mdw@git.distorted.org.uk Git - distorted-keys/blob - 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 program is free software; you can redistribute it and/or modify
  11 ### it under the terms of the GNU General Public License as published by
  12 ### the Free Software Foundation; either version 2 of the License, or
  13 ### (at your option) any later version.
  14 ###
  15 ### This program is distributed in the hope that it will be useful,
  16 ### but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ### GNU General Public License for more details.
  19 ###
  20 ### You should have received a copy of the GNU General Public License
  21 ### along with this program; if not, write to the Free Software Foundation,
  22 ### Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  23
  24 set -e
  25 case "${KEYSLIB+t}" in t) ;; *) echo >&2 "$0: KEYSLIB unset"; exit 1 ;; esac
  26 . "$KEYSLIB"/keyfunc.sh
  27
  28 defhelp <<HELP
  29 RECOV [KEEPER:K ...]
  30 Generate a new recovery secret, and split it among the available keepers.
  31
  32 The new secret will be called RECOV.  For each KEEPER set, the private key
  33 wil be split into shares, and encrypted with the KEEPER's public keys; any K
  34 of these shares can be used to reveal the original key.
  35
  36 If there is already a recovery key called RECOV then it will be rolled over.
  37 The previous key must already be revealed.  If KEEPERs are listed, these
  38 replace the existing keeper sets; otherwise the same keepers as before are
  39 used.
  40
  41 If there is not a recovery key called RECOV then at least one keeper set must
  42 be specified.
  43 HELP
  44 dohelp
  45
  46 ## Parse the command line.
  47 case $# in 0) echo >&2 "$usage"; exit 1 ;; esac
  48 recov=$1; shift
  49 checkword "recovery key label" "$recov"
  50 for k in "$@"; do
  51   case "$k" in
  52     *:*) ;;
  53     *) echo >&2 "$quis: bad keeper spec \`$k'"; exit 1 ;;
  54   esac
  55   keeper=${k%:*} t=${k#*:}
  56   checkword "keeper set label" "$keeper"
  57   checknumber "keeper quorum" "$t"
  58 done
  59
  60 ## Establish the keeper parameters.
  61 rdir=$KEYS/recov/$recov
  62 if [ ! -d $rdir ]; then mkdir -m755 -p $rdir; fi
  63 case $# in
  64   0)
  65     kparam=$rdir/keepers
  66     ;;
  67   *)
  68     for k in "$@"; do
  69       keeper=${k%:*} t=${k#*:}
  70       echo $keeper $t
  71     done >$rdir/keepers.new
  72     kparam=$rdir/keepers.new
  73     ;;
  74 esac
  75 if [ ! -f $kparam ]; then echo >&2 "$quis: no keepers specified"; exit 1; fi
  76
  77 ## Make the new key and issue the shares.
  78 tmp=$(mktmp); cleanup rmtmp
  79 rm -rf $rdir/new
  80 mkdir -m755 $rdir/new
  81 cd $tmp
  82 ec_keygen secret $rdir/new/pub
  83 while read keeper k; do
  84   read n hunoz <$KEYS/keeper/$keeper/meta
  85   shamir issue $k/$n secret | {
  86     read param
  87     echo "$param" >$rdir/new/$keeper.param
  88     i=0
  89     while read share; do
  90       echo $share |
  91         ec_encrypt $KEYS/keeper/$keeper/$i.pub -o$rdir/new/$keeper.$i.share
  92       i=$(( i + 1 ))
  93     done
  94   }
  95 done <$kparam
  96 rm -f secret
  97
  98 ## If there's an existing instance of this key, transfer the recovery blobs.
  99 if [ ! -d $rdir/current ]; then
 100   seq=0
 101 else
 102   seq=$(readlink $rdir/current)
 103   mem=$(userv root claim-mem-dir)
 104   reveal=$mem/keys.reveal.$recov.current/secret
 105   if [ ! -f $reveal ]; then
 106     echo >&2 "$quis: current $recov key not revealed"
 107     exit 1
 108   fi
 109   find $rdir/current -type f -name '*.recov' -print | while read name; do
 110     name=${name#$rdir/current/}
 111     case "$name" in */*) mkdir -p -m755 $rdir/new/${name%/*} ;; esac
 112     ec_decrypt $reveal -i$rdir/current/$name |
 113       ec_encrypt $rdir/new/pub -o$rdir/new/$name
 114   done
 115 fi
 116
 117 ## Tidy up and commit.
 118 cd $rdir
 119 while [ -d $seq ]; do seq=$(( seq + 1 )); done
 120 case $kparam in *.new) mv keepers.new keepers ;; esac
 121 rm -f next
 122 ln -s $seq next
 123 mv new $seq
 124 mv next current
 125
 126 ###----- That's all, folks --------------------------------------------------