#!/bin/bash

CERTFILE="/etc/lighttpd/server.pem"
CHAINFILE="/etc/lighttpd/chain.pem"

op_disable ()
{
	[ -e "$CERTFILE" ] || exit 0
	rm -f -- "$CERTFILE" || exit 1
	rm -f -- "$CHAINFILE"
}

op_test ()
{
	[ $# -eq 2 ] || exit 1
	local K=$1
	local C=$2
	[ -r "$K" ] || exit 2
	[ -r "$C" ] || exit 3
	# Encrypt something, then decrypt again and compare
	local TEST_IN=$(mktemp --tmpdir bwlp-XXXXXXXX)
	local TEST_OUT=$(mktemp --tmpdir bwlp-XXXXXXXX)
	local TEST_DIFF=$(mktemp --tmpdir bwlp-XXXXXXXX)
	[ -z "$TEST_IN" ] && exit 4
	[ -z "$TEST_OUT" ] && exit 5
	[ -z "$TEST_DIFF" ] && exit 6
	date > "$TEST_IN"
	openssl smime -encrypt -binary -aes-256-cbc -in "$TEST_IN" -out "$TEST_OUT" -outform DER "$C" || exit 7
	openssl smime -decrypt -binary -in "$TEST_OUT" -inform DER -out "$TEST_DIFF" -inkey "$K" || exit 8
	diff -q "$TEST_IN" "$TEST_DIFF" || exit 9
	exit 0 # No restart either way
}

op_import ()
{
	[ $# -lt 2 ] && exit 1
	local K=$1
	local C=$2
	local CHAIN=$3
	[ -r "$K" ] || exit 2
	[ -r "$C" ] || exit 3
	rm -f -- "$CHAINFILE"
	# Create server.pem
	cat "$C" "$K" > "$CERTFILE"
	chmod 0600 "$CERTFILE" || exit 4
	rm -f -- "$C" "$K"
	# If we have a chainfile, try to use it aswell
	if [ -s "$CHAIN" ]; then
		openssl x509 -noout -hash -in "$CHAIN" >/dev/null 2>&1 && cp "$CHAIN" "$CHAINFILE"
	fi
	generate_dh
	return 0
}

op_random ()
{
	[ -z "$1" ] && exit 1
	rm -f -- "$CHAINFILE"
	openssl req -x509 -new -newkey rsa:4096 -keyout "$CERTFILE" -out "$CERTFILE" -days 5000 -nodes -subj "/C=DE/ST=Nowhere/L=Springfield/O=bwLehrpool/CN=$1" || exit 2
	chmod 0600 "$CERTFILE" || exit 3
	generate_dh
	return 0
}

generate_dh ()
{
	local DHPARAM="/etc/lighttpd/dhparam.pem"
	if ! [ -s "$DHPARAM" ]; then
		echo "Generating DH parameters (this takes a while)..."
		if openssl dhparam -out "$DHPARAM" 2048 >/dev/null 2>&1; then
			echo "done"
		else
			echo "failed"
			rm -f -- "$DHPARAM"
		fi
	fi
}

OP=$1
shift

case "$OP" in
	--random) op_random "$@" ;;
	--test) op_test "$@" ;;
	--import) op_import "$@" ;;
	--disable) op_disable ;;
	*)
		echo "Invalid operation: $1"
		exit 1
		;;
esac

systemctl restart lighttpd

exit 0