From d8bcc768c80e73cf4e948cb327949174b4b5b9e7 Mon Sep 17 00:00:00 2001 From: Tomasz Bursztyka Date: Thu, 12 Dec 2013 15:00:42 +0200 Subject: [PATCH] netfilter: nf_tables: Expose the table usage counter via netlink Userspace can therefore know whether a table is in use or not, and by how many chains. Suggested by Pablo Neira Ayuso. Signed-off-by: Tomasz Bursztyka Signed-off-by: Pablo Neira Ayuso --- include/uapi/linux/netfilter/nf_tables.h | 2 ++ net/netfilter/nf_tables_api.c | 3 ++- 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/include/uapi/linux/netfilter/nf_tables.h b/include/uapi/linux/netfilter/nf_tables.h index 256d36b..b25481e 100644 --- a/include/uapi/linux/netfilter/nf_tables.h +++ b/include/uapi/linux/netfilter/nf_tables.h @@ -110,11 +110,13 @@ enum nft_table_flags { * * @NFTA_TABLE_NAME: name of the table (NLA_STRING) * @NFTA_TABLE_FLAGS: bitmask of enum nft_table_flags (NLA_U32) + * @NFTA_TABLE_USE: number of chains in this table (NLA_U32) */ enum nft_table_attributes { NFTA_TABLE_UNSPEC, NFTA_TABLE_NAME, NFTA_TABLE_FLAGS, + NFTA_TABLE_USE, __NFTA_TABLE_MAX }; #define NFTA_TABLE_MAX (__NFTA_TABLE_MAX - 1) diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c index dcddc49..604512d 100644 --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -180,7 +180,8 @@ static int nf_tables_fill_table_info(struct sk_buff *skb, u32 portid, u32 seq, nfmsg->res_id = 0; if (nla_put_string(skb, NFTA_TABLE_NAME, table->name) || - nla_put_be32(skb, NFTA_TABLE_FLAGS, htonl(table->flags))) + nla_put_be32(skb, NFTA_TABLE_FLAGS, htonl(table->flags)) || + nla_put_be32(skb, NFTA_TABLE_USE, htonl(table->use))) goto nla_put_failure; return nlmsg_end(skb, nlh); -- 2.7.4