#!/bin/bash
#
# $Id: remote-ssh-gpg-backup,v 1.1 2003/10/25 12:23:13 suter Exp $
# Copyright (C) 2003 Mark Suter <mark.suter@miju.com.au>
#
# This program 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.
#
# This program 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 this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

## Our "die" function (think perl)
function die () { echo "$@" 1>&2 ; exit 1 ; }

## Set our PATH and test for needed binaries
export PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
hash test md5sum find cpio gpg ssh || die $0: required binaries not present

## Get the passphrase and check it against the md5sum we have stored
echo -n "Passphrase: "
read -s passphrase
test "$(echo $passphrase | md5sum)" == "dd02c7c2232759874e1c205587017bed  -" || die $0: passphrase does not match md5sum
echo ok.

## The Heart of the Script - please customise to your needs
find /path/to/backup -print0 | \
    cpio --null --format=crc --create | \
    gpg --no-use-agent --passphrase-fd 3 --batch --quiet --symmetric 3< <(echo "$passphrase") | \
    ssh remote.example.org cat \> backup.cpio