Snort mailing list archives
Re: content question
From: Martin Roesch <roesch () sourcefire com>
Date: Sun, 29 Sep 2002 20:38:47 -0400
In 1.8.x you can do this: Alert tcp $HOME_NET $SOMEPORT -> any any (content: "DCC SEND"; nocase; content: ".mp3"; nocase; msg: "MP3 DCC Found";) In 1.9 you can do this: Alert tcp $HOME_NET $SOMEPORT -> any any (flow: established, from_client; content: "DCC SEND"; nocase; content: ".mp3"; distance: 1; nocase; msg: "MP3 DCC Found";) The "distance" keyword gives you a relative offset from the end of the last match, so it basically acts as a wildcarding mechanism. You can also use the new "within" keyword to limit how deep into the packet from the end of the distance it'll search before it stops. -Marty On 9/29/02 4:43 AM, "Petre Bandac" <petre () kgb ro> wrote:
I want to block all dcc sends which contain mp3, avi, mpeg and other large files, allowing the rest am I allowd to use a wildcard in the content rule ? I presume not (haven't tried yet, though). can I concatenate two/more content rules ? my content text looks like this: DCC SEND any_file_name.mp3, and I am interested only in DCC SEND and the extension thanks, petre
-- Martin Roesch - Founder/CTO Sourcefire Inc. - (410) 290-1616 Sourcefire: Professional Snort Sensor and Management Console appliances roesch () sourcefire com - http://www.sourcefire.com Snort: Open Source Network IDS - http://www.snort.org ------------------------------------------------------- This sf.net email is sponsored by:ThinkGeek Welcome to geek heaven. http://thinkgeek.com/sf _______________________________________________ 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:
- content question Petre Bandac (Sep 29)
- Re: content question Martin Roesch (Sep 29)