scripts/casper

   1 #!/bin/sh
   2
   3 # set -e
   4
   5 export PATH=/root/usr/bin:/root/usr/sbin:/root/bin:/root/sbin:/usr/bin:/usr/sbin:/bin:/sbin
   6
   7 mountpoint=/live_media
   8
   9 root_persistence="casper-rw"
  10 home_persistence="home-rw"
  11
  12 USERNAME="casper"
  13 USERFULLNAME="Live session user"
  14 HOST="live"
  15 BUILD_SYSTEM="Debian"
  16
  17 mkdir -p $mountpoint
  18
  19 [ -f /etc/casper.conf ] && . /etc/casper.conf
  20
  21 export USERNAME USERFULLNAME HOST BUILD_SYSTEM
  22
  23 if [ "${BUILD_SYSTEM}" == "Ubuntu" ]; then
  24     MP_QUIET="-Q"
  25 else
  26     MP_QUIET="-q"
  27 fi
  28
  29 # looking for casper specifics options as kernel parameters
  30 for x in $(cat /proc/cmdline); do
  31     case $x in
  32         userfullname*)
  33             export USERFULLNAME=${x#userfullname=}
  34             export CASPERCONF="changed"
  35             ;;
  36         host*)
  37             export HOST=${x#host=}
  38             export CASPERCONF="changed"
  39             ;;
  40         username*)
  41             export USERNAME=${x#username=}
  42             export CASPERCONF="changed"
  43             ;;
  44         netboot*)
  45             export NETBOOT=${x#netboot=} ;;
  46         toram)
  47             export TORAM=1 ;;
  48         hide-cow)
  49             export HIDECOW=1 ;;
  50         persistent)
  51             export PERSISTENT=1 ;;
  52         staticip*)
  53             STATICIP=${x#staticip=}
  54             if [ "${STATICIP}" == "" ]; then
  55                 STATICIP="frommedia"
  56             fi
  57             export STATICIP ;;
  58         casper-getty)
  59             export CASPERGETTY=1 ;;
  60     esac
  61 done
  62
  63 # sort of compatibility with netboot.h from linux docs
  64 if [ -z "${NETBOOT}" ]; then
  65     if [ "${ROOT}" == "/dev/nfs" ]; then
  66         NETBOOT="nfs"
  67         export NETBOOT
  68     elif [ "${ROOT}" == "/dev/cifs" ]; then
  69         NETBOOT="cifs"
  70         export NETBOOT
  71     fi
  72 fi
  73
  74 is_casper_path() {
  75     path=$1
  76     if [ -d "$path/casper" ]; then
  77         if [ "$(echo $path/casper/*.cloop)" != "$path/casper/*.cloop" ] ||
  78             [ "$(echo $path/casper/*.squashfs)" != "$path/casper/*.squashfs" ] ||
  79             [ "$(echo $path/casper/*.ext2)" != "$path/casper/*.ext2" ] ||
  80             [ "$(echo $path/casper/*.dir)" != "$path/casper/*.dir" ]; then
  81             return 0
  82         fi
  83     fi
  84     return 1
  85 }
  86
  87 subdevices() {
  88     sysblock=$1
  89     r=""
  90     for dev in "${sysblock}" "${sysblock}"/*; do
  91         if [ -e "${dev}/dev" ]; then
  92             r="${r} ${dev}"
  93         fi
  94     done
  95     echo ${r}
  96 }
  97
  98 get_backing_device() {
  99     case "$1" in
 100         *.cloop)
 101             echo $(setup_loop "$1" "cloop" "/sys/block/cloop*")
 102             ;;
 103         *.squashfs|*.ext2)
 104             echo $(setup_loop "$1" "loop" "/sys/block/loop*")
 105             ;;
 106         *.dir)
 107             echo "directory"
 108             ;;
 109         *)
 110             panic "Unrecognized casper filesystem: $1"
 111             ;;
 112     esac
 113 }
 114
 115 match_files_in_dir() {
 116     # Does any files match pattern $1 ?
 117
 118     local pattern="$1"
 119     if [ "$(echo $pattern)" != "$pattern" ]; then
 120         return 0
 121     fi
 122     return 1
 123 }
 124
 125 mount_images_in_directory() {
 126     directory="$1"
 127     rootmnt="$2"
 128     if match_files_in_dir "$directory/casper/*.cloop"; then
 129         # Let's hope there's just one matching *.cloop... FIXME
 130         setup_devmapper $(get_backing_device "$directory/casper/*.cloop") "$rootmnt"
 131     elif match_files_in_dir "$directory/casper/*.squashfs" ||
 132         match_files_in_dir "$directory/casper/*.ext2" ||
 133         match_files_in_dir "$directory/casper/*.dir"; then
 134         setup_unionfs "$directory/casper" "$rootmnt"
 135     else
 136         :
 137     fi
 138 }
 139
 140 sys2dev() {
 141     sysdev=${1#/sys}
 142     echo "/dev/$(udevinfo -q name -p ${sysdev} 2>/dev/null|| echo ${sysdev##*/})"
 143 }
 144
 145 setup_loop() {
 146     local fspath=$1
 147     local module=$2
 148     local pattern=$3
 149
 150     modprobe "${MP_QUIET}" -b "$module"
 151     udevsettle
 152
 153     for loopdev in $pattern; do
 154         if [ "$(cat $loopdev/size)" -eq 0 ]; then
 155             dev=$(sys2dev "${loopdev}")
 156             losetup "$dev" "$fspath"
 157             echo "$dev"
 158             return 0
 159         fi
 160     done
 161     panic "No loop devices available"
 162 }
 163
 164 get_fstype() {
 165     local FSTYPE
 166     local FSSIZE
 167     eval $(fstype < $1)
 168     if [ "$FSTYPE" != "unknown" ]; then
 169         echo $FSTYPE
 170         return 0
 171     fi
 172     /lib/udev/vol_id -t $1 2>/dev/null
 173 }
 174
 175 setup_devmapper() {
 176     backdev="$1"
 177     rootmnt="$2"
 178
 179     modprobe "${MP_QUIET}" -b dm-mod
 180     COW_DEVICE=/dev/ram1
 181     COW_NAME="casper-cow"
 182
 183     BACKING_FILE_SIZE=$(blockdev --getsize "$backdev")
 184     MAX_COW_SIZE=$(blockdev --getsize "$COW_DEVICE")
 185     CHUNK_SIZE=8 # sectors
 186
 187     if [ -z "$COW_SIZE" -o "$COW_SIZE" -gt "$MAX_COW_SIZE" ]; then
 188         COW_SIZE=$MAX_COW_SIZE
 189     fi
 190
 191     echo "0 $COW_SIZE linear $COW_DEVICE 0" | dmsetup create $COW_NAME
 192
 193     echo "0 $BACKING_FILE_SIZE snapshot $backdev /dev/mapper/$COW_NAME p $CHUNK_SIZE" | \
 194         dmsetup create casper-snapshot
 195     if [ "$(get_fstype $backdev)" = "unknown" ]; then
 196         panic "Unknown file system type on $backdev"
 197     fi
 198     mount -t $(get_fstype "$backdev") /dev/mapper/casper-snapshot $rootmnt || panic "Can not mount /dev/mapper/casper/snapshot on $rootmnt"
 199
 200     mkdir -p "$rootmnt/rofs"
 201     echo "0 $BACKING_FILE_SIZE linear $backdev 0" | dmsetup create casper-backing
 202     mount -t $(get_fstype "$backdev") /dev/mapper/casper-backing "$rootmnt/rofs"
 203 }
 204
 205 where_is_mounted() {
 206     device=$1
 207     if grep -q "^$device " /proc/mounts; then
 208         grep "^$device " /proc/mounts | read d mountpoint rest
 209         echo $mountpoint
 210         return 0
 211     fi
 212     return 1
 213 }
 214
 215 copy_to_ram() {
 216     copyfrom="$1"
 217
 218     if [ ! -z "${2}" ] ; then
 219         # This will enable future rampersistence, todo yet
 220         copyto="${2}"
 221         moveit="False"
 222     else
 223         copyto="${copyfrom}_swap"
 224         moveit="True"
 225     fi
 226
 227     size=$(du -ks ${copyfrom} | cut -f1)
 228     size=$(expr ${size} + ${size}/20 ) # Fixme: 5% more to be sure
 229     needed_space=$(expr ${size} * 1024)
 230     freespace=$( expr $(awk '/MemFree/{print $2}' /proc/meminfo) + $( cat /proc/meminfo | grep Cached | head -n 1 | awk '/Cached/{print $2}' - ))
 231
 232     if [ ! ${freespace} -lt ${needed_space}  ] ; then
 233         [ "$quiet" != "y" ] && log_begin_msg "Not enough free memory to copy to ram"
 234         [ "$quiet" != "y" ] && log_end_msg
 235         return
 236     else
 237         [ "$quiet" != "y" ] && log_begin_msg "Copying live media to ram..."
 238         mkdir "${copyto}"
 239         mount -t tmpfs -o size=${size}k /dev/shm ${copyto}
 240         cp -a ${copyfrom}/* ${copyto} # "cp -a" from busybox also copies hidden files
 241         umount ${copyfrom}
 242         if [ "${moveit}" == "True" ]; then
 243             mount -r -o move ${copyto} ${copyfrom}
 244             rmdir ${copyto}
 245         fi
 246         [ "$quiet" != "y" ] && log_end_msg
 247     fi
 248 }
 249
 250 find_cow_device() {
 251     pers_label="${1}"
 252     cow_backing="/${pers_label}-backing"
 253     for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop); do
 254         for dev in $(subdevices "${sysblock}"); do
 255             devname=$(sys2dev "${dev}")
 256             if [ "$(/lib/udev/vol_id -l $devname 2>/dev/null)" = "${pers_label}" ]; then
 257                 echo "$devname"
 258                 return
 259             elif [ "$(get_fstype ${devname})" = "vfat" ]; then
 260                 mkdir -p "${cow_backing}"
 261                 if where_is_mounted ${devname} > /dev/null; then
 262                     mount -o remount,rw ${devname} $(where_is_mounted ${devname}) || panic "Remounting failed"
 263                     mount -o bind $(where_is_mounted ${devname}) ${cow_backing} || panic "Cannot bind-mount"
 264                 else
 265                     mount -t $(get_fstype "${devname}") -o rw "${devname}" ${cow_backing} || panic "Cannot mount $devname on /cow-backing"
 266                 fi
 267
 268                 if [ -e "${cow_backing}/${pers_label}" ]; then
 269                     echo $(setup_loop "${cow_backing}/${pers_label}" "loop" "/sys/block/loop*")
 270                     return 0
 271                 else
 272                     umount ${cow_backing}
 273                 fi
 274             fi
 275         done
 276     done
 277 }
 278
 279 do_netmount() {
 280     rc=1
 281
 282     modprobe "${MP_QUIET}" af_packet # For DHCP
 283
 284     ipconfig ${DEVICE} /tmp/net-${DEVICE}.conf
 285
 286     if [ "${NFSROOT}" = "auto" ]; then
 287         NFSROOT=${ROOTSERVER}:${ROOTPATH}
 288     fi
 289
 290     [ "$quiet" != "y" ] && log_begin_msg "Trying netboot from ${NFSROOT}"
 291
 292     if [ "${NETBOOT}" != "nfs" ] && do_cifsmount ; then
 293         rc=0
 294     elif do_nfsmount ; then
 295         NETBOOT="nfs"
 296         export NETBOOT
 297         rc=0
 298     fi
 299
 300     [ "$quiet" != "y" ] && log_end_msg
 301     return ${rc}
 302 }
 303
 304 do_nfsmount() {
 305     rc=1
 306     modprobe "${MP_QUIET}" nfs
 307     if [ -z "${NFSOPTS}" ]; then
 308         NFSOPTS=""
 309     fi
 310
 311     [ "$quiet" != "y" ] && log_begin_msg "Trying nfsmount -o nolock -o ro ${NFSOPTS} ${NFSROOT} ${mountpoint}"
 312     # FIXME: This for loop is an ugly HACK round an nfs bug
 313     for i in 0 1 2 3 4 5 6 7 8 9 a b c d e f 10 11 12 13; do
 314         nfsmount -o nolock -o ro ${NFSOPTS} "${NFSROOT}" "${mountpoint}" && rc=0 && break
 315         sleep 1
 316     done
 317     return ${rc}
 318 }
 319
 320 do_cifsmount() {
 321     rc=1
 322     if [ -x "/sbin/mount.cifs" ]; then
 323         if [ -z "${NFSOPTS}" ]; then
 324             CIFSOPTS="-ouser=root,password="
 325         else
 326             CIFSOPTS="${NFSOPTS}"
 327         fi
 328
 329         [ "$quiet" != "y" ] && log_begin_msg "Trying mount.cifs ${NFSROOT} ${mountpoint} ${CIFSOPTS}"
 330         modprobe "${MP_QUIET}" cifs
 331
 332         if mount.cifs "${NFSROOT}" "${mountpoint}" "${CIFSOPTS}" ; then
 333             rc=0
 334         fi
 335     fi
 336     return ${rc}
 337 }
 338
 339 setup_unionfs() {
 340     image_directory="$1"
 341     rootmnt="$2"
 342
 343     modprobe "${MP_QUIET}" -b unionfs
 344
 345     # run-init can't deal with this, but we're going to move all of these
 346     # away before it runs anyway.
 347     croot="/casper"
 348
 349     # Let's just mount the read-only file systems first
 350     rofsstring=""
 351     rofslist=""
 352     if [ "${NETBOOT}" == "nfs" ] ; then
 353         roopt="nfsro" # go aroung a bug in nfs-unionfs locking
 354     else
 355         roopt="ro"
 356     fi
 357
 358     mkdir -p "${croot}"
 359     for image_type in "ext2" "squashfs" "dir" ; do
 360         for image in "${image_directory}"/*."${image_type}"; do
 361             imagename=$(basename "${image}")
 362             if [ -d "${image}" ]; then
 363                 # it is a plain directory: do nothing
 364                 rofsstring="${image}=${roopt}:${rofsstring}"
 365                 rofslist="${image} ${rofslist}"
 366             elif [ -f "${image}" ]; then
 367                 backdev=$(get_backing_device "$image")
 368                 fstype=$(get_fstype "${backdev}")
 369                 if [ "${fstype}" = "unknown" ]; then
 370                     panic "Unknown file system type on ${backdev} (${image})"
 371                 fi
 372                 mkdir -p "${croot}/${imagename}"
 373                 mount -t "${fstype}" -o ro "${backdev}" "${croot}/${imagename}" || panic "Can not mount $backdev ($image) on ${croot}/${imagename}" && rofsstring="${croot}/${imagename}=${roopt}:${rofsstring}" && rofslist="${croot}/${imagename} ${rofslist}"
 374             fi
 375         done
 376     done
 377     rofsstring=${rofsstring%:}
 378
 379     mkdir -p /cow
 380     cowdevice="tmpfs"
 381     cow_fstype="tmpfs"
 382
 383     # Looking for "${root_persistence}" device or file
 384     if [ ! -z "${PERSISTENT}" ]; then
 385         cowprobe=$(find_cow_device "${root_persistence}")
 386         if [ -b "${cowprobe}" ]; then
 387             cowdevice=${cowprobe}
 388             cow_fstype=$(get_fstype "${cowprobe}")
 389         else
 390             [ "$quiet" != "y" ] && log_begin_msg "Unable to find the persistent medium"
 391         fi
 392     fi
 393
 394     mount ${cowdevice} -t ${cow_fstype} -o rw /cow || panic "Can not mount $cowdevice on /cow"
 395
 396     # Look for a snapshot to copy
 397
 398
 399     mount -t unionfs -o dirs=/cow=rw:$rofsstring unionfs "$rootmnt" || panic "Unionfs mount failed"
 400
 401     for d in ${rofslist}; do
 402         mkdir -p "${rootmnt}/casper/${d##*/}"
 403         case d in
 404             *.dir) # do nothing # mount -o bind "${d}" "${rootmnt}/casper/${d##*/}"
 405                 ;;
 406             *) mount -o move "${d}" "${rootmnt}/casper/${d##*/}"
 407                 ;;
 408         esac
 409     done
 410
 411     # Adding other custom mounts
 412     if [ ! -z "${PERSISTENT}" ]; then
 413         homecow=$(find_cow_device "${home_persistence}" )
 414         if [ -b "${homecow}" ]; then
 415             mount ${homecow} -t $(get_fstype "${homecow}") -o rw "${rootmnt}/home"
 416         else
 417             [ "$quiet" != "y" ] &&  log_begin_msg "Unable to find the persistent home medium"
 418         fi
 419     fi
 420
 421     if [ -z "${HIDECOW}" ]; then
 422         mkdir -p "$rootmnt/cow"
 423         mount -o bind /cow "$rootmnt/cow"
 424     fi
 425 }
 426
 427 is_usb_device() {
 428     sysfs_path="${1#/sys}"
 429     if /lib/udev/path_id "${sysfs_path}" | grep -E -q "ID_PATH=(usb|pci-[^-]*-usb)"; then
 430         return 0
 431     fi
 432     return 1
 433 }
 434
 435 find_livefs() {
 436     mounted=
 437     for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram); do
 438         devname=$(sys2dev "${sysblock}")
 439         fstype=$(get_fstype "${devname}")
 440         if /lib/udev/cdrom_id ${devname} > /dev/null; then
 441             mount -t ${fstype} -o ro "$devname" $mountpoint || continue
 442             if is_casper_path $mountpoint; then
 443                 echo $mountpoint
 444                 return
 445             else
 446                 umount $mountpoint
 447             fi
 448         elif is_usb_device "$sysblock"; then
 449             for dev in $(subdevices "${sysblock}"); do
 450                 devname=$(sys2dev "${dev}")
 451                 fstype=$(get_fstype "${devname}")
 452                 case ${fstype} in
 453                     vfat|iso9660|udf)
 454                         mount -t ${fstype} -o ro "${devname}" $mountpoint || continue
 455                         if is_casper_path $mountpoint; then
 456                             echo $mountpoint
 457                             return
 458                         else
 459                             umount $mountpoint
 460                         fi
 461                         ;;
 462                 esac
 463             done
 464         elif [ "${fstype}" = "squashfs" ||  \
 465                 "${fstype}" = "ext2" ]; then
 466
 467             # This is an ugly hack situation, the block device has
 468             # an image directly on it.  It's hopefully
 469             # casper, so take it and run with it.
 470
 471             ln -s "${devname}" "${devname}.${fstype}"
 472             echo "${devname}.${fstype}"
 473             return
 474         fi
 475     done
 476 }
 477
 478 set_usplash_timeout() {
 479     if [ -x /sbin/usplash_write ]; then
 480         /sbin/usplash_write "TIMEOUT 120"
 481     fi
 482 }
 483
 484 mountroot() {
 485     exec 6>&1
 486     exec 7>&2
 487     exec > casper.log
 488     exec 2>&1
 489
 490     set_usplash_timeout
 491     [ "$quiet" != "y" ] && log_begin_msg "Running /scripts/casper-premount"
 492     run_scripts /scripts/casper-premount
 493     [ "$quiet" != "y" ] && log_end_msg
 494
 495     # Needed here too because some things (*cough* udev *cough*)
 496     # changes the timeout
 497
 498     set_usplash_timeout
 499
 500     if [ ! -z "${NETBOOT}" ]; then
 501         if do_netmount ; then
 502             livefs_root="${mountpoint}"
 503         else
 504             panic "Unable to find a the network rootfs live file system"
 505         fi
 506     else
 507         # Scan local devices for the image
 508         for i in 0 1 2 3 4 5 6 7 8 9 a b c d e f 10 11 12 13; do
 509             livefs_root=$(find_livefs)
 510             if [ "${livefs_root}" ]; then
 511                 break
 512             fi
 513         done
 514
 515         if [ "$?" -gt 0 ]; then
 516             panic "Unable to find a medium containing a live file system"
 517         fi
 518
 519         if [ ! -z "${TORAM}" ]; then
 520             copy_to_ram "${livefs_root}"
 521         fi
 522     fi
 523     sleep 1
 524
 525     mount_images_in_directory "$livefs_root" "$rootmnt"
 526
 527     log_end_msg
 528
 529     maybe_break casper-bottom
 530     [ "$quiet" != "y" ] && log_begin_msg "Running /scripts/casper-bottom"
 531
 532     run_scripts /scripts/casper-bottom
 533     [ "$quiet" != "y" ] && log_end_msg
 534
 535     exec 1>&6 6>&-
 536     exec 2>&7 7>&-
 537     cp casper.log "${rootmnt}/var/log/"
 538 }