netfilter: nf_tables: variable sized set element keys / data

This patch changes sets to support variable sized set element keys / data
up to 64 bytes each by using variable sized set extensions. This allows
to use concatenations with bigger data items suchs as IPv6 addresses.

As a side effect, small keys/data now don't require the full 16 bytes
of struct nft_data anymore but just the space they need.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 4 insertions, 1 deletions

diff --git a/include/net/netfilter/nf_tables.h b/include/net/netfilter/nf_tables.h
index 160577bf0f0a..cb42da1011ef 100644
--- a/include/net/netfilter/nf_tables.h
+++ b/include/net/netfilter/nf_tables.h
@@ -158,7 +158,10 @@ struct nft_userdata {
  *      @priv: element private data and extensions
  */
 struct nft_set_elem {
-        struct nft_data         key;
+        union {
+                u32             buf[NFT_DATA_VALUE_MAXLEN / sizeof(u32)];
+                struct nft_data val;
+        } key;
         void                    *priv;
 };