Snort mailing list archives
Re: How to write a rule file to detect land-attack, syn-flood
From: Erek Adams <erek () theadamsfamily net>
Date: Wed, 20 Feb 2002 12:12:42 -0800 (PST)
On Wed, 20 Feb 2002, Prerana Sharma wrote:
I am trying to learn Snort. And I am really confused with the documentation. So, could someone please tell me how to write a very simple rule file to detect a land-attack and a syn-flood.
You can't. Snort works on a 'packet grep' style of detection. "Check this packet, does it match X, Y and Z? Great, trigger Alert QQZ. If not, skip it and go on to the next one." To detect land/syn floods, you would have to write a pre-processor that would keep up with incoming syn's and flag when it hit a certain level. You might look at the code for spp_portscan.{c,h} to see something like that in action. Hope that helps! ----- Erek Adams Nifty-Type-Guy TheAdamsFamily.Net _______________________________________________ Snort-users mailing list Snort-users () lists sourceforge net Go to this URL to change user options or unsubscribe: https://lists.sourceforge.net/lists/listinfo/snort-users Snort-users list archive: http://www.geocrawler.com/redir-sf.php3?list=snort-users
Current thread:
- How to write a rule file to detect land-attack, syn-flood Prerana Sharma (Feb 20)
- Re: How to write a rule file to detect land-attack, syn-flood Erek Adams (Feb 20)