scripts/live-helpers

   1 # live-boot helper functions, used by live-boot on boot and by live-snapshot
   2
   3 if [ ! -x "/bin/fstype" ]
   4 then
   5         # klibc not in path -> not in initramfs
   6         export PATH="${PATH}:/usr/lib/klibc/bin"
   7 fi
   8
   9 # handle upgrade path from old udev (using udevinfo) to
  10 # recent versions of udev (using udevadm info)
  11 if [ -x /sbin/udevadm ]
  12 then
  13         udevinfo='/sbin/udevadm info'
  14 else
  15         udevinfo='udevinfo'
  16 fi
  17
  18 root_overlay_label="full-ov"
  19 old_root_overlay_label="live-rw"
  20 old_home_overlay_label="home-rw"
  21 custom_overlay_label="custom-ov"
  22 root_snapshot_label="live-sn"
  23 old_root_snapshot_label="live-sn"
  24 home_snapshot_label="home-sn"
  25 persistence_list="live.persist"
  26
  27 Arguments ()
  28 {
  29         PRESEEDS=""
  30         LOCATIONS=""
  31
  32         for ARGUMENT in $(cat /proc/cmdline)
  33         do
  34                 case "${ARGUMENT}" in
  35                         skipconfig)
  36                                 NOACCESSIBILITY="Yes"
  37                                 NOFASTBOOT="Yes"
  38                                 NOFSTAB="Yes"
  39                                 NONETWORKING="Yes"
  40
  41                                 export NOACCESSIBILITY NOFASTBOOT NOFSTAB NONETWORKING
  42                                 ;;
  43
  44                         access=*)
  45                                 ACCESS="${ARGUMENT#access=}"
  46                                 export ACCESS
  47                                 ;;
  48
  49                         console=*)
  50                                 DEFCONSOLE="${ARGUMENT#*=}"
  51                                 export DEFCONSOLE
  52                                 ;;
  53
  54                         BOOTIF=*)
  55                                 BOOTIF="${x#BOOTIF=}"
  56                                 ;;
  57
  58                         debug)
  59                                 DEBUG="Yes"
  60                                 export DEBUG
  61
  62                                 set -x
  63                                 ;;
  64
  65                         dhcp)
  66                                 # Force dhcp even while netbooting
  67                                 # Use for debugging in case somebody works on fixing dhclient
  68                                 DHCP="Force";
  69                                 export DHCP
  70                                 ;;
  71
  72                         nodhcp)
  73                                 unset DHCP
  74                                 ;;
  75
  76                         ethdevice=*)
  77                                 DEVICE="${ARGUMENT#ethdevice=}"
  78                                 ETHDEVICE="${DEVICE}"
  79                                 export DEVICE ETHDEVICE
  80                                 ;;
  81
  82                         ethdevice-timeout=*)
  83                                 ETHDEV_TIMEOUT="${ARGUMENT#ethdevice-timeout=}"
  84                                 export ETHDEV_TIMEOUT
  85                                 ;;
  86
  87                         fetch=*)
  88                                 FETCH="${ARGUMENT#fetch=}"
  89                                 export FETCH
  90                                 ;;
  91
  92                         forcepersistentfsck)
  93                                 FORCEPERSISTENTFSCK="Yes"
  94                                 export FORCEPERSISTENTFSCK
  95                                 ;;
  96
  97                         ftpfs=*)
  98                                 FTPFS="${ARGUMENT#ftpfs=}"
  99                                 export FTPFS
 100                                 ;;
 101
 102                         httpfs=*)
 103                                 HTTPFS="${ARGUMENT#httpfs=}"
 104                                 export HTTPFS
 105                                 ;;
 106
 107                         iscsi=*)
 108                                 ISCSI="${ARGUMENT#iscsi=}"
 109                                 #ip:port - separated by ;
 110                                 ISCSI_PORTAL="${ISCSI%;*}"
 111                                 if echo "${ISCSI_PORTAL}" | grep -q , ; then
 112                                         ISCSI_SERVER="${ISCSI_PORTAL%,*}"
 113                                         ISCSI_PORT="${ISCSI_PORTAL#*,}"
 114                                 fi
 115                                 #target name
 116                                 ISCSI_TARGET="${ISCSI#*;}"
 117                                 export ISCSI ISCSI_PORTAL ISCSI_TARGET ISCSI_SERVER ISCSI_PORT
 118                                 ;;
 119
 120                         isofrom=*|fromiso=*)
 121                                 FROMISO="${ARGUMENT#*=}"
 122                                 export FROMISO
 123                                 ;;
 124
 125                         ignore_uuid)
 126                                 IGNORE_UUID="Yes"
 127                                 export IGNORE_UUID
 128                                 ;;
 129
 130                         integrity-check)
 131                                 INTEGRITY_CHECK="Yes"
 132                                 export INTEGRITY_CHECK
 133                                 ;;
 134
 135                         ip=*)
 136                                 STATICIP="${ARGUMENT#ip=}"
 137
 138                                 if [ -z "${STATICIP}" ]
 139                                 then
 140                                         STATICIP="frommedia"
 141                                 fi
 142
 143                                 export STATICIP
 144                                 ;;
 145
 146                         live-getty)
 147                                 LIVE_GETTY="1"
 148                                 export LIVE_GETTY
 149                                 ;;
 150
 151                         live-media=*|bootfrom=*)
 152                                 LIVE_MEDIA="${ARGUMENT#*=}"
 153                                 export LIVE_MEDIA
 154                                 ;;
 155
 156                         live-media-encryption=*|encryption=*)
 157                                 LIVE_MEDIA_ENCRYPTION="${ARGUMENT#*=}"
 158                                 export LIVE_MEDIA_ENCRYPTION
 159                                 ;;
 160
 161                         live-media-offset=*)
 162                                 LIVE_MEDIA_OFFSET="${ARGUMENT#live-media-offset=}"
 163                                 export LIVE_MEDIA_OFFSET
 164                                 ;;
 165
 166                         live-media-path=*)
 167                                 LIVE_MEDIA_PATH="${ARGUMENT#live-media-path=}"
 168                                 export LIVE_MEDIA_PATH
 169                                 ;;
 170
 171                         live-media-timeout=*)
 172                                 LIVE_MEDIA_TIMEOUT="${ARGUMENT#live-media-timeout=}"
 173                                 export LIVE_MEDIA_TIMEOUT
 174                                 ;;
 175
 176                         module=*)
 177                                 MODULE="${ARGUMENT#module=}"
 178                                 export MODULE
 179                                 ;;
 180
 181                         netboot=*)
 182                                 NETBOOT="${ARGUMENT#netboot=}"
 183                                 export NETBOOT
 184                                 ;;
 185
 186                         nfsopts=*)
 187                                 NFSOPTS="${ARGUMENT#nfsopts=}"
 188                                 export NFSOPTS
 189                                 ;;
 190
 191                         nfscow=*)
 192                                 NFS_COW="${ARGUMENT#nfscow=}"
 193                                 export NFS_COW
 194                                 ;;
 195
 196                         noaccessibility)
 197                                 NOACCESSIBILITY="Yes"
 198                                 export NOACCESSIBILITY
 199                                 ;;
 200
 201                         nofastboot)
 202                                 NOFASTBOOT="Yes"
 203                                 export NOFASTBOOT
 204                                 ;;
 205
 206                         nofstab)
 207                                 NOFSTAB="Yes"
 208                                 export NOFSTAB
 209                                 ;;
 210
 211                         nonetworking)
 212                                 NONETWORKING="Yes"
 213                                 export NONETWORKING
 214                                 ;;
 215
 216                         ramdisk-size=*)
 217                                 ramdisk_size="${ARGUMENT#ramdisk-size=}"
 218                                 ;;
 219
 220                         swapon)
 221                                 SWAPON="Yes"
 222                                 export SWAPON
 223                                 ;;
 224
 225                         persistent)
 226                                 PERSISTENT="Yes"
 227                                 export PERSISTENT
 228                                 ;;
 229
 230                         persistent-encryption=*)
 231                                 PERSISTENT_ENCRYPTION="${ARGUMENT#*=}"
 232                                 export PERSISTENT_ENCRYPTION
 233                                 ;;
 234
 235                         persistent-media=*)
 236                                 PERSISTENT_MEDIA="${ARGUMENT#*=}"
 237                                 export PERSISTENT_MEDIA
 238                                 ;;
 239                         persistent-method=*)
 240                                 PERSISTENT_METHOD="${ARGUMENT#*=}"
 241                                 export PERSISTENT_METHOD
 242                                 ;;
 243
 244                         persistent-path=*)
 245                                 PERSISTENT_PATH="${ARGUMENT#persistent-path=}"
 246                                 export PERSISTENT_PATH
 247                                 ;;
 248                         persistent-read-only)
 249                                 PERSISTENT_READONLY="Yes"
 250                                 export PERSISTENT_READONLY
 251                                 ;;
 252
 253                         persistent-storage=*)
 254                                 PERSISTENT_STORAGE="${ARGUMENT#persistent-storage=}"
 255                                 export PERSISTENT_STORAGE
 256                                 ;;
 257
 258                         persistent-subtext=*)
 259                                 root_overlay_label="${root_overlay_label}-${ARGUMENT#persistent-subtext=}"
 260                                 old_root_overlay_label="${old_root_overlay_label}-${ARGUMENT#persistent-subtext=}"
 261                                 old_home_overlay_label="${old_home_overlay_label}-${ARGUMENT#persistent-subtext=}"
 262                                 custom_overlay_label="${custom_overlay_label}-${ARGUMENT#persistent-subtext=}"
 263                                 root_snapshot_label="${root_snapshot_label}-${ARGUMENT#persistent-subtext=}"
 264                                 old_root_snapshot_label="${root_snapshot_label}-${ARGUMENT#persistent-subtext=}"
 265                                 home_snapshot_label="${home_snapshot_label}-${ARGUMENT#persistent-subtext=}"
 266                                 ;;
 267
 268                         nopersistent)
 269                                 NOPERSISTENT="Yes"
 270                                 export NOPERSISTENT
 271                                 ;;
 272
 273                         noprompt)
 274                                 NOPROMPT="Yes"
 275                                 export NOPROMPT
 276                                 ;;
 277
 278                         noprompt=*)
 279                                 NOPROMPT="${ARGUMENT#noprompt=}"
 280                                 export NOPROMPT
 281                                 ;;
 282
 283                         quickusbmodules)
 284                                 QUICKUSBMODULES="Yes"
 285                                 export QUICKUSBMODULES
 286                                 ;;
 287
 288                         preseed/file=*|file=*)
 289                                 LOCATIONS="${ARGUMENT#*=} ${LOCATIONS}"
 290                                 export LOCATIONS
 291                                 ;;
 292
 293                         nopreseed)
 294                                 NOPRESEED="Yes"
 295                                 export NOPRESEED
 296                                 ;;
 297
 298                         */*=*)
 299                                 question="${ARGUMENT%%=*}"
 300                                 value="${ARGUMENT#*=}"
 301                                 PRESEEDS="${PRESEEDS}\"${question}=${value}\" "
 302                                 export PRESEEDS
 303                                 ;;
 304
 305                         showmounts)
 306                                 SHOWMOUNTS="Yes"
 307                                 export SHOWMOUNTS
 308                                 ;;
 309
 310                         silent)
 311                                 SILENT="Yes"
 312                                 export SILENT
 313                                 ;;
 314
 315                         todisk=*)
 316                                 TODISK="${ARGUMENT#todisk=}"
 317                                 export TODISK
 318                                 ;;
 319
 320                         toram)
 321                                 TORAM="Yes"
 322                                 export TORAM
 323                                 ;;
 324
 325                         toram=*)
 326                                 TORAM="Yes"
 327                                 MODULETORAM="${ARGUMENT#toram=}"
 328                                 export TORAM MODULETORAM
 329                                 ;;
 330
 331                         exposedroot)
 332                                 EXPOSED_ROOT="Yes"
 333                                 export EXPOSED_ROOT
 334                                 ;;
 335
 336                         plainroot)
 337                                 PLAIN_ROOT="Yes"
 338                                 export PLAIN_ROOT
 339                                 ;;
 340
 341                         skipunion)
 342                                 SKIP_UNION_MOUNTS="Yes"
 343                                 export SKIP_UNION_MOUNTS
 344                                 ;;
 345
 346                         root=*)
 347                                 ROOT="${ARGUMENT#root=}"
 348                                 export ROOT
 349                                 ;;
 350
 351                         union=*)
 352                                 UNIONTYPE="${ARGUMENT#union=}"
 353                                 export UNIONTYPE
 354                                 ;;
 355                 esac
 356         done
 357
 358         # sort of compatibility with netboot.h from linux docs
 359         if [ -z "${NETBOOT}" ]
 360         then
 361                 if [ "${ROOT}" = "/dev/nfs" ]
 362                 then
 363                         NETBOOT="nfs"
 364                         export NETBOOT
 365                 elif [ "${ROOT}" = "/dev/cifs" ]
 366                 then
 367                         NETBOOT="cifs"
 368                         export NETBOOT
 369                 fi
 370         fi
 371
 372         if [ -z "${MODULE}" ]
 373         then
 374                 MODULE="filesystem"
 375                 export MODULE
 376         fi
 377
 378         if [ -z "${UNIONTYPE}" ]
 379         then
 380                 UNIONTYPE="aufs"
 381                 export UNIONTYPE
 382         fi
 383
 384         if [ -z "${PERSISTENT_ENCRYPTION}" ]
 385         then
 386                 PERSISTENT_ENCRYPTION="none"
 387                 export PERSISTENT_ENCRYPTION
 388         elif echo ${PERSISTENT_ENCRYPTION} | grep -qe "\<luks\>"
 389         then
 390                 if ! modprobe dm-crypt
 391                 then
 392                         log_warning_msg "Unable to load module dm-crypt"
 393                         PERSISTENT_ENCRYPTION=$(echo ${PERSISTENT_ENCRYPTION} | sed -e 's/\<luks,\|,\?luks$//g')
 394                         export PERSISTENT_ENCRYPTION
 395                 fi
 396
 397                 if [ ! -x /lib/cryptsetup/askpass ] || [ ! -x /sbin/cryptsetup ]
 398                 then
 399                         log_warning_msg "cryptsetup in unavailable"
 400                         PERSISTENT_ENCRYPTION=$(echo ${PERSISTENT_ENCRYPTION} | sed -e 's/\<luks,\|,\?luks$//g')
 401                         export PERSISTENT_ENCRYPTION
 402                 fi
 403         fi
 404
 405         if [ -z "${PERSISTENT_METHOD}" ]
 406         then
 407                 PERSISTENT_METHOD="snapshot,overlay"
 408                 export PERSISTENT_METHOD
 409         fi
 410
 411         if [ -z "${PERSISTENT_STORAGE}" ]
 412         then
 413                 PERSISTENT_STORAGE="filesystem,file"
 414                 export PERSISTENT_STORAGE
 415         fi
 416 }
 417
 418 sys2dev ()
 419 {
 420         sysdev=${1#/sys}
 421         echo "/dev/$($udevinfo -q name -p ${sysdev} 2>/dev/null|| echo ${sysdev##*/})"
 422 }
 423
 424 subdevices ()
 425 {
 426         sysblock=${1}
 427         r=""
 428
 429         for dev in "${sysblock}"/* "${sysblock}"
 430         do
 431                 if [ -e "${dev}/dev" ]
 432                 then
 433                         r="${r} ${dev}"
 434                 fi
 435         done
 436
 437         echo ${r}
 438 }
 439
 440 storage_devices()
 441 {
 442         black_listed_devices="${1}"
 443         white_listed_devices="${2}"
 444
 445         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "loop|ram|fd")
 446         do
 447                 fulldevname=$(sys2dev "${sysblock}")
 448
 449                 if echo "${black_listed_devices}" | grep -qe "\<${fulldevname}\>" || \
 450                         [ -n "${white_listed_devices}" ] && \
 451                         echo "${white_listed_devices}" | grep -qve "\<${fulldevname}\>"
 452                 then
 453                         # skip this device entirely
 454                         continue
 455                 fi
 456
 457                 for dev in $(subdevices "${sysblock}")
 458                 do
 459                         devname=$(sys2dev "${dev}")
 460
 461                         if echo "${black_listed_devices}" | grep -qe "\<${devname}\>"
 462                         then
 463                                 # skip this subdevice
 464                                 continue
 465                         else
 466                                 echo "${devname}"
 467                         fi
 468                 done
 469         done
 470 }
 471
 472 is_supported_fs ()
 473 {
 474         fstype="${1}"
 475
 476         # Validate input first
 477         if [ -z "${fstype}" ]
 478         then
 479                 return 1
 480         fi
 481
 482         # Try to look if it is already supported by the kernel
 483         if grep -q ${fstype} /proc/filesystems
 484         then
 485                 return 0
 486         else
 487                 # Then try to add support for it the gentle way using the initramfs capabilities
 488                 modprobe ${fstype}
 489                 if grep -q ${fstype} /proc/filesystems
 490                 then
 491                         return 0
 492                 # Then try the hard way if /root is already reachable
 493                 else
 494                         kmodule="/root/lib/modules/`uname -r`/${fstype}/${fstype}.ko"
 495                         if [ -e "${kmodule}" ]
 496                         then
 497                                 insmod "${kmodule}"
 498                                 if grep -q ${fstype} /proc/filesystems
 499                                 then
 500                                         return 0
 501                                 fi
 502                         fi
 503                 fi
 504         fi
 505
 506         return 1
 507 }
 508
 509 get_fstype ()
 510 {
 511         /sbin/blkid -s TYPE -o value $1 2>/dev/null
 512 }
 513
 514 where_is_mounted ()
 515 {
 516         device=${1}
 517         # return first found
 518         grep -m1 "^${device} " /proc/mounts | cut -f2 -d ' '
 519 }
 520
 521 trim_path () {
 522     # remove all unnecessary /:s in the path, including last one (except
 523     # if path is just "/")
 524     echo ${1} | sed 's|//\+|/|g' | sed 's|^\(.*[^/]\)/$|\1|'
 525 }
 526
 527 what_is_mounted_on ()
 528 {
 529         local dir="$(trim_path ${1})"
 530         grep -m1 "^[^ ]\+ ${dir} " /proc/mounts | cut -d' ' -f1
 531 }
 532
 533 lastline ()
 534 {
 535         while read lines
 536         do
 537                 line=${lines}
 538         done
 539
 540         echo "${line}"
 541 }
 542
 543 base_path ()
 544 {
 545         testpath="${1}"
 546         mounts="$(awk '{print $2}' /proc/mounts)"
 547         testpath="$(busybox realpath ${testpath})"
 548
 549         while true
 550         do
 551                 if echo "${mounts}" | grep -qs "^${testpath}"
 552                 then
 553                         set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
 554                         echo ${1}
 555                         break
 556                 else
 557                         testpath=$(dirname $testpath)
 558                 fi
 559         done
 560 }
 561
 562 fs_size ()
 563 {
 564         # Returns used/free fs kbytes + 5% more
 565         # You could pass a block device as ${1} or the mount point as ${2}
 566
 567         dev="${1}"
 568         mountp="${2}"
 569         used="${3}"
 570
 571         if [ -z "${mountp}" ]
 572         then
 573                 mountp="$(where_is_mounted ${dev})"
 574
 575                 if [ -z "${mountp}" ]
 576                 then
 577                         mountp="/mnt/tmp_fs_size"
 578
 579                         mkdir -p "${mountp}"
 580                         mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}" || log_warning_msg "cannot mount -t $(get_fstype ${dev}) -o ro ${dev} ${mountp}"
 581
 582                         doumount=1
 583                 fi
 584         fi
 585
 586         if [ "${used}" = "used" ]
 587         then
 588                 size=$(du -ks ${mountp} | cut -f1)
 589                 size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
 590         else
 591                 # free space
 592                 size="$(df -k | grep -s ${mountp} | awk '{print $4}')"
 593         fi
 594
 595         if [ -n "${doumount}" ]
 596         then
 597                 umount "${mountp}" || log_warning_msg "cannot umount ${mountp}"
 598                 rmdir "${mountp}"
 599         fi
 600
 601         echo "${size}"
 602 }
 603
 604 load_keymap ()
 605 {
 606         # Load custom keymap
 607         if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
 608         then
 609                 loadkeys /etc/boottime.kmap.gz
 610         fi
 611 }
 612
 613 setup_loop ()
 614 {
 615         local fspath=${1}
 616         local module=${2}
 617         local pattern=${3}
 618         local offset=${4}
 619         local encryption=${5}
 620         local readonly=${6}
 621
 622         # the output of setup_loop is evaluated in other functions,
 623         # modprobe leaks kernel options like "libata.dma=0"
 624         # as "options libata dma=0" on stdout, causing serious
 625         # problems therefor, so instead always avoid output to stdout
 626         modprobe -q -b "${module}" 1>/dev/null
 627
 628         udevadm settle
 629
 630         for loopdev in ${pattern}
 631         do
 632                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 633                 then
 634                         dev=$(sys2dev "${loopdev}")
 635                         options=''
 636
 637                         if [ -n "${readonly}" ]
 638                         then
 639                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 640                                 then
 641                                         options="${options} -r"
 642                                 fi
 643                         fi
 644
 645                         if [ -n "${offset}" ] && [ 0 -lt "${offset}" ]
 646                         then
 647                                 options="${options} -o ${offset}"
 648                         fi
 649
 650                         if [ -z "${encryption}" ]
 651                         then
 652                                 losetup ${options} "${dev}" "${fspath}"
 653                         else
 654                                 # Loop AES encryption
 655                                 while true
 656                                 do
 657                                         load_keymap
 658
 659                                         echo -n "Enter passphrase for root filesystem: " >&6
 660                                         read -s passphrase
 661                                         echo "${passphrase}" > /tmp/passphrase
 662                                         unset passphrase
 663                                         exec 9</tmp/passphrase
 664                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 665                                         error=${?}
 666                                         exec 9<&-
 667                                         rm -f /tmp/passphrase
 668
 669                                         if [ 0 -eq ${error} ]
 670                                         then
 671                                                 unset error
 672                                                 break
 673                                         fi
 674
 675                                         echo
 676                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 677                                         read answer
 678
 679                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 680                                         then
 681                                                 unset answer
 682                                                 break
 683                                         fi
 684                                 done
 685                         fi
 686
 687                         echo "${dev}"
 688                         return 0
 689                 fi
 690         done
 691
 692         panic "No loop devices available"
 693 }
 694
 695 try_mount ()
 696 {
 697         dev="${1}"
 698         mountp="${2}"
 699         opts="${3}"
 700         fstype="${4}"
 701
 702         old_mountp="$(where_is_mounted ${dev})"
 703
 704         if [ -n "${old_mountp}" ]
 705         then
 706                 if [ "${opts}" != "ro" ]
 707                 then
 708                         mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
 709                 fi
 710
 711                 mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
 712         else
 713                 if [ -z "${fstype}" ]
 714                 then
 715                         fstype=$(get_fstype "${dev}")
 716                 fi
 717                 mount -t "${fstype}" -o "${opts}" "${dev}" "${mountp}" || \
 718                 ( echo "SKIPPING: Cannot mount ${dev} on ${mountp}, fstype=${fstype}, options=${opts}" > live-boot.log && return 0 )
 719         fi
 720 }
 721
 722 mount_persistent_media ()
 723 {
 724         local device=${1}
 725         local backing=""
 726
 727         # We can't mount into ${rootmnt}/live before ${rootmnt} has been
 728         # mounted since that would cover our mountpoint.
 729         if [ -n "${rootmnt}" ] && [ -z "$(what_is_mounted_on ${rootmnt})" ]
 730         then
 731                 backing="/$(basename ${device})-backing"
 732         else
 733                 backing="${rootmnt}/live/persistent/$(basename ${device})"
 734         fi
 735
 736         mkdir -p "${backing}"
 737         local old_backing="$(where_is_mounted ${device})"
 738         if [ -z "${old_backing}" ]
 739         then
 740                 local fstype="$(get_fstype ${device})"
 741                 local mount_opts="rw,noatime"
 742                 if [ -n "${PERSISTENT_READONLY}" ]
 743                 then
 744                         mount_opts="ro,noatime"
 745                 fi
 746                 if mount -t "${fstype}" -o "${mount_opts}" "${device}" "${backing}" >/dev/null
 747                 then
 748                         echo ${backing}
 749                         return 0
 750                 else
 751                         log_warning_msg "Failed to mount persistent media ${device}"
 752                         return 1
 753                 fi
 754         elif [ "${backing}" != "${old_backing}" ]
 755         then
 756                 if mount --move ${old_backing} ${backing} >/dev/null
 757                 then
 758                         echo ${backing}
 759                         return 0
 760                 else
 761                         log_warning_msg "Failed to move persistent media ${device}"
 762                         return 1
 763                 fi
 764         fi
 765         return 0
 766 }
 767
 768 close_persistent_media () {
 769         local device=${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 ${dev})"
 788         opts="--key-file=-"
 789         if [ -n "${PERSISTENT_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 snapshots="${2}"
 850         local dev="${3}"
 851
 852         local gpt_dev="${dev}"
 853         if is_active_luks_mapping ${dev}
 854         then
 855                 # if $dev is an opened luks device, we need to check
 856                 # GPT stuff on the backing device
 857                 gpt_dev=$(get_luks_backing_device "${dev}")
 858         fi
 859
 860         if ! is_gpt_device ${gpt_dev}
 861         then
 862                 return
 863         fi
 864
 865         local gpt_name=$(get_gpt_name ${gpt_dev})
 866         for label in ${overlays} ${snapshots}
 867         do
 868                 if [ "${gpt_name}" = "${label}" ]
 869                 then
 870                         echo "${label}=${dev}"
 871                 fi
 872         done
 873 }
 874
 875 probe_for_fs_label ()
 876 {
 877         local overlays="${1}"
 878         local snapshots="${2}"
 879         local dev="${3}"
 880
 881         for label in ${overlays} ${snapshots}
 882         do
 883                 if [ "$(/sbin/blkid -s LABEL -o value $dev 2>/dev/null)" = "${label}" ]
 884                 then
 885                         echo "${label}=${dev}"
 886                 fi
 887         done
 888 }
 889
 890 probe_for_file_name ()
 891 {
 892         local overlays="${1}"
 893         local snapshots="${2}"
 894         local dev="${3}"
 895
 896         local ret=""
 897         local backing="$(mount_persistent_media ${dev})"
 898         if [ -z "${backing}" ]
 899         then
 900             return
 901         fi
 902
 903         for label in ${overlays}
 904         do
 905                 path=${backing}/${PERSISTENT_PATH}${label}
 906                 if [ -f "${path}" ]
 907                 then
 908                         local loopdev=$(setup_loop "${path}" "loop" "/sys/block/loop*")
 909                         ret="${ret} ${label}=${loopdev}"
 910                 fi
 911         done
 912         for label in ${snapshots}
 913         do
 914                 for ext in squashfs cpio.gz ext2 ext3 ext4 jffs2
 915                 do
 916                         path="${PERSISTENT_PATH}${label}.${ext}"
 917                         if [ -f "${backing}/${path}" ]
 918                         then
 919                                 ret="${ret} ${label}=${dev}:${backing}:${path}"
 920                         fi
 921                 done
 922         done
 923
 924         if [ -n "${ret}" ]
 925         then
 926                 echo ${ret}
 927         else
 928                 umount ${backing} > /dev/null 2>&1 || true
 929         fi
 930 }
 931
 932 find_persistent_media ()
 933 {
 934         # Scans devices for overlays and snapshots, and returns a whitespace
 935         # separated list of how to use them. Only overlays with a partition
 936         # label or file name in ${overlays} are returned, and ditto for
 937         # snapshots with labels in ${snapshots}.
 938         #
 939         # When scanning a LUKS device, the user will be asked to enter the
 940         # passphrase; on failure to enter it, or if no persistent partitions
 941         # or files were found, the LUKS device is closed.
 942         #
 943         # For a snapshot file the return value is ${label}=${snapdata}", where
 944         # ${snapdata} is the parameter used for try_snap().
 945         #
 946         # For all other cases (overlay/snapshot partition and overlay file) the
 947         # return value is "${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         # ${white_list_devices} is non-empty, only devices in it will be
 953         # scanned.
 954
 955         local overlays="${1}"
 956         local snapshots="${2}"
 957         local white_listed_devices="${3}"
 958         local ret=""
 959
 960         for dev in $(storage_devices "" "${white_listed_devices}")
 961         do
 962                 local result=""
 963
 964                 local luks_device=""
 965                 # Check if it's a luks device; we'll have to open the device
 966                 # in order to probe any filesystem it contains, like we do
 967                 # below. activate_custom_mounts() also depends on that any luks
 968                 # device already has been opened.
 969                 if echo ${PERSISTENT_ENCRYPTION} | grep -qe "\<luks\>" && \
 970                    is_luks_partition ${dev}
 971                 then
 972                         if luks_device=$(open_luks_device "${dev}")
 973                         then
 974                                 dev="${luks_device}"
 975                         else
 976                                 # skip $dev since we failed/chose not to open it
 977                                 continue
 978                         fi
 979                 elif echo ${PERSISTENT_ENCRYPTION} | grep -qve "\<none\>"
 980                 then
 981                         # skip $dev since we don't allow unencrypted storage
 982                         continue
 983                 fi
 984
 985                 # Probe for matching GPT partition names or filesystem labels
 986                 if echo ${PERSISTENT_STORAGE} | grep -qe "\<filesystem\>"
 987                 then
 988                         result=$(probe_for_gpt_name "${overlays}" "${snapshots}" ${dev})
 989                         if [ -n "${result}" ]
 990                         then
 991                                 ret="${ret} ${result}"
 992                                 continue
 993                         fi
 994
 995                         result=$(probe_for_fs_label "${overlays}" "${snapshots}" ${dev})
 996                         if [ -n "${result}" ]
 997                         then
 998                                 ret="${ret} ${result}"
 999                                 continue
1000                         fi
1001                 fi
1002
1003                 # Probe for files with matching name on mounted partition
1004                 if echo ${PERSISTENT_STORAGE} | grep -qe "\<file\>"
1005                 then
1006                         result=$(probe_for_file_name "${overlays}" "${snapshots}" ${dev})
1007                         if [ -n "${result}" ]
1008                         then
1009                                 ret="${ret} ${result}"
1010                                 continue
1011                         fi
1012                 fi
1013
1014                 # Close luks device if it isn't used
1015                 if [ -z "${result}" ] && [ -n "${luks_device}" ] && \
1016                    is_active_luks_mapping "${luks_device}"
1017                 then
1018                         /sbin/cryptsetup luksClose "${luks_device}"
1019                 fi
1020         done
1021
1022         if [ -n "${ret}" ]
1023         then
1024                 echo ${ret}
1025         fi
1026 }
1027
1028 get_mac ()
1029 {
1030         mac=""
1031
1032         for adaptor in /sys/class/net/*
1033         do
1034                 status="$(cat ${adaptor}/iflink)"
1035
1036                 if [ "${status}" -eq 2 ]
1037                 then
1038                         mac="$(cat ${adaptor}/address)"
1039                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
1040                 fi
1041         done
1042
1043         echo ${mac}
1044 }
1045
1046 is_luks_partition ()
1047 {
1048         device="${1}"
1049         /sbin/cryptsetup isLuks "${device}" 1>/dev/null 2>&1
1050 }
1051
1052 is_active_luks_mapping ()
1053 {
1054         device="${1}"
1055         /sbin/cryptsetup status "${device}" 1>/dev/null 2>&1
1056 }
1057
1058 get_luks_backing_device () {
1059         device=${1}
1060         cryptsetup status ${device} 2> /dev/null | \
1061                 awk '{if ($1 == "device:") print $2}'
1062 }
1063
1064 removable_dev ()
1065 {
1066         output_format="${1}"
1067         want_usb="${2}"
1068         ret=
1069
1070         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
1071         do
1072                 dev_ok=
1073                 if [ "$(cat ${sysblock}/removable)" = "1" ]
1074                 then
1075                         if [ -z "${want_usb}" ]
1076                         then
1077                                 dev_ok="yes"
1078                         else
1079                                 if readlink ${sysblock} | grep -q usb
1080                                 then
1081                                         dev_ok="yes"
1082                                 fi
1083                         fi
1084                 fi
1085
1086                 if [ "${dev_ok}" = "yes" ]
1087                 then
1088                         case "${output_format}" in
1089                                 sys)
1090                                         ret="${ret} ${sysblock}"
1091                                         ;;
1092                                 *)
1093                                         devname=$(sys2dev "${sysblock}")
1094                                         ret="${ret} ${devname}"
1095                                         ;;
1096                         esac
1097                 fi
1098         done
1099
1100         echo "${ret}"
1101 }
1102
1103 removable_usb_dev ()
1104 {
1105         output_format="${1}"
1106
1107         removable_dev "${output_format}" "want_usb"
1108 }
1109
1110 non_removable_dev ()
1111 {
1112         output_format="${1}"
1113         ret=
1114
1115         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
1116         do
1117                 if [ "$(cat ${sysblock}/removable)" = "0" ]
1118                 then
1119                         case "${output_format}" in
1120                                 sys)
1121                                         ret="${ret} ${sysblock}"
1122                                         ;;
1123                                 *)
1124                                         devname=$(sys2dev "${sysblock}")
1125                                         ret="${ret} ${devname}"
1126                                         ;;
1127                         esac
1128                 fi
1129         done
1130
1131         echo "${ret}"
1132 }
1133
1134 link_files ()
1135 {
1136         # create source's directory structure in dest, and recursively
1137         # create symlinks in dest to to all files in source. if mask
1138         # is non-empty, remove mask from all source paths when
1139         # creating links (will be necessary if we change root, which
1140         # live-boot normally does (into $rootmnt)).
1141
1142         # remove multiple /:s and ensure ending on /
1143         local src_dir="$(echo "${1}"/ | sed -e 's|/\+|/|g')"
1144         local dest_dir="$(echo "${2}"/ | sed -e 's|/\+|/|g')"
1145         local src_mask="${3}"
1146
1147         # This check can only trigger on the inital, non-recursive call since
1148         # we create the destination before recursive calls
1149         if [ ! -d "${dest_dir}" ]
1150         then
1151                 log_warning_msg "Must link_files into a directory"
1152                 return
1153         fi
1154
1155         find "${src_dir}" -mindepth 1 -maxdepth 1 | while read src; do
1156                 local dest="${dest_dir}$(basename "${src}")"
1157                 if [ -d "${src}" ]
1158                 then
1159                         if [ -z "$(ls -A "${src}")" ]
1160                         then
1161                                 continue
1162                         fi
1163                         if [ ! -d "${dest}" ]
1164                         then
1165                                 mkdir -p "${dest}"
1166                                 prev="$(dirname "${dest}")"
1167                                 chown --reference "${prev}" "${dest}"
1168                                 chmod --reference "${prev}" "${dest}"
1169                         fi
1170                         link_files "${src}" "${dest}" "${src_mask}"
1171                 else
1172                         if [ -n "${src_mask}" ]
1173                         then
1174                                 src="$(echo ${src} | sed "s|^${src_mask}||")"
1175                         fi
1176                         rm -rf "${dest}" 2> /dev/null
1177                         ln -s "${src}" "${dest}"
1178                 fi
1179         done
1180 }
1181
1182 do_union ()
1183 {
1184         local unionmountpoint="${1}"    # directory where the union is mounted
1185         local unionrw="${2}"            # branch where the union changes are stored
1186         local unionro1="${3}"           # first underlying read-only branch (optional)
1187         local unionro2="${4}"           # second underlying read-only branch (optional)
1188
1189         if [ "${UNIONTYPE}" = "aufs" ]
1190         then
1191                 rw_opt="rw"
1192                 ro_opt="rr+wh"
1193                 noxino_opt="noxino"
1194         elif [ "${UNIONTYPE}" = "unionfs-fuse" ]
1195         then
1196                 rw_opt="RW"
1197                 ro_opt="RO"
1198         else
1199                 rw_opt="rw"
1200                 ro_opt="ro"
1201         fi
1202
1203         case "${UNIONTYPE}" in
1204                 unionfs-fuse)
1205                         unionmountopts="-o cow -o noinitgroups -o default_permissions -o allow_other -o use_ino -o suid"
1206                         unionmountopts="${unionmountopts} ${unionrw}=${rw_opt}"
1207                         if [ -n "${unionro1}" ]
1208                         then
1209                                 unionmountopts="${unionmountopts}:${unionro1}=${ro_opt}"
1210                         fi
1211                         if [ -n "${unionro2}" ]
1212                         then
1213                                 unionmountopts="${unionmountopts}:${unionro2}=${ro_opt}"
1214                         fi
1215                         ( sysctl -w fs.file-max=391524 ; ulimit -HSn 16384
1216                         unionfs-fuse ${unionmountopts} "${unionmountpoint}" ) && \
1217                         ( mkdir -p /run/sendsigs.omit.d
1218                         pidof unionfs-fuse >> /run/sendsigs.omit.d/unionfs-fuse || true )
1219                         ;;
1220
1221                 overlayfs)
1222                         # XXX: can unionro2 be used? (overlayfs only handles two dirs, but perhaps they can be chained?)
1223                         # XXX: and can unionro1 be optional? i.e. can overlayfs skip lowerdir?
1224                         unionmountopts="-o noatime,lowerdir=${unionro1},upperdir=${unionrw}"
1225                         mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
1226                         ;;
1227
1228                 *)
1229                         unionmountopts="-o noatime,${noxino_opt},dirs=${unionrw}=${rw_opt}"
1230                         if [ -n "${unionro1}" ]
1231                         then
1232                                 unionmountopts="${unionmountopts}:${unionro1}=${ro_opt}"
1233                         fi
1234                         if [ -n "${unionro2}" ]
1235                         then
1236                                 unionmountopts="${unionmountopts}:${unionro2}=${ro_opt}"
1237                         fi
1238                         mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
1239                         ;;
1240         esac
1241 }
1242
1243 get_custom_mounts ()
1244 {
1245         # Side-effect: leaves $devices with live.persist mounted in ${rootmnt}/live/persistent
1246         # Side-effect: prints info to file $custom_mounts
1247
1248         local custom_mounts=${1}
1249         shift
1250         local devices=${@}
1251
1252         local bindings="/tmp/bindings.list"
1253         local links="/tmp/links.list"
1254         rm -rf ${bindings} ${links} 2> /dev/null
1255
1256         for device in ${devices}
1257         do
1258                 if [ ! -b "${device}" ]
1259                 then
1260                         continue
1261                 fi
1262
1263                 local device_name="$(basename ${device})"
1264                 local backing=$(mount_persistent_media ${device})
1265                 if [ -z "${backing}" ]
1266                 then
1267                         continue
1268                 fi
1269
1270                 local include_list="${backing}/${persistence_list}"
1271                 if [ ! -r "${include_list}" ]
1272                 then
1273                         continue
1274                 fi
1275
1276                 if [ -n "${DEBUG}" ] && [ -e "${include_list}" ]
1277                 then
1278                         cp ${include_list} ${rootmnt}/live/persistent/${persistence_list}.${device_name}
1279                 fi
1280
1281                 while read dir options # < ${include_list}
1282                 do
1283                         if echo ${dir} | grep -qe "^[[:space:]]*\(#.*\)\?$"
1284                         then
1285                                 # skipping empty or commented lines
1286                                 continue
1287                         fi
1288
1289                         if trim_path ${dir} | grep -q -e "^[^/]" -e "^/$" -e "^/live\(/.*\)\?$" -e "^/\(.*/\)\?\.\.\?\(/.*\)\?$"
1290                         then
1291                                 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) or \"/\" (for the latter, use ${root_overlay_label}-type persistence)"
1292                                 continue
1293                         fi
1294
1295                         local opt_source=""
1296                         local opt_linkfiles=""
1297                         for opt in $(echo ${options} | tr ',' ' ');
1298                         do
1299                                 case "${opt}" in
1300                                         source=*)
1301                                                 opt_source=${opt#source=}
1302                                                 ;;
1303                                         linkfiles)
1304                                                 opt_linkfiles="yes"
1305                                                 ;;
1306                                         union)
1307                                                 ;;
1308                                         *)
1309                                                 log_warning_msg "Skipping custom mount with unkown option: ${opt}"
1310                                                 continue 2
1311                                                 ;;
1312                                 esac
1313                         done
1314
1315                         local source="${dir}"
1316                         if [ -n "${opt_source}" ]
1317                         then
1318                                 if echo ${opt_source} | grep -q -e "^/" -e "^\(.*/\)\?\.\.\?\(/.*\)\?$" && [ "${source}" != "." ]
1319                                 then
1320                                         log_warning_msg "Skipping unsafe custom mount with option source=${opt_source}: must be either \".\" (the media root) a relative path w.r.t. the media root that doesn't contain comas or the special dirs \".\" and \"..\""
1321                                         continue
1322                                 else
1323                                         source="${opt_source}"
1324                                 fi
1325                         fi
1326
1327                         local full_source="$(trim_path ${backing}/${source})"
1328                         local full_dest="$(trim_path ${rootmnt}/${dir})"
1329                         if [ -n "${opt_linkfiles}" ]
1330                         then
1331                                 echo "${device} ${full_source} ${full_dest} ${options}" >> ${links}
1332                         else
1333                                 echo "${device} ${full_source} ${full_dest} ${options}" >> ${bindings}
1334                         fi
1335                 done < ${include_list}
1336         done
1337
1338         # We sort the list according to destination so we're sure that
1339         # we won't hide a previous mount. We also ignore duplicate
1340         # destinations in a more or less arbitrary way.
1341         [ -e "${bindings}" ] && sort -k3 -sbu ${bindings} >> ${custom_mounts} && rm ${bindings}
1342
1343         # After all mounts are considered we add symlinks so they
1344         # won't be hidden by some mount.
1345         [ -e "${links}" ] && sort -k3 -sbu ${links} >> ${custom_mounts} && rm ${links}
1346 }
1347
1348 activate_custom_mounts ()
1349 {
1350         local custom_mounts="${1}" # the ouput from get_custom_mounts()
1351         local used_devices=""
1352
1353         while read device source dest options # < ${custom_mounts}
1354         do
1355                 local opt_linkfiles=""
1356                 local opt_union=""
1357                 for opt in $(echo ${options} | tr ',' ' ');
1358                 do
1359                          case "${opt}" in
1360                                 linkfiles)
1361                                         opt_linkfiles="yes"
1362                                         ;;
1363                                 union)
1364                                         opt_union="yes"
1365                                         ;;
1366                         esac
1367                 done
1368
1369                 if [ -n "${opt_linkfiles}" ] && [ -n "${opt_union}" ]
1370                 then
1371                         log_warning_msg "Skipping custom mount ${dest} with options ${options}: \"linkfiles\" and \"union\" are mutually exclusive options"
1372                 fi
1373
1374                 if [ -n "$(what_is_mounted_on "${dest}")" ]
1375                 then
1376                         log_warning_msg "Skipping custom mount ${dest}: $(what_is_mounted_on "${dest}") is already mounted there"
1377                         continue
1378                 fi
1379
1380                 # FIXME: we don't handle already existing
1381                 # non-directory files in the paths of both $source and
1382                 # $dest.
1383
1384                 if [ ! -d "${dest}" ]
1385                 then
1386                         # if ${dest} is in /home/$user, try fixing
1387                         # proper ownership
1388                         # FIXME: this should really be handled by
1389                         # live-config since we don't know for sure
1390                         # which uid a certain user has until then
1391                         if trim_path ${dest} | grep -qe "^${rootmnt}/*home/[^/]\+"
1392                         then
1393                                 path="/"
1394                                 for dir in $(echo ${dest} | sed -e 's|/\+| |g')
1395                                 do
1396                                         path=${path}/${dir}
1397                                         if [ ! -e ${path} ]
1398                                         then
1399                                                 mkdir -p ${path}
1400                                                 # assume that the intended user is the first, which is usually the case
1401                                                 chown 1000:1000 ${path}
1402                                         fi
1403                                 done
1404                         else
1405                                 mkdir -p ${dest}
1406                         fi
1407                 fi
1408
1409                 # if ${source} doesn't exist on our persistent media
1410                 # we bootstrap it with $dest from the live filesystem.
1411                 # this both makes sense and is critical if we're
1412                 # dealing with /etc or other system dir.
1413                 if [ ! -d "${source}" ]
1414                 then
1415                         if [ -n "${PERSISTENT_READONLY}" ]
1416                         then
1417                                 continue
1418                         elif [ -n "${opt_union}" ] || [ -n "${opt_linkfiles}" ]
1419                         then
1420                                 # unions and don't need to be bootstrapped
1421                                 # linkfiles dirs can't be bootstrapped in a sensible way
1422                                 mkdir "${source}"
1423                                 chown --reference "${dest}" "${source}"
1424                                 chmod --reference "${dest}" "${source}"
1425                         else
1426                                 # ensure that $dest is not copied *into* $source
1427                                 mkdir -p "$(dirname ${source})"
1428                                 cp -a "${dest}" "${source}"
1429                         fi
1430                 fi
1431
1432                 # XXX: If CONFIG_AUFS_ROBR is added to the Debian kernel we can
1433                 # ignore the loop below and set rofs_dest_backing=$dest
1434                 rofs_dest_backing=""
1435                 for d in ${rootmnt}/live/rofs/*
1436                 do
1437                         if [ -n "${rootmnt}" ]
1438                         then
1439                                 rofs_dest_backing="${d}/$(echo ${dest} | sed -e "s|${rootmnt}||")"
1440                         else
1441                                 rofs_dest_backing="${d}/${dest}"
1442                         fi
1443                         if [ -d "${rofs_dest_backing}" ]
1444                         then
1445                                 break
1446                         else
1447                                 rofs_dest_backing=""
1448                         fi
1449                 done
1450
1451                 if [ -z "${PERSISTENT_READONLY}" ]
1452                 then
1453                         if [ -n "${opt_linkfiles}" ]
1454                         then
1455                                 links_source="${source}"
1456                                 links_dest="${dest}"
1457                         elif [ -n "${opt_union}" ]
1458                         then
1459                                 do_union ${dest} ${source} ${rofs_dest_backing}
1460                         else
1461                                 mount --bind "${source}" "${dest}"
1462                         fi
1463                 else
1464                         if [ -n "${opt_linkfiles}" ]
1465                         then
1466                                 links_dest="${dest}"
1467                                 dest="$(mktemp -d ${persistent_backing}/links_source-XXXXXX)"
1468                                 links_source="${dest}"
1469                         fi
1470                         if [ -n "${rootmnt}" ]
1471                         then
1472                                 cow_dir="$(echo ${dest} | sed -e "s|${rootmnt}|/cow/|")"
1473                         else
1474                                 cow_dir="/live/cow/${dest}"
1475                         fi
1476                         mkdir -p ${cow_dir}
1477                         chown --reference "${source}" "${cow_dir}"
1478                         chmod --reference "${source}" "${cow_dir}"
1479                         do_union ${dest} ${cow_dir} ${source} ${rofs_dest_backing}
1480                 fi
1481
1482                 if [ -n "${opt_linkfiles}" ]
1483                 then
1484                         link_files "${links_source}" "${links_dest}" "${rootmnt}"
1485                 fi
1486
1487                 PERSISTENCE_IS_ON="1"
1488                 export PERSISTENCE_IS_ON
1489
1490                 if echo ${used_devices} | grep -qve "^\(.* \)\?${device}\( .*\)\?$"
1491                 then
1492                         used_devices="${used_devices} ${device}"
1493                 fi
1494         done < ${custom_mounts}
1495
1496         echo ${used_devices}
1497 }
1498
1499 fix_home_rw_compatibility ()
1500 {
1501         local device=${1}
1502
1503         if [ -n "${PERSISTENT_READONLY}" ]
1504         then
1505                 return
1506         fi
1507
1508         local backing="$(mount_persistent_media ${device})"
1509         if [ -z "${backing}" ]
1510         then
1511                 return
1512         fi
1513
1514         local include_list="${backing}/${persistence_list}"
1515         if [ ! -r "${include_list}" ]
1516         then
1517                 echo "# home-rw backwards compatibility:
1518 /home source=." > "${include_list}"
1519         fi
1520 }