[HICN-574] Host stack plugin for VPP.

Signed-off-by: Mauro Sardara <msardara@cisco.com>
Change-Id: I8d8fdffef31a7013265d6529c5f52f3d5ec70d18
Signed-off-by: Mauro Sardara <msardara@cisco.com>
Signed-off-by: Mauro <you@example.com>
Signed-off-by: Mauro Sardara <msardara@cisco.com>

1 files changed, 620 insertions, 0 deletions

diff --git a/hicn-plugin/src/network/data_fwd_node.c b/hicn-plugin/src/network/data_fwd_node.c
new file mode 100644
index 000000000..c65b62454
--- /dev/null
+++ b/hicn-plugin/src/network/data_fwd_node.c
@@ -0,0 +1,620 @@
+/*
+ * Copyright (c) 2017-2020 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/dpo/dpo.h>
+
+#include "data_fwd.h"
+#include "mgmt.h"
+#include "parser.h"
+#include "infra.h"
+#include "strategy.h"
+#include "strategy_dpo_manager.h"
+#include "state.h"
+#include "error.h"
+
+/* Stats string values */
+static char *hicn_data_fwd_error_strings[] = {
+#define _(sym, string) string,
+  foreach_hicnfwd_error
+#undef _
+};
+
+/* Declarations */
+always_inline void
+drop_packet (vlib_main_t * vm, u32 bi0,
+	     u32 * n_left_to_next, u32 * next0, u32 ** to_next,
+	     u32 * next_index, vlib_node_runtime_t * node);
+
+always_inline int
+hicn_satisfy_faces (vlib_main_t * vm, u32 b0,
+		    hicn_pcs_entry_t * pitp, u32 * n_left_to_next,
+		    u32 ** to_next, u32 * next_index,
+		    vlib_node_runtime_t * node, u8 isv6,
+		    vl_api_hicn_api_node_stats_get_reply_t * stats);
+
+always_inline void
+clone_data_to_cs (vlib_main_t * vm, hicn_pit_cs_t * pitcs,
+		  hicn_pcs_entry_t * pitp, hicn_header_t * hicn0, f64 tnow,
+		  hicn_hash_node_t * nodep, vlib_buffer_t * b0,
+		  hicn_hash_entry_t * hash_entry, u64 name_hash,
+		  hicn_buffer_t * hicnb, const hicn_dpo_vft_t * dpo_vft,
+		  dpo_id_t * hicn_dpo_id, hicn_lifetime_t dmsg_lifetime);
+
+
+/* packet trace format function */
+always_inline u8 *hicn_data_fwd_format_trace (u8 * s, va_list * args);
+
+vlib_node_registration_t hicn_data_fwd_node;
+
+/*
+ * ICN forwarder node for interests: handling of Data delivered based on ACL.
+ * - 1 packet at a time - ipv4/tcp ipv6/tcp
+ */
+static uword
+hicn_data_node_fn (vlib_main_t * vm, vlib_node_runtime_t * node,
+		   vlib_frame_t * frame)
+{
+
+  u32 n_left_from, *from, *to_next;
+  hicn_data_fwd_next_t next_index;
+  hicn_pit_cs_t *pitcs = &hicn_main.pitcs;
+  vl_api_hicn_api_node_stats_get_reply_t stats = { 0 };
+  f64 tnow;
+  u32 data_received = 1;
+
+  from = vlib_frame_vector_args (frame);
+  n_left_from = frame->n_vectors;
+  next_index = node->cached_next_index;
+
+  /* Capture time in vpp terms */
+  tnow = vlib_time_now (vm);
+
+  while (n_left_from > 0)
+    {
+      u32 n_left_to_next;
+      vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next);
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  vlib_buffer_t *b0;
+	  u8 isv6;
+	  u8 *nameptr;
+	  u16 namelen;
+	  u32 bi0;
+	  u32 next0 = HICN_DATA_FWD_NEXT_ERROR_DROP;
+	  hicn_name_t name;
+	  hicn_header_t *hicn0;
+	  hicn_buffer_t *hicnb0;
+	  hicn_hash_node_t *node0;
+	  const hicn_strategy_vft_t *strategy_vft0;
+	  const hicn_dpo_vft_t *dpo_vft0;
+	  u8 dpo_ctx_id0;
+	  hicn_pcs_entry_t *pitp;
+	  hicn_hash_entry_t *hash_entry0;
+	  int ret = HICN_ERROR_NONE;
+
+	  /* Prefetch for next iteration. */
+	  if (n_left_from > 1)
+	    {
+	      vlib_buffer_t *b1;
+	      b1 = vlib_get_buffer (vm, from[1]);
+	      CLIB_PREFETCH (b1, 2 * CLIB_CACHE_LINE_BYTES, STORE);
+	      CLIB_PREFETCH (b1->data, CLIB_CACHE_LINE_BYTES, STORE);
+	    }
+	  /* Dequeue a packet buffer */
+	  /*
+	   * Do not copy the index in the next buffer, we'll do
+	   * it later. The packet might be cloned, so the buffer to move
+	   * to next must be the cloned one
+	   */
+	  bi0 = from[0];
+	  from += 1;
+	  n_left_from -= 1;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+
+	  /* Get hicn buffer and state */
+	  hicnb0 = hicn_get_buffer (b0);
+	  hicn_get_internal_state (hicnb0, pitcs, &node0, &strategy_vft0,
+				   &dpo_vft0, &dpo_ctx_id0, &hash_entry0);
+
+	  ret = hicn_data_parse_pkt (b0, &name, &namelen, &hicn0, &isv6);
+	  pitp = hicn_pit_get_data (node0);
+	  nameptr = (u8 *) (&name);
+
+	  if (PREDICT_FALSE
+	      (ret != HICN_ERROR_NONE
+	       || !hicn_node_compare (nameptr, namelen, node0)
+	       || (hash_entry0->he_flags & HICN_HASH_ENTRY_FLAG_CS_ENTRY)))
+	    {
+	      /*
+	       * Remove the lock acquired from
+	       * data_pcslookup node
+	       */
+	      dpo_id_t hicn_dpo_id0 = { dpo_vft0->hicn_dpo_get_type (), 0, 0,
+		dpo_ctx_id0
+	      };
+	      hicn_pcs_remove_lock (pitcs, &pitp, &node0, vm,
+				    hash_entry0, dpo_vft0, &hicn_dpo_id0);
+
+	      drop_packet (vm, bi0, &n_left_to_next, &next0, &to_next,
+			   &next_index, node);
+
+	      goto end_processing;
+	    }
+	  /*
+	   * Check if the hit is instead a collision in the
+	   * hash table. Unlikely to happen.
+	   */
+	  /*
+	   * there is no guarantee that the type of entry has
+	   * not changed from the lookup.
+	   */
+
+	  if (tnow > pitp->shared.expire_time
+	      || (hash_entry0->he_flags & HICN_HASH_ENTRY_FLAG_DELETED))
+	    {
+	      dpo_id_t hicn_dpo_id0 =
+		{ dpo_vft0->hicn_dpo_get_type (), 0, 0, dpo_ctx_id0 };
+	      hicn_pcs_delete (pitcs, &pitp, &node0, vm, hash_entry0,
+			       dpo_vft0, &hicn_dpo_id0);
+
+              drop_packet (vm, bi0, &n_left_to_next, &next0, &to_next,
+                           &next_index, node);
+	      stats.pit_expired_count++;
+
+	      if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) &&
+				 (b0->flags & VLIB_BUFFER_IS_TRACED)))
+		{
+		  hicn_data_fwd_trace_t *t =
+		    vlib_add_trace (vm, node, b0, sizeof (*t));
+		  t->pkt_type = HICN_PKT_TYPE_CONTENT;
+		  t->sw_if_index = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+		  t->next_index = next0;
+		  clib_memcpy (t->packet_data,
+			       vlib_buffer_get_current (b0),
+			       sizeof (t->packet_data));
+		}
+	    }
+	  else
+	    {
+	      ASSERT ((hash_entry0->he_flags & HICN_HASH_ENTRY_FLAG_DELETED)
+		      == 0);
+
+	      data_received++;
+	      /*
+	       * We do not check if the data is coming from
+	       * the outgoing interest face.
+	       */
+
+	      /* Prepare the buffer for the cloning */
+	      ret = hicn_satisfy_faces (vm, bi0, pitp, &n_left_to_next,
+					&to_next, &next_index, node,
+					isv6, &stats);
+
+	      dpo_id_t hicn_dpo_id0 = { dpo_vft0->hicn_dpo_get_type (), 0, 0,
+		dpo_ctx_id0
+	      };
+
+	      if (PREDICT_FALSE (ret != HICN_ERROR_NONE))
+		{
+		  hicn_pcs_pit_delete (pitcs, &pitp, &node0, vm,
+				       hash_entry0, dpo_vft0, &hicn_dpo_id0);
+		  continue;
+		}
+	      /*
+	       * Call the strategy callback since the
+	       * interest has been satisfied
+	       */
+	      strategy_vft0->hicn_receive_data (dpo_ctx_id0,
+						pitp->u.pit.pe_txnh);
+
+#if HICN_FEATURE_CS
+	      hicn_lifetime_t dmsg_lifetime;
+
+	      hicn_type_t type = hicnb0->type;
+	      hicn_ops_vft[type.l1]->get_lifetime (type, &hicn0->protocol,
+						   &dmsg_lifetime);
+
+	      if (dmsg_lifetime)
+		{
+		  /*
+		   * Clone data packet in the content store and
+		   * convert the PIT entry into a CS entry
+		   */
+		  clone_data_to_cs (vm, pitcs, pitp, hicn0, tnow, node0,
+				    b0, hash_entry0, hicnb0->name_hash,
+				    hicnb0, dpo_vft0, &hicn_dpo_id0,
+				    dmsg_lifetime);
+
+		  hicn_pcs_remove_lock (pitcs, &pitp, &node0, vm,
+					hash_entry0, NULL, NULL);
+		}
+	      else
+		{
+		  /*
+		   * If the packet is copied and not cloned, we need to free the vlib_buffer
+		   */
+		  if (hicnb0->flags & HICN_BUFFER_FLAGS_PKT_LESS_TWO_CL)
+		    {
+		      vlib_buffer_free_one (vm, bi0);
+		    }
+		  else
+		    {
+		      /*
+		       * Remove one reference as the buffer is no
+		       * longer in any frame. The vlib_buffer will be freed when
+		       * all its cloned vlib_buffer will be freed.
+		       */
+		      b0->ref_count--;
+		    }
+
+		  /* Delete the PIT entry */
+		  hicn_pcs_pit_delete (pitcs, &pitp, &node0, vm,
+				       hash_entry0, dpo_vft0, &hicn_dpo_id0);
+		}
+#else
+	      ASSERT (pitp == hicn_pit_get_data (node0));
+	      /*
+	       * If the packet is copied and not cloned, we need to free the vlib_buffer
+	       */
+	      if (hicnb0->flags & HICN_BUFFER_FLAGS_PKT_LESS_TWO_CL)
+		{
+		  vlib_buffer_free_one (vm, bi0);
+		}
+	      else
+		{
+		  /*
+		   * Remove one reference as the buffer is no
+		   * longer in any frame. The vlib_buffer will be freed when
+		   * all its cloned vlib_buffer will be freed.
+		   */
+		  b0->ref_count--;
+		}
+
+	      /* Delete the PIT entry */
+	      hicn_pcs_pit_delete (pitcs, &pitp, &node0, vm,
+				   hash_entry0, dpo_vft0, &hicn_dpo_id0);
+#endif
+	    }
+	end_processing:
+
+	  /* Incr packet counter */
+	  stats.pkts_processed += 1;
+	}
+
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+  u32 pit_int_count = hicn_pit_get_int_count (pitcs);
+  u32 pit_cs_count = hicn_pit_get_cs_count (pitcs);
+
+  vlib_node_increment_counter (vm, hicn_data_fwd_node.index,
+			       HICNFWD_ERROR_DATAS, stats.pkts_data_count);
+
+
+  update_node_counter (vm, hicn_data_fwd_node.index,
+		       HICNFWD_ERROR_INT_COUNT, pit_int_count);
+  update_node_counter (vm, hicn_data_fwd_node.index,
+		       HICNFWD_ERROR_CS_COUNT, pit_cs_count);
+  update_node_counter (vm, hicn_data_fwd_node.index,
+		       HICNFWD_ERROR_INTEREST_AGG_ENTRY,
+		       stats.pkts_data_count / data_received);
+
+  return (frame->n_vectors);
+}
+
+always_inline void
+drop_packet (vlib_main_t * vm, u32 bi0,
+	     u32 * n_left_to_next, u32 * next0, u32 ** to_next,
+	     u32 * next_index, vlib_node_runtime_t * node)
+{
+  *next0 = HICN_DATA_FWD_NEXT_ERROR_DROP;
+
+  (*to_next)[0] = bi0;
+  *to_next += 1;
+  *n_left_to_next -= 1;
+
+  vlib_validate_buffer_enqueue_x1 (vm, node, *next_index,
+				   *to_next, *n_left_to_next, bi0, *next0);
+}
+
+always_inline int
+hicn_satisfy_faces (vlib_main_t * vm, u32 bi0,
+		    hicn_pcs_entry_t * pitp, u32 * n_left_to_next,
+		    u32 ** to_next, u32 * next_index,
+		    vlib_node_runtime_t * node, u8 isv6,
+		    vl_api_hicn_api_node_stats_get_reply_t * stats)
+{
+  int found = 0;
+  int ret = HICN_ERROR_NONE;
+  u32 *clones = NULL, *header = NULL;
+  u32 n_left_from = 0;
+  u32 next0 = HICN_DATA_FWD_NEXT_ERROR_DROP, next1 =
+    HICN_DATA_FWD_NEXT_ERROR_DROP;
+  word buffer_advance = CLIB_CACHE_LINE_BYTES * 2;
+
+  /*
+   * We have a hard limit on the number of vlib_buffer that we can
+   * chain (no more than 256)
+   */
+  /*
+   * The first group of vlib_buffer can be directly cloned from b0. We
+   * need to be careful to clone it only 254 times as the buffer
+   * already has n_add_reds=1.
+   */
+  vec_alloc (clones, pitp->u.pit.faces.n_faces);
+  header = clones;
+
+  /* Clone bi0 */
+  vlib_buffer_t *b0 = vlib_get_buffer (vm, bi0);
+
+  hicn_buffer_t *hicnb = hicn_get_buffer (b0);
+
+  /*
+   * Mark the buffer as smaller than TWO_CL. It will be stored as is in the CS, without excluding
+   * the hicn_header. Cloning is not possible, it will be copied.
+   */
+  if (b0->current_length <= (buffer_advance + (CLIB_CACHE_LINE_BYTES * 2)))
+    {
+      /* In this case the packet is copied. We don't need to add a reference as no buffer are
+       * chained to it.
+       */
+      hicnb->flags |= HICN_BUFFER_FLAGS_PKT_LESS_TWO_CL;
+    }
+  else
+    {
+      /* Add one reference to maintain the buffer in the CS.
+       * b0->ref_count == 0 has two meaning: it has 1 buffer or no buffer chained to it.
+       * vlib_buffer_clone2 add a number of reference equalt to pitp->u.pit.faces.n_faces - 1
+       * as vlib_buffer_clone does. So after all the packet are forwarded the buffer stored in
+       * the CS will have ref_count == 0;
+       */
+      b0->ref_count++;
+    }
+
+  found = n_left_from =
+    vlib_buffer_clone2 (vm, bi0, clones, pitp->u.pit.faces.n_faces,
+			buffer_advance);
+
+  ASSERT (n_left_from == pitp->u.pit.faces.n_faces);
+
+  /* Index to iterate over the faces */
+  int i = 0;
+
+  while (n_left_from > 0)
+    {
+
+      //Dual loop, X2
+      while (n_left_from >= 4 && *n_left_to_next >= 2)
+	{
+	  vlib_buffer_t *h0, *h1;
+	  u32 hi0, hi1;
+	  hicn_face_id_t face0, face1;
+
+	  /* Prefetch for next iteration. */
+	  {
+	    vlib_buffer_t *h2, *h3;
+	    h2 = vlib_get_buffer (vm, clones[2]);
+	    h3 = vlib_get_buffer (vm, clones[3]);
+	    CLIB_PREFETCH (h2, 2 * CLIB_CACHE_LINE_BYTES, STORE);
+	    CLIB_PREFETCH (h3, 2 * CLIB_CACHE_LINE_BYTES, STORE);
+	  }
+
+	  face0 = hicn_face_db_get_dpo_face (i++, &pitp->u.pit.faces);
+	  face1 = hicn_face_db_get_dpo_face (i++, &pitp->u.pit.faces);
+
+	  h0 = vlib_get_buffer (vm, clones[0]);
+	  h1 = vlib_get_buffer (vm, clones[1]);
+
+	  (*to_next)[0] = hi0 = clones[0];
+	  (*to_next)[1] = hi1 = clones[1];
+	  *to_next += 2;
+	  *n_left_to_next -= 2;
+	  n_left_from -= 2;
+	  clones += 2;
+
+	  next0 = isv6 ? HICN_DATA_FWD_NEXT_IFACE6_OUT :
+            HICN_DATA_FWD_NEXT_IFACE4_OUT;
+	  next1 = isv6 ? HICN_DATA_FWD_NEXT_IFACE6_OUT :
+            HICN_DATA_FWD_NEXT_IFACE4_OUT;
+
+          vnet_buffer (h0)->ip.adj_index[VLIB_TX] = face0;
+	  vnet_buffer (h1)->ip.adj_index[VLIB_TX] = face1;
+
+	  stats->pkts_data_count += 2;
+
+	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) &&
+			     (h0->flags & VLIB_BUFFER_IS_TRACED)))
+	    {
+	      hicn_data_fwd_trace_t *t =
+		vlib_add_trace (vm, node, h0, sizeof (*t));
+	      t->pkt_type = HICN_PKT_TYPE_CONTENT;
+	      t->sw_if_index = vnet_buffer (h0)->sw_if_index[VLIB_RX];
+	      t->next_index = next0;
+	      clib_memcpy (t->packet_data,
+			   vlib_buffer_get_current (h0),
+			   sizeof (t->packet_data));
+	    }
+	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) &&
+			     (h1->flags & VLIB_BUFFER_IS_TRACED)))
+	    {
+	      hicn_data_fwd_trace_t *t =
+		vlib_add_trace (vm, node, h1, sizeof (*t));
+	      t->pkt_type = HICN_PKT_TYPE_CONTENT;
+	      t->sw_if_index = vnet_buffer (h1)->sw_if_index[VLIB_RX];
+	      t->next_index = next1;
+	      clib_memcpy (t->packet_data,
+			   vlib_buffer_get_current (h1),
+			   sizeof (t->packet_data));
+	    }
+	  vlib_validate_buffer_enqueue_x2 (vm, node, *next_index,
+					   (*to_next), *n_left_to_next,
+					   hi0, hi1, next0, next1);
+	}
+
+
+      while (n_left_from > 0 && *n_left_to_next > 0)
+	{
+	  vlib_buffer_t *h0;
+	  u32 hi0;
+	  hicn_face_id_t face0;
+
+	  face0 = hicn_face_db_get_dpo_face (i++, &pitp->u.pit.faces);
+
+	  h0 = vlib_get_buffer (vm, clones[0]);
+
+	  (*to_next)[0] = hi0 = clones[0];
+	  *to_next += 1;
+	  *n_left_to_next -= 1;
+	  n_left_from -= 1;
+	  clones += 1;
+
+	  next0 = isv6 ? HICN_DATA_FWD_NEXT_IFACE6_OUT :
+            HICN_DATA_FWD_NEXT_IFACE4_OUT;
+	  vnet_buffer (h0)->ip.adj_index[VLIB_TX] = face0;
+
+	  stats->pkts_data_count++;
+
+	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) &&
+			     (h0->flags & VLIB_BUFFER_IS_TRACED)))
+	    {
+	      hicn_data_fwd_trace_t *t =
+		vlib_add_trace (vm, node, h0, sizeof (*t));
+	      t->pkt_type = HICN_PKT_TYPE_CONTENT;
+	      t->sw_if_index = vnet_buffer (h0)->sw_if_index[VLIB_RX];
+	      t->next_index = next0;
+	      clib_memcpy (t->packet_data,
+			   vlib_buffer_get_current (h0),
+			   sizeof (t->packet_data));
+	    }
+	  /*
+	   * Verify speculative enqueue, maybe switch current
+	   * next frame
+	   */
+	  /*
+	   * Fix in case of a wrong speculation. Needed to
+	   * clone the data in the right frame
+	   */
+	  vlib_validate_buffer_enqueue_x1 (vm, node, *next_index,
+					   *to_next, *n_left_to_next,
+					   hi0, next0);
+
+	}
+
+      /* Ensure that there is space for the next clone (if any) */
+      if (PREDICT_FALSE (*n_left_to_next == 0))
+	{
+	  vlib_put_next_frame (vm, node, *next_index, *n_left_to_next);
+
+	  vlib_get_next_frame (vm, node, *next_index, *to_next,
+			       *n_left_to_next);
+	}
+    }
+
+  vec_free (header);
+
+  if (PREDICT_FALSE (!found))
+    {
+      ASSERT (0);
+      drop_packet (vm, bi0, n_left_to_next, &next0, to_next, next_index,
+		   node);
+      ret = HICN_ERROR_FACE_NOT_FOUND;
+    }
+  return ret;
+}
+
+always_inline void
+clone_data_to_cs (vlib_main_t * vm, hicn_pit_cs_t * pitcs,
+		  hicn_pcs_entry_t * pitp, hicn_header_t * hicn0, f64 tnow,
+		  hicn_hash_node_t * nodep, vlib_buffer_t * b0,
+		  hicn_hash_entry_t * hash_entry, u64 name_hash,
+		  hicn_buffer_t * hicnb, const hicn_dpo_vft_t * dpo_vft,
+		  dpo_id_t * hicn_dpo_id, hicn_lifetime_t dmsg_lifetime)
+{
+  /*
+   * At this point we think we're safe to proceed. Store the CS buf in
+   * the PIT/CS hashtable entry
+   */
+
+  /*
+   * Start turning the PIT into a CS. Note that we may be stepping on
+   * the PIT part of the union as we update the CS part, so don't
+   * expect the PIT part to be valid after this point.
+   */
+  hicn_buffer_t *hicnb0 = hicn_get_buffer (b0);
+  hicn_pit_to_cs (vm, pitcs, pitp, hash_entry, nodep, dpo_vft, hicn_dpo_id,
+		  hicnb->face_id,
+		  hicnb0->flags & HICN_BUFFER_FLAGS_FACE_IS_APP);
+
+  pitp->shared.create_time = tnow;
+
+  if (dmsg_lifetime < HICN_PARAM_CS_LIFETIME_MIN
+      || dmsg_lifetime > HICN_PARAM_CS_LIFETIME_MAX)
+    {
+      dmsg_lifetime = HICN_PARAM_CS_LIFETIME_DFLT;
+    }
+  pitp->shared.expire_time = hicn_pcs_get_exp_time (tnow, dmsg_lifetime);
+
+  /* Store the original packet buffer in the CS node */
+  pitp->u.cs.cs_pkt_buf = vlib_get_buffer_index (vm, b0);
+}
+
+/* packet trace format function */
+always_inline u8 *
+hicn_data_fwd_format_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 *);
+  hicn_data_fwd_trace_t *t = va_arg (*args, hicn_data_fwd_trace_t *);
+  u32 indent = format_get_indent (s);
+
+  s = format (s, "DATAFWD: pkt: %d, sw_if_index %d, next index %d\n",
+	      (int) t->pkt_type, t->sw_if_index, t->next_index);
+
+  s = format (s, "%U%U", format_white_space, indent,
+	      format_ip6_header, t->packet_data, sizeof (t->packet_data));
+  return (s);
+}
+
+/*
+ * Node registration for the data forwarder node
+ */
+/* *INDENT-OFF* */
+VLIB_REGISTER_NODE(hicn_data_fwd_node) =
+{
+  .function = hicn_data_node_fn,
+  .name = "hicn-data-fwd",
+  .vector_size = sizeof(u32),
+  .format_trace = hicn_data_fwd_format_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .n_errors = ARRAY_LEN(hicn_data_fwd_error_strings),
+  .error_strings = hicn_data_fwd_error_strings,
+  .n_next_nodes = HICN_DATA_FWD_N_NEXT,
+  /* edit / add dispositions here */
+  .next_nodes = {
+    [HICN_DATA_FWD_NEXT_V4_LOOKUP] = "ip4-lookup",
+    [HICN_DATA_FWD_NEXT_V6_LOOKUP] = "ip6-lookup",
+    [HICN_DATA_FWD_NEXT_IFACE4_OUT] = "hicn4-iface-output",
+    [HICN_DATA_FWD_NEXT_IFACE6_OUT] = "hicn6-iface-output",
+    [HICN_DATA_FWD_NEXT_ERROR_DROP] = "error-drop",
+  },
+};
+/* *INDENT-ON* */
+
+/*
+ * fd.io coding-style-patch-verification: ON
+ *
+ * Local Variables: eval: (c-set-style "gnu") End:
+ */