/*
 *
 *  Connection Manager
 *
 *  Copyright (C) 2007-2010  Intel Corporation. All rights reserved.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 2 as
 *  published by the Free Software Foundation.
 *
 *  This program 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; 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 <unistd.h>
#include <string.h>
#include <sys/vfs.h>
#include <sys/inotify.h>
#include <glib.h>

#include "connman.h"

struct connman_config_service {
	char *ident;
	char *name;
	char *type;
	void *ssid;
	unsigned int ssid_len;
	char *eap;
	char *identity;
	char *ca_cert_file;
	char *client_cert_file;
	char *private_key_file;
	char *private_key_passphrase;
	char *private_key_passphrase_type;
	char *phase2;
	char *passphrase;
};

struct connman_config {
	char *ident;
	char *name;
	char *description;
	GHashTable *service_table;
};

static GHashTable *config_table = NULL;

static int inotify_wd = -1;

static GIOChannel *inotify_channel = NULL;
static uint inotify_watch = 0;

/* Definition of possible strings in the .config files */
#define CONFIG_KEY_NAME                "Name"
#define CONFIG_KEY_DESC                "Description"

#define SERVICE_KEY_TYPE               "Type"
#define SERVICE_KEY_NAME               "Name"
#define SERVICE_KEY_SSID               "SSID"
#define SERVICE_KEY_EAP                "EAP"
#define SERVICE_KEY_CA_CERT            "CACertFile"
#define SERVICE_KEY_CL_CERT            "ClientCertFile"
#define SERVICE_KEY_PRV_KEY            "PrivateKeyFile"
#define SERVICE_KEY_PRV_KEY_PASS       "PrivateKeyPassphrase"
#define SERVICE_KEY_PRV_KEY_PASS_TYPE  "PrivateKeyPassphraseType"
#define SERVICE_KEY_IDENTITY           "Identity"
#define SERVICE_KEY_PHASE2             "Phase2"
#define SERVICE_KEY_PASSPHRASE         "Passphrase"

static const char *config_possible_keys[] = {
	CONFIG_KEY_NAME,
	CONFIG_KEY_DESC,
	NULL,
};

static const char *service_possible_keys[] = {
	SERVICE_KEY_TYPE,
	SERVICE_KEY_NAME,
	SERVICE_KEY_SSID,
	SERVICE_KEY_EAP,
	SERVICE_KEY_CA_CERT,
	SERVICE_KEY_CL_CERT,
	SERVICE_KEY_PRV_KEY,
	SERVICE_KEY_PRV_KEY_PASS,
	SERVICE_KEY_PRV_KEY_PASS_TYPE,
	SERVICE_KEY_IDENTITY,
	SERVICE_KEY_PHASE2,
	SERVICE_KEY_PASSPHRASE,
	NULL,
};

static void unregister_config(gpointer data)
{
	struct connman_config *config = data;

	connman_info("Removing configuration %s", config->ident);

	g_hash_table_destroy(config->service_table);

	g_free(config->description);
	g_free(config->name);
	g_free(config->ident);
	g_free(config);
}

static void unregister_service(gpointer data)
{
	struct connman_config_service *service = data;

	connman_info("Removing service configuration %s", service->ident);

	g_free(service->ident);
	g_free(service->type);
	g_free(service->name);
	g_free(service->ssid);
	g_free(service->eap);
	g_free(service->identity);
	g_free(service->ca_cert_file);
	g_free(service->client_cert_file);
	g_free(service->private_key_file);
	g_free(service->private_key_passphrase);
	g_free(service->private_key_passphrase_type);
	g_free(service->phase2);
	g_free(service->passphrase);
	g_free(service);
}

static void check_keys(GKeyFile *keyfile, const char *group,
			const char **possible_keys)
{
	char **avail_keys;
	gsize nb_avail_keys, i, j;

	avail_keys = g_key_file_get_keys(keyfile, group, &nb_avail_keys, NULL);
	if (avail_keys == NULL)
		return;

	/*
	 * For each key in the configuration file,
	 * verify it is understood by connman
	 */
	for (i = 0 ; i < nb_avail_keys; i++) {
		for (j = 0; possible_keys[j] ; j++)
			if (g_strcmp0(avail_keys[i], possible_keys[j]) == 0)
				break;

		if (possible_keys[j] == NULL)
			connman_warn("Unknown configuration key %s in [%s]",
					avail_keys[i], group);
	}

	g_strfreev(avail_keys);
}

static int load_service(GKeyFile *keyfile, const char *group,
						struct connman_config *config)
{
	struct connman_config_service *service;
	const char *ident;
	char *str, *hex_ssid;

	/* Strip off "service_" prefix */
	ident = group + 8;

	if (strlen(ident) < 1)
		return -EINVAL;

	/* Verify that provided keys are good */
	check_keys(keyfile, group, service_possible_keys);

	service = g_hash_table_lookup(config->service_table, ident);
	if (service == NULL) {
		service = g_try_new0(struct connman_config_service, 1);
		if (service == NULL)
			return -ENOMEM;

		service->ident = g_strdup(ident);
	}

	str = g_key_file_get_string(keyfile, group, SERVICE_KEY_TYPE, NULL);
	if (str != NULL) {
		g_free(service->type);
		service->type = str;
	}

	str = g_key_file_get_string(keyfile, group, SERVICE_KEY_NAME, NULL);
	if (str != NULL) {
		g_free(service->name);
		service->name = str;
	}

	hex_ssid = g_key_file_get_string(keyfile, group, SERVICE_KEY_SSID,
					 NULL);
	if (hex_ssid != NULL) {
		char *ssid;
		unsigned int i, j = 0, hex;
		size_t hex_ssid_len = strlen(hex_ssid);

		ssid = g_try_malloc0(hex_ssid_len / 2);
		if (ssid == NULL) {
			g_free(hex_ssid);
			return -ENOMEM;
		}

		for (i = 0; i < hex_ssid_len; i += 2) {
			sscanf(hex_ssid + i, "%02x", &hex);
			ssid[j++] = hex;
		}

		g_free(hex_ssid);

		g_free(service->ssid);
		service->ssid = ssid;
		service->ssid_len = hex_ssid_len / 2;
	} else if (service->name != NULL) {
		char *ssid;
		unsigned int ssid_len;

		ssid_len = strlen(service->name);
		ssid = g_try_malloc0(ssid_len);
		if (ssid == NULL)
			return -ENOMEM;

		memcpy(ssid, service->name, ssid_len);
		g_free(service->ssid);
		service->ssid = ssid;
		service->ssid_len = ssid_len;
	}

	str = g_key_file_get_string(keyfile, group, SERVICE_KEY_EAP, NULL);
	if (str != NULL) {
		g_free(service->eap);
		service->eap = str;
	}

	str = g_key_file_get_string(keyfile, group, SERVICE_KEY_CA_CERT, NULL);
	if (str != NULL) {
		g_free(service->ca_cert_file);
		service->ca_cert_file = str;
	}

	str = g_key_file_get_string(keyfile, group, SERVICE_KEY_CL_CERT, NULL);
	if (str != NULL) {
		g_free(service->client_cert_file);
		service->client_cert_file = str;
	}

	str = g_key_file_get_string(keyfile, group, SERVICE_KEY_PRV_KEY, NULL);
	if (str != NULL) {
		g_free(service->private_key_file);
		service->private_key_file = str;
	}

	str = g_key_file_get_string(keyfile, group,
						SERVICE_KEY_PRV_KEY_PASS, NULL);
	if (str != NULL) {
		g_free(service->private_key_passphrase);
		service->private_key_passphrase = str;
	}

	str = g_key_file_get_string(keyfile, group,
					SERVICE_KEY_PRV_KEY_PASS_TYPE, NULL);
	if (str != NULL) {
		g_free(service->private_key_passphrase_type);
		service->private_key_passphrase_type = str;
	}

	str = g_key_file_get_string(keyfile, group, SERVICE_KEY_IDENTITY, NULL);
	if (str != NULL) {
		g_free(service->identity);
		service->identity = str;
	}

	str = g_key_file_get_string(keyfile, group, SERVICE_KEY_PHASE2, NULL);
	if (str != NULL) {
		g_free(service->phase2);
		service->phase2 = str;
	}

	str = g_key_file_get_string(keyfile, group, SERVICE_KEY_PASSPHRASE,
					NULL);
	if (str != NULL) {
		g_free(service->passphrase);
		service->passphrase = str;
	}

	g_hash_table_replace(config->service_table, service->ident, service);

	connman_info("Adding service configuration %s", service->ident);

	return 0;
}

static int load_config(struct connman_config *config)
{
	GKeyFile *keyfile;
	gsize length;
	char **groups;
	char *str;
	int i;

	DBG("config %p", config);

	keyfile = __connman_storage_open_config(config->ident);
	if (keyfile == NULL)
		return -EIO;

	/* Verify keys validity of the global section */
	check_keys(keyfile, "global", config_possible_keys);

	str = g_key_file_get_string(keyfile, "global", CONFIG_KEY_NAME, NULL);
	if (str != NULL) {
		g_free(config->name);
		config->name = str;
	}

	str = g_key_file_get_string(keyfile, "global", CONFIG_KEY_DESC, NULL);
	if (str != NULL) {
		g_free(config->description);
		config->description = str;
	}

	groups = g_key_file_get_groups(keyfile, &length);

	for (i = 0; groups[i] != NULL; i++) {
		if (g_str_has_prefix(groups[i], "service_") == TRUE)
			load_service(keyfile, groups[i], config);
	}

	g_strfreev(groups);

	__connman_storage_close_config(config->ident, keyfile, FALSE);

	return 0;
}

static struct connman_config *create_config(const char *ident)
{
	struct connman_config *config;

	DBG("ident %s", ident);

	if (g_hash_table_lookup(config_table, ident) != NULL)
		return NULL;

	config = g_try_new0(struct connman_config, 1);
	if (config == NULL)
		return NULL;

	config->ident = g_strdup(ident);

	config->service_table = g_hash_table_new_full(g_str_hash, g_str_equal,
						NULL, unregister_service);

	g_hash_table_insert(config_table, config->ident, config);

	connman_info("Adding configuration %s", config->ident);

	return config;
}

static int read_configs(void)
{
	GDir *dir;

	DBG("");

	dir = g_dir_open(STORAGEDIR, 0, NULL);
	if (dir != NULL) {
		const gchar *file;

		while ((file = g_dir_read_name(dir)) != NULL) {
			GString *str;
			gchar *ident;

			if (g_str_has_suffix(file, ".config") == FALSE)
				continue;

			ident = g_strrstr(file, ".config");
			if (ident == NULL)
				continue;

			str = g_string_new_len(file, ident - file);
			if (str == NULL)
				continue;

			ident = g_string_free(str, FALSE);

			if (connman_dbus_validate_ident(ident) == TRUE) {
				struct connman_config *config;

				config = create_config(ident);
				if (config != NULL)
					load_config(config);
			}
			g_free(ident);
		}

		g_dir_close(dir);
	}

	return 0;
}

static gboolean inotify_data(GIOChannel *channel, GIOCondition cond,
							gpointer user_data)
{
	char buffer[256];
	char *next_event;
	gsize bytes_read;
	GIOError err;

	if (cond & (G_IO_NVAL | G_IO_ERR | G_IO_HUP)) {
		inotify_watch = 0;
		return FALSE;
	}

	err = g_io_channel_read(channel, buffer,
					sizeof(buffer) - 1, &bytes_read);

	if (err != G_IO_ERROR_NONE) {
		if (err == G_IO_ERROR_AGAIN)
			return TRUE;

		connman_error("Reading from inotify channel failed");
		inotify_watch = 0;
		return FALSE;
	}

	next_event = buffer;

	while (bytes_read > 0) {
		struct inotify_event *event;
		gchar *ext;
		gchar *ident;
		gsize len;

		event = (struct inotify_event *) next_event;
		if (event->len)
			ident = next_event + sizeof(struct inotify_event);
		else
			ident = NULL;

		len = sizeof(struct inotify_event) + event->len;

		/* check if inotify_event block fit */
		if (len > bytes_read)
			break;

		next_event += len;
		bytes_read -= len;

		if (ident == NULL)
			continue;

		if (g_str_has_suffix(ident, ".config") == FALSE)
			continue;

		ext = g_strrstr(ident, ".config");
		if (ext == NULL)
			continue;

		*ext = '\0';

		if (connman_dbus_validate_ident(ident) == FALSE)
			continue;

		if (event->mask & IN_CREATE)
			create_config(ident);

		if (event->mask & IN_MODIFY) {
			struct connman_config *config;

			config = g_hash_table_lookup(config_table, ident);
			if (config != NULL) {
				g_hash_table_remove_all(config->service_table);
				load_config(config);
			}
		}

		if (event->mask & IN_DELETE)
			g_hash_table_remove(config_table, ident);
	}

	return TRUE;
}

static int create_watch(void)
{
	int fd;

	fd = inotify_init();
	if (fd < 0)
		return -EIO;

	inotify_wd = inotify_add_watch(fd, STORAGEDIR,
					IN_MODIFY | IN_CREATE | IN_DELETE);
	if (inotify_wd < 0) {
		connman_error("Creation of STORAGEDIR  watch failed");
		close(fd);
		return -EIO;
	}

	inotify_channel = g_io_channel_unix_new(fd);
	if (inotify_channel == NULL) {
		connman_error("Creation of inotify channel failed");
		inotify_rm_watch(fd, inotify_wd);
		inotify_wd = 0;

		close(fd);
		return -EIO;
	}

	g_io_channel_set_close_on_unref(inotify_channel, TRUE);
	g_io_channel_set_encoding(inotify_channel, NULL, NULL);
	g_io_channel_set_buffered(inotify_channel, FALSE);

	inotify_watch = g_io_add_watch(inotify_channel,
				G_IO_IN | G_IO_HUP | G_IO_NVAL | G_IO_ERR,
				inotify_data, NULL);

	return 0;
}

static void remove_watch(void)
{
	int fd;

	if (inotify_channel == NULL)
		return;

	if (inotify_watch > 0) {
		g_source_remove(inotify_watch);
		inotify_watch = 0;
	}

	fd = g_io_channel_unix_get_fd(inotify_channel);

	if (inotify_wd >= 0) {
		inotify_rm_watch(fd, inotify_wd);
		inotify_wd = 0;
	}

	g_io_channel_unref(inotify_channel);
}

int __connman_config_init(void)
{
	DBG("");

	config_table = g_hash_table_new_full(g_str_hash, g_str_equal,
						NULL, unregister_config);

	create_watch();

	return read_configs();
}

void __connman_config_cleanup(void)
{
	DBG("");

	remove_watch();

	g_hash_table_destroy(config_table);
	config_table = NULL;
}

static char *config_pem_fsid(const char *pem_file)
{
	struct statfs buf;
	unsigned *fsid = (unsigned *) &buf.f_fsid;
	unsigned long long fsid64;

	if (pem_file == NULL)
		return NULL;

	if (statfs(pem_file, &buf) < 0) {
		connman_error("statfs error %s for %s",
						strerror(errno), pem_file);
		return NULL;
	}

	fsid64 = ((unsigned long long) fsid[0] << 32) | fsid[1];

	return g_strdup_printf("%llx", fsid64);
}

static void provision_service(gpointer key, gpointer value, gpointer user_data)
{
	struct connman_service *service = user_data;
	struct connman_config_service *config = value;
	struct connman_network *network;
	const void *ssid;
	unsigned int ssid_len;

	/* For now only WiFi service entries are supported */
	if (g_strcmp0(config->type, "wifi") != 0)
		return;

	network = __connman_service_get_network(service);
	if (network == NULL) {
		connman_error("Service has no network set");
		return;
	}

	ssid = connman_network_get_blob(network, "WiFi.SSID", &ssid_len);
	if (ssid == NULL) {
		connman_error("Network SSID not set");
		return;
	}

	if (config->ssid == NULL || ssid_len != config->ssid_len)
		return;

	if (memcmp(config->ssid, ssid, ssid_len) != 0)
		return;

	__connman_service_set_immutable(service, TRUE);
	__connman_service_set_favorite(service, TRUE);

	if (config->eap != NULL)
		__connman_service_set_string(service, "EAP", config->eap);

	if (config->identity != NULL)
		__connman_service_set_string(service, "Identity",
							config->identity);

	if (config->ca_cert_file != NULL)
		__connman_service_set_string(service, "CACertFile",
							config->ca_cert_file);

	if (config->client_cert_file != NULL)
		__connman_service_set_string(service, "ClientCertFile",
						config->client_cert_file);

	if (config->private_key_file != NULL)
		__connman_service_set_string(service, "PrivateKeyFile",
						config->private_key_file);

	if (g_strcmp0(config->private_key_passphrase_type, "fsid") == 0 &&
					config->private_key_file != NULL) {
		char *fsid;

		fsid = config_pem_fsid(config->private_key_file);
		if (fsid == NULL)
			return;

		g_free(config->private_key_passphrase);
		config->private_key_passphrase = fsid;
	}

	if (config->private_key_passphrase != NULL) {
		__connman_service_set_string(service, "PrivateKeyPassphrase",
						config->private_key_passphrase);
		/*
		 * TODO: Support for PEAP with both identity and key passwd.
		 * In that case, we should check if both of them are found
		 * from the config file. If not, we should not set the
		 * service passphrase in order for the UI to request for an
		 * additional passphrase.
		 */
	}

	if (config->phase2 != NULL)
		__connman_service_set_string(service, "Phase2", config->phase2);

	if (config->passphrase != NULL)
		__connman_service_set_string(service, "Passphrase", config->passphrase);
}

int __connman_config_provision_service(struct connman_service *service)
{
	enum connman_service_type type;
	GHashTableIter iter;
	gpointer value, key;

	DBG("service %p", service);

	/* For now only WiFi services are supported */
	type = connman_service_get_type(service);
	if (type != CONNMAN_SERVICE_TYPE_WIFI)
		return -ENOSYS;

	g_hash_table_iter_init(&iter, config_table);

	while (g_hash_table_iter_next(&iter, &key, &value) == TRUE) {
		struct connman_config *config = value;

		g_hash_table_foreach(config->service_table,
						provision_service, service);
	}

	return 0;
}