Educause Security Discussion mailing list archives
Re: Barracuda Spam Filter
From: Matthew Keller <kellermg () POTSDAM EDU>
Date: Wed, 27 Jul 2005 15:15:25 -0400
SA uses the Apache v2 license, which does not have copyleft. Also, the GPL doesn't require someone using GPL'd software to open all their code, just the changes/additions to the GPL'd software itself. On Wed, 2005-07-27 at 13:35 -0500, Information Security wrote:
Dave Koontz wrote:It was actually pretty easy to spot what it was via a sample message headers someone posted here. Oddly enough, while flipping through the 'Network Computing' magazine I received today (July 21st issue) Page WC 6 says... "Barracuda Networks keeps costs low by using off-the-shelf hardware and open source applications on a hardened Linux kernel. "I can't remember which licence SA uses but if it's GPL then the Barracuda software is presumably available. Although they probably have independent modules for the quarantine vs the spam detection to limit how much source they're obliged to give out. Another interesting product is PMAS (for VMS and some others) which is clearly a Spam Assassin clone, but apparently was rewritten from scratch to avoid release under the GPL. However PMAS's input files appear to be identical to SA's in format and to a large extent in content. That's one way of avoiding the GPL that I'm not morally comfortable with even though I think it probably obeys the letter of it. (Although PMAS is a good product, if you're in the VMS world. Good quarantine interface - in fact I'm not aware of any general-purpose freeware quarantine interface worth using - do tell me if you find one.) My take on SA is that it's default rules and threshholds are way too loose to be used as-is. In our system at UTPA, I use SA with a very high threshhold to catch spams that I am very sure are spams (and it only catches about 10% of the spam this way), but I feed those spams plus others from spamtrap email addresses into a Bayesian filter (spamprobe - I think it is better than SA's built-in Bayesian system) as training data. The latter brings the recognition up into the 99.X% level, although with greylisting and a small hand-crafted and double-checked blacklist of corporate spam IP sources, it's now 99% of hardly anything :-) The one last hack we need to make it all work is a way of feeding back corrections: I wrote a dummy IMAP module which you can drop emails on and they can be picked up in a directory and fed to the Bayesian system. It's a write-only IMAP server and ignores any username or password you give it, so client configuration is minimal. I would *love* to be able to hand out our system as a pre-packaged kit as easy to install as an appliance. The one piece of technology which has been too tricky for me until now is that in order to be configuration-free, it has to be implemented as a transparent filter at the IP level. I've recently come across OpenBSD's pf code and I think that I now know how to do that under pf, so that project may still come off if I can negotiate enough time at work to do it. (Writing spam software is not what I'm actually paid to do, if you hadn't guessed, but I'ld written most of it before I came here and the University never says no to something free, especially when it actually works as well ;-) I would *love* to work in the antispam area rather than just have it as an occassional hobby...) Graham
-- Matthew Keller signat-url: http://mattwork.potsdam.edu/signat-url/ "Would you have banned the Internet to save the libraries?" -I, Robot
Current thread:
- Re: Barracuda Spam Filter, (continued)
- Re: Barracuda Spam Filter Parker, Ron (Jul 26)
- Re: Barracuda Spam Filter Dave Koontz (Jul 26)
- Re: Barracuda Spam Filter Matthew Keller (Jul 27)
- Re: Barracuda Spam Filter Michael_Maloney (Jul 27)
- Re: Barracuda Spam Filter Tony Harris (Jul 27)
- Re: Barracuda Spam Filter Matthew Keller (Jul 27)
- Re: Barracuda Spam Filter Dave Koontz (Jul 27)
- Re: Barracuda Spam Filter Hall, Rand (Jul 27)
- Re: Barracuda Spam Filter Information Security (Jul 27)
- Re: Barracuda Spam Filter Parker, Ron (Jul 27)
- Re: Barracuda Spam Filter Matthew Keller (Jul 27)
- Re: Barracuda Spam Filter Matthew Keller (Jul 27)
- Re: Barracuda Spam Filter Jamie A. Stapleton (Jul 27)
- Re: Barracuda Spam Filter Matthew Keller (Jul 28)
- Re: Barracuda Spam Filter Jamie A. Stapleton (Jul 28)
- Re: Barracuda Spam Filter Fox, Danny D. (Jul 28)
- Re: Barracuda Spam Filter Matthew Keller (Jul 28)
- Re: Barracuda Spam Filter Hall, Rand (Jul 28)
- Re: Barracuda Spam Filter Tom Bossie (Jul 28)
- Re: Barracuda Spam Filter Tristan RHODES (Aug 01)