This patch adds the following utilities:
They all use Patrick's nf_tables infrastructure plus my compatibility
xtables, xtables-restore and xtables-save are syntax compatible with
iptables, iptables-restore and iptables-save.
Semantics aims to be similar, still the main exception is that there
is no commit operation. Thus, we incrementally add/delete rules without
entire table locking.
The following options are also not yet implemented:
-Z (this requires adding expr->ops->reset(...) so nft_counters can reset
internal state of expressions while dumping it)
-R and -E (this requires adding this feature to nf_tables)
-f (can be implemented with expressions: payload 6 (2-bytes) + bitwise a&b^!b + cmp neq 0)
But those are a matter of time to get them done.
A new utility, xtables-config, is available to register tables and
chains. By default there is a configuration file that adds backward
compatible tables and chains under iptables/etc/xtables.conf. You have
to call this utility first to register tables and chains.
However, it would be possible to automagically register tables and
chains while using xtables and xtables-restore to get similar operation
than with iptables.
Signed-off-by: Pablo Neira Ayuso <firstname.lastname@example.org>