openconnect + tinyproxy + microsocks

This Docker image contains an openconnect client (recent version with pulse/juniper support) and the tinyproxy proxy server for http/https connections (default on port 8888) and the microsocks proxy for socks5 connections (default on port 8889) in a small alpine linux image (around 80 MB).

OpenConnect version v9.12
Using OpenSSL 3.1.8 11 Feb 2025. Features present: TPM (OpenSSL ENGINE not present), RSA software token, HOTP software token, TOTP software token, Yubikey OATH, DTLS, ESP
Supported protocols: anyconnect (default), nc, gp, pulse, f5, fortinet, array

You can find the image on docker hub: https://hub.docker.com/r/wazum/openconnect-proxy

Requirements

If you don't want to set the environment variables on the command line set the environment variables in a .env file:

OPENCONNECT_URL=<gateway URL>
OPENCONNECT_USER=<username>
OPENCONNECT_PASSWORD=<password>
OPENCONNECT_OPTIONS=--authgroup <VPN group> \
	--servercert <VPN server certificate> --protocol=<Protocol> \
	--reconnect-timeout 86400
VPN_SPLIT=0

(available protocols, see above)

Don't use quotes around the values!

See the openconnect documentation for available options.

Either set the password in the .env file or leave the variable OPENCONNECT_PASSWORD unset, so you get prompted when starting up the container.

Optionally set a multi factor authentication code:

OPENCONNECT_MFA_CODE=<Multi factor authentication code>

Run container in foreground

To start the container in foreground run:

docker run -it --rm --privileged --env-file=.env \
  -p 8888:8888 -p 8889:8889 wazum/openconnect-proxy:latest

The proxies are listening on ports 8888 (http/https) and 8889 (socks). Either use --net host or -p <local port>:8888 -p <local port>:8889 to make the proxy ports available on the host.

Without using a .env file set the environment variables on the command line with the docker run option -e:

docker run … -e OPENCONNECT_URL=vpn.gateway.com/example \
-e OPENCONNECT_OPTIONS='<Openconnect Options>' \
-e OPENCONNECT_USER=<Username> …

Run container in background

To start the container in daemon mode (background) set the -d option:

docker run -d -it --rm …

In daemon mode you can view the stderr log with docker logs:

docker logs `docker ps|grep "wazum/openconnect-proxy"|awk -F' ' '{print $1}'`

Use container with docker-compose

vpn:
  container_name: openconnect_vpn
  image: wazum/openconnect-proxy:latest
  privileged: true
  env_file:
    - .env
  ports:
    - 8888:8888
    - 8889:8889
  cap_add:
    - NET_ADMIN
  networks:
    - mynetwork

Set the environment variables for openconnect in the .env file again (or specify another file) and map the configured ports in the container to your local ports if you want to access the VPN on the host too when running your containers. Otherwise only the docker containers in the same network have access to the proxy ports.

Route traffic through VPN container

Let's say you have a vpn container defined as above, then add network_mode option to your other containers:

depends_on:
  - vpn
network_mode: "service:vpn"

Keep in mind that networks, extra_hosts, etc. and network_mode are mutually exclusive!

vpn-slice

If you want to route only specific traffic through the VPN container you can use vpn-slice.

Set this in your .env file:

VPN_SPLIT=1
VPN_ROUTES=172.16.0.0/12 XXX.XXX.XXX.XXX/32

Configure proxy

The container is connected via openconnect and now you can configure your browser and other software to use one of the proxies (8888 for http/https or 8889 for socks).

For example FoxyProxy (available for Firefox, Chrome) is a suitable browser extension.

You may also set environment variables:

export http_proxy="http://127.0.0.1:8888/"
export https_proxy="http://127.0.0.1:8888/"

composer, git (if you don't use the git+ssh protocol, see below) and others use these.

ssh through the proxy

You need nc (netcat), corkscrew or something similar to make this work.

Unfortunately some git clients (e.g. Gitkraken) don't use the settings from ssh config and you can't pull/push from a repository that's reachable (DNS resolution) only through VPN.

nc (netcat, ncat)

Set a ProxyCommand in your ~/.ssh/config file like

Host <hostname>
     ProxyCommand   nc -x 127.0.0.1:8889 %h %p

or (depending on your ncat version)

Host <hostname>
     ProxyCommand   ncat --proxy 127.0.0.1:8889 --proxy-type socks5 %h %p

and your connection will be passed through the proxy. The above example is for using git with ssh keys.

corkscrew

An alternative is corkscrew (e.g. install with brew install corkscrew on mac OS)

Host <hostname>
     ProxyCommand   corkscrew 127.0.0.1 8888 %h %p

Multiple jump hosts

You can add multiple jump hosts in your ~/.ssh/config file with corkscrew etc. like:

Host admin-proxy
    ProxyCommand corkscrew 127.0.0.1 8888 %h %p

Host actual-host
    User someuser
    ProxyJump admin-proxy

$ ssh user@actual-host

Local Machine               HTTP PROXY           JUMP HOST           TARGET
+----------------+          (TinyProxy)          (admin-proxy)       (actual-host)
|                |          
|  SSH Client    |         127.0.0.1:8888    
|  ~/.ssh/config |               +                    +                   +
|  + corkscrew   |               |                    |                   |
|                +-------------->|                    |                   |
|                |               |                    |                   |
+----------------+               |                    |                   |
                                 +------------------->|                   |
                                                      |                   |
                                                      +------------------>|

- SSH + Corkscrew -----> TinyProxy (8888)
- TinyProxy -----------> admin-proxy
- admin-proxy ---------> actual-host (as someuser)

Build

You can build the container yourself with:

docker build -f build/Dockerfile -t wazum/openconnect-proxy:custom ./build

Support

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