Wireguard setup in Docker on Debian kernel meant for a simple personal VPN. There are currently 2 branches, stretch and buster. Use the branch that corresponds to your host machine if the kernel module install feature is going to be used.

This docker image and configuration is my simple version of a wireguard personal VPN, used for the goal of security over insecure (public) networks, not necessarily for Internet anonymity. The docker images uses debian stable, and the host OS must also use the debian stable kernel, since the image will build the wireguard kernel modules on first run. As such, the hosts /lib/modules directory also needs to be mounted to the container on the first run to install the module (see the Running section below). Thanks to activeeos/wireguard-docker for the general structure of the docker image. It is the same concept just built on Ubuntu 16.04.

In my use case, I'm running the wireguard docker image on a free-tier Google Cloud Platform debian virtual machine and connect to it with Android, Linux, and a GL-Inet router as clients.

If the wireguard kernel module is not already installed on the host system, use this first run command to install it:

docker run -it --rm --cap-add sys_module -v /lib/modules:/lib/modules cmulk/wireguard-docker:stretch install-module

docker run --cap-add net_admin --cap-add sys_module -v <config volume or host dir>:/etc/wireguard -p <externalport>:<dockerport>/udp cmulk/wireguard-docker:stretch

Example:

docker run --cap-add net_admin --cap-add sys_module -v wireguard_conf:/etc/wireguard -p 5555:5555/udp cmulk/wireguard-docker:stretch

This shortcut can be used to generate and display public/private key pairs to use for the server or clients

docker run -it --rm cmulk/wireguard-docker:stretch genkeys

Sample server configuration to go in /etc/wireguard:

[Interface]
Address = 192.168.20.1/24
PrivateKey = <server_private_key>
ListenPort = 5555

[Peer]
PublicKey = <client_public_key>
AllowedIPs = 192.168.20.2

Sample client configuration:

[Interface]
Address = 192.168.20.2/24
PrivateKey = <client_private_key>
ListenPort = 0 #needed for some clients to accept the config

[Peer]
PublicKey = <server_public_key>
Endpoint = <server_public_ip>:5555
AllowedIPs = 0.0.0.0/0,::/0 #makes sure ALL traffic routed through VPN
PersistentKeepalive = 25

• This Docker image also has a iptables NAT (MASQUERADE) rule already configured to make traffic through the VPN to the Internet work. This can be disabled by setting the environment varialbe IPTABLES_MASQ to 0.
• For some clients (a GL.inet router in my case) you may have trouble with HTTPS (SSL/TLS) due to the MTU on the VPN. Ping and HTTP work fine but HTTPS does not for some sites. This can be fixed with MSS Clamping. This is simply a checkbox in the OpenWRT Firewall settings interface.

Sample docker-compose.yml

version: "2"
services:
 vpn:
  image: cmulk/wireguard-docker:stretch
  volumes:
   - data:/etc/wireguard
  networks:
   - net
  ports:
   - 5555:5555/udp
  restart: unless-stopped
  cap_add:
   - NET_ADMIN
   - SYS_MODULE

networks:
  net:

volumes:
 data:
  driver: local

Since the images are already on Docker Hub, you only need to do this if you want to change something

git clone https://github.com/cmulk/wireguard-docker.git
cd wireguard-docker
git checkout stretch 
##OR##
git checkout buster

docker build -t wireguard:local .