xfrm: Honor original L3 slave device in xfrmi policy lookup
If an xfrmi is associated to a vrf layer 3 master device,
xfrm_policy_check() fails after traffic decapsulation. The input
interface is replaced by the layer 3 master device, and hence
xfrmi_decode_session() can't match the xfrmi anymore to satisfy
policy checking.
Extend ingress xfrmi lookup to honor the original layer 3 slave
device, allowing xfrm interfaces to operate within a vrf domain.
Fixes: f203b76d7809 ("xfrm: Add virtual xfrm interfaces")
Signed-off-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
diff --git a/net/xfrm/xfrm_interface.c b/net/xfrm/xfrm_interface.c
index dbb3c194..85fec98 100644
--- a/net/xfrm/xfrm_interface.c
+++ b/net/xfrm/xfrm_interface.c
@@ -70,17 +70,28 @@
return NULL;
}
-static struct xfrm_if *xfrmi_decode_session(struct sk_buff *skb)
+static struct xfrm_if *xfrmi_decode_session(struct sk_buff *skb,
+ unsigned short family)
{
struct xfrmi_net *xfrmn;
- int ifindex;
struct xfrm_if *xi;
+ int ifindex = 0;
if (!secpath_exists(skb) || !skb->dev)
return NULL;
+ switch (family) {
+ case AF_INET6:
+ ifindex = inet6_sdif(skb);
+ break;
+ case AF_INET:
+ ifindex = inet_sdif(skb);
+ break;
+ }
+ if (!ifindex)
+ ifindex = skb->dev->ifindex;
+
xfrmn = net_generic(xs_net(xfrm_input_state(skb)), xfrmi_net_id);
- ifindex = skb->dev->ifindex;
for_each_xfrmi_rcu(xfrmn->xfrmi[0], xi) {
if (ifindex == xi->dev->ifindex &&