new(sinsp)!: support linux_hostinfo_platform in sinsp::open_plugin

Rather than passing the mode directly, introduce a new enum that describes both the mode and the platform to use. Fixes: #2281 Signed-off-by: Grzegorz Nosek <[email protected]>
falcosecurity · Aug 1, 2024 · 2118fcd · 2118fcd
1 parent 90b888f
commit 2118fcd
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Showing 3 changed files with 40 additions and 13 deletions.
diff --git a/userspace/libsinsp/sinsp.cpp b/userspace/libsinsp/sinsp.cpp
@@ -553,7 +553,8 @@ void sinsp::open_savefile(const std::string& filename, int fd)
 #endif
 }
 
-void sinsp::open_plugin(const std::string& plugin_name, const std::string& plugin_open_params, sinsp_mode_t mode)
+void sinsp::open_plugin(const std::string& plugin_name, const std::string& plugin_open_params,
+			sinsp_plugin_platform platform_type)
 {
 #ifdef HAS_ENGINE_SOURCE_PLUGIN
 	scap_open_args oargs {};
@@ -564,16 +565,23 @@ void sinsp::open_plugin(const std::string& plugin_name, const std::string& plugi
 	oargs.engine_params = &params;
 
 	scap_platform* platform;
-	switch(mode)
+	sinsp_mode_t mode;
+	switch(platform_type)
 	{
-		case SINSP_MODE_PLUGIN:
-			platform = scap_generic_alloc_platform(::on_new_entry_from_proc, this);
-			break;
-		case SINSP_MODE_LIVE:
-			platform = scap_linux_alloc_platform(::on_new_entry_from_proc, this);
-			break;
-		default:
-			throw sinsp_exception("Unsupported mode for SOURCE_PLUGIN engine");
+	case sinsp_plugin_platform::SINSP_PLATFORM_GENERIC:
+		mode = SINSP_MODE_PLUGIN;
+		platform = scap_generic_alloc_platform(::on_new_entry_from_proc, this);
+		break;
+	case sinsp_plugin_platform::SINSP_PLATFORM_HOSTINFO:
+		mode = SINSP_MODE_PLUGIN;
+		platform = scap_linux_hostinfo_alloc_platform();
+		break;
+	case sinsp_plugin_platform::SINSP_PLATFORM_FULL:
+		mode = SINSP_MODE_LIVE;
+		platform = scap_linux_alloc_platform(::on_new_entry_from_proc, this);
+		break;
+	default:
+		throw sinsp_exception("Unsupported mode for SOURCE_PLUGIN engine");
 	}
 	open_common(&oargs, &scap_source_plugin_engine, platform, mode);
 #else

diff --git a/userspace/libsinsp/sinsp.h b/userspace/libsinsp/sinsp.h
@@ -139,6 +139,16 @@ enum sinsp_mode_t
 	SINSP_MODE_TEST,
 };
 
+/**
+ * @brief Possible platforms to use with plugins
+ */
+enum class sinsp_plugin_platform
+{
+	SINSP_PLATFORM_GENERIC, //!< generic platform, no system information collected
+	SINSP_PLATFORM_HOSTINFO, //!< basic host information collected, for non-syscall source plugins
+	SINSP_PLATFORM_FULL, //!< full system information collected, for syscall source plugins
+};
+
 /** @defgroup inspector Main library
  @{
 */
@@ -168,7 +178,7 @@ class SINSP_PUBLIC sinsp : public capture_stats_source
 	virtual void open_nodriver(bool full_proc_scan = false);
 	virtual void open_savefile(const std::string &filename, int fd = 0);
 	virtual void open_plugin(const std::string& plugin_name, const std::string& plugin_open_params,
-				 sinsp_mode_t mode = SINSP_MODE_PLUGIN);
+				 sinsp_plugin_platform platform_type);
 	virtual void open_gvisor(const std::string &config_path, const std::string &root_path, bool no_events = false, int epoll_timeout = -1);
 	/*[EXPERIMENTAL] This API could change between releases, we are trying to find the right configuration to deploy the modern bpf probe:
 	 * `cpus_for_each_buffer` and `online_only` are the 2 experimental params. The first one allows associating more than one CPU to a single ring buffer.

diff --git a/userspace/libsinsp/test/plugins.ut.cpp b/userspace/libsinsp/test/plugins.ut.cpp
@@ -273,7 +273,13 @@ TEST_F(sinsp_with_test_input, plugin_syscall_source)
 
 	// we will not use the test scap engine here, but open the src plugin instead
 	// note: we configure the plugin to just emit 1 event through its open params
-	m_inspector.open_plugin(src_pl->name(), "1");
+	m_inspector.open_plugin(src_pl->name(), "1", sinsp_plugin_platform::SINSP_PLATFORM_HOSTINFO);
+
+#ifdef __linux__
+	// The LINUX_HOSTINFO platform type fills in machine_info, but only on Linux
+	// (non-Linux platforms have a stub implementation in scap.c)
+	ASSERT_GT(m_inspector.get_machine_info()->num_cpus, 0);
+#endif
 
 	auto evt = next_event();
 	ASSERT_NE(evt, nullptr);
@@ -310,7 +316,10 @@ TEST_F(sinsp_with_test_input, plugin_custom_source)
 
 	// we will not use the test scap engine here, but open the src plugin instead
 	// note: we configure the plugin to just emit 1 event through its open params
-	m_inspector.open_plugin(src_pl->name(), "1");
+	m_inspector.open_plugin(src_pl->name(), "1", sinsp_plugin_platform::SINSP_PLATFORM_GENERIC);
+
+	// the GENERIC platform type does not fill in machine_info
+	ASSERT_EQ(m_inspector.get_machine_info()->num_cpus, 0);
 
 	auto evt = next_event();
 	ASSERT_NE(evt, nullptr);