netfilter: nft_limit: add per-byte limiting

This patch adds a new NFTA_LIMIT_TYPE netlink attribute to indicate the type of
limiting.

Contrary to per-packet limiting, the cost is calculated from the packet path
since this depends on the packet length.

The burst attribute indicates the number of bytes in which the rate can be
exceeded.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 7 insertions, 0 deletions

diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h
index cafd789..d8c8a7c 100644
--- a/include/uapi/linux/netfilter/nf_tables.h
+++ b/include/uapi/linux/netfilter/nf_tables.h
@@ -756,18 +756,25 @@ enum nft_ct_attributes {
 };
 #define NFTA_CT_MAX		(__NFTA_CT_MAX - 1)
 
+enum nft_limit_type {
+	NFT_LIMIT_PKTS,
+	NFT_LIMIT_PKT_BYTES
+};
+
 /**
  * enum nft_limit_attributes - nf_tables limit expression netlink attributes
  *
  * @NFTA_LIMIT_RATE: refill rate (NLA_U64)
  * @NFTA_LIMIT_UNIT: refill unit (NLA_U64)
  * @NFTA_LIMIT_BURST: burst (NLA_U32)
+ * @NFTA_LIMIT_TYPE: type of limit (NLA_U32: enum nft_limit_type)
  */
 enum nft_limit_attributes {
 	NFTA_LIMIT_UNSPEC,
 	NFTA_LIMIT_RATE,
 	NFTA_LIMIT_UNIT,
 	NFTA_LIMIT_BURST,
+	NFTA_LIMIT_TYPE,
 	__NFTA_LIMIT_MAX
 };
 #define NFTA_LIMIT_MAX		(__NFTA_LIMIT_MAX - 1)