Date: Sun, 09 Apr 2023 00:33:01 UTC
On 2023-04-08 0:47, Andrea Venturoli wrote: > On 4/8/23 04:56, Mel Pilgrim wrote: >>> Can anyone suggest something equivalent in the port tree? >> >> Have a look at fail2ban. It's design intent is monitoring running >> services, but really it's just a set of log file regex filters. Anything >> that logs network activity can feed it. > > Hello and thanks for answering. > In fact I'm already using fail2ban for "running" services. > > Portsenty is a bit different, in that it's conceived to listen on ports > used by non-running services. > I.e. > Got a SMTP server? Let fail2ban check its logs. > No? Let portsentry listen on port 25. > > I thought about writing regexes for fail2ban to check if ipfw denied > access to ports where portsentry used to listen. > So far it's the best idea I've come up with, but I hoped for something > simpler (i.e. more close to how portsentry worked). That's exactly what I suggest. IME dropping/ignoring packets to closed ports slows scanners down enough as it is, and the result is the same: they just see a non-responsive host. But completeness, peace of mind, etc. FWIW, you can still build and use portsentry either extratree or copy the port to your local category.