rmnetctl/src/librmnetctl.c

/******************************************************************************

			L I B R M N E T C T L . C

Copyright (c) 2013, The Linux Foundation. All rights reserved.

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modification, are permitted provided that the following conditions are
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	  notice, this list of conditions and the following disclaimer.
	* Redistributions in binary form must reproduce the above
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******************************************************************************/

/*!
* @file    librmnetctl.c
* @brief   rmnet control API's implentations file
*/

/*===========================================================================
			INCLUDE FILES
===========================================================================*/

#include <sys/socket.h>
#include <stdint.h>
#include <linux/netlink.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <linux/rmnet_data.h>
#include "librmnetctl_hndl.h"
#include "librmnetctl.h"

#define RMNETCTL_SOCK_FLAG 0
#define ROOT_USER_ID 0
#define MIN_VALID_PROCESS_ID 0
#define MIN_VALID_SOCKET_FD 0
#define KERNEL_PROCESS_ID 0
#define UNICAST 0
#define MAX_BUF_SIZE sizeof(struct nlmsghdr) + sizeof(struct rmnet_nl_msg_s)

/*===========================================================================
			LOCAL FUNCTION DEFINITIONS
===========================================================================*/
/*!
* @brief Synchronous method to send and receive messages to and from the kernel
* using  netlink sockets
* @details Increments the transaction id for each message sent to the kernel.
* Sends the netlink message to the kernel and receives the response from the
* kernel.
* @param *hndl RmNet handle for this transaction
* @param request Message to be sent to the kernel
* @param response Message received from the kernel
* @return RMNETCTL_API_SUCCESS if successfully able to send and receive message
* from the kernel
* @return RMNETCTL_API_ERR_HNDL_INVALID if RmNet handle for the transaction was
* NULL
* @return RMNETCTL_API_ERR_REQUEST_NULL not enough memory to create buffer for
* sending the message
* @return RMNETCTL_API_ERR_MESSAGE_SEND if could not send the message to kernel
* @return RMNETCTL_API_ERR_MESSAGE_RECEIVE if could not receive message from the
* kernel
* @return RMNETCTL_API_ERR_MESSAGE_TYPE if the request and response type do not
* match
*/
static int rmnetctl_transact(rmnetctl_hndl_t *hndl,
			struct rmnet_nl_msg_s *request,
			struct rmnet_nl_msg_s *response) {
	uint8_t *request_buf, *response_buf;
	struct nlmsghdr *nlmsghdr_val;
	struct rmnet_nl_msg_s *rmnet_nl_msg_s_val;
	int bytes_read = -1, return_code = RMNETCTL_API_ERR_HNDL_INVALID;
	request_buf = NULL;
	response_buf = NULL;
	nlmsghdr_val = NULL;
	rmnet_nl_msg_s_val = NULL;
	do {
	if (!hndl){
		break;
	}
	if (!request){
		return_code = RMNETCTL_API_ERR_REQUEST_NULL;
		break;
	}
	if (!response){
		return_code = RMNETCTL_API_ERR_RESPONSE_NULL;
		break;
	}
	request_buf = (uint8_t *)malloc(MAX_BUF_SIZE * sizeof(uint8_t));
	if (!request_buf){
		return_code = RMNETCTL_API_ERR_REQUEST_NULL;
		break;
	}

	response_buf = (uint8_t *)malloc(MAX_BUF_SIZE * sizeof(uint8_t));
	if (!response_buf) {
		free(request_buf);
		return_code = RMNETCTL_API_ERR_RESPONSE_NULL;
		break;
	}

	nlmsghdr_val = (struct nlmsghdr *)request_buf;
	rmnet_nl_msg_s_val = (struct rmnet_nl_msg_s *)NLMSG_DATA(request_buf);

	memset(request_buf, 0, MAX_BUF_SIZE*sizeof(uint8_t));
	memset(response_buf, 0, MAX_BUF_SIZE*sizeof(uint8_t));

	nlmsghdr_val->nlmsg_seq = hndl->transaction_id;
	nlmsghdr_val->nlmsg_pid = hndl->pid;
	nlmsghdr_val->nlmsg_len = MAX_BUF_SIZE;

	memcpy((void *)NLMSG_DATA(request_buf), request,
	sizeof(struct rmnet_nl_msg_s));

	rmnet_nl_msg_s_val->crd = RMNET_NETLINK_MSG_COMMAND;
	hndl->transaction_id++;

	socklen_t addrlen = sizeof(struct sockaddr_nl);
	if (sendto(hndl->netlink_fd,
			request_buf,
			MAX_BUF_SIZE,
			RMNETCTL_SOCK_FLAG,
			(struct sockaddr *) &hndl->dest_addr,
			sizeof(struct sockaddr_nl)) < 0) {
		return_code = RMNETCTL_API_ERR_MESSAGE_SEND;
		free(request_buf);
		free(response_buf);
		break;
	}

	bytes_read = recvfrom(hndl->netlink_fd,
			response_buf,
			MAX_BUF_SIZE,
			RMNETCTL_SOCK_FLAG,
			(struct sockaddr *) &hndl->src_addr,
			&addrlen);
	if (bytes_read < 0) {
		return_code = RMNETCTL_API_ERR_MESSAGE_RECEIVE;
		free(request_buf);
		free(response_buf);
		break;
	}

	memcpy(response, (void *)NLMSG_DATA(response_buf),
	sizeof(struct rmnet_nl_msg_s));
	if (sizeof(*response) < sizeof(struct rmnet_nl_msg_s)) {
		return_code = RMNETCTL_API_ERR_RESPONSE_NULL;
		free(request_buf);
		free(response_buf);
		break;
	}

	if (request->message_type != response->message_type) {
		return_code = RMNETCTL_API_ERR_MESSAGE_TYPE;
		free(request_buf);
		free(response_buf);
		break;
	}
	return_code = RMNETCTL_SUCCESS;
	} while(0);
	return return_code;
}

/*!
* @brief Static function to check the dev name
* @details Checks if the name is not NULL and if the name is less than the
* RMNET_MAX_STR_LEN
* @param dev_name Name of the device
* @return RMNETCTL_SUCCESS if successful
* @return RMNETCTL_INVALID_ARG if invalid arguments were passed to the API
*/
static inline int _rmnetctl_check_dev_name(const char *dev_name) {
	int return_code = RMNETCTL_INVALID_ARG;
	do {
	if (!dev_name)
		break;
	if (strlen(dev_name) >= RMNET_MAX_STR_LEN)
		break;
	return_code = RMNETCTL_SUCCESS;
	} while(0);
	return return_code;
}

/*!
* @brief Static function to check the string length after a copy
* @details Checks if the string length is not lesser than zero and lesser than
* RMNET_MAX_STR_LEN
* @param str_len length of the string after a copy
* @param error_code Status code of this operation
* @return RMNETCTL_SUCCESS if successful
* @return RMNETCTL_LIB_ERR if there was a library error. Check error_code
*/
static inline int _rmnetctl_check_len(int str_len, uint16_t *error_code) {
	int return_code = RMNETCTL_LIB_ERR;
	do {
	if ((str_len < 0) || (str_len > RMNET_MAX_STR_LEN)) {
		*error_code = RMNETCTL_API_ERR_STRING_TRUNCATION;
		break;
	}
	return_code = RMNETCTL_SUCCESS;
	} while(0);
	return return_code;
}

/*!
* @brief Static function to check the response type
* @details Checks if the response type of this message was return code
* @param crd The crd field passed
* @param error_code Status code of this operation
* @return RMNETCTL_SUCCESS if successful
* @return RMNETCTL_LIB_ERR if there was a library error. Check error_code
*/
static inline int _rmnetctl_check_code(int crd, uint16_t *error_code) {
	int return_code = RMNETCTL_LIB_ERR;
	do {
	if (crd != RMNET_NETLINK_MSG_RETURNCODE) {
		*error_code = RMNETCTL_API_ERR_RETURN_TYPE;
		break;
	}
	return_code = RMNETCTL_SUCCESS;
	} while(0);
	return return_code;
}

/*!
* @brief Static function to check the response type
* @details Checks if the response type of this message was data
* @param crd The crd field passed
* @param error_code Status code of this operation
* @return RMNETCTL_SUCCESS if successful
* @return RMNETCTL_LIB_ERR if there was a library error. Check error_code
*/
static inline int _rmnetctl_check_data(int crd, uint16_t *error_code) {
	int return_code = RMNETCTL_LIB_ERR;
	do {
	if (crd != RMNET_NETLINK_MSG_RETURNDATA) {
		*error_code = RMNETCTL_API_ERR_RETURN_TYPE;
		break;
	}
	return_code = RMNETCTL_SUCCESS;
	} while(0);
	return return_code;
}

/*!
* @brief Static function to set the return value
* @details Checks if the error_code from the transaction is zero for a return
* code type message and sets the message type as RMNETCTL_SUCCESS
* @param crd The crd field passed
* @param error_code Status code of this operation
* @return RMNETCTL_SUCCESS if successful
* @return RMNETCTL_KERNEL_ERR if there was an error in the kernel.
* Check error_code
*/
static inline int _rmnetctl_set_codes(int error_val, uint16_t *error_code) {
	int return_code = RMNETCTL_KERNEL_ERR;
	*error_code = error_val;
	if (*error_code == RMNETCTL_SUCCESS)
		return_code = RMNETCTL_SUCCESS;
	return return_code;
}

/*===========================================================================
				EXPOSED API
===========================================================================*/

int rmnetctl_init(rmnetctl_hndl_t **hndl, uint16_t *error_code)
{
	int pid = -1, netlink_fd = -1, return_code = RMNETCTL_LIB_ERR;
	do {
	if ((!hndl) || (!error_code)){
		return_code = RMNETCTL_INVALID_ARG;
		break;
	}

	*hndl = (rmnetctl_hndl_t *)malloc(sizeof(rmnetctl_hndl_t));
	if (!*hndl) {
		*error_code = RMNETCTL_API_ERR_HNDL_INVALID;
		break;
	}

	memset(*hndl, 0, sizeof(rmnetctl_hndl_t));

	pid = getpid();
	if (pid  < MIN_VALID_PROCESS_ID) {
		free(*hndl);
		*error_code = RMNETCTL_INIT_ERR_PROCESS_ID;
		break;
	}
	(*hndl)->pid = pid;
	netlink_fd = socket(PF_NETLINK, SOCK_RAW, RMNET_NETLINK_PROTO);
	if (netlink_fd < MIN_VALID_SOCKET_FD) {
		free(*hndl);
		*error_code = RMNETCTL_INIT_ERR_NETLINK_FD;
		break;
	}

	(*hndl)->netlink_fd = netlink_fd;

	memset(&(*hndl)->src_addr, 0, sizeof(struct sockaddr_nl));

	(*hndl)->src_addr.nl_family = AF_NETLINK;
	(*hndl)->src_addr.nl_pid = (*hndl)->pid;

	if (bind((*hndl)->netlink_fd,
		(struct sockaddr *)&(*hndl)->src_addr,
		sizeof(struct sockaddr_nl)) < 0) {
		close((*hndl)->netlink_fd);
		free(*hndl);
		*error_code = RMNETCTL_INIT_ERR_BIND;
		break;
	}

	memset(&(*hndl)->dest_addr, 0, sizeof(struct sockaddr_nl));

	(*hndl)->dest_addr.nl_family = AF_NETLINK;
	(*hndl)->dest_addr.nl_pid = KERNEL_PROCESS_ID;
	(*hndl)->dest_addr.nl_groups = UNICAST;

	return_code = RMNETCTL_SUCCESS;
	} while(0);
	return return_code;
}

void rmnetctl_cleanup(rmnetctl_hndl_t *hndl)
{
	if (!hndl)
		return;
	close(hndl->netlink_fd);
	free(hndl);
}

int rmnet_associate_network_device(rmnetctl_hndl_t *hndl,
				   const char *dev_name,
				   uint16_t *error_code,
				   uint8_t assoc_dev)
{
	struct rmnet_nl_msg_s request, response;
	int str_len = -1, return_code = RMNETCTL_LIB_ERR;
	do {
	if ((!hndl) || (!error_code) || _rmnetctl_check_dev_name(dev_name) ||
		((assoc_dev != RMNETCTL_DEVICE_ASSOCIATE) &&
		(assoc_dev != RMNETCTL_DEVICE_UNASSOCIATE))) {
		return_code = RMNETCTL_INVALID_ARG;
		break;
	}

	if (assoc_dev == RMNETCTL_DEVICE_ASSOCIATE)
		request.message_type = RMNET_NETLINK_ASSOCIATE_NETWORK_DEVICE;
	else
		request.message_type = RMNET_NETLINK_UNASSOCIATE_NETWORK_DEVICE;

	request.arg_length = RMNET_MAX_STR_LEN;
	str_len = strlcpy((char *)(request.data), dev_name, RMNET_MAX_STR_LEN);
	if (_rmnetctl_check_len(str_len, error_code) != RMNETCTL_SUCCESS)
		break;

	if ((*error_code = rmnetctl_transact(hndl, &request, &response))
		!= RMNETCTL_SUCCESS)
		break;
	if (_rmnetctl_check_code(response.crd, error_code) != RMNETCTL_SUCCESS)
		break;
	return_code = _rmnetctl_set_codes(response.return_code, error_code);
	} while(0);
	return return_code;
}

int rmnet_get_network_device_associated(rmnetctl_hndl_t *hndl,
					const char *dev_name,
					int *register_status,
					uint16_t *error_code) {
	struct rmnet_nl_msg_s request, response;
	int str_len = -1, return_code = RMNETCTL_LIB_ERR;
	do {
	if ((!hndl) || (!register_status) || (!error_code) ||
	_rmnetctl_check_dev_name(dev_name)) {
		return_code = RMNETCTL_INVALID_ARG;
		break;
	}

	request.message_type = RMNET_NETLINK_GET_NETWORK_DEVICE_ASSOCIATED;

	request.arg_length = RMNET_MAX_STR_LEN;
	str_len = strlcpy((char *)(request.data), dev_name, RMNET_MAX_STR_LEN);
	if (_rmnetctl_check_len(str_len, error_code) != RMNETCTL_SUCCESS)
		break;

	if ((*error_code = rmnetctl_transact(hndl, &request, &response))
		!= RMNETCTL_SUCCESS)
		break;

	if (_rmnetctl_check_data(response.crd, error_code) != RMNETCTL_SUCCESS)
		break;

	*register_status = response.return_code;
	return_code = RMNETCTL_SUCCESS;
	} while(0);
	return return_code;
}

int rmnet_set_link_egress_data_format(rmnetctl_hndl_t *hndl,
				      uint32_t egress_flags,
				      uint16_t agg_size,
				      uint16_t agg_count,
				      const char *dev_name,
				      uint16_t *error_code) {
	struct rmnet_nl_msg_s request, response;
	int str_len = -1, return_code = RMNETCTL_LIB_ERR;
	do {
	if ((!hndl) || (!error_code) || _rmnetctl_check_dev_name(dev_name)) {
		return_code = RMNETCTL_INVALID_ARG;
		break;
	}

	request.message_type = RMNET_NETLINK_SET_LINK_EGRESS_DATA_FORMAT;

	request.arg_length = RMNET_MAX_STR_LEN +
			 sizeof(uint32_t) + sizeof(uint16_t) + sizeof(uint16_t);
	str_len = strlcpy((char *)(request.data_format.dev),
			  dev_name,
			  RMNET_MAX_STR_LEN);
	if (_rmnetctl_check_len(str_len, error_code) != RMNETCTL_SUCCESS)
		break;

	request.data_format.flags = egress_flags;
	request.data_format.agg_size = agg_size;
	request.data_format.agg_count = agg_count;

	if ((*error_code = rmnetctl_transact(hndl, &request, &response))
		!= RMNETCTL_SUCCESS)
		break;

	if (_rmnetctl_check_code(response.crd, error_code) != RMNETCTL_SUCCESS)
		break;

	return_code = _rmnetctl_set_codes(response.return_code, error_code);
	} while(0);
	return return_code;
}

int rmnet_get_link_egress_data_format(rmnetctl_hndl_t *hndl,
				      const char *dev_name,
				      uint32_t *egress_flags,
				      uint16_t *agg_size,
				      uint16_t *agg_count,
				      uint16_t *error_code) {
	struct rmnet_nl_msg_s request, response;
	int str_len = -1, return_code = RMNETCTL_LIB_ERR;
	do {
	if ((!hndl) || (!egress_flags) || (!agg_size) || (!agg_count) ||
	(!error_code) || _rmnetctl_check_dev_name(dev_name)) {
		return_code = RMNETCTL_INVALID_ARG;
		break;
	}
	request.message_type = RMNET_NETLINK_GET_LINK_EGRESS_DATA_FORMAT;

	request.arg_length = RMNET_MAX_STR_LEN;
	str_len = strlcpy((char *)(request.data_format.dev),
			  dev_name,
			  RMNET_MAX_STR_LEN);
	if (_rmnetctl_check_len(str_len, error_code) != RMNETCTL_SUCCESS)
		break;

	if ((*error_code = rmnetctl_transact(hndl, &request, &response))
		!= RMNETCTL_SUCCESS)
		break;

	if (_rmnetctl_check_data(response.crd, error_code) != RMNETCTL_SUCCESS)
		break;

	*egress_flags = response.data_format.flags;
	*agg_size = response.data_format.agg_size;
	*agg_count = response.data_format.agg_count;
	return_code = RMNETCTL_SUCCESS;
	} while(0);
	return return_code;
}

int rmnet_set_link_ingress_data_format(rmnetctl_hndl_t *hndl,
				       uint32_t ingress_flags,
				       const char *dev_name,
				       uint16_t *error_code) {
	struct rmnet_nl_msg_s request, response;
	int str_len = -1, return_code = RMNETCTL_LIB_ERR;
	do {
	if ((!hndl) || (!error_code) || _rmnetctl_check_dev_name(dev_name)) {
		return_code = RMNETCTL_INVALID_ARG;
		break;
	}

	request.message_type = RMNET_NETLINK_SET_LINK_INGRESS_DATA_FORMAT;

	request.arg_length = RMNET_MAX_STR_LEN +
	sizeof(uint32_t) + sizeof(uint16_t) + sizeof(uint16_t);
	str_len = strlcpy((char *)(request.data_format.dev),
			  dev_name,
			  RMNET_MAX_STR_LEN);
	if (_rmnetctl_check_len(str_len, error_code) != RMNETCTL_SUCCESS)
		break;
	request.data_format.flags = ingress_flags;

	if ((*error_code = rmnetctl_transact(hndl, &request, &response))
		!= RMNETCTL_SUCCESS)
		break;

	if (_rmnetctl_check_code(response.crd, error_code) != RMNETCTL_SUCCESS)
		break;

	return_code = _rmnetctl_set_codes(response.return_code, error_code);
	} while(0);
	return return_code;
}

int rmnet_get_link_ingress_data_format(rmnetctl_hndl_t *hndl,
				       const char *dev_name,
				       uint32_t *ingress_flags,
				       uint16_t *error_code) {
	struct rmnet_nl_msg_s request, response;
	int str_len = -1, return_code = RMNETCTL_LIB_ERR;
	do {
	if ((!hndl) || (!ingress_flags) || (!error_code) ||
		_rmnetctl_check_dev_name(dev_name)) {
		return_code = RMNETCTL_INVALID_ARG;
		break;
	}

	request.message_type = RMNET_NETLINK_GET_LINK_INGRESS_DATA_FORMAT;

	request.arg_length = RMNET_MAX_STR_LEN;
	str_len = strlcpy((char *)(request.data_format.dev),
			  dev_name,
			  RMNET_MAX_STR_LEN);
	if (_rmnetctl_check_len(str_len, error_code) != RMNETCTL_SUCCESS)
		break;

	if ((*error_code = rmnetctl_transact(hndl, &request, &response))
		!= RMNETCTL_SUCCESS)
		break;

	if (_rmnetctl_check_data(response.crd, error_code) != RMNETCTL_SUCCESS)
		break;

	*ingress_flags = response.data_format.flags;
	return_code = RMNETCTL_SUCCESS;
	} while(0);
	return return_code;
}

int rmnet_set_logical_ep_config(rmnetctl_hndl_t *hndl,
				int32_t ep_id,
				uint8_t operating_mode,
				const char *dev_name,
				const char *next_dev,
				uint16_t *error_code) {
	struct rmnet_nl_msg_s request, response;
	int str_len = -1, return_code = RMNETCTL_LIB_ERR;
	do {
	if ((!hndl) || ((ep_id < -1) || (ep_id > 31)) || (!error_code) ||
		_rmnetctl_check_dev_name(dev_name) ||
		_rmnetctl_check_dev_name(next_dev)) {
		return_code = RMNETCTL_INVALID_ARG;
		break;
	}

	request.message_type = RMNET_NETLINK_SET_LOGICAL_EP_CONFIG;

	request.arg_length = RMNET_MAX_STR_LEN +
	RMNET_MAX_STR_LEN + sizeof(int32_t) + sizeof(uint8_t);
	str_len = strlcpy((char *)(request.local_ep_config.dev),
			  dev_name,
			  RMNET_MAX_STR_LEN);
	if (_rmnetctl_check_len(str_len, error_code) != RMNETCTL_SUCCESS)
		break;

	str_len = strlcpy((char *)(request.local_ep_config.next_dev),
			  next_dev,
			  RMNET_MAX_STR_LEN);
	if (_rmnetctl_check_len(str_len, error_code) != RMNETCTL_SUCCESS)
		break;
	request.local_ep_config.ep_id = ep_id;
	request.local_ep_config.operating_mode = operating_mode;

	if ((*error_code = rmnetctl_transact(hndl, &request, &response))
		!= RMNETCTL_SUCCESS)
		break;
	if (_rmnetctl_check_code(response.crd, error_code) != RMNETCTL_SUCCESS)
		break;

	return_code = _rmnetctl_set_codes(response.return_code, error_code);
	} while(0);
	return return_code;
}

int rmnet_get_logical_ep_config(rmnetctl_hndl_t *hndl,
				int32_t ep_id,
				const char *dev_name,
				uint8_t *operating_mode,
				char **next_dev,
				uint16_t *error_code) {
	struct rmnet_nl_msg_s request, response;
	int str_len = -1, return_code = RMNETCTL_LIB_ERR;
	do {
	if ((!hndl) || (!operating_mode) || (!error_code) || ((ep_id < -1) ||
	(ep_id > 31)) || _rmnetctl_check_dev_name(dev_name) || (!next_dev)) {
		return_code = RMNETCTL_INVALID_ARG;
		break;
	}

	request.message_type = RMNET_NETLINK_GET_LOGICAL_EP_CONFIG;

	request.arg_length = RMNET_MAX_STR_LEN + sizeof(int32_t);
	str_len = strlcpy((char *)(request.local_ep_config.dev),
			  dev_name,
			  RMNET_MAX_STR_LEN);
	if (_rmnetctl_check_len(str_len, error_code) != RMNETCTL_SUCCESS)
		break;

	request.local_ep_config.ep_id = ep_id;

	if ((*error_code = rmnetctl_transact(hndl, &request, &response))
		!= RMNETCTL_SUCCESS)
		break;
	if (_rmnetctl_check_data(response.crd, error_code) != RMNETCTL_SUCCESS)
		break;
	printf("%s\n", (char *)(response.local_ep_config.next_dev));
	str_len = strlcpy(*next_dev,
			  (char *)(response.local_ep_config.next_dev),
			  RMNET_MAX_STR_LEN);
	if (_rmnetctl_check_len(str_len, error_code) != RMNETCTL_SUCCESS)
		break;

	*operating_mode = response.local_ep_config.operating_mode;
	return_code = RMNETCTL_SUCCESS;
	} while(0);
	return return_code;
}

int rmnet_new_vnd(rmnetctl_hndl_t *hndl,
		  uint32_t id,
		  uint16_t *error_code,
		  uint8_t new_vnd) {
	struct rmnet_nl_msg_s request, response;
	int return_code = RMNETCTL_LIB_ERR;
	do {
	if ((!hndl) || (!error_code) ||
	((new_vnd != RMNETCTL_NEW_VND) && (new_vnd != RMNETCTL_FREE_VND))) {
		return_code = RMNETCTL_INVALID_ARG;
		break;
	}
	if (new_vnd ==  RMNETCTL_NEW_VND)
		request.message_type = RMNET_NETLINK_NEW_VND;
	else
		request.message_type = RMNET_NETLINK_FREE_VND;

	request.arg_length = sizeof(uint32_t);
	request.vnd.id = id;

	if ((*error_code = rmnetctl_transact(hndl, &request, &response))
		!= RMNETCTL_SUCCESS)
		break;
	if (_rmnetctl_check_code(response.crd, error_code) != RMNETCTL_SUCCESS)
		break;

	return_code = _rmnetctl_set_codes(response.return_code, error_code);
	} while(0);
	return return_code;
}