flow_dissector: add mpls support (v2)

Add support for parsing MPLS flows to the flow dissector in preparation for
adding MPLS match support to cls_flower.

Signed-off-by: Benjamin LaHaise <benjamin.lahaise@netronome.com>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Simon Horman <simon.horman@netronome.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Eric Dumazet <jhs@mojatatu.com>
Cc: Hadar Hen Zion <hadarh@mellanox.com>
Cc: Gao Feng <fgao@ikuai8.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 22 insertions, 3 deletions

diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index c9cf425303f8..28d94bce4df8 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -126,9 +126,11 @@ __skb_flow_dissect_mpls(const struct sk_buff *skb,
 {
         struct flow_dissector_key_keyid *key_keyid;
         struct mpls_label *hdr, _hdr[2];
+        u32 entry, label;
 
         if (!dissector_uses_key(flow_dissector,
-                                FLOW_DISSECTOR_KEY_MPLS_ENTROPY))
+                                FLOW_DISSECTOR_KEY_MPLS_ENTROPY) &&
+            !dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS))
                 return FLOW_DISSECT_RET_OUT_GOOD;
 
         hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
@@ -136,8 +138,25 @@ __skb_flow_dissect_mpls(const struct sk_buff *skb,
         if (!hdr)
                 return FLOW_DISSECT_RET_OUT_BAD;
 
-        if ((ntohl(hdr[0].entry) & MPLS_LS_LABEL_MASK) >>
-            MPLS_LS_LABEL_SHIFT == MPLS_LABEL_ENTROPY) {
+        entry = ntohl(hdr[0].entry);
+        label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;
+
+        if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS)) {
+                struct flow_dissector_key_mpls *key_mpls;
+
+                key_mpls = skb_flow_dissector_target(flow_dissector,
+                                                     FLOW_DISSECTOR_KEY_MPLS,
+                                                     target_container);
+                key_mpls->mpls_label = label;
+                key_mpls->mpls_ttl = (entry & MPLS_LS_TTL_MASK)
+                                        >> MPLS_LS_TTL_SHIFT;
+                key_mpls->mpls_tc = (entry & MPLS_LS_TC_MASK)
+                                        >> MPLS_LS_TC_SHIFT;
+                key_mpls->mpls_bos = (entry & MPLS_LS_S_MASK)
+                                        >> MPLS_LS_S_SHIFT;
+        }
+
+        if (label == MPLS_LABEL_ENTROPY) {
                 key_keyid = skb_flow_dissector_target(flow_dissector,
                                                       FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
                                                       target_container);