tunnel: support copying TTL and flow label from inner to outer

Type: feature

The added functionality is to support copying TTL and flow label from
inner to outer. The .api was extened to support expressing this and also
adding a common tunnel endpoint type. i find it best to make API changes
in one patch so there are less versions of the API.

Signed-off-by: Neale Ranns <neale@graphiant.com>
Change-Id: I755c1e3f4c475058792af39c1abeda92129efb76
diff --git a/src/vnet/tunnel/tunnel_dp.h b/src/vnet/tunnel/tunnel_dp.h
index deef408..3db22a8 100644
--- a/src/vnet/tunnel/tunnel_dp.h
+++ b/src/vnet/tunnel/tunnel_dp.h
@@ -19,18 +19,21 @@
 #define __TUNNEL_DP_H__
 
 #include <vnet/tunnel/tunnel.h>
+#include <vnet/mpls/mpls_lookup.h>
 
 static_always_inline void
 tunnel_encap_fixup_4o4 (tunnel_encap_decap_flags_t flags,
 			const ip4_header_t * inner, ip4_header_t * outer)
 {
-  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP))
     ip4_header_set_dscp (outer, ip4_header_get_dscp (inner));
-  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN)
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN))
     ip4_header_set_ecn (outer, ip4_header_get_ecn (inner));
-  if ((flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DF) &&
-      ip4_header_get_df (inner))
+  if (PREDICT_FALSE ((flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DF) &&
+		     ip4_header_get_df (inner)))
     ip4_header_set_df (outer);
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_HOP_LIMIT))
+    ip4_header_set_ttl (outer, ip4_header_get_ttl (inner));
 }
 
 static_always_inline void
@@ -38,8 +41,8 @@
 				 const ip4_header_t * inner,
 				 ip4_header_t * outer)
 {
-  if (flags & (TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP |
-	       TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN))
+  if (PREDICT_FALSE (flags & (TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP |
+			      TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN)))
     {
       ip_csum_t sum = outer->checksum;
       u8 tos = outer->tos;
@@ -53,8 +56,8 @@
 	ip_csum_update (outer->checksum, tos, outer->tos, ip4_header_t, tos);
       outer->checksum = ip_csum_fold (sum);
     }
-  if ((flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DF) &&
-      ip4_header_get_df (inner))
+  if (PREDICT_FALSE ((flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DF) &&
+		     ip4_header_get_df (inner)))
     {
       ip_csum_t sum = outer->checksum;
       u16 tos = outer->flags_and_fragment_offset;
@@ -92,10 +95,12 @@
 tunnel_encap_fixup_6o4 (tunnel_encap_decap_flags_t flags,
 			const ip6_header_t * inner, ip4_header_t * outer)
 {
-  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP))
     ip4_header_set_dscp (outer, ip6_dscp_network_order (inner));
-  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN)
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN))
     ip4_header_set_ecn (outer, ip6_ecn_network_order ((inner)));
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_HOP_LIMIT))
+    ip4_header_set_ttl (outer, ip6_hop_limit_network_order (inner));
 }
 
 static_always_inline void
@@ -103,8 +108,8 @@
 				 const ip6_header_t * inner,
 				 ip4_header_t * outer)
 {
-  if (flags & (TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP |
-	       TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN))
+  if (PREDICT_FALSE (flags & (TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP |
+			      TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN)))
     {
       ip_csum_t sum = outer->checksum;
       u8 tos = outer->tos;
@@ -124,30 +129,50 @@
 tunnel_encap_fixup_6o6 (tunnel_encap_decap_flags_t flags,
 			const ip6_header_t * inner, ip6_header_t * outer)
 {
-  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP))
     ip6_set_dscp_network_order (outer, ip6_dscp_network_order (inner));
-  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN)
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN))
     ip6_set_ecn_network_order (outer, ip6_ecn_network_order (inner));
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_FLOW_LABEL))
+    ip6_set_flow_label_network_order (outer,
+				      ip6_flow_label_network_order (inner));
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_HOP_LIMIT))
+    ip6_set_hop_limit_network_order (outer,
+				     ip6_hop_limit_network_order (inner));
 }
 
 static_always_inline void
 tunnel_encap_fixup_4o6 (tunnel_encap_decap_flags_t flags,
-			const ip4_header_t * inner, ip6_header_t * outer)
+			const vlib_buffer_t *b, const ip4_header_t *inner,
+			ip6_header_t *outer)
 {
-  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP))
     ip6_set_dscp_network_order (outer, ip4_header_get_dscp (inner));
-  if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN)
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_ECN))
     ip6_set_ecn_network_order (outer, ip4_header_get_ecn (inner));
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_HOP_LIMIT))
+    ip6_set_hop_limit_network_order (outer, ip4_header_get_ttl (inner));
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_FLOW_LABEL))
+    ip6_set_flow_label_network_order (
+      outer, (0 != vnet_buffer (b)->ip.flow_hash ?
+		vnet_buffer (b)->ip.flow_hash :
+		ip4_compute_flow_hash (inner, IP_FLOW_HASH_DEFAULT)));
 }
 
 static_always_inline void
 tunnel_encap_fixup_mplso6 (tunnel_encap_decap_flags_t flags,
+			   const vlib_buffer_t *b,
 			   const mpls_unicast_header_t *inner,
 			   ip6_header_t *outer)
 {
   if (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_DSCP)
     ip6_set_dscp_network_order (outer,
 				vnet_mpls_uc_get_exp (inner->label_exp_s_ttl));
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_ENCAP_COPY_FLOW_LABEL))
+    ip6_set_flow_label_network_order (
+      outer, (0 != vnet_buffer (b)->ip.flow_hash ?
+		vnet_buffer (b)->ip.flow_hash :
+		mpls_compute_flow_hash (inner, IP_FLOW_HASH_DEFAULT)));
 }
 
 static_always_inline void
@@ -163,7 +188,7 @@
 tunnel_decap_fixup_4o6 (tunnel_encap_decap_flags_t flags,
 			ip4_header_t * inner, const ip6_header_t * outer)
 {
-  if (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN)
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN))
     ip4_header_set_ecn_w_chksum (inner, ip6_ecn_network_order (outer));
 }
 
@@ -171,7 +196,7 @@
 tunnel_decap_fixup_6o6 (tunnel_encap_decap_flags_t flags,
 			ip6_header_t * inner, const ip6_header_t * outer)
 {
-  if (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN)
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN))
     ip6_set_ecn_network_order (inner, ip6_ecn_network_order (outer));
 }
 
@@ -179,7 +204,7 @@
 tunnel_decap_fixup_6o4 (tunnel_encap_decap_flags_t flags,
 			ip6_header_t * inner, const ip4_header_t * outer)
 {
-  if (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN)
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN))
     ip6_set_ecn_network_order (inner, ip4_header_get_ecn (outer));
 }
 
@@ -187,7 +212,7 @@
 tunnel_decap_fixup_4o4 (tunnel_encap_decap_flags_t flags,
 			ip4_header_t * inner, const ip4_header_t * outer)
 {
-  if (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN)
+  if (PREDICT_FALSE (flags & TUNNEL_ENCAP_DECAP_FLAG_DECAP_COPY_ECN))
     ip4_header_set_ecn_w_chksum (inner, ip4_header_get_ecn (outer));
 }