[PATCH v2 net-next 6/6] vxlan: support flow dissect

[Tom Herbert]

Populate offload flow_dissect callback appropriately for VXLAN and
VXLAN-GPE.

Signed-off-by: Tom Herbert <t...@quantonium.net>
---
 drivers/net/vxlan.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index ae3a1da703c2..41e50de40af4 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -1336,6 +1336,55 @@ static bool vxlan_ecn_decapsulate(struct vxlan_sock *vs, 
void *oiph,
        return err <= 1;
 }
 
+static enum flow_dissect_ret vxlan_flow_dissect(struct sock *sk,
+                       const struct sk_buff *skb,
+                       struct flow_dissector_key_control *key_control,
+                       struct flow_dissector *flow_dissector,
+                       void *target_container, void *data,
+                       __be16 *p_proto, u8 *p_ip_proto, int *p_nhoff,
+                       int *p_hlen, unsigned int flags)
+{
+       __be16 protocol = htons(ETH_P_TEB);
+       struct vxlanhdr *vhdr, _vhdr;
+       struct vxlan_sock *vs;
+
+       vhdr = __skb_header_pointer(skb, *p_nhoff + sizeof(struct udphdr),
+                                   sizeof(_vhdr), data, *p_hlen, &_vhdr);
+       if (!vhdr)
+               return FLOW_DISSECT_RET_OUT_BAD;
+
+       vs = rcu_dereference_sk_user_data(sk);
+       if (!vs)
+               return FLOW_DISSECT_RET_OUT_BAD;
+
+       if (vs->flags & VXLAN_F_GPE) {
+               struct vxlanhdr_gpe *gpe = (struct vxlanhdr_gpe *)vhdr;
+
+               /* Need to have Next Protocol set for interfaces in GPE mode. */
+               if (gpe->version != 0 || !gpe->np_applied || gpe->oam_flag)
+                       return FLOW_DISSECT_RET_CONTINUE;
+
+               switch (gpe->next_protocol) {
+               case VXLAN_GPE_NP_IPV4:
+                       protocol = htons(ETH_P_IP);
+                       break;
+               case VXLAN_GPE_NP_IPV6:
+                       protocol = htons(ETH_P_IPV6);
+                       break;
+               case VXLAN_GPE_NP_ETHERNET:
+                       protocol = htons(ETH_P_TEB);
+                       break;
+               default:
+                       return FLOW_DISSECT_RET_CONTINUE;
+               }
+       }
+
+       *p_nhoff += sizeof(struct udphdr) + sizeof(_vhdr);
+       *p_proto = protocol;
+
+       return FLOW_DISSECT_RET_PROTO_AGAIN;
+}
+
 /* Callback from net/ipv4/udp.c to receive packets */
 static int vxlan_rcv(struct sock *sk, struct sk_buff *skb)
 {
@@ -2864,6 +2913,7 @@ static struct vxlan_sock *vxlan_socket_create(struct net 
*net, bool ipv6,
        tunnel_cfg.encap_destroy = NULL;
        tunnel_cfg.gro_receive = vxlan_gro_receive;
        tunnel_cfg.gro_complete = vxlan_gro_complete;
+       tunnel_cfg.flow_dissect = vxlan_flow_dissect;
 
        setup_udp_tunnel_sock(net, sock, &tunnel_cfg);
 
-- 
2.11.0