mdw@git.distorted.org.uk Git - udpkey/blob - debian/udpkey.keyscript

   1 #! /bin/sh
   2 ### udpkey.keyscript KEY/SERVER:PORT[=TAG][#HASH];...
   3 ###
   4 ### This is an example cryptsetup key-script for fetching keys during early
   5 ### boot.  The argument is obtained as the `key-file' field from the
   6 ### crypttab(5) file.  The KEY is the key tag name requested from the
   7 ### server(s); the rest of the argument is a udpkey(1) source-spec.
   8 ###
   9 ### A hook script or similar should arrange for /usr/bin/udpkey to be
  10 ### installed and for the following things to be placed in /etc/udpkey in the
  11 ### initramfs.  See udpkey.initramfs-hook for an example.
  12 ###
  13 ### keyring     The keyring file used by udpkey.
  14 ###
  15 ### KEY.local   A locally held key fragment.  (Optional.)
  16 ###
  17 ### seed        A key for udpkey's random-number generator.  Ideally, a hook
  18 ###             script should write high-quality random data to this file
  19 ###             each time the initramfs is constructed.
  20 ###
  21 ### The generated initramfs will contain important secrets.  It must not be
  22 ### left readable by unprivileged users.
  23
  24 set -e
  25
  26 ## Check the command-line argument.
  27 case $#,$1 in
  28   1,*/*:*) tag=${1%%/*} server=${1#*/} ;;
  29   *) echo >&2 "Usage: $0 KEY/SERVER:PORT[=TAG][#HASH];..."; exit 16 ;;
  30 esac
  31
  32 ## Some preflight checks.
  33 if [ ! -x /usr/bin/udpkey ]; then
  34   echo >&2 "$0: can't find udpkey executable"
  35   exit 8
  36 fi
  37 if [ ! -f /etc/udpkey/keyring ]; then
  38   echo >&2 "$0: can't find local keyring"
  39   exit 8
  40 fi
  41
  42 ## Make sure we have networking.
  43 if [ -f /scripts/functions ]; then
  44   . /scripts/functions
  45   configure_networking
  46 fi
  47
  48 ## Build a command line.
  49 cmd="/usr/bin/udpkey -k/etc/udpkey/keyring"
  50 if [ -f /etc/udpkey/seed ]; then
  51   cmd="$cmd -r/etc/udpkey/seed"
  52 fi
  53 cmd="$cmd $tag $server"
  54 if [ -f /etc/udpkey/$tag.local ]; then
  55   cmd="$cmd /etc/udpkey/$tag.local"
  56 fi
  57
  58 ## Ready to rock.
  59 exec $cmd