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 ${r}
  38 }
  39
  40 is_supported_fs ()
  41 {
  42         fstype="${1}"
  43
  44         # Validate input first
  45         if [ -z "${fstype}" ]
  46         then
  47                 return 1
  48         fi
  49
  50         # Try to look if it is already supported by the kernel
  51         if grep -q ${fstype} /proc/filesystems
  52         then
  53                 return 0
  54         else
  55                 # Then try to add support for it the gentle way using the initramfs capabilities
  56                 modprobe ${fstype}
  57                 if grep -q ${fstype} /proc/filesystems
  58                 then
  59                         return 0
  60                 # Then try the hard way if /root is already reachable
  61                 else
  62                         kmodule="/root/lib/modules/`uname -r`/${fstype}/${fstype}.ko"
  63                         if [ -e "${kmodule}" ]
  64                         then
  65                                 insmod "${kmodule}"
  66                                 if grep -q ${fstype} /proc/filesystems
  67                                 then
  68                                         return 0
  69                                 fi
  70                         fi
  71                 fi
  72         fi
  73
  74         return 1
  75 }
  76
  77 get_fstype ()
  78 {
  79         # udev (>= 146) no longer provides vol_id
  80         if [ -x /lib/udev/vol_id ]
  81         then
  82                 # lenny
  83                 /lib/udev/vol_id -t ${1} 2>/dev/null
  84         else
  85                 # squeeze
  86                 /sbin/blkid -s TYPE -o value $1 2>/dev/null
  87         fi
  88 }
  89
  90 where_is_mounted ()
  91 {
  92         device=${1}
  93
  94         if grep -q "^${device} " /proc/mounts
  95         then
  96                 # return the first found
  97                 grep -m1 "^${device} " /proc/mounts | cut -f2 -d ' '
  98         fi
  99 }
 100
 101 lastline ()
 102 {
 103         while read lines
 104         do
 105                 line=${lines}
 106         done
 107
 108         echo "${line}"
 109 }
 110
 111 base_path ()
 112 {
 113         testpath="${1}"
 114         mounts="$(awk '{print $2}' /proc/mounts)"
 115         testpath="$(busybox realpath ${testpath})"
 116
 117         while true
 118         do
 119                 if echo "${mounts}" | grep -qs "^${testpath}"
 120                 then
 121                         set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
 122                         echo ${1}
 123                         break
 124                 else
 125                         testpath=$(dirname $testpath)
 126                 fi
 127         done
 128 }
 129
 130 fs_size ()
 131 {
 132         # Returns used/free fs kbytes + 5% more
 133         # You could pass a block device as ${1} or the mount point as ${2}
 134
 135         dev="${1}"
 136         mountp="${2}"
 137         used="${3}"
 138
 139         if [ -z "${mountp}" ]
 140         then
 141                 mountp="$(where_is_mounted ${dev})"
 142
 143                 if [ -z "${mountp}" ]
 144                 then
 145                         mountp="/mnt/tmp_fs_size"
 146
 147                         mkdir -p "${mountp}"
 148                         mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}" || log_warning_msg "cannot mount -t $(get_fstype ${dev}) -o ro ${dev} ${mountp}"
 149
 150                         doumount=1
 151                 fi
 152         fi
 153
 154         if [ "${used}" = "used" ]
 155         then
 156                 size=$(du -ks ${mountp} | cut -f1)
 157                 size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
 158         else
 159                 # free space
 160                 size="$(df -k | grep -s ${mountp} | awk '{print $4}')"
 161         fi
 162
 163         if [ -n "${doumount}" ]
 164         then
 165                 umount "${mountp}" || log_warning_msg "cannot umount ${mountp}"
 166                 rmdir "${mountp}"
 167         fi
 168
 169         echo "${size}"
 170 }
 171
 172 load_keymap ()
 173 {
 174         # Load custom keymap
 175         if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
 176         then
 177                 loadkeys /etc/boottime.kmap.gz
 178         fi
 179 }
 180
 181 setup_loop ()
 182 {
 183         local fspath=${1}
 184         local module=${2}
 185         local pattern=${3}
 186         local offset=${4}
 187         local encryption=${5}
 188         local readonly=${6}
 189
 190         # the output of setup_loop is evaluated in other functions,
 191         # modprobe leaks kernel options like "libata.dma=0"
 192         # as "options libata dma=0" on stdout, causing serious
 193         # problems therefor, so instead always avoid output to stdout
 194         modprobe -q -b "${module}" 1>/dev/null
 195
 196         udevadm settle
 197
 198         for loopdev in ${pattern}
 199         do
 200                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 201                 then
 202                         dev=$(sys2dev "${loopdev}")
 203                         options=''
 204
 205                         if [ -n "${readonly}" ]
 206                         then
 207                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 208                                 then
 209                                         options="${options} -r"
 210                                 fi
 211                         fi
 212
 213                         if [ 0 -lt "${offset}" ]
 214                         then
 215                                 options="${options} -o ${offset}"
 216                         fi
 217
 218                         if [ -z "${encryption}" ]
 219                         then
 220                                 losetup ${options} "${dev}" "${fspath}"
 221                         else
 222                                 # Loop AES encryption
 223                                 while true
 224                                 do
 225                                         load_keymap
 226
 227                                         echo -n "Enter passphrase for root filesystem: " >&6
 228                                         read -s passphrase
 229                                         echo "${passphrase}" > /tmp/passphrase
 230                                         unset passphrase
 231                                         exec 9</tmp/passphrase
 232                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 233                                         error=${?}
 234                                         exec 9<&-
 235                                         rm -f /tmp/passphrase
 236
 237                                         if [ 0 -eq ${error} ]
 238                                         then
 239                                                 unset error
 240                                                 break
 241                                         fi
 242
 243                                         echo
 244                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 245                                         read answer
 246
 247                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 248                                         then
 249                                                 unset answer
 250                                                 break
 251                                         fi
 252                                 done
 253                         fi
 254
 255                         echo "${dev}"
 256                         return 0
 257                 fi
 258         done
 259
 260         panic "No loop devices available"
 261 }
 262
 263 try_mount ()
 264 {
 265         dev="${1}"
 266         mountp="${2}"
 267         opts="${3}"
 268         fstype="${4}"
 269
 270         old_mountp="$(where_is_mounted ${dev})"
 271
 272         if [ -n "${old_mountp}" ]
 273         then
 274                 if [ "${opts}" != "ro" ]
 275                 then
 276                         mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
 277                 fi
 278
 279                 mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
 280         else
 281                 if [ -z "${fstype}" ]
 282                 then
 283                         fstype=$(get_fstype "${dev}")
 284                 fi
 285                 mount -t "${fstype}" -o "${opts}" "${dev}" "${mountp}" || \
 286                 ( echo "SKIPPING: Cannot mount ${dev} on ${mountp}, fstype=${fstype}, options=${opts}" > live.log && return 0 )
 287         fi
 288 }
 289
 290 find_cow_device ()
 291 {
 292         # Returns a device containing a partition labeled "${pers_label}" or containing a file named the same way
 293         #  in the latter case the partition containing the file is left mounted
 294         #  if is not in black_listed_devices
 295         pers_label="${1}"
 296         cow_backing="/${pers_label}-backing"
 297         black_listed_devices="${2}"
 298
 299         if [ -z "${PERSISTENT_PATH}" ]
 300         then
 301                 pers_fpath=${cow_backing}/${pers_label}
 302         else
 303                 pers_fpath=${cow_backing}/${PERSISTENT_PATH}/${pers_label}
 304         fi
 305
 306         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 307         do
 308                 for dev in $(subdevices "${sysblock}")
 309                 do
 310                         devname=$(sys2dev "${dev}")
 311
 312                         if echo "${black_listed_devices}" | grep -q "${devname}"
 313                         then
 314                                 # skip this device enterely
 315                                 break
 316                         fi
 317
 318                         # Checking for a luks device
 319                         if [ "${PERSISTENT}" = "cryptsetup" ] && [ -e /sbin/cryptsetup ] && /sbin/cryptsetup isLuks ${devname}
 320                         then
 321                                 while true
 322                                 do
 323                                         load_keymap
 324
 325                                         /lib/cryptsetup/askpass "Enter passphrase for ${pers_label} on ${devname}: " | /sbin/cryptsetup -T 1 luksOpen ${devname} $(basename ${devname}) --key-file=-
 326                                         error=${?}
 327
 328                                         devname="/dev/mapper/$(basename ${devname})"
 329
 330                                         if [ 0 -eq ${error} ]
 331                                         then
 332                                                 unset error
 333                                                 break
 334                                         fi
 335
 336                                         echo
 337                                         echo -n "There was an error decrypting ${devname} ... Retry? [Y/n] " >&6
 338                                         read answer
 339
 340                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 341                                         then
 342                                                 unset answer
 343                                                 break
 344                                         fi
 345                                 done
 346                         fi
 347
 348                         # udev (>= 146) no longer provides vol_id
 349                         if [ -x /lib/udev/vol_id ]
 350                         then
 351                                 # lenny
 352                                 if [ "$(/lib/udev/vol_id -l ${devname} 2>/dev/null)" = "${pers_label}" ]
 353                                 then
 354                                         echo "${devname}"
 355                                         return 0
 356                                 fi
 357                         else
 358                                 # squeeze
 359                                 if [ "$(/sbin/blkid -s LABEL -o value $devname 2>/dev/null)" = "${pers_label}" ]
 360                                 then
 361                                         echo "${devname}"
 362                                         return 0
 363                                 fi
 364                         fi
 365
 366                         if [ "${PERSISTENT}" = "nofiles" ]
 367                         then
 368                                 # do not mount the device to find for image files
 369                                 # just skip this
 370                                 continue
 371                         fi
 372
 373                         case "$(get_fstype ${devname})" in
 374                                 vfat|ext2|ext3|ext4|jffs2)
 375                                         mkdir -p "${cow_backing}"
 376                                         if try_mount "${devname}" "${cow_backing}" "rw"
 377                                         then
 378                                                 if [ -f "${pers_fpath}" ]
 379                                                 then
 380                                                         echo $(setup_loop "${pers_fpath}" "loop" "/sys/block/loop*")
 381                                                         return 0
 382                                                 else
 383                                                         umount ${cow_backing} > /dev/null 2>&1 || true
 384                                                 fi
 385                                         fi
 386                                         ;;
 387                                 *)
 388                                         ;;
 389                         esac
 390                 done
 391         done
 392         return 1
 393 }
 394
 395 find_files ()
 396 {
 397         # return the a string composed by device name, mountpoint an the first of ${filenames} found on a supported partition
 398         # FIXME: merge with above function
 399
 400         filenames="${1}"
 401         snap_backing="/snap-backing"
 402         black_listed_devices="${2}"
 403
 404         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 405         do
 406                 for dev in $(subdevices "${sysblock}")
 407                 do
 408                         devname=$(sys2dev "${dev}")
 409                         devfstype="$(get_fstype ${devname})"
 410
 411                         if echo "${black_listed_devices}" | grep -q "${devname}"
 412                         then
 413                                 # skip this device enterely
 414                                 break
 415                         fi
 416
 417                         if is_supported_fs ${devfstype}
 418                         then
 419                                 mkdir -p "${snap_backing}"
 420
 421                                 if try_mount "${devname}" "${snap_backing}" "ro" "${devfstype}"
 422                                 then
 423                                         for filename in ${filenames}
 424                                         do
 425                                                 if [ -f "${snap_backing}/${filename}" ]
 426                                                 then
 427                                                         echo "${devname} ${snap_backing} ${filename}"
 428                                                         umount ${snap_backing}
 429                                                         return 0
 430                                                 fi
 431                                         done
 432                                 fi
 433
 434                                 umount ${snap_backing}
 435                         fi
 436                 done
 437         done
 438 }
 439
 440 get_mac ()
 441 {
 442         mac=""
 443
 444         for adaptor in /sys/class/net/*
 445         do
 446                 status="$(cat ${adaptor}/iflink)"
 447
 448                 if [ "${status}" -eq 2 ]
 449                 then
 450                         mac="$(cat ${adaptor}/address)"
 451                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
 452                 fi
 453         done
 454
 455         echo ${mac}
 456 }
 457
 458 is_luks()
 459 {
 460     devname="${1}"
 461     if [ -x /sbin/cryptsetup ]
 462     then
 463         /sbin/cryptsetup isLuks "${devname}" 2>/dev/null || ret=${?}
 464         return ${ret}
 465     else
 466         return 1
 467     fi
 468
 469 }