nftables: add flags offload to flowtable

allow flags (currently only offload) in flowtables like it is stated
here: https://lwn.net/Articles/804384/

tested on mt7622/Bananapi-R64

table ip filter {
	flowtable f {
		hook ingress priority filter + 1
		devices = { lan3, lan0, wan }
		flags offload;
	}

	chain forward {
		type filter hook forward priority filter; policy accept;
		ip protocol { tcp, udp } flow add @f
	}
}

table ip nat {
	chain post {
		type nat hook postrouting priority filter; policy accept;
		oifname "wan" masquerade
	}
}

Signed-off-by: Frank Wunderlich <frank-w@public-files.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 8 insertions, 0 deletions

diff --git a/include/rule.h b/include/rule.h
index 523435f6..4ef24eb4 100644
--- a/include/rule.h
+++ b/include/rule.h
@@ -188,6 +188,14 @@ enum chain_flags {
 };
 
 /**
+ * enum flowtable_flags - flowtable flags
+ *
+ */
+enum flowtable_flags {
+	FLOWTABLE_F_HW_OFFLOAD	= 0x1, /* NF_FLOWTABLE_HW_OFFLOAD in linux nf_flow_table.h */
+};
+
+/**
  * struct prio_spec - extendend priority specification for mixed
  *                    textual/numerical parsing.
  *