#!/bin/bash
# SPDX-License-Identifier: GPL-2.0
# Copyright (C) 2020-2025 OpenVPN, Inc.
#
#  Author:	Antonio Quartulli <antonio@openvpn.net>

UDP_PEERS_FILE=${UDP_PEERS_FILE:-udp_peers.txt}
TCP_PEERS_FILE=${TCP_PEERS_FILE:-tcp_peers.txt}
OVPN_CLI=${OVPN_CLI:-./ovpn-cli}
ALG=${ALG:-aes}
PROTO=${PROTO:-UDP}
FLOAT=${FLOAT:-0}

LAN_IP="11.11.11.11"

create_ns() {
	ip netns add peer${1}
}

setup_ns() {
	MODE="P2P"

	if [ ${1} -eq 0 ]; then
		MODE="MP"
		for p in $(seq 1 ${NUM_PEERS}); do
			ip link add veth${p} netns peer0 type veth peer name veth${p} netns peer${p}

			ip -n peer0 addr add 10.10.${p}.1/24 dev veth${p}
			ip -n peer0 addr add fd00:0:0:${p}::1/64 dev veth${p}
			ip -n peer0 link set veth${p} up

			ip -n peer${p} addr add 10.10.${p}.2/24 dev veth${p}
			ip -n peer${p} addr add fd00:0:0:${p}::2/64 dev veth${p}
			ip -n peer${p} link set veth${p} up
		done
	fi

	ip netns exec peer${1} ${OVPN_CLI} new_iface tun${1} $MODE
	ip -n peer${1} addr add ${2} dev tun${1}
	# add a secondary IP to peer 1, to test a LAN behind a client
	if [ ${1} -eq 1 -a -n "${LAN_IP}" ]; then
		ip -n peer${1} addr add ${LAN_IP} dev tun${1}
		ip -n peer0 route add ${LAN_IP} via $(echo ${2} |sed -e s'!/.*!!') dev tun0
	fi
	if [ -n "${3}" ]; then
		ip -n peer${1} link set mtu ${3} dev tun${1}
	fi
	ip -n peer${1} link set tun${1} up
}

add_peer() {
	if [ "${PROTO}" == "UDP" ]; then
		if [ ${1} -eq 0 ]; then
			ip netns exec peer0 ${OVPN_CLI} new_multi_peer tun0 1 ${UDP_PEERS_FILE}

			for p in $(seq 1 ${NUM_PEERS}); do
				ip netns exec peer0 ${OVPN_CLI} new_key tun0 ${p} 1 0 ${ALG} 0 \
					data64.key
			done
		else
			RADDR=$(awk "NR == ${1} {print \$2}" ${UDP_PEERS_FILE})
			RPORT=$(awk "NR == ${1} {print \$3}" ${UDP_PEERS_FILE})
			LPORT=$(awk "NR == ${1} {print \$5}" ${UDP_PEERS_FILE})
			ip netns exec peer${1} ${OVPN_CLI} new_peer tun${1} ${1} ${LPORT} \
				${RADDR} ${RPORT}
			ip netns exec peer${1} ${OVPN_CLI} new_key tun${1} ${1} 1 0 ${ALG} 1 \
				data64.key
		fi
	else
		if [ ${1} -eq 0 ]; then
			(ip netns exec peer0 ${OVPN_CLI} listen tun0 1 ${TCP_PEERS_FILE} && {
				for p in $(seq 1 ${NUM_PEERS}); do
					ip netns exec peer0 ${OVPN_CLI} new_key tun0 ${p} 1 0 \
						${ALG} 0 data64.key
				done
			}) &
			sleep 5
		else
			ip netns exec peer${1} ${OVPN_CLI} connect tun${1} ${1} 10.10.${1}.1 1 \
				data64.key
		fi
	fi
}

cleanup() {
	# some ovpn-cli processes sleep in background so they need manual poking
	killall $(basename ${OVPN_CLI}) 2>/dev/null || true

	# netns peer0 is deleted without erasing ifaces first
	for p in $(seq 1 10); do
		ip -n peer${p} link set tun${p} down 2>/dev/null || true
		ip netns exec peer${p} ${OVPN_CLI} del_iface tun${p} 2>/dev/null || true
	done
	for p in $(seq 1 10); do
		ip -n peer0 link del veth${p} 2>/dev/null || true
	done
	for p in $(seq 0 10); do
		ip netns del peer${p} 2>/dev/null || true
	done
}

if [ "${PROTO}" == "UDP" ]; then
	NUM_PEERS=${NUM_PEERS:-$(wc -l ${UDP_PEERS_FILE} | awk '{print $1}')}
else
	NUM_PEERS=${NUM_PEERS:-$(wc -l ${TCP_PEERS_FILE} | awk '{print $1}')}
fi