Snort mailing list archives
RE: catch all rule
From: "Graham M Locke" <graham () waldonet net mt>
Date: Tue, 19 Jun 2001 12:46:55 +0200
On Date: Tue, 18 Jun 2002 09:17:56 +0200 (CEST), barre wrote:
In the following example , I want to protect my dmz and will make a "alert" rule for all traffic from and to my dmz. alert any any any -> any any (msg: \"tcp dmz traffic";) But in this case, alerts will be generated when people access my webserver. So I make this nice pass rule to grant access to my webserver.
pass tcp !MY_NET any -> webserver 80 Because this pass rule is applied below the alert rule, I have to use the
-o option, to make sure that this previous rule makes an exception to the
other rules. But in this scenario, I don't check the content of the pass rule for malicious traffic using the other alert rules. But if I delete the pass rule, it triggers the "catch all other traffic" rule. Therefor: is there an other way to implement a "catch all traffic" rule? Using this rule, you can write rules for all allowed traffic , and alert for all non-defined traffic. All other signatures (http malicious traffic for example) will still be applied to all traffic, even if they are in the pass or catch all rules. Someone has an idea? Thanks a lot. barre
Try: alert tcp !MY_NET any -> any !80 (msg: \"tcp dmz traffic";) and: alert udp !MY_NET any -> any !80 (msg: \"udp dmz traffic";) Which says 'alert on protocol NOT from my network -> any network NOT port 80' and you wont need the -o switch. You were 95% there with your pass rule. Regards Graham. _______________________________________________ Snort-users mailing list Snort-users () lists sourceforge net Go to this URL to change user options or unsubscribe: http://lists.sourceforge.net/lists/listinfo/snort-users Snort-users list archive: http://www.geocrawler.com/redir-sf.php3?list=snort-users
Current thread:
- catch all rule barre (Jun 18)
- Re: catch all rule Vitaly Osipov (Jun 19)
- <Possible follow-ups>
- RE: catch all rule Frank Knobbe (Jun 18)
- RE: catch all rule Graham M Locke (Jun 19)