Added ICMP flood alert (#5904)

scripts/lua/modules/check_definitions/host/icmp_flood.lua

@@ -0,0 +1,35 @@
+--
+-- (C) 2019-21 - ntop.org
+--
+
+local checks = require("checks")
+local host_alert_keys = require "host_alert_keys"
+
+-- #################################################################
+
+local icmp_flood = {
+   -- Script category
+   category = checks.check_categories.security,
+
+   default_enabled = false,
+   alert_id = host_alert_keys.host_alert_icmp_flood,
+
+   default_value = {
+      operator = "gt",
+      threshold = 256,
+   },
+
+   gui = {
+      i18n_title = "entity_thresholds.icmp_flood_title",
+      i18n_description = "entity_thresholds.icmp_flood_description",
+      i18n_field_unit = checks.field_units.icmp_sec,
+      input_builder = "threshold_cross",
+      field_max = 65535,
+      field_min = 1,
+      field_operator = "gt";
+   }
+}
+
+-- #################################################################
+
+return icmp_flood