Filtergen compiles high-level language into rules that can filter packets for diverse packet filters, creating an efficient network security process.
The tool currently works with just Linux iptables and ipchains. However, the Cisco IOS backend has been started, although it's incomplete. The package aims to provide support for Darren Reed's ipfilter at some point in the future. It's worth noting that filtergen doesn't generate optimal rulesets and has some limitations that need resolving. Nonetheless, it remains an exceptionally useful and practical tool.
Many large software projects aren't written entirely in assembly language these days. While assembly language can be more efficient, it also takes longer to implement and bugfix and isn't portable to other systems. Furthermore, it's more challenging for others to understand, update and audit. Similarly, filtergen aims to solve the problem of packet filters being written in the equivalent of assembler or inflexible macro languages.
The latest release of filtergen has a few noteworthy features. For instance, it comes with a fixed non-working example filter syntax man page, a fix for a 64-bit warning in filter.c netmask calculation, and a better feedback system to provide error feedback. Furthermore, it has an add "-F [policy]" flush option that makes it easier to work with.
In conclusion, filtergen is an indispensable tool that streamlines the process of generating packet filtering rules for a range of packet filters. While it's not perfect, it remains one of the best options available, and the new release comes with a few notable improvements.
Version 0.11: N/A