In this chapter we'll introduce fwsnort or Firewall Snort[48] (see This software is written in Perl and translates Snort rules into equivalent iptables rules. The fwsnort project utilizes the filtering and inspection capabilities of iptables—including heavy use of the iptables string match extension—in order to match Snort rules as closely as possible within an iptables ruleset.

Although it is not always possible to cleanly translate many Snort rules, due to the complexity of the Snort rules language, fwsnort is nonetheless able to translate about 60 percent of all rules contained in Snort version 2.3.3.[49]

Although fwsnort is not able to translate the complete ...

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