Reimplementing pf as an eBPF/XDP dataplane on Linux (blog.nfsensei.org)

PF configuration language that author considers to be “the clearest expression of firewall intent anyone has shipped” is 95% the configuration language of ipfilter, the initial solaris and bsd firewall software. Quite suspicious that the author doesn’t mention it, especially when pf started merely as a clone of the latter.

this seems very interesting, but the prose is extremely hard to read