[1/2] openvswitch: support asymmetric conntrack
diff mbox series

Message ID 20191203213414.24109-1-aconole@redhat.com
State Accepted
Delegated to: David Miller
Headers show
Series
  • [1/2] openvswitch: support asymmetric conntrack
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Commit Message

Aaron Conole Dec. 3, 2019, 9:34 p.m. UTC
The openvswitch module shares a common conntrack and NAT infrastructure
exposed via netfilter.  It's possible that a packet needs both SNAT and
DNAT manipulation, due to e.g. tuple collision.  Netfilter can support
this because it runs through the NAT table twice - once on ingress and
again after egress.  The openvswitch module doesn't have such capability.

Like netfilter hook infrastructure, we should run through NAT twice to
keep the symmetry.

Fixes: 05752523e565 ("openvswitch: Interface with NAT.")
Signed-off-by: Aaron Conole <aconole@redhat.com>
---
NOTE: this is a repost to see if the email client issues go away.

 net/openvswitch/conntrack.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

Comments

David Miller Dec. 5, 2019, 12:32 a.m. UTC | #1
From: Aaron Conole <aconole@redhat.com>
Date: Tue,  3 Dec 2019 16:34:13 -0500

> The openvswitch module shares a common conntrack and NAT infrastructure
> exposed via netfilter.  It's possible that a packet needs both SNAT and
> DNAT manipulation, due to e.g. tuple collision.  Netfilter can support
> this because it runs through the NAT table twice - once on ingress and
> again after egress.  The openvswitch module doesn't have such capability.
> 
> Like netfilter hook infrastructure, we should run through NAT twice to
> keep the symmetry.
> 
> Fixes: 05752523e565 ("openvswitch: Interface with NAT.")
> Signed-off-by: Aaron Conole <aconole@redhat.com>
> ---
> NOTE: this is a repost to see if the email client issues go away.

Applied and queued up for -stable.

Patch
diff mbox series

diff --git a/net/openvswitch/conntrack.c b/net/openvswitch/conntrack.c
index df9c80bf621d..e726159cfcfa 100644
--- a/net/openvswitch/conntrack.c
+++ b/net/openvswitch/conntrack.c
@@ -903,6 +903,17 @@  static int ovs_ct_nat(struct net *net, struct sw_flow_key *key,
 	}
 	err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range, maniptype);
 
+	if (err == NF_ACCEPT &&
+	    ct->status & IPS_SRC_NAT && ct->status & IPS_DST_NAT) {
+		if (maniptype == NF_NAT_MANIP_SRC)
+			maniptype = NF_NAT_MANIP_DST;
+		else
+			maniptype = NF_NAT_MANIP_SRC;
+
+		err = ovs_ct_nat_execute(skb, ct, ctinfo, &info->range,
+					 maniptype);
+	}
+
 	/* Mark NAT done if successful and update the flow key. */
 	if (err == NF_ACCEPT)
 		ovs_nat_update_key(key, skb, maniptype);