refactor(lib, hicn-light, vpp, hiperf): HICN-723

 - move infra data structure into the shared lib
 - new packet cache using double hashing and lookup on prefix suffix
 - testing updates
 - authenticated requests using interest manifests

Co-authored-by: Mauro Sardara <msardara@cisco.com>
Co-authored-by: Jordan Augé <jordan.auge+fdio@cisco.com>
Co-authored-by: Michele Papalini <micpapal@cisco.com>
Co-authored-by: Olivier Roques <oroques+fdio@cisco.com>
Co-authored-by: Enrico Loparco <eloparco@cisco.com>

Change-Id: Iaddebfe6aa5279ea8553433b0f519578f6b9ccd9
Signed-off-by: Luca Muscariello <muscariello@ieee.org>

1 files changed, 1132 insertions, 0 deletions

diff --git a/hicn-plugin/src/pg_node.c b/hicn-plugin/src/pg_node.c
new file mode 100644
index 000000000..3672a6b72
--- /dev/null
+++ b/hicn-plugin/src/pg_node.c
@@ -0,0 +1,1132 @@
+/*
+ * Copyright (c) 2021 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 <vnet/pg/pg.h>
+#include <vnet/ip/ip.h>
+#include <vnet/ethernet/ethernet.h>
+
+#include "hicn.h"
+#include "pg.h"
+#include "parser.h"
+#include "infra.h"
+
+/* Registration struct for a graph node */
+vlib_node_registration_t hicn_pg_interest_node;
+vlib_node_registration_t hicn_pg_data_node;
+
+/* Stats, which end up called "error" even though they aren't... */
+#define foreach_hicnpg_error                                                  \
+  _ (PROCESSED, "hICN PG packets processed")                                  \
+  _ (DROPPED, "hICN PG packets dropped")                                      \
+  _ (INTEREST_MSGS_GENERATED, "hICN PG Interests generated")                  \
+  _ (CONTENT_MSGS_RECEIVED, "hICN PG Content msgs received")
+
+typedef enum
+{
+#define _(sym, str) HICNPG_ERROR_##sym,
+  foreach_hicnpg_error
+#undef _
+    HICNPG_N_ERROR,
+} hicnpg_error_t;
+
+static char *hicnpg_error_strings[] = {
+#define _(sym, string) string,
+  foreach_hicnpg_error
+#undef _
+};
+
+/*
+ * Next graph nodes, which reference the list in the actual registration
+ * block below
+ */
+typedef enum
+{
+  HICNPG_INTEREST_NEXT_V4_LOOKUP,
+  HICNPG_INTEREST_NEXT_V6_LOOKUP,
+  HICNPG_INTEREST_NEXT_DROP,
+  HICNPG_N_NEXT,
+} hicnpg_interest_next_t;
+
+/* Trace context struct */
+typedef struct
+{
+  u32 next_index;
+  u32 sw_if_index;
+  u8 pkt_type;
+  u16 msg_type;
+} hicnpg_trace_t;
+
+/* packet trace format function */
+static u8 *
+format_hicnpg_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 *);
+  hicnpg_trace_t *t = va_arg (*args, hicnpg_trace_t *);
+
+  s = format (s, "HICNPG: pkt: %d, msg %d, sw_if_index %d, next index %d",
+	      (int) t->pkt_type, (int) t->msg_type, t->sw_if_index,
+	      t->next_index);
+  return (s);
+}
+
+always_inline void hicn_rewrite_interestv4 (vlib_main_t *vm, vlib_buffer_t *b0,
+					    u32 seq_number, u16 lifetime,
+					    u32 next_flow, u32 iface);
+
+always_inline void hicn_rewrite_interestv6 (vlib_main_t *vm, vlib_buffer_t *b0,
+					    u32 seq_number, u16 lifetime,
+					    u32 next_flow, u32 iface);
+
+always_inline void convert_interest_to_data_v4 (vlib_main_t *vm,
+						vlib_buffer_t *b0,
+						vlib_buffer_t *rb, u32 bi0);
+
+always_inline void convert_interest_to_data_v6 (vlib_main_t *vm,
+						vlib_buffer_t *b0,
+						vlib_buffer_t *rb, u32 bi0);
+
+always_inline void calculate_tcp_checksum_v4 (vlib_main_t *vm,
+					      vlib_buffer_t *b0);
+
+always_inline void calculate_tcp_checksum_v6 (vlib_main_t *vm,
+					      vlib_buffer_t *b0);
+/*
+ * Node function for the icn packet-generator client. The goal here is to
+ * manipulate/tweak a stream of packets that have been injected by the vpp
+ * packet generator to generate icn request traffic.
+ */
+static uword
+hicnpg_client_interest_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+				vlib_frame_t *frame)
+{
+  u32 n_left_from, *from, *to_next;
+  hicnpg_interest_next_t next_index;
+  u32 pkts_processed = 0, pkts_dropped = 0;
+  u32 interest_msgs_generated = 0;
+  u32 bi0, bi1;
+  vlib_buffer_t *b0, *b1;
+  u8 pkt_type0 = 0, pkt_type1 = 0;
+  u16 msg_type0 = 0, msg_type1 = 0;
+  hicnpg_main_t *hpgm = &hicnpg_main;
+  int iface = 0;
+
+  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);
+
+      while (n_left_from >= 4 && n_left_to_next >= 2)
+	{
+	  u32 next0 = HICNPG_INTEREST_NEXT_DROP;
+	  u32 next1 = HICNPG_INTEREST_NEXT_DROP;
+	  u32 sw_if_index0 = ~0, sw_if_index1 = ~0;
+	  u8 isv6_0;
+	  u8 isv6_1;
+
+	  /* Prefetch next iteration. */
+	  {
+	    vlib_buffer_t *p2, *p3;
+
+	    p2 = vlib_get_buffer (vm, from[2]);
+	    p3 = vlib_get_buffer (vm, from[3]);
+
+	    vlib_prefetch_buffer_header (p2, LOAD);
+	    vlib_prefetch_buffer_header (p3, LOAD);
+
+	    CLIB_PREFETCH (p2->data, (2 * CLIB_CACHE_LINE_BYTES), STORE);
+	    CLIB_PREFETCH (p3->data, (2 * CLIB_CACHE_LINE_BYTES), STORE);
+	  }
+
+	  /*
+	   * speculatively enqueue b0 and b1 to the current
+	   * next frame
+	   */
+	  to_next[0] = bi0 = from[0];
+	  to_next[1] = bi1 = from[1];
+	  from += 2;
+	  to_next += 2;
+	  n_left_from -= 2;
+	  n_left_to_next -= 2;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+	  b1 = vlib_get_buffer (vm, bi1);
+
+	  hicn_buffer_set_flags (b0, HICN_BUFFER_FLAGS_FROM_PG);
+	  hicn_buffer_set_flags (b1, HICN_BUFFER_FLAGS_FROM_PG);
+
+	  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+	  sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
+	  vnet_buffer (b0)->sw_if_index[VLIB_RX] = hpgm->sw_if;
+	  vnet_buffer (b1)->sw_if_index[VLIB_RX] = hpgm->sw_if;
+
+	  /* Check icn packets, locate names */
+	  if (hicn_interest_parse_pkt (b0) == HICN_ERROR_NONE)
+	    {
+	      /* this node grabs only interests */
+	      isv6_0 = hicn_buffer_is_v6 (b0);
+
+	      /* Increment the appropriate message counter */
+	      interest_msgs_generated++;
+
+	      iface = (hpgm->index_ifaces % hpgm->n_ifaces);
+	      /* Rewrite and send */
+	      isv6_0 ?
+		      hicn_rewrite_interestv6 (
+		  vm, b0, (hpgm->index / hpgm->n_flows) % hpgm->max_seq_number,
+		  hpgm->interest_lifetime, hpgm->index % hpgm->n_flows,
+		  iface) :
+		      hicn_rewrite_interestv4 (
+		  vm, b0, (hpgm->index / hpgm->n_flows) % hpgm->max_seq_number,
+		  hpgm->interest_lifetime, hpgm->index % hpgm->n_flows, iface);
+
+	      hpgm->index_ifaces++;
+	      if (iface == (hpgm->n_ifaces - 1))
+		hpgm->index++;
+
+	      next0 = isv6_0 ? HICNPG_INTEREST_NEXT_V6_LOOKUP :
+				     HICNPG_INTEREST_NEXT_V4_LOOKUP;
+	    }
+	  if (hicn_interest_parse_pkt (b1) == HICN_ERROR_NONE)
+	    {
+	      /* this node grabs only interests */
+	      isv6_1 = hicn_buffer_is_v6 (b1);
+
+	      /* Increment the appropriate message counter */
+	      interest_msgs_generated++;
+
+	      iface = (hpgm->index_ifaces % hpgm->n_ifaces);
+	      /* Rewrite and send */
+	      isv6_1 ?
+		      hicn_rewrite_interestv6 (
+		  vm, b1, (hpgm->index / hpgm->n_flows) % hpgm->max_seq_number,
+		  hpgm->interest_lifetime, hpgm->index % hpgm->n_flows,
+		  iface) :
+		      hicn_rewrite_interestv4 (
+		  vm, b1, (hpgm->index / hpgm->n_flows) % hpgm->max_seq_number,
+		  hpgm->interest_lifetime, hpgm->index % hpgm->n_flows, iface);
+
+	      hpgm->index_ifaces++;
+	      if (iface == (hpgm->n_ifaces - 1))
+		hpgm->index++;
+
+	      next1 = isv6_1 ? HICNPG_INTEREST_NEXT_V6_LOOKUP :
+				     HICNPG_INTEREST_NEXT_V4_LOOKUP;
+	    }
+	  /* Send pkt to next node */
+	  vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
+	  vnet_buffer (b1)->sw_if_index[VLIB_TX] = ~0;
+
+	  pkts_processed += 2;
+
+	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
+	    {
+	      if (b0->flags & VLIB_BUFFER_IS_TRACED)
+		{
+		  hicnpg_trace_t *t =
+		    vlib_add_trace (vm, node, b0, sizeof (*t));
+		  t->pkt_type = pkt_type0;
+		  t->msg_type = msg_type0;
+		  t->sw_if_index = sw_if_index0;
+		  t->next_index = next0;
+		}
+	      if (b1->flags & VLIB_BUFFER_IS_TRACED)
+		{
+		  hicnpg_trace_t *t =
+		    vlib_add_trace (vm, node, b1, sizeof (*t));
+		  t->pkt_type = pkt_type1;
+		  t->msg_type = msg_type1;
+		  t->sw_if_index = sw_if_index1;
+		  t->next_index = next1;
+		}
+	    }
+	  if (next0 == HICNPG_INTEREST_NEXT_DROP)
+	    {
+	      pkts_dropped++;
+	    }
+	  if (next1 == HICNPG_INTEREST_NEXT_DROP)
+	    {
+	      pkts_dropped++;
+	    }
+	  /*
+	   * verify speculative enqueues, maybe switch current
+	   * next frame
+	   */
+	  vlib_validate_buffer_enqueue_x2 (vm, node, next_index, to_next,
+					   n_left_to_next, bi0, bi1, next0,
+					   next1);
+	}
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  u32 next0 = HICNPG_INTEREST_NEXT_DROP;
+	  u32 sw_if_index0;
+	  u8 isv6_0;
+
+	  /* speculatively enqueue b0 to the current next frame */
+	  bi0 = from[0];
+	  to_next[0] = bi0;
+	  from += 1;
+	  to_next += 1;
+	  n_left_from -= 1;
+	  n_left_to_next -= 1;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+
+	  hicn_buffer_set_flags (b0, HICN_BUFFER_FLAGS_FROM_PG);
+
+	  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+	  vnet_buffer (b0)->sw_if_index[VLIB_RX] = hpgm->sw_if;
+
+	  /* Check icn packets, locate names */
+	  if (hicn_interest_parse_pkt (b0) == HICN_ERROR_NONE)
+	    {
+	      /* this node grabs only interests */
+	      isv6_0 = hicn_buffer_is_v6 (b0);
+
+	      /* Increment the appropriate message counter */
+	      interest_msgs_generated++;
+
+	      iface = (hpgm->index_ifaces % hpgm->n_ifaces);
+
+	      /* Rewrite and send */
+	      isv6_0 ?
+		      hicn_rewrite_interestv6 (
+		  vm, b0, (hpgm->index / hpgm->n_flows) % hpgm->max_seq_number,
+		  hpgm->interest_lifetime, hpgm->index % hpgm->n_flows,
+		  iface) :
+		      hicn_rewrite_interestv4 (
+		  vm, b0, (hpgm->index / hpgm->n_flows) % hpgm->max_seq_number,
+		  hpgm->interest_lifetime, hpgm->index % hpgm->n_flows, iface);
+
+	      hpgm->index_ifaces++;
+	      if (iface == (hpgm->n_ifaces - 1))
+		hpgm->index++;
+
+	      next0 = isv6_0 ? HICNPG_INTEREST_NEXT_V6_LOOKUP :
+				     HICNPG_INTEREST_NEXT_V4_LOOKUP;
+	    }
+	  /* Send pkt to ip lookup */
+	  vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
+
+	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) &&
+			     (b0->flags & VLIB_BUFFER_IS_TRACED)))
+	    {
+	      hicnpg_trace_t *t = vlib_add_trace (vm, node, b0, sizeof (*t));
+	      t->pkt_type = pkt_type0;
+	      t->msg_type = msg_type0;
+	      t->sw_if_index = sw_if_index0;
+	      t->next_index = next0;
+	    }
+	  pkts_processed += 1;
+
+	  if (next0 == HICNPG_INTEREST_NEXT_DROP)
+	    {
+	      pkts_dropped++;
+	    }
+	  /*
+	   * verify speculative enqueue, maybe switch current
+	   * next frame
+	   */
+	  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);
+    }
+
+  vlib_node_increment_counter (vm, hicn_pg_interest_node.index,
+			       HICNPG_ERROR_PROCESSED, pkts_processed);
+  vlib_node_increment_counter (vm, hicn_pg_interest_node.index,
+			       HICNPG_ERROR_DROPPED, pkts_dropped);
+  vlib_node_increment_counter (vm, hicn_pg_interest_node.index,
+			       HICNPG_ERROR_INTEREST_MSGS_GENERATED,
+			       interest_msgs_generated);
+
+  return (frame->n_vectors);
+}
+
+void
+hicn_rewrite_interestv4 (vlib_main_t *vm, vlib_buffer_t *b0, u32 seq_number,
+			 u16 interest_lifetime, u32 next_flow, u32 iface)
+{
+  hicn_header_t *h0 = vlib_buffer_get_current (b0);
+
+  /* Generate the right src and dst corresponding to flow and iface */
+  ip46_address_t src_addr = {
+    .ip4 = hicnpg_main.pgen_clt_src_addr.ip4,
+  };
+  hicn_name_t dst_name = {
+    .prefix.ip4 = hicnpg_main.pgen_clt_hicn_name->fp_addr.ip4,
+    .suffix = seq_number,
+  };
+
+  src_addr.ip4.as_u32 += clib_host_to_net_u32 (iface);
+  dst_name.prefix.ip4.as_u32 += clib_net_to_host_u32 (next_flow);
+
+  /* Update locator and name */
+  hicn_type_t type = hicn_get_buffer (b0)->type;
+  HICN_OPS4->set_interest_locator (type, &h0->protocol, &src_addr);
+  HICN_OPS4->set_interest_name (type, &h0->protocol, &dst_name);
+
+  /* Update lifetime  (currently L4 checksum is not updated) */
+  HICN_OPS4->set_lifetime (type, &h0->protocol, interest_lifetime);
+
+  /* Update checksums */
+  HICN_OPS4->update_checksums (type, &h0->protocol, 0, 0);
+}
+
+/**
+ * @brief Rewrite the IPv6 header as the next generated packet
+ *
+ * Set up a name prefix
+ *  - etiher generate interest in which the name varies only after the prefix
+ *  (inc : seq_number), then the flow acts on the prefix (CHECK)
+ *  seq_number => TCP, FLOW =>
+ *
+ *  SRC : pgen_clt_src_addr.ip6 DST = generate name (pgen_clt_hicn_name.ip6)
+ *  ffff:ffff:ffff:ffff         ffff:ffff:ffff:ffff
+ *                 \__/                        \__/
+ *                 +iface                      + flow
+ *  Source is used to emulate different consumers.
+ *    FIXME iface is ill-named, better name it consumer id
+ *  Destination is used to iterate on the content.
+ */
+void
+hicn_rewrite_interestv6 (vlib_main_t *vm, vlib_buffer_t *b0, u32 seq_number,
+			 u16 interest_lifetime, u32 next_flow, u32 iface)
+{
+  hicn_header_t *h0 = vlib_buffer_get_current (b0);
+
+  /* Generate the right src and dst corresponding to flow and iface */
+  ip46_address_t src_addr = {
+    .ip6 = hicnpg_main.pgen_clt_src_addr.ip6,
+  };
+  hicn_name_t dst_name = {
+    .prefix.ip6 = hicnpg_main.pgen_clt_hicn_name->fp_addr.ip6,
+    .suffix = seq_number,
+  };
+  src_addr.ip6.as_u32[3] += clib_host_to_net_u32 (iface);
+  dst_name.prefix.ip6.as_u32[3] += clib_net_to_host_u32 (next_flow);
+
+  /* Update locator and name */
+  hicn_type_t type = hicn_get_buffer (b0)->type;
+  HICN_OPS6->set_interest_locator (type, &h0->protocol, &src_addr);
+  HICN_OPS6->set_interest_name (type, &h0->protocol, &dst_name);
+
+  /* Update lifetime */
+  HICN_OPS6->set_lifetime (type, &h0->protocol, interest_lifetime);
+
+  /* Update checksums */
+  calculate_tcp_checksum_v6 (vm, b0);
+}
+
+void
+calculate_tcp_checksum_v4 (vlib_main_t *vm, vlib_buffer_t *b0)
+{
+  ip4_header_t *ip0;
+  tcp_header_t *tcp0;
+  ip_csum_t sum0;
+  u32 tcp_len0;
+
+  ip0 = (ip4_header_t *) (vlib_buffer_get_current (b0));
+  tcp0 =
+    (tcp_header_t *) (vlib_buffer_get_current (b0) + sizeof (ip4_header_t));
+  tcp_len0 = clib_net_to_host_u16 (ip0->length) - sizeof (ip4_header_t);
+
+  /* Initialize checksum with header. */
+  if (BITS (sum0) == 32)
+    {
+      sum0 = clib_mem_unaligned (&ip0->src_address, u32);
+      sum0 =
+	ip_csum_with_carry (sum0, clib_mem_unaligned (&ip0->dst_address, u32));
+    }
+  else
+    sum0 = clib_mem_unaligned (&ip0->src_address, u64);
+
+  sum0 = ip_csum_with_carry (
+    sum0, clib_host_to_net_u32 (tcp_len0 + (ip0->protocol << 16)));
+
+  /* Invalidate possibly old checksum. */
+  tcp0->checksum = 0;
+
+  u32 tcp_offset = sizeof (ip4_header_t);
+  sum0 = ip_incremental_checksum_buffer (vm, b0, tcp_offset, tcp_len0, sum0);
+
+  tcp0->checksum = ~ip_csum_fold (sum0);
+}
+
+void
+calculate_tcp_checksum_v6 (vlib_main_t *vm, vlib_buffer_t *b0)
+{
+  ip6_header_t *ip0;
+  tcp_header_t *tcp0;
+  ip_csum_t sum0;
+  u32 tcp_len0;
+
+  ip0 = (ip6_header_t *) (vlib_buffer_get_current (b0));
+  tcp0 =
+    (tcp_header_t *) (vlib_buffer_get_current (b0) + sizeof (ip6_header_t));
+  tcp_len0 = clib_net_to_host_u16 (ip0->payload_length);
+
+  /* Initialize checksum with header. */
+  if (BITS (sum0) == 32)
+    {
+      sum0 = clib_mem_unaligned (&ip0->src_address, u32);
+      sum0 =
+	ip_csum_with_carry (sum0, clib_mem_unaligned (&ip0->dst_address, u32));
+    }
+  else
+    sum0 = clib_mem_unaligned (&ip0->src_address, u64);
+
+  sum0 = ip_csum_with_carry (
+    sum0, clib_host_to_net_u32 (tcp_len0 + (ip0->protocol << 16)));
+
+  /* Invalidate possibly old checksum. */
+  tcp0->checksum = 0;
+
+  u32 tcp_offset = sizeof (ip6_header_t);
+  sum0 = ip_incremental_checksum_buffer (vm, b0, tcp_offset, tcp_len0, sum0);
+
+  tcp0->checksum = ~ip_csum_fold (sum0);
+}
+
+VLIB_REGISTER_NODE (hicn_pg_interest_node) = {
+  .function = hicnpg_client_interest_node_fn,
+  .name = "hicnpg-interest",
+  .vector_size = sizeof (u32),
+  .format_trace = format_hicnpg_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .n_errors = ARRAY_LEN (hicnpg_error_strings),
+  .error_strings = hicnpg_error_strings,
+  .n_next_nodes = HICNPG_N_NEXT,
+  .next_nodes = { [HICNPG_INTEREST_NEXT_V4_LOOKUP] = "ip4-lookup",
+		  [HICNPG_INTEREST_NEXT_V6_LOOKUP] = "ip6-lookup",
+		  [HICNPG_INTEREST_NEXT_DROP] = "error-drop" },
+};
+
+/*
+ * Next graph nodes, which reference the list in the actual registration
+ * block below
+ */
+typedef enum
+{
+  HICNPG_DATA_NEXT_DROP,
+  HICNPG_DATA_NEXT_LOOKUP4,
+  HICNPG_DATA_NEXT_LOOKUP6,
+  HICNPG_DATA_N_NEXT,
+} hicnpg_data_next_t;
+
+/* Trace context struct */
+typedef struct
+{
+  u32 next_index;
+  u32 sw_if_index;
+  u8 pkt_type;
+  u16 msg_type;
+} icnpg_data_trace_t;
+
+/* packet trace format function */
+static u8 *
+format_hicnpg_data_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 *);
+  hicnpg_trace_t *t = va_arg (*args, hicnpg_trace_t *);
+
+  s = format (s, "HICNPG: pkt: %d, msg %d, sw_if_index %d, next index %d",
+	      (int) t->pkt_type, (int) t->msg_type, t->sw_if_index,
+	      t->next_index);
+  return (s);
+}
+
+/*
+ * Node function for the icn packet-generator client. The goal here is to
+ * manipulate/tweak a stream of packets that have been injected by the vpp
+ * packet generator to generate icn request traffic.
+ */
+static uword
+hicnpg_client_data_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+			    vlib_frame_t *frame)
+{
+  u32 n_left_from, *from, *to_next;
+  hicnpg_data_next_t next_index;
+  u32 pkts_processed = 0;
+  u32 content_msgs_received = 0;
+  u32 bi0, bi1;
+  vlib_buffer_t *b0, *b1;
+  u8 pkt_type0 = 0, pkt_type1 = 0;
+  u16 msg_type0 = 1, msg_type1 = 1;
+
+  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);
+
+      while (n_left_from >= 4 && n_left_to_next >= 2)
+	{
+	  u32 next0 = HICNPG_DATA_NEXT_DROP;
+	  u32 next1 = HICNPG_DATA_NEXT_DROP;
+	  u32 sw_if_index0, sw_if_index1;
+
+	  /* Prefetch next iteration. */
+	  {
+	    vlib_buffer_t *p2, *p3;
+
+	    p2 = vlib_get_buffer (vm, from[2]);
+	    p3 = vlib_get_buffer (vm, from[3]);
+
+	    vlib_prefetch_buffer_header (p2, LOAD);
+	    vlib_prefetch_buffer_header (p3, LOAD);
+
+	    CLIB_PREFETCH (p2->data, (2 * CLIB_CACHE_LINE_BYTES), STORE);
+	    CLIB_PREFETCH (p3->data, (2 * CLIB_CACHE_LINE_BYTES), STORE);
+	  }
+
+	  /*
+	   * speculatively enqueue b0 and b1 to the current
+	   * next frame
+	   */
+	  to_next[0] = bi0 = from[0];
+	  to_next[1] = bi1 = from[1];
+	  from += 2;
+	  to_next += 2;
+	  n_left_from -= 2;
+	  n_left_to_next -= 2;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+	  b1 = vlib_get_buffer (vm, bi1);
+
+	  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+	  sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
+
+	  next0 = HICNPG_DATA_NEXT_DROP;
+	  next1 = HICNPG_DATA_NEXT_DROP;
+
+	  // Increment counter
+	  content_msgs_received += 2;
+
+	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
+	    {
+	      if (b0->flags & VLIB_BUFFER_IS_TRACED)
+		{
+		  icnpg_data_trace_t *t =
+		    vlib_add_trace (vm, node, b0, sizeof (*t));
+		  t->pkt_type = pkt_type0;
+		  t->msg_type = msg_type0;
+		  t->sw_if_index = sw_if_index0;
+		  t->next_index = next0;
+		}
+	      if (b1->flags & VLIB_BUFFER_IS_TRACED)
+		{
+		  icnpg_data_trace_t *t =
+		    vlib_add_trace (vm, node, b1, sizeof (*t));
+		  t->pkt_type = pkt_type1;
+		  t->msg_type = msg_type1;
+		  t->sw_if_index = sw_if_index1;
+		  t->next_index = next1;
+		}
+	    }
+
+	  vlib_validate_buffer_enqueue_x2 (vm, node, next_index, to_next,
+					   n_left_to_next, bi0, bi1, next0,
+					   next1);
+	  pkts_processed += 2;
+	}
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  u32 next0 = HICNPG_DATA_NEXT_DROP;
+	  u32 sw_if_index0;
+
+	  /* speculatively enqueue b0 to the current next frame */
+	  bi0 = from[0];
+	  to_next[0] = bi0;
+	  from += 1;
+	  to_next += 1;
+	  n_left_from -= 1;
+	  n_left_to_next -= 1;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+
+	  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+
+	  next0 = HICNPG_DATA_NEXT_DROP;
+
+	  // Increment a counter
+	  content_msgs_received += 1;
+
+	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) &&
+			     (b0->flags & VLIB_BUFFER_IS_TRACED)))
+	    {
+	      icnpg_data_trace_t *t =
+		vlib_add_trace (vm, node, b0, sizeof (*t));
+	      t->pkt_type = pkt_type0;
+	      t->msg_type = msg_type0;
+	      t->sw_if_index = sw_if_index0;
+	      t->next_index = next0;
+	    }
+
+	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
+					   n_left_to_next, bi0, next0);
+
+	  pkts_processed++;
+	}
+      vlib_put_next_frame (vm, node, next_index, n_left_to_next);
+    }
+
+  vlib_node_increment_counter (vm, hicn_pg_data_node.index,
+			       HICNPG_ERROR_PROCESSED, pkts_processed);
+  vlib_node_increment_counter (vm, hicn_pg_data_node.index,
+			       HICNPG_ERROR_CONTENT_MSGS_RECEIVED,
+			       content_msgs_received);
+  return (frame->n_vectors);
+}
+
+VLIB_REGISTER_NODE(hicn_pg_data_node) =
+{
+  .function = hicnpg_client_data_node_fn,
+  .name = "hicnpg-data",
+  .vector_size = sizeof(u32),
+  .format_trace = format_hicnpg_data_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .n_errors = ARRAY_LEN(hicnpg_error_strings),
+  .error_strings = hicnpg_error_strings,
+  .n_next_nodes = HICNPG_DATA_N_NEXT,
+  .next_nodes =
+  {
+   [HICNPG_DATA_NEXT_DROP] = "error-drop",
+   [HICNPG_DATA_NEXT_LOOKUP4] = "ip4-lookup",
+   [HICNPG_DATA_NEXT_LOOKUP6] = "ip6-lookup",
+  },
+};
+
+VNET_FEATURE_INIT (hicn_data_input_ip4_arc, static) = {
+  .arc_name = "ip4-unicast",
+  .node_name = "hicnpg-data",
+  .runs_before = VNET_FEATURES ("ip4-inacl"),
+};
+
+VNET_FEATURE_INIT (hicn_data_input_ip6_arc, static) = {
+  .arc_name = "ip6-unicast",
+  .node_name = "hicnpg-data",
+  .runs_before = VNET_FEATURES ("ip6-inacl"),
+};
+
+/*
+ * End of packet-generator client node
+ */
+
+/*
+ * Beginning of packet-generation server node
+ */
+
+/* Registration struct for a graph node */
+vlib_node_registration_t hicn_pg_server_node;
+
+/* Stats, which end up called "error" even though they aren't... */
+#define foreach_icnpg_server_error                                            \
+  _ (PROCESSED, "hICN PG Server packets processed")                           \
+  _ (DROPPED, "hICN PG Server packets dropped")
+
+typedef enum
+{
+#define _(sym, str) HICNPG_SERVER_ERROR_##sym,
+  foreach_icnpg_server_error
+#undef _
+    HICNPG_SERVER_N_ERROR,
+} icnpg_server_error_t;
+
+static char *icnpg_server_error_strings[] = {
+#define _(sym, string) string,
+  foreach_icnpg_server_error
+#undef _
+};
+
+/*
+ * Next graph nodes, which reference the list in the actual registration
+ * block below
+ */
+typedef enum
+{
+  HICNPG_SERVER_NEXT_V4_LOOKUP,
+  HICNPG_SERVER_NEXT_V6_LOOKUP,
+  HICNPG_SERVER_NEXT_DROP,
+  HICNPG_SERVER_N_NEXT,
+} icnpg_server_next_t;
+
+/* Trace context struct */
+typedef struct
+{
+  u32 next_index;
+  u32 sw_if_index;
+  u8 pkt_type;
+  u16 msg_type;
+} hicnpg_server_trace_t;
+
+/* packet trace format function */
+static u8 *
+format_icnpg_server_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 *);
+  hicnpg_server_trace_t *t = va_arg (*args, hicnpg_server_trace_t *);
+
+  s = format (
+    s, "HICNPG SERVER: pkt: %d, msg %d, sw_if_index %d, next index %d",
+    (int) t->pkt_type, (int) t->msg_type, t->sw_if_index, t->next_index);
+  return (s);
+}
+
+/*
+ * Node function for the icn packet-generator server.
+ */
+static uword
+hicnpg_node_server_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
+		       vlib_frame_t *frame, int isv6)
+{
+  u32 n_left_from, *from, *to_next;
+  icnpg_server_next_t next_index;
+  u32 pkts_processed = 0, pkts_dropped = 0;
+  u32 bi0, bi1;
+  vlib_buffer_t *b0, *b1;
+  u8 pkt_type0 = 0, pkt_type1 = 0;
+  u16 msg_type0 = 0, msg_type1 = 0;
+
+  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);
+
+      while (n_left_from >= 4 && n_left_to_next >= 2)
+	{
+	  u32 next0 = HICNPG_SERVER_NEXT_DROP;
+	  u32 next1 = HICNPG_SERVER_NEXT_DROP;
+	  u32 sw_if_index0, sw_if_index1;
+	  u32 hpgi0, hpgi1;
+	  hicnpg_server_t *hpg0, *hpg1;
+
+	  /* Prefetch next iteration. */
+	  {
+	    vlib_buffer_t *p2, *p3;
+
+	    p2 = vlib_get_buffer (vm, from[2]);
+	    p3 = vlib_get_buffer (vm, from[3]);
+
+	    vlib_prefetch_buffer_header (p2, LOAD);
+	    vlib_prefetch_buffer_header (p3, LOAD);
+
+	    CLIB_PREFETCH (p2->data, (2 * CLIB_CACHE_LINE_BYTES), STORE);
+	    CLIB_PREFETCH (p3->data, (2 * CLIB_CACHE_LINE_BYTES), STORE);
+	  }
+
+	  /*
+	   * speculatively enqueue b0 and b1 to the current
+	   * next frame
+	   */
+	  to_next[0] = bi0 = from[0];
+	  to_next[1] = bi1 = from[1];
+	  from += 2;
+	  to_next += 2;
+	  n_left_from -= 2;
+	  n_left_to_next -= 2;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+	  b1 = vlib_get_buffer (vm, bi1);
+
+	  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+	  sw_if_index1 = vnet_buffer (b1)->sw_if_index[VLIB_RX];
+
+	  vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
+	  vnet_buffer (b1)->sw_if_index[VLIB_TX] = ~0;
+
+	  hpgi0 = vnet_buffer (b0)->ip.adj_index[VLIB_TX];
+	  hpgi1 = vnet_buffer (b1)->ip.adj_index[VLIB_TX];
+
+	  hpg0 = hicnpg_server_get (hpgi0);
+	  hpg1 = hicnpg_server_get (hpgi1);
+
+	  if (hicn_interest_parse_pkt (b0) == HICN_ERROR_NONE)
+	    {
+	      vlib_buffer_t *rb = NULL;
+	      rb = vlib_get_buffer (vm, hpg0->buffer_index);
+
+	      isv6 ? convert_interest_to_data_v6 (vm, b0, rb, bi0) :
+			   convert_interest_to_data_v4 (vm, b0, rb, bi0);
+
+	      next0 = isv6 ? HICNPG_SERVER_NEXT_V6_LOOKUP :
+				   HICNPG_SERVER_NEXT_V4_LOOKUP;
+	    }
+
+	  if (hicn_interest_parse_pkt (b1) == HICN_ERROR_NONE)
+	    {
+	      vlib_buffer_t *rb = NULL;
+	      rb = vlib_get_buffer (vm, hpg1->buffer_index);
+
+	      isv6 ? convert_interest_to_data_v6 (vm, b1, rb, bi1) :
+			   convert_interest_to_data_v4 (vm, b1, rb, bi1);
+
+	      next1 = isv6 ? HICNPG_SERVER_NEXT_V6_LOOKUP :
+				   HICNPG_SERVER_NEXT_V4_LOOKUP;
+	    }
+	  pkts_processed += 2;
+
+	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE)))
+	    {
+	      if (b0->flags & VLIB_BUFFER_IS_TRACED)
+		{
+		  hicnpg_server_trace_t *t =
+		    vlib_add_trace (vm, node, b0, sizeof (*t));
+		  t->pkt_type = pkt_type0;
+		  t->msg_type = msg_type0;
+		  t->sw_if_index = sw_if_index0;
+		  t->next_index = next0;
+		}
+	      if (b1->flags & VLIB_BUFFER_IS_TRACED)
+		{
+		  hicnpg_server_trace_t *t =
+		    vlib_add_trace (vm, node, b1, sizeof (*t));
+		  t->pkt_type = pkt_type1;
+		  t->msg_type = msg_type1;
+		  t->sw_if_index = sw_if_index1;
+		  t->next_index = next1;
+		}
+	    }
+	  if (next0 == HICNPG_SERVER_NEXT_DROP)
+	    {
+	      pkts_dropped++;
+	    }
+	  if (next1 == HICNPG_SERVER_NEXT_DROP)
+	    {
+	      pkts_dropped++;
+	    }
+	  /*
+	   * verify speculative enqueues, maybe switch current
+	   * next frame
+	   */
+	  vlib_validate_buffer_enqueue_x2 (vm, node, next_index, to_next,
+					   n_left_to_next, bi0, bi1, next0,
+					   next1);
+	}
+
+      while (n_left_from > 0 && n_left_to_next > 0)
+	{
+	  u32 next0 = HICNPG_SERVER_NEXT_DROP;
+	  u32 sw_if_index0 = ~0;
+	  u32 hpgi0;
+	  hicnpg_server_t *hpg0;
+
+	  /* speculatively enqueue b0 to the current next frame */
+	  bi0 = from[0];
+	  to_next[0] = bi0;
+	  from += 1;
+	  to_next += 1;
+	  n_left_from -= 1;
+	  n_left_to_next -= 1;
+
+	  b0 = vlib_get_buffer (vm, bi0);
+
+	  sw_if_index0 = vnet_buffer (b0)->sw_if_index[VLIB_RX];
+	  vnet_buffer (b0)->sw_if_index[VLIB_TX] = ~0;
+
+	  hpgi0 = vnet_buffer (b0)->ip.adj_index[VLIB_TX];
+	  hpg0 = hicnpg_server_get (hpgi0);
+
+	  if (hicn_interest_parse_pkt (b0) == HICN_ERROR_NONE)
+	    {
+	      /* this node grabs only interests */
+	      vlib_buffer_t *rb = NULL;
+	      rb = vlib_get_buffer (vm, hpg0->buffer_index);
+
+	      isv6 ? convert_interest_to_data_v6 (vm, b0, rb, bi0) :
+			   convert_interest_to_data_v4 (vm, b0, rb, bi0);
+
+	      next0 = isv6 ? HICNPG_SERVER_NEXT_V6_LOOKUP :
+				   HICNPG_SERVER_NEXT_V4_LOOKUP;
+	    }
+	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) &&
+			     (b0->flags & VLIB_BUFFER_IS_TRACED)))
+	    {
+	      hicnpg_server_trace_t *t =
+		vlib_add_trace (vm, node, b0, sizeof (*t));
+	      t->pkt_type = pkt_type0;
+	      t->msg_type = msg_type0;
+	      t->sw_if_index = sw_if_index0;
+	      t->next_index = next0;
+	    }
+	  pkts_processed += 1;
+
+	  if (next0 == HICNPG_SERVER_NEXT_DROP)
+	    {
+	      pkts_dropped++;
+	    }
+	  /*
+	   * verify speculative enqueue, maybe switch current
+	   * next frame
+	   */
+	  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);
+    }
+
+  vlib_node_increment_counter (vm, hicn_pg_server_node.index,
+			       HICNPG_SERVER_ERROR_PROCESSED, pkts_processed);
+  vlib_node_increment_counter (vm, hicn_pg_server_node.index,
+			       HICNPG_SERVER_ERROR_DROPPED, pkts_dropped);
+
+  return (frame->n_vectors);
+}
+
+void
+convert_interest_to_data_v4 (vlib_main_t *vm, vlib_buffer_t *b0,
+			     vlib_buffer_t *rb, u32 bi0)
+{
+  hicn_header_t *h0 = vlib_buffer_get_current (b0);
+
+  /* Get the packet length */
+  u16 pkt_len = clib_net_to_host_u16 (h0->v4.ip.len);
+
+  /*
+   * Rule of thumb: We want the size of the IP packet to be <= 1500 bytes
+   */
+  u16 bytes_to_copy = rb->current_length;
+  if ((bytes_to_copy + pkt_len) > 1500)
+    {
+      bytes_to_copy = 1500 - pkt_len;
+    }
+  /* Add content to the data packet */
+  vlib_buffer_add_data (vm, &bi0, rb->data, bytes_to_copy);
+
+  b0 = vlib_get_buffer (vm, bi0);
+
+  h0 = vlib_buffer_get_current (b0);
+
+  ip4_address_t src_addr = h0->v4.ip.saddr;
+  h0->v4.ip.saddr = h0->v4.ip.daddr;
+  h0->v4.ip.daddr = src_addr;
+
+  h0->v4.ip.len = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0));
+  h0->v4.ip.csum = ip4_header_checksum ((ip4_header_t *) &(h0->v4.ip));
+  calculate_tcp_checksum_v4 (vm, b0);
+}
+
+void
+convert_interest_to_data_v6 (vlib_main_t *vm, vlib_buffer_t *b0,
+			     vlib_buffer_t *rb, u32 bi0)
+{
+  hicn_header_t *h0 = vlib_buffer_get_current (b0);
+
+  /* Get the packet length */
+  uint16_t pkt_len =
+    clib_net_to_host_u16 (h0->v6.ip.len) + sizeof (ip6_header_t);
+
+  /*
+   * Figure out how many bytes we can add to the content
+   *
+   * Rule of thumb: We want the size of the IP packet to be <= 1400 bytes
+   */
+  u16 bytes_to_copy = rb->current_length;
+  if ((bytes_to_copy + pkt_len) > 1500)
+    {
+      bytes_to_copy = 1500 - pkt_len;
+    }
+  /* Add content to the data packet */
+  vlib_buffer_add_data (vm, &bi0, rb->data, bytes_to_copy);
+
+  b0 = vlib_get_buffer (vm, bi0);
+
+  h0 = vlib_buffer_get_current (b0);
+  ip6_address_t src_addr = h0->v6.ip.saddr;
+  h0->v6.ip.saddr = h0->v6.ip.daddr;
+  h0->v6.ip.daddr = src_addr;
+
+  h0->v6.ip.len = clib_host_to_net_u16 (vlib_buffer_length_in_chain (vm, b0) -
+					sizeof (ip6_header_t));
+  h0->v6.tcp.data_offset_and_reserved |= 0x0f;
+  h0->v6.tcp.urg_ptr = htons (0xffff);
+
+  calculate_tcp_checksum_v6 (vm, b0);
+}
+
+VLIB_NODE_FN (hicn_pg_server6_node)
+(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
+{
+  return hicnpg_node_server_fn (vm, node, frame, 1 /* is_v6 */);
+}
+
+VLIB_NODE_FN (hicn_pg_server4_node)
+(vlib_main_t *vm, vlib_node_runtime_t *node, vlib_frame_t *frame)
+{
+  return hicnpg_node_server_fn (vm, node, frame, 0 /* is_v6 */);
+}
+
+VLIB_REGISTER_NODE(hicn_pg_server6_node) =
+{
+  .name = "hicnpg-server-6",
+  .vector_size = sizeof(u32),
+  .format_trace = format_icnpg_server_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .n_errors = ARRAY_LEN(icnpg_server_error_strings),
+  .error_strings = icnpg_server_error_strings,
+  .n_next_nodes = HICNPG_SERVER_N_NEXT,
+  /* edit / add dispositions here */
+  .next_nodes =
+  {
+    [HICNPG_SERVER_NEXT_V4_LOOKUP] = "ip4-lookup",
+    [HICNPG_SERVER_NEXT_V6_LOOKUP] = "ip6-lookup",
+    [HICNPG_SERVER_NEXT_DROP] = "error-drop",
+  },
+};
+
+VLIB_REGISTER_NODE(hicn_pg_server4_node) =
+{
+  .name = "hicnpg-server-4",
+  .vector_size = sizeof(u32),
+  .format_trace = format_icnpg_server_trace,
+  .type = VLIB_NODE_TYPE_INTERNAL,
+  .n_errors = ARRAY_LEN(icnpg_server_error_strings),
+  .error_strings = icnpg_server_error_strings,
+  .n_next_nodes = HICNPG_SERVER_N_NEXT,
+  /* edit / add dispositions here */
+  .next_nodes =
+  {
+    [HICNPG_SERVER_NEXT_V4_LOOKUP] = "ip4-lookup",
+    [HICNPG_SERVER_NEXT_V6_LOOKUP] = "ip6-lookup",
+    [HICNPG_SERVER_NEXT_DROP] = "error-drop",
+  },
+};
+
+/*
+ * End of packet-generator server node
+ */
\ No newline at end of file