Well… after a couple of days digging deeper into the source code, I was able to make hummingbird 1.1.2 compile
and run in a Docker container with working network lock.
Clone my fork from https://gitlab.com/fschaeckermann/hummingbird.git and read instructions in README.md
I made it compile under Alpine Linux as well, but iptables seems to misbehave in some breaking way. Therefore the Alpine image is not really usable yet.
@whiteowl3: I shamelessly copied your
work and incorporated it in the Dockerfile - tini and entrypoint.sh and healthcheck.sh including.
The client is actually issuing modprobe and iptables commands to create the network lock (using iptables-legacy, maybe that was the reason you couldn’t see any rules?). I haven’t tested with nftables or pf. That might even work under alpine…
Also, if ipv6 gets in the picture, things go haywire! But ipv6 and Docker is an altogether different can of worms….
Have fun! And post your results here if you like.