permissions: use current_client for security checks

Don't pass around the client object but keep track of the current
client in the core object. This way we don't need to add a client
argument to functions and can check security when needed.

src/modules/module-autolink.c

@@ -204,7 +204,7 @@ static void try_link_port(struct pw_node *node, struct pw_port *port, struct nod
 
 	pw_log_debug("module %p: try to find and link to node '%d'", impl, path_id);
 
-	target = pw_core_find_port(impl->core, owner, port, path_id, NULL, 0, NULL, &error);
+	target = pw_core_find_port(impl->core, port, path_id, NULL, 0, NULL, &error);
 	if (target == NULL)
 		goto error;
 

src/modules/module-jack.c

@@ -874,8 +874,11 @@ static int
 process_messages(struct client *client)
 {
 	struct pw_client *c = client->client;
+	struct pw_core *core = c->core;
 	int type, res = -1;
 
+	core->current_client = c;
+
 	if (read(client->fd, &type, sizeof(enum jack_request_type)) != sizeof(enum jack_request_type)) {
 		pw_log_error("protocol-jack %p: failed to read type", client->impl);
 		goto error;
@@ -951,12 +954,15 @@ process_messages(struct client *client)
 	if (res != 0)
 		goto error;
 
+      exit:
+	core->current_client = NULL;
 	return res;
 
       error:
 	pw_log_error("protocol-jack %p: error handling type %d", client->impl, type);
 	pw_client_destroy(c);
-	return -1;
+	res = -EIO;
+	goto exit;
 
 }
 
@@ -1351,7 +1357,7 @@ static bool init_nodes(struct impl *impl)
 	make_audio_client(impl);
 	make_freewheel_client(impl);
 
-	pw_core_for_each_global(core, NULL, on_global, impl);
+	pw_core_for_each_global(core, on_global, impl);
 
 	return true;
 }

src/modules/module-link-factory.c

@@ -83,13 +83,13 @@ static void *create_object(void *_data,
 	core = pw_client_get_core(client);
 	t = pw_core_get_type(core);
 
-	global = pw_core_find_global(core, client, output_node_id);
+	global = pw_core_find_global(core, output_node_id);
 	if (global == NULL || pw_global_get_type(global) != t->node)
 		goto no_output;
 
 	output_node = pw_global_get_object(global);
 
-	global = pw_core_find_global(core, client, input_node_id);
+	global = pw_core_find_global(core, input_node_id);
 	if (global == NULL || pw_global_get_type(global) != t->node)
 		goto no_input;
 

src/modules/module-mixer.c

@@ -233,7 +233,7 @@ static int module_init(struct pw_module *module, struct pw_properties *propertie
 
 	spa_list_init(&impl->node_list);
 
-	pw_core_for_each_global(core, NULL, on_global, impl);
+	pw_core_for_each_global(core, on_global, impl);
 
 	pw_core_add_listener(core, &impl->core_listener, &core_events, impl);
 	pw_module_add_listener(module, &impl->module_listener, &module_events, impl);

src/modules/module-protocol-native.c

@@ -168,11 +168,14 @@ process_messages(struct client_data *data)
 {
 	struct pw_protocol_native_connection *conn = data->connection;
 	struct pw_client *client = data->client;
+	struct pw_core *core = client->core;
 	uint8_t opcode;
 	uint32_t id;
 	uint32_t size;
 	void *message;
 
+	core->current_client = client;
+
 	while (pw_protocol_native_connection_get_next(conn, &opcode, &id, &message, &size)) {
 		struct pw_resource *resource;
 		const struct pw_protocol_native_demarshal *demarshal;
@@ -222,18 +225,20 @@ process_messages(struct client_data *data)
 		if (demarshal[opcode].func(resource, message, size) < 0)
 			goto invalid_message;
 	}
+      done:
+	core->current_client = NULL;
 	return;
 
       invalid_method:
 	pw_log_error("protocol-native %p: invalid method %u on resource %u",
 		     client->protocol, opcode, id);
 	pw_client_destroy(client);
-	return;
+	goto done;
       invalid_message:
 	pw_log_error("protocol-native %p: invalid message received %u %u",
 		     client->protocol, id, opcode);
 	pw_client_destroy(client);
-	return;
+	goto done;
 }
 
 static void