xfrm: Add an IPsec hardware offloading API

This patch adds all the bits that are needed to do
IPsec hardware offload for IPsec states and ESP packets.
We add xfrmdev_ops to the net_device. xfrmdev_ops has
function pointers that are needed to manage the xfrm
states in the hardware and to do a per packet
offloading decision.

Joint work with:
Ilan Tayari <ilant@mellanox.com>
Guy Shapiro <guysh@mellanox.com>
Yossi Kuperman <yossiku@mellanox.com>

Signed-off-by: Guy Shapiro <guysh@mellanox.com>
Signed-off-by: Ilan Tayari <ilant@mellanox.com>
Signed-off-by: Yossi Kuperman <yossiku@mellanox.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>

1 files changed, 38 insertions, 6 deletions

diff --git a/net/xfrm/xfrm_output.c b/net/xfrm/xfrm_output.c
index 8ba29fe58352..a15088613a6c 100644
--- a/net/xfrm/xfrm_output.c
+++ b/net/xfrm/xfrm_output.c
@@ -99,12 +99,13 @@ static int xfrm_output_one(struct sk_buff *skb, int err)
 
 		skb_dst_force(skb);
 
-		/* Inner headers are invalid now. */
-		skb->encapsulation = 0;
-
-		err = x->type->output(x, skb);
-		if (err == -EINPROGRESS)
-			goto out;
+		if (xfrm_offload(skb)) {
+			x->type_offload->encap(x, skb);
+		} else {
+			err = x->type->output(x, skb);
+			if (err == -EINPROGRESS)
+				goto out;
+		}
 
 resume:
 		if (err) {
@@ -200,8 +201,38 @@ static int xfrm_output_gso(struct net *net, struct sock *sk, struct sk_buff *skb
 int xfrm_output(struct sock *sk, struct sk_buff *skb)
 {
 	struct net *net = dev_net(skb_dst(skb)->dev);
+	struct xfrm_state *x = skb_dst(skb)->xfrm;
 	int err;
 
+	secpath_reset(skb);
+
+	if (xfrm_dev_offload_ok(skb, x)) {
+		struct sec_path *sp;
+
+		sp = secpath_dup(skb->sp);
+		if (!sp) {
+			XFRM_INC_STATS(net, LINUX_MIB_XFRMOUTERROR);
+			kfree_skb(skb);
+			return -ENOMEM;
+		}
+		if (skb->sp)
+			secpath_put(skb->sp);
+		skb->sp = sp;
+
+		sp->olen++;
+		sp->xvec[skb->sp->len++] = x;
+		xfrm_state_hold(x);
+
+		if (skb_is_gso(skb)) {
+			skb_shinfo(skb)->gso_type |= SKB_GSO_ESP;
+
+			return xfrm_output2(net, sk, skb);
+		}
+
+		if (x->xso.dev && x->xso.dev->features & NETIF_F_HW_ESP_TX_CSUM)
+			goto out;
+	}
+
 	if (skb_is_gso(skb))
 		return xfrm_output_gso(net, sk, skb);
 
@@ -214,6 +245,7 @@ int xfrm_output(struct sock *sk, struct sk_buff *skb)
 		}
 	}
 
+out:
 	return xfrm_output2(net, sk, skb);
 }
 EXPORT_SYMBOL_GPL(xfrm_output);