scripts/live-helpers

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