Projects / fwsnort


fwsnort translates snort rules into an equivalent iptables ruleset. By making use of the iptables string match module, fwsnort can detect application layer signatures which exist in many snort rules. fwsnort adds a --hex-string option to iptables, which allows snort rules that contain hex characters to be input directly into iptables rulesets without modification. In addition, fwsnort makes use of the IPTables::Parse Perl module in order to (optionally) restrict the snort rule translation to only those rules that specify traffic that could potentially be allowed through an existing iptables policy.

Operating Systems

Recent releases

  •  05 Feb 2014 04:25

    Release Notes: A bugfix for vulnerability CVE-2014-0039, in which an attacker-controlled fwsnort.conf file could be read by fwsnort when not running as root. This was caused by fwsnort reading './fwsnort.conf' when not running as root, and when a path to the config file was not explicitly set with -c on the command line. This behavior has been changed to require the user to specify a path to fwsnort.conf with -c when not running as root.

    •  22 Dec 2012 02:55

      Release Notes: This release adds a new comprehensive test suite, a faster iptables/ip6tables capabilities testing routine, and fixes for hex string encoding for some Snort content matches with syntax-busting characters.

      •  29 Apr 2012 01:33

        Release Notes: This release switches the default policy load stance to load all translated Snort rules into the running iptables policy by default. This was made possible after fwsnort made use of the iptables-save format for policy instantiation. Updated to use the NetAddr::IP module from CPAN. A bugfix for translated ICMP rules and ICMP type requirements in recent versions of iptables.

        •  02 Sep 2011 12:43

          Release Notes: A bugfix for the 'Couldn't load target' error seen on some Linux systems. A bugfix for interpreting pattern ordering in Snort rules with relative pattern matches. Updated to the latest Emerging Threats rule set.

          •  29 Jul 2011 02:26

            Release Notes: Snort fast_pattern support and iptables multiport match support were added. The --QUEUE and --NFQUEUE modes were enhanced. Support was added for the conntrack module for connection tracking. Case-insensitive pattern matching was added via the --icase argument to the iptables string match extension. A couple of minor bugs were fixed.


            Project Spotlight


            A Fluent OpenStack client API for Java.


            Project Spotlight

            TurnKey TWiki Appliance

            A TWiki appliance that is easy to use and lightweight.