---------------------------
What (Why):
- - "forwarding" header files like ipt_mac.h in
- include/linux/netfilter_ipv4/ and include/linux/netfilter_ipv6/
-
- - xt_mark match revision 0
- (superseded by xt_mark match revision 1)
-
- xt_recent: the old ipt_recent proc dir
(superseded by /proc/net/xt_recent)