SMTP_NETWORKS doesn't work unless container is run in host mode?

[adamshand]

Hey thanks for this image, I've been using it a lot recently! Much appreciated. :-)

Perhaps I'm missing something, but I believe that SMTP_NETWORKS doesn't work as currently described.

Unless the container is running in host mode, Postfix sees all requests as coming from the Docker host.

For example, when I connect and send email from a public IP, Postfix sees the connection as coming from 10.0.0.2, eg.

Dec 05 23:51:26 postfix postfix/smtpd[103]: connect from unknown[10.0.0.2]
Dec 05 23:51:36 postfix postfix/smtpd[103]: ECE5A38BD43: client=unknown[10.0.0.2]
Dec 05 23:51:44 postfix postfix/cleanup[107]: ECE5A38BD43: warning: header Subject: blasdhkf adslkfjads lfka sjdfklasf from unknown[10.0.0.2]; from=<[email protected]> to=<[email protected]> proto=ESMTP helo=<foo>

This means that anyone who exposes port 25 to the world is creating an open relay.