netfilter: nf_conntrack: prepare namespace support for l4 protocol trackers

This patch prepares the namespace support for layer 4 protocol trackers.
Basically, this modifies the following interfaces:

* nf_ct_[un]register_sysctl
* nf_conntrack_l4proto_[un]register

to include the namespace parameter. We still use init_net in this patch
to prepare the ground for follow-up patches for each layer 4 protocol
tracker.

We add a new net_id field to struct nf_conntrack_l4proto that is used
to store the pernet_operations id for each layer 4 protocol tracker.

Note that AF_INET6's protocols do not need to do sysctl compat. Thus,
we only register compat sysctl when l4proto.l3proto != AF_INET6.

Acked-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Gao feng <gaofeng@cn.fujitsu.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 12 insertions, 0 deletions

diff --git a/include/net/netns/conntrack.h b/include/net/netns/conntrack.h
index a053a19870cf..1f53038b0d1b 100644
--- a/include/net/netns/conntrack.h
+++ b/include/net/netns/conntrack.h
@@ -8,6 +8,18 @@
 struct ctl_table_header;
 struct nf_conntrack_ecache;
 
+struct nf_proto_net {
+#ifdef CONFIG_SYSCTL
+	struct ctl_table_header *ctl_table_header;
+	struct ctl_table        *ctl_table;
+#ifdef CONFIG_NF_CONNTRACK_PROC_COMPAT
+	struct ctl_table_header *ctl_compat_header;
+	struct ctl_table        *ctl_compat_table;
+#endif
+#endif
+	unsigned int		users;
+};
+
 struct netns_ct {
 	atomic_t		count;
 	unsigned int		expect_count;