[NETFILTER]: nf_conntrack_sip: RTP routing optimization

Optimize call routing between NATed endpoints: when an external
registrar sends a media description that contains an existing RTP
expectation from a different SNATed connection, the gatekeeper
is trying to route the call directly between the two endpoints.

We assume both endpoints can reach each other directly and
"un-NAT" the addresses, which makes the media stream go between
the two endpoints directly.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/net/ipv4/netfilter/nf_nat_sip.c b/net/ipv4/netfilter/nf_nat_sip.c
index 4429069d9b42..bcddccddf768 100644
--- a/net/ipv4/netfilter/nf_nat_sip.c
+++ b/net/ipv4/netfilter/nf_nat_sip.c
@@ -461,6 +461,7 @@ static void __exit nf_nat_sip_fini(void)
         rcu_assign_pointer(nf_nat_sip_hook, NULL);
         rcu_assign_pointer(nf_nat_sip_expect_hook, NULL);
         rcu_assign_pointer(nf_nat_sdp_addr_hook, NULL);
+        rcu_assign_pointer(nf_nat_sdp_port_hook, NULL);
         rcu_assign_pointer(nf_nat_sdp_session_hook, NULL);
         rcu_assign_pointer(nf_nat_sdp_media_hook, NULL);
         synchronize_rcu();
@@ -471,11 +472,13 @@ static int __init nf_nat_sip_init(void)
         BUG_ON(nf_nat_sip_hook != NULL);
         BUG_ON(nf_nat_sip_expect_hook != NULL);
         BUG_ON(nf_nat_sdp_addr_hook != NULL);
+        BUG_ON(nf_nat_sdp_port_hook != NULL);
         BUG_ON(nf_nat_sdp_session_hook != NULL);
         BUG_ON(nf_nat_sdp_media_hook != NULL);
         rcu_assign_pointer(nf_nat_sip_hook, ip_nat_sip);
         rcu_assign_pointer(nf_nat_sip_expect_hook, ip_nat_sip_expect);
         rcu_assign_pointer(nf_nat_sdp_addr_hook, ip_nat_sdp_addr);
+        rcu_assign_pointer(nf_nat_sdp_port_hook, ip_nat_sdp_port);
         rcu_assign_pointer(nf_nat_sdp_session_hook, ip_nat_sdp_session);
         rcu_assign_pointer(nf_nat_sdp_media_hook, ip_nat_sdp_media);
         return 0;