UDP Encapsulation.

A UDP-encap object that particiapates in the FIB graph and contributes
DPO to teh output chain. It thereofre resembles a tunnel but without the
interface. FIB paths (and henace routes) can then be created to egress
through the UDP-encap. Said routes can have MPLS labels, hence this also
allows MPLSoUPD.
Encap is uni-directional. For decap, one still registers with the UDP port
dispatcher.

Change-Id: I23bd345523b20789a1de1b02022ea1148ca50797
Signed-off-by: Neale Ranns <nranns@cisco.com>

3 files changed, 30 insertions, 4 deletions

diff --git a/src/vnet/ip/ip.api b/src/vnet/ip/ip.api
index df3ae9646c4..85e4b8e04c3 100644
--- a/src/vnet/ip/ip.api
+++ b/src/vnet/ip/ip.api
@@ -368,13 +368,18 @@ autoreply define sw_interface_ip6_set_link_local_address
     @param is_unreach - Drop the packet and rate limit send ICMP unreachable
     @param is_prohibit - Drop the packet and rate limit send ICMP prohibited
     @param is_ipv6 - 0 if an ip4 route, else ip6
-    @param is_local - 
+    @param is_local - The route will result in packets sent to VPP IP stack
+    @param is_udp_encap - The path describes a UDP-o-IP encapsulation.
     @param is_classify - 
     @param is_multipath - Set to 1 if this is a multipath route, else 0
     @param is_source_lookup - The the path is a deaggregate path (i.e. a lookup
     	   		      in another table) is the lookup on the packet's
 			      source address or destination.
-    @param next_hop_weight - 
+    @param next_hop_weight - Weight for Unequal cost multi-path
+    @param next_hop_preference - Path that are up that have the best preference are
+                                 are used for forwarding. lower value is better.
+    @param next_hop_id - Used when the path resolves via an object that has a unique
+                         identifier.
     @param dst_address_length - 
     @param dst_address[16] - 
     @param next_hop_address[16] - 
@@ -390,6 +395,7 @@ autoreply define ip_add_del_route
   u32 table_id;
   u32 classify_table_index;
   u32 next_hop_table_id;
+  u32 next_hop_id;
   u8 create_vrf_if_needed;
   u8 is_add;
   u8 is_drop;
@@ -403,8 +409,10 @@ autoreply define ip_add_del_route
   u8 is_resolve_attached;
   u8 is_l2_bridged;
   u8 is_source_lookup;
+  u8 is_udp_encap;
   u8 next_hop_weight;
   u8 next_hop_preference;
+  u8 next_hop_proto;
   u8 dst_address_length;
   u8 dst_address[16];
   u8 next_hop_address[16];
diff --git a/src/vnet/ip/ip_api.c b/src/vnet/ip/ip_api.c
index fad518f18a5..20e19205756 100644
--- a/src/vnet/ip/ip_api.c
+++ b/src/vnet/ip/ip_api.c
@@ -832,10 +832,12 @@ add_del_route_t_handler (u8 is_multipath,
 			 u8 is_rpf_id,
 			 u8 is_l2_bridged,
 			 u8 is_source_lookup,
+			 u8 is_udp_encap,
 			 u32 fib_index,
 			 const fib_prefix_t * prefix,
 			 dpo_proto_t next_hop_proto,
 			 const ip46_address_t * next_hop,
+			 u32 next_hop_id,
 			 u32 next_hop_sw_if_index,
 			 u8 next_hop_fib_index,
 			 u16 next_hop_weight,
@@ -883,6 +885,11 @@ add_del_route_t_handler (u8 is_multipath,
     path_flags |= FIB_ROUTE_PATH_SOURCE_LOOKUP;
   if (is_multicast)
     entry_flags |= FIB_ENTRY_FLAG_MULTICAST;
+  if (is_udp_encap)
+    {
+      path_flags |= FIB_ROUTE_PATH_UDP_ENCAP;
+      path.frp_udp_encap_id = next_hop_id;
+    }
 
   path.frp_flags = path_flags;
 
@@ -1112,8 +1119,10 @@ ip4_add_del_route_t_handler (vl_api_ip_add_del_route_t * mp)
 				   mp->is_resolve_attached, 0, 0,
 				   mp->is_l2_bridged,
 				   mp->is_source_lookup,
+				   mp->is_udp_encap,
 				   fib_index, &pfx, DPO_PROTO_IP4,
 				   &nh,
+				   ntohl (mp->next_hop_id),
 				   ntohl (mp->next_hop_sw_if_index),
 				   next_hop_fib_index,
 				   mp->next_hop_weight,
@@ -1173,8 +1182,10 @@ ip6_add_del_route_t_handler (vl_api_ip_add_del_route_t * mp)
 				   mp->is_resolve_attached, 0, 0,
 				   mp->is_l2_bridged,
 				   mp->is_source_lookup,
+				   mp->is_udp_encap,
 				   fib_index, &pfx, DPO_PROTO_IP6,
-				   &nh, ntohl (mp->next_hop_sw_if_index),
+				   &nh, ntohl (mp->next_hop_id),
+				   ntohl (mp->next_hop_sw_if_index),
 				   next_hop_fib_index,
 				   mp->next_hop_weight,
 				   mp->next_hop_preference,
diff --git a/src/vnet/ip/lookup.c b/src/vnet/ip/lookup.c
index 3d5dc36c9a0..a376e51d789 100644
--- a/src/vnet/ip/lookup.c
+++ b/src/vnet/ip/lookup.c
@@ -368,11 +368,11 @@ vnet_ip_route_cmd (vlib_main_t * vm,
   unformat_input_t _line_input, *line_input = &_line_input;
   fib_route_path_t *rpaths = NULL, rpath;
   dpo_id_t dpo = DPO_INVALID, *dpos = NULL;
+  u32 table_id, is_del, udp_encap_id;
   fib_prefix_t *prefixs = NULL, pfx;
   mpls_label_t out_label, via_label;
   clib_error_t *error = NULL;
   u32 weight, preference;
-  u32 table_id, is_del;
   vnet_main_t *vnm;
   u32 fib_index;
   f64 count;
@@ -527,6 +527,13 @@ vnet_ip_route_cmd (vlib_main_t * vm,
 	  rpath.frp_proto = DPO_PROTO_IP6;
 	  vec_add1 (rpaths, rpath);
 	}
+      else if (unformat (line_input, "via udp-encap %d", &udp_encap_id))
+	{
+	  rpath.frp_udp_encap_id = udp_encap_id;
+	  rpath.frp_flags |= FIB_ROUTE_PATH_UDP_ENCAP;
+	  rpath.frp_proto = fib_proto_to_dpo (pfx.fp_proto);
+	  vec_add1 (rpaths, rpath);
+	}
       else if (unformat (line_input,
 			 "lookup in table %d", &rpath.frp_fib_index))
 	{