netfilter: flow table support for IPv4
This patch adds the IPv4 flow table type, that implements the datapath
flow table to forward IPv4 traffic. Rationale is:
1) Look up for the packet in the flow table, from the ingress hook.
2) If there's a hit, decrement ttl and pass it on to the neighbour layer
for transmission.
3) If there's a miss, packet is passed up to the classic forwarding
path.
This patch also supports layer 3 source and destination NAT.
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
3 files changed