fix(falco_metrics): remove ifinfo_json stat/metric

Using JSON as value prevents any meaningful aggregation for the stats.
Splitting these information into multiple labels can drastically
increase the number of dimensions, as the number of interfaces and
addresses can be high in some environment. Moreover, these information
are not currently refreshed, even if they can frequently change. Given
these reasons, remove ifinfo_json from stats and metrics.

Signed-off-by: Leonardo Di Giovanna <leonardodigiovanna1@gmail.com>

userspace/falco/falco_metrics.cpp

@@ -111,39 +111,6 @@ std::string falco_metrics::to_text(const falco::app::state& state)
 			prometheus_text += prometheus_metrics_converter.convert_metric_to_text_prometheus("sha256_config_files", "falcosecurity", "falco", {{"file_name", fs_path.filename()}, {"sha256", item.second}});
 		}
 
-		static std::string ifinfo_json_escaped;
-		auto ipv4list = inspector->get_ifaddr_list().get_ipv4_list();
-		auto ipv6list = inspector->get_ifaddr_list().get_ipv6_list();
-		nlohmann::json ipv4_json;
-		nlohmann::json ipv6_json;
-		if(ipv4list)
-		{
-			for (const auto& item : *ipv4list)
-			{
-				if(item.m_name == "lo")
-				{
-					continue;
-				}
-				ipv4_json[item.m_name] = item.addr_to_string();
-			}
-		}
-
-		if(ipv6list)
-		{
-			for (const auto& item : *ipv6list)
-			{
-				if(item.m_name == "lo")
-				{
-					continue;
-				}
-				ipv6_json[item.m_name] = item.addr_to_string();
-			}
-		}
-		nlohmann::json ifinfo_json;
-		ifinfo_json["ipv4"] = ipv4_json;
-		ifinfo_json["ipv6"] = ipv6_json;
-		ifinfo_json_escaped = ifinfo_json.dump();
-		prometheus_text += prometheus_metrics_converter.convert_metric_to_text_prometheus("host_ifinfo_json", "falcosecurity", "falco", {{"host_ifinfo_json", ifinfo_json_escaped}});
 #endif
 
 		for (const std::string& source: inspector->event_sources())

userspace/falco/stats_writer.cpp

@@ -358,39 +358,6 @@ void stats_writer::collector::get_metrics_output_fields_wrapper(
 		output_fields[metric_name_file_sha256] = item.second;
 	}
 
-	auto ipv4list = inspector->get_ifaddr_list().get_ipv4_list();
-	auto ipv6list = inspector->get_ifaddr_list().get_ipv6_list();
-	nlohmann::json ipv4_json;
-	nlohmann::json ipv6_json;
-	if(ipv4list)
-	{
-		for (const auto& item : *ipv4list)
-		{
-			if(item.m_name == "lo")
-			{
-				continue;
-			}
-			ipv4_json[item.m_name] = item.addr_to_string();
-		}
-	}
-
-	if(ipv6list)
-	{
-		for (const auto& item : *ipv6list)
-		{
-			if(item.m_name == "lo")
-			{
-				continue;
-			}
-			ipv6_json[item.m_name] = item.addr_to_string();
-		}
-	}
-	nlohmann::json ifinfo_json;
-	ifinfo_json["ipv4"] = ipv4_json;
-	ifinfo_json["ipv6"] = ipv6_json;
-	m_ifinfo_json_escaped = ifinfo_json.dump();
-	output_fields["falco.host_ifinfo_json"] = m_ifinfo_json_escaped;
-
 #endif
 	output_fields["evt.source"] = src;
 	for (size_t i = 0; i < sizeof(all_driver_engines) / sizeof(const char*); i++)

userspace/falco/stats_writer.h

@@ -80,7 +80,6 @@ class stats_writer
 		uint64_t m_last_n_evts = 0;
 		uint64_t m_last_n_drops = 0;
 		uint64_t m_last_num_evts = 0;
-		std::string m_ifinfo_json_escaped;
 	};
 
 	stats_writer(const stats_writer&) = delete;