This repository is quite old, and it's likely that there are better alternatives these days. The original author (@jpetazzo) is not maintaining it anymore, and cannot provide help or support with it. That being said, if you feel brave, feel free to try it; but keep in mind that it hasn't received significant updates since 2016.
Thank you!
Quick instructions:
CID=$(docker run -d --privileged -p 1194:1194/udp -p 443:443/tcp jpetazzo/dockvpn)
docker run -t -i -p 8080:8080 --volumes-from $CID jpetazzo/dockvpn serveconfigNow download the file located at the indicated URL. You will get a
certificate warning, since the connection is done over SSL, but we are
using a self-signed certificate. After downloading the configuration,
stop the serveconfig container. You can restart it later if you need
to re-download the configuration, or to download it to multiple devices.
The file can be used immediately as an OpenVPN profile. It embeds all the required configuration and credentials. It has been tested successfully on Linux, Windows, and Android/iOS clients.
Note: there is a bug in the Android Download Manager which prevents downloading files from untrusted SSL servers; and in that case, our self-signed certificate means that our server is untrusted. If you try to download with the default browser on your Android device, it will show the download as "in progress" but it will remain stuck. You can download it with Firefox; or you can transfer it with another way: Dropbox, USB, micro-SD card...
If you reboot the server (or stop the container) and you docker run
again, you will create a new service (with a new configuration) and
you will have to re-download the configuration file. However, you can
use docker start to restart the service without touching the configuration.
When the jpetazzo/dockvpn image is started, it generates:
- Diffie-Hellman parameters,
- a private key,
- a self-certificate matching the private key,
- two OpenVPN server configurations (for UDP and TCP),
- an OpenVPN client profile.
Then, it starts two OpenVPN server processes (one on 1194/udp, another on 443/tcp).
The configuration is located in /etc/openvpn, and the Dockerfile
declares that directory as a volume. It means that you can start another
container with the --volumes-from flag, and access the configuration.
Conveniently, jpetazzo/dockvpn comes with a script called serveconfig,
which starts a pseudo HTTPS server on 8080/tcp. The pseudo server
does not even check the HTTP request; it just sends the HTTP status line,
headers, and body right away.
We use tun mode, because it works on the widest range of devices.
tap mode, for instance, does not work on Android, except if the device
is rooted.
The topology used is net30, because it works on the widest range of OS.
p2p, for instance, does not work on Windows.
The TCP server uses 192.168.255.0/25 and the UDP server uses
192.168.255.128/25. However, you can change these subnets by
setting the SUBNET environment variable. Note that at the moment,
you can only specify the first three octets of the subnet, and
the TCP and UDP servers will use the lower /25 and upper /25
subnets respectively.
For instance, you can do:
docker run -d --privileged -p 1194:1194/udp -p 443:443/tcp \
-e SUBNET=192.168.13 jpetazzo/dockvpnThe client profile specifies redirect-gateway def1, meaning that after
establishing the VPN connection, all traffic will go through the VPN.
This might cause problems if you use local DNS recursors which are not
directly reachable, since you will try to reach them through the VPN
and they might not answer to you. If that happens, use public DNS
resolvers like those of Google (8.8.4.4 and 8.8.8.8) or OpenDNS
(208.67.222.222 and 208.67.220.220).
For simplicity, the client and the server use the same private key and
certificate. This is certainly a terrible idea. If someone can get their
hands on the configuration on one of your clients, they will be able to
connect to your VPN, and you will have to generate new keys. Which is,
by the way, extremely easy, since each time you docker run the OpenVPN
image, a new key is created. If someone steals your configuration file
(and key), they will also be able to impersonate the VPN server (if they
can also somehow hijack your connection).
It would probably be a good idea to generate two sets of keys.
It would probably be even better to generate the server key when
running the container for the first time (as it is done now), but
generate a new client key each time the serveconfig command is
called. The command could even take the client CN as argument, and
another revoke command could be used to revoke previously issued
keys.
People have successfully used this VPN server with clients such as:
- OpenVPN on Linux,
- Viscosity on OSX (#25),
- Tunnelblick on OSX,
- OpenVPN Connect on iOS,
- (some VPN client on Android but I can't remember which).
- @besn0847/alpinevpn, a smaller image based on the Alpine distribution