#!/bin/sh

# jsaccess - private web file sharing using client side crypto
# store.sh: file encrytion script

# Copyright (c) 2013 Laurent Ghigonis <laurent@gouloum.fr>
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

cleanup() {
	rm -f $tmp
	umask $sumask
	exit 0
}

if [ $# -ne 1 ]; then
	echo "usage: store.sh <file_to_share>"
	exit 1
fi
clear_path=$1
clear_name=`basename $clear_path`

# Check for dependencies
if [ X"`which base64`" == X"" \
	-o X"`which openssl`" == X"" ]; then
	echo "You need to have openssl and base64 available in your path !"
	exit 1
fi

# Initialize temporary stuff
sumask=$(umask)
umask 077
tmp=`mktemp ./jsaXXXXXXXX`
trap cleanup INT TERM EXIT

# Read passphrase
echo -n "Enter encryption passphrase: "
read pass

# Generate file/directory names
enc_dir_hash=`echo -n $pass |openssl rmd160 |cut -d' ' -f2`
enc_path="jsa/files/$enc_dir_hash"
enc_name=`echo -n ${enc_dir_hash}${clear_name} |openssl rmd160 |cut -d' ' -f2`
echo $enc_path
mkdir -p $enc_path
touch $enc_path/index.html

# Encrypt file
base64 -w0 $clear_path > $tmp
echo -n $pass |openssl enc -e -a -aes-256-cbc -in $tmp -out $enc_path/$enc_name -pass stdin ||exit $?
echo "CREATED $enc_path/$enc_name"

# Add to passphrase index
if [ -f $enc_path/index.txt ]; then
	echo -n $pass |openssl enc -d -a -aes-256-cbc -in $enc_path/index.txt -out $tmp -pass stdin ||exit $?
else
	echo > $tmp
fi
echo $clear_name >> $tmp
rm -f $enc_path/index.txt
echo -n $pass |openssl enc -e -a -aes-256-cbc -in $tmp -out $enc_path/index.txt -pass stdin ||exit $?
echo "UPDATED $enc_path/index.txt"