scripts/live-helpers

   1 #!/bin/sh
   2 # live-initramfs helper functions, used by live-initramfs on boot and by live-snapshot
   3
   4 if [ ! -x "/bin/fstype" ]
   5 then
   6         # klibc not in path -> not in initramfs
   7         export PATH="${PATH}:/usr/lib/klibc/bin"
   8 fi
   9
  10 sys2dev ()
  11 {
  12         sysdev=${1#/sys}
  13         echo "/dev/$(udevinfo -q name -p ${sysdev} 2>/dev/null|| echo ${sysdev##*/})"
  14 }
  15
  16 subdevices ()
  17 {
  18         sysblock=${1}
  19         r=""
  20
  21         for dev in "${sysblock}" "${sysblock}"/*
  22         do
  23                 if [ -e "${dev}/dev" ]
  24                 then
  25                         r="${r} ${dev}"
  26                 fi
  27         done
  28
  29         echo ${r}
  30 }
  31
  32 get_fstype ()
  33 {
  34         local FSTYPE
  35         local FSSIZE
  36
  37         # fstype misreports LUKS devices
  38         if is_luks "${1}"
  39         then
  40             /lib/udev/vol_id -t ${1} 2>/dev/null
  41             return
  42         fi
  43
  44         eval $(fstype < ${1})
  45
  46         if [ "${FSTYPE}" != "unknown" ]
  47         then
  48                 echo ${FSTYPE}
  49                 return 0
  50         fi
  51
  52         /lib/udev/vol_id -t ${1} 2>/dev/null
  53 }
  54
  55 where_is_mounted ()
  56 {
  57         device=${1}
  58
  59         if grep -q "^${device} " /proc/mounts
  60         then
  61                 grep "^${device} " /proc/mounts | read d mountpoint rest
  62                 echo ${mountpoint}
  63                 return 0
  64         fi
  65
  66         return 1
  67 }
  68
  69 lastline ()
  70 {
  71         while read lines
  72         do
  73                 line=${lines}
  74         done
  75
  76         echo "${line}"
  77 }
  78
  79 base_path ()
  80 {
  81         testpath="${1}"
  82         mounts="$(awk '{print $2}' /proc/mounts)"
  83         testpath="$(busybox realpath ${testpath})"
  84
  85         while true
  86         do
  87                 if echo "${mounts}" | grep -qs "^${testpath}"
  88                 then
  89                         set -- $(echo "${mounts}" | grep "^${testpath}" | lastline)
  90                         echo ${1}
  91                         break
  92                 else
  93                         testpath=$(dirname $testpath)
  94                 fi
  95         done
  96 }
  97
  98 fs_size ()
  99 {
 100         # Returns used/free fs kbytes + 5% more
 101         # You could pass a block device as ${1} or the mount point as ${2}
 102
 103         dev="${1}"
 104         mountp="${2}"
 105         used="${3}"
 106
 107         if [ -z "${mountp}" ]
 108         then
 109                 mountp=$(where_is_mounted "${dev}")
 110
 111                 if [ "${?}" -gt 0 ]
 112                 then
 113                         mountp="/mnt/tmp_fs_size"
 114
 115                         mkdir -p "${mountp}"
 116                         mount -t $(get_fstype "${dev}") -o ro "${dev}" "${mountp}"
 117
 118                         doumount=1
 119                 fi
 120         fi
 121
 122         if [ "${used}" = "used" ]
 123         then
 124                 size=$(du -ks ${mountp} | cut -f1)
 125                 size=$(expr ${size} + ${size} / 20 ) # FIXME: 5% more to be sure
 126         else
 127                 # free space
 128                 size="$(df -k | grep -s ${mountp} | awk '{print $4}')"
 129         fi
 130
 131         if [ -n "${doumount}" ]
 132         then
 133                 umount "${mountp}"
 134                 rmdir "${mountp}"
 135         fi
 136
 137         echo "${size}"
 138 }
 139
 140 load_keymap ()
 141 {
 142         # Load custom keymap
 143         if [ -x /bin/loadkeys -a -r /etc/boottime.kmap.gz ]
 144         then
 145                 loadkeys /etc/boottime.kmap.gz
 146         fi
 147 }
 148
 149 setup_loop ()
 150 {
 151         local fspath=${1}
 152         local module=${2}
 153         local pattern=${3}
 154         local offset=${4}
 155         local encryption=${5}
 156
 157         modprobe -q -b "${module}"
 158         udevsettle
 159
 160         for loopdev in ${pattern}
 161         do
 162                 if [ "$(cat ${loopdev}/size)" -eq 0 ]
 163                 then
 164                         dev=$(sys2dev "${loopdev}")
 165                         options=''
 166
 167                         if [ 0 -lt "${offset}" ]
 168                         then
 169                                 options="${options} -o ${offset}"
 170                         fi
 171
 172                         if [ -z "${encryption}" ]
 173                         then
 174                                 losetup ${options} "${dev}" "${fspath}"
 175                         else
 176                                 # Loop AES encryption
 177                                 while true
 178                                 do
 179                                         load_keymap
 180
 181                                         echo -n "Enter passphrase for root filesystem: " >&6
 182                                         read -s passphrase
 183                                         echo "${passphrase}" > /tmp/passphrase
 184                                         unset passphrase
 185                                         exec 9</tmp/passphrase
 186                                         /sbin/losetup ${options} -e "${encryption}" -p 9 "${dev}" "${fspath}"
 187                                         error=${?}
 188                                         exec 9<&-
 189                                         rm -f /tmp/passphrase
 190
 191                                         if [ 0 -eq ${error} ]
 192                                         then
 193                                                 unset error
 194                                                 break
 195                                         fi
 196
 197                                         echo
 198                                         echo -n "There was an error decrypting the root filesystem ... Retry? [Y/n] " >&6
 199                                         read answer
 200
 201                                         if [ "$(echo "${answer}" | cut -b1 | tr A-Z a-z)" = "n" ]
 202                                         then
 203                                                 unset answer
 204                                                 break
 205                                         fi
 206                                 done
 207                         fi
 208
 209                         echo "${dev}"
 210                         return 0
 211                 fi
 212         done
 213
 214         panic "No loop devices available"
 215 }
 216
 217 try_mount ()
 218 {
 219         dev="${1}"
 220         mountp="${2}"
 221         opts="${3}"
 222
 223         if where_is_mounted ${dev} > /dev/null
 224         then
 225                 mount -o remount,"${opts}" ${dev} $(where_is_mounted ${dev}) || panic "Remounting failed"
 226                 mount -o bind $(where_is_mounted ${dev}) ${mountp} || panic "Cannot bind-mount"
 227         else
 228                 mount -t $(get_fstype "${dev}") -o "${opts}" "${dev}" "${mountp}" || panic "Cannot mount ${dev} on ${mountp}"
 229         fi
 230 }
 231
 232 find_cow_device ()
 233 {
 234         pers_label="${1}"
 235         cow_backing="/${pers_label}-backing"
 236
 237         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 238         do
 239                 for dev in $(subdevices "${sysblock}")
 240                 do
 241                         devname=$(sys2dev "${dev}")
 242
 243                         if [ "$(/lib/udev/vol_id -l ${devname} 2>/dev/null)" = "${pers_label}" ]
 244                         then
 245                                 echo "${devname}"
 246                                 return
 247                         fi
 248
 249                         case "$(get_fstype ${devname})" in
 250                                 vfat|ext2|ext3|jffs2)
 251                                         mkdir -p "${cow_backing}"
 252                                         try_mount "${devname}" "${cow_backing}" "rw"
 253
 254                                         if [ -f "${cow_backing}/${pers_label}" ]
 255                                         then
 256                                                 echo $(setup_loop "${cow_backing}/${pers_label}" "loop" "/sys/block/loop*")
 257                                                 return 0
 258                                         else
 259                                                 umount ${cow_backing}
 260                                         fi
 261                                         ;;
 262                                 *)
 263                                         ;;
 264                         esac
 265                 done
 266         done
 267 }
 268
 269 find_files ()
 270 {
 271         # return the first of ${filenames} found on vfat and ext2/ext3 devices
 272         # FIXME: merge with above function
 273
 274         filenames="${1}"
 275         snap_backing="/snap-backing"
 276
 277         for sysblock in $(echo /sys/block/* | tr ' ' '\n' | grep -v loop | grep -v ram | grep -v fd)
 278         do
 279                 for dev in $(subdevices "${sysblock}")
 280                 do
 281                         devname=$(sys2dev "${dev}")
 282                         devfstype="$(get_fstype ${devname})"
 283
 284                         case "${devfstype}" in
 285                                 vfat|ext2|ext3|jffs2)
 286                                         # FIXME: all supported block devices should be scanned
 287                                         mkdir -p "${snap_backing}"
 288                                         try_mount "${devname}" "${snap_backing}" "ro"
 289
 290                                         for filename in ${filenames}
 291                                         do
 292                                                 if [ -f "${snap_backing}/${filename}" ]
 293                                                 then
 294                                                         echo "${devname} ${snap_backing} ${filename}"
 295                                                         return 0
 296                                                 fi
 297                                         done
 298
 299                                         umount ${snap_backing}
 300                                         ;;
 301                         esac
 302                 done
 303         done
 304 }
 305
 306 get_mac ()
 307 {
 308         mac=""
 309
 310         for adaptor in /sys/class/net/*
 311         do
 312                 status="$(cat ${adaptor}/iflink)"
 313
 314                 if [ "${status}" -eq 2 ]
 315                 then
 316                         mac="$(cat ${adaptor}/address)"
 317                         mac="$(echo ${mac} | sed 's/:/-/g' | tr '[a-z]' '[A-Z]')"
 318                 fi
 319         done
 320
 321         echo ${mac}
 322 }
 323
 324 is_luks()
 325 {
 326     devname="${1}"
 327     if [ -x /sbin/cryptsetup ]
 328     then
 329         /sbin/cryptsetup isLuks "${devname}" 2>/dev/null || ret=${?}
 330         return ${ret}
 331     else
 332         return 1
 333     fi
 334
 335 }