path: root/src/initrd/grok-block

#!/bin/sh
. common.sh

DEVNAME=$1
case "$DEVNAME" in /dev/loop*|/dev/ram*|/dev/dm-*|/dev/md*|/dev/fd*) exit ;; esac
[ -b "$DEVNAME" ] || exit

debug_log "grok-block.${DEVNAME##*/}"

addmenu_choosekey()
{
  dev=$1
  dir=$2
  addmenu "$dev//$dir" \
	  "[ Use the GPG key on $dev ]" \
          "menu-select boot-gpg $dev $dir"
}

addmenu_repairhfs()
{
  local device="$1"
  addmenu "$device//reboot" \
    "[ Reboot into Mac OS X in order to repair disk $device ]" \
    "eject /cdrom; sleep 2; reboot -f"
  addmenu "$device//fsck" \
    "[ (DANGEROUS) Try to repair errors on $device with fsck.hfsplus ]" \
    "/bin/openvt -sw -- sh -c 'fsck.hfsplus $device && remenu'"
}

addmenu_chooseroot()
{
  local device="$1" loopfile="$2"

  addmenu "$device//$loopfile" \
    "[ Boot the system on $device${loopfile:+ in file $(basename $loopfile)} ]" \
    "menu-select --fs=$ID_FS_TYPE boot-luks $device ${loopfile:-$device}"
}

addmenu_choose_native_root()
{
    local device="$1" loopfile="$2"
    addmenu "$device//$device" \
            "[ Boot the system on $device ]" \
            "menu-select --fs=$ID_FS_TYPE boot-native $device"
}

addmenu_makeroot()
{
  local device="$1" loopfile="$2" megs="$3" copy_cdrom="$4"
  (
    addmenu "$device//$loopfile" \
      "[ Install Samizdat to $device (in file $(basename $loopfile)) ]" \
      "menu-select --fs=$ID_FS_TYPE boot-new $device $loopfile $megs $copy_cdrom"
  ) &
}

addmenu_destroy_hard_drive()
{
    local device="$1"
    (
        addmenu "$device//$device" \
                "[ Install Samizdat to $device -- THIS DESTROYS ALL DATA ]" \
                "menu-select boot-destroy-disk $device"
    ) &
}

retry_mount()
{
  tries=20
  until mntout="$(mount "$@" 2>&1)"
  do
    tries=$(( tries - 1 ))
    case "$mntout" in
      *"Device or resource busy"*)
        if [ $tries -le 0 ]; then
          warn "mount $@ failed: $mntout"
          return 1
        else
          sleep 1
          continue
        fi
        ;;
      *)
        warn "mount $@ failed: $mntout"
        break ;;
    esac
  done
}

Gpg2()
{
    gpg2 --lock-never --no-permission-warning --no-auto-check-trustdb --no-options "$@"
}

gpg_verify()
{
  [ -e "$1" ] || return
  bootwait samizdat-gpg
  export GNUPGHOME=/gpg/gnupghome
  Gpg2 --verify "$1"
}

gpg_can_decrypt()
{
  [ -e "$1" ] || return
  bootwait samizdat-gpg
  Gpg2 --decrypt "$1" | Gpg2 --decrypt "$1" >/dev/null
}

is_lvm()
{
  for n in 0 1 2 3; do
    [ "LVM2 001" = "$(dd if="$1" bs=1 skip=$((512*n+24)) count=8 2>/dev/null)" ] && return 0
  done
  return 1
}

is_device_without_partitions()
{
    case "$1" in /dev/nbd*|/dev/sr*|*[0-9]) return 1 ;; esac

    [ "$(parted -sm "$1" print | grep -c :)" = 1 ]
}

is_incomplete_samizdat_install()
{
    # TODO: Possibly only some of the partitions are incomplete
    local partition_names="$(parted -sm "$1" print | sed 1,2d | awk -F: -e '{printf "%s:", $6}')"
    [ "$partition_names" = 'samizdat-grub-incomplete:samizdat-plaintext-incomplete:samizdat-luks-encrypted-incomplete:' ]
}

parent_device()
{
    local d="$1"
    while [ "$d" != "${d%[0-9]}" ]; do d=${d%[0-9]}; done
    printf '%s' "$d"
}

wait_for_files_()
{
    : wait_for_files: Polling...
    (
        set +x
        local f
        for f in "$@"; do
            while ! [ -e "$f" ]; do sleep 0.1; done
        done
    )
    : wait_for_files: ...finished.
}

grok_block()
{
  local mountpoint="/mnt/${DEVNAME##*/}"

  mkdir -p "$mountpoint"

  case "$ID_FS_TYPE" in
    ntfs) mount_type='-t ntfs-3g' ;;
    "")   mount_type= ;;
    *)    mount_type="-t $ID_FS_TYPE" ;;
  esac

  # Skip partitions that we created.
  # The name 'samizdat-plaintext' is recognized and used to add the menu entry, below.
  case "$DEVNAME" in
      # Avoid mouting this multiple times in case this script gets called multiple times,
      # because while it's mounted, the dmsetup stuff will fail with device busy.
    /dev/nbd0)
      if [ -e /bootwait/samizdat-nbd-dev ]
        then
            return
        else
            bootwait nbd-script
            wait_for_files_ /sys/block/nbd0/pid
      fi
    ;;
  esac
  case "$ID_PART_ENTRY_NAME" in
      samizdat-grub-incomplete|samizdat-plaintext-incomplete|samizdat-luks-encrypted-incomplete) return ;;
      samizdat-grub|samizdat-luks-encrypted) return ;;
  esac

  if [ "$ID_FS_TYPE" = hfsplus ] && ! fsck.hfsplus -q "$DEVNAME"; then
    (if fsck.hfsplus "$DEVNAME"; then
      grok-block "$DEVNAME"
    else
      addmenu_repairhfs "$DEVNAME"
    fi) &
    return
  fi

  if ! mountpoint -q "$mountpoint"; then
    retry_mount $mount_type -o ro "$DEVNAME" "$mountpoint"
  fi

  if ! mountpoint -q "$mountpoint"; then
      rmdir "$mountpoint"
      is_device_without_partitions "$DEVNAME" ||
          is_incomplete_samizdat_install "$DEVNAME" &&
              addmenu_destroy_hard_drive "$DEVNAME"

      # TODO: Need option to boot the partitions we create
      # TODO: And what if we create partitions and then reboot the machine mid-install?

  elif [ "$ID_PART_ENTRY_NAME" = samizdat-plaintext ]; then
    if gpg_verify "$mountpoint"/disk.key && gpg_can_decrypt "$mountpoint"/disk.key; then
      addmenu_choose_native_root "$(parent_device "$DEVNAME")"
    fi
    umount "$mountpoint"

  elif [ "$DEVNAME" = /dev/nbd0 ]; then
    # This is our rootfs, over the network
    umount "$mountpoint"
    rmdir "$mountpoint"
    bootdone samizdat-nbd-dev

  else
    umount=true
    # Device has an unencrypted filesystem on it.
    # So we mount it and look for loop-back overlays.

    if [ -d "$mountpoint/samizdat.gpg" ]; then
      # check the key somehow?
      addmenu_choosekey "$DEVNAME" "$mountpoint/samizdat.gpg"
    fi

    N=1; while [ -e "$mountpoint/samizdat.$N" ]
    do
      if gpg_verify "$mountpoint/samizdat.$N"k; then
        addmenu_chooseroot "$DEVNAME" "$mountpoint/samizdat.$N"
        # this menu entry chooses the root fs, and should prompt and wait for the matching key
        umount=false
      fi
      N=$((N+1))
    done

    freeblocks=$(stat -f -c %f "$mountpoint")
    blocksize=$(stat -f -c %S "$mountpoint")
    freemegs=$((freeblocks * blocksize / 1024 / 1024))

    if [ "$freemegs" -ge 300 ]; then

      umount=false
      # bootwait samizdat-cdrom
      # cdromblocks=$(stat -f -c %b /cdrom)
      # cdromblocksize=$(stat -f -c %S /cdrom)
      # cdrommegs=$((cdromblocks * cdromblocksize / 1024 / 1024))

      cdrommegs=700 # TODO: go back to checking the size

      if [ "$freemegs"   -ge "$((cdrommegs * 3))" ]; then
        addmenu_makeroot "$DEVNAME" "${mountpoint}/samizdat.$N" "$((cdrommegs * 3))" 1
      elif [ "$freemegs" -ge "$((cdrommegs * 2))" ]; then
        addmenu_makeroot "$DEVNAME" "${mountpoint}/samizdat.$N" "$((cdrommegs * 2))" 1
      elif [ "$freemegs" -ge "$cdrommegs" ]; then
        addmenu_makeroot "$DEVNAME" "${mountpoint}/samizdat.$N" "$((freemegs / 2))" 0
      else
        addmenu_makeroot "$DEVNAME" "${mountpoint}/samizdat.$N" 256 0
      fi
    fi

    if $umount; then
      umount "$mountpoint"
      rmdir "$mountpoint"
    fi
  fi
}

# Get me all them nice udev variables
eval "$(PATH=$PATH:/lib/udev vol_id "$DEVNAME" |
  sed "s/'/'\\\\''/; s/=\(.*\)/='\1'/"
)"

CDROM_ID_FS_UUID_ENC='73256269-4002-4e42-adbd-0e49ed1c7438'
CDROM_ID_FS_LABEL_ENC=$(sed 's/ /\\x20/g' /lib/samizdat/vol_id.txt)
if [ "$ID_FS_UUID_ENC"  = "$CDROM_ID_FS_UUID_ENC" -o \
     "$ID_FS_LABEL_ENC" = "$CDROM_ID_FS_LABEL_ENC" ]
then
  # Recognize and mount the Samizdat
  if ! mountpoint -q /cdrom; then
    mkdir -p /cdrom
    . mdadm-dup.sh
    dup_mount_cdrom "$DEVNAME" /cdrom && bootdone samizdat-cdrom
    if [ -e /cdrom/gnupghome ]; then
      # TODO: don't use first match
      mkdir -p /gpg/gnupghome
      cp /cdrom/gnupghome/* /gpg/gnupghome
      bootdone samizdat-gpg
    fi
  fi
else
  grok_block &
fi

# vim:set et sw=2: