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         udevadm settle
 195
 196         for loopdev in ${pattern}
 197         do
 198                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 199                 then
 200                         dev=$(sys2dev "${loopdev}")
 201                         options=''
 202
 203                         if [ -n "${readonly}" ]
 204                         then
 205                                 if losetup --help 2>&1 | grep -q -- "-r\b"
 206                                 then
 207                                         options="${options} -r"
 208                                 fi
 209                         fi
 210
 211                         if [ 0 -lt "${offset}" ]
 212                         then
 213                                 options="${options} -o ${offset}"
 214                         fi
 215
 216                         if [ -z "${encryption}" ]
 217                         then
 218                                 losetup ${options} "${dev}" "${fspath}"
 219                         else
 220                                 # Loop AES encryption
 221                                 while true
 222                                 do
 223                                         load_keymap
 224
 225                                         echo -n "Enter passphrase for root filesystem: " >&6
 226                                         read -s passphrase
 227                                         echo "${passphrase}" > /tmp/passphrase
 228                                         unset passphrase
 229                                         exec 9</tmp/passphrase
 230                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 231                                         error=${?}
 232                                         exec 9<&-
 233                                         rm -f /tmp/passphrase
 234
 235                                         if [ 0 -eq ${error} ]
 236                                         then
 237                                                 unset error
 238                                                 break
 239                                         fi
 240
 241                                         echo
 242                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 243                                         read answer
 244
 245                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 246                                         then
 247                                                 unset answer
 248                                                 break
 249                                         fi
 250                                 done
 251                         fi
 252
 253                         echo "${dev}"
 254                         return 0
 255                 fi
 256         done
 257
 258         panic "No loop devices available"
 259 }
 260
 261 try_mount ()
 262 {
 263         dev="${1}"
 264         mountp="${2}"
 265         opts="${3}"
 266         fstype="${4}"
 267
 268         old_mountp="$(where_is_mounted ${dev})"
 269
 270         if [ -n "${old_mountp}" ]
 271         then
 272                 if [ "${opts}" != "ro" ]
 273                 then
 274                         mount -o remount,"${opts}" "${dev}" "${old_mountp}" || panic "Remounting ${dev} ${opts} on ${old_mountp} failed"
 275                 fi
 276
 277                 mount -o bind "${old_mountp}" "${mountp}" || panic "Cannot bind-mount ${old_mountp} on ${mountp}"
 278         else
 279                 if [ -z "${fstype}" ]
 280                 then
 281                         fstype=$(get_fstype "${dev}")
 282                 fi
 283                 mount -t "${fstype}" -o "${opts}" "${dev}" "${mountp}" || \
 284                 ( echo "SKIPPING: Cannot mount ${dev} on ${mountp}, fstype=${fstype}, options=${opts}" > live.log && return 0 )
 285         fi
 286 }
 287
 288 find_cow_device ()
 289 {
 290         # Returns a device containing a partition labeled "${pers_label}" or containing a file named the same way
 291         #  in the latter case the partition containing the file is left mounted
 292         #  if is not in black_listed_devices
 293         pers_label="${1}"
 294         cow_backing="/${pers_label}-backing"
 295         black_listed_devices="${2}"
 296
 297         if [ -z "${PERSISTENT_PATH}" ]
 298         then
 299                 pers_fpath=${cow_backing}/${pers_label}
 300         else
 301                 pers_fpath=${cow_backing}/${PERSISTENT_PATH}/${pers_label}
 302         fi
 303
 304         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 305         do
 306                 for dev in $(subdevices "${sysblock}")
 307                 do
 308                         devname=$(sys2dev "${dev}")
 309
 310                         if echo "${black_listed_devices}" | grep -q "${devname}"
 311                         then
 312                                 # skip this device enterely
 313                                 break
 314                         fi
 315
 316                         # Checking for a luks device
 317                         if [ "${PERSISTENT}" = "cryptsetup" ] && [ -e /sbin/cryptsetup ] && /sbin/cryptsetup isLuks ${devname}
 318                         then
 319                                 while true
 320                                 do
 321                                         load_keymap
 322
 323                                         /lib/cryptsetup/askpass "Enter passphrase for ${pers_label} on ${devname}: " | /sbin/cryptsetup -T 1 luksOpen ${devname} $(basename ${devname}) --key-file=-
 324                                         error=${?}
 325
 326                                         devname="/dev/mapper/$(basename ${devname})"
 327
 328                                         if [ 0 -eq ${error} ]
 329                                         then
 330                                                 unset error
 331                                                 break
 332                                         fi
 333
 334                                         echo
 335                                         echo -n "There was an error decrypting ${devname} ... Retry? [Y/n] " >&6
 336                                         read answer
 337
 338                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 339                                         then
 340                                                 unset answer
 341                                                 break
 342                                         fi
 343                                 done
 344                         fi
 345
 346                         # udev >=146-1 no longer provides vol_id:
 347                         if [ -x /lib/udev/vol_id ]
 348                         then
 349                                 if [ "$(/lib/udev/vol_id -l ${devname} 2>/dev/null)" = "${pers_label}" ]
 350                                 then
 351                                         echo "${devname}"
 352                                         return 0
 353                                 fi
 354                         else
 355                                 eval $(blkid -o udev "${devname}")
 356                                 if [ "$ID_FS_LABEL" = "${pers_label}" ]
 357                                 then
 358                                         echo "${devname}"
 359                                         return 0
 360                                 fi
 361                         fi
 362
 363                         if [ "${PERSISTENT}" = "nofiles" ]
 364                         then
 365                                 # do not mount the device to find for image files
 366                                 # just skip this
 367                                 continue
 368                         fi
 369
 370                         case "$(get_fstype ${devname})" in
 371                                 vfat|ext2|ext3|ext4|jffs2)
 372                                         mkdir -p "${cow_backing}"
 373                                         if try_mount "${devname}" "${cow_backing}" "rw"
 374                                         then
 375                                                 if [ -f "${pers_fpath}" ]
 376                                                 then
 377                                                         echo $(setup_loop "${pers_fpath}" "loop" "/sys/block/loop*")
 378                                                         return 0
 379                                                 else
 380                                                         umount ${cow_backing} > /dev/null 2>&1 || true
 381                                                 fi
 382                                         fi
 383                                         ;;
 384                                 *)
 385                                         ;;
 386                         esac
 387                 done
 388         done
 389         return 1
 390 }
 391
 392 find_files ()
 393 {
 394         # return the a string composed by device name, mountpoint an the first of ${filenames} found on a supported partition
 395         # FIXME: merge with above function
 396
 397         filenames="${1}"
 398         snap_backing="/snap-backing"
 399         black_listed_devices="${2}"
 400
 401         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 402         do
 403                 for dev in $(subdevices "${sysblock}")
 404                 do
 405                         devname=$(sys2dev "${dev}")
 406                         devfstype="$(get_fstype ${devname})"
 407
 408                         if echo "${black_listed_devices}" | grep -q "${devname}"
 409                         then
 410                                 # skip this device enterely
 411                                 break
 412                         fi
 413
 414                         if is_supported_fs ${devfstype}
 415                         then
 416                                 mkdir -p "${snap_backing}"
 417
 418                                 if try_mount "${devname}" "${snap_backing}" "ro" "${devfstype}"
 419                                 then
 420                                         for filename in ${filenames}
 421                                         do
 422                                                 if [ -f "${snap_backing}/${filename}" ]
 423                                                 then
 424                                                         echo "${devname} ${snap_backing} ${filename}"
 425                                                         umount ${snap_backing}
 426                                                         return 0
 427                                                 fi
 428                                         done
 429                                 fi
 430
 431                                 umount ${snap_backing}
 432                         fi
 433                 done
 434         done
 435 }
 436
 437 get_mac ()
 438 {
 439         mac=""
 440
 441         for adaptor in /sys/class/net/*
 442         do
 443                 status="$(cat ${adaptor}/iflink)"
 444
 445                 if [ "${status}" -eq 2 ]
 446                 then
 447                         mac="$(cat ${adaptor}/address)"
 448                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
 449                 fi
 450         done
 451
 452         echo ${mac}
 453 }
 454
 455 is_luks()
 456 {
 457     devname="${1}"
 458     if [ -x /sbin/cryptsetup ]
 459     then
 460         /sbin/cryptsetup isLuks "${devname}" 2>/dev/null || ret=${?}
 461         return ${ret}
 462     else
 463         return 1
 464     fi
 465
 466 }