libmobile.c

/**
 * TODO:
 *	1. Add more input options when creating APN profile
 *	2. Add DEBUG printout
 */
#include "libmobile.h"

struct string {
	char *ptr;
	size_t len;
};

enum {
	POST,
	GET
};

char *referer_url = "http://192.168.0.1/index.html";
char *base_url = "http://192.168.0.1/goform/goform_set_cmd_process";

static void curl_cleaner(CURLcode *curl);
static size_t write_func(void *buffer, size_t size, size_t nmemb, void *data);
static int apn_profile_idx(struct json_object *apn_profiles, char *name);
static int get_apn_profiles_len(void);
static char *lexer(char **input, char *delimiter);
static char *get_query_wrapper(char *vars);
static CURLcode perform_post_request(CURL *curl, char *query, struct string *str);
static CURLcode perform_get_request(CURL *curl, char *query, struct string *str);
static struct json_object *prepare_request(char *query, int option);
static struct json_object *parse_apn_profiles(struct json_object *apn_profiles);

/**
 * Function: curl_cleaner
 *
 * Free's the curl environment.
 *
 * Parameters:
 *		curl - The curl easy handle variable.
 */
static void curl_cleaner(CURLcode *curl)
{
	curl_easy_cleanup(curl);
	curl_global_cleanup();
}

/**
 * Function: write_func
 *
 * The callback function from performing the curl command, response from server will be reconstructed here.
 *
 * Parameters:
 *		buffer - Contains chunk of response from server.
 *		size - Size (byte) of type in buffer array.
 *		nmemb - Number of members in buffer.
 *		data - Pointer to area allocated for storing results from server.
 *
 * Returns:
 *		Number of bytes managed (size*nmemb).
 */
static size_t write_func(void *buffer, size_t size, size_t nmemb, void *data)
{
	struct string *str = (struct string *)data;
	size_t len = size * nmemb;
	size_t new_len = str->len + (len);
	char *tmp_ptr = str->ptr;

	str->ptr = realloc(str->ptr, new_len + 1);
	if (!str->ptr) {
		debug_print("not enough memory (realloc returned NULL)\n");
		free(tmp_ptr);
		return 0;
	}

	memcpy(str->ptr + str->len, buffer, len);
	str->ptr[new_len] = '\0';
	str->len = new_len;

	return len;
}

/**
 * Function: apn_profile_idx
 *
 * Finds the index of a given profile name from all available profiles.
 *
 * Parameters:
 *		apn_profiles - json_object pointer to apn_profiles (gotten from a previous call to <mobile_get_apn_profiles>)
 *		name - Name of the APN index for which will be searched.
 *
 * Returns:
 *		Index of the APN on success.
 *		-1 on failure.
 */
static int apn_profile_idx(struct json_object *apn_profiles, char *name)
{
	int idx = 0;

	json_object_object_foreach(apn_profiles, key, val) {
		struct json_object *profile_name_json;
		char *profile_name;

		json_object_object_get_ex(val, "profile_name", &profile_name_json);

		if (!profile_name_json)
			goto fail;
		profile_name = json_object_get_string(profile_name_json);

		if (strncmp(profile_name, name, 1024) == 0)
			return idx;
		idx++;
	}

fail:
	return -1;
}

/**
 * Function: get_apn_profiles_len
 *
 * Finds the number of APN profiles available.
 *
 * Returns:
 *		Number of APN profiles available on success.
 *		-1 on failure.
 */
static int get_apn_profiles_len(void)
{
	struct json_object *apn_profiles = mobile_get_apn_profiles();
	int len = 0;

	if (!apn_profiles) {
		debug_print("Failed to get apn profiles from server!\n");
		goto fail;
	}

	json_object_object_foreach(apn_profiles, key, val) {
		int val_type = json_object_get_type(val);

		if (val_type != json_type_string)
			len++;
		else
			goto success;
	}

success:
	json_object_put(apn_profiles);
	return len;
fail:
	return -1;
}

/**
 * Function: lexer
 *
 * Take an input string and a delimiter which to split the string on. Returns all characters
 * prior to the delimiter, and removes it from the input string.
 *
 * Parameters:
 *		input - A character pointer address to the pointer pointing at the string to split.
 *		delimiter - A character pointer pointing to the delimiter on which to split the string on.
 *
 * Returns:
 *		A character pointer to the tokens prior to the delimiter on success.
 *		NULL on failure, missing input, delimiter or when no delimiter is present.
 *
 * IMPORTANT NOTE
 *		Will alter the input string and allocate memory for the return value!
 * 		The caller is responsible for freeing the return value.
 */
static char *lexer(char **input, char *delimiter)
{
	char *token, *substr;

	if (strlen(*input) == 0) {
		debug_print("empty input!\n");
		return NULL;
	} else if (strlen(delimiter) == 0) {
		debug_print("empty delimiter!\n");
		return NULL;
	}

	token = strstr(*input, delimiter);

	if (token)
		*token = '\0';
	else
		return NULL;

	substr = strdup(*input);
	*input = token + strlen(delimiter);

	return substr;
}

/**
 * Function: get_query_wrapper
 * 		Wraps the input comma-separated values to the appropriate address format for a GET request.
 *
 * Parameters:
 *		vars - Char pointer pointing to comma-separated values to retreive.
 *
 * Returns:
 *		The entire query on success.
 *		NULL on failure.
 */
static char *get_query_wrapper(char *vars)
{
	char query[1024] = {0};

	if (strlen(vars) == 0) {
		debug_print("No GET input provided!\n");
		return NULL;
	}
	snprintf(query, 1023, "http://192.168.0.1/goform/goform_get_cmd_process?isTest=false&cmd=%s&multi_data=1", vars);
	debug_print("query %s\n", query);
	return strdup(query);
}

/**
 * Function: perform_post_request
 *
 * Executes a prepared HTTP POST query through use of the libcurl lbirary.
 *
 * Parameter:
 *		curl - the CURL environment.
 *		query - The HTTP POST query to execute.
 *		str - a string struct containing the current data pointer and the length of the data currently written.
 *
 * Returns:
 *		The CURLcode indicating the success or failure of the curl execution.
 */
static CURLcode perform_post_request(CURL *curl, char *query, struct string *str)
{
	curl_easy_setopt(curl, CURLOPT_URL, "http://192.168.0.1/goform/goform_set_cmd_process");
	//curl_easy_setopt(curl, CURLOPT_URL, base_url); //why doesn't this work?
	curl_easy_setopt(curl, CURLOPT_REFERER, referer_url);
	curl_easy_setopt(curl, CURLOPT_POSTFIELDS, query);
	curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_func);
	curl_easy_setopt(curl, CURLOPT_WRITEDATA, str);

	return curl_easy_perform(curl);
}

/**
 * Function: perform_get_request
 *
 * Executes a prepared HTTP GET query through use of the libcurl lbirary.
 *
 * Parameter:
 *		curl - the CURL environment.
 *		query - The HTTP GET query to execute.
 *		str - a string struct containing the current data pointer and the length of the data currently written.
 *
 * Returns:
 *		The CURLcode indicating the success or failure of the curl execution.
 */
static CURLcode perform_get_request(CURL *curl, char *query, struct string *str)
{
	curl_easy_setopt(curl, CURLOPT_URL, query);
	curl_easy_setopt(curl, CURLOPT_REFERER, referer_url);
	curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_func);
	curl_easy_setopt(curl, CURLOPT_WRITEDATA, str);

	return curl_easy_perform(curl);
}

/**
 * Function: send_post_request
 *
 * Function that prepares curl environment and final POST query, then executes said query.
 *
 * Parameter:
 *		query - The POST query content to execute.
 *
 * Returns:
 *		A pointer to a json_object containing the JSON response from the server.
 *		NULL on failure.
 */
static struct json_object *prepare_request(char *query, int option)
{
	CURL *curl;
	CURLcode rv;
	struct string str = {NULL, 0};
	struct json_object *parsed_response;

	str.ptr = calloc(1, 1);
	if (!str.ptr) {
		debug_print("Error allocating memory with calloc");
		goto fail;
	}

	curl = curl_easy_init();
	if (!curl) {
		debug_print("Failed to prepare curl environment!\n");
		goto fail_curl;
	}

	if (option == POST)
		rv = perform_post_request(curl, query, &str);
	else if (option == GET) {
		query = get_query_wrapper(query);
		rv = perform_get_request(curl, query, &str);
	}

	if (rv) {
		debug_print("error performing curl, %s\n", curl_easy_strerror(rv));
		goto fail;
	}
	if (!str.ptr)
		goto fail_ptr;

	debug_print("%s\n", str.ptr);
	parsed_response = json_tokener_parse(str.ptr);
	if (!parsed_response) {
		debug_print("No valid JSON, failed parsing!\n");
		goto fail_json;
	}

	free(query);
	curl_cleaner(curl);
	free(str.ptr);
	return parsed_response;
fail_json:
fail_ptr:
	curl_cleaner(curl);
fail_curl:
	free(str.ptr);
fail:
	free(query);
	return NULL;
}

/**
 * Function: parse_apn_profiles
 *
 * Takes a string of APN profile configurations provided by zte-mf823 (which is in an awkward, difficult to read format)
 * and transforms them into a more easily read and worked with JSON format.
 *
 * Parameters:
 *		apn_profiles - A json_object pointer containing the original apn configuration returned by the dongle.
 *
 * Returns:
 *		A json_object pointer to apn configurations in a more representative and easier to use format.
 *		NULL on failure.
 */

static struct json_object *parse_apn_profiles(struct json_object *apn_profiles)
{
	struct json_object *parsed_profiles = json_object_new_object();
	int apn_counter = 0;
	char *field_names[13] = {"profile_name", "apn_name", "mode", "wan_dial", "ppp_auth_mode", "ppp_username", "ppp_passwd", "pdp", "pdpd_select", "pdp_addr", "dns_mode", "prefer_dns_manual", "standby_dns_manual"};

	json_object_object_foreach(apn_profiles, key, val) {
		char *apn_string = json_object_get_string(val);
		int i = 0;
		struct json_object *apn_profile = json_object_new_object();
		char *field_val;
		char name[1024] = {0};

		if (strlen(apn_string) <= 0)
			goto finished;
		while ((field_val = lexer(&apn_string, "($)")) != NULL) {
			json_object_object_add(apn_profile, field_names[i], json_object_new_string(field_val));
			i++;
			free(field_val);
		}
		snprintf(name, 1023, "apn_config_%d", apn_counter);

		json_object_object_add(parsed_profiles, name, json_object_get(apn_profile));
		json_object_put(apn_profile);
		apn_counter++;
	}

finished:
	json_object_put(apn_profiles);
	return parsed_profiles;
}


struct json_object *mobile_connect_network(void)
{
	return prepare_request("isTest=false&goformId=CONNECT_NETWORK", POST);
}

struct json_object *mobile_disconnect_network(void)
{
	return prepare_request("isTest=false&goformId=DISCONNECT_NETWORK", POST);
}

struct json_object *mobile_delete_apn(char *name)
{
	struct json_object *apn_profiles = mobile_get_apn_profiles();
	char query[1024] = {0};
	int idx;

	if (!apn_profiles) {
		debug_print("no response!\n");
		goto fail;
	}
	idx = apn_profile_idx(apn_profiles, name);
	if (idx < 0) {
		debug_print("APN not found in list!\n");
		goto fail_idx;
	}

	snprintf(query, 1023, "isTest=false&apn_action=delete&apn_mode=manual&index=%d&goformId=APN_PROC_EX", idx);
	json_object_put(apn_profiles);
	return prepare_request(query, POST);

fail_idx:
	json_object_put(apn_profiles);
fail:
	return NULL;
}

struct json_object *mobile_enable_roaming(void)
{
	return prepare_request("isTest=false&goformId=SET_CONNECTION_MODE&roam_setting_option=on", POST);
}

struct json_object *mobile_disable_roaming(void)
{
	return prepare_request("isTest=false&goformId=SET_CONNECTION_MODE&roam_setting_option=off", POST);
}

struct json_object *mobile_get_roam_status(void)
{
	return prepare_request("roam_setting_option", GET);
}

struct json_object *mobile_get_wan_apn(void)
{
	return prepare_request("wan_apn", GET);
}

struct json_object *mobile_get_remaining_tries(void)
{
	return prepare_request("pinnumber", GET);
}

struct json_object *mobile_get_pin_status(void)
{
	return prepare_request("pin_status", GET);
}

struct json_object *mobile_get_rssi(void)
{
	return prepare_request("rssi", GET);
}

struct json_object *mobile_get_modem_state(void)
{
	return prepare_request("&sms_received_flag_flag=0&sts_received_flag_flag=0&cmd=modem_main_state%2Cpin_status%2Cloginfo%2Cnew_version_state%2Ccurrent_upgrade_state%2Cis_mandatory%2Csms_received_flag%2Csts_received_flag%2Csignalbar%2Cnetwork_type%2Cnetwork_provider%2Cppp_status%2CEX_SSID1%2Cex_wifi_status%2CEX_wifi_profile%2Cm_ssid_enable%2Csms_unread_num%2CRadioOff%2Csimcard_roam%2Clan_ipaddr%2Cstation_mac%2Cbattery_charging%2Cbattery_vol_percent%2Cbattery_pers%2Cspn_display_flag%2Cplmn_display_flag%2Cspn_name_data%2Cspn_b1_flag%2Cspn_b2_flag%2Crealtime_tx_bytes%2Crealtime_rx_bytes%2Crealtime_time%2Crealtime_tx_thrpt%2Crealtime_rx_thrpt%2Cmonthly_rx_bytes%2Cmonthly_tx_bytes%2Cmonthly_time%2Cdate_month%2Cdata_volume_limit_switch%2Cdata_volume_limit_size%2Cdata_volume_alert_percent%2Cdata_volume_limit_unit%2Croam_setting_option%2Cupg_roam_switch%2Chplmn", GET);
}

struct json_object *mobile_get_apn_profiles(void)
{
	struct json_object *apn_profiles = prepare_request("APN_config0,APN_config1,APN_config2,APN_config3,APN_config4,APN_config5,APN_config6,APN_config7,APN_config8,APN_config9,APN_config10,APN_config11,APN_config12,APN_config13,APN_config14,APN_config15,APN_config16,APN_config17,APN_config18,APN_config19", GET);

	if (!apn_profiles) {
		debug_print("Error getting profiles!\n");
		goto fail;
	}
	return parse_apn_profiles(apn_profiles);
fail:
	return NULL;
}

struct json_object *mobile_create_apn_profile(char *profile_name, char *wan_apn, char *pdp_type)
{
	char query[1024] = {0};

	snprintf(query, 1023, "isTest=false&goformId=APN_PROC_EX&apn_action=save&apn_mode=manual&profile_name=%s&wan_dial=*99%23&apn_select=manual&pdp_type=%s&pdp_select=auto&pdp_addr=&index=%d&wan_apn=%s&ppp_auth_mode=none&ppp_username=&ppp_passwd=&dns_mode=auto&prefer_dns_manual=&standby_dns_manual=", profile_name, pdp_type, get_apn_profiles_len(), wan_apn);

	return prepare_request(query, POST);
}

struct json_object *mobile_set_apn_profile(char *name)
{
	struct json_object *apn_profiles = mobile_get_apn_profiles();
	int idx;
	char query[1024] = {0};

	if (!apn_profiles) {
		debug_print("no response!\n");
		goto fail;
	}
	idx = apn_profile_idx(apn_profiles, name);

	if (idx < 0) {
		debug_print("couldnt find idx, no such profile!\n");
		goto free_idx;
	}
	snprintf(query, 1023, "isTest=false&goformId=APN_PROC_EX&apn_mode=manual&apn_action=set_default&set_default_flag=1&pdp_type=IP&index=%d", idx);

	json_object_put(apn_profiles);
	return prepare_request(query, POST);
free_idx:
	json_object_put(apn_profiles);
fail:
	return NULL;
}

struct json_object *mobile_enable_pin(char *pin)
{
	char query[1024] = {0};

	snprintf(query, 1023, "isTest=false&goformId=ENABLE_PIN&OldPinNumber=%s&pin_save_flag=0&isTest=false", pin);

	return prepare_request(query, POST);
}

struct json_object *mobile_set_pin(char *current_pin, char *new_pin)
{
	char query[1024] = {0};

	snprintf(query, 1023, "isTest=false&goformId=ENABLE_PIN&OldPinNumber=%s&NewPinNumber=%s&pin_save_flag=0&isTest=false", current_pin, new_pin);

	return prepare_request(query, POST);
}

struct json_object *mobile_disable_pin(char *pin)
{
	char query[1024] = {0};

	snprintf(query, 1023, "isTest=false&goformId=DISABLE_PIN&OldPinNumber=%s&pin_save_flag=0&isTest=false", pin);

	return prepare_request(query, POST);
}