scripts/live-helpers

   1 # live-initramfs helper functions, used by live-initramfs 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=${6}
 189
 190         modprobe -q -b "${module}"
 191
 192         udevadm settle
 193
 194         for loopdev in ${pattern}
 195         do
 196                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 197                 then
 198                         dev=$(sys2dev "${loopdev}")
 199                         options=''
 200
 201                         if [ -n "${readonly}" ]
 202                         then
 203                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 204                                 then
 205                                         options="${options} -r"
 206                                 fi
 207                         fi
 208
 209                         if [ 0 -lt "${offset}" ]
 210                         then
 211                                 options="${options} -o ${offset}"
 212                         fi
 213
 214                         if [ -z "${encryption}" ]
 215                         then
 216                                 losetup ${options} "${dev}" "${fspath}"
 217                         else
 218                                 # Loop AES encryption
 219                                 while true
 220                                 do
 221                                         load_keymap
 222
 223                                         echo -n "Enter passphrase for root filesystem: " >&6
 224                                         read -s passphrase
 225                                         echo "${passphrase}" > /tmp/passphrase
 226                                         unset passphrase
 227                                         exec 9</tmp/passphrase
 228                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 229                                         error=${?}
 230                                         exec 9<&-
 231                                         rm -f /tmp/passphrase
 232
 233                                         if [ 0 -eq ${error} ]
 234                                         then
 235                                                 unset error
 236                                                 break
 237                                         fi
 238
 239                                         echo
 240                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 241                                         read answer
 242
 243                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 244                                         then
 245                                                 unset answer
 246                                                 break
 247                                         fi
 248                                 done
 249                         fi
 250
 251                         echo "${dev}"
 252                         return 0
 253                 fi
 254         done
 255
 256         panic "No loop devices available"
 257 }
 258
 259 try_mount ()
 260 {
 261         dev="${1}"
 262         mountp="${2}"
 263         opts="${3}"
 264         fstype="${4}"
 265
 266         old_mountp="$(where_is_mounted ${dev})"
 267
 268         if [ -n "${old_mountp}" ]
 269         then
 270                 if [ "${opts}" != "ro" ]
 271                 then
 272                         mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
 273                 fi
 274
 275                 mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
 276         else
 277                 if [ -z "${fstype}" ]
 278                 then
 279                         fstype=$(get_fstype "${dev}")
 280                 fi
 281                 mount -t "${fstype}" -o "${opts}" "${dev}" "${mountp}" || \
 282                 ( echo "SKIPPING: Cannot mount ${dev} on ${mountp}, fstype=${fstype}, options=${opts}" > live.log && return 0 )
 283         fi
 284 }
 285
 286 find_cow_device ()
 287 {
 288         # Returns a device containing a partition labeled "${pers_label}" or containing a file named the same way
 289         #  in the latter case the partition containing the file is left mounted
 290         #  if is not in black_listed_devices
 291         pers_label="${1}"
 292         cow_backing="/${pers_label}-backing"
 293         black_listed_devices="${2}"
 294
 295         if [ -z "${PERSISTENT_PATH}" ]
 296         then
 297                 pers_fpath=${cow_backing}/${pers_label}
 298         else
 299                 pers_fpath=${cow_backing}/${PERSISTENT_PATH}/${pers_label}
 300         fi
 301
 302         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 303         do
 304                 for dev in $(subdevices "${sysblock}")
 305                 do
 306                         devname=$(sys2dev "${dev}")
 307
 308                         if echo "${black_listed_devices}" | grep -q "${devname}"
 309                         then
 310                                 # skip this device enterely
 311                                 break
 312                         fi
 313
 314                         # Checking for a luks device
 315                         if [ "${PERSISTENT}" = "cryptsetup" ] && [ -e /sbin/cryptsetup ] && /sbin/cryptsetup isLuks ${devname}
 316                         then
 317                                 while true
 318                                 do
 319                                         load_keymap
 320
 321                                         /lib/cryptsetup/askpass "Enter passphrase for ${pers_label} on ${devname}: " | /sbin/cryptsetup -T 1 luksOpen ${devname} $(basename ${devname}) --key-file=-
 322                                         error=${?}
 323
 324                                         devname="/dev/mapper/$(basename ${devname})"
 325
 326                                         if [ 0 -eq ${error} ]
 327                                         then
 328                                                 unset error
 329                                                 break
 330                                         fi
 331
 332                                         echo
 333                                         echo -n "There was an error decrypting ${devname} ... Retry? [Y/n] " >&6
 334                                         read answer
 335
 336                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 337                                         then
 338                                                 unset answer
 339                                                 break
 340                                         fi
 341                                 done
 342                         fi
 343
 344                         # udev (>= 146) no longer provides vol_id
 345                         if [ -x /lib/udev/vol_id ]
 346                         then
 347                                 # lenny
 348                                 if [ "$(/lib/udev/vol_id -l ${devname} 2>/dev/null)" = "${pers_label}" ]
 349                                 then
 350                                         echo "${devname}"
 351                                         return 0
 352                                 fi
 353                         else
 354                                 # squeeze
 355                                 if [ "$(/sbin/blkid -s LABEL -o value $devname 2>/dev/null)" = "${pers_label}" ]
 356                                 then
 357                                         echo "${devname}"
 358                                         return 0
 359                                 fi
 360                         fi
 361
 362                         if [ "${PERSISTENT}" = "nofiles" ]
 363                         then
 364                                 # do not mount the device to find for image files
 365                                 # just skip this
 366                                 continue
 367                         fi
 368
 369                         case "$(get_fstype ${devname})" in
 370                                 vfat|ext2|ext3|ext4|jffs2)
 371                                         mkdir -p "${cow_backing}"
 372                                         if try_mount "${devname}" "${cow_backing}" "rw"
 373                                         then
 374                                                 if [ -f "${pers_fpath}" ]
 375                                                 then
 376                                                         echo $(setup_loop "${pers_fpath}" "loop" "/sys/block/loop*")
 377                                                         return 0
 378                                                 else
 379                                                         umount ${cow_backing} > /dev/null 2>&1 || true
 380                                                 fi
 381                                         fi
 382                                         ;;
 383                                 *)
 384                                         ;;
 385                         esac
 386                 done
 387         done
 388         return 1
 389 }
 390
 391 find_files ()
 392 {
 393         # return the a string composed by device name, mountpoint an the first of ${filenames} found on a supported partition
 394         # FIXME: merge with above function
 395
 396         filenames="${1}"
 397         snap_backing="/snap-backing"
 398         black_listed_devices="${2}"
 399
 400         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 401         do
 402                 for dev in $(subdevices "${sysblock}")
 403                 do
 404                         devname=$(sys2dev "${dev}")
 405                         devfstype="$(get_fstype ${devname})"
 406
 407                         if echo "${black_listed_devices}" | grep -q "${devname}"
 408                         then
 409                                 # skip this device enterely
 410                                 break
 411                         fi
 412
 413                         if is_supported_fs ${devfstype}
 414                         then
 415                                 mkdir -p "${snap_backing}"
 416
 417                                 if try_mount "${devname}" "${snap_backing}" "ro" "${devfstype}"
 418                                 then
 419                                         for filename in ${filenames}
 420                                         do
 421                                                 if [ -f "${snap_backing}/${filename}" ]
 422                                                 then
 423                                                         echo "${devname} ${snap_backing} ${filename}"
 424                                                         umount ${snap_backing}
 425                                                         return 0
 426                                                 fi
 427                                         done
 428                                 fi
 429
 430                                 umount ${snap_backing}
 431                         fi
 432                 done
 433         done
 434 }
 435
 436 get_mac ()
 437 {
 438         mac=""
 439
 440         for adaptor in /sys/class/net/*
 441         do
 442                 status="$(cat ${adaptor}/iflink)"
 443
 444                 if [ "${status}" -eq 2 ]
 445                 then
 446                         mac="$(cat ${adaptor}/address)"
 447                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
 448                 fi
 449         done
 450
 451         echo ${mac}
 452 }
 453
 454 is_luks()
 455 {
 456     devname="${1}"
 457     if [ -x /sbin/cryptsetup ]
 458     then
 459         /sbin/cryptsetup isLuks "${devname}" 2>/dev/null || ret=${?}
 460         return ${ret}
 461     else
 462         return 1
 463     fi
 464
 465 }