Just wondered if any one is using block lists for their docker containers.

IPSum publishes a great list of IPs worth blocking.

The thing is, I know docker networking interacts with iptables in a complex way such that the iptables INPUT chain is ignored.

The docker docs say you can put custom rules in DOCKER-USER chain, but my iptables knowledge isn’t great and I think I’m more likely to mess something up than to have any success.

The thing is, I’m sure that this is something loads of other people have encountered, and I’m sure there must be an easier way.

  • Matt The Horwood
    25 days ago

    I would have a cron that runs a script to pull the list and update IPset, this might not work.

    make a file on your docker server with the below in it, set the file to execute chmod +x file.sh

    ipset -q flush ipsum
    ipset -q create ipsum hash:ip
    for ip in $(curl --compressed https://raw.githubusercontent.com/stamparm/ipsum/master/ipsum.txt 2>/dev/null | grep -v "#" | grep -v -E "\s[1-2]$" | cut -f 1); do ipset add ipsum $ip; done
    iptables -D INPUT -m set --match-set ipsum src -j DROP 2>/dev/null
    iptables -I INPUT -m set --match-set ipsum src -j DROP

    Then add a cron file in /etc/cron.d that runs the script every 24 hours

    10 3 * * * root /root/file.sh