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 old_root_overlay_label="live-rw"
  19 old_home_overlay_label="home-rw"
  20 custom_overlay_label="custom-ov"
  21 root_snapshot_label="live-sn"
  22 old_root_snapshot_label="live-sn"
  23 home_snapshot_label="home-sn"
  24 persistence_list="live-persistence.conf"
  25
  26 Arguments ()
  27 {
  28         PRESEEDS=""
  29         LOCATIONS=""
  30
  31         for ARGUMENT in $(cat /proc/cmdline)
  32         do
  33                 case "${ARGUMENT}" in
  34                         skipconfig)
  35                                 NOACCESSIBILITY="Yes"
  36                                 NOFASTBOOT="Yes"
  37                                 NOFSTAB="Yes"
  38                                 NONETWORKING="Yes"
  39
  40                                 export NOACCESSIBILITY NOFASTBOOT NOFSTAB NONETWORKING
  41                                 ;;
  42
  43                         access=*)
  44                                 ACCESS="${ARGUMENT#access=}"
  45                                 export ACCESS
  46                                 ;;
  47
  48                         console=*)
  49                                 DEFCONSOLE="${ARGUMENT#*=}"
  50                                 export DEFCONSOLE
  51                                 ;;
  52
  53                         BOOTIF=*)
  54                                 BOOTIF="${x#BOOTIF=}"
  55                                 ;;
  56
  57                         debug)
  58                                 DEBUG="Yes"
  59                                 export DEBUG
  60
  61                                 set -x
  62                                 ;;
  63
  64                         dhcp)
  65                                 # Force dhcp even while netbooting
  66                                 # Use for debugging in case somebody works on fixing dhclient
  67                                 DHCP="Force";
  68                                 export DHCP
  69                                 ;;
  70
  71                         nodhcp)
  72                                 unset DHCP
  73                                 ;;
  74
  75                         ethdevice=*)
  76                                 DEVICE="${ARGUMENT#ethdevice=}"
  77                                 ETHDEVICE="${DEVICE}"
  78                                 export DEVICE ETHDEVICE
  79                                 ;;
  80
  81                         ethdevice-timeout=*)
  82                                 ETHDEV_TIMEOUT="${ARGUMENT#ethdevice-timeout=}"
  83                                 export ETHDEV_TIMEOUT
  84                                 ;;
  85
  86                         fetch=*)
  87                                 FETCH="${ARGUMENT#fetch=}"
  88                                 export FETCH
  89                                 ;;
  90
  91                         findiso=*)
  92                                 FINDISO="${ARGUMENT#findiso=}"
  93                                 export FINDISO
  94                                 ;;
  95
  96                         forcepersistencefsck)
  97                                 FORCEPERSISTENCEFSCK="Yes"
  98                                 export FORCEPERSISTENCEFSCK
  99                                 ;;
 100
 101                         ftpfs=*)
 102                                 FTPFS="${ARGUMENT#ftpfs=}"
 103                                 export FTPFS
 104                                 ;;
 105
 106                         httpfs=*)
 107                                 HTTPFS="${ARGUMENT#httpfs=}"
 108                                 export HTTPFS
 109                                 ;;
 110
 111                         iscsi=*)
 112                                 ISCSI="${ARGUMENT#iscsi=}"
 113                                 #ip:port - separated by ;
 114                                 ISCSI_PORTAL="${ISCSI%;*}"
 115                                 if echo "${ISCSI_PORTAL}" | grep -q , ; then
 116                                         ISCSI_SERVER="${ISCSI_PORTAL%,*}"
 117                                         ISCSI_PORT="${ISCSI_PORTAL#*,}"
 118                                 fi
 119                                 #target name
 120                                 ISCSI_TARGET="${ISCSI#*;}"
 121                                 export ISCSI ISCSI_PORTAL ISCSI_TARGET ISCSI_SERVER ISCSI_PORT
 122                                 ;;
 123
 124                         isofrom=*|fromiso=*)
 125                                 FROMISO="${ARGUMENT#*=}"
 126                                 export FROMISO
 127                                 ;;
 128
 129                         ignore_uuid)
 130                                 IGNORE_UUID="Yes"
 131                                 export IGNORE_UUID
 132                                 ;;
 133
 134                         integrity-check)
 135                                 INTEGRITY_CHECK="Yes"
 136                                 export INTEGRITY_CHECK
 137                                 ;;
 138
 139                         ip=*)
 140                                 STATICIP="${ARGUMENT#ip=}"
 141
 142                                 if [ -z "${STATICIP}" ]
 143                                 then
 144                                         STATICIP="frommedia"
 145                                 fi
 146
 147                                 export STATICIP
 148                                 ;;
 149
 150                         live-getty)
 151                                 LIVE_GETTY="1"
 152                                 export LIVE_GETTY
 153                                 ;;
 154
 155                         live-media=*|bootfrom=*)
 156                                 LIVE_MEDIA="${ARGUMENT#*=}"
 157                                 export LIVE_MEDIA
 158                                 ;;
 159
 160                         live-media-encryption=*|encryption=*)
 161                                 LIVE_MEDIA_ENCRYPTION="${ARGUMENT#*=}"
 162                                 export LIVE_MEDIA_ENCRYPTION
 163                                 ;;
 164
 165                         live-media-offset=*)
 166                                 LIVE_MEDIA_OFFSET="${ARGUMENT#live-media-offset=}"
 167                                 export LIVE_MEDIA_OFFSET
 168                                 ;;
 169
 170                         live-media-path=*)
 171                                 LIVE_MEDIA_PATH="${ARGUMENT#live-media-path=}"
 172                                 export LIVE_MEDIA_PATH
 173                                 ;;
 174
 175                         live-media-timeout=*)
 176                                 LIVE_MEDIA_TIMEOUT="${ARGUMENT#live-media-timeout=}"
 177                                 export LIVE_MEDIA_TIMEOUT
 178                                 ;;
 179
 180                         module=*)
 181                                 MODULE="${ARGUMENT#module=}"
 182                                 export MODULE
 183                                 ;;
 184
 185                         netboot=*)
 186                                 NETBOOT="${ARGUMENT#netboot=}"
 187                                 export NETBOOT
 188                                 ;;
 189
 190                         nfsopts=*)
 191                                 NFSOPTS="${ARGUMENT#nfsopts=}"
 192                                 export NFSOPTS
 193                                 ;;
 194
 195                         nfsoverlay=*)
 196                                 NFS_COW="${ARGUMENT#nfsoverlay=}"
 197                                 export NFS_COW
 198                                 ;;
 199
 200                         noaccessibility)
 201                                 NOACCESSIBILITY="Yes"
 202                                 export NOACCESSIBILITY
 203                                 ;;
 204
 205                         nofastboot)
 206                                 NOFASTBOOT="Yes"
 207                                 export NOFASTBOOT
 208                                 ;;
 209
 210                         nofstab)
 211                                 NOFSTAB="Yes"
 212                                 export NOFSTAB
 213                                 ;;
 214
 215                         nonetworking)
 216                                 NONETWORKING="Yes"
 217                                 export NONETWORKING
 218                                 ;;
 219
 220                         ramdisk-size=*)
 221                                 ramdisk_size="${ARGUMENT#ramdisk-size=}"
 222                                 ;;
 223
 224                         swapon)
 225                                 SWAPON="Yes"
 226                                 export SWAPON
 227                                 ;;
 228
 229                         persistence)
 230                                 PERSISTENCE="Yes"
 231                                 export PERSISTENCE
 232                                 ;;
 233
 234                         persistence-encryption=*)
 235                                 PERSISTENCE_ENCRYPTION="${ARGUMENT#*=}"
 236                                 export PERSISTENCE_ENCRYPTION
 237                                 ;;
 238
 239                         persistence-media=*)
 240                                 PERSISTENCE_MEDIA="${ARGUMENT#*=}"
 241                                 export PERSISTENCE_MEDIA
 242                                 ;;
 243                         persistence-method=*)
 244                                 PERSISTENCE_METHOD="${ARGUMENT#*=}"
 245                                 export PERSISTENCE_METHOD
 246                                 ;;
 247
 248                         persistence-path=*)
 249                                 PERSISTENCE_PATH="${ARGUMENT#persistence-path=}"
 250                                 export PERSISTENCE_PATH
 251                                 ;;
 252                         persistence-read-only)
 253                                 PERSISTENCE_READONLY="Yes"
 254                                 export PERSISTENCE_READONLY
 255                                 ;;
 256
 257                         persistence-storage=*)
 258                                 PERSISTENCE_STORAGE="${ARGUMENT#persistence-storage=}"
 259                                 export PERSISTENCE_STORAGE
 260                                 ;;
 261
 262                         persistence-subtext=*)
 263                                 old_root_overlay_label="${old_root_overlay_label}-${ARGUMENT#persistence-subtext=}"
 264                                 old_home_overlay_label="${old_home_overlay_label}-${ARGUMENT#persistence-subtext=}"
 265                                 custom_overlay_label="${custom_overlay_label}-${ARGUMENT#persistence-subtext=}"
 266                                 root_snapshot_label="${root_snapshot_label}-${ARGUMENT#persistence-subtext=}"
 267                                 old_root_snapshot_label="${root_snapshot_label}-${ARGUMENT#persistence-subtext=}"
 268                                 home_snapshot_label="${home_snapshot_label}-${ARGUMENT#persistence-subtext=}"
 269                                 ;;
 270
 271                         nopersistence)
 272                                 NOPERSISTENCE="Yes"
 273                                 export NOPERSISTENCE
 274                                 ;;
 275
 276                         noprompt)
 277                                 NOPROMPT="Yes"
 278                                 export NOPROMPT
 279                                 ;;
 280
 281                         noprompt=*)
 282                                 NOPROMPT="${ARGUMENT#noprompt=}"
 283                                 export NOPROMPT
 284                                 ;;
 285
 286                         quickusbmodules)
 287                                 QUICKUSBMODULES="Yes"
 288                                 export QUICKUSBMODULES
 289                                 ;;
 290
 291                         preseed/file=*|file=*)
 292                                 LOCATIONS="${ARGUMENT#*=} ${LOCATIONS}"
 293                                 export LOCATIONS
 294                                 ;;
 295
 296                         nopreseed)
 297                                 NOPRESEED="Yes"
 298                                 export NOPRESEED
 299                                 ;;
 300
 301                         */*=*)
 302                                 question="${ARGUMENT%%=*}"
 303                                 value="${ARGUMENT#*=}"
 304                                 PRESEEDS="${PRESEEDS}\"${question}=${value}\" "
 305                                 export PRESEEDS
 306                                 ;;
 307
 308                         showmounts)
 309                                 SHOWMOUNTS="Yes"
 310                                 export SHOWMOUNTS
 311                                 ;;
 312
 313                         silent)
 314                                 SILENT="Yes"
 315                                 export SILENT
 316                                 ;;
 317
 318                         todisk=*)
 319                                 TODISK="${ARGUMENT#todisk=}"
 320                                 export TODISK
 321                                 ;;
 322
 323                         toram)
 324                                 TORAM="Yes"
 325                                 export TORAM
 326                                 ;;
 327
 328                         toram=*)
 329                                 TORAM="Yes"
 330                                 MODULETORAM="${ARGUMENT#toram=}"
 331                                 export TORAM MODULETORAM
 332                                 ;;
 333
 334                         exposedroot)
 335                                 EXPOSED_ROOT="Yes"
 336                                 export EXPOSED_ROOT
 337                                 ;;
 338
 339                         plainroot)
 340                                 PLAIN_ROOT="Yes"
 341                                 export PLAIN_ROOT
 342                                 ;;
 343
 344                         skipunion)
 345                                 SKIP_UNION_MOUNTS="Yes"
 346                                 export SKIP_UNION_MOUNTS
 347                                 ;;
 348
 349                         root=*)
 350                                 ROOT="${ARGUMENT#root=}"
 351                                 export ROOT
 352                                 ;;
 353
 354                         union=*)
 355                                 UNIONTYPE="${ARGUMENT#union=}"
 356                                 export UNIONTYPE
 357                                 ;;
 358                 esac
 359         done
 360
 361         # sort of compatibility with netboot.h from linux docs
 362         if [ -z "${NETBOOT}" ]
 363         then
 364                 if [ "${ROOT}" = "/dev/nfs" ]
 365                 then
 366                         NETBOOT="nfs"
 367                         export NETBOOT
 368                 elif [ "${ROOT}" = "/dev/cifs" ]
 369                 then
 370                         NETBOOT="cifs"
 371                         export NETBOOT
 372                 fi
 373         fi
 374
 375         if [ -z "${MODULE}" ]
 376         then
 377                 MODULE="filesystem"
 378                 export MODULE
 379         fi
 380
 381         if [ -z "${UNIONTYPE}" ]
 382         then
 383                 UNIONTYPE="aufs"
 384                 export UNIONTYPE
 385         fi
 386
 387         if [ -z "${PERSISTENCE_ENCRYPTION}" ]
 388         then
 389                 PERSISTENCE_ENCRYPTION="none"
 390                 export PERSISTENCE_ENCRYPTION
 391         elif echo ${PERSISTENCE_ENCRYPTION} | grep -qe "\<luks\>"
 392         then
 393                 if ! modprobe dm-crypt
 394                 then
 395                         log_warning_msg "Unable to load module dm-crypt"
 396                         PERSISTENCE_ENCRYPTION=$(echo ${PERSISTENCE_ENCRYPTION} | sed -e 's/\<luks,\|,\?luks$//g')
 397                         export PERSISTENCE_ENCRYPTION
 398                 fi
 399
 400                 if [ ! -x /lib/cryptsetup/askpass ] || [ ! -x /sbin/cryptsetup ]
 401                 then
 402                         log_warning_msg "cryptsetup in unavailable"
 403                         PERSISTENCE_ENCRYPTION=$(echo ${PERSISTENCE_ENCRYPTION} | sed -e 's/\<luks,\|,\?luks$//g')
 404                         export PERSISTENCE_ENCRYPTION
 405                 fi
 406         fi
 407
 408         if [ -z "${PERSISTENCE_METHOD}" ]
 409         then
 410                 PERSISTENCE_METHOD="snapshot,overlay"
 411                 export PERSISTENCE_METHOD
 412         fi
 413
 414         if [ -z "${PERSISTENCE_STORAGE}" ]
 415         then
 416                 PERSISTENCE_STORAGE="filesystem,file"
 417                 export PERSISTENCE_STORAGE
 418         fi
 419 }
 420
 421 sys2dev ()
 422 {
 423         sysdev=${1#/sys}
 424         echo "/dev/$($udevinfo -q name -p ${sysdev} 2>/dev/null|| echo ${sysdev##*/})"
 425 }
 426
 427 subdevices ()
 428 {
 429         sysblock=${1}
 430         r=""
 431
 432         for dev in "${sysblock}"/* "${sysblock}"
 433         do
 434                 if [ -e "${dev}/dev" ]
 435                 then
 436                         r="${r} ${dev}"
 437                 fi
 438         done
 439
 440         echo ${r}
 441 }
 442
 443 storage_devices()
 444 {
 445         black_listed_devices="${1}"
 446         white_listed_devices="${2}"
 447
 448         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "loop|ram|fd")
 449         do
 450                 fulldevname=$(sys2dev "${sysblock}")
 451
 452                 if echo "${black_listed_devices}" | grep -qe "\<${fulldevname}\>" || \
 453                         [ -n "${white_listed_devices}" ] && \
 454                         echo "${white_listed_devices}" | grep -qve "\<${fulldevname}\>"
 455                 then
 456                         # skip this device entirely
 457                         continue
 458                 fi
 459
 460                 for dev in $(subdevices "${sysblock}")
 461                 do
 462                         devname=$(sys2dev "${dev}")
 463
 464                         if echo "${black_listed_devices}" | grep -qe "\<${devname}\>"
 465                         then
 466                                 # skip this subdevice
 467                                 continue
 468                         else
 469                                 echo "${devname}"
 470                         fi
 471                 done
 472         done
 473 }
 474
 475 is_supported_fs ()
 476 {
 477         fstype="${1}"
 478
 479         # Validate input first
 480         if [ -z "${fstype}" ]
 481         then
 482                 return 1
 483         fi
 484
 485         # Try to look if it is already supported by the kernel
 486         if grep -q ${fstype} /proc/filesystems
 487         then
 488                 return 0
 489         else
 490                 # Then try to add support for it the gentle way using the initramfs capabilities
 491                 modprobe ${fstype}
 492                 if grep -q ${fstype} /proc/filesystems
 493                 then
 494                         return 0
 495                 # Then try the hard way if /root is already reachable
 496                 else
 497                         kmodule="/root/lib/modules/`uname -r`/${fstype}/${fstype}.ko"
 498                         if [ -e "${kmodule}" ]
 499                         then
 500                                 insmod "${kmodule}"
 501                                 if grep -q ${fstype} /proc/filesystems
 502                                 then
 503                                         return 0
 504                                 fi
 505                         fi
 506                 fi
 507         fi
 508
 509         return 1
 510 }
 511
 512 get_fstype ()
 513 {
 514         /sbin/blkid -s TYPE -o value $1 2>/dev/null
 515 }
 516
 517 where_is_mounted ()
 518 {
 519         device=${1}
 520         # return first found
 521         grep -m1 "^${device} " /proc/mounts | cut -f2 -d ' '
 522 }
 523
 524 trim_path () {
 525     # remove all unnecessary /:s in the path, including last one (except
 526     # if path is just "/")
 527     echo ${1} | sed 's|//\+|/|g' | sed 's|^\(.*[^/]\)/$|\1|'
 528 }
 529
 530 what_is_mounted_on ()
 531 {
 532         local dir="$(trim_path ${1})"
 533         grep -m1 "^[^ ]\+ ${dir} " /proc/mounts | cut -d' ' -f1
 534 }
 535
 536 chown_ref ()
 537 {
 538         local reference="${1}"
 539         shift
 540         local targets=${@}
 541         local owner=$(stat -c %u:%g "${reference}")
 542         chown -h ${owner} ${targets}
 543 }
 544
 545 chmod_ref ()
 546 {
 547         local reference="${1}"
 548         shift
 549         local targets=${@}
 550         local rights=$(stat -c %a "${reference}")
 551         chmod ${rights} ${targets}
 552 }
 553
 554 lastline ()
 555 {
 556         while read lines
 557         do
 558                 line=${lines}
 559         done
 560
 561         echo "${line}"
 562 }
 563
 564 base_path ()
 565 {
 566         testpath="${1}"
 567         mounts="$(awk '{print $2}' /proc/mounts)"
 568         testpath="$(busybox realpath ${testpath})"
 569
 570         while true
 571         do
 572                 if echo "${mounts}" | grep -qs "^${testpath}"
 573                 then
 574                         set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
 575                         echo ${1}
 576                         break
 577                 else
 578                         testpath=$(dirname $testpath)
 579                 fi
 580         done
 581 }
 582
 583 fs_size ()
 584 {
 585         # Returns used/free fs kbytes + 5% more
 586         # You could pass a block device as ${1} or the mount point as ${2}
 587
 588         dev="${1}"
 589         mountp="${2}"
 590         used="${3}"
 591
 592         if [ -z "${mountp}" ]
 593         then
 594                 mountp="$(where_is_mounted ${dev})"
 595
 596                 if [ -z "${mountp}" ]
 597                 then
 598                         mountp="/mnt/tmp_fs_size"
 599
 600                         mkdir -p "${mountp}"
 601                         mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}" || log_warning_msg "cannot mount -t $(get_fstype ${dev}) -o ro ${dev} ${mountp}"
 602
 603                         doumount=1
 604                 fi
 605         fi
 606
 607         if [ "${used}" = "used" ]
 608         then
 609                 size=$(du -ks ${mountp} | cut -f1)
 610                 size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
 611         else
 612                 # free space
 613                 size="$(df -k | grep -s ${mountp} | awk '{print $4}')"
 614         fi
 615
 616         if [ -n "${doumount}" ]
 617         then
 618                 umount "${mountp}" || log_warning_msg "cannot umount ${mountp}"
 619                 rmdir "${mountp}"
 620         fi
 621
 622         echo "${size}"
 623 }
 624
 625 load_keymap ()
 626 {
 627         # Load custom keymap
 628         if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
 629         then
 630                 loadkeys /etc/boottime.kmap.gz
 631         fi
 632 }
 633
 634 setup_loop ()
 635 {
 636         local fspath=${1}
 637         local module=${2}
 638         local pattern=${3}
 639         local offset=${4}
 640         local encryption=${5}
 641         local readonly=${6}
 642
 643         # the output of setup_loop is evaluated in other functions,
 644         # modprobe leaks kernel options like "libata.dma=0"
 645         # as "options libata dma=0" on stdout, causing serious
 646         # problems therefor, so instead always avoid output to stdout
 647         modprobe -q -b "${module}" 1>/dev/null
 648
 649         udevadm settle
 650
 651         for loopdev in ${pattern}
 652         do
 653                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 654                 then
 655                         dev=$(sys2dev "${loopdev}")
 656                         options=''
 657
 658                         if [ -n "${readonly}" ]
 659                         then
 660                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 661                                 then
 662                                         options="${options} -r"
 663                                 fi
 664                         fi
 665
 666                         if [ -n "${offset}" ] && [ 0 -lt "${offset}" ]
 667                         then
 668                                 options="${options} -o ${offset}"
 669                         fi
 670
 671                         if [ -z "${encryption}" ]
 672                         then
 673                                 losetup ${options} "${dev}" "${fspath}"
 674                         else
 675                                 # Loop AES encryption
 676                                 while true
 677                                 do
 678                                         load_keymap
 679
 680                                         echo -n "Enter passphrase for root filesystem: " >&6
 681                                         read -s passphrase
 682                                         echo "${passphrase}" > /tmp/passphrase
 683                                         unset passphrase
 684                                         exec 9</tmp/passphrase
 685                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 686                                         error=${?}
 687                                         exec 9<&-
 688                                         rm -f /tmp/passphrase
 689
 690                                         if [ 0 -eq ${error} ]
 691                                         then
 692                                                 unset error
 693                                                 break
 694                                         fi
 695
 696                                         echo
 697                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 698                                         read answer
 699
 700                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 701                                         then
 702                                                 unset answer
 703                                                 break
 704                                         fi
 705                                 done
 706                         fi
 707
 708                         echo "${dev}"
 709                         return 0
 710                 fi
 711         done
 712
 713         panic "No loop devices available"
 714 }
 715
 716 try_mount ()
 717 {
 718         dev="${1}"
 719         mountp="${2}"
 720         opts="${3}"
 721         fstype="${4}"
 722
 723         old_mountp="$(where_is_mounted ${dev})"
 724
 725         if [ -n "${old_mountp}" ]
 726         then
 727                 if [ "${opts}" != "ro" ]
 728                 then
 729                         mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
 730                 fi
 731
 732                 mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
 733         else
 734                 if [ -z "${fstype}" ]
 735                 then
 736                         fstype=$(get_fstype "${dev}")
 737                 fi
 738                 mount -t "${fstype}" -o "${opts}" "${dev}" "${mountp}" || \
 739                 ( echo "SKIPPING: Cannot mount ${dev} on ${mountp}, fstype=${fstype}, options=${opts}" > live-boot.log && return 0 )
 740         fi
 741 }
 742
 743 mount_persistence_media ()
 744 {
 745         local device=${1}
 746         local probe=${2}
 747
 748         local backing="/live/persistence/$(basename ${device})"
 749
 750         mkdir -p "${backing}"
 751         local old_backing="$(where_is_mounted ${device})"
 752         if [ -z "${old_backing}" ]
 753         then
 754                 local fstype="$(get_fstype ${device})"
 755                 local mount_opts="rw,noatime"
 756                 if [ -n "${PERSISTENCE_READONLY}" ]
 757                 then
 758                         mount_opts="ro,noatime"
 759                 fi
 760                 if mount -t "${fstype}" -o "${mount_opts}" "${device}" "${backing}" >/dev/null
 761                 then
 762                         echo ${backing}
 763                         return 0
 764                 else
 765                         [ -z "${probe}" ] && log_warning_msg "Failed to mount persistence media ${device}"
 766                         rmdir "${backing}"
 767                         return 1
 768                 fi
 769         elif [ "${backing}" != "${old_backing}" ]
 770         then
 771                 if mount --move ${old_backing} ${backing} >/dev/null
 772                 then
 773                         echo ${backing}
 774                         return 0
 775                 else
 776                         [ -z "${probe}" ] && log_warning_msg "Failed to move persistence media ${device}"
 777                         rmdir "${backing}"
 778                         return 1
 779                 fi
 780         fi
 781         return 0
 782 }
 783
 784 close_persistence_media () {
 785         local device=${1}
 786         local backing="$(where_is_mounted ${device})"
 787
 788         if [ -d "${backing}" ]
 789         then
 790                 umount "${backing}" >/dev/null 2>&1
 791                 rmdir "${backing}" >/dev/null 2>&1
 792         fi
 793
 794         if is_active_luks_mapping ${device}
 795         then
 796                 /sbin/cryptsetup luksClose ${device}
 797         fi
 798 }
 799
 800 open_luks_device ()
 801 {
 802         dev="${1}"
 803         name="$(basename ${dev})"
 804         opts="--key-file=-"
 805         if [ -n "${PERSISTENCE_READONLY}" ]
 806         then
 807                 opts="${opts} --readonly"
 808         fi
 809
 810         if /sbin/cryptsetup status "${name}" >/dev/null 2>&1
 811         then
 812                 re="^[[:space:]]*device:[[:space:]]*\([^[:space:]]*\)$"
 813                 opened_dev=$(cryptsetup status ${name} 2>/dev/null | grep "${re}" | sed "s|${re}|\1|")
 814                 if [ "${opened_dev}" = "${dev}" ]
 815                 then
 816                         luks_device="/dev/mapper/${name}"
 817                         echo ${luks_device}
 818                         return 0
 819                 else
 820                         log_warning_msg "Cannot open luks device ${dev} since ${opened_dev} already is opened with its name"
 821                         return 1
 822                 fi
 823         fi
 824
 825         load_keymap
 826
 827         while true
 828         do
 829                 /lib/cryptsetup/askpass "Enter passphrase for ${dev}: " | \
 830                         /sbin/cryptsetup -T 1 luksOpen ${dev} ${name} ${opts}
 831
 832                 if [ 0 -eq ${?} ]
 833                 then
 834                         luks_device="/dev/mapper/${name}"
 835                         echo ${luks_device}
 836                         return 0
 837                 fi
 838
 839                 echo >&6
 840                 echo -n "There was an error decrypting ${dev} ... Retry? [Y/n] " >&6
 841                 read answer
 842
 843                 if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 844                 then
 845                         return 2
 846                 fi
 847         done
 848 }
 849
 850 get_gpt_name ()
 851 {
 852     local dev="${1}"
 853     /sbin/blkid -s PART_ENTRY_NAME -p -o value ${dev} 2>/dev/null
 854 }
 855
 856 is_gpt_device ()
 857 {
 858     local dev="${1}"
 859     [ "$(/sbin/blkid -s PART_ENTRY_SCHEME -p -o value ${dev} 2>/dev/null)" = "gpt" ]
 860 }
 861
 862 probe_for_gpt_name ()
 863 {
 864         local overlays="${1}"
 865         local snapshots="${2}"
 866         local dev="${3}"
 867
 868         local gpt_dev="${dev}"
 869         if is_active_luks_mapping ${dev}
 870         then
 871                 # if $dev is an opened luks device, we need to check
 872                 # GPT stuff on the backing device
 873                 gpt_dev=$(get_luks_backing_device "${dev}")
 874         fi
 875
 876         if ! is_gpt_device ${gpt_dev}
 877         then
 878                 return
 879         fi
 880
 881         local gpt_name=$(get_gpt_name ${gpt_dev})
 882         for label in ${overlays} ${snapshots}
 883         do
 884                 if [ "${gpt_name}" = "${label}" ]
 885                 then
 886                         echo "${label}=${dev}"
 887                 fi
 888         done
 889 }
 890
 891 probe_for_fs_label ()
 892 {
 893         local overlays="${1}"
 894         local snapshots="${2}"
 895         local dev="${3}"
 896
 897         for label in ${overlays} ${snapshots}
 898         do
 899                 if [ "$(/sbin/blkid -s LABEL -o value $dev 2>/dev/null)" = "${label}" ]
 900                 then
 901                         echo "${label}=${dev}"
 902                 fi
 903         done
 904 }
 905
 906 probe_for_file_name ()
 907 {
 908         local overlays="${1}"
 909         local snapshots="${2}"
 910         local dev="${3}"
 911
 912         local ret=""
 913         local backing="$(mount_persistence_media ${dev} probe)"
 914         if [ -z "${backing}" ]
 915         then
 916             return
 917         fi
 918
 919         for label in ${overlays}
 920         do
 921                 path=${backing}/${PERSISTENCE_PATH}${label}
 922                 if [ -f "${path}" ]
 923                 then
 924                         local loopdev=$(setup_loop "${path}" "loop" "/sys/block/loop*")
 925                         ret="${ret} ${label}=${loopdev}"
 926                 fi
 927         done
 928         for label in ${snapshots}
 929         do
 930                 for ext in squashfs cpio.gz ext2 ext3 ext4 jffs2
 931                 do
 932                         path="${PERSISTENCE_PATH}${label}.${ext}"
 933                         if [ -f "${backing}/${path}" ]
 934                         then
 935                                 ret="${ret} ${label}=${dev}:${backing}:${path}"
 936                         fi
 937                 done
 938         done
 939
 940         if [ -n "${ret}" ]
 941         then
 942                 echo ${ret}
 943         else
 944                 umount ${backing} > /dev/null 2>&1 || true
 945         fi
 946 }
 947
 948 find_persistence_media ()
 949 {
 950         # Scans devices for overlays and snapshots, and returns a whitespace
 951         # separated list of how to use them. Only overlays with a partition
 952         # label or file name in ${overlays} are returned, and ditto for
 953         # snapshots with labels in ${snapshots}.
 954         #
 955         # When scanning a LUKS device, the user will be asked to enter the
 956         # passphrase; on failure to enter it, or if no persistence partitions
 957         # or files were found, the LUKS device is closed.
 958         #
 959         # For a snapshot file the return value is ${label}=${snapdata}", where
 960         # ${snapdata} is the parameter used for try_snap().
 961         #
 962         # For all other cases (overlay/snapshot partition and overlay file) the
 963         # return value is "${label}=${device}", where ${device} a device that
 964         # can mount the content. In the case of an overlay file, the device
 965         # containing the file will remain mounted as a side-effect.
 966         #
 967         # No devices in ${black_listed_devices} will be scanned, and if
 968         # ${white_list_devices} is non-empty, only devices in it will be
 969         # scanned.
 970
 971         local overlays="${1}"
 972         local snapshots="${2}"
 973         local white_listed_devices="${3}"
 974         local ret=""
 975
 976         for dev in $(storage_devices "" "${white_listed_devices}")
 977         do
 978                 local result=""
 979
 980                 local luks_device=""
 981                 # Check if it's a luks device; we'll have to open the device
 982                 # in order to probe any filesystem it contains, like we do
 983                 # below. activate_custom_mounts() also depends on that any luks
 984                 # device already has been opened.
 985                 if echo ${PERSISTENCE_ENCRYPTION} | grep -qe "\<luks\>" && \
 986                    is_luks_partition ${dev}
 987                 then
 988                         if luks_device=$(open_luks_device "${dev}")
 989                         then
 990                                 dev="${luks_device}"
 991                         else
 992                                 # skip $dev since we failed/chose not to open it
 993                                 continue
 994                         fi
 995                 elif echo ${PERSISTENCE_ENCRYPTION} | grep -qve "\<none\>"
 996                 then
 997                         # skip $dev since we don't allow unencrypted storage
 998                         continue
 999                 fi
1000
1001                 # Probe for matching GPT partition names or filesystem labels
1002                 if echo ${PERSISTENCE_STORAGE} | grep -qe "\<filesystem\>"
1003                 then
1004                         result=$(probe_for_gpt_name "${overlays}" "${snapshots}" ${dev})
1005                         if [ -n "${result}" ]
1006                         then
1007                                 ret="${ret} ${result}"
1008                                 continue
1009                         fi
1010
1011                         result=$(probe_for_fs_label "${overlays}" "${snapshots}" ${dev})
1012                         if [ -n "${result}" ]
1013                         then
1014                                 ret="${ret} ${result}"
1015                                 continue
1016                         fi
1017                 fi
1018
1019                 # Probe for files with matching name on mounted partition
1020                 if echo ${PERSISTENCE_STORAGE} | grep -qe "\<file\>"
1021                 then
1022                         result=$(probe_for_file_name "${overlays}" "${snapshots}" ${dev})
1023                         if [ -n "${result}" ]
1024                         then
1025                                 ret="${ret} ${result}"
1026                                 continue
1027                         fi
1028                 fi
1029
1030                 # Close luks device if it isn't used
1031                 if [ -z "${result}" ] && [ -n "${luks_device}" ] && \
1032                    is_active_luks_mapping "${luks_device}"
1033                 then
1034                         /sbin/cryptsetup luksClose "${luks_device}"
1035                 fi
1036         done
1037
1038         if [ -n "${ret}" ]
1039         then
1040                 echo ${ret}
1041         fi
1042 }
1043
1044 get_mac ()
1045 {
1046         mac=""
1047
1048         for adaptor in /sys/class/net/*
1049         do
1050                 status="$(cat ${adaptor}/iflink)"
1051
1052                 if [ "${status}" -eq 2 ]
1053                 then
1054                         mac="$(cat ${adaptor}/address)"
1055                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
1056                 fi
1057         done
1058
1059         echo ${mac}
1060 }
1061
1062 is_luks_partition ()
1063 {
1064         device="${1}"
1065         /sbin/cryptsetup isLuks "${device}" 1>/dev/null 2>&1
1066 }
1067
1068 is_active_luks_mapping ()
1069 {
1070         device="${1}"
1071         /sbin/cryptsetup status "${device}" 1>/dev/null 2>&1
1072 }
1073
1074 get_luks_backing_device () {
1075         device=${1}
1076         cryptsetup status ${device} 2> /dev/null | \
1077                 awk '{if ($1 == "device:") print $2}'
1078 }
1079
1080 removable_dev ()
1081 {
1082         output_format="${1}"
1083         want_usb="${2}"
1084         ret=
1085
1086         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
1087         do
1088                 dev_ok=
1089                 if [ "$(cat ${sysblock}/removable)" = "1" ]
1090                 then
1091                         if [ -z "${want_usb}" ]
1092                         then
1093                                 dev_ok="yes"
1094                         else
1095                                 if readlink ${sysblock} | grep -q usb
1096                                 then
1097                                         dev_ok="yes"
1098                                 fi
1099                         fi
1100                 fi
1101
1102                 if [ "${dev_ok}" = "yes" ]
1103                 then
1104                         case "${output_format}" in
1105                                 sys)
1106                                         ret="${ret} ${sysblock}"
1107                                         ;;
1108                                 *)
1109                                         devname=$(sys2dev "${sysblock}")
1110                                         ret="${ret} ${devname}"
1111                                         ;;
1112                         esac
1113                 fi
1114         done
1115
1116         echo "${ret}"
1117 }
1118
1119 removable_usb_dev ()
1120 {
1121         output_format="${1}"
1122
1123         removable_dev "${output_format}" "want_usb"
1124 }
1125
1126 non_removable_dev ()
1127 {
1128         output_format="${1}"
1129         ret=
1130
1131         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -vE "/(loop|ram|dm-|fd)")
1132         do
1133                 if [ "$(cat ${sysblock}/removable)" = "0" ]
1134                 then
1135                         case "${output_format}" in
1136                                 sys)
1137                                         ret="${ret} ${sysblock}"
1138                                         ;;
1139                                 *)
1140                                         devname=$(sys2dev "${sysblock}")
1141                                         ret="${ret} ${devname}"
1142                                         ;;
1143                         esac
1144                 fi
1145         done
1146
1147         echo "${ret}"
1148 }
1149
1150 link_files ()
1151 {
1152         # create source's directory structure in dest, and recursively
1153         # create symlinks in dest to to all files in source. if mask
1154         # is non-empty, remove mask from all source paths when
1155         # creating links (will be necessary if we change root, which
1156         # live-boot normally does (into $rootmnt)).
1157
1158         # remove multiple /:s and ensure ending on /
1159         local src_dir="$(trim_path ${1})/"
1160         local dest_dir="$(trim_path ${2})/"
1161         local src_mask="${3}"
1162
1163         # This check can only trigger on the inital, non-recursive call since
1164         # we create the destination before recursive calls
1165         if [ ! -d "${dest_dir}" ]
1166         then
1167                 log_warning_msg "Must link_files into a directory"
1168                 return
1169         fi
1170
1171         find "${src_dir}" -mindepth 1 -maxdepth 1 | while read src; do
1172                 local dest="${dest_dir}$(basename "${src}")"
1173                 if [ -d "${src}" ]
1174                 then
1175                         if [ -z "$(ls -A "${src}")" ]
1176                         then
1177                                 continue
1178                         fi
1179                         if [ ! -d "${dest}" ]
1180                         then
1181                                 mkdir -p "${dest}"
1182                                 chown_ref "${src}" "${dest}"
1183                                 chmod_ref "${src}" "${dest}"
1184                         fi
1185                         link_files "${src}" "${dest}" "${src_mask}"
1186                 else
1187                         local final_src=${src}
1188                         if [ -n "${src_mask}" ]
1189                         then
1190                                 final_src="$(echo ${final_src} | sed "s|^${src_mask}||")"
1191                         fi
1192                         rm -rf "${dest}" 2> /dev/null
1193                         ln -s "${final_src}" "${dest}"
1194                         chown_ref "${src}" "${dest}"
1195                 fi
1196         done
1197 }
1198
1199 do_union ()
1200 {
1201         local unionmountpoint="${1}"    # directory where the union is mounted
1202         local unionrw="${2}"            # branch where the union changes are stored
1203         local unionro1="${3}"           # first underlying read-only branch (optional)
1204         local unionro2="${4}"           # second underlying read-only branch (optional)
1205
1206         if [ "${UNIONTYPE}" = "aufs" ]
1207         then
1208                 rw_opt="rw"
1209                 ro_opt="rr+wh"
1210                 noxino_opt="noxino"
1211         elif [ "${UNIONTYPE}" = "unionfs-fuse" ]
1212         then
1213                 rw_opt="RW"
1214                 ro_opt="RO"
1215         else
1216                 rw_opt="rw"
1217                 ro_opt="ro"
1218         fi
1219
1220         case "${UNIONTYPE}" in
1221                 unionfs-fuse)
1222                         unionmountopts="-o cow -o noinitgroups -o default_permissions -o allow_other -o use_ino -o suid"
1223                         unionmountopts="${unionmountopts} ${unionrw}=${rw_opt}"
1224                         if [ -n "${unionro1}" ]
1225                         then
1226                                 unionmountopts="${unionmountopts}:${unionro1}=${ro_opt}"
1227                         fi
1228                         if [ -n "${unionro2}" ]
1229                         then
1230                                 unionmountopts="${unionmountopts}:${unionro2}=${ro_opt}"
1231                         fi
1232                         ( sysctl -w fs.file-max=391524 ; ulimit -HSn 16384
1233                         unionfs-fuse ${unionmountopts} "${unionmountpoint}" ) && \
1234                         ( mkdir -p /run/sendsigs.omit.d
1235                         pidof unionfs-fuse >> /run/sendsigs.omit.d/unionfs-fuse || true )
1236                         ;;
1237
1238                 overlayfs)
1239                         # XXX: can unionro2 be used? (overlayfs only handles two dirs, but perhaps they can be chained?)
1240                         # XXX: and can unionro1 be optional? i.e. can overlayfs skip lowerdir?
1241                         unionmountopts="-o noatime,lowerdir=${unionro1},upperdir=${unionrw}"
1242                         mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
1243                         ;;
1244
1245                 *)
1246                         unionmountopts="-o noatime,${noxino_opt},dirs=${unionrw}=${rw_opt}"
1247                         if [ -n "${unionro1}" ]
1248                         then
1249                                 unionmountopts="${unionmountopts}:${unionro1}=${ro_opt}"
1250                         fi
1251                         if [ -n "${unionro2}" ]
1252                         then
1253                                 unionmountopts="${unionmountopts}:${unionro2}=${ro_opt}"
1254                         fi
1255                         mount -t ${UNIONTYPE} ${unionmountopts} ${UNIONTYPE} "${unionmountpoint}"
1256                         ;;
1257         esac
1258 }
1259
1260 get_custom_mounts ()
1261 {
1262         # Side-effect: leaves $devices with live-persistence.conf mounted in /live/persistence
1263         # Side-effect: prints info to file $custom_mounts
1264
1265         local custom_mounts=${1}
1266         shift
1267         local devices=${@}
1268
1269         local bindings="/tmp/bindings.list"
1270         local links="/tmp/links.list"
1271         rm -rf ${bindings} ${links} 2> /dev/null
1272
1273         for device in ${devices}
1274         do
1275                 if [ ! -b "${device}" ]
1276                 then
1277                         continue
1278                 fi
1279
1280                 local device_name="$(basename ${device})"
1281                 local backing=$(mount_persistence_media ${device})
1282                 if [ -z "${backing}" ]
1283                 then
1284                         continue
1285                 fi
1286
1287                 local include_list="${backing}/${persistence_list}"
1288                 if [ ! -r "${include_list}" ]
1289                 then
1290                         continue
1291                 fi
1292
1293                 if [ -n "${DEBUG}" ] && [ -e "${include_list}" ]
1294                 then
1295                         cp ${include_list} /live/persistence/${persistence_list}.${device_name}
1296                 fi
1297
1298                 while read dir options # < ${include_list}
1299                 do
1300                         if echo ${dir} | grep -qe "^[[:space:]]*\(#.*\)\?$"
1301                         then
1302                                 # skipping empty or commented lines
1303                                 continue
1304                         fi
1305
1306                         if trim_path ${dir} | grep -q -e "^[^/]" -e "^/live\(/.*\)\?$" -e "^/\(.*/\)\?\.\.\?\(/.*\)\?$"
1307                         then
1308                                 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."
1309                                 continue
1310                         fi
1311
1312                         local opt_source=""
1313                         local opt_link=""
1314                         for opt in $(echo ${options} | tr ',' ' ');
1315                         do
1316                                 case "${opt}" in
1317                                         source=*)
1318                                                 opt_source=${opt#source=}
1319                                                 ;;
1320                                         link)
1321                                                 opt_link="yes"
1322                                                 ;;
1323                                         union|bind)
1324                                                 ;;
1325                                         *)
1326                                                 log_warning_msg "Skipping custom mount with unkown option: ${opt}"
1327                                                 continue 2
1328                                                 ;;
1329                                 esac
1330                         done
1331
1332                         local source="${dir}"
1333                         if [ -n "${opt_source}" ]
1334                         then
1335                                 if echo ${opt_source} | grep -q -e "^/" -e "^\(.*/\)\?\.\.\?\(/.*\)\?$" && [ "${source}" != "." ]
1336                                 then
1337                                         log_warning_msg "Skipping unsafe custom mount with option source=${opt_source}: must be either \".\" (the media root) or a relative path w.r.t. the media root that contains neither comas, nor the special \".\" and \"..\" path components"
1338                                         continue
1339                                 else
1340                                         source="${opt_source}"
1341                                 fi
1342                         fi
1343
1344                         local full_source="$(trim_path ${backing}/${source})"
1345                         local full_dest="$(trim_path ${rootmnt}/${dir})"
1346                         if [ -n "${opt_link}" ]
1347                         then
1348                                 echo "${device} ${full_source} ${full_dest} ${options}" >> ${links}
1349                         else
1350                                 echo "${device} ${full_source} ${full_dest} ${options}" >> ${bindings}
1351                         fi
1352                 done < ${include_list}
1353         done
1354
1355         # We sort the list according to destination so we're sure that
1356         # we won't hide a previous mount. We also ignore duplicate
1357         # destinations in a more or less arbitrary way.
1358         [ -e "${bindings}" ] && sort -k3 -sbu ${bindings} >> ${custom_mounts} && rm ${bindings}
1359
1360         # After all mounts are considered we add symlinks so they
1361         # won't be hidden by some mount.
1362         [ -e "${links}" ] && cat ${links} >> ${custom_mounts} && rm ${links}
1363
1364         # We need to make sure that no two custom mounts have the same sources
1365         # or are nested; if that is the case, too much weird stuff can happen.
1366         local prev_source="impossible source" # first iteration must not match
1367         local prev_dest=""
1368         # This sort will ensure that a source /a comes right before a source
1369         # /a/b so we only need to look at the previous source
1370         sort -k2 -b ${custom_mounts} |
1371         while read device source dest options
1372         do
1373                 if echo ${source} | grep -qe "^${prev_source}\(/.*\)\?$"
1374                 then
1375                         panic "Two persistence mounts have the same or nested sources: ${source} on ${dest}, and ${prev_source} on ${prev_dest}"
1376                 fi
1377                 prev_source=${source}
1378                 prev_dest=${dest}
1379         done
1380 }
1381
1382 activate_custom_mounts ()
1383 {
1384         local custom_mounts="${1}" # the ouput from get_custom_mounts()
1385         local used_devices=""
1386
1387         while read device source dest options # < ${custom_mounts}
1388         do
1389                 local opt_bind="yes"
1390                 local opt_link=""
1391                 local opt_union=""
1392                 for opt in $(echo ${options} | tr ',' ' ');
1393                 do
1394                         case "${opt}" in
1395                                 bind)
1396                                         opt_bind="yes"
1397                                         unset opt_link opt_union
1398                                         ;;
1399                                 link)
1400                                         opt_link="yes"
1401                                         unset opt_bind opt_union
1402                                         ;;
1403                                 union)
1404                                         opt_union="yes"
1405                                         unset opt_bind opt_link
1406                                         ;;
1407                         esac
1408                 done
1409
1410                 if [ -n "$(what_is_mounted_on "${dest}")" ]
1411                 then
1412                         if [ "${dest}" = "${rootmnt}" ]
1413                         then
1414                                 umount "${dest}"
1415                         else
1416                                 log_warning_msg "Skipping custom mount ${dest}: $(what_is_mounted_on "${dest}") is already mounted there"
1417                                 continue
1418                         fi
1419                 fi
1420
1421                 if [ ! -d "${dest}" ]
1422                 then
1423                         # create the destination and delete existing files in
1424                         # its path that are in the way
1425                         path="/"
1426                         for dir in $(echo ${dest} | sed -e 's|/\+| |g')
1427                         do
1428                                 path=$(trim_path ${path}/${dir})
1429                                 if [ -f ${path} ]
1430                                 then
1431                                         rm -f ${path}
1432                                 fi
1433                                 if [ ! -e ${path} ]
1434                                 then
1435                                         mkdir -p ${path}
1436                                         if echo ${path} | grep -qe "^${rootmnt}/*home/[^/]\+"
1437                                         then
1438                                                 # if ${dest} is in /home try fixing proper ownership by assuming that the intended user is the first, which is usually the case
1439                                                 # FIXME: this should really be handled by live-config since we don't know for sure which uid a certain user has until then
1440                                                 chown 1000:1000 ${path}
1441                                         fi
1442                                 fi
1443                         done
1444                 fi
1445
1446                 # if ${source} doesn't exist on our persistence media
1447                 # we bootstrap it with $dest from the live filesystem.
1448                 # this both makes sense and is critical if we're
1449                 # dealing with /etc or other system dir.
1450                 if [ ! -d "${source}" ]
1451                 then
1452                         if [ -n "${PERSISTENCE_READONLY}" ]
1453                         then
1454                                 continue
1455                         elif [ -n "${opt_union}" ] || [ -n "${opt_link}" ]
1456                         then
1457                                 # unions and don't need to be bootstrapped
1458                                 # link dirs can't be bootstrapped in a sensible way
1459                                 mkdir -p "${source}"
1460                                 chown_ref "${dest}" "${source}"
1461                                 chmod_ref "${dest}" "${source}"
1462                         elif [ -n "${opt_bind}" ]
1463                         then
1464                                 # ensure that $dest is not copied *into* $source
1465                                 mkdir -p "$(dirname ${source})"
1466                                 cp -a "${dest}" "${source}"
1467                         fi
1468                 fi
1469
1470                 # XXX: If CONFIG_AUFS_ROBR is added to the Debian kernel we can
1471                 # ignore the loop below and set rofs_dest_backing=$dest
1472                 local rofs_dest_backing=""
1473                 if [ -n "${opt_link}"]
1474                 then
1475                         for d in /live/rofs/*
1476                         do
1477                                 if [ -n "${rootmnt}" ]
1478                                 then
1479                                         rofs_dest_backing="${d}/$(echo ${dest} | sed -e "s|${rootmnt}||")"
1480                                 else
1481                                         rofs_dest_backing="${d}/${dest}"
1482                                 fi
1483                                 if [ -d "${rofs_dest_backing}" ]
1484                                 then
1485                                         break
1486                                 else
1487                                         rofs_dest_backing=""
1488                                 fi
1489                         done
1490                 fi
1491
1492                 if [ -n "${opt_link}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1493                 then
1494                         link_files ${source} ${dest} ${rootmnt}
1495                 elif [ -n "${opt_link}" ] && [ -n "${PERSISTENCE_READONLY}" ]
1496                 then
1497                         mkdir -p /live/persistence
1498                         local links_source=$(mktemp -d /live/persistence/links-source-XXXXXX)
1499                         chown_ref ${source} ${links_source}
1500                         chmod_ref ${source} ${links_source}
1501                         # We put the cow dir in the below strange place to
1502                         # make it absolutely certain that the link source
1503                         # has its own directory and isn't nested with some
1504                         # other custom mount (if so that mount's files would
1505                         # be linked, causing breakage.
1506                         local cow_dir="/live/overlay/live/persistence/$(basename ${links_source})"
1507                         mkdir -p ${cow_dir}
1508                         chown_ref "${source}" "${cow_dir}"
1509                         chmod_ref "${source}" "${cow_dir}"
1510                         do_union ${links_source} ${cow_dir} ${source} ${rofs_dest_backing}
1511                         link_files ${links_source} ${dest} ${rootmnt}
1512                 elif [ -n "${opt_union}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1513                 then
1514                         do_union ${dest} ${source} ${rofs_dest_backing}
1515                 elif [ -n "${opt_bind}" ] && [ -z "${PERSISTENCE_READONLY}" ]
1516                 then
1517                         mount --bind "${source}" "${dest}"
1518                 elif [ -n "${opt_bind}" -o -n "${opt_union}" ] && [ -n "${PERSISTENCE_READONLY}" ]
1519                 then
1520                         # bind-mount and union mount are handled the same
1521                         # in read-only mode, but note that rofs_dest_backing
1522                         # is non-empty (and necessary) only for unions
1523                         if [ -n "${rootmnt}" ]
1524                         then
1525                                 local cow_dir="$(echo ${dest} | sed -e "s|^${rootmnt}|/live/overlay/|")"
1526                         else
1527                                 # This is happens if persistence is activated
1528                                 # post boot
1529                                 local cow_dir="/live/overlay/${dest}"
1530                         fi
1531                         if [ -e "${cow_dir}" ] && [ -z "${opt_link}" ]
1532                         then
1533                                 # If an earlier custom mount has files here
1534                                 # it will "block" the current mount's files
1535                                 # which is undesirable
1536                                 rm -rf "${cow_dir}"
1537                         fi
1538                         mkdir -p ${cow_dir}
1539                         chown_ref "${source}" "${cow_dir}"
1540                         chmod_ref "${source}" "${cow_dir}"
1541                         do_union ${dest} ${cow_dir} ${source} ${rofs_dest_backing}
1542                 fi
1543
1544                 PERSISTENCE_IS_ON="1"
1545                 export PERSISTENCE_IS_ON
1546
1547                 if echo ${used_devices} | grep -qve "^\(.* \)\?${device}\( .*\)\?$"
1548                 then
1549                         used_devices="${used_devices} ${device}"
1550                 fi
1551         done < ${custom_mounts}
1552
1553         echo ${used_devices}
1554 }
1555
1556 fix_backwards_compatibility ()
1557 {
1558         local device=${1}
1559         local dir=${2}
1560         local opt=${3}
1561
1562         if [ -n "${PERSISTENCE_READONLY}" ]
1563         then
1564                 return
1565         fi
1566
1567         local backing="$(mount_persistence_media ${device})"
1568         if [ -z "${backing}" ]
1569         then
1570                 return
1571         fi
1572
1573         local include_list="${backing}/${persistence_list}"
1574         if [ ! -r "${include_list}" ]
1575         then
1576                 echo "# persistence backwards compatibility:
1577 ${dir} ${opt},source=." > "${include_list}"
1578         fi
1579 }
1580
1581 is_mountpoint ()
1582 {
1583         directory="$1"
1584
1585         [ $(stat -fc%d:%D "${directory}") != $(stat -fc%d:%D "${directory}/..") ]
1586 }