netfilter: add and use nf_ct_netns_get/put

currently aliased to try_module_get/_put.
Will be changed in next patch when we add functions to make use of ->net
argument to store usercount per l3proto tracker.

This is needed to avoid registering the conntrack hooks in all netns and
later only enable connection tracking in those that need conntrack.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/include/net/netfilter/nf_conntrack.h b/include/net/netfilter/nf_conntrack.h
index d9d52c020a70..5916aa9ab3f0 100644
--- a/include/net/netfilter/nf_conntrack.h
+++ b/include/net/netfilter/nf_conntrack.h
@@ -181,6 +181,10 @@ static inline void nf_ct_put(struct nf_conn *ct)
 int nf_ct_l3proto_try_module_get(unsigned short l3proto);
 void nf_ct_l3proto_module_put(unsigned short l3proto);
 
+/* load module; enable/disable conntrack in this namespace */
+int nf_ct_netns_get(struct net *net, u8 nfproto);
+void nf_ct_netns_put(struct net *net, u8 nfproto);
+
 /*
  * Allocate a hashtable of hlist_head (if nulls == 0),
  * or hlist_nulls_head (if nulls == 1)