net/flow_dissector: Add support for QinQ dissection

Dissect the QinQ packets to get both outer and inner vlan information,
then store to the extended flow keys.

Signed-off-by: Jianbo Liu <jianbol@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h
index 8f89968..c644067 100644 (file)
--- a/include/net/flow_dissector.h
+++ b/include/net/flow_dissector.h
@@ -206,6 +206,7 @@ enum flow_dissector_key_id {
        FLOW_DISSECTOR_KEY_MPLS, /* struct flow_dissector_key_mpls */
        FLOW_DISSECTOR_KEY_TCP, /* struct flow_dissector_key_tcp */
        FLOW_DISSECTOR_KEY_IP, /* struct flow_dissector_key_ip */
+       FLOW_DISSECTOR_KEY_CVLAN, /* struct flow_dissector_key_flow_vlan */
 
        FLOW_DISSECTOR_KEY_MAX,
 };
@@ -237,6 +238,7 @@ struct flow_keys {
        struct flow_dissector_key_basic basic;
        struct flow_dissector_key_tags tags;
        struct flow_dissector_key_vlan vlan;
+       struct flow_dissector_key_vlan cvlan;
        struct flow_dissector_key_keyid keyid;
        struct flow_dissector_key_ports ports;
        struct flow_dissector_key_addrs addrs;

diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index 18cb99b..b555fc2 100644 (file)
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -589,7 +589,7 @@ bool __skb_flow_dissect(const struct sk_buff *skb,
        struct flow_dissector_key_tags *key_tags;
        struct flow_dissector_key_vlan *key_vlan;
        enum flow_dissect_ret fdret;
-       bool skip_vlan = false;
+       enum flow_dissector_key_id dissector_vlan = FLOW_DISSECTOR_KEY_MAX;
        int num_hdrs = 0;
        u8 ip_proto = 0;
        bool ret;
@@ -748,15 +748,14 @@ proto_again:
        }
        case htons(ETH_P_8021AD):
        case htons(ETH_P_8021Q): {
-               const struct vlan_hdr *vlan;
+               const struct vlan_hdr *vlan = NULL;
                struct vlan_hdr _vlan;
-               bool vlan_tag_present = skb && skb_vlan_tag_present(skb);
                __be16 saved_vlan_tpid = proto;
 
-               if (vlan_tag_present)
+               if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX &&
+                   skb && skb_vlan_tag_present(skb)) {
                        proto = skb->protocol;
-
-               if (!vlan_tag_present || eth_type_vlan(skb->protocol)) {
+               } else {
                        vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
                                                    data, hlen, &_vlan);
                        if (!vlan) {
@@ -766,20 +765,23 @@ proto_again:
 
                        proto = vlan->h_vlan_encapsulated_proto;
                        nhoff += sizeof(*vlan);
-                       if (skip_vlan) {
-                               fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
-                               break;
-                       }
                }
 
-               skip_vlan = true;
-               if (dissector_uses_key(flow_dissector,
-                                      FLOW_DISSECTOR_KEY_VLAN)) {
+               if (dissector_vlan == FLOW_DISSECTOR_KEY_MAX) {
+                       dissector_vlan = FLOW_DISSECTOR_KEY_VLAN;
+               } else if (dissector_vlan == FLOW_DISSECTOR_KEY_VLAN) {
+                       dissector_vlan = FLOW_DISSECTOR_KEY_CVLAN;
+               } else {
+                       fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
+                       break;
+               }
+
+               if (dissector_uses_key(flow_dissector, dissector_vlan)) {
                        key_vlan = skb_flow_dissector_target(flow_dissector,
-                                                            FLOW_DISSECTOR_KEY_VLAN,
+                                                            dissector_vlan,
                                                             target_container);
 
-                       if (vlan_tag_present) {
+                       if (!vlan) {
                                key_vlan->vlan_id = skb_vlan_tag_get_id(skb);
                                key_vlan->vlan_priority =
                                        (skb_vlan_tag_get_prio(skb) >> VLAN_PRIO_SHIFT);