/*
 * Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The OpenAirInterface Software Alliance licenses this file to You under
 * the OAI Public License, Version 1.1  (the "License"); you may not use this file
 * except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.openairinterface.org/?page_id=698
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *-------------------------------------------------------------------------------
 * For more information about the OpenAirInterface (OAI) Software Alliance:
 *      contact@openairinterface.org
 */

#ifndef NAS_MESSAGE_H_
#define NAS_MESSAGE_H_

#include "mm_msg.h"
#include "sm_msg.h"
#include "common_types.h"

/***********************************/
/********test mac and encrypt/decrypt********/
/***********************************/
#define DIRECTION__ 1//SECU_DIRECTION_DOWNLINK
#define TEST_MAC_ENCRYPT_DECRYPT__	0

#define NAS_MESSAGE_SECURITY_HEADER_SIZE  7

/*********************************************************/
/************************* 9.1 24501**********************/

/* Structure of security protected header */
typedef struct nas_message_security_header_s {
#ifdef __LITTLE_ENDIAN_BITFIELD
  extended_protocol_discriminator_t extended_protocol_discriminator;  //3gpp_24.501.h
  uint8_t security_header_type :4;
  uint8_t spare_half_octet :4;
#endif
#ifdef __BIG_ENDIAN_BITFIELD
  uint8_t spare_half_octet:4;
  uint8_t security_header_type:4;
#endif
  uint32_t message_authentication_code;
  uint8_t sequence_number;
} __attribute__((__packed__)) nas_message_security_header_t;

/* Structure of plain NAS message */
typedef union {
  MM_msg mm; /* NAS MM */
  SM_msg sm; /* NAS SM  */
} nas_message_plain_t;

/* Structure of security protected NAS message */
typedef struct nas_message_security_protected_s {
  nas_message_security_header_t header;
  nas_message_plain_t plain;
} nas_message_security_protected_t;

/*
 * Structure of a layer 3 NAS message
 */
typedef struct {
  nas_message_security_header_t header;
  nas_message_security_protected_t security_protected;
  nas_message_plain_t plain;
} nas_message_t;

typedef struct nas_message_decode_status_s {
  uint8_t integrity_protected_message :1;
  uint8_t ciphered_message :1;
  uint8_t mac_matched :1;
  uint8_t security_context_available :1;
  int fivegmm_cause;
} nas_message_decode_status_t;

int nas_message_encode(unsigned char *buffer, const nas_message_t *const msg,
                       size_t length, void *security);

int nas_message_decode(const unsigned char *const buffer, nas_message_t *msg,
                       size_t length, void *security,
                       nas_message_decode_status_t *status);

#endif
