#!/bin/bash

KEYFILE=.encryption_key
KEYFILE=$HOME/$KEYFILE

if [ $# -eq 0 ]
  then
    echo "Encrypt a file using a keyfile at $KEYFILE and store it to <filename>.enc.txt."
    echo "Usage: $0 <filename>".
    exit 1;
fi


if [ ! -f "$KEYFILE" ]; then
    echo "$KEYFILE does not exist. Please create that first with the encryption key you want to use."
    exit 1
fi

PASSWORD=$(cat "$KEYFILE")
INPUT_FILE=$1

openssl aes-256-cbc -md sha256 -salt -a -in ${INPUT_FILE} -out ${INPUT_FILE}.enc.txt -pass pass:${PASSWORD}
echo "Encrypted '$INPUT_FILE' using the key at '$KEYFILE'."
echo "Wrote output to '${INPUT_FILE}.enc.txt'.";