client/dbus-proxy.c

/*
 *
 *  Wireless daemon for Linux
 *
 *  Copyright (C) 2017-2020  Intel Corporation. All rights reserved.
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <ell/ell.h>

#include "client/agent-manager.h"
#include "client/dbus-proxy.h"
#include "client/display.h"
#include "client/command.h"
#include "client/properties.h"

#define IWD_SERVICE		"net.connman.iwd"
#define IWD_ROOT_PATH		"/"

struct proxy_interface {
	void *data;
	char *path;
	const struct proxy_interface_type *type;
};

static struct l_dbus *dbus;

static struct l_queue *proxy_interfaces;
static struct l_queue *proxy_interface_types;

void proxy_properties_display(const struct proxy_interface *proxy,
				const char *caption, const char *margin,
				int name_column_width, int value_column_width)
{
	const void *data;
	const struct proxy_interface_property *properties;
	size_t i;

	if (!proxy->type->properties)
		return;

	display_table_header(caption, "%s%-*s  %-*s%-*s", margin,
				8, "Settable",
				name_column_width, "Property",
				value_column_width, "Value");

	data = proxy_interface_get_data(proxy);
	properties = proxy->type->properties;

	for (i = 0; properties[i].name; i++) {
		if (!properties[i].tostr)
			continue;

		display("%s%*s  %-*s%-.*s\n", margin,
			8, properties[i].is_read_write ?
				COLOR_BOLDGRAY "       *" COLOR_OFF : "",
			name_column_width, properties[i].name,
			value_column_width, properties[i].tostr(data) ? : "");
	}
}

static const void *proxy_interface_property_tostr(
					const struct proxy_interface *proxy,
					const char *name)
{
	size_t i;
	const struct proxy_interface_property *property_table =
							proxy->type->properties;

	for (i = 0; property_table[i].name; i++) {
		if (strcmp(property_table[i].name, name))
			continue;

		if (!property_table[i].tostr)
			break;

		return property_table[i].tostr(proxy->data);
	}

	return NULL;
}

static void proxy_interface_property_update(struct proxy_interface *proxy,
					const char *name,
					struct l_dbus_message_iter *variant)
{
	size_t i;
	const struct proxy_interface_property *property_table =
							proxy->type->properties;

	for (i = 0; property_table[i].name; i++) {
		if (strcmp(property_table[i].name, name))
			continue;

		if (!property_table[i].update)
			return;

		property_table[i].update(proxy->data, variant);

		return;
	}

	l_debug("Unknown property name: %s for interface %s", name,
							proxy->type->interface);
}

static void interface_update_properties(struct proxy_interface *proxy,
					struct l_dbus_message_iter *changed,
					struct l_dbus_message_iter *invalidated)
{
	const char *name;
	struct l_dbus_message_iter variant;

	while (l_dbus_message_iter_next_entry(changed, &name, &variant))
		proxy_interface_property_update(proxy, name, &variant);

	if (!invalidated)
		return;

	while (l_dbus_message_iter_next_entry(invalidated, &name))
		proxy_interface_property_update(proxy, name, NULL);
}

static char *strdup_quoted_for_spaces(const char *str)
{
	const char *p;

	for (p = str; *p; p++) {
		if (*p != ' ')
			continue;

		return l_strdup_printf("\"%s\"", str);
	}

	return l_strdup(str);
}

char *proxy_property_str_completion(const struct proxy_interface_type *type,
					proxy_property_match_func_t function,
					const char *property_name,
					const void *value, int state,
					const char *extra_interface)
{
	static struct l_queue *match;
	static const struct l_queue_entry *entry;

	if (!state) {
		match = proxy_interface_find_all(type->interface, function,
									value);
		if (!match)
			return NULL;

		entry = l_queue_get_entries(match);
	}

	while (entry) {
		const struct proxy_interface *proxy = entry->data;
		const char *str;

		entry = entry->next;

		if (extra_interface) {
			const char *path = proxy_interface_get_path(proxy);
			const struct proxy_interface *extra =
				proxy_interface_find(extra_interface, path);

			if (!extra)
				continue;
		}

		str = proxy_interface_property_tostr(proxy, property_name);
		if (!str)
			goto done;

		return strdup_quoted_for_spaces(str);
	}
done:
	l_queue_destroy(match, NULL);
	match = NULL;
	entry = NULL;

	return NULL;
}

static char *proxy_property_completion_value_options(const char **options,
							const char *text,
							int state)
{
	static int index;
	static int len;
	const char *opt;

	if (!state) {
		index = 0;
		len = strlen(text);
	}

	while ((opt = options[index++])) {
		if (strncmp(opt, text, len))
			continue;

		return l_strdup(opt);
	}

	return NULL;
}

char *proxy_property_completion(
			const struct proxy_interface_property *properties,
			const char *text, int state)
{
	static size_t i;
	static size_t j;
	static size_t len;
	static bool first_pass;
	const char *name;

	if (!state) {
		j = 0;
		first_pass = true;
	}

	while (first_pass && (name = properties[j].name)) {
		if (!properties[j].is_read_write)
			goto next;

		if (!command_line_find_token(name, 2))
			goto next;

		if (!properties[j].options)
			goto next;

		return proxy_property_completion_value_options(
					properties[j].options, text,
					state);
next:
		j++;
	}

	if (first_pass) {
		i = 0;
		first_pass = false;
		len = strlen(text);
	}

	while ((name = properties[i].name)) {
		if (!properties[i++].is_read_write)
			continue;

		if (strncmp(name, text, len))
			continue;

		return l_strdup(name);
	}

	return NULL;
}

static const struct proxy_interface_property *proxy_property_find(
				const struct proxy_interface_property *types,
				const char *name)
{
	size_t i;

	for (i = 0; types[i].name; i++) {
		if (strcmp(types[i].name, name))
			continue;

		return &types[i];
	}

	return NULL;
}

struct proxy_callback_data {
	l_dbus_message_func_t callback;
	void *user_data;
};

static void proxy_callback(struct l_dbus_message *message, void *user_data)
{
	struct proxy_callback_data *callback_data = user_data;
	const struct proxy_interface *proxy;
	const char *name;
	const char *text;

	if (callback_data->callback)
		callback_data->callback(message, callback_data->user_data);

	if (command_is_interactive_mode())
		return;

	if (l_dbus_message_get_error(message, &name, &text)) {
		command_set_exit_status(EXIT_FAILURE);
		goto quit;
	}

	proxy = callback_data->user_data;
	if (!strcmp(proxy->type->interface, IWD_AGENT_MANAGER_INTERFACE))
		return;

quit:
	l_main_quit();
}

bool proxy_property_set(const struct proxy_interface *proxy, const char *name,
			const char *value_str, l_dbus_message_func_t callback)
{
	struct l_dbus_message_builder *builder;
	struct l_dbus_message *msg;
	const struct proxy_interface_property *property;
	struct proxy_callback_data *callback_data;

	if (!proxy || !name)
		return false;

	property = proxy_property_find(proxy->type->properties, name);
	if (!property)
		return false;

	if (!property->is_read_write)
		return false;

	if (!property->append)
		return false;

	msg = l_dbus_message_new_method_call(dbus, IWD_SERVICE, proxy->path,
						L_DBUS_INTERFACE_PROPERTIES,
						"Set");
	if (!msg)
		return false;


	builder = l_dbus_message_builder_new(msg);
	if (!builder) {
		l_dbus_message_unref(msg);
		return false;
	}

	l_dbus_message_builder_append_basic(builder, 's',
							proxy->type->interface);
	l_dbus_message_builder_append_basic(builder, 's', property->name);
	l_dbus_message_builder_enter_variant(builder, property->type);

	if (!property->append(builder, value_str)) {
		l_dbus_message_builder_destroy(builder);
		l_dbus_message_unref(msg);
		return false;
	}

	l_dbus_message_builder_leave_variant(builder);
	l_dbus_message_builder_finalize(builder);
	l_dbus_message_builder_destroy(builder);

	callback_data = l_new(struct proxy_callback_data, 1);
	callback_data->callback = callback;
	callback_data->user_data = (void *) proxy;

	l_dbus_send_with_reply(dbus, msg, proxy_callback, callback_data,
									l_free);

	return true;
}

bool dbus_message_has_error(struct l_dbus_message *message)
{
	const char *name;
	const char *text;

	if (l_dbus_message_get_error(message, &name, &text)) {
		display_error(text);
		return true;
	}

	return false;
}

static bool interface_match_by_type_name(const void *a, const void *b)
{
	const struct proxy_interface_type *type = a;
	const char *interface = b;

	return !strcmp(type->interface, interface);
}

struct proxy_interface *proxy_interface_find(const char *interface,
							const char *path)
{
	const struct l_queue_entry *entry;

	if (!interface || !path)
		return NULL;

	for (entry = l_queue_get_entries(proxy_interfaces); entry;
							entry = entry->next) {
		struct proxy_interface *proxy = entry->data;

		if (strcmp(proxy->path, path))
			continue;

		if (strcmp(proxy->type->interface, interface))
			continue;

		return proxy;
	}

	return NULL;
}

struct l_queue *proxy_interface_find_all(const char *interface,
					proxy_property_match_func_t function,
					const void *value)
{
	const struct l_queue_entry *entry;
	struct l_queue *match = NULL;

	if (!interface)
		return NULL;

	for (entry = l_queue_get_entries(proxy_interfaces); entry;
							entry = entry->next) {
		struct proxy_interface *proxy = entry->data;

		if (!interface_match_by_type_name(proxy->type, interface))
			continue;

		if (function && !function(proxy->data, value))
			continue;

		if (!match)
			match = l_queue_new();

		l_queue_push_tail(match, proxy);
	}

	return match;
}

bool proxy_interface_is_same(const struct proxy_interface *a,
					const struct proxy_interface *b)
{
	return !strcmp(a->path, b->path);
}

static void properties_changed_callback(struct l_dbus_message *message,
								void *data)
{
	struct proxy_interface *proxy;
	const char *path;
	const char *interface;
	struct l_dbus_message_iter changed;
	struct l_dbus_message_iter invalidated;

	if (dbus_message_has_error(message))
		return;

	if (!l_dbus_message_get_arguments(message, "sa{sv}as", &interface,
						&changed, &invalidated)) {
		l_debug("Failed to parse properties changed callback message");

		return;
	}

	path = l_dbus_message_get_path(message);
	if (!path)
		return;

	proxy = proxy_interface_find(interface, path);
	if (!proxy)
		return;

	interface_update_properties(proxy, &changed, &invalidated);
}

static bool is_ignorable(const char *interface)
{
	size_t i;

	static const struct {
		const char *interface;
	} interfaces_to_ignore[] = {
		{ L_DBUS_INTERFACE_OBJECT_MANAGER },
		{ L_DBUS_INTERFACE_INTROSPECTABLE },
		{ L_DBUS_INTERFACE_PROPERTIES },
		{ }
	};

	for (i = 0; interfaces_to_ignore[i].interface; i++)
		if (!strcmp(interfaces_to_ignore[i].interface, interface))
			return true;

	return false;
}

static void proxy_interfaces_update_properties(const char *path,
					struct l_dbus_message_iter *interfaces)
{
	const char *interface;
	struct l_dbus_message_iter properties;
	struct proxy_interface *proxy;
	struct proxy_interface_type *interface_type;

	if (!path)
		return;

	while (l_dbus_message_iter_next_entry(interfaces, &interface,
								&properties)) {
		interface_type = l_queue_find(proxy_interface_types,
						interface_match_by_type_name,
						interface);
		if (!interface_type)
			continue;

		proxy = proxy_interface_find(interface_type->interface, path);
		if (!proxy)
			continue;

		interface_update_properties(proxy, &properties, NULL);
	}
}

static void proxy_interface_create(const char *path,
					struct l_dbus_message_iter *interfaces)
{
	const char *interface;
	struct l_dbus_message_iter properties;
	struct proxy_interface *proxy;
	struct proxy_interface_type *interface_type;

	if (!path)
		return;

	while (l_dbus_message_iter_next_entry(interfaces, &interface,
								&properties)) {
		interface_type = l_queue_find(proxy_interface_types,
						interface_match_by_type_name,
						interface);

		if (!interface_type) {
			if (!is_ignorable(interface))
				l_debug("Unknown DBus interface type %s",
								interface);

			continue;
		}

		proxy = proxy_interface_find(interface_type->interface, path);

		if (proxy)
			continue;

		proxy = l_new(struct proxy_interface, 1);
		proxy->path = l_strdup(path);
		proxy->type = interface_type;

		l_queue_push_tail(proxy_interfaces, proxy);

		if (interface_type->ops && interface_type->ops->create)
			proxy->data = interface_type->ops->create();
	}
}

static void proxy_interface_destroy(void *data)
{
	struct proxy_interface *proxy = data;

	l_free(proxy->path);

	if (proxy->type->ops && proxy->type->ops->destroy)
		proxy->type->ops->destroy(proxy->data);

	proxy->type = NULL;

	l_free(proxy);
}

bool proxy_interface_method_call(const struct proxy_interface *proxy,
					const char *name, const char *signature,
					l_dbus_message_func_t callback, ...)
{
	struct proxy_callback_data *callback_data;
	struct l_dbus_message *call;
	va_list args;

	if (!proxy || !name)
		return false;

	call = l_dbus_message_new_method_call(dbus, IWD_SERVICE, proxy->path,
						 proxy->type->interface, name);

	va_start(args, callback);
	l_dbus_message_set_arguments_valist(call, signature, args);
	va_end(args);

	callback_data = l_new(struct proxy_callback_data, 1);
	callback_data->callback = callback;
	callback_data->user_data = (void *) proxy;

	l_dbus_send_with_reply(dbus, call, proxy_callback, callback_data,
									l_free);

	return true;
}

void *proxy_interface_get_data(const struct proxy_interface *proxy)
{
	return proxy->data;
}

const char *proxy_interface_get_interface(const struct proxy_interface *proxy)
{
	return proxy->type->interface;
}

const char *proxy_interface_get_path(const struct proxy_interface *proxy)
{
	return proxy->path;
}

const char *proxy_interface_get_identity_str(
					const struct proxy_interface *proxy)
{
	if (proxy->type->ops && proxy->type->ops->identity)
		return proxy->type->ops->identity(proxy->data);

	return NULL;
}

void proxy_interface_display_list(const char *interface)
{
	const struct l_queue_entry *entry;

	for (entry = l_queue_get_entries(proxy_interfaces); entry;
							entry = entry->next) {
		const struct proxy_interface *proxy = entry->data;

		if (!interface_match_by_type_name(proxy->type, interface))
			continue;

		if (!proxy->type->ops || !proxy->type->ops->display)
			break;

		proxy->type->ops->display(MARGIN, proxy->data);
	}
}

static void interfaces_added_callback(struct l_dbus_message *message,
								void *user_data)
{
	const char *path;
	struct l_dbus_message_iter object;

	if (dbus_message_has_error(message))
		return;

	if (!l_dbus_message_get_arguments(message, "oa{sa{sv}}", &path,
								&object))
		return;

	proxy_interface_create(path, &object);

	if (!l_dbus_message_get_arguments(message, "oa{sa{sv}}", &path,
								&object))
		return;

	proxy_interfaces_update_properties(path, &object);
}

static void interfaces_removed_callback(struct l_dbus_message *message,
								void *user_data)
{
	const char *interface;
	const char *path;
	struct l_dbus_message_iter interfaces;
	struct proxy_interface *proxy;

	if (dbus_message_has_error(message))
		return;

	if (!l_dbus_message_get_arguments(message, "oas", &path, &interfaces))
		return;

	while (l_dbus_message_iter_next_entry(&interfaces, &interface)) {
		proxy = proxy_interface_find(interface, path);

		if (!proxy)
			continue;

		l_queue_remove(proxy_interfaces, proxy);

		proxy_interface_destroy(proxy);
	}
}

static void get_managed_objects_callback(struct l_dbus_message *message,
								void *user_data)
{
	struct l_dbus_message_iter objects;
	struct l_dbus_message_iter object;
	const char *path;

	if (dbus_message_has_error(message)) {
		display_error("Failed to retrieve IWD dbus objects, "
							"quitting...\n");

		goto error;
	}

	if (!l_dbus_message_get_arguments(message, "a{oa{sa{sv}}}", &objects)) {
		display_error("Failed to parse IWD dbus objects, "
							"quitting...\n");

		goto error;
	}

	while (l_dbus_message_iter_next_entry(&objects, &path, &object))
		proxy_interface_create(path, &object);

	if (!l_dbus_message_get_arguments(message, "a{oa{sa{sv}}}", &objects))
		/*
		 * Shouldn't happen since we parsed it above, but check return
		 * anyway.
		 */
		goto error;

	while (l_dbus_message_iter_next_entry(&objects, &path, &object))
		proxy_interfaces_update_properties(path, &object);

	if (command_is_interactive_mode())
		display_enable_cmd_prompt();
	else
		command_noninteractive_trigger();

	return;

error:
	if (!command_is_interactive_mode())
		command_set_exit_status(EXIT_FAILURE);

	l_main_quit();
}

static void get_managed_objects(void)
{
	l_dbus_method_call(dbus, IWD_SERVICE, IWD_ROOT_PATH,
					L_DBUS_INTERFACE_OBJECT_MANAGER,
					"GetManagedObjects", NULL,
					get_managed_objects_callback,
					NULL, NULL);
}

static void service_appeared_callback(struct l_dbus *dbus, void *user_data)
{
	l_dbus_add_signal_watch(dbus, IWD_SERVICE, IWD_ROOT_PATH,
					L_DBUS_INTERFACE_OBJECT_MANAGER,
					"InterfacesAdded", L_DBUS_MATCH_NONE,
					interfaces_added_callback, NULL);

	l_dbus_add_signal_watch(dbus, IWD_SERVICE, IWD_ROOT_PATH,
					L_DBUS_INTERFACE_OBJECT_MANAGER,
					"InterfacesRemoved", L_DBUS_MATCH_NONE,
					interfaces_removed_callback, NULL);

	l_dbus_add_signal_watch(dbus, IWD_SERVICE, NULL,
					L_DBUS_INTERFACE_PROPERTIES,
					"PropertiesChanged", L_DBUS_MATCH_NONE,
					properties_changed_callback, NULL);

	get_managed_objects();
}

static void service_disappeared_callback(struct l_dbus *dbus,
							void *user_data)
{
	if (!command_is_interactive_mode()) {
		command_set_exit_status(EXIT_FAILURE);
		l_main_quit();
	}

	l_queue_clear(proxy_interfaces, proxy_interface_destroy);

	command_reset_default_entities();

	display_disable_cmd_prompt();
}

static void dbus_disconnect_callback(void *user_data)
{
	if (!command_is_interactive_mode())
		return;

	l_main_quit();
}

void proxy_interface_type_register(
			const struct proxy_interface_type *interface_type)
{
	l_queue_push_tail(proxy_interface_types, (void *) interface_type);
}

void proxy_interface_type_unregister(
			const struct proxy_interface_type *interface_type)
{
	l_queue_remove(proxy_interface_types, (void *) interface_type);
}

struct l_dbus *dbus_get_bus(void)
{
	return dbus;
}

extern struct interface_type_desc __start___interface[];
extern struct interface_type_desc __stop___interface[];

bool dbus_proxy_init(void)
{
	struct interface_type_desc *desc;

	if (dbus)
		return true;

	dbus = l_dbus_new_default(L_DBUS_SYSTEM_BUS);
	if (!dbus)
		return false;

	proxy_interface_types = l_queue_new();
	proxy_interfaces = l_queue_new();

	for (desc = __start___interface; desc < __stop___interface; desc++) {
		if (!desc->init)
			continue;

		desc->init();
	}

	l_dbus_set_disconnect_handler(dbus, dbus_disconnect_callback, NULL,
									NULL);

	if (command_is_interactive_mode())
		l_dbus_add_service_watch(dbus, IWD_SERVICE,
						service_appeared_callback,
						service_disappeared_callback,
						NULL, NULL);
	else
		get_managed_objects();

	return true;
}

bool dbus_proxy_exit(void)
{
	struct interface_type_desc *desc;

	agent_manager_unregister_agent();

	for (desc = __start___interface; desc < __stop___interface; desc++) {
		if (!desc->exit)
			continue;

		desc->exit();
	}

	l_queue_destroy(proxy_interface_types, NULL);
	proxy_interface_types = NULL;

	l_queue_destroy(proxy_interfaces, proxy_interface_destroy);
	proxy_interfaces = NULL;

	l_dbus_destroy(dbus);
	dbus = NULL;

	return true;
}