Show pagesourceOld revisionsBacklinksBack to top × Table of Contents OpenVPN server Introduction Goals Command-line instructions 1. Preparation 2. Key management 3. Firewall 4. VPN service Testing Troubleshooting Notes OpenVPN server This article relies on the following: Accessing OpenWrt CLI Managing configurations Managing packages Managing services Introduction This how-to describes the method for setting up OpenVPN server on OpenWrt. Follow OpenVPN client for client setup and OpenVPN extras for additional tuning. Goals Encrypt your internet connection to enforce security and privacy. Prevent data leak and traffic spoofing on the client side. Bypass regional restrictions using commercial providers. Escape client side content filters and internet censorship. Access your LAN services remotely without port forwarding. Command-line instructions The instructions below have been tested with OpenWrt 21.02. Also appears to work with 22.03.0-rc6 in testing. If you wish to install OpenVPN server on a previous version of OpenWrt, please refer to an older revision of this article, to avoid tls-crypt generation errors. eg.forum post 1. Preparation Install the required packages. Specify the VPN server configuration parameters. # Install packages opkg update opkg install openvpn-openssl openvpn-easy-rsa # Configuration parameters # OVPN_POOL config any network are OK except your local network OVPN_DIR="/etc/openvpn" OVPN_PKI="/etc/easy-rsa/pki" OVPN_PORT="1194" OVPN_PROTO="udp" OVPN_POOL="192.168.8.0 255.255.255.0" OVPN_DNS="${OVPN_POOL%.* *}.1" OVPN_DOMAIN="$(uci get dhcp.@dnsmasq[0].domain)" # Fetch WAN IP address . /lib/functions/network.sh network_flush_cache network_find_wan NET_IF network_get_ipaddr NET_ADDR "${NET_IF}" OVPN_SERV="${NET_ADDR}" # Fetch FQDN from DDNS client NET_FQDN="$(uci -q get ddns.@service[0].lookup_host)" if [ -n "${NET_FQDN}" ] then OVPN_SERV="${NET_FQDN}" fi 2. Key management Use EasyRSA to manage the PKI. Utilize private key password protection if necessary. # Configuration parameters export EASYRSA_PKI="${OVPN_PKI}" export EASYRSA_REQ_CN="ovpnca" export EASYRSA_BATCH="1" export EASYRSA_CERT_EXPIRE="3650" # Increases the client cert expiry from the default of 825 days to match the CA expiry # Remove and re-initialize PKI directory easyrsa init-pki # Generate DH parameters easyrsa gen-dh # Create a new CA easyrsa build-ca nopass # Generate server keys and certificate easyrsa build-server-full server nopass openvpn --genkey tls-crypt-v2-server ${EASYRSA_PKI}/private/server.pem # Generate client keys and certificate easyrsa build-client-full client nopass openvpn --tls-crypt-v2 ${EASYRSA_PKI}/private/server.pem \ --genkey tls-crypt-v2-client ${EASYRSA_PKI}/private/client.pem 3. Firewall Consider VPN network as private. Assign VPN interface to LAN zone to minimize firewall setup. Allow access to VPN server from WAN zone. # Configure firewall uci rename firewall.@zone[0]="lan" uci rename firewall.@zone[1]="wan" uci del_list firewall.lan.device="tun+" uci add_list firewall.lan.device="tun+" uci -q delete firewall.ovpn uci set firewall.ovpn="rule" uci set firewall.ovpn.name="Allow-OpenVPN" uci set firewall.ovpn.src="wan" uci set firewall.ovpn.dest_port="${OVPN_PORT}" uci set firewall.ovpn.proto="${OVPN_PROTO}" uci set firewall.ovpn.target="ACCEPT" uci commit firewall /etc/init.d/firewall restart 4. VPN service Configure VPN service and generate client profiles. # Configure VPN service and generate client profiles umask go= OVPN_DH="$(cat ${OVPN_PKI}/dh.pem)" OVPN_CA="$(openssl x509 -in ${OVPN_PKI}/ca.crt)" ls ${OVPN_PKI}/issued \ | sed -e "s/\.\w*$//" \ | while read -r OVPN_ID do OVPN_TC="$(cat ${OVPN_PKI}/private/${OVPN_ID}.pem)" OVPN_KEY="$(cat ${OVPN_PKI}/private/${OVPN_ID}.key)" OVPN_CERT="$(openssl x509 -in ${OVPN_PKI}/issued/${OVPN_ID}.crt)" OVPN_EKU="$(echo "${OVPN_CERT}" | openssl x509 -noout -purpose)" case ${OVPN_EKU} in (*"SSL server : Yes"*) OVPN_CONF="${OVPN_DIR}/${OVPN_ID}.conf" cat << EOF > ${OVPN_CONF} ;; user nobody group nogroup dev tun port ${OVPN_PORT} proto ${OVPN_PROTO} server ${OVPN_POOL} topology subnet client-to-client keepalive 10 60 persist-tun persist-key push "dhcp-option DNS ${OVPN_DNS}" push "dhcp-option DOMAIN ${OVPN_DOMAIN}" push "redirect-gateway def1" push "persist-tun" push "persist-key" <dh> ${OVPN_DH} </dh> EOF (*"SSL client : Yes"*) OVPN_CONF="${OVPN_DIR}/${OVPN_ID}.ovpn" cat << EOF > ${OVPN_CONF} ;; user nobody group nogroup dev tun nobind client remote ${OVPN_SERV} ${OVPN_PORT} ${OVPN_PROTO} auth-nocache remote-cert-tls server EOF esac cat << EOF >> ${OVPN_CONF} <tls-crypt-v2> ${OVPN_TC} </tls-crypt-v2> <key> ${OVPN_KEY} </key> <cert> ${OVPN_CERT} </cert> <ca> ${OVPN_CA} </ca> EOF done /etc/init.d/openvpn restart ls ${OVPN_DIR}/*.ovpn Basic openvpn server configuration is now complete. Perform OpenWrt backup. Either extract client profile from the archive file, or use SCP to retrieve the /etc/openvpn/client.ovpn file from the router. Review/edit the IP address for the 'remote' line contained within the client.ovpn file. Import the client.ovpn profile into your clients. For an additional .ovpn after completing the above: Run this multi-client script. Now make a script consisting of the “Configuration parameters” of Part 1 above and all of Part 4 above and run it. Note that the “remote” line may be missing in the new ovpn (use the original as a reference for that). Testing Establish the VPN connection. Use traceroute and traceroute6 to verify your client traffic is routed via the VPN gateway. traceroute openwrt.org traceroute6 openwrt.org Check your client public IP addresses. https://ipleak.net/ Make sure there is no DNS leak on the client side. https://dnsleaktest.com/ Delegate a public IPv6 prefix to the VPN network to use IPv6 by default. Troubleshooting Collect and analyze the following information. # Restart services /etc/init.d/log restart; /etc/init.d/openvpn restart; sleep 10 # Log and status logread -e openvpn; netstat -l -n -p | grep -e openvpn # Runtime configuration pgrep -f -a openvpn ip address show; ip route show table all ip rule show; iptables-save -c ip -6 rule show; ip6tables-save -c # Persistent configuration uci show network; uci show firewall; uci show openvpn head -v -n -0 /etc/openvpn/*.conf Notes For beginners to OpenVPN server, this PDF guide may be helpful. It is based on above cli instructions with additional note and tips. OpenVPN server setup guide for BT Home Hub 5A This website uses cookies. By using the website, you agree with storing cookies on your computer. Also you acknowledge that you have read and understand our Privacy Policy. If you do not agree leave the website.OKMore information about cookies Last modified: 2022/08/08 23:32by bill888