closes-bug:#1420452 While mirroring the tunneled packet, tunnel headers

are removed and ethernet header is added from Encap nh to ensure that
Mirroring application sees a regular ethernet packet. After IRB, the
packet can be L2 packet and might contain ethernet header in the Tunnel
payload. In this case, the ethernet header need not be added from Encap
NH. This functionality is added by verifying the type of NH.

Change-Id: I0797c9db5e25ac09d51ddd3cdb9b25c632b812b9

dp-core/vr_mirror.c

@@ -373,7 +373,7 @@ vr_mirror(struct vrouter *router, uint8_t mirror_id,
     struct vr_pcap *pcap;
     struct vr_mirror_entry *mirror;
     struct vr_mirror_meta_entry *mme;
-    unsigned int captured_len;
+    unsigned int captured_len, clone_len = VR_MIRROR_PKT_HEAD_SPACE;
     unsigned int mirror_md_len = 0;
     unsigned char default_mme[2] = {0xff, 0x0};
     void *mirror_md;
@@ -397,6 +397,7 @@ vr_mirror(struct vrouter *router, uint8_t mirror_id,
         mirror_md = default_mme;
     }
 
+    clone_len += mirror_md_len;
     nh = mirror->mir_nh;
     pkt = vr_pclone(pkt);
     if (!pkt)
@@ -409,23 +410,28 @@ vr_mirror(struct vrouter *router, uint8_t mirror_id,
     reset = true;
     if (pkt->vp_if && pkt->vp_if->vif_type == VIF_TYPE_PHYSICAL) {
         pkt_nh = pkt->vp_nh;
-        if (pkt_nh && pkt_nh->nh_type == NH_ENCAP && pkt_nh->nh_dev &&
-            pkt_nh->nh_dev->vif_set_rewrite && pkt_nh->nh_encap_len) {
+        if (pkt_nh && (pkt_nh->nh_flags & NH_FLAG_VALID) &&
+                    (pkt_nh->nh_type == NH_ENCAP)) {
 
             reset = false;
-            if (vr_pcow(pkt, VR_MIRROR_PKT_HEAD_SPACE + mirror_md_len +
-                    pkt_nh->nh_encap_len))
+            if (pkt_nh->nh_family == AF_INET)
+                clone_len += pkt_nh->nh_encap_len;
+
+            if (vr_pcow(pkt, clone_len))
                 goto fail;
 
-            if (!pkt_nh->nh_dev->vif_set_rewrite(pkt_nh->nh_dev, pkt, fmd,
+
+            if (pkt_nh->nh_family == AF_INET) {
+                if (!pkt_nh->nh_dev->vif_set_rewrite(pkt_nh->nh_dev, pkt, fmd,
                     pkt_nh->nh_data, pkt_nh->nh_encap_len))
                 goto fail;
+            }
         }
     }
 
     if (reset) {
         vr_preset(pkt);
-        if (vr_pcow(pkt, VR_MIRROR_PKT_HEAD_SPACE + mirror_md_len))
+        if (vr_pcow(pkt, clone_len))
             goto fail;
     }