l3cfg: add support for tracking routes that are currently unavailable

It doesn't yet do anything. More is needed. In particular, we need to
keep track of routes that were externally deleted, then we can merge
that with routes that are known to be currently unavailable.

2 files changed, 254 insertions, 6 deletions

diff --git a/src/nm-l3cfg.c b/src/nm-l3cfg.c
index 46b1c0f821..db4072f42d 100644
--- a/src/nm-l3cfg.c
+++ b/src/nm-l3cfg.c
@@ -25,11 +25,25 @@ NM_GOBJECT_PROPERTIES_DEFINE (NML3Cfg,
 	PROP_IFINDEX,
 );
 
+enum {
+	SIGNAL_NOTIFY,
+	LAST_SIGNAL,
+};
+
+static guint signals[LAST_SIGNAL] = { 0 };
+
+static GQuark signal_notify_quarks[_NM_L3_CONFIG_NOTIFY_TYPE_NUM];
+
 typedef struct _NML3CfgPrivate {
 	GArray *property_emit_list;
 	GArray *l3_config_datas;
 	const NML3ConfigData *combined_l3cfg;
+
+	GHashTable *routes_temporary_not_available_hash;
+
 	guint64 pseudo_timestamp_counter;
+
+	guint routes_temporary_not_available_id;
 } NML3CfgPrivate;
 
 struct _NML3CfgClass {
@@ -58,6 +72,23 @@ static void _property_emit_notify (NML3Cfg *self, NML3CfgPropertyEmitType emit_t
 /*****************************************************************************/
 
 static void
+_l3cfg_emit_signal_notify (NML3Cfg *self,
+                           NML3ConfigNotifyType notify_type,
+                           gpointer pay_load)
+{
+	nm_assert (_NM_INT_NOT_NEGATIVE (notify_type));
+	nm_assert (notify_type < G_N_ELEMENTS (signal_notify_quarks));
+
+	g_signal_emit (self,
+	               signals[SIGNAL_NOTIFY],
+	               signal_notify_quarks[notify_type],
+	               (int) notify_type,
+	               pay_load);
+}
+
+/*****************************************************************************/
+
+static void
 _load_link (NML3Cfg *self, gboolean initial)
 {
 	nm_auto_nmpobj const NMPObject *obj_old = NULL;
@@ -565,25 +596,209 @@ _l3cfg_update_combined_config (NML3Cfg *self,
 
 /*****************************************************************************/
 
+typedef struct {
+	const NMPObject *obj;
+	gint64 timestamp_msec;
+	bool dirty;
+} RoutesTemporaryNotAvailableData;
+
+static void
+_routes_temporary_not_available_data_free (gpointer user_data)
+{
+	RoutesTemporaryNotAvailableData *data = user_data;
+
+	nmp_object_unref (data->obj);
+	nm_g_slice_free (data);
+}
+
+#define ROUTES_TEMPORARY_NOT_AVAILABLE_MAX_AGE_MSEC ((gint64) 20000)
+
+static gboolean
+_routes_temporary_not_available_timeout (gpointer user_data)
+{
+	RoutesTemporaryNotAvailableData *data;
+	NML3Cfg *self = NM_L3CFG (user_data);
+	GHashTableIter iter;
+	gint64 expiry_threshold_msec;
+	gboolean any_expired = FALSE;
+	gint64 now_msec;
+	gint64 oldest_msec;
+
+	self->priv.p->routes_temporary_not_available_id = 0;
+
+	if (!self->priv.p->routes_temporary_not_available_hash)
+		return G_SOURCE_REMOVE;
+
+	/* we check the timeouts again. That is, because we allow to remove
+	 * entries from routes_temporary_not_available_hash, without rescheduling
+	 * out timeouts. */
+
+	now_msec = nm_utils_get_monotonic_timestamp_msec ();
+
+	expiry_threshold_msec = now_msec - ROUTES_TEMPORARY_NOT_AVAILABLE_MAX_AGE_MSEC;
+	oldest_msec = G_MAXINT64;
+
+	g_hash_table_iter_init (&iter, self->priv.p->routes_temporary_not_available_hash);
+	while (g_hash_table_iter_next (&iter, (gpointer *) &data, NULL)) {
+		if (data->timestamp_msec >= expiry_threshold_msec) {
+			any_expired = TRUE;
+			break;
+		}
+		if (data->timestamp_msec < oldest_msec)
+			oldest_msec = data->timestamp_msec;
+	}
+
+	if (any_expired) {
+		/* a route expired. We emit a signal, but we don't schedule it again. That will
+		 * only happen if the user calls nm_l3cfg_platform_commit() again. */
+		_l3cfg_emit_signal_notify (self, NM_L3_CONFIG_NOTIFY_TYPE_ROUTES_TEMPORARY_NOT_AVAILABLE_EXPIRED, NULL);
+		return G_SOURCE_REMOVE;
+	}
+
+	if (oldest_msec != G_MAXINT64) {
+		/* we have a timeout still. Reschedule. */
+		self->priv.p->routes_temporary_not_available_id = g_timeout_add (oldest_msec + ROUTES_TEMPORARY_NOT_AVAILABLE_MAX_AGE_MSEC - now_msec,
+		                                                                 _routes_temporary_not_available_timeout,
+		                                                                 self);
+	}
+	return G_SOURCE_REMOVE;
+}
+
+static gboolean
+_routes_temporary_not_available_update (NML3Cfg *self,
+                                        int addr_family,
+                                        GPtrArray *routes_temporary_not_available_arr)
+{
+
+	RoutesTemporaryNotAvailableData *data;
+	GHashTableIter iter;
+	gint64 oldest_msec;
+	gint64 now_msec;
+	gboolean prune_all = FALSE;
+	gboolean success = TRUE;
+	guint i;
+
+	now_msec = nm_utils_get_monotonic_timestamp_msec ();
+
+	if (nm_g_ptr_array_len (routes_temporary_not_available_arr) <= 0) {
+		prune_all = TRUE;
+		goto out_prune;
+	}
+
+	if (self->priv.p->routes_temporary_not_available_hash) {
+		g_hash_table_iter_init (&iter, self->priv.p->routes_temporary_not_available_hash);
+		while (g_hash_table_iter_next (&iter, (gpointer *) &data, NULL)) {
+			if (NMP_OBJECT_GET_ADDR_FAMILY (data->obj) == addr_family)
+				data->dirty = TRUE;
+		}
+	} else {
+		self->priv.p->routes_temporary_not_available_hash = g_hash_table_new_full (nmp_object_indirect_id_hash,
+		                                                                           nmp_object_indirect_id_equal,
+		                                                                           _routes_temporary_not_available_data_free,
+		                                                                           NULL);
+	}
+
+	for (i = 0; i < routes_temporary_not_available_arr->len; i++) {
+		const NMPObject *o = routes_temporary_not_available_arr->pdata[i];
+		char sbuf[1024];
+
+		nm_assert (NMP_OBJECT_GET_TYPE (o) == NMP_OBJECT_TYPE_IP_ROUTE (NM_IS_IPv4 (addr_family)));
+
+		data = g_hash_table_lookup (self->priv.p->routes_temporary_not_available_hash, &o);
+
+		if (data) {
+			if (!data->dirty)
+				continue;
+
+			nm_assert (   data->timestamp_msec > 0
+			           && data->timestamp_msec <= now_msec);
+
+			if (now_msec > data->timestamp_msec + ROUTES_TEMPORARY_NOT_AVAILABLE_MAX_AGE_MSEC) {
+
+				/* timeout. Could not add this address. */
+				_LOGW ("failure to add IPv%c route: %s",
+				       nm_utils_addr_family_to_char (addr_family),
+				       nmp_object_to_string (o, NMP_OBJECT_TO_STRING_PUBLIC, sbuf, sizeof (sbuf)));
+				success = FALSE;
+				continue;
+			}
+
+			data->dirty = FALSE;
+			continue;
+		}
+
+		_LOGT ("(temporarily) unable to add IPv%c route: %s",
+		       nm_utils_addr_family_to_char (addr_family),
+		       nmp_object_to_string (o, NMP_OBJECT_TO_STRING_PUBLIC, sbuf, sizeof (sbuf)));
+
+		data = g_slice_new (RoutesTemporaryNotAvailableData);
+		*data = (RoutesTemporaryNotAvailableData) {
+			.obj            = nmp_object_ref (o),
+			.timestamp_msec = now_msec,
+			.dirty          = FALSE,
+		};
+		g_hash_table_add (self->priv.p->routes_temporary_not_available_hash, data);
+	}
+
+out_prune:
+	oldest_msec = G_MAXINT64;
+
+	if (self->priv.p->routes_temporary_not_available_hash) {
+		g_hash_table_iter_init (&iter, self->priv.p->routes_temporary_not_available_hash);
+		while (g_hash_table_iter_next (&iter, (gpointer *) &data, NULL)) {
+			nm_assert (   NMP_OBJECT_GET_ADDR_FAMILY (data->obj) == addr_family
+			           || !data->dirty);
+			if (   !prune_all
+			    && !data->dirty) {
+				if (data->timestamp_msec < oldest_msec)
+					oldest_msec = data->timestamp_msec;
+				continue;
+			}
+			g_hash_table_iter_remove (&iter);
+		}
+		if (oldest_msec != G_MAXINT64)
+			nm_clear_pointer (&self->priv.p->routes_temporary_not_available_hash, g_hash_table_unref);
+	}
+
+	nm_clear_g_source (&self->priv.p->routes_temporary_not_available_id);
+	if (oldest_msec != G_MAXINT64) {
+		nm_assert (oldest_msec + ROUTES_TEMPORARY_NOT_AVAILABLE_MAX_AGE_MSEC < now_msec);
+		self->priv.p->routes_temporary_not_available_id = g_timeout_add (oldest_msec + ROUTES_TEMPORARY_NOT_AVAILABLE_MAX_AGE_MSEC - now_msec,
+		                                                                 _routes_temporary_not_available_timeout,
+		                                                                 self);
+	}
+
+	return success;
+}
+
+/*****************************************************************************/
+
 gboolean
 nm_l3cfg_platform_commit (NML3Cfg *self,
-                          int addr_family)
+                          int addr_family,
+                          gboolean *out_final_failure_for_temporary_not_available)
 {
 	gs_unref_ptrarray GPtrArray *addresses = NULL;
 	gs_unref_ptrarray GPtrArray *routes = NULL;
 	gs_unref_ptrarray GPtrArray *routes_prune = NULL;
-	gs_unref_ptrarray GPtrArray *routes_temporary_not_available = NULL;
+	gs_unref_ptrarray GPtrArray *routes_temporary_not_available_arr = NULL;
 	NMIPRouteTableSyncMode route_table_sync = NM_IP_ROUTE_TABLE_SYNC_MODE_NONE;
+	gboolean final_failure_for_temporary_not_available = FALSE;
 	gboolean success = TRUE;
 	int IS_IPv4;
 
 	g_return_val_if_fail (NM_IS_L3CFG (self), FALSE);
 
 	if (addr_family == AF_UNSPEC) {
-		if (!nm_l3cfg_platform_commit (self, AF_INET))
+		gboolean final_failure_for_temporary_not_available_6 = FALSE;
+
+		if (!nm_l3cfg_platform_commit (self, AF_INET, &final_failure_for_temporary_not_available))
 			success = FALSE;
-		if (!nm_l3cfg_platform_commit (self, AF_INET6))
+		if (!nm_l3cfg_platform_commit (self, AF_INET6, &final_failure_for_temporary_not_available_6))
 			success = FALSE;
+		NM_SET_OUT (out_final_failure_for_temporary_not_available,
+		            (   final_failure_for_temporary_not_available
+		             || final_failure_for_temporary_not_available_6));
 		return success;
 	}
 
@@ -622,9 +837,16 @@ nm_l3cfg_platform_commit (NML3Cfg *self,
 	                                self->priv.ifindex,
 	                                routes,
 	                                routes_prune,
-	                                &routes_temporary_not_available))
+	                                &routes_temporary_not_available_arr))
 		success = FALSE;
 
+	final_failure_for_temporary_not_available = FALSE;
+	if (!_routes_temporary_not_available_update (self,
+	                                             addr_family,
+	                                             routes_temporary_not_available_arr))
+		final_failure_for_temporary_not_available = TRUE;
+
+	NM_SET_OUT (out_final_failure_for_temporary_not_available, final_failure_for_temporary_not_available);
 	return success;
 }
 
@@ -705,6 +927,9 @@ finalize (GObject *object)
 
 	nm_assert (nm_g_array_len (self->priv.p->property_emit_list) == 0u);
 
+	nm_clear_g_source (&self->priv.p->routes_temporary_not_available_id);
+	nm_clear_pointer (&self->priv.p->routes_temporary_not_available_hash, g_hash_table_unref);
+
 	g_clear_object (&self->priv.netns);
 	g_clear_object (&self->priv.platform);
 
@@ -744,4 +969,17 @@ nm_l3cfg_class_init (NML3CfgClass *klass)
 	                       G_PARAM_STATIC_STRINGS);
 
 	g_object_class_install_properties (object_class, _PROPERTY_ENUMS_LAST, obj_properties);
+
+	signals[SIGNAL_NOTIFY] =
+	    g_signal_new (NM_L3CFG_SIGNAL_NOTIFY,
+	                  G_OBJECT_CLASS_TYPE (object_class),
+	                    G_SIGNAL_DETAILED
+	                  | G_SIGNAL_RUN_FIRST,
+	                  0, NULL, NULL, NULL,
+	                  G_TYPE_NONE,
+	                  2,
+	                  G_TYPE_INT /* NML3ConfigNotifyType */,
+	                  G_TYPE_POINTER /* pay-load */ );
+
+	signal_notify_quarks[NM_L3_CONFIG_NOTIFY_TYPE_ROUTES_TEMPORARY_NOT_AVAILABLE_EXPIRED] = g_quark_from_static_string (NM_L3_CONFIG_NOTIFY_TYPE_ROUTES_TEMPORARY_NOT_AVAILABLE_EXPIRED_DETAIL);
 }
diff --git a/src/nm-l3cfg.h b/src/nm-l3cfg.h
index 7d77c50596..fefc3e5f0f 100644
--- a/src/nm-l3cfg.h
+++ b/src/nm-l3cfg.h
@@ -16,6 +16,15 @@
 #define NM_L3CFG_NETNS   "netns"
 #define NM_L3CFG_IFINDEX "ifindex"
 
+#define NM_L3CFG_SIGNAL_NOTIFY "l3cfg-notify"
+
+typedef enum {
+	NM_L3_CONFIG_NOTIFY_TYPE_ROUTES_TEMPORARY_NOT_AVAILABLE_EXPIRED,
+	_NM_L3_CONFIG_NOTIFY_TYPE_NUM,
+} NML3ConfigNotifyType;
+
+#define NM_L3_CONFIG_NOTIFY_TYPE_ROUTES_TEMPORARY_NOT_AVAILABLE_EXPIRED_DETAIL "routes-temporary-not-available"
+
 struct _NML3CfgPrivate;
 
 struct _NML3Cfg {
@@ -117,6 +126,7 @@ void nm_l3cfg_remove_config_all (NML3Cfg *self,
 /*****************************************************************************/
 
 gboolean nm_l3cfg_platform_commit (NML3Cfg *self,
-                                   int addr_family);
+                                   int addr_family,
+                                   gboolean *out_final_failure_for_temporary_not_available);
 
 #endif /* __NM_L3CFG_H__ */