mdw@git.distorted.org.uk Git - distorted-keys/blob - keys.new-recov

   1 #! /bin/sh
   2 ###
   3 ### Generate a new recovery key and split it among keepers
   4 ###
   5 ### (c) 2011 Mark Wooding
   6 ###
   7
   8 ###----- Licensing notice ---------------------------------------------------
   9 ###
  10 ### This file is part of the distorted.org.uk key management suite.
  11 ###
  12 ### distorted-keys is free software; you can redistribute it and/or modify
  13 ### it under the terms of the GNU General Public License as published by
  14 ### the Free Software Foundation; either version 2 of the License, or
  15 ### (at your option) any later version.
  16 ###
  17 ### distorted-keys is distributed in the hope that it will be useful,
  18 ### but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 ### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 ### GNU General Public License for more details.
  21 ###
  22 ### You should have received a copy of the GNU General Public License
  23 ### along with distorted-keys; if not, write to the Free Software Foundation,
  24 ### Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  25
  26 set -e
  27 case "${KEYSLIB+t}" in t) ;; *) echo >&2 "$0: KEYSLIB unset"; exit 1 ;; esac
  28 . "$KEYSLIB"/keyfunc.sh
  29
  30 defhelp <<HELP
  31 [-p PROFILE] RECOV [KEEPER:K ...] [-- OPTION=VALUE ...]
  32 Generate a new recovery secret, and split it among the available keepers.
  33
  34 The new secret will be called RECOV.  For each KEEPER set, the private key
  35 wil be split into shares, and encrypted with the KEEPER's public keys; any K
  36 of these shares can be used to reveal the original key.
  37
  38 If there is already a recovery key called RECOV then it will be rolled over.
  39 The previous key must already be revealed.  If KEEPERs are listed, these
  40 replace the existing keeper sets; otherwise the same keepers as before are
  41 used.
  42
  43 If there is not a recovery key called RECOV then at least one keeper set must
  44 be specified.
  45 HELP
  46
  47 ## Parse the command line.
  48 profile=${recov_profile-recovery}
  49 while getopts "p:" opt; do
  50   case "$opt" in
  51     p) profile=$OPTARG ;;
  52     *) usage_err ;;
  53   esac
  54 done
  55 shift $(( $OPTIND - 1 ))
  56 case $# in 0) usage_err ;; esac
  57 recov=$1; shift
  58 checkword "recovery key label" "$recov"
  59 checkword "profile label" "$profile"
  60 nkeep=0
  61 for k in "$@"; do
  62   case "$k" in
  63     --) break ;;
  64     *:*) ;;
  65     *) echo >&2 "$quis: bad keeper spec \`$k'"; exit 1 ;;
  66   esac
  67   keeper=${k%:*} t=${k#*:} nkeep=$(( $nkeep + 1 ))
  68   checkword "keeper set label" "$keeper"
  69   checknumber "keeper quorum" "$t"
  70 done
  71
  72 ## Establish the keeper parameters.
  73 rdir=$KEYS/recov/$recov
  74 if [ ! -d $rdir ]; then mkdir -m755 -p $rdir; fi
  75 case $nkeep in
  76   0)
  77     kparam=$rdir/keepers
  78     ;;
  79   *)
  80     for k in "$@"; do
  81       case "$k" in --) break ;; esac
  82       keeper=${k%:*} t=${k#*:}
  83       echo $keeper $t
  84     done >$rdir/keepers.new
  85     kparam=$rdir/keepers.new
  86     ;;
  87 esac
  88 if [ ! -f $kparam ]; then echo >&2 "$quis: no keepers specified"; exit 1; fi
  89
  90 ## Make the new key and issue the shares.
  91 mktmp
  92 rm -rf $rdir/new
  93 mkdir -m755 $rdir/new
  94 cd $tmp
  95 while :; do case "$#,$1" in
  96     0,) break ;;
  97     *,*,*) ;;
  98     *,--) break ;;
  99   esac
 100   shift
 101 done
 102 c_gensyskey $profile $rdir/new/store secret recov="$recov"
 103 while read keeper k; do
 104   read n hunoz <$KEYS/keeper/$keeper/meta
 105   $bindir/shamir issue $k/$n secret | {
 106     read param
 107     echo "$param" >$rdir/new/$keeper.param
 108     i=0
 109     while read share; do
 110       c_sysencrypt $KEYS/keeper/$keeper/$i >$rdir/new/$keeper.$i.share <<EOF
 111 $share
 112 EOF
 113       i=$(( $i + 1 ))
 114     done
 115   }
 116 done <$kparam
 117 rm -f secret
 118
 119 ## If there's an existing instance of this key, transfer the recovery blobs.
 120 if [ ! -d $rdir/current ]; then
 121   seq=0
 122 else
 123   seq=$(readlink $rdir/current)
 124   reqsafe
 125   reveal=$SAFE/keys.reveal/$recov.current/secret
 126   if [ ! -f $reveal ]; then
 127     echo >&2 "$quis: current $recov key not revealed"
 128     exit 1
 129   fi
 130
 131   find $rdir/current/ -type f -name '*.recov' -print | while read name; do
 132     name=${name#$rdir/current/}
 133     case "$name" in */*) mkdir -p -m755 $rdir/new/${name%/*} ;; esac
 134     c_sysdecrypt $rdir/current/store $reveal <$rdir/current/$name >tmp
 135     c_sysencrypt $rdir/new/store <tmp >$rdir/new/$name
 136     rm tmp
 137   done
 138   rm -r $SAFE/keys.reveal/$recov.current
 139 fi
 140
 141 ## Tidy up and commit.  Repointing the symlink is grim because, according to
 142 ## POSIX rules, `mv foo bar' should rename `foo' to `bar/foo' is `bar' is a
 143 ## symlink to a directory -- and there's no way of turning this behaviour
 144 ## off.  The subterfuge here is due to Colin Watson.
 145 cd $rdir
 146 while [ -d $seq ]; do seq=$(( $seq + 1 )); done
 147 case $kparam in *.new) mv keepers.new keepers ;; esac
 148 rm -f next
 149 ln -s $seq next
 150 mv new $seq
 151 mkdir hack; mv next hack/current; mv hack/current .; rmdir hack
 152
 153 ###----- That's all, folks --------------------------------------------------