/encryptCalcurse.sh

  1#!/bin/bash
  2
  3# ENCRYPTCALCURSE.SH
  4
  5# Written by Oz Nahum <nahumoz__at_you_know_where_no_spam_is_gmail.com>
  6# This script is distributed under the terms of the GNU Public License 
  7# Version 3 or later.
  8# You can obtaion copies of this license at:
  9# http://www.gnu.org/licenses/gpl.html
 10
 11# A script to decrypt the calcurse_date dir, open it in 
 12# /home/<user>/calcurse_data
 13# then launch calcurse pointing to it, 
 14# and upon closing calcurse, encrypt the data, move it to usb stick, 
 15# and delete all data from /home/<user>/calcurse_data
 16
 17### Begin of Script
 18
 19INPUT_FILE="calcurse_d.tar.enc"
 20OUTPUT_FILE="calcurse_d.tar.enc"
 21
 22#name of directory to encrypt (e.g. ~.calcurse)
 23CALCURSE_DATA_DIR="~/.calcurse/"
 24
 25# usage:
 26# $ bash encryptCalcurse.sh 
 27# $ bash encryptCalcurse.sh [ecnrypted_data_in.enc] [encrypted_data_out.enc]
 28
 29#TODO: test that modified script !
 30### Begin of Script
 31#make files readable only by owner
 32umask 077
 33
 34function Config {
 35    USB=`pwd`
 36    tar -cf calcurse_data.tar $CALCURSE_DATA_DIR
 37    openssl aes-256-cbc -salt -in calcurse_data.tar -out calcurse_d.tar.enc
 38    clc=`which calcurse`
 39    cp -v $clc $USB
 40    
 41}
 42
 43function cleanUp {
 44    find /dev/shm/calcurse_data -type f | xargs shred -fuz;
 45    if [ -f /dev/shm/cdt.tar ]; then
 46        shred -fuz /dev/shm/cdt.tar
 47    fi
 48    if [ -f /dev/shm/calcurse_data_tmp.tar ]; then
 49        shred -fuz /dev/shm/calcurse_data_tmp.tar
 50    fi
 51    rmdir /dev/shm/calcurse_data/notes
 52    rmdir /dev/shm/calcurse_data
 53}
 54
 55function readData {
 56#first decrypt the data
 57openssl enc -d -aes-256-cbc -salt -in $INPUT_FILE -out /dev/shm/calcurse_data_tmp.tar
 58echo "extracting data"
 59#silently extract data, no need for verbose output (v flag)
 60tar -C /dev/shm -xf /dev/shm/calcurse_data_tmp.tar
 61#note unpacking removes the original tar
 62}
 63
 64function encryptData {
 65openssl aes-256-cbc -salt -in /dev/shm/cdt.tar -out calcurse_d.tar.enc
 66}
 67
 68
 69case "$1" in
 70    "")
 71    echo "expecting parameter input... see header of script for usage"
 72    ;;
 73    "--config")
 74        CALCURSE_DATA_DIR=$2    
 75        Config
 76    ;;
 77
 78    "--read")
 79        trap "cleanUp" SIGHUP SIGINT SIGQUIT SIGKILL SIGABRT SIGTERM EXIT
 80        # when calcurse is done tar the direcotry
 81        readData
 82        calcurse -D /dev/shm/calcurse_data
 83        tar -cf /dev/shm/cdt.tar -C /dev/shm/ calcurse_data/
 84            
 85        # then encrypt
 86        # if encryption failed $? == 1 so repeat it again ...
 87        encryptData
 88        es=$?
 89        while [ "$es" = "1" ]; do 
 90            echo "encrypting data"
 91            encryptData
 92            es=$?    
 93        done
 94    ;;
 95    "--decrypt")
 96        readData
 97    ;;
 98    "--encrypt")
 99        tar -cvf /dev/shm/cdt.tar -C /dev/shm/ calcurse_data/
100        encryptData
101    ;;
102
103        #if encryption succeeded clean up by calling the function
104        #cleanUp
105    
106esac
107#note about the salt option note found in openssl man page[1],[2]
108#note about lack of compresion with ssl [3]
109
110#sources:
111#[1]http://ubuntuforums.org/showpost.php?p=8287351&postcount=9
112#[2]http://linux.die.net/man/1/enc
113#[3]http://serverfault.com/questions/17855/can-i-compr:ess-an-encrypted-file