- Add support for dynamic NETMAP algorithm (stateful net-to-net).
- Add most of the support for the dynamic NAT rules; a little bit more
userland work is needed to finish this up and enable.
- Replace 'stateful-ends' with more permissive 'stateful-all'.
- Add various tunable parameters and document them, see npf-params(7).
- Reduce the memory usage of the connection state table (conndb).
- Portmap rewrite: use memory more efficiently, handle addresses dynamically.
- Bug fix: add splsoftnet()/splx() around the thmap writers and comment.
- npftest: clean up and simplify; fix some memleaks to make ASAN happy.
The documented default "flags S/SAFR" for stateful rules that affect
TCP packets but don't specify any flags, doesn't actually get applied
to a rule like "pass stateful out all". The big problem with this is
that when you then do a "block return-rst" for an incoming packet, the
generated RST packet will create state for the connection attempt it's
blocking, so that a second attempt from the same source will pass.
This change makes the default flags actually apply to such simple
rules. It also fixes a related bug in the code generation for the
flag matching, where part of the action could erroneously be omitted.
Reviewed by <rmind>
Closes PR bin/54124
Pullup to NetBSD 8
- Convert NPF connection table to thmap. State lookup is now lock-free.
- Improve connection state G/C: it is now incremental and tunable.
- Add support for dynamic NAT address. Translation addresses can now be
selected from a pool of addresses. There are two selection algorithms,
"ip-hash" and "round-robin" (see the man page).
- Translation address can be specified as e.g. ifaddrs(wm0) in npf.conf
to dynamically choose an IP from the interface address(es).
- Add support for the NETMAP algorithm with static NAT for net-to-net
translation (it is equivalent to iptables NETMAP logic).
- Convert 'ipset' tables to use thmap; the table lookup is now lock-free.
- Misc improvements, bug fixes and more unit tests.
- Bump NPF_VERSION (will also bump libnpf).
- This conversion significantly simplifies the code and moves NPF to
a binary serialisation format (replacing the XML-like format).
- Fix some memory/reference leaks and possibly use-after-free bugs.
- Bump NPF_VERSION as this change makes libnpf incompatible with the
previous versions. Also, different serialisation format means NPF
connection/config saving and loading is not compatible with the
previous versions either.
Thanks to christos@ for extra testing.
The TCP flags option is not only for the stateful tracking. Dynamic NAT
implies NAPT; algorithms, at least for now, are for static NAT mappings.
Mention that ALG ICMP is also for traceroute behind NAT; also mention
"MSS clamping" (some users might search for this term, so keeping the
terminology is helpful).
