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="${PATH}:/usr/lib/klibc/bin"
   7 fi
   8
   9 # handle upgrade path from old udev (using udevinfo) to
  10 # recent versions of udev (using udevadm info)
  11 if [ -x /sbin/udevadm ]
  12 then
  13         udevinfo='/sbin/udevadm info'
  14 else
  15         udevinfo='udevinfo'
  16 fi
  17
  18 sys2dev ()
  19 {
  20         sysdev=${1#/sys}
  21         echo "/dev/$($udevinfo -q name -p ${sysdev} 2>/dev/null|| echo ${sysdev##*/})"
  22 }
  23
  24 subdevices ()
  25 {
  26         sysblock=${1}
  27         r=""
  28
  29         for dev in "${sysblock}"/* "${sysblock}"
  30         do
  31                 if [ -e "${dev}/dev" ]
  32                 then
  33                         r="${r} ${dev}"
  34                 fi
  35         done
  36
  37         echo ${r}
  38 }
  39
  40 storage_devices()
  41 {
  42         black_listed_devices="${1}"
  43         white_listed_devices="${2}"
  44
  45         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "loop|ram|fd")
  46         do
  47                 fulldevname=$(sys2dev "${sysblock}")
  48
  49                 if echo "${black_listed_devices}" | grep -qe "\<${fulldevname}\>" || \
  50                         [ -n "${white_listed_devices}" ] && \
  51                         echo "${white_listed_devices}" | grep -qve "\<${fulldevname}\>"
  52                 then
  53                         # skip this device entirely
  54                         continue
  55                 fi
  56
  57                 for dev in $(subdevices "${sysblock}")
  58                 do
  59                         devname=$(sys2dev "${dev}")
  60
  61                         if echo "${black_listed_devices}" | grep -qe "\<${devname}\>"
  62                         then
  63                                 # skip this subdevice
  64                                 continue
  65                         else
  66                                 echo "${devname}"
  67                         fi
  68                 done
  69         done
  70 }
  71
  72 is_supported_fs ()
  73 {
  74         fstype="${1}"
  75
  76         # Validate input first
  77         if [ -z "${fstype}" ]
  78         then
  79                 return 1
  80         fi
  81
  82         # Try to look if it is already supported by the kernel
  83         if grep -q ${fstype} /proc/filesystems
  84         then
  85                 return 0
  86         else
  87                 # Then try to add support for it the gentle way using the initramfs capabilities
  88                 modprobe ${fstype}
  89                 if grep -q ${fstype} /proc/filesystems
  90                 then
  91                         return 0
  92                 # Then try the hard way if /root is already reachable
  93                 else
  94                         kmodule="/root/lib/modules/`uname -r`/${fstype}/${fstype}.ko"
  95                         if [ -e "${kmodule}" ]
  96                         then
  97                                 insmod "${kmodule}"
  98                                 if grep -q ${fstype} /proc/filesystems
  99                                 then
 100                                         return 0
 101                                 fi
 102                         fi
 103                 fi
 104         fi
 105
 106         return 1
 107 }
 108
 109 get_fstype ()
 110 {
 111         /sbin/blkid -s TYPE -o value $1 2>/dev/null
 112 }
 113
 114 where_is_mounted ()
 115 {
 116         device=${1}
 117
 118         if grep -q "^${device} " /proc/mounts
 119         then
 120                 # return the first found
 121                 grep -m1 "^${device} " /proc/mounts | cut -f2 -d ' '
 122         fi
 123 }
 124
 125 lastline ()
 126 {
 127         while read lines
 128         do
 129                 line=${lines}
 130         done
 131
 132         echo "${line}"
 133 }
 134
 135 base_path ()
 136 {
 137         testpath="${1}"
 138         mounts="$(awk '{print $2}' /proc/mounts)"
 139         testpath="$(busybox realpath ${testpath})"
 140
 141         while true
 142         do
 143                 if echo "${mounts}" | grep -qs "^${testpath}"
 144                 then
 145                         set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
 146                         echo ${1}
 147                         break
 148                 else
 149                         testpath=$(dirname $testpath)
 150                 fi
 151         done
 152 }
 153
 154 fs_size ()
 155 {
 156         # Returns used/free fs kbytes + 5% more
 157         # You could pass a block device as ${1} or the mount point as ${2}
 158
 159         dev="${1}"
 160         mountp="${2}"
 161         used="${3}"
 162
 163         if [ -z "${mountp}" ]
 164         then
 165                 mountp="$(where_is_mounted ${dev})"
 166
 167                 if [ -z "${mountp}" ]
 168                 then
 169                         mountp="/mnt/tmp_fs_size"
 170
 171                         mkdir -p "${mountp}"
 172                         mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}" || log_warning_msg "cannot mount -t $(get_fstype ${dev}) -o ro ${dev} ${mountp}"
 173
 174                         doumount=1
 175                 fi
 176         fi
 177
 178         if [ "${used}" = "used" ]
 179         then
 180                 size=$(du -ks ${mountp} | cut -f1)
 181                 size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
 182         else
 183                 # free space
 184                 size="$(df -k | grep -s ${mountp} | awk '{print $4}')"
 185         fi
 186
 187         if [ -n "${doumount}" ]
 188         then
 189                 umount "${mountp}" || log_warning_msg "cannot umount ${mountp}"
 190                 rmdir "${mountp}"
 191         fi
 192
 193         echo "${size}"
 194 }
 195
 196 load_keymap ()
 197 {
 198         # Load custom keymap
 199         if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
 200         then
 201                 loadkeys /etc/boottime.kmap.gz
 202         fi
 203 }
 204
 205 setup_loop ()
 206 {
 207         local fspath=${1}
 208         local module=${2}
 209         local pattern=${3}
 210         local offset=${4}
 211         local encryption=${5}
 212         local readonly=${6}
 213
 214         # the output of setup_loop is evaluated in other functions,
 215         # modprobe leaks kernel options like "libata.dma=0"
 216         # as "options libata dma=0" on stdout, causing serious
 217         # problems therefor, so instead always avoid output to stdout
 218         modprobe -q -b "${module}" 1>/dev/null
 219
 220         udevadm settle
 221
 222         for loopdev in ${pattern}
 223         do
 224                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 225                 then
 226                         dev=$(sys2dev "${loopdev}")
 227                         options=''
 228
 229                         if [ -n "${readonly}" ]
 230                         then
 231                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 232                                 then
 233                                         options="${options} -r"
 234                                 fi
 235                         fi
 236
 237                         if [ -n "${offset}" ] && [ 0 -lt "${offset}" ]
 238                         then
 239                                 options="${options} -o ${offset}"
 240                         fi
 241
 242                         if [ -z "${encryption}" ]
 243                         then
 244                                 losetup ${options} "${dev}" "${fspath}"
 245                         else
 246                                 # Loop AES encryption
 247                                 while true
 248                                 do
 249                                         load_keymap
 250
 251                                         echo -n "Enter passphrase for root filesystem: " >&6
 252                                         read -s passphrase
 253                                         echo "${passphrase}" > /tmp/passphrase
 254                                         unset passphrase
 255                                         exec 9</tmp/passphrase
 256                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 257                                         error=${?}
 258                                         exec 9<&-
 259                                         rm -f /tmp/passphrase
 260
 261                                         if [ 0 -eq ${error} ]
 262                                         then
 263                                                 unset error
 264                                                 break
 265                                         fi
 266
 267                                         echo
 268                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 269                                         read answer
 270
 271                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 272                                         then
 273                                                 unset answer
 274                                                 break
 275                                         fi
 276                                 done
 277                         fi
 278
 279                         echo "${dev}"
 280                         return 0
 281                 fi
 282         done
 283
 284         panic "No loop devices available"
 285 }
 286
 287 try_mount ()
 288 {
 289         dev="${1}"
 290         mountp="${2}"
 291         opts="${3}"
 292         fstype="${4}"
 293
 294         old_mountp="$(where_is_mounted ${dev})"
 295
 296         if [ -n "${old_mountp}" ]
 297         then
 298                 if [ "${opts}" != "ro" ]
 299                 then
 300                         mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
 301                 fi
 302
 303                 mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
 304         else
 305                 if [ -z "${fstype}" ]
 306                 then
 307                         fstype=$(get_fstype "${dev}")
 308                 fi
 309                 mount -t "${fstype}" -o "${opts}" "${dev}" "${mountp}" || \
 310                 ( echo "SKIPPING: Cannot mount ${dev} on ${mountp}, fstype=${fstype}, options=${opts}" > live-boot.log && return 0 )
 311         fi
 312 }
 313
 314 open_luks_device ()
 315 {
 316         dev="${1}"
 317         name="$(basename ${dev})"
 318         opts="--key-file=-"
 319         if [ -n "${PERSISTENT_READONLY}" ]
 320         then
 321                 opts="${opts} --readonly"
 322         fi
 323
 324         load_keymap
 325
 326         while true
 327         do
 328                 /lib/cryptsetup/askpass "Enter passphrase for ${dev}: " | \
 329                         /sbin/cryptsetup -T 1 luksOpen ${dev} ${name} ${opts}
 330
 331                 if [ 0 -eq ${?} ]
 332                 then
 333                         luks_device="/dev/mapper/${name}"
 334                         echo ${luks_device}
 335                         return 0
 336                 fi
 337
 338                 echo >&6
 339                 echo -n "There was an error decrypting ${dev} ... Retry? [Y/n] " >&6
 340                 read answer
 341
 342                 if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 343                 then
 344                         return 2
 345                 fi
 346         done
 347 }
 348
 349 find_persistent_media ()
 350 {
 351         # Scans devices for overlays and snapshots, and returns a whitespace
 352         # separated list of how to use them. Only overlays with a partition
 353         # label or file name in ${overlays} are returned, and ditto for
 354         # snapshots with labels in ${snapshots}.
 355         #
 356         # When scanning a LUKS device, the user will be asked to enter the
 357         # passphrase; on failure to enter it, or if no persistent partitions
 358         # or files were found, the LUKS device is closed.
 359         #
 360         # For a snapshot file the return value is ${label}=${snapdata}", where
 361         # ${snapdata} is the parameter used for try_snap().
 362         #
 363         # For all other cases (overlay/snapshot partition and overlay file) the
 364         # return value is "${label}=${device}", where ${device} a device that
 365         # can mount the content. In the case of an overlay file, the device
 366         # containing the file will remain mounted as a side-effect.
 367         #
 368         # No devices in ${black_listed_devices} will be scanned, and if
 369         # ${white_list_devices} is non-empty, only devices in it will be
 370         # scanned.
 371
 372         overlays="${1}"
 373         snapshots="${2}"
 374         black_listed_devices="${3}"
 375         white_listed_devices="${4}"
 376
 377         for dev in $(storage_devices "${black_listed_devices}" "${white_listed_devices}")
 378         do
 379                 luks_device=""
 380
 381                 # Checking for a luks device
 382                 if echo ${PERSISTENT_ENCRYPTION} | grep -qe "\<luks\>" && \
 383                    /sbin/cryptsetup isLuks ${dev}
 384                 then
 385                         if luks_device=$(open_luks_device "${dev}")
 386                         then
 387                                 dev="${luks_device}"
 388                         else
 389                                 # skip $dev since we failed/chose not to open it
 390                                 continue
 391                         fi
 392                 elif echo ${PERSISTENT_ENCRYPTION} | grep -qve "\<none\>"
 393                 then
 394                         # skip $dev since we don't allow unencrypted storage
 395                         continue
 396                 fi
 397
 398                 if echo ${PERSISTENT_STORAGE} | grep -qe "\<filesystem\>"
 399                 then
 400                         for label in ${overlays} ${snapshots}
 401                         do
 402                                 if [ "$(/sbin/blkid -s LABEL -o value $dev 2>/dev/null)" = "${label}" ]
 403                                 then
 404                                         overlays=$(echo ${overlays} | sed -e "s|\<${label}\>||")
 405                                         snapshots=$(echo ${snapshots} | sed -e "s|\<${label}\>||")
 406                                         echo "${label}=${dev}"
 407                                         # skip to the next device
 408                                         continue 2
 409                                 fi
 410                         done
 411                 fi
 412
 413                 if echo ${PERSISTENT_STORAGE} | grep -qe "\<file\>"
 414                 then
 415                         devfstype="$(get_fstype ${dev})"
 416                         overlay_on_dev=""
 417                         snapshot_on_dev=""
 418                         backing="/$(basename ${dev})-backing"
 419                         mkdir -p "${backing}"
 420                         if is_supported_fs ${devfstype} && try_mount "${dev}" "${backing}" "rw" "${devfstype}"
 421                         then
 422                                 for label in ${overlays}
 423                                 do
 424                                         path=${backing}/${PERSISTENT_PATH}${label}
 425                                         if [ -f "${path}" ]
 426                                         then
 427                                                 overlays=$(echo ${overlays} | sed -e "s|\<${label}\>||")
 428                                                 overlay_on_dev="yes"
 429                                                 echo "${label}=$(setup_loop "${path}" "loop" "/sys/block/loop*")"
 430                                         fi
 431                                 done
 432
 433                                 for label in ${snapshots}
 434                                 do
 435                                         for ext in squashfs cpio.gz ext2 ext3 ext4 jffs2
 436                                         do
 437                                                 path="${PERSISTENT_PATH}${label}.${ext}"
 438                                                 if [ -f "${backing}/${path}" ]
 439                                                 then
 440                                                         snapshots=$(echo ${snapshots} | sed -e "s|\<${label}\>||")
 441                                                         snapshot_on_dev="yes"
 442                                                         echo "${label}=${dev}:${backing}:${path}"
 443                                                 fi
 444                                         done
 445                                 done
 446                         fi
 447                         if [ -z "${overlay_on_dev}" ]
 448                         then
 449                                 umount ${backing} > /dev/null 2>&1 || true
 450                                 if [ -z "${snapshot_on_dev}" ] && [ -n "${luks_device}" ] && /sbin/cryptsetup status "${luks_device}" 1> /dev/null
 451                                 then
 452                                         /sbin/cryptsetup luksClose "${luks_device}"
 453                                 fi
 454                         fi
 455                 fi
 456         done
 457 }
 458
 459 get_mac ()
 460 {
 461         mac=""
 462
 463         for adaptor in /sys/class/net/*
 464         do
 465                 status="$(cat ${adaptor}/iflink)"
 466
 467                 if [ "${status}" -eq 2 ]
 468                 then
 469                         mac="$(cat ${adaptor}/address)"
 470                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
 471                 fi
 472         done
 473
 474         echo ${mac}
 475 }
 476
 477 is_luks()
 478 {
 479     devname="${1}"
 480     if [ -x /sbin/cryptsetup ]
 481     then
 482         /sbin/cryptsetup isLuks "${devname}" 2>/dev/null || ret=${?}
 483         return ${ret}
 484     else
 485         return 1
 486     fi
 487
 488 }
 489
 490 removable_dev ()
 491 {
 492         output_format="${1}"
 493         want_usb="${2}"
 494         ret=
 495
 496         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
 497         do
 498                 dev_ok=
 499                 if [ "$(cat ${sysblock}/removable)" = "1" ]
 500                 then
 501                         if [ -z "${want_usb}" ]
 502                         then
 503                                 dev_ok="yes"
 504                         else
 505                                 if readlink ${sysblock} | grep -q usb
 506                                 then
 507                                         dev_ok="yes"
 508                                 fi
 509                         fi
 510                 fi
 511
 512                 if [ "${dev_ok}" = "yes" ]
 513                 then
 514                         case "${output_format}" in
 515                                 sys)
 516                                         ret="${ret} ${sysblock}"
 517                                         ;;
 518                                 *)
 519                                         devname=$(sys2dev "${sysblock}")
 520                                         ret="${ret} ${devname}"
 521                                         ;;
 522                         esac
 523                 fi
 524         done
 525
 526         echo "${ret}"
 527 }
 528
 529 removable_usb_dev ()
 530 {
 531         output_format="${1}"
 532
 533         removable_dev "${output_format}" "want_usb"
 534 }
 535
 536 non_removable_dev ()
 537 {
 538         output_format="${1}"
 539         ret=
 540
 541         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
 542         do
 543                 if [ "$(cat ${sysblock}/removable)" = "0" ]
 544                 then
 545                         case "${output_format}" in
 546                                 sys)
 547                                         ret="${ret} ${sysblock}"
 548                                         ;;
 549                                 *)
 550                                         devname=$(sys2dev "${sysblock}")
 551                                         ret="${ret} ${devname}"
 552                                         ;;
 553                         esac
 554                 fi
 555         done
 556
 557         echo "${ret}"
 558 }
 559
 560 link_files ()
 561 {
 562         # create source's directory structure in dest, and recursively
 563         # create symlinks in dest to to all files in source. if mask
 564         # is non-empty, remove mask from all source paths when
 565         # creating links (will be necessary if we change root, which
 566         # live-boot normally does (into $rootmnt)).
 567
 568         # remove multiple /:s and ensure ending on /
 569         local src_dir="$(echo "${1}"/ | sed -e 's|/\+|/|g')"
 570         local dest_dir="$(echo "${2}"/ | sed -e 's|/\+|/|g')"
 571         local src_mask="${3}"
 572
 573         # This check can only trigger on the inital, non-recursive call since
 574         # we create the destination before recursive calls
 575         if [ ! -d "${dest_dir}" ];
 576         then
 577                 log_warning_msg "Must link_files into a directory"
 578                 return
 579         fi
 580
 581         find "${src_dir}" -mindepth 1 -maxdepth 1 | while read x; do
 582                 local src="${x}"
 583                 local dest="${dest_dir}$(basename "${x}")"
 584                 if [ -d "${src}" ];
 585                 then
 586                         if [ -z "$(ls -A "${src}")" ];
 587                         then
 588                                 continue
 589                         fi
 590                         if [ ! -d "${dest}" ];
 591                         then
 592                                 mkdir -p "${dest}"
 593                                 prev="$(dirname "${dest}")"
 594                                 chown $(stat -c %u:%g "${prev}") "${dest}"
 595                                 chmod $(stat -c %a "${prev}") "${dest}"
 596                         fi
 597                         link_files "${src}" "${dest}" "${src_mask}"
 598                 else
 599                         if [ -n "${src_mask}" ]
 600                         then
 601                                 src="$(echo ${src} | sed "s|^${src_mask}||")"
 602                         fi
 603                         rm -rf "${dest}" 2> /dev/null
 604                         ln -s "${src}" "${dest}"
 605                 fi
 606         done
 607 }
 608
 609 do_union () {
 610         local unionmountpoint="${1}"    # directory where the union is mounted
 611         local unionrw="${2}"            # branch where the union changes are stored
 612         local unionro1="${3}"           # first underlying read-only branch (optional)
 613         local unionro2="${4}"           # second underlying read-only branch (optional)
 614
 615         if [ "${UNIONTYPE}" = "aufs" ]
 616         then
 617                 rw_opt="rw"
 618                 ro_opt="rr+wh"
 619                 noxino_opt="noxino"
 620         elif [ "${UNIONTYPE}" = "unionfs-fuse" ]
 621         then
 622                 rw_opt="RW"
 623                 ro_opt="RO"
 624         else
 625                 rw_opt="rw"
 626                 ro_opt="ro"
 627         fi
 628
 629         case "${UNIONTYPE}" in
 630                 unionfs-fuse)
 631                         unionmountopts="-o cow -o noinitgroups -o default_permissions -o allow_other -o use_ino -o suid"
 632                         unionmountopts="${unionmountopts} ${unionrw}=${rw_opt}"
 633                         if [ -n "${unionro1}" ]
 634                         then
 635                                 unionmountopts="${unionmountopts}:${unionro1}=${ro_opt}"
 636                         fi
 637                         if [ -n "${unionro2}" ]
 638                         then
 639                                 unionmountopts="${unionmountopts}:${unionro2}=${ro_opt}"
 640                         fi
 641                         ( sysctl -w fs.file-max=391524 ; ulimit -HSn 16384
 642                         unionfs-fuse ${unionmountopts} "${unionmountpoint}" ) && \
 643                         ( mkdir -p /run/sendsigs.omit.d
 644                         pidof unionfs-fuse >> /run/sendsigs.omit.d/unionfs-fuse || true )
 645                         ;;
 646
 647                 overlayfs)
 648                         # XXX: can unionro2 be used? (overlayfs only handles two dirs, but perhaps they can be chained?)
 649                         # XXX: and can unionro1 be optional? i.e. can overlayfs skip lowerdir?
 650                         unionmountopts="-o noatime,lowerdir=${unionro1},upperdir=${unionrw}"
 651                         mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
 652                         ;;
 653
 654                 *)
 655                         unionmountopts="-o noatime,${noxino_opt},dirs=${unionrw}=${rw_opt}"
 656                         if [ -n "${unionro1}" ]
 657                         then
 658                                 unionmountopts="${unionmountopts}:${unionro1}=${ro_opt}"
 659                         fi
 660                         if [ -n "${unionro2}" ]
 661                         then
 662                                 unionmountopts="${unionmountopts}:${unionro2}=${ro_opt}"
 663                         fi
 664                         mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
 665                         ;;
 666         esac
 667 }
 668
 669 get_custom_mounts () {
 670         # Side-effect: leaves $devices with live.persist mounted in ${rootmnt}/live/persistent
 671         # Side-effect: prints info to file $custom_mounts
 672
 673         local devices="${1}"
 674         local custom_mounts="${2}" # print result to this file
 675         local rootmnt="${3}"       # should be set empty post-live-boot
 676
 677         local bindings="/bindings.list"
 678         local links="/links.list"
 679         rm -rf ${bindings} ${links} 2> /dev/null
 680         local persistent_backing="${rootmnt}/live/persistent"
 681
 682         for device in ${devices}
 683         do
 684                 if [ ! -b "${device}" ]
 685                 then
 686                         continue
 687                 fi
 688                 local device_name="$(basename ${device})"
 689                 local backing="${persistent_backing}/${device_name}"
 690                 mkdir -p "${backing}"
 691                 local device_fstype="$(get_fstype ${device})"
 692                 if [ -z "${PERSISTENT_READONLY}" ]
 693                 then
 694                         device_mount_opts="rw,noatime"
 695                 else
 696                         device_mount_opts="ro,noatime"
 697                 fi
 698                 local device_used=""
 699                 mount -t "${device_fstype}" -o "${device_mount_opts}" "${device}" "${backing}"
 700                 local include_list="${backing}/${persistence_list}"
 701                 if [ ! -r "${include_list}" ]
 702                 then
 703                         umount "${backing}"
 704                         rmdir "${backing}"
 705                         continue
 706                 fi
 707
 708                 [ "${DEBUG}" = "Yes" ] && cp ${include_list} ${persistent_backing}/${persistence_list}.${device_name}
 709                 while read source dest options # < ${include_list}
 710                 do
 711                         if echo ${source} | grep -qe "^[[:space:]]*\(#.*\)\?$"
 712                         then
 713                                 # skipping empty or commented lines
 714                                 continue
 715                         fi
 716
 717                         if echo ${dest} | grep -qe "^[^/]"
 718                         then
 719                                 options="${dest}"
 720                                 dest="${source}"
 721                         elif [ -z "${dest}" ]
 722                         then
 723                                 dest="${source}"
 724                         fi
 725
 726                         if echo ${dest} | grep -qe "^/\+$\|^/\+live\(/.*\)\?$"
 727                         then
 728                                 # mounting on / or /live could cause trouble
 729                                 log_warning_msg "Skipping unsafe custom mount on ${dest}"
 730                                 continue
 731                         fi
 732
 733                         for opt in $(echo ${options} | tr ',' ' ');
 734                         do
 735                                 case "${opt}" in
 736                                         linkfiles|union)
 737                                                 ;;
 738                                         *)
 739                                                 log_warning_msg "Skipping custom mount with unkown option: ${opt}"
 740                                                 continue 2
 741                                                 ;;
 742                                 esac
 743                         done
 744
 745                         # FIXME: handle case: we already have /a/b in
 746                         # $bindings added from current $device, but
 747                         # now we find /a -- /a should replace /a/b in
 748                         # $bindings.
 749
 750                         # FIXME: handle case: we have /a in $bindings
 751                         # from current $device, now we find /a/b, so
 752                         # we skip /a/b
 753
 754                         # ensure that no multiple-/ occur in paths
 755                         local full_source="$(echo ${backing}/${source}/ | sed -e 's|/\+|/|g')"
 756                         local full_dest="$(echo ${rootmnt}/${dest}/ | sed -e 's|/\+|/|g')"
 757                         device_used="yes"
 758                         if echo ${options} | grep -qe "\<linkfiles\>";
 759                         then
 760                                 echo "${full_source} ${full_dest} ${options}" >> ${links}
 761                         else
 762                                 echo "${full_source} ${full_dest} ${options}" >> ${bindings}
 763                         fi
 764                 done < ${include_list}
 765
 766                 if [ -z "${device_used}" ]
 767                 then
 768                         # this device was not used for / earlier, or
 769                         # custom mount point now, so it's useless
 770                         umount "${backing}"
 771                         rmdir "${backing}"
 772                 fi
 773         done
 774
 775         # We sort the list according to destination so we're sure that
 776         # we won't hide a previous mount. We also ignore duplicate
 777         # destinations in a more or less arbitrary way.
 778         [ -e "${bindings}" ] && sort -k2 -sbu ${bindings} >> ${custom_mounts}
 779         rm ${bindings}
 780
 781         # After all mounts are considered we add symlinks so they
 782         # won't be hidden by some mount.
 783         [ -e "${links}" ] && sort -k2 -sbu ${links} >> ${custom_mounts}
 784         rm ${links}
 785
 786         rm -f ${bindings} ${links} 2> /dev/null
 787         echo ${custom_mounts}
 788 }
 789
 790 do_custom_mounts () {
 791         local custom_mounts="${1}" # the ouput from get_custom_mounts()
 792         local rootmnt="${2}"       # should be set empty post-live-boot
 793
 794         while read source dest options # < ${custom_mounts}
 795         do
 796                 local opt_linkfiles=""
 797                 local opt_union=""
 798                 for opt in $(echo ${options} | tr ',' ' ');
 799                 do
 800                          case "${opt}" in
 801                                 linkfiles)
 802                                         opt_linkfiles="yes"
 803                                         ;;
 804                                 union)
 805                                         opt_union="yes"
 806                                         ;;
 807                         esac
 808                 done
 809
 810                 if mountpoint -q "${dest}";
 811                 then
 812                         log_warning_msg "Skipping custom mount ${source} on ${dest}: destination is already a mount point"
 813                         continue
 814                 fi
 815
 816                 # FIXME: we don't handle already existing
 817                 # non-directory files in the paths of both $source and
 818                 # $dest.
 819
 820                 if [ ! -d "${dest}" ]
 821                 then
 822                         # if ${dest} is in /home/$user, try fixing
 823                         # proper ownership
 824                         # FIXME: this should really be handled by
 825                         # live-config since we don't know for sure
 826                         # which uid a certain user has until then
 827                         if echo ${dest} | grep -qe "^${rootmnt}/*home/\+[^/]\+"
 828                         then
 829                                 path="/"
 830                                 for dir in $(echo ${dest} | sed -e 's|/\+| |g')
 831                                 do
 832                                         path=${path}/${dir}
 833                                         if [ ! -e ${path} ]
 834                                         then
 835                                                 mkdir -p ${path}
 836                                                 # assume that the intended user is the first, which is usually the case
 837                                                 chown 1000:1000 ${path}
 838                                         fi
 839                                 done
 840                         else
 841                                 mkdir -p ${dest}
 842                         fi
 843                 fi
 844
 845                 # if ${source} doesn't exist on our persistent media
 846                 # we bootstrap it with $dest from the live filesystem.
 847                 # this both makes sense and is critical if we're
 848                 # dealing with /etc or other system dir.
 849                 if [ ! -d "${source}" ]
 850                 then
 851                         if [ -n "${PERSISTENT_READONLY}" ] || [ -n "${opt_linkfiles}" ]
 852                         then
 853                                 continue
 854                         elif [ -n "${opt_union}" ]
 855                         then
 856                                 # union's don't need to be bootstrapped
 857                                 mkdir "${source}"
 858                         else
 859                                 # ensure that $dest is not copied *into* $source
 860                                 mkdir -p "$(dirname ${source})"
 861                                 cp -a "${dest}" "${source}"
 862                         fi
 863                 fi
 864
 865                 rofs_dest_backing=""
 866                 for d in ${rootmnt}/live/rofs/*
 867                 do
 868                         if [ -n "${rootmnt}" ]
 869                         then
 870                                 rofs_dest_backing="${d}/$(echo ${dest} | sed -e "s|${rootmnt}||")"
 871                         else
 872                                 rofs_dest_backing="${d}/${dest}"
 873
 874                         fi
 875                         if [ -d "${rofs_dest_backing}" ]
 876                         then
 877                                 break
 878                         else
 879                                 rofs_dest_backing=""
 880                         fi
 881                 done
 882
 883                 if [ -z "${PERSISTENT_READONLY}" ]
 884                 then
 885                         if [ -n "${opt_linkfiles}" ]
 886                         then
 887                                 links_source="${source}"
 888                                 links_dest="${dest}"
 889                         elif [ -n "${opt_union}" ]
 890                         then
 891                                 do_union ${dest} ${source} ${rofs_dest_backing}
 892                         else
 893                                 mount --bind "${source}" "${dest}"
 894                         fi
 895                 else
 896                         if [ -n "${opt_linkfiles}" ]
 897                         then
 898                                 links_dest="${dest}"
 899                                 dest="$(mktemp -d ${persistent_backing}/links_source-XXXXXX)"
 900                                 links_source="${dest}"
 901                         fi
 902                         if [ -n "${rootmnt}" ]
 903                         then
 904                                 cow_dir="$(echo ${dest} | sed -e "s|${rootmnt}|/cow/|")"
 905                         else
 906                                 cow_dir="/live/cow/${dest}"
 907                         fi
 908                         mkdir -p ${cow_dir}
 909                         do_union ${dest} ${cow_dir} ${source} ${rofs_dest_backing}
 910                 fi
 911
 912                 if [ -n "${opt_linkfiles}" ]
 913                 then
 914                         link_files "${links_source}" "${links_dest}" "${rootmnt}"
 915                 fi
 916
 917                 PERSISTENCE_IS_ON="1"
 918                 export PERSISTENCE_IS_ON
 919         done < ${custom_mounts}
 920 }