Snort mailing list archives

Re: Cannot get alert from dynamic_example preprocessor in output


From: Victor Roemer <vroemer () sourcefire com>
Date: Tue, 19 Feb 2013 16:16:17 -0500

I don't see where you actually enabled a preprocessor rule in your
configuration..

Should look something like this...

alert (msg:"Just lookn at dem source ports!"; sid:1; gid:256; rev:1;
metadata:rule-type preproc;)


Altering msg to your liking..

On Tue, Feb 19, 2013 at 3:09 PM, Андрей Меньков <
nothingelsematters7 () gmail com> wrote:

I have installed latest snort version from site sources. I have Linux Mint
14 Nadia as my OS.
I need to write a dynamic processor, so I use dynamic_example preprocessor
that is in tarball with Snort.
It's the code https://gist.github.com/AndreiMenkou/4989418

I have a problem with outputting alerts and I don't know how to solve it.
My dynamic preprocessor is loaded when snort is run. And ExampleProcess
function that is used to process Snort packets is called.
The problem actually is in alertAdd function call:

_dpd.alertAdd(GENERATOR_EXAMPLE, SRC_PORT_MATCH, 1, 0, 3, SRC_PORT_MATCH_STR, 0);

I'm sure that it's called but no alerts are generated
I have added output to file (using FILE* of <stdio.h>) before call to alertAdd function - and it works.
So the problem is actually with alertAdd itself

I thought that this problem will be solved after configuring output modules, but this didn't helped.
I have added my custom rule in local.rules and alerts are generated and wroten to expected file. But for 
_dpd.alertAdd there is nothing :-(


How can I solve this problem? Any help would be appreciated

My conf file for output modules look like :

# unified2
# Recommended for most installs
output unified2: filename merged.log, limit 128, nostamp, mpls_event_types, vlan_event_types

# Additional configuration for specific types of installs
output alert_unified2: filename snort.alert, limit 128, nostamp
output log_unified2: filename snort.log, limit 128, nostamp

# syslog
output alert_syslog: LOG_AUTH LOG_ALERT

#alert fast
output alert_fast: alert.fast

# pcap
# output log_tcpdump: tcpdump.log

# metadata reference data.  do not modify these lines
include classification.config
include reference.config


Full snort.conf file : https://gist.github.com/AndreiMenkou/4989412


Config for dynamic_example preprocessor:


preprocessor dynamic_example: port 80


Snort is running using command :
sudo snort -i wlan0 -c Projects/snort/etc/snort.conf -l ./log/



------------------------------------------------------------------------------
Everyone hates slow websites. So do we.
Make your web apps faster with AppDynamics
Download AppDynamics Lite for free today:
http://p.sf.net/sfu/appdyn_d2d_feb
_______________________________________________
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!

------------------------------------------------------------------------------
Everyone hates slow websites. So do we.
Make your web apps faster with AppDynamics
Download AppDynamics Lite for free today:
http://p.sf.net/sfu/appdyn_d2d_feb
_______________________________________________
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!

Current thread: