negation of appid keyword

[greg.mcnathansonsnuf003 () gmx-topmail de]

Hello to all snort experts,

I'm wondering if one can create a rule using a negated appid specification.

For example: Block non http traffic over known http ports

block tcp any any -> any $HTTP_PORTS (msg:”openappid: non http activity detected over http port”; !appid: http; 
sid:1000000; rev:1;)


or block any traffic except of a specific app:

block tcp any any -> any any (msg:”openappid: non firefox traffic detected”; !appid: firefox; sid:1000000; rev:1;)


Unfortunately this will result in an error message:

FATAL ERROR: /etc/snort/rules/custom.rules(1) Unknown rule option: '!appid'.


Any help would be appreciated.

Greg


------------------------------------------------------------------------------
Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server
from Actuate! Instantly Supercharge Your Business Reports and Dashboards
with Interactivity, Sharing, Native Excel Exports, App Integration & more
Get technology previously reserved for billion-dollar corporations, FREE
http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk
_______________________________________________
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://sourceforge.net/mailarchive/forum.php?forum_name=snort-users

Please visit http://blog.snort.org to stay current on all the latest Snort news!