I just made Suricata 1.4rc1 available with some pretty exciting features: unix socket mode and IP reputation.

Unix socket

First of all, Eric Leblond’s work on the Unix socket was merged. The unix socket work consists of two parts. The unix socket protocol implementation and a new runmode.

The protocol implementation is based on JSON messages over unix socket. Eric will be fully documenting it soon. Currently the commands are limited to shutting down and getting some basic stats. This part isn’t very exciting yet, but the groundwork for many future extensions has been laid.

The part that is exciting right now, is the unix socket runmode. That this does is start Suricata with all the rules and such, and then it waits for commands on the unix socket. Then the commands will be a pcap filename – log directory pair. This pcap will then be inspected against the rules and the logs go into the log directory supplied. As this can be easily scripted (a python script is provided), it’s a very fast way to test your pcap collections, as the overhead of starting and stopping is skipped.

This may initialy appeal mostly for those of you doing sandnetting and malware analysis, where tens of thousands of pcaps and automatically processed every hour or day, I think this could grow into a feature for a wider audience as well. For example, I could see use in Sguil or Snorby, or pretty much every event manager with full packet capture support, adding an option to scan a pcap associated with an event again. Maybe against _all_ rules, instead of the tuned set running on the live sensors. Maybe you can re-inspect old sessions against the current rules this way to find hits on attacks that were 0-days at the time, etc.

I think there could be many possibilities.

IP Reputation

A slightly more polished version of the code I discussed here is now available in this release. It’s one of those things where it will be very interesting to see how people will put it to use.

Matt Jonkman just wrote some of his ideas to the Emerging Threats mailing list: one of the ideas Matt wrote about is to amend weak rules with reputation data. So if you have a signature that is phrone to false positives, you probably disable it currently. But what if you combine it with reputation data? If the weak rule fires on a sketchy ip, it may be a more reliable alert.

We’ll see how this plays out.

1.4 final

We’re hoping that if nothing big happens, we can do a mid-December 1.4 final release. So please consider running this new release. It’s running very stable on quite a number of places, ISP networks, Lab networks, home networks, sandnetting networks, etc. But we need much more testing to find issues and/or gain confidence that we have found the most important issues. Thanks for helping out!