Simple CLI file encrypter/decrypter with GPG

aes.sh

#!/bin/bash

mode=""
filename=""

# http://stackoverflow.com/a/7069755

while test $# -gt 0; do
	case "$1" in
		-h|--help)
			echo "Usage: aes.sh -e|d <filename>"
			exit 0
			;;
		-e|--encrypt)
			mode="e"
			shift
			;;
		-d|--decrypt)
			mode="d"
			shift
			;;
		-|--*)
			echo "Unknown flag: $1"
			exit 1
			;;
		*)
			if [ -f $1 ]; then
				filename="$1"
				shift
			else
				echo "File \"$1\" does not exist."
				exit 1
			fi
			;;
	esac
done

# echo "mode=$mode file=$filename"

if [ -z $mode ]; then
	echo "No mode flag specified."
	exit 1
elif [ -z $filename ]; then
	echo "No file specified."
	exit 1
fi

# http://stackoverflow.com/a/31552829
# http://stackoverflow.com/q/12152626

if [ "$mode" = "e" ]; then
	gpg --output $filename.aes --symmetric --cipher-algo AES256 $filename
elif [ "$mode" = "d" ]; then
	gpg --output $(basename $filename .aes) --decrypt $filename
fi

# To be prompted for a password sooner when decrypting a file:
# In Settings -> Configure Kleopatra -> GnuPG System -> GPG agent
# I changed "Expire cached PINs after N seconds" to 60 s.

# or uncomment:

# gpgconf --reload gpg-agent