session: use session error type instead of vnet error

Type: improvement

Change-Id: Ie0bad9e03ac2e29da23af01ee7f63cb44489ad9c
Signed-off-by: Filip Tehlar <ftehlar@cisco.com>

13 files changed, 116 insertions, 91 deletions

diff --git a/src/vnet/session/application.c b/src/vnet/session/application.c
index 59989214231..cf867401ea2 100644
--- a/src/vnet/session/application.c
+++ b/src/vnet/session/application.c
@@ -765,8 +765,8 @@ application_verify_cfg (ssvm_segment_type_t st)
     return 1;
 }
 
-static int
-application_alloc_and_init (app_init_args_t * a)
+static session_error_t
+application_alloc_and_init (app_init_args_t *a)
 {
   ssvm_segment_type_t seg_type = SSVM_SEGMENT_MEMFD;
   segment_manager_props_t *props;
@@ -787,15 +787,15 @@ application_alloc_and_init (app_init_args_t * a)
     {
       clib_warning ("mq eventfds can only be used if socket transport is "
 		    "used for binary api");
-      return VNET_API_ERROR_APP_UNSUPPORTED_CFG;
+      return SESSION_E_NOSUPPORT;
     }
 
   if (!application_verify_cfg (seg_type))
-    return VNET_API_ERROR_APP_UNSUPPORTED_CFG;
+    return SESSION_E_NOSUPPORT;
 
   if (opts[APP_OPTIONS_PREALLOC_FIFO_PAIRS] &&
       opts[APP_OPTIONS_PREALLOC_FIFO_HDRS])
-    return VNET_API_ERROR_APP_UNSUPPORTED_CFG;
+    return SESSION_E_NOSUPPORT;
 
   /* Check that the obvious things are properly set up */
   application_verify_cb_fns (a->session_cb_vft);
@@ -1048,8 +1048,8 @@ application_alloc_worker_and_init (application_t * app, app_worker_t ** wrk)
   return 0;
 }
 
-int
-vnet_app_worker_add_del (vnet_app_worker_add_del_args_t * a)
+session_error_t
+vnet_app_worker_add_del (vnet_app_worker_add_del_args_t *a)
 {
   fifo_segment_t *fs;
   app_worker_map_t *wrk_map;
@@ -1060,7 +1060,7 @@ vnet_app_worker_add_del (vnet_app_worker_add_del_args_t * a)
 
   app = application_get (a->app_index);
   if (!app)
-    return VNET_API_ERROR_INVALID_VALUE;
+    return SESSION_E_INVALID;
 
   if (a->is_add)
     {
@@ -1083,11 +1083,11 @@ vnet_app_worker_add_del (vnet_app_worker_add_del_args_t * a)
     {
       wrk_map = app_worker_map_get (app, a->wrk_map_index);
       if (!wrk_map)
-	return VNET_API_ERROR_INVALID_VALUE;
+	return SESSION_E_INVALID;
 
       app_wrk = app_worker_get (wrk_map->wrk_index);
       if (!app_wrk)
-	return VNET_API_ERROR_INVALID_VALUE;
+	return SESSION_E_INVALID;
 
       application_api_table_del (app_wrk->api_client_index);
       if (appns_sapi_enabled ())
@@ -1100,8 +1100,8 @@ vnet_app_worker_add_del (vnet_app_worker_add_del_args_t * a)
   return 0;
 }
 
-static int
-app_validate_namespace (u8 * namespace_id, u64 secret, u32 * app_ns_index)
+static session_error_t
+app_validate_namespace (u8 *namespace_id, u64 secret, u32 *app_ns_index)
 {
   app_namespace_t *app_ns;
   if (vec_len (namespace_id) == 0)
@@ -1113,12 +1113,12 @@ app_validate_namespace (u8 * namespace_id, u64 secret, u32 * app_ns_index)
 
   *app_ns_index = app_namespace_index_from_id (namespace_id);
   if (*app_ns_index == APP_NAMESPACE_INVALID_INDEX)
-    return VNET_API_ERROR_APP_INVALID_NS;
+    return SESSION_E_INVALID_NS;
   app_ns = app_namespace_get (*app_ns_index);
   if (!app_ns)
-    return VNET_API_ERROR_APP_INVALID_NS;
+    return SESSION_E_INVALID_NS;
   if (app_ns->ns_secret != secret)
-    return VNET_API_ERROR_APP_WRONG_NS_SECRET;
+    return SESSION_E_WRONG_NS_SECRET;
   return 0;
 }
 
@@ -1142,8 +1142,8 @@ app_name_from_api_index (u32 api_client_index)
  * to external app and a segment manager for shared memory fifo based
  * communication with the external app.
  */
-int
-vnet_application_attach (vnet_app_attach_args_t * a)
+session_error_t
+vnet_application_attach (vnet_app_attach_args_t *a)
 {
   fifo_segment_t *fs;
   application_t *app = 0;
@@ -1152,17 +1152,17 @@ vnet_application_attach (vnet_app_attach_args_t * a)
   u32 app_ns_index = 0;
   u8 *app_name = 0;
   u64 secret;
-  int rv;
+  session_error_t rv;
 
   if (a->api_client_index != APP_INVALID_INDEX)
     app = application_lookup (a->api_client_index);
   else if (a->name)
     app = application_lookup_name (a->name);
   else
-    return VNET_API_ERROR_INVALID_VALUE;
+    return SESSION_E_INVALID;
 
   if (app)
-    return VNET_API_ERROR_APP_ALREADY_ATTACHED;
+    return SESSION_E_APP_ATTACHED;
 
   /* Socket api sets the name and validates namespace prior to attach */
   if (!a->use_sock_api)
@@ -1216,8 +1216,8 @@ vnet_application_attach (vnet_app_attach_args_t * a)
 /**
  * Detach application from vpp
  */
-int
-vnet_application_detach (vnet_app_detach_args_t * a)
+session_error_t
+vnet_application_detach (vnet_app_detach_args_t *a)
 {
   application_t *app;
 
@@ -1225,7 +1225,7 @@ vnet_application_detach (vnet_app_detach_args_t * a)
   if (!app)
     {
       clib_warning ("app not attached");
-      return VNET_API_ERROR_APPLICATION_NOT_ATTACHED;
+      return SESSION_E_NOAPP;
     }
 
   app_interface_check_thread_and_barrier (vnet_application_detach, a);
@@ -1299,8 +1299,8 @@ session_endpoint_update_for_app (session_endpoint_cfg_t * sep,
     }
 }
 
-int
-vnet_listen (vnet_listen_args_t * a)
+session_error_t
+vnet_listen (vnet_listen_args_t *a)
 {
   app_listener_t *app_listener;
   app_worker_t *app_wrk;
@@ -1353,8 +1353,8 @@ vnet_listen (vnet_listen_args_t * a)
   return 0;
 }
 
-int
-vnet_connect (vnet_connect_args_t * a)
+session_error_t
+vnet_connect (vnet_connect_args_t *a)
 {
   app_worker_t *client_wrk;
   application_t *client;
@@ -1377,7 +1377,7 @@ vnet_connect (vnet_connect_args_t * a)
    */
   if (application_has_local_scope (client))
     {
-      int rv;
+      session_error_t rv;
 
       a->sep_ext.original_tp = a->sep_ext.transport_proto;
       a->sep_ext.transport_proto = TRANSPORT_PROTO_NONE;
@@ -1392,8 +1392,8 @@ vnet_connect (vnet_connect_args_t * a)
   return app_worker_connect_session (client_wrk, &a->sep_ext, &a->sh);
 }
 
-int
-vnet_unlisten (vnet_unlisten_args_t * a)
+session_error_t
+vnet_unlisten (vnet_unlisten_args_t *a)
 {
   app_worker_t *app_wrk;
   app_listener_t *al;
@@ -1423,7 +1423,7 @@ vnet_unlisten (vnet_unlisten_args_t * a)
   return app_worker_stop_listen (app_wrk, al);
 }
 
-int
+session_error_t
 vnet_shutdown_session (vnet_shutdown_args_t *a)
 {
   app_worker_t *app_wrk;
@@ -1444,8 +1444,8 @@ vnet_shutdown_session (vnet_shutdown_args_t *a)
   return 0;
 }
 
-int
-vnet_disconnect_session (vnet_disconnect_args_t * a)
+session_error_t
+vnet_disconnect_session (vnet_disconnect_args_t *a)
 {
   app_worker_t *app_wrk;
   session_t *s;
@@ -2082,7 +2082,7 @@ vnet_app_del_cert_key_pair (u32 index)
   u32 *app_index;
 
   if (!(ckpair = app_cert_key_pair_get_if_valid (index)))
-    return (VNET_API_ERROR_INVALID_VALUE);
+    return SESSION_E_INVALID;
 
   vec_foreach (app_index, ckpair->app_interests)
   {
diff --git a/src/vnet/session/application.h b/src/vnet/session/application.h
index e100fe89e63..c3d6180022f 100644
--- a/src/vnet/session/application.h
+++ b/src/vnet/session/application.h
@@ -327,7 +327,8 @@ int app_worker_own_session (app_worker_t * app_wrk, session_t * s);
 void app_worker_free (app_worker_t * app_wrk);
 int app_worker_connect_session (app_worker_t *app, session_endpoint_cfg_t *sep,
 				session_handle_t *rsh);
-int app_worker_start_listen (app_worker_t * app_wrk, app_listener_t * lstnr);
+session_error_t app_worker_start_listen (app_worker_t *app_wrk,
+					 app_listener_t *lstnr);
 int app_worker_stop_listen (app_worker_t * app_wrk, app_listener_t * al);
 int app_worker_init_accepted (session_t * s);
 int app_worker_accept_notify (app_worker_t * app_wrk, session_t * s);
@@ -374,7 +375,7 @@ u8 *format_app_worker_listener (u8 * s, va_list * args);
 u8 *format_crypto_engine (u8 * s, va_list * args);
 u8 *format_crypto_context (u8 * s, va_list * args);
 void app_worker_format_connects (app_worker_t * app_wrk, int verbose);
-int vnet_app_worker_add_del (vnet_app_worker_add_del_args_t * a);
+session_error_t vnet_app_worker_add_del (vnet_app_worker_add_del_args_t *a);
 
 uword unformat_application_proto (unformat_input_t * input, va_list * args);
 
diff --git a/src/vnet/session/application_interface.c b/src/vnet/session/application_interface.c
index 74f456a1eab..86f3dcdece6 100644
--- a/src/vnet/session/application_interface.c
+++ b/src/vnet/session/application_interface.c
@@ -73,8 +73,8 @@ unformat_vnet_uri (unformat_input_t * input, va_list * args)
 static u8 *cache_uri;
 static session_endpoint_cfg_t *cache_sep;
 
-int
-parse_uri (char *uri, session_endpoint_cfg_t * sep)
+session_error_t
+parse_uri (char *uri, session_endpoint_cfg_t *sep)
 {
   unformat_input_t _input, *input = &_input;
 
@@ -92,7 +92,7 @@ parse_uri (char *uri, session_endpoint_cfg_t * sep)
   if (!unformat (input, "%U", unformat_vnet_uri, sep))
     {
       unformat_free (input);
-      return VNET_API_ERROR_INVALID_VALUE;
+      return SESSION_E_INVALID;
     }
   unformat_free (input);
 
@@ -120,36 +120,36 @@ vnet_bind_uri (vnet_listen_args_t * a)
   return vnet_listen (a);
 }
 
-int
-vnet_unbind_uri (vnet_unlisten_args_t * a)
+session_error_t
+vnet_unbind_uri (vnet_unlisten_args_t *a)
 {
   session_endpoint_cfg_t sep = SESSION_ENDPOINT_CFG_NULL;
   application_t *app;
   session_t *listener;
   u32 table_index;
-  int rv;
+  session_error_t rv;
 
   if ((rv = parse_uri (a->uri, &sep)))
     return rv;
 
   app = application_get (a->app_index);
   if (!app)
-    return VNET_API_ERROR_INVALID_VALUE;
+    return SESSION_E_INVALID;
 
   table_index = application_session_table (app, fib_ip_proto (!sep.is_ip4));
   listener = session_lookup_listener (table_index,
 				      (session_endpoint_t *) & sep);
   if (!listener)
-    return VNET_API_ERROR_ADDRESS_NOT_IN_USE;
+    return SESSION_E_ADDR_NOT_IN_USE;
   a->handle = listen_session_get_handle (listener);
   return vnet_unlisten (a);
 }
 
-int
-vnet_connect_uri (vnet_connect_args_t * a)
+session_error_t
+vnet_connect_uri (vnet_connect_args_t *a)
 {
   session_endpoint_cfg_t sep = SESSION_ENDPOINT_CFG_NULL;
-  int rv;
+  session_error_t rv;
 
   if ((rv = parse_uri (a->uri, &sep)))
     return rv;
diff --git a/src/vnet/session/application_interface.h b/src/vnet/session/application_interface.h
index 510068b7769..d76b9f7fd8b 100644
--- a/src/vnet/session/application_interface.h
+++ b/src/vnet/session/application_interface.h
@@ -271,18 +271,18 @@ typedef enum session_fd_flag_
 #undef _
 } session_fd_flag_t;
 
-int parse_uri (char *uri, session_endpoint_cfg_t * sep);
-int vnet_bind_uri (vnet_listen_args_t *);
-int vnet_unbind_uri (vnet_unlisten_args_t * a);
-int vnet_connect_uri (vnet_connect_args_t * a);
-
-int vnet_application_attach (vnet_app_attach_args_t * a);
-int vnet_application_detach (vnet_app_detach_args_t * a);
-int vnet_listen (vnet_listen_args_t * a);
-int vnet_connect (vnet_connect_args_t * a);
-int vnet_unlisten (vnet_unlisten_args_t * a);
-int vnet_shutdown_session (vnet_shutdown_args_t *a);
-int vnet_disconnect_session (vnet_disconnect_args_t * a);
+session_error_t parse_uri (char *uri, session_endpoint_cfg_t *sep);
+session_error_t vnet_bind_uri (vnet_listen_args_t *);
+session_error_t vnet_unbind_uri (vnet_unlisten_args_t *a);
+session_error_t vnet_connect_uri (vnet_connect_args_t *a);
+
+session_error_t vnet_application_attach (vnet_app_attach_args_t *a);
+session_error_t vnet_application_detach (vnet_app_detach_args_t *a);
+session_error_t vnet_listen (vnet_listen_args_t *a);
+session_error_t vnet_connect (vnet_connect_args_t *a);
+session_error_t vnet_unlisten (vnet_unlisten_args_t *a);
+session_error_t vnet_shutdown_session (vnet_shutdown_args_t *a);
+session_error_t vnet_disconnect_session (vnet_disconnect_args_t *a);
 
 int vnet_app_add_cert_key_pair (vnet_app_add_cert_key_pair_args_t * a);
 int vnet_app_del_cert_key_pair (u32 index);
diff --git a/src/vnet/session/application_namespace.c b/src/vnet/session/application_namespace.c
index 13b540cd3b8..03e41fdb22d 100644
--- a/src/vnet/session/application_namespace.c
+++ b/src/vnet/session/application_namespace.c
@@ -81,21 +81,20 @@ app_namespace_alloc (const u8 *ns_id)
   return app_ns;
 }
 
-int
-vnet_app_namespace_add_del (vnet_app_namespace_add_del_args_t * a)
+session_error_t
+vnet_app_namespace_add_del (vnet_app_namespace_add_del_args_t *a)
 {
   app_namespace_t *app_ns;
   session_table_t *st;
   u32 ns_index;
-  int rv;
+  session_error_t rv;
 
   if (a->is_add)
     {
       if (a->sw_if_index != APP_NAMESPACE_INVALID_INDEX
 	  && !vnet_get_sw_interface_or_null (vnet_get_main (),
 					     a->sw_if_index))
-	return VNET_API_ERROR_INVALID_SW_IF_INDEX;
-
+	return SESSION_E_INVALID;
 
       if (a->sw_if_index != APP_NAMESPACE_INVALID_INDEX)
 	{
@@ -108,7 +107,7 @@ vnet_app_namespace_add_del (vnet_app_namespace_add_del_args_t * a)
 	}
       if (a->sw_if_index == APP_NAMESPACE_INVALID_INDEX
 	  && a->ip4_fib_id == APP_NAMESPACE_INVALID_INDEX)
-	return VNET_API_ERROR_INVALID_VALUE;
+	return SESSION_E_INVALID;
 
       app_ns = app_namespace_get_from_id (a->ns_id);
       if (!app_ns)
@@ -148,11 +147,11 @@ vnet_app_namespace_add_del (vnet_app_namespace_add_del_args_t * a)
     {
       ns_index = app_namespace_index_from_id (a->ns_id);
       if (ns_index == APP_NAMESPACE_INVALID_INDEX)
-	return VNET_API_ERROR_INVALID_VALUE;
+	return SESSION_E_INVALID;
 
       app_ns = app_namespace_get (ns_index);
       if (!app_ns)
-	return VNET_API_ERROR_INVALID_VALUE;
+	return SESSION_E_INVALID;
 
       application_namespace_cleanup (app_ns);
 
diff --git a/src/vnet/session/application_namespace.h b/src/vnet/session/application_namespace.h
index 02a4a0780d4..261325cbe0e 100644
--- a/src/vnet/session/application_namespace.h
+++ b/src/vnet/session/application_namespace.h
@@ -82,7 +82,8 @@ const u8 *app_namespace_id (app_namespace_t * app_ns);
 const u8 *app_namespace_id_from_index (u32 index);
 u32 app_namespace_index_from_id (const u8 *ns_id);
 void app_namespaces_init (void);
-int vnet_app_namespace_add_del (vnet_app_namespace_add_del_args_t * a);
+session_error_t
+vnet_app_namespace_add_del (vnet_app_namespace_add_del_args_t *a);
 u32 app_namespace_get_fib_index (app_namespace_t * app_ns, u8 fib_proto);
 session_table_t *app_namespace_get_local_table (app_namespace_t * app_ns);
 
diff --git a/src/vnet/session/application_worker.c b/src/vnet/session/application_worker.c
index 1927f2f78d3..c3941d1fd7b 100644
--- a/src/vnet/session/application_worker.c
+++ b/src/vnet/session/application_worker.c
@@ -202,9 +202,8 @@ app_worker_init_listener (app_worker_t * app_wrk, session_t * ls)
   return 0;
 }
 
-int
-app_worker_start_listen (app_worker_t * app_wrk,
-			 app_listener_t * app_listener)
+session_error_t
+app_worker_start_listen (app_worker_t *app_wrk, app_listener_t *app_listener)
 {
   session_t *ls;
   int rv;
diff --git a/src/vnet/session/session_api.c b/src/vnet/session/session_api.c
index 3d70733ceb2..ff11bcb690a 100644
--- a/src/vnet/session/session_api.c
+++ b/src/vnet/session/session_api.c
@@ -534,7 +534,8 @@ vl_api_app_attach_t_handler (vl_api_app_attach_t * mp)
 
   if ((rv = vnet_application_attach (a)))
     {
-      clib_warning ("attach returned: %d", rv);
+      clib_warning ("attach returned: %U", format_session_error, rv);
+      rv = VNET_API_ERROR_UNSPECIFIED;
       vec_free (a->namespace_id);
       goto done;
     }
@@ -641,7 +642,9 @@ vl_api_app_worker_add_del_t_handler (vl_api_app_worker_add_del_t * mp)
   rv = vnet_app_worker_add_del (&args);
   if (rv)
     {
-      clib_warning ("app worker add/del returned: %d", rv);
+      clib_warning ("app worker add/del returned: %U", format_session_error,
+		    rv);
+      rv = VNET_API_ERROR_UNSPECIFIED;
       goto done;
     }
 
@@ -709,6 +712,12 @@ vl_api_application_detach_t_handler (vl_api_application_detach_t * mp)
       a->app_index = app->app_index;
       a->api_client_index = mp->client_index;
       rv = vnet_application_detach (a);
+      if (rv)
+	{
+	  clib_warning ("vnet_application_detach: %U", format_session_error,
+			rv);
+	  rv = VNET_API_ERROR_UNSPECIFIED;
+	}
     }
 
 done:
@@ -934,7 +943,10 @@ vl_api_session_rule_add_del_t_handler (vl_api_session_rule_add_del_t * mp)
 
   rv = vnet_session_rule_add_del (&args);
   if (rv)
-    clib_warning ("rule add del returned: %d", rv);
+    {
+      clib_warning ("rule add del returned: %U", format_session_error, rv);
+      rv = VNET_API_ERROR_UNSPECIFIED;
+    }
   vec_free (table_args->tag);
   REPLY_MACRO (VL_API_SESSION_RULE_ADD_DEL_REPLY);
 }
@@ -1149,6 +1161,12 @@ vl_api_app_del_cert_key_pair_t_handler (vl_api_app_del_cert_key_pair_t * mp)
     }
   ckpair_index = clib_net_to_host_u32 (mp->index);
   rv = vnet_app_del_cert_key_pair (ckpair_index);
+  if (rv)
+    {
+      clib_warning ("vnet_app_del_cert_key_pair: %U", format_session_error,
+		    rv);
+      rv = VNET_API_ERROR_UNSPECIFIED;
+    }
 
 done:
   REPLY_MACRO (VL_API_APP_DEL_CERT_KEY_PAIR_REPLY);
@@ -1367,7 +1385,7 @@ sapi_add_del_worker_handler (app_namespace_t * app_ns,
   app = application_get_if_valid (mp->app_index);
   if (!app)
     {
-      rv = VNET_API_ERROR_INVALID_VALUE;
+      rv = SESSION_E_INVALID;
       goto done;
     }
 
@@ -1382,7 +1400,8 @@ sapi_add_del_worker_handler (app_namespace_t * app_ns,
   rv = vnet_app_worker_add_del (&args);
   if (rv)
     {
-      clib_warning ("app worker add/del returned: %d", rv);
+      clib_warning ("app worker add/del returned: %U", format_session_error,
+		    rv);
       goto done;
     }
 
@@ -1730,7 +1749,7 @@ appns_sapi_add_ns_socket (app_namespace_t * app_ns)
       if (err)
 	{
 	  clib_error_report (err);
-	  return VNET_API_ERROR_SYSCALL_ERROR_1;
+	  return SESSION_E_SYSCALL;
 	}
     }
 
diff --git a/src/vnet/session/session_lookup.c b/src/vnet/session/session_lookup.c
index 68f98d0f046..a8845996a08 100644
--- a/src/vnet/session/session_lookup.c
+++ b/src/vnet/session/session_lookup.c
@@ -1311,8 +1311,8 @@ session_lookup_connection (u32 fib_index, ip46_address_t * lcl,
 				       lcl_port, rmt_port, proto);
 }
 
-int
-vnet_session_rule_add_del (session_rule_add_del_args_t * args)
+session_error_t
+vnet_session_rule_add_del (session_rule_add_del_args_t *args)
 {
   app_namespace_t *app_ns = app_namespace_get (args->appns_index);
   session_rules_table_t *srt;
@@ -1322,14 +1322,14 @@ vnet_session_rule_add_del (session_rule_add_del_args_t * args)
   int rv = 0;
 
   if (!app_ns)
-    return VNET_API_ERROR_APP_INVALID_NS;
+    return SESSION_E_INVALID_NS;
 
   if (args->scope > 3)
-    return VNET_API_ERROR_INVALID_VALUE;
+    return SESSION_E_INVALID;
 
   if (args->transport_proto != TRANSPORT_PROTO_TCP
       && args->transport_proto != TRANSPORT_PROTO_UDP)
-    return VNET_API_ERROR_INVALID_VALUE;
+    return SESSION_E_INVALID;
 
   if ((args->scope & SESSION_RULE_SCOPE_GLOBAL) || args->scope == 0)
     {
diff --git a/src/vnet/session/session_lookup.h b/src/vnet/session/session_lookup.h
index c1037dff8c9..86148d1830a 100644
--- a/src/vnet/session/session_lookup.h
+++ b/src/vnet/session/session_lookup.h
@@ -130,7 +130,7 @@ typedef struct _session_rule_add_del_args
   u8 transport_proto;
 } session_rule_add_del_args_t;
 
-int vnet_session_rule_add_del (session_rule_add_del_args_t * args);
+session_error_t vnet_session_rule_add_del (session_rule_add_del_args_t *args);
 void session_lookup_set_tables_appns (app_namespace_t * app_ns);
 
 void session_lookup_init (void);
diff --git a/src/vnet/session/session_rules_table.c b/src/vnet/session/session_rules_table.c
index 5108c00d728..9b90c2cd9ff 100644
--- a/src/vnet/session/session_rules_table.c
+++ b/src/vnet/session/session_rules_table.c
@@ -386,11 +386,11 @@ session_rules_table_lookup6 (session_rules_table_t * srt,
  * @param srt table where rule should be added
  * @param args rule arguments
  *
- * @return 0 if success, clib_error_t error otherwise
+ * @return 0 if success, session_error_t error otherwise
  */
-int
-session_rules_table_add_del (session_rules_table_t * srt,
-			     session_rule_table_add_del_args_t * args)
+session_error_t
+session_rules_table_add_del (session_rules_table_t *srt,
+			     session_rule_table_add_del_args_t *args)
 {
   u8 fib_proto = args->rmt.fp_proto, *rt;
   u32 ri_from_tag, ri;
@@ -398,7 +398,7 @@ session_rules_table_add_del (session_rules_table_t * srt,
 
   ri_from_tag = session_rules_table_rule_for_tag (srt, args->tag);
   if (args->is_add && ri_from_tag != SESSION_RULES_TABLE_INVALID_INDEX)
-    return VNET_API_ERROR_INVALID_VALUE;
+    return SESSION_E_INVALID;
 
   if (fib_proto == FIB_PROTOCOL_IP4)
     {
@@ -509,7 +509,7 @@ session_rules_table_add_del (session_rules_table_t * srt,
 	}
     }
   else
-    return VNET_API_ERROR_INVALID_VALUE_2;
+    return SESSION_E_INVALID;
   return 0;
 }
 
diff --git a/src/vnet/session/session_rules_table.h b/src/vnet/session/session_rules_table.h
index 206ef2f380f..d61f2c60ca9 100644
--- a/src/vnet/session/session_rules_table.h
+++ b/src/vnet/session/session_rules_table.h
@@ -18,6 +18,7 @@
 
 #include <vnet/vnet.h>
 #include <vnet/fib/fib.h>
+#include <vnet/session/session_types.h>
 #include <vnet/session/transport.h>
 #include <vnet/session/mma_16.h>
 #include <vnet/session/mma_40.h>
@@ -111,8 +112,9 @@ void session_rules_table_show_rule (vlib_main_t * vm,
 				    ip46_address_t * lcl_ip, u16 lcl_port,
 				    ip46_address_t * rmt_ip, u16 rmt_port,
 				    u8 is_ip4);
-int session_rules_table_add_del (session_rules_table_t * srt,
-				 session_rule_table_add_del_args_t * args);
+session_error_t
+session_rules_table_add_del (session_rules_table_t *srt,
+			     session_rule_table_add_del_args_t *args);
 u8 *session_rules_table_rule_tag (session_rules_table_t * srt, u32 ri,
 				  u8 is_ip4);
 void session_rules_table_init (session_rules_table_t * srt);
diff --git a/src/vnet/session/session_types.h b/src/vnet/session/session_types.h
index 9ad40fcca7f..8755a146bce 100644
--- a/src/vnet/session/session_types.h
+++ b/src/vnet/session/session_types.h
@@ -484,9 +484,11 @@ STATIC_ASSERT (sizeof (session_dgram_hdr_t) == (SESSION_CONN_ID_LEN + 10),
   _ (NOLISTEN, "not listening")                                               \
   _ (NOSESSION, "session does not exist")                                     \
   _ (NOAPP, "app not attached")                                               \
+  _ (APP_ATTACHED, "app already attached")                                    \
   _ (PORTINUSE, "lcl port in use")                                            \
   _ (IPINUSE, "ip in use")                                                    \
   _ (ALREADY_LISTENING, "ip port pair already listened on")                   \
+  _ (ADDR_NOT_IN_USE, "address not in use")                                   \
   _ (INVALID, "invalid value")                                                \
   _ (INVALID_RMT_IP, "invalid remote ip")                                     \
   _ (INVALID_APPWRK, "invalid app worker")                                    \
@@ -506,6 +508,8 @@ STATIC_ASSERT (sizeof (session_dgram_hdr_t) == (SESSION_CONN_ID_LEN + 10),
   _ (NOCRYPTOENG, "no crypto engine")                                         \
   _ (NOCRYPTOCKP, "cert key pair not found ")                                 \
   _ (LOCAL_CONNECT, "could not connect with local scope")                     \
+  _ (WRONG_NS_SECRET, "wrong ns secret")                                      \
+  _ (SYSCALL, "system call error")                                            \
   _ (TRANSPORT_NO_REG, "transport was not registered")
 
 typedef enum session_error_p_