#! /bin/sh
###
### Recover a user key nub
###
### (c) 2011 Mark Wooding
###

###----- Licensing notice ---------------------------------------------------
###
### This file is part of the distorted.org.uk key management suite.
###
### distorted-keys is free software; you can redistribute it and/or modify
### it under the terms of the GNU General Public License as published by
### the Free Software Foundation; either version 2 of the License, or
### (at your option) any later version.
###
### distorted-keys is distributed in the hope that it will be useful,
### but WITHOUT ANY WARRANTY; without even the implied warranty of
### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
### GNU General Public License for more details.
###
### You should have received a copy of the GNU General Public License
### along with distorted-keys; if not, write to the Free Software Foundation,
### Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.

set -e
case "${KEYSLIB+t}" in t) ;; *) echo >&2 "$0: KEYSLIB unset"; exit 1 ;; esac
. "$KEYSLIB"/keyfunc.sh

defhelp <<HELP
KEY RECOV
Recover the named user KEY using a blob protected using the recovery key
RECOV; it is an error if RECOV is not currently revealed.
HELP

case $# in 2) ;; *) usage_err ;; esac
key=$1 recov=$2
parse_keylabel "$key"
if [ ! -d $kdir ]; then echo >&2 "$quis: unknown key \`$key'"; exit 1; fi
checkword "recovery key label" "$recov"
case $kowner in
  $USERV_USER) ;;
  *) echo >&2 "$quis: you're not the owner of key \`$key'"; exit 1 ;;
esac

mktmp
nubid=$(cat $kdir/nubid)
readmeta $kdir
read_profile $kowner "$profile"
if [ -f $knub ]; then
  nubbin=$(nubid <$knub)
  case "$nubbin" in
    "$nubid")
      echo >&2 "$quis: key \`$key' doesn't need recovery"
      exit 1
      ;;
  esac
fi

umask 077
recover $recov $kowner/$klabel >$knub.new
nubbin=$(nubid <$knub.new)
case "$nubbin" in
  "$nubid") ;;
  *)
    echo >&2 "$quis: recovery produced incorrect nub"
    exit 1
    ;;
esac
mv $knub.new $knub

###----- That's all, folks --------------------------------------------------