Add vxlan-bypass feature to IP6 forwarding path

Add vxlan-bypass feature which can be enabled on the IP6 underlay
interface which receive VXLAN packets to accelerate VXLAN decap
processing. The CLI to enable/disable it is:
    set interface ip6 vxlan-bypass <interface> [del]
The vxlan-bypass feature is already supported on the IP4 underlay
interface. The CLI to enable/disable it is:
    set interface ip vxlan-bypass <interface> [del]

Move vxlan-bypass API/CLI support code from decap.c to vxlan.c.
Also fixed two issues in the VXLAN decap path in the vxlan-input node:
1. Add verification of VXLAN packet FIB index with the encap-vrf-id
   of the VXLAN tunnel.
2. Fix checking of VXLANoIPv6 packet mcast DIP against that of the
   IP6 mcast VXLAN tunnel.

Change-Id: I2bad4074a468c48fbb8bb5ac64f6437190756ed2
Signed-off-by: John Lo <loj@cisco.com>

2 files changed, 12 insertions, 1 deletions

diff --git a/src/vnet/ip/ip6.h b/src/vnet/ip/ip6.h
index 6fecd42dc61..152698733e8 100644
--- a/src/vnet/ip/ip6.h
+++ b/src/vnet/ip/ip6.h
@@ -426,6 +426,10 @@ int vnet_ip6_nd_term (vlib_main_t * vm,
 		      ip6_header_t * ip,
 		      u32 sw_if_index, u16 bd_index, u8 shg);
 
+u8 *format_ip6_forward_next_trace (u8 * s, va_list * args);
+
+u32 ip6_tcp_udp_icmp_validate_checksum (vlib_main_t * vm, vlib_buffer_t * p0);
+
 int vnet_set_ip6_classify_intfc (vlib_main_t * vm, u32 sw_if_index,
 				 u32 table_index);
 extern vlib_node_registration_t ip6_lookup_node;
diff --git a/src/vnet/ip/ip6_forward.c b/src/vnet/ip/ip6_forward.c
index ac47b3ad1fb..50951c27495 100644
--- a/src/vnet/ip/ip6_forward.c
+++ b/src/vnet/ip/ip6_forward.c
@@ -588,6 +588,13 @@ VNET_FEATURE_INIT (ip6_vpath, static) =
 {
   .arc_name = "ip6-unicast",
   .node_name = "vpath-input-ip6",
+  .runs_before = VNET_FEATURES ("ip6-vxlan-bypass"),
+};
+
+VNET_FEATURE_INIT (ip6_vxlan_bypass, static) =
+{
+  .arc_name = "ip6-unicast",
+  .node_name = "ip6-vxlan-bypass",
   .runs_before = VNET_FEATURES ("ip6-lookup"),
 };
 
@@ -921,7 +928,7 @@ typedef struct
 }
 ip6_forward_next_trace_t;
 
-static u8 *
+u8 *
 format_ip6_forward_next_trace (u8 * s, va_list * args)
 {
   CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);