diff mbox series

[ovs-dev,19/23] datapath: support asymmetric conntrack

Message ID 1597963790-12362-20-git-send-email-gvrose8192@gmail.com
State Superseded
Headers show
Series Add support for Linux kernels up to 5.9.x | expand

Commit Message

Gregory Rose Aug. 20, 2020, 10:49 p.m. UTC 
From: aaron conole <aconole@redhat.com>

Upstream commit:
    commit 5d50aa83e2c8e91ced2cca77c198b468ca9210f4
    author: aaron conole <aconole@redhat.com>
    date:   tue dec 3 16:34:13 2019 -0500

    openvswitch: support asymmetric conntrack

    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>
    signed-off-by: david s. miller <davem@davemloft.net>

Fixes: c5f6c06b58d6 ("datapath: Interface with NAT.")
Cc: aaron conole <aconole@redhat.com>
Signed-off-by: Greg Rose <gvrose8192@gmail.com>
---
 datapath/conntrack.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

Comments

Aaron Conole Aug. 25, 2020, 2:32 p.m. UTC | #1 
Greg Rose <gvrose8192@gmail.com> writes:

> From: aaron conole <aconole@redhat.com>
>
> Upstream commit:
>     commit 5d50aa83e2c8e91ced2cca77c198b468ca9210f4
>     author: aaron conole <aconole@redhat.com>
>     date:   tue dec 3 16:34:13 2019 -0500
>
>     openvswitch: support asymmetric conntrack
>
>     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>
>     signed-off-by: david s. miller <davem@davemloft.net>
>
> Fixes: c5f6c06b58d6 ("datapath: Interface with NAT.")
> Cc: aaron conole <aconole@redhat.com>
> Signed-off-by: Greg Rose <gvrose8192@gmail.com>
> ---

Acked-by: Aaron Conole <aconole@redhat.com>
diff mbox series

Patch

diff --git a/datapath/conntrack.c b/datapath/conntrack.c
index 5b4d6cc..c7a318b 100644
--- a/datapath/conntrack.c
+++ b/datapath/conntrack.c
@@ -978,6 +978,17 @@  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);