest} | sed -e "s|^${rootmnt}|/live/overlay/|")"
1500                         else
1501                                 # This is happens if persistence is activated
1502                                 # post boot
1503                                 local cow_dir="/live/overlay/${dest}"
1504                         fi
1505                         if [ -e "${cow_dir}" ] && [ -z "${opt_link}" ]
1506                         then
1507                                 # If an earlier custom mount has files here
1508                                 # it will "block" the current mount's files
1509                                 # which is undesirable
1510                                 rm -rf "${cow_dir}"
1511                         fi
1512                         mkdir -p ${cow_dir}
1513                         chown_ref "${source}" "${cow_dir}"
1514                         chmod_ref "${source}" "${cow_dir}"
1515                         do_union ${dest} ${cow_dir} ${source} ${rofs_dest_backing}
1516                 fi
1517
1518                 PERSISTENCE_IS_ON="1"
1519                 export PERSISTENCE_IS_ON
1520
1521                 if echo ${used_devices} | grep -qve "^\(.* \)\?${device}\( .*\)\?$"
1522                 then
1523                         used_devices="${used_devices} ${device}"
1524                 fi
1525         done < ${custom_mounts}
1526
1527         echo ${used_devices}
1528 }
1529
1530 fix_backwards_compatibility ()
1531 {
1532         local device=${1}
1533         local dir=${2}
1534         local opt=${3}
1535
1536         if [ -n "${PERSISTENCE_READONLY}" ]
1537         then
1538                 return
1539         fi
1540
1541         local backing="$(mount_persistence_media ${device})"
1542         if [ -z "${backing}" ]
1543         then
1544                 return
1545         fi
1546
1547         local include_list="${backing}/${persistence_list}"
1548         if [ ! -r "${include_list}" ]
1549         then
1550                 echo "# persistence backwards compatibility:
1551 ${dir} ${opt},source=." > "${include_list}"
1552         fi
1553 }
1554
1555 is_mountpoint ()
1556 {
1557         directory="$1"
1558
1559         [ $(stat -fc%d:%D "${directory}") != $(stat -fc%d:%D "${directory}/..") ]
1560 }