From f76e672dd1e7ba62a777bfccfc9ea4d9e17c7aee Mon Sep 17 00:00:00 2001
From: "Gauvain \"GovanifY\" Roussel-Tarbouriech" <govanify@anarchist.pw>
Date: Wed, 6 Jun 2018 23:38:39 +0200
Subject: I have no idea what I'm doing; beginning GRO impl

---
 src/socket.c | 75 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 74 insertions(+), 1 deletion(-)

diff --git a/src/socket.c b/src/socket.c
index 6c81cc6..1221ec5 100644
--- a/src/socket.c
+++ b/src/socket.c
@@ -300,6 +300,78 @@ err:
 	kfree_skb(skb);
 	return 0;
 }
+static struct sk_buff **gro_receive(struct sock *sk,
+					  struct sk_buff **head,
+					  struct sk_buff *skb)
+{
+	struct wireguard_device *wg;
+	struct sk_buff *p, **pp = NULL;
+	struct vxlanhdr *vh, *vh2;
+	unsigned int hlen, off_vx;
+	int flush = 1;
+	struct vxlan_sock *vs = rcu_dereference_sk_user_data(sk);
+	__be32 flags;
+	struct gro_remcsum grc;
+
+
+	wg = sk->sk_user_data;
+    // TODO: Check this key?
+    //pubkey_hashtable_init(&wg->peer_hashtable);
+	skb_gro_remcsum_init(&grc);
+
+	off_vx = skb_gro_offset(skb);
+	hlen = off_vx + sizeof(*vh);
+	vh   = skb_gro_header_fast(skb, off_vx);
+	if (skb_gro_header_hard(skb, hlen)) {
+		vh = skb_gro_header_slow(skb, hlen, off_vx);
+		if (unlikely(!vh))
+			goto out;
+	}
+
+	skb_gro_postpull_rcsum(skb, vh, sizeof(struct vxlanhdr));
+
+	flags = vh->vx_flags;
+
+	if ((flags & VXLAN_HF_RCO) && (vs->flags & VXLAN_F_REMCSUM_RX)) {
+		vh = vxlan_gro_remcsum(skb, off_vx, vh, sizeof(struct vxlanhdr),
+				       vh->vx_vni, &grc,
+				       !!(vs->flags &
+					  VXLAN_F_REMCSUM_NOPARTIAL));
+
+		if (!vh)
+			goto out;
+	}
+
+	skb_gro_pull(skb, sizeof(struct vxlanhdr)); /* pull vxlan header */
+
+	for (p = *head; p; p = p->next) {
+		if (!NAPI_GRO_CB(p)->same_flow)
+			continue;
+
+		vh2 = (struct vxlanhdr *)(p->data + off_vx);
+		if (vh->vx_flags != vh2->vx_flags ||
+		    vh->vx_vni != vh2->vx_vni) {
+			NAPI_GRO_CB(p)->same_flow = 0;
+			continue;
+		}
+	}
+
+	pp = call_gro_receive(eth_gro_receive, head, skb);
+	flush = 0;
+
+out:
+	skb_gro_remcsum_cleanup(skb, &grc);
+	skb->remcsum_offload = 0;
+	NAPI_GRO_CB(skb)->flush |= flush;
+
+	return pp;
+}
+
+static int gro_complete(struct sock *sk, struct sk_buff *skb, int nhoff)
+{
+	return eth_gro_complete(skb, nhoff + sizeof(struct vxlanhdr));
+}
+
 
 static inline void sock_free(struct sock *sock)
 {
@@ -322,7 +394,8 @@ int socket_init(struct wireguard_device *wg, u16 port)
 	struct udp_tunnel_sock_cfg cfg = {
 		.sk_user_data = wg,
 		.encap_type = 1,
-		.encap_rcv = receive
+        .gro_receive = gro_receive,
+	    .gro_complete = gro_complete
 	};
 	struct socket *new4 = NULL, *new6 = NULL;
 	struct udp_port_cfg port4 = {
-- 
cgit v1.2.3-59-g8ed1b