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 >=146-1 no longer provides vol_id:
  80         if [ -x /lib/udev/vol_id ]
  81         then
  82                 /lib/udev/vol_id -t ${1} 2>/dev/null
  83         else
  84                 eval $(blkid -o udev "${1}")
  85                 if [ -n "$ID_FS_TYPE" ]
  86                 then
  87                         echo "${ID_FS_TYPE}"
  88                 fi
  89         fi
  90 }
  91
  92 where_is_mounted ()
  93 {
  94         device=${1}
  95
  96         if grep -q "^${device} " /proc/mounts
  97         then
  98                 # return the first found
  99                 grep -m1 "^${device} " /proc/mounts | cut -f2 -d ' '
 100         fi
 101 }
 102
 103 lastline ()
 104 {
 105         while read lines
 106         do
 107                 line=${lines}
 108         done
 109
 110         echo "${line}"
 111 }
 112
 113 base_path ()
 114 {
 115         testpath="${1}"
 116         mounts="$(awk '{print $2}' /proc/mounts)"
 117         testpath="$(busybox realpath ${testpath})"
 118
 119         while true
 120         do
 121                 if echo "${mounts}" | grep -qs "^${testpath}"
 122                 then
 123                         set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
 124                         echo ${1}
 125                         break
 126                 else
 127                         testpath=$(dirname $testpath)
 128                 fi
 129         done
 130 }
 131
 132 fs_size ()
 133 {
 134         # Returns used/free fs kbytes + 5% more
 135         # You could pass a block device as ${1} or the mount point as ${2}
 136
 137         dev="${1}"
 138         mountp="${2}"
 139         used="${3}"
 140
 141         if [ -z "${mountp}" ]
 142         then
 143                 mountp="$(where_is_mounted ${dev})"
 144
 145                 if [ -z "${mountp}" ]
 146                 then
 147                         mountp="/mnt/tmp_fs_size"
 148
 149                         mkdir -p "${mountp}"
 150                         mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}" || log_warning_msg "cannot mount -t $(get_fstype ${dev}) -o ro ${dev} ${mountp}"
 151
 152                         doumount=1
 153                 fi
 154         fi
 155
 156         if [ "${used}" = "used" ]
 157         then
 158                 size=$(du -ks ${mountp} | cut -f1)
 159                 size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
 160         else
 161                 # free space
 162                 size="$(df -k | grep -s ${mountp} | awk '{print $4}')"
 163         fi
 164
 165         if [ -n "${doumount}" ]
 166         then
 167                 umount "${mountp}" || log_warning_msg "cannot umount ${mountp}"
 168                 rmdir "${mountp}"
 169         fi
 170
 171         echo "${size}"
 172 }
 173
 174 load_keymap ()
 175 {
 176         # Load custom keymap
 177         if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
 178         then
 179                 loadkeys /etc/boottime.kmap.gz
 180         fi
 181 }
 182
 183 setup_loop ()
 184 {
 185         local fspath=${1}
 186         local module=${2}
 187         local pattern=${3}
 188         local offset=${4}
 189         local encryption=${5}
 190         local readonly=${6}
 191
 192         modprobe -q -b "${module}"
 193
 194         if [ -x /sbin/udevadm ]
 195         then
 196                 # lenny
 197                 udevadm settle
 198         else
 199                 # etch
 200                 udevsettle
 201         fi
 202
 203         for loopdev in ${pattern}
 204         do
 205                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 206                 then
 207                         dev=$(sys2dev "${loopdev}")
 208                         options=''
 209
 210                         if [ -n "${readonly}" ]
 211                         then
 212                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 213                                 then
 214                                         options="${options} -r"
 215                                 fi
 216                         fi
 217
 218                         if [ 0 -lt "${offset}" ]
 219                         then
 220                                 options="${options} -o ${offset}"
 221                         fi
 222
 223                         if [ -z "${encryption}" ]
 224                         then
 225                                 losetup ${options} "${dev}" "${fspath}"
 226                         else
 227                                 # Loop AES encryption
 228                                 while true
 229                                 do
 230                                         load_keymap
 231
 232                                         echo -n "Enter passphrase for root filesystem: " >&6
 233                                         read -s passphrase
 234                                         echo "${passphrase}" > /tmp/passphrase
 235                                         unset passphrase
 236                                         exec 9</tmp/passphrase
 237                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 238                                         error=${?}
 239                                         exec 9<&-
 240                                         rm -f /tmp/passphrase
 241
 242                                         if [ 0 -eq ${error} ]
 243                                         then
 244                                                 unset error
 245                                                 break
 246                                         fi
 247
 248                                         echo
 249                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 250                                         read answer
 251
 252                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 253                                         then
 254                                                 unset answer
 255                                                 break
 256                                         fi
 257                                 done
 258                         fi
 259
 260                         echo "${dev}"
 261                         return 0
 262                 fi
 263         done
 264
 265         panic "No loop devices available"
 266 }
 267
 268 try_mount ()
 269 {
 270         dev="${1}"
 271         mountp="${2}"
 272         opts="${3}"
 273         fstype="${4}"
 274
 275         old_mountp="$(where_is_mounted ${dev})"
 276
 277         if [ -n "${old_mountp}" ]
 278         then
 279                 if [ "${opts}" != "ro" ]
 280                 then
 281                         mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
 282                 fi
 283
 284                 mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
 285         else
 286                 if [ -z "${fstype}" ]
 287                 then
 288                         fstype=$(get_fstype "${dev}")
 289                 fi
 290                 mount -t "${fstype}" -o "${opts}" "${dev}" "${mountp}" || panic "Cannot mount ${dev} on ${mountp}, fstype=${fstype}, options=${opts}"
 291         fi
 292 }
 293
 294 find_cow_device ()
 295 {
 296         # Returns a device containing a partition labeled "${pers_label}" or containing a file named the same way
 297         #  in the latter case the partition containing the file is left mounted
 298         #  if is not in black_listed_devices
 299         pers_label="${1}"
 300         cow_backing="/${pers_label}-backing"
 301         black_listed_devices="${2}"
 302
 303         if [ -z "${PERSISTENT_PATH}" ]
 304         then
 305                 pers_fpath=${cow_backing}/${pers_label}
 306         else
 307                 pers_fpath=${cow_backing}/${PERSISTENT_PATH}/${pers_label}
 308         fi
 309
 310         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 311         do
 312                 for dev in $(subdevices "${sysblock}")
 313                 do
 314                         devname=$(sys2dev "${dev}")
 315
 316                         if echo "${black_listed_devices}" | grep -q "${devname}"
 317                         then
 318                                 # skip this device enterely
 319                                 break
 320                         fi
 321
 322                         # Checking for a luks device
 323                         if [ "${PERSISTENT}" = "cryptsetup" ] && [ -e /sbin/cryptsetup ] && /sbin/cryptsetup isLuks ${devname}
 324                         then
 325                                 while true
 326                                 do
 327                                         load_keymap
 328
 329                                         /lib/cryptsetup/askpass "Enter passphrase for ${pers_label} on ${devname}: " | /sbin/cryptsetup -T 1 luksOpen ${devname} $(basename ${devname}) --key-file=-
 330                                         error=${?}
 331
 332                                         devname="/dev/mapper/$(basename ${devname})"
 333
 334                                         if [ 0 -eq ${error} ]
 335                                         then
 336                                                 unset error
 337                                                 break
 338                                         fi
 339
 340                                         echo
 341                                         echo -n "There was an error decrypting ${devname} ... Retry? [Y/n] " >&6
 342                                         read answer
 343
 344                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 345                                         then
 346                                                 unset answer
 347                                                 break
 348                                         fi
 349                                 done
 350                         fi
 351
 352                         # udev >=146-1 no longer provides vol_id:
 353                         if [ -x /lib/udev/vol_id ]
 354                         then
 355                                 if [ "$(/lib/udev/vol_id -l ${devname} 2>/dev/null)" = "${pers_label}" ]
 356                                 then
 357                                         echo "${devname}"
 358                                         return 0
 359                                 fi
 360                         else
 361                                 eval $(blkid -o udev "${devname}")
 362                                 if [ "$ID_FS_LABEL" = "${pers_label}" ]
 363                                 then
 364                                         echo "${devname}"
 365                                         return 0
 366                                 fi
 367                         fi
 368
 369                         if [ "${PERSISTENT}" = "nofiles" ]
 370                         then
 371                                 # do not mount the device to find for image files
 372                                 # just skip this
 373                                 continue
 374                         fi
 375
 376                         case "$(get_fstype ${devname})" in
 377                                 vfat|ext2|ext3|ext4|jffs2)
 378                                         mkdir -p "${cow_backing}"
 379                                         if ! try_mount "${devname}" "${cow_backing}" "rw"
 380                                         then
 381                                                 break
 382                                         fi
 383
 384                                         if [ -f "${pers_fpath}" ]
 385                                         then
 386                                                 echo $(setup_loop "${pers_fpath}" "loop" "/sys/block/loop*")
 387                                                 return 0
 388                                         else
 389                                                 umount ${cow_backing}
 390                                         fi
 391                                         ;;
 392                                 *)
 393                                         ;;
 394                         esac
 395                 done
 396         done
 397         return 1
 398 }
 399
 400 find_files ()
 401 {
 402         # return the a string composed by device name, mountpoint an the first of ${filenames} found on a supported partition
 403         # FIXME: merge with above function
 404
 405         filenames="${1}"
 406         snap_backing="/snap-backing"
 407         black_listed_devices="${2}"
 408
 409         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 410         do
 411                 for dev in $(subdevices "${sysblock}")
 412                 do
 413                         devname=$(sys2dev "${dev}")
 414                         devfstype="$(get_fstype ${devname})"
 415
 416                         if echo "${black_listed_devices}" | grep -q "${devname}"
 417                         then
 418                                 # skip this device enterely
 419                                 break
 420                         fi
 421
 422                         if is_supported_fs ${devfstype}
 423                         then
 424                                 mkdir -p "${snap_backing}"
 425
 426                                 if try_mount "${devname}" "${snap_backing}" "ro" "${devfstype}"
 427                                 then
 428                                         for filename in ${filenames}
 429                                         do
 430                                                 if [ -f "${snap_backing}/${filename}" ]
 431                                                 then
 432                                                         echo "${devname} ${snap_backing} ${filename}"
 433                                                         umount ${snap_backing}
 434                                                         return 0
 435                                                 fi
 436                                         done
 437                                 fi
 438
 439                                 umount ${snap_backing}
 440                         fi
 441                 done
 442         done
 443 }
 444
 445 get_mac ()
 446 {
 447         mac=""
 448
 449         for adaptor in /sys/class/net/*
 450         do
 451                 status="$(cat ${adaptor}/iflink)"
 452
 453                 if [ "${status}" -eq 2 ]
 454                 then
 455                         mac="$(cat ${adaptor}/address)"
 456                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
 457                 fi
 458         done
 459
 460         echo ${mac}
 461 }
 462
 463 is_luks()
 464 {
 465     devname="${1}"
 466     if [ -x /sbin/cryptsetup ]
 467     then
 468         /sbin/cryptsetup isLuks "${devname}" 2>/dev/null || ret=${?}
 469         return ${ret}
 470     else
 471         return 1
 472     fi
 473
 474 }