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