From: Tobias Brunner <tobias@strongswan.org>
Date: Mon, 13 Jan 2025 16:09:15 +0000 (+0100)
Subject: plugin-loader: Properly support compilation without dlopen()/dlsym() etc.
X-Git-Tag: android-2.5.3~10
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=d860c26e953330879b373184e032e7f5c6e5463f;p=thirdparty%2Fstrongswan.git

plugin-loader: Properly support compilation without dlopen()/dlsym() etc.

This only works if plugins are built monolithically and linked statically.

Closes strongswan/strongswan#2615
---

diff --git a/src/libstrongswan/plugins/plugin_loader.c b/src/libstrongswan/plugins/plugin_loader.c
index 30b1aeed08..786b183328 100644
--- a/src/libstrongswan/plugins/plugin_loader.c
+++ b/src/libstrongswan/plugins/plugin_loader.c
@@ -191,10 +191,12 @@ struct plugin_entry_t {
 	 */
 	bool critical;
 
+#ifdef HAVE_DLADDR
 	/**
 	 * dlopen handle, if in separate lib
 	 */
 	void *handle;
+#endif
 
 	/**
 	 * List of features, as provided_feature_t
@@ -208,10 +210,12 @@ struct plugin_entry_t {
 static void plugin_entry_destroy(plugin_entry_t *entry)
 {
 	DESTROY_IF(entry->plugin);
+#ifdef HAVE_DLADDR
 	if (entry->handle)
 	{
 		dlclose(entry->handle);
 	}
+#endif
 	entry->features->destroy(entry->features);
 	free(entry);
 }
@@ -369,11 +373,14 @@ static status_t create_plugin(private_plugin_loader_t *this, void *handle,
 	{
 		constructor = plugin_constructors->get(plugin_constructors, name);
 	}
+#elif defined(HAVE_DLADDR)
 	if (!constructor)
-#endif
 	{
 		constructor = dlsym(handle, create);
 	}
+#else
+	#error Neither dynamic linking nor static plugin constructors are supported!
+#endif
 	if (!constructor)
 	{
 		return NOT_FOUND;
@@ -412,8 +419,12 @@ static plugin_entry_t *load_plugin(private_plugin_loader_t *this, char *name,
 {
 	char create[128];
 	plugin_entry_t *entry;
-	void *handle;
+	void *handle = NULL;
+
+#ifdef HAVE_DLADDR
 	int flag = RTLD_LAZY;
+	handle = RTLD_DEFAULT;
+#endif
 
 	if (snprintf(create, sizeof(create), "%s_plugin_create",
 				 name) >= sizeof(create))
@@ -421,7 +432,7 @@ static plugin_entry_t *load_plugin(private_plugin_loader_t *this, char *name,
 		return NULL;
 	}
 	translate(create, "-", "_");
-	switch (create_plugin(this, RTLD_DEFAULT, name, create, FALSE, critical,
+	switch (create_plugin(this, handle, name, create, FALSE, critical,
 						  &entry))
 	{
 		case SUCCESS:
@@ -447,6 +458,7 @@ static plugin_entry_t *load_plugin(private_plugin_loader_t *this, char *name,
 			return NULL;
 		}
 	}
+#ifdef HAVE_DLADDR
 	if (lib->settings->get_bool(lib->settings, "%s.dlopen_use_rtld_now",
 								FALSE, lib->ns))
 	{
@@ -480,6 +492,9 @@ static plugin_entry_t *load_plugin(private_plugin_loader_t *this, char *name,
 	entry->handle = handle;
 	this->plugins->insert_last(this->plugins, entry);
 	return entry;
+#else
+	return NULL;
+#endif
 }
 
 CALLBACK(feature_filter, bool,
@@ -1347,10 +1362,12 @@ METHOD(plugin_loader_t, unload, void,
 	unload_features(this);
 	while (this->plugins->remove_last(this->plugins, (void**)&entry) == SUCCESS)
 	{
+#ifdef HAVE_DLADDR
 		if (lib->leak_detective)
 		{	/* keep handle to report leaks properly */
 			entry->handle = NULL;
 		}
+#endif
 		unregister_features(this, entry);
 		plugin_entry_destroy(entry);
 	}
@@ -1474,9 +1491,12 @@ plugin_loader_t *plugin_loader_create()
 		.features = hashlist_create(
 							(hashtable_hash_t)registered_feature_hash,
 							(hashtable_equals_t)registered_feature_equals, 64),
-		.get_features = dlsym(RTLD_DEFAULT, "plugin_loader_feature_filter"),
 	);
 
+#ifdef HAVE_DLADDR
+	this->get_features = dlsym(RTLD_DEFAULT, "plugin_loader_feature_filter");
+#endif
+
 	if (!this->get_features)
 	{
 		this->get_features = get_features_default;