Gentoo Archives: gentoo-security

From: Kirk Hoganson <kirk2@×××××××××.com>
To: gentoo-security@l.g.o
Subject: Re: [gentoo-security] [OT?] automatically firewalling off IPs
Date: Tue, 04 Oct 2005 17:16:04
In Reply to: Re: [gentoo-security] [OT?] automatically firewalling off IPs by boger
Yes, there are.  I use one for my work servers that is iptables based. 
I don't have any links for you unfortunately but I have seen them.  If 
you are really interested I can probably track down one I saw that used 
iptables and was a combination style.  I also know of an open source 
"magic packet" style that I could probably find a link for if you were 

boger said the following:
> Hello Kirk, > Is there IPtables based port knocker? > I dislike idea opening ports for this purpose because they can be distinguished by some way. > Promiscuous mode port knockers consume a lot of processor and > I don't think it's good for production server. > > KH> A port knocker of some sort is a much more secure solution that will > KH> allow you to block all unwanted IP's but still allow for dynamic > KH> addresses. There are port knockers that listen on various ports and > KH> work like a combination lock to open the port, and there are others that > KH> use a more secure one time pad "magic packet" kind of authentication to > KH> open the port for your IP. It is more work to setup, but it is more > KH> secure than just changing the port. Remember a few years ago when ssh > KH> had a remote exploit? You probably shouldn't leave that port open. >
-- gentoo-security@g.o mailing list


Subject Author
Re: [gentoo-security] [OT?] automatically firewalling off IPs boger <boger@×××.ru>
[gentoo-security] Port knocking Tobias Sager <moixa@×××.ch>