fix(hicn-plugin): handle inflight interest coming from deleted face

Ticket: HICN-830

Change-Id: I14ed32bba2b07575ee604850080309706eb8ce85
Signed-off-by: Mauro Sardara <msardara@cisco.com>
(cherry picked from commit 64fa723904d35eda3406058469b890a39c3f628c)

4 files changed, 115 insertions, 46 deletions

diff --git a/hicn-plugin/src/data_fwd_node.c b/hicn-plugin/src/data_fwd_node.c
index dc1510fae..e3466c904 100644
--- a/hicn-plugin/src/data_fwd_node.c
+++ b/hicn-plugin/src/data_fwd_node.c
@@ -371,7 +371,15 @@ hicn_data_node_fn (vlib_main_t *vm, vlib_node_runtime_t *node,
 
 	  // Get PCS entry
 	  pcs_entry =
-	    hicn_pcs_entry_get_entry_from_index (rt->pitcs, pcs_entry_id);
+	    hicn_pcs_entry_get_entry_from_index_safe (rt->pitcs, pcs_entry_id);
+
+	  if (PREDICT_FALSE (pcs_entry == NULL))
+	    {
+	      drop_packet (vm, bi0, &n_left_to_next, &next0, &to_next,
+			   &next_index, node);
+
+	      goto end_processing;
+	    }
 
 	  isv6 = hicn_buffer_is_v6 (b0);
 
diff --git a/hicn-plugin/src/faces/face.h b/hicn-plugin/src/faces/face.h
index 99e3071af..b23cb9b12 100644
--- a/hicn-plugin/src/faces/face.h
+++ b/hicn-plugin/src/faces/face.h
@@ -518,6 +518,31 @@ hicn4_iface_adj_walk_cb (adj_index_t ai, void *ctx)
   return (ADJ_WALK_RC_CONTINUE);
 }
 
+always_inline int
+hicn_face_ip4_find (hicn_face_id_t *index, u8 *hicnb_flags,
+		    const ip4_address_t *nat_addr, u32 sw_if, u32 adj_index,
+		    u32 node_index)
+{
+  int ret = HICN_ERROR_FACE_NOT_FOUND;
+
+  /*All (complete) faces are indexed by remote addess as well */
+  /* if the face exists, it adds a lock */
+  hicn_face_t *face = hicn_face_get ((const ip46_address_t *) nat_addr, sw_if,
+				     &hicn_face_hashtb, adj_index);
+
+  if (face != NULL)
+    {
+      /* unlock the face. We don't take a lock on each interest we receive */
+      hicn_face_id_t face_id = hicn_dpoi_get_index (face);
+      hicn_face_unlock_with_id (face_id);
+      ret = HICN_ERROR_FACE_ALREADY_CREATED;
+      *hicnb_flags = HICN_BUFFER_FLAGS_DEFAULT;
+      *index = hicn_dpoi_get_index (face);
+    }
+
+  return ret;
+}
+
 /**
  * @brief Retrieve, or create if it doesn't exist, a face from the ip6 local
  * address and returns its dpo. This method adds a lock on the face state.
@@ -535,17 +560,16 @@ hicn_face_ip4_add_and_lock (hicn_face_id_t *index, u8 *hicnb_flags,
 			    u32 adj_index, u32 node_index)
 {
   int ret = HICN_ERROR_NONE;
-  /*All (complete) faces are indexed by remote addess as well */
-
-  ip46_address_t ip_address = { 0 };
-  ip46_address_set_ip4 (&ip_address, nat_addr);
+  hicn_face_t *face = NULL;
 
-  /* if the face exists, it adds a lock */
-  hicn_face_t *face =
-    hicn_face_get (&ip_address, sw_if, &hicn_face_hashtb, adj_index);
+  ret = hicn_face_ip4_find (index, hicnb_flags, nat_addr, sw_if, adj_index,
+			    node_index);
 
-  if (face == NULL)
+  if (ret == HICN_ERROR_FACE_NOT_FOUND)
     {
+      ip46_address_t ip_address = { 0 };
+      ip46_address_set_ip4 (&ip_address, nat_addr);
+
       hicn_face_id_t idx;
       u8 face_flags = 0;
 
@@ -566,15 +590,6 @@ hicn_face_ip4_add_and_lock (hicn_face_id_t *index, u8 *hicnb_flags,
 
       *index = idx;
     }
-  else
-    {
-      /* unlock the face. We don't take a lock on each interest we receive */
-      hicn_face_id_t face_id = hicn_dpoi_get_index (face);
-      hicn_face_unlock_with_id (face_id);
-      ret = HICN_ERROR_FACE_ALREADY_CREATED;
-      *index = hicn_dpoi_get_index (face);
-      *hicnb_flags = HICN_BUFFER_FLAGS_DEFAULT;
-    }
 
   return ret;
 }
@@ -600,6 +615,29 @@ hicn6_iface_adj_walk_cb (adj_index_t ai, void *ctx)
   return (ADJ_WALK_RC_CONTINUE);
 }
 
+always_inline int
+hicn_face_ip6_find (hicn_face_id_t *index, u8 *hicnb_flags,
+		    const ip6_address_t *nat_addr, u32 sw_if, u32 adj_index,
+		    u32 node_index)
+{
+  int ret = HICN_ERROR_FACE_NOT_FOUND;
+
+  hicn_face_t *face = hicn_face_get ((const ip46_address_t *) nat_addr, sw_if,
+				     &hicn_face_hashtb, adj_index);
+
+  if (face != NULL)
+    {
+      /* unlock the face. We don't take a lock on each interest we receive */
+      hicn_face_id_t face_id = hicn_dpoi_get_index (face);
+      hicn_face_unlock_with_id (face_id);
+      ret = HICN_ERROR_FACE_ALREADY_CREATED;
+      *hicnb_flags = HICN_BUFFER_FLAGS_DEFAULT;
+      *index = hicn_dpoi_get_index (face);
+    }
+
+  return ret;
+}
+
 /**
  * @brief Retrieve, or create if it doesn't exist, a face from the ip6 local
  * address and returns its dpo. This method adds a lock on the face state.
@@ -617,14 +655,15 @@ hicn_face_ip6_add_and_lock (hicn_face_id_t *index, u8 *hicnb_flags,
 			    u32 adj_index, u32 node_index)
 {
   int ret = HICN_ERROR_NONE;
+  hicn_face_t *face = NULL;
 
-  /*All (complete) faces are indexed by remote addess as well */
-  /* if the face exists, it adds a lock */
-  hicn_face_t *face = hicn_face_get ((const ip46_address_t *) nat_addr, sw_if,
-				     &hicn_face_hashtb, adj_index);
+  ret = hicn_face_ip6_find (index, hicnb_flags, nat_addr, sw_if, adj_index,
+			    node_index);
 
-  if (face == NULL)
+  if (ret == HICN_ERROR_FACE_NOT_FOUND)
     {
+      ip46_address_t ip_address = { 0 };
+      ip46_address_set_ip6 (&ip_address, nat_addr);
       hicn_face_id_t idx;
       u8 face_flags = 0;
 
@@ -640,15 +679,6 @@ hicn_face_ip6_add_and_lock (hicn_face_id_t *index, u8 *hicnb_flags,
       *hicnb_flags = HICN_BUFFER_FLAGS_NEW_FACE;
       *index = idx;
     }
-  else
-    {
-      /* unlock the face. We don't take a lock on each interest we receive */
-      hicn_face_id_t face_id = hicn_dpoi_get_index (face);
-      hicn_face_unlock_with_id (face_id);
-      ret = HICN_ERROR_FACE_ALREADY_CREATED;
-      *hicnb_flags = HICN_BUFFER_FLAGS_DEFAULT;
-      *index = hicn_dpoi_get_index (face);
-    }
 
   return ret;
 }
diff --git a/hicn-plugin/src/faces/face_node.c b/hicn-plugin/src/faces/face_node.c
index 0d2e70fbe..ab51293b3 100644
--- a/hicn-plugin/src/faces/face_node.c
+++ b/hicn-plugin/src/faces/face_node.c
@@ -164,12 +164,15 @@ typedef enum
 	    (from_tunnel0) * ~0 +                                             \
 	    (1 - from_tunnel0) * vnet_buffer (b0)->sw_if_index[VLIB_RX];      \
                                                                               \
-	  ret0 = hicn_face_ip##ipv##_add_and_lock (                           \
+	  ret0 = hicn_face_ip##ipv##_find (                                   \
 	    &hicnb0->face_id, &hicnb0->flags, &ip_hdr->dst_address, sw_if0,   \
 	    vnet_buffer (b0)->ip.adj_index[VLIB_RX],                          \
 	    /* Should not be used */ ~0);                                     \
 	  /* Make sure the face is not created here */                        \
-	  ASSERT (ret0 == HICN_ERROR_FACE_ALREADY_CREATED);                   \
+	  if (PREDICT_FALSE (ret0 == HICN_ERROR_FACE_NOT_FOUND))              \
+	    {                                                                 \
+	      next0 = HICN##ipv##_FACE_INPUT_NEXT_ERROR_DROP;                 \
+	    }                                                                 \
 	}                                                                     \
                                                                               \
       vlib_increment_combined_counter (                                       \
@@ -261,12 +264,15 @@ typedef enum
 	    (from_tunnel0) * ~0 +                                             \
 	    (1 - from_tunnel0) * vnet_buffer (b0)->sw_if_index[VLIB_RX];      \
                                                                               \
-	  ret0 = hicn_face_ip##ipv##_add_and_lock (                           \
+	  ret0 = hicn_face_ip##ipv##_find (                                   \
 	    &hicnb0->face_id, &hicnb0->flags, &ip_hdr0->dst_address, sw_if0,  \
 	    vnet_buffer (b0)->ip.adj_index[VLIB_RX],                          \
 	    /* Should not be used */ ~0);                                     \
 	  /* Make sure the face is not created here */                        \
-	  ASSERT (ret0 == HICN_ERROR_FACE_ALREADY_CREATED);                   \
+	  if (PREDICT_FALSE (ret0 == HICN_ERROR_FACE_NOT_FOUND))              \
+	    {                                                                 \
+	      next0 = HICN##ipv##_FACE_INPUT_NEXT_ERROR_DROP;                 \
+	    }                                                                 \
                                                                               \
 	  from_tunnel1 =                                                      \
 	    (hicnb1->flags & HICN_BUFFER_FLAGS_FROM_UDP4_TUNNEL ||            \
@@ -275,12 +281,15 @@ typedef enum
 	    (from_tunnel1) * ~0 +                                             \
 	    (1 - from_tunnel1) * vnet_buffer (b1)->sw_if_index[VLIB_RX];      \
                                                                               \
-	  ret1 = hicn_face_ip##ipv##_add_and_lock (                           \
+	  ret1 = hicn_face_ip##ipv##_find (                                   \
 	    &hicnb1->face_id, &hicnb1->flags, &ip_hdr1->dst_address, sw_if1,  \
 	    vnet_buffer (b1)->ip.adj_index[VLIB_RX],                          \
 	    /* Should not be used */ ~0);                                     \
 	  /* Make sure the face is not created here */                        \
-	  ASSERT (ret1 == HICN_ERROR_FACE_ALREADY_CREATED);                   \
+	  if (PREDICT_FALSE (ret1 == HICN_ERROR_FACE_NOT_FOUND))              \
+	    {                                                                 \
+	      next1 = HICN##ipv##_FACE_INPUT_NEXT_ERROR_DROP;                 \
+	    }                                                                 \
 	}                                                                     \
       else if (ret0 && !ret1)                                                 \
 	{                                                                     \
@@ -292,14 +301,20 @@ typedef enum
 	    (from_tunnel0) * ~0 +                                             \
 	    (1 - from_tunnel0) * vnet_buffer (b0)->sw_if_index[VLIB_RX];      \
                                                                               \
-	  ret0 = hicn_face_ip##ipv##_add_and_lock (                           \
+	  ret0 = hicn_face_ip##ipv##_find (                                   \
 	    &hicnb0->face_id, &hicnb0->flags, &ip_hdr0->dst_address, sw_if0,  \
 	    vnet_buffer (b0)->ip.adj_index[VLIB_RX],                          \
 	    /* Should not be used */ ~0);                                     \
 	  /* Make sure the face is not created here */                        \
-	  ASSERT (ret0 == HICN_ERROR_FACE_ALREADY_CREATED);                   \
-	  next0 = is_icmp0 * NEXT_MAPME_IP##ipv +                             \
-		  (1 - is_icmp0) * NEXT_DATA_IP##ipv;                         \
+	  if (PREDICT_FALSE (ret0 == HICN_ERROR_FACE_NOT_FOUND))              \
+	    {                                                                 \
+	      next0 = HICN##ipv##_FACE_INPUT_NEXT_ERROR_DROP;                 \
+	    }                                                                 \
+	  else                                                                \
+	    {                                                                 \
+	      next0 = is_icmp0 * NEXT_MAPME_IP##ipv +                         \
+		      (1 - is_icmp0) * NEXT_DATA_IP##ipv;                     \
+	    }                                                                 \
 	}                                                                     \
       else if (!ret0 && ret1)                                                 \
 	{                                                                     \
@@ -311,14 +326,20 @@ typedef enum
 	    (from_tunnel1) * ~0 +                                             \
 	    (1 - from_tunnel1) * vnet_buffer (b1)->sw_if_index[VLIB_RX];      \
                                                                               \
-	  ret1 = hicn_face_ip##ipv##_add_and_lock (                           \
+	  ret1 = hicn_face_ip##ipv##_find (                                   \
 	    &hicnb1->face_id, &hicnb1->flags, &ip_hdr1->dst_address, sw_if1,  \
 	    vnet_buffer (b1)->ip.adj_index[VLIB_RX],                          \
 	    /* Should not be used */ ~0);                                     \
 	  /* Make sure the face is not created here */                        \
-	  ASSERT (ret1 == HICN_ERROR_FACE_ALREADY_CREATED);                   \
-	  next1 = is_icmp1 * NEXT_MAPME_IP##ipv +                             \
-		  (1 - is_icmp1) * NEXT_DATA_IP##ipv;                         \
+	  if (PREDICT_FALSE (ret1 == HICN_ERROR_FACE_NOT_FOUND))              \
+	    {                                                                 \
+	      next1 = HICN##ipv##_FACE_INPUT_NEXT_ERROR_DROP;                 \
+	    }                                                                 \
+	  else                                                                \
+	    {                                                                 \
+	      next1 = is_icmp1 * NEXT_MAPME_IP##ipv +                         \
+		      (1 - is_icmp1) * NEXT_DATA_IP##ipv;                     \
+	    }                                                                 \
 	}                                                                     \
       else                                                                    \
 	{                                                                     \
diff --git a/hicn-plugin/src/pcs.h b/hicn-plugin/src/pcs.h
index 0b7635100..86fb72cc9 100644
--- a/hicn-plugin/src/pcs.h
+++ b/hicn-plugin/src/pcs.h
@@ -377,6 +377,16 @@ hicn_pcs_entry_get_entry_from_index (const hicn_pit_cs_t *pitcs, u32 index)
   return pool_elt_at_index (pitcs->pcs_entries_pool, index);
 }
 
+always_inline hicn_pcs_entry_t *
+hicn_pcs_entry_get_entry_from_index_safe (const hicn_pit_cs_t *pitcs,
+					  u32 index)
+{
+  if (!pool_is_free_index (pitcs->pcs_entries_pool, index))
+    return pool_elt_at_index (pitcs->pcs_entries_pool, index);
+
+  return NULL;
+}
+
 /*
  * Check if pcs entry is a content store entry
  */