fib: Decouple source from priority and behaviour

Type: feature

the fib_source_t enum alone no longer defines the priority and
behaviour, instead each source must be allocated these attributes.
This allows the creation of other sources by the plugins (and
soon over the API).

Signed-off-by: Neale Ranns <nranns@cisco.com>
Change-Id: I890ee820fbc16079ee417ea1fbc163192806e853

14 files changed, 119 insertions, 63 deletions

diff --git a/src/plugins/gbp/gbp_endpoint.c b/src/plugins/gbp/gbp_endpoint.c
index 12865461d18..bef67770fd9 100644
--- a/src/plugins/gbp/gbp_endpoint.c
+++ b/src/plugins/gbp/gbp_endpoint.c
@@ -41,9 +41,10 @@ static const char *gbp_endpoint_attr_names[] = GBP_ENDPOINT_ATTR_NAMES;
  */
 gbp_ep_db_t gbp_ep_db;
 
-fib_node_type_t gbp_endpoint_fib_type;
-
-vlib_log_class_t gbp_ep_logger;
+static fib_source_t gbp_fib_source_hi;
+static fib_source_t gbp_fib_source_low;
+static fib_node_type_t gbp_endpoint_fib_type;
+static vlib_log_class_t gbp_ep_logger;
 
 #define GBP_ENDPOINT_DBG(...)                           \
     vlib_log_debug (gbp_ep_logger, __VA_ARGS__);
@@ -588,10 +589,10 @@ gbb_endpoint_fwd_reset (gbp_endpoint_t * ge)
      */
     if (gbp_endpoint_is_remote (ge))
       {
-	fib_table_entry_special_remove (fib_index, pfx, FIB_SOURCE_PLUGIN_HI);
+	fib_table_entry_special_remove (fib_index, pfx, gbp_fib_source_hi);
       }
 
-    fib_table_entry_delete (fib_index, pfx, FIB_SOURCE_PLUGIN_LOW);
+    fib_table_entry_delete (fib_index, pfx, gbp_fib_source_low);
   }
   vec_foreach (ai, gef->gef_adjs)
   {
@@ -726,7 +727,7 @@ gbb_endpoint_fwd_recalc (gbp_endpoint_t * ge)
       }
 
     fib_table_entry_path_add (fib_index, pfx,
-			      FIB_SOURCE_PLUGIN_LOW,
+			      gbp_fib_source_low,
 			      FIB_ENTRY_FLAG_NONE,
 			      fib_proto_to_dpo (pfx->fp_proto),
 			      &pfx->fp_addr, ip_sw_if_index,
@@ -759,7 +760,7 @@ gbb_endpoint_fwd_recalc (gbp_endpoint_t * ge)
 					gg->gg_sclass, ~0, &policy_dpo);
 
 	    fib_table_entry_special_dpo_add (fib_index, pfx,
-					     FIB_SOURCE_PLUGIN_HI,
+					     gbp_fib_source_hi,
 					     FIB_ENTRY_FLAG_INTERPOSE,
 					     &policy_dpo);
 	    dpo_reset (&policy_dpo);
@@ -1576,6 +1577,12 @@ gbp_endpoint_init (vlib_main_t * vm)
 
   gbp_ep_logger = vlib_log_register_class ("gbp", "ep");
   gbp_endpoint_fib_type = fib_node_register_new_type (&gbp_endpoint_vft);
+  gbp_fib_source_hi = fib_source_allocate ("gbp-endpoint-hi",
+					   FIB_SOURCE_PRIORITY_HI,
+					   FIB_SOURCE_BH_SIMPLE);
+  gbp_fib_source_low = fib_source_allocate ("gbp-endpoint-low",
+					    FIB_SOURCE_PRIORITY_LOW,
+					    FIB_SOURCE_BH_SIMPLE);
 
   return (NULL);
 }
diff --git a/src/plugins/gbp/gbp_route_domain.c b/src/plugins/gbp/gbp_route_domain.c
index ab998591982..f0aa694d44a 100644
--- a/src/plugins/gbp/gbp_route_domain.c
+++ b/src/plugins/gbp/gbp_route_domain.c
@@ -53,6 +53,7 @@ typedef struct gbp_route_domain_db_t
 } gbp_route_domain_db_t;
 
 static gbp_route_domain_db_t gbp_route_domain_db;
+static fib_source_t gbp_fib_source;
 
 /**
  * logger
@@ -154,7 +155,7 @@ gbp_route_domain_add_and_lock (u32 rd_id,
 	grd->grd_fib_index[fproto] =
 	  fib_table_find_or_create_and_lock (fproto,
 					     grd->grd_table_id[fproto],
-					     FIB_SOURCE_PLUGIN_HI);
+					     gbp_fib_source);
 
 	if (~0 != grd->grd_uu_sw_if_index[fproto])
 	  {
@@ -221,8 +222,7 @@ gbp_route_domain_unlock (index_t index)
 
       FOR_EACH_FIB_IP_PROTOCOL (fproto)
       {
-	fib_table_unlock (grd->grd_fib_index[fproto],
-			  fproto, FIB_SOURCE_PLUGIN_HI);
+	fib_table_unlock (grd->grd_fib_index[fproto], fproto, gbp_fib_source);
 	if (INDEX_INVALID != grd->grd_adj[fproto])
 	  adj_unlock (grd->grd_adj[fproto]);
       }
@@ -430,6 +430,9 @@ static clib_error_t *
 gbp_route_domain_init (vlib_main_t * vm)
 {
   grd_logger = vlib_log_register_class ("gbp", "rd");
+  gbp_fib_source = fib_source_allocate ("gbp-rd",
+					FIB_SOURCE_PRIORITY_HI,
+					FIB_SOURCE_BH_DROP);
 
   return (NULL);
 }
diff --git a/src/plugins/gbp/gbp_subnet.c b/src/plugins/gbp/gbp_subnet.c
index bb069ffe892..2ef3fcfd534 100644
--- a/src/plugins/gbp/gbp_subnet.c
+++ b/src/plugins/gbp/gbp_subnet.c
@@ -65,6 +65,8 @@ uword *gbp_subnet_db;
  */
 gbp_subnet_t *gbp_subnet_pool;
 
+static fib_source_t gbp_fib_source;
+
 static index_t
 gbp_subnet_db_find (u32 fib_index, const fib_prefix_t * pfx)
 {
@@ -122,7 +124,7 @@ gbp_subnet_transport_add (gbp_subnet_t * gs)
 
   gs->gs_fei = fib_table_entry_update_one_path (gs->gs_key->gsk_fib_index,
 						&gs->gs_key->gsk_pfx,
-						FIB_SOURCE_PLUGIN_HI,
+						gbp_fib_source,
 						FIB_ENTRY_FLAG_NONE,
 						fib_proto_to_dpo (fproto),
 						&ADJ_BCAST_ADDR,
@@ -145,7 +147,7 @@ gbp_subnet_internal_add (gbp_subnet_t * gs)
 
   gs->gs_fei = fib_table_entry_special_dpo_update (gs->gs_key->gsk_fib_index,
 						   &gs->gs_key->gsk_pfx,
-						   FIB_SOURCE_PLUGIN_HI,
+						   gbp_fib_source,
 						   FIB_ENTRY_FLAG_EXCLUSIVE,
 						   &gfd);
 
@@ -169,7 +171,7 @@ gbp_subnet_external_add (gbp_subnet_t * gs, u32 sw_if_index, sclass_t sclass)
 
   gs->gs_fei = fib_table_entry_special_dpo_update (gs->gs_key->gsk_fib_index,
 						   &gs->gs_key->gsk_pfx,
-						   FIB_SOURCE_PLUGIN_HI,
+						   gbp_fib_source,
 						   (FIB_ENTRY_FLAG_EXCLUSIVE |
 						    FIB_ENTRY_FLAG_LOOSE_URPF_EXEMPT),
 						   &gpd);
@@ -216,7 +218,7 @@ gbp_subnet_del_i (index_t gsi)
 				(GBP_SUBNET_L3_OUT == gs->gs_type
 				 || GBP_SUBNET_ANON_L3_OUT ==
 				 gs->gs_type) ? FIB_SOURCE_SPECIAL :
-				FIB_SOURCE_PLUGIN_HI);
+				gbp_fib_source);
 
   gbp_subnet_db_del (gs);
   gbp_route_domain_unlock (gs->gs_rd);
@@ -578,6 +580,9 @@ gbp_subnet_init (vlib_main_t * vm)
 {
   gbp_subnet_db = hash_create_mem (0,
 				   sizeof (gbp_subnet_key_t), sizeof (u32));
+  gbp_fib_source = fib_source_allocate ("gbp-subnet",
+					FIB_SOURCE_PRIORITY_HI,
+					FIB_SOURCE_BH_SIMPLE);
 
   return (NULL);
 }
diff --git a/src/plugins/ila/ila.c b/src/plugins/ila/ila.c
index bac76151c28..162d417d772 100644
--- a/src/plugins/ila/ila.c
+++ b/src/plugins/ila/ila.c
@@ -68,6 +68,11 @@ static dpo_type_t ila_dpo_type;
  */
 static fib_node_type_t ila_fib_node_type;
 
+/**
+ * FIB source for adding entries
+ */
+static fib_source_t ila_fib_src;
+
 u8 *
 format_half_ip6_address (u8 * s, va_list * va)
 {
@@ -758,7 +763,7 @@ ila_add_del_entry (ila_add_del_entry_args_t * args)
 
 	  fib_table_entry_special_dpo_add(0,
 					  &pfx,
-					  FIB_SOURCE_PLUGIN_HI,
+					  ila_fib_src,
 					  FIB_ENTRY_FLAG_EXCLUSIVE,
 					  &dpo);
 	  dpo_reset(&dpo);
@@ -794,7 +799,7 @@ ila_add_del_entry (ila_add_del_entry_args_t * args)
 	      .fp_proto = FIB_PROTOCOL_IP6,
 	  };
 
-	  fib_table_entry_special_remove(0, &pfx, FIB_SOURCE_PLUGIN_HI);
+	  fib_table_entry_special_remove(0, &pfx, ila_fib_src);
 	  /*
 	   * remove this ILA entry as child of the FIB netry for the next-hop
 	   */
@@ -935,7 +940,9 @@ ila_init (vlib_main_t * vm)
 
   ila_dpo_type = dpo_register_new_type(&ila_vft, ila_nodes);
   ila_fib_node_type = fib_node_register_new_type(&ila_fib_node_vft);
-
+  ila_fib_src = fib_source_allocate("ila",
+                                    FIB_SOURCE_PRIORITY_HI,
+                                    FIB_SOURCE_BH_SIMPLE);
   return NULL;
 }
 
diff --git a/src/plugins/lb/lb.c b/src/plugins/lb/lb.c
index b1e0b237478..4dbf134cc4f 100644
--- a/src/plugins/lb/lb.c
+++ b/src/plugins/lb/lb.c
@@ -26,6 +26,9 @@
 //After so many seconds. It is assumed that inter-core race condition will not occur.
 #define LB_CONCURRENCY_TIMEOUT 10
 
+// FIB source for adding routes
+static fib_source_t lb_fib_src;
+
 lb_main_t lb_main;
 
 #define lb_get_writer_lock() clib_spinlock_lock (&lb_main.writer_lock)
@@ -948,7 +951,7 @@ static void lb_vip_add_adjacency(lb_main_t *lbm, lb_vip_t *vip,
   dpo_set(&dpo, dpo_type, proto, *vip_prefix_index);
   fib_table_entry_special_dpo_add(0,
                                   &pfx,
-                                  FIB_SOURCE_PLUGIN_HI,
+                                  lb_fib_src,
                                   FIB_ENTRY_FLAG_EXCLUSIVE,
                                   &dpo);
   dpo_reset(&dpo);
@@ -1037,7 +1040,7 @@ static void lb_vip_del_adjacency(lb_main_t *lbm, lb_vip_t *vip)
       pfx.fp_len = vip->plen;
       pfx.fp_proto = FIB_PROTOCOL_IP6;
   }
-  fib_table_entry_special_remove(0, &pfx, FIB_SOURCE_PLUGIN_HI);
+  fib_table_entry_special_remove(0, &pfx, lb_fib_src);
 }
 
 int lb_vip_add(lb_vip_add_args_t args, u32 *vip_index)
@@ -1445,6 +1448,11 @@ lb_init (vlib_main_t * vm)
 #define _(a,b,c) lbm->vip_counters[c].name = b;
   lb_foreach_vip_counter
 #undef _
+
+  lb_fib_src = fib_source_allocate("lb",
+                                   FIB_SOURCE_PRIORITY_HI,
+                                   FIB_SOURCE_BH_SIMPLE);
+
   return NULL;
 }
 
diff --git a/src/plugins/nat/dslite.c b/src/plugins/nat/dslite.c
index 339c12c5656..d9a17293fac 100644
--- a/src/plugins/nat/dslite.c
+++ b/src/plugins/nat/dslite.c
@@ -109,7 +109,7 @@ dslite_set_aftr_ip6_addr (dslite_main_t * dm, ip6_address_t * addr)
 	.fp_len = 0,
 	.fp_addr.ip4.as_u32 = 0,
       };
-      fib_table_entry_special_dpo_add (0, &pfx, FIB_SOURCE_PLUGIN_HI,
+      fib_table_entry_special_dpo_add (0, &pfx, nat_fib_src_hi,
 				       FIB_ENTRY_FLAG_EXCLUSIVE, &dpo);
     }
   else
@@ -121,7 +121,7 @@ dslite_set_aftr_ip6_addr (dslite_main_t * dm, ip6_address_t * addr)
 	.fp_addr.ip6.as_u64[0] = addr->as_u64[0],
 	.fp_addr.ip6.as_u64[1] = addr->as_u64[1],
       };
-      fib_table_entry_special_dpo_add (0, &pfx, FIB_SOURCE_PLUGIN_HI,
+      fib_table_entry_special_dpo_add (0, &pfx, nat_fib_src_hi,
 				       FIB_ENTRY_FLAG_EXCLUSIVE, &dpo);
     }
 
@@ -153,7 +153,7 @@ dslite_set_b4_ip6_addr (dslite_main_t * dm, ip6_address_t * addr)
 	.fp_addr.ip6.as_u64[0] = addr->as_u64[0],
 	.fp_addr.ip6.as_u64[1] = addr->as_u64[1],
       };
-      fib_table_entry_special_dpo_add (0, &pfx, FIB_SOURCE_PLUGIN_HI,
+      fib_table_entry_special_dpo_add (0, &pfx, nat_fib_src_hi,
 				       FIB_ENTRY_FLAG_EXCLUSIVE, &dpo);
 
       dpo_reset (&dpo);
@@ -218,7 +218,7 @@ dslite_add_del_pool_addr (dslite_main_t * dm, ip4_address_t * addr, u8 is_add)
       foreach_snat_protocol
 #undef _
 	dslite_dpo_create (DPO_PROTO_IP4, 0, &dpo_v4);
-      fib_table_entry_special_dpo_add (0, &pfx, FIB_SOURCE_PLUGIN_HI,
+      fib_table_entry_special_dpo_add (0, &pfx, nat_fib_src_hi,
 				       FIB_ENTRY_FLAG_EXCLUSIVE, &dpo_v4);
       dpo_reset (&dpo_v4);
     }
@@ -231,7 +231,7 @@ dslite_add_del_pool_addr (dslite_main_t * dm, ip4_address_t * addr, u8 is_add)
       vec_free (a->busy_##n##_ports_per_thread);
       foreach_snat_protocol
 #undef _
-	fib_table_entry_special_remove (0, &pfx, FIB_SOURCE_PLUGIN_HI);
+	fib_table_entry_special_remove (0, &pfx, nat_fib_src_hi);
       vec_del1 (dm->addr_pool, i);
     }
   return 0;
diff --git a/src/plugins/nat/nat.c b/src/plugins/nat/nat.c
index 0a30caf0f21..d7133684b32 100755
--- a/src/plugins/nat/nat.c
+++ b/src/plugins/nat/nat.c
@@ -38,6 +38,9 @@
 
 snat_main_t snat_main;
 
+fib_source_t nat_fib_src_hi;
+fib_source_t nat_fib_src_low;
+
 /* *INDENT-OFF* */
 /* Hook up input features */
 VNET_FEATURE_INIT (nat_pre_in2out, static) = {
@@ -536,7 +539,7 @@ snat_add_del_addr_to_fib (ip4_address_t * addr, u8 p_len, u32 sw_if_index,
   if (is_add)
     fib_table_entry_update_one_path (fib_index,
 				     &prefix,
-				     FIB_SOURCE_PLUGIN_LOW,
+				     nat_fib_src_low,
 				     (FIB_ENTRY_FLAG_CONNECTED |
 				      FIB_ENTRY_FLAG_LOCAL |
 				      FIB_ENTRY_FLAG_EXCLUSIVE),
@@ -545,7 +548,7 @@ snat_add_del_addr_to_fib (ip4_address_t * addr, u8 p_len, u32 sw_if_index,
 				     sw_if_index,
 				     ~0, 1, NULL, FIB_ROUTE_PATH_FLAG_NONE);
   else
-    fib_table_entry_delete (fib_index, &prefix, FIB_SOURCE_PLUGIN_LOW);
+    fib_table_entry_delete (fib_index, &prefix, nat_fib_src_low);
 }
 
 int
@@ -577,7 +580,7 @@ snat_add_address (snat_main_t * sm, ip4_address_t * addr, u32 vrf_id,
   if (vrf_id != ~0)
     ap->fib_index =
       fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4, vrf_id,
-					 FIB_SOURCE_PLUGIN_LOW);
+					 nat_fib_src_low);
   else
     ap->fib_index = ~0;
 #define _(N, i, n, s) \
@@ -813,7 +816,7 @@ snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
 	      local->vrf_id = vrf_id;
 	      local->fib_index =
 		fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4, vrf_id,
-						   FIB_SOURCE_PLUGIN_LOW);
+						   nat_fib_src_low);
 	      m_key.addr = m->local_addr;
 	      m_key.port = m->local_port;
 	      m_key.protocol = m->proto;
@@ -834,13 +837,13 @@ snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
       if (vrf_id != ~0)
 	fib_index =
 	  fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4, vrf_id,
-					     FIB_SOURCE_PLUGIN_LOW);
+					     nat_fib_src_low);
       /* If not specified use inside VRF id from SNAT plugin startup config */
       else
 	{
 	  fib_index = sm->inside_fib_index;
 	  vrf_id = sm->inside_vrf_id;
-	  fib_table_lock (fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_PLUGIN_LOW);
+	  fib_table_lock (fib_index, FIB_PROTOCOL_IP4, nat_fib_src_low);
 	}
 
       if (!(out2in_only || identity_nat))
@@ -1133,7 +1136,7 @@ snat_add_static_mapping (ip4_address_t l_addr, ip4_address_t e_addr,
 	    }
 	}
 
-      fib_table_unlock (fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_PLUGIN_LOW);
+      fib_table_unlock (fib_index, FIB_PROTOCOL_IP4, nat_fib_src_low);
       if (pool_elts (m->locals))
 	return 0;
 
@@ -1291,7 +1294,7 @@ nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
 	  locals[i].fib_index =
 	    fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4,
 					       locals[i].vrf_id,
-					       FIB_SOURCE_PLUGIN_LOW);
+					       nat_fib_src_low);
 	  m_key.addr = locals[i].addr;
 	  m_key.fib_index = locals[i].fib_index;
 	  if (!out2in_only)
@@ -1381,7 +1384,7 @@ nat44_add_del_lb_static_mapping (ip4_address_t e_addr, u16 e_port,
       pool_foreach (local, m->locals,
       ({
           fib_table_unlock (local->fib_index, FIB_PROTOCOL_IP4,
-                            FIB_SOURCE_PLUGIN_LOW);
+                            nat_fib_src_low);
           m_key.addr = local->addr;
           if (!out2in_only)
             {
@@ -1514,7 +1517,7 @@ nat44_lb_static_mapping_add_del_local (ip4_address_t e_addr, u16 e_port,
       local->vrf_id = vrf_id;
       local->fib_index =
 	fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4, vrf_id,
-					   FIB_SOURCE_PLUGIN_LOW);
+					   nat_fib_src_low);
 
       if (!is_out2in_only_static_mapping (m))
 	{
@@ -1536,7 +1539,7 @@ nat44_lb_static_mapping_add_del_local (ip4_address_t e_addr, u16 e_port,
 	return VNET_API_ERROR_UNSPECIFIED;
 
       fib_table_unlock (match_local->fib_index, FIB_PROTOCOL_IP4,
-			FIB_SOURCE_PLUGIN_LOW);
+			nat_fib_src_low);
 
       if (!is_out2in_only_static_mapping (m))
 	{
@@ -1687,7 +1690,7 @@ snat_del_address (snat_main_t * sm, ip4_address_t addr, u8 delete_sm,
     }
 
   if (a->fib_index != ~0)
-    fib_table_unlock (a->fib_index, FIB_PROTOCOL_IP4, FIB_SOURCE_PLUGIN_LOW);
+    fib_table_unlock (a->fib_index, FIB_PROTOCOL_IP4, nat_fib_src_low);
 
   /* Delete sessions using address */
   if (a->busy_tcp_ports || a->busy_udp_ports || a->busy_icmp_ports)
@@ -2464,6 +2467,13 @@ snat_init (vlib_main_t * vm)
   };
   vec_add1 (ip4_main.table_bind_callbacks, cbt4);
 
+  nat_fib_src_hi = fib_source_allocate ("nat-hi",
+					FIB_SOURCE_PRIORITY_HI,
+					FIB_SOURCE_BH_SIMPLE);
+  nat_fib_src_low = fib_source_allocate ("nat-low",
+					 FIB_SOURCE_PRIORITY_LOW,
+					 FIB_SOURCE_BH_SIMPLE);
+
   /* Init virtual fragmenentation reassembly */
   return nat_reass_init (vm);
 }
@@ -2915,13 +2925,13 @@ nat44_add_del_address_dpo (ip4_address_t addr, u8 is_add)
   if (is_add)
     {
       nat_dpo_create (DPO_PROTO_IP4, 0, &dpo_v4);
-      fib_table_entry_special_dpo_add (0, &pfx, FIB_SOURCE_PLUGIN_HI,
+      fib_table_entry_special_dpo_add (0, &pfx, nat_fib_src_hi,
 				       FIB_ENTRY_FLAG_EXCLUSIVE, &dpo_v4);
       dpo_reset (&dpo_v4);
     }
   else
     {
-      fib_table_entry_special_remove (0, &pfx, FIB_SOURCE_PLUGIN_HI);
+      fib_table_entry_special_remove (0, &pfx, nat_fib_src_hi);
     }
 }
 
@@ -3836,15 +3846,15 @@ snat_config (vlib_main_t * vm, unformat_input_t * input)
   sm->outside_vrf_id = outside_vrf_id;
   sm->outside_fib_index = fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4,
 							     outside_vrf_id,
-							     FIB_SOURCE_PLUGIN_HI);
+							     nat_fib_src_hi);
   nm->outside_vrf_id = outside_ip6_vrf_id;
   nm->outside_fib_index = fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP6,
 							     outside_ip6_vrf_id,
-							     FIB_SOURCE_PLUGIN_HI);
+							     nat_fib_src_hi);
   sm->inside_vrf_id = inside_vrf_id;
   sm->inside_fib_index = fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP4,
 							    inside_vrf_id,
-							    FIB_SOURCE_PLUGIN_HI);
+							    nat_fib_src_hi);
   sm->static_mapping_only = static_mapping_only;
   sm->static_mapping_connection_tracking = static_mapping_connection_tracking;
 
diff --git a/src/plugins/nat/nat.h b/src/plugins/nat/nat.h
index b65ad1b676f..ee712f4748f 100644
--- a/src/plugins/nat/nat.h
+++ b/src/plugins/nat/nat.h
@@ -23,6 +23,7 @@
 #include <vnet/ethernet/ethernet.h>
 #include <vnet/ip/icmp46_packet.h>
 #include <vnet/api_errno.h>
+#include <vnet/fib/fib_source.h>
 #include <vppinfra/elog.h>
 #include <vppinfra/bihash_8_8.h>
 #include <vppinfra/bihash_16_8.h>
@@ -742,6 +743,9 @@ extern vlib_node_registration_t nat44_ed_in2out_worker_handoff_node;
 extern vlib_node_registration_t nat44_ed_in2out_output_worker_handoff_node;
 extern vlib_node_registration_t nat44_ed_out2in_worker_handoff_node;
 
+extern fib_source_t nat_fib_src_hi;
+extern fib_source_t nat_fib_src_low;
+
 /* format functions */
 format_function_t format_snat_user;
 format_function_t format_snat_static_mapping;
diff --git a/src/plugins/nat/nat64.c b/src/plugins/nat/nat64.c
index 0fe29800420..e1afea6510e 100644
--- a/src/plugins/nat/nat64.c
+++ b/src/plugins/nat/nat64.c
@@ -343,7 +343,7 @@ nat64_add_del_pool_addr (u32 thread_index,
       if (vrf_id != ~0)
 	a->fib_index =
 	  fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP6, vrf_id,
-					     FIB_SOURCE_PLUGIN_HI);
+					     nat_fib_src_hi);
 #define _(N, id, n, s) \
       clib_bitmap_alloc (a->busy_##n##_port_bitmap, 65535); \
       a->busy_##n##_ports = 0; \
@@ -357,8 +357,7 @@ nat64_add_del_pool_addr (u32 thread_index,
 	return VNET_API_ERROR_NO_SUCH_ENTRY;
 
       if (a->fib_index != ~0)
-	fib_table_unlock (a->fib_index, FIB_PROTOCOL_IP6,
-			  FIB_SOURCE_PLUGIN_HI);
+	fib_table_unlock (a->fib_index, FIB_PROTOCOL_IP6, nat_fib_src_hi);
       /* Delete sessions using address */
         /* *INDENT-OFF* */
         vec_foreach (db, nm->db)
@@ -688,7 +687,7 @@ nat64_add_del_static_bib_entry (ip6_address_t * in_addr,
   nat64_main_t *nm = &nat64_main;
   nat64_db_bib_entry_t *bibe;
   u32 fib_index = fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP6, vrf_id,
-						     FIB_SOURCE_PLUGIN_HI);
+						     nat_fib_src_hi);
   snat_protocol_t p = ip_proto_to_snat_proto (proto);
   ip46_address_t addr;
   int i;
@@ -1027,7 +1026,7 @@ nat64_add_del_prefix (ip6_address_t * prefix, u8 plen, u32 vrf_id, u8 is_add)
 	  vec_add2 (nm->pref64, p, 1);
 	  p->fib_index =
 	    fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP6, vrf_id,
-					       FIB_SOURCE_PLUGIN_HI);
+					       nat_fib_src_hi);
 	  p->vrf_id = vrf_id;
 	}
 
diff --git a/src/plugins/nat/nat64_cli.c b/src/plugins/nat/nat64_cli.c
index 53152f11996..be468df1753 100644
--- a/src/plugins/nat/nat64_cli.c
+++ b/src/plugins/nat/nat64_cli.c
@@ -633,9 +633,9 @@ nat64_add_del_prefix_command_fn (vlib_main_t * vm, unformat_input_t * input,
 	{
 	  fib_index =
 	    fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP6,
-					       vrf_id, FIB_SOURCE_PLUGIN_HI);
+					       vrf_id, nat_fib_src_hi);
 	  fib_table_entry_update_one_path (fib_index, &fibpfx,
-					   FIB_SOURCE_PLUGIN_HI,
+					   nat_fib_src_hi,
 					   FIB_ENTRY_FLAG_NONE,
 					   DPO_PROTO_IP6, NULL,
 					   sw_if_index, ~0, 0,
@@ -645,12 +645,11 @@ nat64_add_del_prefix_command_fn (vlib_main_t * vm, unformat_input_t * input,
 	{
 	  fib_index = fib_table_find (FIB_PROTOCOL_IP6, vrf_id);
 	  fib_table_entry_path_remove (fib_index, &fibpfx,
-				       FIB_SOURCE_PLUGIN_HI,
+				       nat_fib_src_hi,
 				       DPO_PROTO_IP6, NULL,
 				       sw_if_index, ~0, 1,
 				       FIB_ROUTE_PATH_INTF_RX);
-	  fib_table_unlock (fib_index, FIB_PROTOCOL_IP6,
-			    FIB_SOURCE_PLUGIN_HI);
+	  fib_table_unlock (fib_index, FIB_PROTOCOL_IP6, nat_fib_src_hi);
 	}
     }
 
diff --git a/src/plugins/nat/nat66.c b/src/plugins/nat/nat66.c
index 2caefab6480..e5e783b31f7 100644
--- a/src/plugins/nat/nat66.c
+++ b/src/plugins/nat/nat66.c
@@ -170,7 +170,7 @@ nat66_static_mapping_add_del (ip6_address_t * l_addr, ip6_address_t * e_addr,
 	return VNET_API_ERROR_VALUE_EXIST;
 
       fib_index = fib_table_find_or_create_and_lock (FIB_PROTOCOL_IP6, vrf_id,
-						     FIB_SOURCE_PLUGIN_HI);
+						     nat_fib_src_hi);
       pool_get (nm->sm, sm);
       clib_memset (sm, 0, sizeof (*sm));
       sm->l_addr.as_u64[0] = l_addr->as_u64[0];
@@ -214,8 +214,7 @@ nat66_static_mapping_add_del (ip6_address_t * l_addr, ip6_address_t * e_addr,
       kv.key[2] = sm_key.as_u64[2];
       if (clib_bihash_add_del_24_8 (&nm->sm_e, &kv, 0))
 	nat_elog_warn ("nat66-static-map-by-external delete key failed");
-      fib_table_unlock (sm->fib_index, FIB_PROTOCOL_IP6,
-			FIB_SOURCE_PLUGIN_HI);
+      fib_table_unlock (sm->fib_index, FIB_PROTOCOL_IP6, nat_fib_src_hi);
       pool_put (nm->sm, sm);
     }
 
diff --git a/src/plugins/pppoe/pppoe.c b/src/plugins/pppoe/pppoe.c
index 2d63b3e8674..1f8a7288aeb 100644
--- a/src/plugins/pppoe/pppoe.c
+++ b/src/plugins/pppoe/pppoe.c
@@ -37,6 +37,8 @@
 
 pppoe_main_t pppoe_main;
 
+static fib_source_t pppoe_fib_src;
+
 u8 *
 format_pppoe_session (u8 * s, va_list * args)
 {
@@ -376,7 +378,7 @@ int vnet_pppoe_add_del_session
 
       /* add reverse route for client ip */
       fib_table_entry_path_add (a->decap_fib_index, &pfx,
-				FIB_SOURCE_PLUGIN_HI, FIB_ENTRY_FLAG_NONE,
+				pppoe_fib_src, FIB_ENTRY_FLAG_NONE,
 				fib_proto_to_dpo (pfx.fp_proto),
 				&pfx.fp_addr, sw_if_index, ~0,
 				1, NULL, FIB_ROUTE_PATH_FLAG_NONE);
@@ -408,7 +410,7 @@ int vnet_pppoe_add_del_session
 
       /* delete reverse route for client ip */
       fib_table_entry_path_remove (a->decap_fib_index, &pfx,
-				   FIB_SOURCE_PLUGIN_HI,
+				   pppoe_fib_src,
 				   fib_proto_to_dpo (pfx.fp_proto),
 				   &pfx.fp_addr,
 				   sw_if_index, ~0, 1,
@@ -721,6 +723,10 @@ pppoe_init (vlib_main_t * vm)
   ethernet_register_input_type (vm, ETHERNET_TYPE_PPPOE_DISCOVERY,
 				pppoe_cp_dispatch_node.index);
 
+  pppoe_fib_src = fib_source_allocate ("pppoe",
+				       FIB_SOURCE_PRIORITY_HI,
+				       FIB_SOURCE_BH_API);
+
   return 0;
 }
 
diff --git a/src/plugins/svs/svs.c b/src/plugins/svs/svs.c
index 8c1487c6ebc..555283397ff 100644
--- a/src/plugins/svs/svs.c
+++ b/src/plugins/svs/svs.c
@@ -26,10 +26,12 @@
 
 u32 *svs_itf_db[FIB_PROTOCOL_IP_MAX];
 
+static fib_source_t svs_fib_src;
+
 int
 svs_table_add (fib_protocol_t fproto, u32 table_id)
 {
-  fib_table_find_or_create_and_lock (fproto, table_id, FIB_SOURCE_PLUGIN_LOW);
+  fib_table_find_or_create_and_lock (fproto, table_id, svs_fib_src);
 
   return (0);
 }
@@ -50,7 +52,7 @@ svs_table_delete (fib_protocol_t fproto, u32 table_id)
   if (~0 == fib_index)
     return VNET_API_ERROR_NO_SUCH_FIB;
 
-  fib_table_unlock (fib_index, fproto, FIB_SOURCE_PLUGIN_LOW);
+  fib_table_unlock (fib_index, fproto, svs_fib_src);
 
   return (0);
 }
@@ -68,7 +70,7 @@ svs_route_add_i (u32 fib_index, const fib_prefix_t * pfx, u32 src_fib_index)
 				      LOOKUP_TABLE_FROM_CONFIG, &dpo);
 
   fib_table_entry_special_dpo_add (fib_index, pfx,
-				   FIB_SOURCE_PLUGIN_LOW,
+				   svs_fib_src,
 				   FIB_ENTRY_FLAG_EXCLUSIVE, &dpo);
 
   dpo_unlock (&dpo);
@@ -107,7 +109,7 @@ svs_route_delete (u32 table_id, const fib_prefix_t * pfx)
   if (~0 == fib_index)
     return VNET_API_ERROR_NO_SUCH_FIB;
 
-  fib_table_entry_special_remove (fib_index, pfx, FIB_SOURCE_PLUGIN_LOW);
+  fib_table_entry_special_remove (fib_index, pfx, svs_fib_src);
 
   return (0);
 }
@@ -214,7 +216,7 @@ svs_disable (fib_protocol_t fproto, u32 table_id, u32 sw_if_index)
 				"svs-ip4" :
 				"svs-ip6"), sw_if_index, 0, NULL, 0);
 
-  fib_table_entry_special_remove (fib_index, &pfx, FIB_SOURCE_PLUGIN_LOW);
+  fib_table_entry_special_remove (fib_index, &pfx, svs_fib_src);
 
   return (0);
 }
@@ -607,6 +609,10 @@ svs_init (vlib_main_t * vm)
   };
   vec_add1 (ip4_main.table_bind_callbacks, cbt4);
 
+  svs_fib_src = fib_source_allocate ("svs",
+				     FIB_SOURCE_PRIORITY_LOW,
+				     FIB_SOURCE_BH_SIMPLE);
+
   return (NULL);
 }
 
diff --git a/src/plugins/unittest/fib_test.c b/src/plugins/unittest/fib_test.c
index f220eb0d358..2d75f28a8ca 100644
--- a/src/plugins/unittest/fib_test.c
+++ b/src/plugins/unittest/fib_test.c
@@ -9310,13 +9310,16 @@ fib_test_inherit (void)
              "%U via 10.10.10.2",
              format_fib_prefix, &pfx_10_10_10_0_s_24);
 
+    fib_source_t hi_src = fib_source_allocate("test", 0x50,
+                                              FIB_SOURCE_BH_SIMPLE);
+
     /*
      * add the source that replaces inherited state.
      * inheriting source is not the best, so it doesn't push state.
      */
     fib_table_entry_update_one_path(0,
                                     &pfx_10_10_10_0_s_24,
-                                    FIB_SOURCE_PLUGIN_HI,
+                                    hi_src,
                                     FIB_ENTRY_FLAG_NONE,
                                     DPO_PROTO_IP4,
                                     &nh_10_10_10_1,
@@ -9354,7 +9357,7 @@ fib_test_inherit (void)
      * withdraw the higher priority source and expect the inherited to return
      * throughout the sub-tree
      */
-    fib_table_entry_delete(0, &pfx_10_10_10_0_s_24, FIB_SOURCE_PLUGIN_HI);
+    fib_table_entry_delete(0, &pfx_10_10_10_0_s_24, hi_src);
 
     fei = fib_table_lookup_exact_match(0, &pfx_10_10_10_21_s_32);
     FIB_TEST(!fib_test_validate_entry(fei,