feat(hicn-plugin): handle case of no exact match for mapme IU

Ticket: HICN-844

Change-Id: I1f046e6327e4cf507b7fa7a5adae53e63ab491bf
Signed-off-by: Mauro Sardara <msardara@cisco.com>

1 files changed, 200 insertions, 40 deletions

diff --git a/hicn-plugin/src/mapme_ctrl_node.c b/hicn-plugin/src/mapme_ctrl_node.c
index e3d340e53..5d4fc5c12 100644
--- a/hicn-plugin/src/mapme_ctrl_node.c
+++ b/hicn-plugin/src/mapme_ctrl_node.c
@@ -50,7 +50,7 @@ static char *hicn_mapme_ctrl_error_strings[] = {
 };
 
 static_always_inline int
-hicn_mapme_nh_set (hicn_mapme_tfib_t *tfib, hicn_face_id_t face_id)
+hicn_mapme_nh_set (hicn_mapme_tfib_t *tfib, hicn_face_id_t in_face_id)
 {
   hicn_dpo_ctx_t *strategy_ctx = (hicn_dpo_ctx_t *) tfib;
   const fib_prefix_t *prefix =
@@ -58,11 +58,13 @@ hicn_mapme_nh_set (hicn_mapme_tfib_t *tfib, hicn_face_id_t face_id)
 
   int ret = 0;
 
-  if ((tfib->entry_count == 1) && (tfib->next_hops[0] == face_id))
+  if ((tfib->entry_count == 1) && (tfib->next_hops[0] == in_face_id))
     return ret;
 
+  /*
+   * Remove all the existing next hops and set the new one
+   */
   u32 n_entries = tfib->entry_count;
-  /* Remove all the existing next hops and set the new one */
   for (int i = 0; i < n_entries; i++)
     {
       hicn_face_t *face = hicn_dpoi_get_from_idx (strategy_ctx->next_hops[0]);
@@ -73,8 +75,7 @@ hicn_mapme_nh_set (hicn_mapme_tfib_t *tfib, hicn_face_id_t face_id)
 				    &adj->sub_type.nbr.next_hop, face->sw_if,
 				    0);
 	}
-      else if (face->dpo.dpoi_type == dpo_type_udp_ip4 ||
-	       face->dpo.dpoi_type == dpo_type_udp_ip6)
+      else if (dpo_is_udp_encap (&face->dpo))
 	{
 	  ip_nh_udp_tunnel_add_del_helper (prefix->fp_proto, prefix,
 					   face->dpo.dpoi_index,
@@ -87,9 +88,8 @@ hicn_mapme_nh_set (hicn_mapme_tfib_t *tfib, hicn_face_id_t face_id)
     }
 
   ret = HICN_ERROR_MAPME_NEXT_HOP_ADDED;
-  hicn_face_t *face = hicn_dpoi_get_from_idx (face_id);
-  if (face->dpo.dpoi_type == dpo_type_udp_ip4 ||
-      face->dpo.dpoi_type == dpo_type_udp_ip6)
+  hicn_face_t *face = hicn_dpoi_get_from_idx (in_face_id);
+  if (dpo_is_udp_encap (&face->dpo))
     {
       ip_nh_udp_tunnel_add_del_helper (prefix->fp_proto, prefix,
 				       face->dpo.dpoi_index,
@@ -137,8 +137,8 @@ hicn_mapme_nh_add (hicn_mapme_tfib_t *tfib, hicn_face_id_t face_id)
   const fib_prefix_t *prefix =
     fib_entry_get_prefix (strategy_ctx->fib_entry_index);
   hicn_face_t *face = hicn_dpoi_get_from_idx (face_id);
-  if (face->dpo.dpoi_type == dpo_type_udp_ip4 ||
-      face->dpo.dpoi_type == dpo_type_udp_ip6)
+
+  if (dpo_is_udp_encap (&face->dpo))
     {
       ip_nh_udp_tunnel_add_del_helper ((fib_protocol_t) face->dpo.dpoi_proto,
 				       prefix, face->dpo.dpoi_index,
@@ -153,6 +153,80 @@ hicn_mapme_nh_add (hicn_mapme_tfib_t *tfib, hicn_face_id_t face_id)
   return 0;
 }
 
+/**
+ * @brief Add a route to the fib.
+ *
+ */
+static_always_inline int
+hicn_mapme_add_fib_entry (const fib_prefix_t *prefix,
+			  hicn_face_id_t in_face_id,
+			  fib_node_index_t *hicn_fib_node_index)
+{
+  int ret = HICN_ERROR_NONE;
+  dpo_proto_t dpo_proto = DPO_PROTO_NONE;
+
+  hicn_face_t *face = hicn_dpoi_get_from_idx (in_face_id);
+
+  if (face->sw_if == ~0)
+    {
+      // UDP encap case
+      if (face->flags & HICN_FACE_FLAGS_UDP4)
+	{
+	  dpo_proto = DPO_PROTO_IP4;
+	}
+      else if (face->flags & HICN_FACE_FLAGS_UDP6)
+	{
+	  dpo_proto = DPO_PROTO_IP6;
+	}
+      else
+	{
+	  // Invalid
+	  return HICN_ERROR_FACE_NOT_VALID;
+	}
+
+      ret = ip_nh_udp_tunnel_add_del_helper (
+	prefix->fp_proto, prefix, face->dpo.dpoi_index, dpo_proto, 1);
+    }
+  else
+    {
+      ret = ip_nh_adj_add_del_helper (prefix->fp_proto, prefix,
+				      &face->nat_addr, face->sw_if, 1);
+    }
+
+  if (ret != HICN_ERROR_NONE)
+    {
+      return ret;
+    }
+
+  // Now let's trigger the sync the main table with the hicn table
+  hicn_face_id_t *vec_faces = NULL;
+  ret = hicn_route_enable (prefix, hicn_fib_node_index, &vec_faces);
+
+  if (vec_faces[0] != in_face_id)
+    {
+      HICN_ERROR ("Created new face: new face id: %d, in_face id: %d",
+		  vec_faces[0], in_face_id);
+      ret = HICN_ERROR_MAPME_WRONG_FACE_CREATED;
+    }
+
+  return ret;
+}
+
+/**
+ * Convert hicn prefix to fib prefix
+ */
+static_always_inline void
+hicn_prefix_to_fib_prefix (const hicn_prefix_t *prefix_in,
+			   fib_prefix_t *prefix_out)
+{
+  clib_memcpy (&prefix_out->fp_addr, &prefix_in->name.as_ip46,
+	       sizeof (prefix_out->fp_addr));
+  prefix_out->fp_len = (u16) prefix_in->len;
+  prefix_out->fp_proto = ip46_address_is_ip4 (&prefix_out->fp_addr) ?
+				 FIB_PROTOCOL_IP4 :
+				 FIB_PROTOCOL_IP6;
+}
+
 /*
  * @brief Process incoming control messages (Interest Update)
  * @param vm vlib main data structure
@@ -167,46 +241,117 @@ hicn_mapme_nh_add (hicn_mapme_tfib_t *tfib, hicn_face_id_t face_id)
  */
 static_always_inline bool
 hicn_mapme_process_ctrl (vlib_main_t *vm, vlib_buffer_t *b,
-			 hicn_face_id_t in_face_id)
+			 hicn_face_id_t in_face_id, hicn_prefix_t *prefix,
+			 u32 *seq, hicn_mapme_type_t *type)
 {
   seq_t fib_seq;
-  const dpo_id_t *dpo;
-  hicn_prefix_t prefix;
+  const dpo_id_t *dpo, *dpo_mapme_default_route;
+  fib_prefix_t fib_prefix;
   mapme_params_t params;
+  hicn_mapme_tfib_t *tfib;
   int rc;
+  hicn_mapme_main_t *mm;
+#ifdef HICN_MAPME_ALLOW_NONEXISTING_FIB_ENTRY
+  fib_node_index_t fib_node_index;
+  hicn_mapme_tfib_t *tfib_less_specific;
+#endif
+
+  mm = hicn_mapme_get_main ();
 
   /* Parse incoming message */
-  rc = hicn_mapme_parse_packet (vlib_buffer_get_current (b), &prefix, &params);
+  rc = hicn_mapme_parse_packet (vlib_buffer_get_current (b), prefix, &params);
   if (rc < 0)
     goto ERR_PARSE;
 
-  vlib_cli_output (vm, "IU - type:%d seq:%d len:%d", params.type, params.seq,
-		   prefix.len);
+  *seq = params.seq;
+  *type = params.type;
 
-  /* if (params.seq == INVALID_SEQ) */
-  /*   { */
-  /*     vlib_log_warn (mapme_main.log_class, */
-  /*                 "Invalid sequence number found in IU"); */
-
-  /*     return true; */
-  /*   } */
+  HICN_DEBUG ("IU - type:%d seq:%d prefix:%U len:%d", params.type, params.seq,
+	      format_ip46_address, &prefix->name, IP46_TYPE_ANY, prefix->len);
 
   /* We forge the ACK which we be the packet forwarded by the node */
   hicn_mapme_create_ack (vlib_buffer_get_current (b), &params);
 
-  dpo = fib_epm_lookup (&prefix.name.as_ip46, prefix.len);
+  dpo = fib_lookup (&prefix->name.as_ip46, prefix->len,
+		    HICN_MAPME_FIB_LOOKUP_TYPE_EPM);
   if (!dpo)
     {
 #ifdef HICN_MAPME_ALLOW_NONEXISTING_FIB_ENTRY
-      /*
-       * This might happen for a node hosting a producer which has moved.
-       * Destroying the face has led to removing all corresponding FIB
-       * entries. In that case, we need to correctly restore the FIB entries.
-       */
-      HICN_DEBUG ("Re-creating FIB entry with next hop on connection")
-#error "not implemented"
+      // As the EPM failed (but we received the IU), it means we have another
+      // prefix that is either more or less specific to which forward
+      // the IU. We do not update the NHs for this prefix, and we use the
+      // default mapme route to forward ther IU.
+
+      dpo_mapme_default_route =
+	fib_lookup (&mm->default_route.fp_addr, mm->default_route.fp_len,
+		    HICN_MAPME_FIB_LOOKUP_TYPE_EPM);
+
+      if (!dpo_mapme_default_route)
+	{
+	  // No path for mapme default route.
+	  HICN_ERROR (
+	    "No path for mapme default route (%U). Giving up IU forwarding.",
+	    format_fib_prefix, &mm->default_route);
+	  return false;
+	}
+
+      hicn_prefix_to_fib_prefix (prefix, &fib_prefix);
+      HICN_DEBUG ("Re-creating FIB entry with next hop on connection");
+      rc = hicn_mapme_add_fib_entry (&fib_prefix, in_face_id, &fib_node_index);
+
+      if (rc != HICN_ERROR_NONE)
+	{
+	  return false;
+	}
+
+      // Get the DPO from the fib node index
+      dpo = dpo_from_fib_node_index (fib_node_index);
+
+      // This cannot fail
+      ASSERT (dpo);
+
+// Make sure DPO is hicn
+#ifdef HICN_MAPME_ALLOW_LOCATORS
+      if (!dpo_is_hicn ((dpo)))
+	{
+	  /* We have an IP DPO */
+	  HICN_ERROR ("Not implemented yet.");
+	  return false;
+	}
+#endif
+
+      u32 hicn_dpo_ctx_index = dpo->dpoi_index;
+      u32 hicn_dpo_ctx_index_less_specific_route =
+	dpo_mapme_default_route->dpoi_index;
+
+      tfib_less_specific = TFIB (
+	hicn_strategy_dpo_ctx_get (hicn_dpo_ctx_index_less_specific_route));
+      tfib = TFIB (hicn_strategy_dpo_ctx_get (hicn_dpo_ctx_index));
+
+      for (u8 pos = 0; pos < tfib_less_specific->entry_count; pos++)
+	{
+	  HICN_DEBUG (
+	    "Adding nexthop to the tfib, dpo index in_face %d, dpo index "
+	    "tfib %d",
+	    in_face_id, tfib_less_specific->next_hops[pos]);
+	  hicn_mapme_tfib_add (tfib, tfib_less_specific->next_hops[pos]);
+	}
+
+      // Update sequence number
+      tfib->seq = params.seq;
+
+      retx_t *retx = vlib_process_signal_event_data (
+	vm, hicn_mapme_eventmgr_process_node.index,
+	HICN_MAPME_EVENT_FACE_NH_SET, 1, sizeof (retx_t));
+      *retx = (retx_t){ .prefix = *prefix,
+			.dpo = {
+			  .dpoi_index = hicn_dpo_ctx_index,
+			  .dpoi_type = DPO_FIRST,
+			} };
+
+      return true;
 #else
-      // ERROR("Received IU for non-existing FIB entry");
+      HICN_ERROR ("Received IU for non-existing FIB entry");
       return false;
 #endif /* HICN_MAPME_ALLOW_NONEXISTING_FIB_ENTRY */
     }
@@ -221,7 +366,7 @@ hicn_mapme_process_ctrl (vlib_main_t *vm, vlib_buffer_t *b,
 #endif
 
   /* Process the hICN DPO */
-  hicn_mapme_tfib_t *tfib = TFIB (hicn_strategy_dpo_ctx_get (dpo->dpoi_index));
+  tfib = TFIB (hicn_strategy_dpo_ctx_get (dpo->dpoi_index));
 
   if (tfib == NULL)
     {
@@ -274,7 +419,7 @@ hicn_mapme_process_ctrl (vlib_main_t *vm, vlib_buffer_t *b,
       retx_t *retx = vlib_process_signal_event_data (
 	vm, hicn_mapme_eventmgr_process_node.index,
 	HICN_MAPME_EVENT_FACE_NH_SET, 1, sizeof (retx_t));
-      *retx = (retx_t){ .prefix = prefix, .dpo = *dpo };
+      *retx = (retx_t){ .prefix = *prefix, .dpo = *dpo };
     }
   else if (params.seq == fib_seq)
     {
@@ -298,7 +443,7 @@ hicn_mapme_process_ctrl (vlib_main_t *vm, vlib_buffer_t *b,
       retx_t *retx = vlib_process_signal_event_data (
 	vm, hicn_mapme_eventmgr_process_node.index,
 	HICN_MAPME_EVENT_FACE_NH_ADD, 1, sizeof (retx_t));
-      *retx = (retx_t){ .prefix = prefix, .dpo = *dpo };
+      *retx = (retx_t){ .prefix = *prefix, .dpo = *dpo };
     }
   else // params.seq < fib_seq
     {
@@ -320,7 +465,7 @@ hicn_mapme_process_ctrl (vlib_main_t *vm, vlib_buffer_t *b,
       retx_t *retx = vlib_process_signal_event_data (
 	vm, hicn_mapme_eventmgr_process_node.index,
 	HICN_MAPME_EVENT_FACE_PH_ADD, 1, sizeof (retx_t));
-      *retx = (retx_t){ .prefix = prefix, .dpo = *dpo };
+      *retx = (retx_t){ .prefix = *prefix, .dpo = *dpo };
     }
 
   /* We just raise events, the event_mgr is in charge of forging packet. */
@@ -343,6 +488,9 @@ hicn_mapme_ctrl_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
   u32 n_left_from, *from, *to_next;
   n_left_from = frame->n_vectors;
   // hicn_face_id_t in_face;
+  hicn_prefix_t prefix;
+  u32 seq;
+  hicn_mapme_type_t type;
 
   from = vlib_frame_vector_args (frame);
   n_left_from = frame->n_vectors;
@@ -370,12 +518,23 @@ hicn_mapme_ctrl_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
 
 	  /* This determines the next node on which the ack will be sent back
 	   */
-	  u32 next0 = hicn_mapme_ctrl_get_iface_node (hb->face_id);
+	  u32 next0 = HICN_MAPME_CTRL_NEXT_IP6_OUTPUT;
 
-	  hicn_mapme_process_ctrl (vm, b0, hb->face_id);
+	  hicn_mapme_process_ctrl (vm, b0, hb->face_id, &prefix, &seq, &type);
 
 	  vnet_buffer (b0)->ip.adj_index[VLIB_TX] = hb->face_id;
 
+	  if (PREDICT_FALSE ((node->flags & VLIB_NODE_FLAG_TRACE) &&
+			     (b0->flags & VLIB_BUFFER_IS_TRACED)))
+	    {
+	      hicn_mapme_ctrl_trace_t *t =
+		vlib_add_trace (vm, node, b0, sizeof (*t));
+	      t->prefix = prefix;
+	      t->next_index = next0;
+	      t->seq = seq;
+	      t->type = type;
+	    }
+
 	  vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
 					   n_left_to_next, bi0, next0);
 	}
@@ -395,8 +554,9 @@ hicn_mapme_ctrl_format_trace (u8 *s, va_list *args)
   CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
   hicn_mapme_ctrl_trace_t *t = va_arg (*args, hicn_mapme_ctrl_trace_t *);
 
-  s = format (s, "MAPME_CTRL: pkt: %d, sw_if_index %d, next index %d",
-	      (int) t->pkt_type, t->sw_if_index, t->next_index);
+  s = format (s, "MAPME_CTRL: prefix: %U/%d, next_index %u, seq %u, type %u",
+	      format_ip46_address, &t->prefix.name, IP46_TYPE_ANY,
+	      t->prefix.len, t->next_index, t->seq, t->type);
   return (s);
 }