net: Add a xfrm validate function to validate_xmit_skb
When we do IPsec offloading, we need a fallback for
packets that were targeted to be IPsec offloaded but
rerouted to a device that does not support IPsec offload.
For that we add a function that checks the offloading
features of the sending device and and flags the
requirement of a fallback before it calls the IPsec
output function. The IPsec output function adds the IPsec
trailer and does encryption if needed.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
diff --git a/net/core/dev.c b/net/core/dev.c
index ef9fe60e..5f0a864 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2972,6 +2972,9 @@ static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device
__skb_linearize(skb))
goto out_kfree_skb;
+ if (validate_xmit_xfrm(skb, features))
+ goto out_kfree_skb;
+
/* If packet is not checksummed and device does not
* support checksumming for this protocol, complete
* checksumming here.
diff --git a/net/xfrm/xfrm_device.c b/net/xfrm/xfrm_device.c
index 9bac2ba..8ec8a3f 100644
--- a/net/xfrm/xfrm_device.c
+++ b/net/xfrm/xfrm_device.c
@@ -22,6 +22,35 @@
#include <net/xfrm.h>
#include <linux/notifier.h>
+int validate_xmit_xfrm(struct sk_buff *skb, netdev_features_t features)
+{
+ int err;
+ struct xfrm_state *x;
+ struct xfrm_offload *xo = xfrm_offload(skb);
+
+ if (skb_is_gso(skb))
+ return 0;
+
+ if (xo) {
+ x = skb->sp->xvec[skb->sp->len - 1];
+ if (xo->flags & XFRM_GRO || x->xso.flags & XFRM_OFFLOAD_INBOUND)
+ return 0;
+
+ x->outer_mode->xmit(x, skb);
+
+ err = x->type_offload->xmit(x, skb, features);
+ if (err) {
+ XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR);
+ return err;
+ }
+
+ skb_push(skb, skb->data - skb_mac_header(skb));
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(validate_xmit_xfrm);
+
int xfrm_dev_state_add(struct net *net, struct xfrm_state *x,
struct xfrm_user_offload *xuo)
{
