[HICN-602] Added bidirectional udp tunnels

- Implemented a udp decapsulation node
- Added a hash table to identify the incoming udp tunnel when
  an interest or data packets are received
- Added udp punting through udp_register_dst_port

Signed-off-by: Alberto Compagno <acompagn+fdio@cisco.com>
Change-Id: Iffea4d81c5ea8ce8ccbbfd749113f06a698a2afe

4 files changed, 983 insertions, 0 deletions

diff --git a/hicn-plugin/src/udp_tunnels/udp_decap.h b/hicn-plugin/src/udp_tunnels/udp_decap.h
new file mode 100644
index 000000000..adbec3f03
--- /dev/null
+++ b/hicn-plugin/src/udp_tunnels/udp_decap.h
@@ -0,0 +1,16 @@
+/*
+ * Copyright (c) 2020 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+extern vlib_node_registration_t udp_decap_node;
diff --git a/hicn-plugin/src/udp_tunnels/udp_decap_node.c b/hicn-plugin/src/udp_tunnels/udp_decap_node.c
new file mode 100644
index 000000000..6a5831c2b
--- /dev/null
+++ b/hicn-plugin/src/udp_tunnels/udp_decap_node.c
@@ -0,0 +1,629 @@
+/*
+ * Copyright (c) 2020 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <vnet/fib/fib_table.h>
+
+#include "udp_tunnel.h"
+#include "../mgmt.h"
+#include "../hicn.h"
+#include "../strategy_dpo_ctx.h"
+
+/**
+ * @File
+ *
+ * Definition of the nodes for ip incomplete faces.
+ */
+
+vlib_node_registration_t udp_decap_node;
+
+static char *udp_decap_error_strings[] = {
+#define _(sym, string) string,
+  foreach_hicnfwd_error
+#undef _
+};
+
+/* Trace context struct */
+typedef enum
+{
+  UDP4_DECAP_NEXT_LOOKUP_IP4,
+  UDP4_DECAP_NEXT_LOOKUP_IP6,
+  UDP4_DECAP_N_NEXT,
+} udp4_decap_next_t;
+
+typedef enum
+{
+ UDP6_DECAP_NEXT_LOOKUP_IP4,
+ UDP6_DECAP_NEXT_LOOKUP_IP6,
+ UDP6_DECAP_N_NEXT,
+} udp6_decap_next_t;
+
+typedef struct udp4_decap_trace_t_
+{
+  ip4_header_t ip;
+  udp_header_t udp;
+} udp4_decap_trace_t;
+
+typedef struct udp6_decap_trace_t_
+{
+  ip6_header_t ip;
+  udp_header_t udp;
+} udp6_decap_trace_t;
+
+typedef struct udp_decap_trace_t_
+{
+  union
+  {
+    udp4_decap_trace_t udp4;
+    udp6_decap_trace_t udp6;
+  };
+
+  u8 isv6;
+  u8 ishicn;
+} udp_decap_trace_t;
+
+
+static u8 *
+format_udp_decap_trace (u8 * s, va_list * args)
+{
+  CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+  CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+  udp_decap_trace_t *t;
+
+  t = va_arg (*args, udp_decap_trace_t *);
+
+  if (t->isv6)
+    {
+      s = format (s, "%U\n  %U \n %s",
+                  format_ip4_header, &t->udp6.ip, sizeof (t->udp6.ip),
+                  format_udp_header, &t->udp6.udp, sizeof (t->udp6.udp),
+                  t->ishicn ? "hICN udp tunnel" : "");
+    }
+  else
+    {
+      s = format (s, "%U\n  %U \n %s",
+                  format_ip4_header, &t->udp4.ip, sizeof (t->udp4.ip),
+                  format_udp_header, &t->udp4.udp, sizeof (t->udp4.udp),
+                  t->ishicn ? "hICN udp tunnel" : "");
+    }
+  return (s);
+}
+
+static_always_inline void
+udp_decap_trace_buffer (vlib_main_t * vm, vlib_node_runtime_t * node,
+                        u8 isv6, vlib_buffer_t * b)
+{
+  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) &&
+		     (b->flags & VLIB_BUFFER_IS_TRACED)))
+    {
+      udp_decap_trace_t *t =
+	vlib_add_trace (vm, node, b, sizeof (*t));
+      t->isv6 = isv6;
+      hicn_buffer_t *hb = hicn_get_buffer(b);
+
+      if (isv6)
+        {
+          clib_memcpy(&(t->udp6.udp), vlib_buffer_get_current(b) + sizeof(ip6_header_t), sizeof(udp_header_t));
+          clib_memcpy(&(t->udp6.ip), vlib_buffer_get_current(b), sizeof(ip6_header_t));
+          t->ishicn = hb->flags & hb->flags & HICN_BUFFER_FLAGS_FROM_UDP6_TUNNEL;
+        }
+      else
+        {
+          clib_memcpy(&(t->udp4.udp), vlib_buffer_get_current(b) + sizeof(ip4_header_t), sizeof(udp_header_t));
+          clib_memcpy(&(t->udp4.ip), vlib_buffer_get_current(b), sizeof(ip4_header_t));
+          t->ishicn = hb->flags & HICN_BUFFER_FLAGS_FROM_UDP4_TUNNEL;
+        }
+    }
+}
+
+static uword
+udp4_decap_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                   vlib_frame_t * frame)
+{
+  u32 n_left_from, *from, *to_next, next_index;
+
+  from = vlib_frame_vector_args (frame);
+  n_left_from = frame->n_vectors;
+  next_index = node->cached_next_index;
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+
+      /* Dual loop, X2 */
+      while (n_left_from >= 8 && n_left_to_next >= 4)
+	{
+          vlib_buffer_t *b0, *b1, *b2, *b3;
+	  u32 bi0, bi1, bi2, bi3;
+	  u32 next0, next1, next2, next3;
+
+          {
+	    vlib_buffer_t *b4, *b5, *b6, *b7;
+	    b4 = vlib_get_buffer (vm, from[4]);
+	    b5 = vlib_get_buffer (vm, from[5]);
+	    b6 = vlib_get_buffer (vm, from[6]);
+	    b7 = vlib_get_buffer (vm, from[7]);
+	    CLIB_PREFETCH (b4, CLIB_CACHE_LINE_BYTES, STORE);
+	    CLIB_PREFETCH (b5, CLIB_CACHE_LINE_BYTES, STORE);
+	    CLIB_PREFETCH (b6, CLIB_CACHE_LINE_BYTES, STORE);
+	    CLIB_PREFETCH (b7, CLIB_CACHE_LINE_BYTES, STORE);
+	  }
+
+	  bi0 = from[0];
+	  bi1 = from[1];
+	  bi2 = from[2];
+	  bi3 = from[3];
+
+	  from += 4;
+	  n_left_from -= 4;
+	  to_next[0] = bi0;
+	  to_next[1] = bi1;
+	  to_next[2] = bi2;
+	  to_next[3] = bi3;
+
+	  to_next += 4;
+	  n_left_to_next -= 4;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+	  b1 = vlib_get_buffer (vm, bi1);
+	  b2 = vlib_get_buffer (vm, bi2);
+          b3 = vlib_get_buffer (vm, bi3);
+
+	  u8 *ptr0 = vlib_buffer_get_current (b0);
+          u8 *ptr1 = vlib_buffer_get_current (b1);
+          u8 *ptr2 = vlib_buffer_get_current (b2);
+          u8 *ptr3 = vlib_buffer_get_current (b3);
+	  u8 v0 = *ptr0 & 0xf0;
+	  u8 v1 = *ptr1 & 0xf0;
+	  u8 v2 = *ptr2 & 0xf0;
+	  u8 v3 = *ptr3 & 0xf0;
+
+          u8 advance = sizeof(ip4_header_t) + sizeof(udp_header_t);
+
+          vlib_buffer_advance(b0, -advance);
+          vlib_buffer_advance(b1, -advance);
+          vlib_buffer_advance(b2, -advance);
+          vlib_buffer_advance(b3, -advance);
+
+          u8 *outer_ptr0 = vlib_buffer_get_current (b0);
+          u8 *outer_ptr1 = vlib_buffer_get_current (b1);
+          u8 *outer_ptr2 = vlib_buffer_get_current (b2);
+          u8 *outer_ptr3 = vlib_buffer_get_current (b3);
+          u8 outer_v0 = *outer_ptr0 & 0xf0;
+	  u8 outer_v1 = *outer_ptr1 & 0xf0;
+	  u8 outer_v2 = *outer_ptr2 & 0xf0;
+	  u8 outer_v3 = *outer_ptr3 & 0xf0;
+
+          ip46_address_t src0 = {0};
+          ip46_address_t src1 = {0};
+          ip46_address_t src2 = {0};
+          ip46_address_t src3 = {0};
+
+          ip46_address_t dst0 = {0};
+          ip46_address_t dst1 = {0};
+          ip46_address_t dst2 = {0};
+          ip46_address_t dst3 = {0};
+
+          udp_header_t * udp0 = NULL;
+          udp_header_t * udp1 = NULL;
+          udp_header_t * udp2 = NULL;
+          udp_header_t * udp3 = NULL;
+
+          ip46_address_set_ip4(&src0, &((ip4_header_t *)outer_ptr0)->src_address);
+          ip46_address_set_ip4(&dst0, &((ip4_header_t *)outer_ptr0)->dst_address);
+          udp0 = (udp_header_t *)(outer_ptr0 + sizeof(ip4_header_t));
+          next0 = v0 == 0x40? UDP4_DECAP_NEXT_LOOKUP_IP4 : UDP4_DECAP_NEXT_LOOKUP_IP6;
+
+          ip46_address_set_ip4(&src1, &((ip4_header_t *)outer_ptr1)->src_address);
+          ip46_address_set_ip4(&dst1, &((ip4_header_t *)outer_ptr1)->dst_address);
+          udp1 = (udp_header_t *)(outer_ptr1 + sizeof(ip4_header_t));
+          next1 = v1 == 0x40? UDP4_DECAP_NEXT_LOOKUP_IP4 : UDP4_DECAP_NEXT_LOOKUP_IP6;
+
+          ip46_address_set_ip4(&src2, &((ip4_header_t *)outer_ptr2)->src_address);
+          ip46_address_set_ip4(&dst2, &((ip4_header_t *)outer_ptr2)->dst_address);
+          udp2 = (udp_header_t *)(outer_ptr2 + sizeof(ip4_header_t));
+          next2 = v2 == 0x40? UDP4_DECAP_NEXT_LOOKUP_IP4 : UDP4_DECAP_NEXT_LOOKUP_IP6;
+
+          ip46_address_set_ip4(&src3, &((ip4_header_t *)outer_ptr3)->src_address);
+          ip46_address_set_ip4(&dst3, &((ip4_header_t *)outer_ptr3)->dst_address);
+          udp3 = (udp_header_t *)(outer_ptr3 + sizeof(ip4_header_t));
+          next3 = v3 == 0x40? UDP4_DECAP_NEXT_LOOKUP_IP4 : UDP4_DECAP_NEXT_LOOKUP_IP6;
+
+          hicn_buffer_t *hicnb0, *hicnb1, *hicnb2, *hicnb3;
+          hicnb0 = hicn_get_buffer(b0);
+          hicnb1 = hicn_get_buffer(b1);
+          hicnb2 = hicn_get_buffer(b2);
+          hicnb3 = hicn_get_buffer(b3);
+
+
+          /* Udp encap-decap tunnels have dst and src addresses and port swapped */
+          vnet_buffer (b0)->ip.adj_index[VLIB_RX] = udp_tunnel_get(&dst0, &src0, udp0->dst_port, udp0->src_port);
+          vnet_buffer (b1)->ip.adj_index[VLIB_RX] = udp_tunnel_get(&dst1, &src1, udp1->dst_port, udp1->src_port);
+          vnet_buffer (b2)->ip.adj_index[VLIB_RX] = udp_tunnel_get(&dst2, &src2, udp2->dst_port, udp2->src_port);
+          vnet_buffer (b3)->ip.adj_index[VLIB_RX] = udp_tunnel_get(&dst3, &src3, udp3->dst_port, udp3->src_port);
+
+          if (vnet_buffer (b0)->ip.adj_index[VLIB_RX] !=
+              UDP_TUNNEL_INVALID)
+            hicnb0->flags |= (outer_v0 == 0x40? HICN_BUFFER_FLAGS_FROM_UDP4_TUNNEL : HICN_BUFFER_FLAGS_FROM_UDP6_TUNNEL);
+
+          if (vnet_buffer (b1)->ip.adj_index[VLIB_RX] !=
+              UDP_TUNNEL_INVALID)
+            hicnb1->flags |= (outer_v1 == 0x40? HICN_BUFFER_FLAGS_FROM_UDP4_TUNNEL : HICN_BUFFER_FLAGS_FROM_UDP6_TUNNEL);
+
+          if (vnet_buffer (b2)->ip.adj_index[VLIB_RX] !=
+              UDP_TUNNEL_INVALID)
+            hicnb2->flags |= (outer_v2 == 0x40? HICN_BUFFER_FLAGS_FROM_UDP4_TUNNEL : HICN_BUFFER_FLAGS_FROM_UDP6_TUNNEL);
+
+          if (vnet_buffer (b3)->ip.adj_index[VLIB_RX] !=
+              UDP_TUNNEL_INVALID)
+            hicnb3->flags |= (outer_v3 == 0x40? HICN_BUFFER_FLAGS_FROM_UDP4_TUNNEL : HICN_BUFFER_FLAGS_FROM_UDP6_TUNNEL);
+
+          udp_decap_trace_buffer (vm, node, 1, b0);
+          udp_decap_trace_buffer (vm, node, 1, b1);
+          udp_decap_trace_buffer (vm, node, 1, b2);
+          udp_decap_trace_buffer (vm, node, 1, b3);
+
+          vlib_buffer_advance(b0, advance);
+          vlib_buffer_advance(b1, advance);
+          vlib_buffer_advance(b2, advance);
+          vlib_buffer_advance(b3, advance);
+
+          vlib_validate_buffer_enqueue_x4 (vm, node, next_index, to_next,
+					   n_left_to_next, bi0, bi1, bi2, bi3,
+					   next0, next1, next2, next3);
+	}
+
+      /* Dual loop, X1 */
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  vlib_buffer_t *b0;
+	  u32 bi0;
+          /* udp_encap_t *udp_tunnel0 = NULL; */
+	  u32 next0;
+
+	  if (n_left_from > 1)
+	    {
+	      vlib_buffer_t *b1;
+	      b1 = vlib_get_buffer (vm, from[1]);
+	      CLIB_PREFETCH (b1, CLIB_CACHE_LINE_BYTES, STORE);
+	    }
+
+	  bi0 = from[0];
+	  from += 1;
+	  n_left_from -= 1;
+	  to_next[0] = bi0;
+	  to_next += 1;
+	  n_left_to_next -= 1;
+
+          b0 = vlib_get_buffer (vm, bi0);
+
+	  u8 *ptr0 = vlib_buffer_get_current (b0);
+	  u8 v0 = *ptr0 & 0xf0;
+
+          u8 advance = sizeof(ip4_header_t) + sizeof(udp_header_t);;
+
+          vlib_buffer_advance(b0, -advance);
+
+          u8 *outer_ptr0 = vlib_buffer_get_current (b0);
+          u8 outer_v0 = *outer_ptr0 & 0xf0;
+
+          ip46_address_t src0 = {0};
+          ip46_address_t dst0 = {0};
+          udp_header_t * udp0 = NULL;
+
+          ip46_address_set_ip4(&src0, &((ip4_header_t *)outer_ptr0)->src_address);
+          ip46_address_set_ip4(&dst0, &((ip4_header_t *)outer_ptr0)->dst_address);
+          udp0 = (udp_header_t *)(outer_ptr0 + sizeof(ip4_header_t));
+          next0 = v0 == 0x40 ? UDP4_DECAP_NEXT_LOOKUP_IP4: UDP4_DECAP_NEXT_LOOKUP_IP6;
+
+          hicn_buffer_t *hicnb0 = hicn_get_buffer(b0);
+
+          vnet_buffer (b0)->ip.adj_index[VLIB_RX] = udp_tunnel_get(&dst0, &src0, udp0->dst_port, udp0->src_port);
+
+          if (vnet_buffer (b0)->ip.adj_index[VLIB_RX] !=
+              UDP_TUNNEL_INVALID)
+            hicnb0->flags |= (outer_v0 == 0x40 ? HICN_BUFFER_FLAGS_FROM_UDP4_TUNNEL : HICN_BUFFER_FLAGS_FROM_UDP6_TUNNEL);
+
+          udp_decap_trace_buffer (vm, node, 1, b0);
+
+          vlib_buffer_advance(b0, advance);
+
+          vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
+                                           n_left_to_next, bi0, next0);
+
+	}
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  return (frame->n_vectors);
+}
+
+
+/*
+ * Node registration for the interest forwarder node
+ */
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE(udp4_decap_node) =
+{
+  .function = udp4_decap_node_fn,
+  .name = "udp4-decap",
+  .vector_size = sizeof(u32),
+  .format_trace = format_udp_decap_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .n_errors = ARRAY_LEN(udp_decap_error_strings),
+  .error_strings = udp_decap_error_strings,
+  .n_next_nodes = UDP4_DECAP_N_NEXT,
+  /* edit / add dispositions here */
+  .next_nodes =
+  {
+    [UDP4_DECAP_NEXT_LOOKUP_IP4] = "ip4-lookup",
+    [UDP4_DECAP_NEXT_LOOKUP_IP6] = "ip6-lookup"
+  },
+};
+/* *INDENT-ON* */
+
+static uword
+udp6_decap_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+                   vlib_frame_t * frame)
+{
+  u32 n_left_from, *from, *to_next, next_index;
+
+  from = vlib_frame_vector_args (frame);
+  n_left_from = frame->n_vectors;
+  next_index = node->cached_next_index;
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+
+      /* Dual loop, X2 */
+      while (n_left_from >= 8 && n_left_to_next >= 4)
+	{
+          vlib_buffer_t *b0, *b1, *b2, *b3;
+	  u32 bi0, bi1, bi2, bi3;
+	  u32 next0, next1, next2, next3;
+
+          {
+	    vlib_buffer_t *b4, *b5, *b6, *b7;
+	    b4 = vlib_get_buffer (vm, from[4]);
+	    b5 = vlib_get_buffer (vm, from[5]);
+	    b6 = vlib_get_buffer (vm, from[6]);
+	    b7 = vlib_get_buffer (vm, from[7]);
+	    CLIB_PREFETCH (b4, CLIB_CACHE_LINE_BYTES, STORE);
+	    CLIB_PREFETCH (b5, CLIB_CACHE_LINE_BYTES, STORE);
+	    CLIB_PREFETCH (b6, CLIB_CACHE_LINE_BYTES, STORE);
+	    CLIB_PREFETCH (b7, CLIB_CACHE_LINE_BYTES, STORE);
+	  }
+
+	  bi0 = from[0];
+	  bi1 = from[1];
+	  bi2 = from[2];
+	  bi3 = from[3];
+
+	  from += 4;
+	  n_left_from -= 4;
+	  to_next[0] = bi0;
+	  to_next[1] = bi1;
+	  to_next[2] = bi2;
+	  to_next[3] = bi3;
+
+	  to_next += 4;
+	  n_left_to_next -= 4;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+	  b1 = vlib_get_buffer (vm, bi1);
+	  b2 = vlib_get_buffer (vm, bi2);
+	  b3 = vlib_get_buffer (vm, bi3);
+
+	  u8 *ptr0 = vlib_buffer_get_current (b0);
+          u8 *ptr1 = vlib_buffer_get_current (b1);
+          u8 *ptr2 = vlib_buffer_get_current (b2);
+          u8 *ptr3 = vlib_buffer_get_current (b3);
+	  u8 v0 = *ptr0 & 0xf0;
+	  u8 v1 = *ptr1 & 0xf0;
+	  u8 v2 = *ptr2 & 0xf0;
+	  u8 v3 = *ptr3 & 0xf0;
+
+          u8 advance = sizeof(ip6_header_t) + sizeof(udp_header_t);
+
+          vlib_buffer_advance(b0, -advance);
+          vlib_buffer_advance(b1, -advance);
+          vlib_buffer_advance(b2, -advance);
+          vlib_buffer_advance(b3, -advance);
+
+          u8 *outer_ptr0 = vlib_buffer_get_current (b0);
+          u8 *outer_ptr1 = vlib_buffer_get_current (b1);
+          u8 *outer_ptr2 = vlib_buffer_get_current (b2);
+          u8 *outer_ptr3 = vlib_buffer_get_current (b3);
+          u8 outer_v0 = *outer_ptr0 & 0xf0;
+	  u8 outer_v1 = *outer_ptr1 & 0xf0;
+	  u8 outer_v2 = *outer_ptr2 & 0xf0;
+	  u8 outer_v3 = *outer_ptr3 & 0xf0;
+
+          ip46_address_t src0 = {0};
+          ip46_address_t src1 = {0};
+          ip46_address_t src2 = {0};
+          ip46_address_t src3 = {0};
+
+          ip46_address_t dst0 = {0};
+          ip46_address_t dst1 = {0};
+          ip46_address_t dst2 = {0};
+          ip46_address_t dst3 = {0};
+
+          udp_header_t * udp0 = NULL;
+          udp_header_t * udp1 = NULL;
+          udp_header_t * udp2 = NULL;
+          udp_header_t * udp3 = NULL;
+
+          ip46_address_set_ip6(&src0, &((ip6_header_t *)outer_ptr0)->src_address);
+          ip46_address_set_ip6(&dst0, &((ip6_header_t *)outer_ptr0)->dst_address);
+          udp0 = (udp_header_t *)(outer_ptr0 + sizeof(ip6_header_t));
+          next0 = v0 == 0x40 ? UDP6_DECAP_NEXT_LOOKUP_IP4 : UDP6_DECAP_NEXT_LOOKUP_IP6;
+
+          ip46_address_set_ip6(&src1, &((ip6_header_t *)outer_ptr1)->src_address);
+          ip46_address_set_ip6(&dst1, &((ip6_header_t *)outer_ptr1)->dst_address);
+          udp1 = (udp_header_t *)(outer_ptr1 + sizeof(ip6_header_t));
+          next1 = v1 == 0x40 ? UDP6_DECAP_NEXT_LOOKUP_IP4 : UDP6_DECAP_NEXT_LOOKUP_IP6;
+
+          ip46_address_set_ip6(&src2, &((ip6_header_t *)outer_ptr2)->src_address);
+          ip46_address_set_ip6(&dst2, &((ip6_header_t *)outer_ptr2)->dst_address);
+          udp2 = (udp_header_t *)(outer_ptr2 + sizeof(ip6_header_t));
+          next2 = v2 == 0x40 ? UDP6_DECAP_NEXT_LOOKUP_IP4 : UDP6_DECAP_NEXT_LOOKUP_IP6;
+
+          ip46_address_set_ip6(&src3, &((ip6_header_t *)outer_ptr3)->src_address);
+          ip46_address_set_ip6(&dst3, &((ip6_header_t *)outer_ptr3)->dst_address);
+          udp3 = (udp_header_t *)(outer_ptr3 + sizeof(ip6_header_t));
+          next3 = v3 == 0x40 ? UDP6_DECAP_NEXT_LOOKUP_IP4 : UDP6_DECAP_NEXT_LOOKUP_IP6;
+
+          hicn_buffer_t *hicnb0, *hicnb1, *hicnb2, *hicnb3;
+          hicnb0 = hicn_get_buffer(b0);
+          hicnb1 = hicn_get_buffer(b1);
+          hicnb2 = hicn_get_buffer(b2);
+          hicnb3 = hicn_get_buffer(b3);
+
+
+          /* Udp encap-decap tunnels have dst and src addresses and port swapped */
+          vnet_buffer (b0)->ip.adj_index[VLIB_RX] = udp_tunnel_get(&dst0, &src0, udp0->dst_port, udp0->src_port);
+          vnet_buffer (b1)->ip.adj_index[VLIB_RX] = udp_tunnel_get(&dst1, &src1, udp1->dst_port, udp1->src_port);
+          vnet_buffer (b2)->ip.adj_index[VLIB_RX] = udp_tunnel_get(&dst2, &src2, udp2->dst_port, udp2->src_port);
+          vnet_buffer (b3)->ip.adj_index[VLIB_RX] = udp_tunnel_get(&dst3, &src3, udp3->dst_port, udp3->src_port);
+
+          if (vnet_buffer (b0)->ip.adj_index[VLIB_RX] !=
+              UDP_TUNNEL_INVALID)
+            hicnb0->flags |= (outer_v0 == 0x40? HICN_BUFFER_FLAGS_FROM_UDP4_TUNNEL : HICN_BUFFER_FLAGS_FROM_UDP6_TUNNEL);
+
+          if (vnet_buffer (b1)->ip.adj_index[VLIB_RX] !=
+              UDP_TUNNEL_INVALID)
+            hicnb1->flags |= (outer_v1 == 0x40? HICN_BUFFER_FLAGS_FROM_UDP4_TUNNEL : HICN_BUFFER_FLAGS_FROM_UDP6_TUNNEL);
+
+          if (vnet_buffer (b2)->ip.adj_index[VLIB_RX] !=
+              UDP_TUNNEL_INVALID)
+            hicnb2->flags |= (outer_v2 == 0x40? HICN_BUFFER_FLAGS_FROM_UDP4_TUNNEL : HICN_BUFFER_FLAGS_FROM_UDP6_TUNNEL);
+
+          if (vnet_buffer (b3)->ip.adj_index[VLIB_RX] !=
+              UDP_TUNNEL_INVALID)
+            hicnb3->flags |= (outer_v3 == 0x40? HICN_BUFFER_FLAGS_FROM_UDP4_TUNNEL : HICN_BUFFER_FLAGS_FROM_UDP6_TUNNEL);
+
+          udp_decap_trace_buffer (vm, node, 0, b0);
+          udp_decap_trace_buffer (vm, node, 0, b1);
+          udp_decap_trace_buffer (vm, node, 0, b2);
+          udp_decap_trace_buffer (vm, node, 0, b3);
+
+          vlib_buffer_advance(b0, advance);
+          vlib_buffer_advance(b1, advance);
+          vlib_buffer_advance(b2, advance);
+          vlib_buffer_advance(b3, advance);
+
+          vlib_validate_buffer_enqueue_x4 (vm, node, next_index, to_next,
+					   n_left_to_next, bi0, bi1, bi2, bi3,
+					   next0, next1, next2, next3);
+	}
+
+      /* Dual loop, X1 */
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  vlib_buffer_t *b0;
+	  u32 bi0;
+          /* udp_encap_t *udp_tunnel0 = NULL; */
+	  u32 next0;
+
+	  if (n_left_from > 1)
+	    {
+	      vlib_buffer_t *b1;
+	      b1 = vlib_get_buffer (vm, from[1]);
+	      CLIB_PREFETCH (b1, CLIB_CACHE_LINE_BYTES, STORE);
+	    }
+
+	  bi0 = from[0];
+	  from += 1;
+	  n_left_from -= 1;
+	  to_next[0] = bi0;
+	  to_next += 1;
+	  n_left_to_next -= 1;
+
+          b0 = vlib_get_buffer (vm, bi0);
+
+	  u8 *ptr0 = vlib_buffer_get_current (b0);
+	  u8 v0 = *ptr0 & 0xf0;
+
+          u8 advance = sizeof(ip6_header_t) + sizeof(udp_header_t);
+
+          vlib_buffer_advance(b0, -advance);
+
+          u8 *outer_ptr0 = vlib_buffer_get_current (b0);
+          u8 outer_v0 = *outer_ptr0 & 0xf0;
+
+          ip46_address_t src0 = {0};
+          ip46_address_t dst0 = {0};
+          udp_header_t * udp0 = NULL;
+
+          ip46_address_set_ip6(&src0, &((ip6_header_t *)outer_ptr0)->src_address);
+          ip46_address_set_ip6(&dst0, &((ip6_header_t *)outer_ptr0)->dst_address);
+          udp0 = (udp_header_t *)(outer_ptr0 + sizeof(ip6_header_t));
+          next0 = v0 == 0x40? UDP6_DECAP_NEXT_LOOKUP_IP4 : UDP6_DECAP_NEXT_LOOKUP_IP6;
+
+          hicn_buffer_t *hicnb0 = hicn_get_buffer(b0);
+
+          vnet_buffer (b0)->ip.adj_index[VLIB_RX] = udp_tunnel_get(&dst0, &src0, udp0->dst_port, udp0->src_port);
+
+          if (vnet_buffer (b0)->ip.adj_index[VLIB_RX] !=
+              UDP_TUNNEL_INVALID)
+            hicnb0->flags |= (outer_v0 == 0x40? HICN_BUFFER_FLAGS_FROM_UDP4_TUNNEL : HICN_BUFFER_FLAGS_FROM_UDP6_TUNNEL);
+
+          udp_decap_trace_buffer (vm, node, 0, b0);
+
+          vlib_buffer_advance(b0, advance);
+
+          vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
+                                           n_left_to_next, bi0, next0);
+
+	}
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  return (frame->n_vectors);
+}
+
+
+/*
+ * Node registration for the interest forwarder node
+ */
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE(udp6_decap_node) =
+{
+  .function = udp6_decap_node_fn,
+  .name = "udp6-decap",
+  .vector_size = sizeof(u32),
+  .format_trace = format_udp_decap_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .n_errors = ARRAY_LEN(udp_decap_error_strings),
+  .error_strings = udp_decap_error_strings,
+  .n_next_nodes = UDP6_DECAP_N_NEXT,
+  /* edit / add dispositions here */
+  .next_nodes =
+  {
+    [UDP6_DECAP_NEXT_LOOKUP_IP4] = "ip4-lookup",
+    [UDP6_DECAP_NEXT_LOOKUP_IP6] = "ip6-lookup"
+  },
+};
+/* *INDENT-ON* */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables:
+ * eval: (c-set-style "gnu")
+ * End:
+ */
diff --git a/hicn-plugin/src/udp_tunnels/udp_tunnel.c b/hicn-plugin/src/udp_tunnels/udp_tunnel.c
new file mode 100644
index 000000000..872e4cd82
--- /dev/null
+++ b/hicn-plugin/src/udp_tunnels/udp_tunnel.c
@@ -0,0 +1,281 @@
+/*
+ * Copyright (c) 2020 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#include <vlib/vlib.h>
+#include <vnet/vnet.h>
+#include <vppinfra/bihash_40_8.h>
+#include <vnet/fib/fib_table.h>
+
+#include "../error.h"
+#include "../strategy_dpo_ctx.h"
+#include "udp_tunnel.h"
+
+clib_bihash_40_8_t udp_tunnels_hashtb;
+dpo_type_t dpo_type_udp_ip4;
+dpo_type_t dpo_type_udp_ip6;
+
+u32 udp_tunnel_add (fib_protocol_t proto,
+                    index_t fib_index,
+                    const ip46_address_t * src_ip,
+                    const ip46_address_t * dst_ip,
+                    u16 src_port,
+                    u16 dst_port,
+                    udp_encap_fixup_flags_t flags)
+{
+  vlib_main_t *vm = vlib_get_main();
+  clib_bihash_kv_40_8_t kv;
+  clib_memcpy(&kv.key[0], src_ip, sizeof(ip46_address_t));
+  clib_memcpy(&kv.key[2], dst_ip, sizeof(ip46_address_t));
+  kv.key[4] = (clib_host_to_net_u16(src_port) << 16) + clib_host_to_net_u16(dst_port);
+
+  clib_bihash_kv_40_8_t value;
+  int rv = clib_bihash_search_40_8 (&udp_tunnels_hashtb, &kv, &value);
+
+  if (rv != 0)
+    {
+      u32 uei = udp_encap_add_and_lock(proto, fib_index, src_ip, dst_ip, src_port, dst_port, flags);
+      kv.value = uei;
+      clib_bihash_add_del_40_8(&udp_tunnels_hashtb, &kv, 1);
+      value.value = kv.value;
+      if (proto == FIB_PROTOCOL_IP4)
+        {
+          udp_register_dst_port(vm, src_port, udp4_decap_node.index, 1);
+        }
+      else
+        {
+          udp_register_dst_port(vm, src_port, udp6_decap_node.index, 0);
+        }
+    }
+
+  return value.value;
+}
+
+void udp_tunnel_add_existing (index_t uei, dpo_proto_t proto)
+{
+  vlib_main_t *vm = vlib_get_main();
+  udp_encap_t * udp_encap = udp_encap_get(uei);
+  clib_bihash_kv_40_8_t kv;
+
+  ip46_address_t src = {0};
+  ip46_address_t dst = {0};
+  u16 src_port = 0, dst_port = 0;
+
+  switch (proto)
+    {
+    case DPO_PROTO_IP4:
+      ip46_address_set_ip4(&src, &(udp_encap->ue_hdrs.ip4.ue_ip4.src_address));
+      ip46_address_set_ip4(&dst, &(udp_encap->ue_hdrs.ip4.ue_ip4.dst_address));
+      src_port = udp_encap->ue_hdrs.ip4.ue_udp.src_port;
+      dst_port = udp_encap->ue_hdrs.ip4.ue_udp.dst_port;
+      break;
+    case DPO_PROTO_IP6:
+      ip46_address_set_ip6(&src, &(udp_encap->ue_hdrs.ip6.ue_ip6.src_address));
+      ip46_address_set_ip6(&dst, &(udp_encap->ue_hdrs.ip6.ue_ip6.dst_address));
+      src_port = udp_encap->ue_hdrs.ip6.ue_udp.src_port;
+      dst_port = udp_encap->ue_hdrs.ip6.ue_udp.dst_port;
+      break;
+    default:
+      break;
+    }
+
+  clib_memcpy(&kv.key[0], &src, sizeof(ip46_address_t));
+  clib_memcpy(&kv.key[2], &dst, sizeof(ip46_address_t));
+  kv.key[4] = (src_port << 16) + dst_port ;
+  kv.value = uei;
+
+  clib_bihash_add_del_40_8(&udp_tunnels_hashtb, &kv, 1);
+
+  if (proto == DPO_PROTO_IP4)
+    {
+      udp_register_dst_port(vm, clib_net_to_host_u16(src_port), udp4_decap_node.index, 1);
+    }
+  else
+    {
+      udp_register_dst_port(vm, clib_net_to_host_u16(src_port), udp6_decap_node.index, 0);
+    }
+}
+
+int udp_tunnel_del (fib_protocol_t proto,
+                    index_t fib_index,
+                    const ip46_address_t * src_ip,
+                    const ip46_address_t * dst_ip,
+                    u16 src_port,
+                    u16 dst_port,
+                    udp_encap_fixup_flags_t flags)
+{
+  clib_bihash_kv_40_8_t kv;
+  clib_memcpy(&kv.key[0], src_ip, sizeof(ip46_address_t));
+  clib_memcpy(&kv.key[2], dst_ip, sizeof(ip46_address_t));
+  kv.key[4] = (clib_host_to_net_u16(src_port) << 16) + clib_host_to_net_u16(dst_port);
+
+  clib_bihash_kv_40_8_t value;
+  int ret = clib_bihash_search_40_8 (&udp_tunnels_hashtb, &kv, &value);
+
+  if (ret == 0)
+    {
+      udp_encap_unlock((u32)value.value);
+      clib_bihash_add_del_40_8(&udp_tunnels_hashtb, &kv, 0);
+      ret = HICN_ERROR_NONE;
+    }
+  else
+    {
+      ret = HICN_ERROR_UDP_TUNNEL_NOT_FOUND;
+    }
+
+  return ret;
+}
+
+u32 udp_tunnel_get(const ip46_address_t * src_ip,
+                   const ip46_address_t * dst_ip,
+                   u16 src_port,
+                   u16 dst_port)
+{
+  clib_bihash_kv_40_8_t kv;
+  clib_memcpy(&kv.key[0], src_ip, sizeof(ip46_address_t));
+  clib_memcpy(&kv.key[2], dst_ip, sizeof(ip46_address_t));
+  kv.key[4] = (src_port << 16) + dst_port;
+
+  clib_bihash_kv_40_8_t value;
+  int ret = clib_bihash_search_40_8 (&udp_tunnels_hashtb, &kv, &value);
+
+  return ret == 0 ? (u32)value.value : UDP_TUNNEL_INVALID;
+}
+
+
+void udp_tunnel_init()
+{
+  clib_bihash_init_40_8(&udp_tunnels_hashtb, "udp encap table",
+                        2048, 256 << 20);
+
+  /*
+   * Udp encap does not expose the dpo type when it registers.
+   * In the following we understand what is the dpo type for a udp_encap dpo.
+   */
+  ip46_address_t src = {0};
+  ip46_address_t dst = {0};
+
+  src.ip6.as_u8[15] = 1;
+  dst.ip6.as_u8[15] = 2;
+
+  u32 fib_index = fib_table_find (FIB_PROTOCOL_IP6, HICN_FIB_TABLE);
+  u32 uei = udp_encap_add_and_lock(FIB_PROTOCOL_IP6, fib_index, &src, &dst, 4444, 4444, UDP_ENCAP_FIXUP_NONE);
+
+  dpo_id_t temp = DPO_INVALID;
+  udp_encap_contribute_forwarding(uei, DPO_PROTO_IP6, &temp);
+  dpo_type_udp_ip6 = temp.dpoi_type;
+  udp_encap_unlock(uei);
+
+  dpo_id_t temp2 = DPO_INVALID;
+  fib_index = fib_table_find (FIB_PROTOCOL_IP4, HICN_FIB_TABLE);
+  uei = udp_encap_add_and_lock(FIB_PROTOCOL_IP4, fib_index, &src, &dst, 4444, 4444, UDP_ENCAP_FIXUP_NONE);
+  udp_encap_contribute_forwarding(uei, DPO_PROTO_IP4, &temp2);
+  dpo_type_udp_ip4 = temp2.dpoi_type;
+  udp_encap_unlock(uei);
+}
+
+static clib_error_t *
+udp_tunnel_command_fn (vlib_main_t * vm,
+			       unformat_input_t * main_input,
+			       vlib_cli_command_t * cmd)
+{
+  unformat_input_t _line_input, *line_input = &_line_input;
+  clib_error_t *error = NULL;
+  ip46_address_t src_ip = {0}, dst_ip = {0};
+  u32 table_id, src_port, dst_port;
+  fib_protocol_t fproto;
+  u8 is_del;
+  index_t uei;
+
+  is_del = 0;
+  fproto = FIB_PROTOCOL_MAX;
+  uei = ~0;
+  table_id = HICN_FIB_TABLE;
+
+  /* Get a line of input. */
+  if (unformat_user (main_input, unformat_line_input, line_input))
+    {
+      while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
+	{
+          if (unformat (line_input, "index %d", &uei))
+            ;
+          else if (unformat (line_input, "add"))
+            is_del = 0;
+          else if (unformat (line_input, "del"))
+            is_del = 1;
+          else if (unformat (line_input, "%U %U",
+                             unformat_ip4_address,
+                             &src_ip.ip4, unformat_ip4_address, &dst_ip.ip4))
+            fproto = FIB_PROTOCOL_IP4;
+          else if (unformat (line_input, "%U %U",
+                             unformat_ip6_address,
+                             &src_ip.ip6, unformat_ip6_address, &dst_ip.ip6))
+            fproto = FIB_PROTOCOL_IP6;
+          else if (unformat (line_input, "%d %d", &src_port, &dst_port))
+            ;
+          else if (unformat (line_input, "table-id %d", &table_id))
+            ;
+          else
+            {
+              error = unformat_parse_error (line_input);
+              goto done;
+            }
+	}
+    }
+
+  index_t fib_index = fib_table_find (fproto, table_id);
+  if (~0 == fib_index)
+    {
+      error = clib_error_return (0, "Nonexistent table id %d", table_id);
+      goto done;
+    }
+
+  if (!is_del && fproto != FIB_PROTOCOL_MAX)
+    {
+      uei = udp_tunnel_add(fproto, fib_index, &src_ip, &dst_ip, src_port, dst_port, UDP_ENCAP_FIXUP_NONE);
+
+      vlib_cli_output (vm, "udp-encap: %d\n", uei);
+    }
+  else if (is_del)
+    {
+      int ret = udp_tunnel_del(fproto, fib_index, &src_ip, &dst_ip, src_port, dst_port, UDP_ENCAP_FIXUP_NONE);
+      error = (ret == HICN_ERROR_NONE) ? 0 : clib_error_return (0, "%s\n",
+                                                                get_error_string
+                                                                (ret));
+    }
+  else
+    {
+      error = clib_error_return (0, "specify some IP addresses");
+    }
+
+ done:
+  unformat_free (line_input);
+  return error;
+
+}
+
+/* *INDENT-OFF* */
+VLIB_CLI_COMMAND (udp_tunnel_command, static) =
+  {
+   .path = "udp tunnel",
+   .short_help = "udp tunnel [add/del] src_address dst_address src_port dst_port",
+   .function = udp_tunnel_command_fn,
+  };
+/* *INDENT-ON* */
+
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables: eval: (c-set-style "gnu") End:
+ */
diff --git a/hicn-plugin/src/udp_tunnels/udp_tunnel.h b/hicn-plugin/src/udp_tunnels/udp_tunnel.h
new file mode 100644
index 000000000..8f38a47e4
--- /dev/null
+++ b/hicn-plugin/src/udp_tunnels/udp_tunnel.h
@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2020 Cisco and/or its affiliates.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at:
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __UDP_TUNNEL__
+#define __UDP_TUNNEL__
+
+#include <vlib/vlib.h>
+#include <vppinfra/error.h>
+#include <vnet/udp/udp_encap.h>
+
+#define UDP_TUNNEL_INVALID ~0
+
+extern dpo_type_t dpo_type_udp_ip4;
+extern dpo_type_t dpo_type_udp_ip6;
+
+extern vlib_node_registration_t udp4_decap_node;
+extern vlib_node_registration_t udp6_decap_node;
+
+
+u32 udp_tunnel_add (fib_protocol_t proto,
+                    index_t fib_index,
+                    const ip46_address_t * src_ip,
+                    const ip46_address_t * dst_ip,
+                    u16 src_port,
+                    u16 dst_port,
+                    udp_encap_fixup_flags_t flags);
+
+u32 udp_tunnel_get(const ip46_address_t * src_ip,
+                   const ip46_address_t * dst_ip,
+                   u16 src_port,
+                   u16 dst_port);
+
+int udp_tunnel_del (fib_protocol_t proto,
+                    index_t fib_index,
+                    const ip46_address_t * src_ip,
+                    const ip46_address_t * dst_ip,
+                    u16 src_port,
+                    u16 dst_port,
+                    udp_encap_fixup_flags_t flags);
+
+void udp_tunnel_add_existing (index_t uei, dpo_proto_t proto);
+
+void udp_tunnel_init();
+
+#endif