RSA Encryption

rsacrypt.sh

#!/bin/sh
# openssl rsa -in ~/.ssh/id_rsa -pubout -out ~/.ssh/id_rsa.pub.pem
# ln -s ~/rsacrypt.sh /usr/bin/rsacrypt

ENCRYPTED=""
DECRYPTED=""

usage() {
	echo -e "\nUsage: $0 [-e [PUBLIC_KEY]] [-d [PRIVATE_KEY]]"
	exit 1
}

while getopts ":d:e:" opt; do
	[ "$OPTARG$opt" == "d:" ] && opt="d" && OPTARG=~/.ssh/id_rsa
	[ "$OPTARG$opt" == "e:" ] && opt="e" && OPTARG=~/.ssh/id_rsa.pub.pem
	case $opt in
		e)
			if [ -z "$DECRYPTED" ]; then
				echo -e "\nEnter your decrypted content (end with ESC): "
				read -d $(echo -e "\e") DECRYPTED
				echo -e "\n"
			fi
			echo -e "\nEncrypted data for ${OPTARG##*/}:\n"
			echo "$DECRYPTED" | openssl rsautl -inkey $OPTARG -pubin -encrypt | openssl base64
		;;
		d)
			if [ -z "$ENCRYPTED" ]; then
				echo -e "\nEnter your encrypted content (end with ESC): "
				read -d $(echo -e "\e") ENCRYPTED
				echo -e "\n"
			fi
			DECRYPTED=$(echo "$ENCRYPTED" | openssl base64 -d | openssl rsautl -inkey $OPTARG -decrypt)
			echo -e "\nDecrypted with ${OPTARG##*/}:\n$DECRYPTED"
		;;
		f)
			#if [ -n "$DECRYPTED" ]
	esac
done

[ -z "$ENCRYPTED$DECRYPTED" ] && usage