NPF(7)

NAME
NPF - NetBSD packet filter

DESCRIPTION
NPF is a layer 3 packet filter, supporting IPv4 and IPv6 as well as layer 4 protocols such as TCP, UDP, and ICMP. It was designed with a focus on high performance, scalability, and modularity.

NPF was written from scratch in 2009 and is distributed under the 2-clause BSD license.

FEATURES
NPF offers the traditional set of features provided by packet filters. Some key features are:

•   Stateful inspection (connection tracking).

•   Network address translation (NAT). This includes static (stateless) and dynamic (stateful) translation, port translation, bi-directional NAT, etc.

•   IPv6-to-IPv6 network prefix translation (NPTv6).

•   Tables for efficient IP sets.

•   Application Level Gateways (e.g., to support traceroute).

•   NPF uses BPF with just-in-time (JIT) compilation.

•   Rule procedures and a framework for NPF extensions.

•   Traffic normalization (extension).

•   Packet logging (extension).

For a full set of features and their description, see the NPF documentation and other manual pages.

SEE ALSO
libnpf(3), bpf(4), bpfjit(4), npf.conf(5), pcap-filter(7), npfctl(8)

NPF documentation: http://www.netbsd.org/~rmind/npf/

HISTORY
NPF first appeared in NetBSD 6.0.

AUTHORS
NPF was designed and implemented by Mindaugas Rasiukevicius.