From 5d50aa83e2c8e91ced2cca77c198b468ca9210f4 Mon Sep 17 00:00:00 2001 From: Aaron Conole Date: Tue, 3 Dec 2019 16:34:13 -0500 Subject: [PATCH] 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 Signed-off-by: David S. Miller --- net/openvswitch/conntrack.c | 11 +++++++++++ 1 file changed, 11 insertions(+) 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);