rrc_eNB_S1AP.c

/*
 * 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
 */

/*! \file rrc_eNB_S1AP.c
 * \brief rrc S1AP procedures for eNB
 * \author Navid Nikaein, Laurent Winckel, Sebastien ROUX, and Lionel GAUTHIER
 * \date 2013-2016
 * \version 1.0
 * \company Eurecom
 * \email: navid.nikaein@eurecom.fr
 */
#if defined(ENABLE_USE_MME)
# include "rrc_defs.h"
# include "rrc_extern.h"
# include "RRC/L2_INTERFACE/openair_rrc_L2_interface.h"
# include "RRC/LTE/MESSAGES/asn1_msg.h"
# include "rrc_eNB_UE_context.h"
# include "rrc_eNB_S1AP.h"
# include "enb_config.h"
# include "common/ran_context.h"
/****************************************/
# include "s1ap_eNB_defs.h"
# include "s1ap_eNB_management_procedures.h"
# include "s1ap_eNB_ue_context.h"
/****************************************/

# if defined(ENABLE_ITTI)
#   include "asn1_conversions.h"
#   include "intertask_interface.h"
#   include "pdcp.h"
#   include "pdcp_primitives.h"
#   include "s1ap_eNB.h"
# else
#   include "../../S1AP/s1ap_eNB.h"
# endif

#if defined(ENABLE_SECURITY)
#   include "UTIL/OSA/osa_defs.h"
#endif
#include "msc.h"

#include "UERadioAccessCapabilityInformation.h"

#include "gtpv1u_eNB_task.h"
#include "RRC/LTE/rrc_eNB_GTPV1U.h"

#include "TLVDecoder.h"
#include "S1AP_NAS-PDU.h"
#include "flexran_agent_common_internal.h"

extern RAN_CONTEXT_t RC;

/* Value to indicate an invalid UE initial id */
static const uint16_t UE_INITIAL_ID_INVALID = 0;

/* Masks for S1AP Encryption algorithms, EEA0 is always supported (not coded) */
static const uint16_t S1AP_ENCRYPTION_EEA1_MASK = 0x8000;
static const uint16_t S1AP_ENCRYPTION_EEA2_MASK = 0x4000;

/* Masks for S1AP Integrity algorithms, EIA0 is always supported (not coded) */
static const uint16_t S1AP_INTEGRITY_EIA1_MASK = 0x8000;
static const uint16_t S1AP_INTEGRITY_EIA2_MASK = 0x4000;

#if (RRC_VERSION >= MAKE_VERSION(9, 2, 0))
# define INTEGRITY_ALGORITHM_NONE SecurityAlgorithmConfig__integrityProtAlgorithm_eia0_v920
#else
#ifdef EXMIMO_IOT
# define INTEGRITY_ALGORITHM_NONE SecurityAlgorithmConfig__integrityProtAlgorithm_eia2
#else
# define INTEGRITY_ALGORITHM_NONE SecurityAlgorithmConfig__integrityProtAlgorithm_reserved
#endif
#endif

void extract_imsi(uint8_t *pdu_buf, uint32_t pdu_len, rrc_eNB_ue_context_t *ue_context_pP)
{
  /* Process NAS message locally to get the IMSI */
  nas_message_t nas_msg;
  memset(&nas_msg, 0, sizeof(nas_message_t));

  int size = 0;

  nas_message_security_header_t *header = &nas_msg.header;
  /* Decode the first octet of the header (security header type or EPS
  * bearer identity, and protocol discriminator) */
  DECODE_U8((char *) pdu_buf, *(uint8_t*) (header), size);

  /* Decode NAS message only if decodable*/
  if (!(header->security_header_type <= SECURITY_HEADER_TYPE_INTEGRITY_PROTECTED
      && header->protocol_discriminator == EPS_MOBILITY_MANAGEMENT_MESSAGE
      && pdu_len > NAS_MESSAGE_SECURITY_HEADER_SIZE))
    return;

  if (header->security_header_type != SECURITY_HEADER_TYPE_NOT_PROTECTED) {
    /* Decode the message authentication code */
    DECODE_U32((char *) pdu_buf+size, header->message_authentication_code, size);
    /* Decode the sequence number */
    DECODE_U8((char *) pdu_buf+size, header->sequence_number, size);
  }

  /* Note: the value of the pointer (i.e. the address) is given by value, so we
   * can modify it as we want. The callee retains the original address! */
  pdu_buf += size;
  pdu_len -= size;

  /* Decode plain NAS message */
  EMM_msg *e_msg = &nas_msg.plain.emm;
  emm_msg_header_t *emm_header = &e_msg->header;

  /* First decode the EMM message header */
  int e_head_size = 0;

  /* Check that buffer contains more than only the header */
  if (pdu_len <= sizeof(emm_msg_header_t))
    return;

  /* Decode the security header type and the protocol discriminator */
  DECODE_U8(pdu_buf + e_head_size, *(uint8_t *)(emm_header), e_head_size);
  /* Decode the message type */
  DECODE_U8(pdu_buf + e_head_size, emm_header->message_type, e_head_size);

  /* Check that this is the right message */
  if (emm_header->protocol_discriminator != EPS_MOBILITY_MANAGEMENT_MESSAGE)
    return;

  pdu_buf += e_head_size;
  pdu_len -= e_head_size;

  if (emm_header->message_type == IDENTITY_RESPONSE) {
    decode_identity_response(&e_msg->identity_response, pdu_buf, pdu_len);

    if (e_msg->identity_response.mobileidentity.imsi.typeofidentity == MOBILE_IDENTITY_IMSI) {
      memcpy(&ue_context_pP->ue_context.imsi,
             &e_msg->identity_response.mobileidentity.imsi,
             sizeof(ImsiMobileIdentity_t));
    }
  } else if (emm_header->message_type == ATTACH_REQUEST) {
    decode_attach_request(&e_msg->attach_request, pdu_buf, pdu_len);

    if (e_msg->attach_request.oldgutiorimsi.imsi.typeofidentity == MOBILE_IDENTITY_IMSI) {
      /* the following is very dirty, we cast (implicitly) from
       * ImsiEpsMobileIdentity_t to ImsiMobileIdentity_t*/
      memcpy(&ue_context_pP->ue_context.imsi,
             &e_msg->attach_request.oldgutiorimsi.imsi,
             sizeof(ImsiMobileIdentity_t));
    }
  }
}

# if defined(ENABLE_ITTI)
//------------------------------------------------------------------------------
/*
* Get the UE S1 struct containing hashtables S1_id/UE_id.
* Is also used to set the S1_id of the UE, depending on inputs.
*/
struct rrc_ue_s1ap_ids_s*
rrc_eNB_S1AP_get_ue_ids(
  eNB_RRC_INST* const rrc_instance_pP,
  const uint16_t ue_initial_id,
  const uint32_t eNB_ue_s1ap_id
)
//------------------------------------------------------------------------------
{
  rrc_ue_s1ap_ids_t *result = NULL;
  rrc_ue_s1ap_ids_t *result2 = NULL;
  /*****************************/
  instance_t instance = 0;
  s1ap_eNB_instance_t *s1ap_eNB_instance_p = NULL;
  s1ap_eNB_ue_context_t *ue_desc_p = NULL;
  rrc_eNB_ue_context_t *ue_context_p = NULL;
  /*****************************/
  hashtable_rc_t     h_rc;

  if (ue_initial_id != UE_INITIAL_ID_INVALID) {
    h_rc = hashtable_get(rrc_instance_pP->initial_id2_s1ap_ids, (hash_key_t)ue_initial_id, (void**)&result);

    if (h_rc == HASH_TABLE_OK) {
      
      if (eNB_ue_s1ap_id > 0) {
        h_rc = hashtable_get(rrc_instance_pP->s1ap_id2_s1ap_ids, (hash_key_t)eNB_ue_s1ap_id, (void**)&result2);
        
        if (h_rc != HASH_TABLE_OK) { // this case is equivalent to associate eNB_ue_s1ap_id and ue_initial_id
          result2 = malloc(sizeof(*result2));
          
          if (NULL != result2) {
            *result2 = *result;
            
            result2->eNB_ue_s1ap_id = eNB_ue_s1ap_id;
            result->eNB_ue_s1ap_id  = eNB_ue_s1ap_id;
            
            h_rc = hashtable_insert(rrc_instance_pP->s1ap_id2_s1ap_ids, (hash_key_t)eNB_ue_s1ap_id, result2);

            if (h_rc != HASH_TABLE_OK) {
              LOG_E(S1AP, "[eNB %ld] Error while hashtable_insert in s1ap_id2_s1ap_ids eNB_ue_s1ap_id %"PRIu32"\n", 
                rrc_instance_pP - RC.rrc[0], 
                eNB_ue_s1ap_id);
            }
          }

        } else { // here we should check that the association was done correctly
          
          if ((result->ue_initial_id != result2->ue_initial_id) || (result->eNB_ue_s1ap_id != result2->eNB_ue_s1ap_id)) {
            
            LOG_E(S1AP, "[eNB %ld] Error while hashtable_get, two rrc_ue_s1ap_ids_t that should be equal, are not:\n \
              ue_initial_id 1 = %"PRIu16",\n \
              ue_initial_id 2 = %"PRIu16",\n \
              eNB_ue_s1ap_id 1 = %"PRIu32",\n \
              eNB_ue_s1ap_id 2 = %"PRIu32"\n",
                rrc_instance_pP - RC.rrc[0],
                result->ue_initial_id,
                result2->ue_initial_id,
                result->eNB_ue_s1ap_id,
                result2->eNB_ue_s1ap_id);

          }

        }
      } // end if if (eNB_ue_s1ap_id > 0)

    } else { // end if (h_rc == HASH_TABLE_OK)

      LOG_E(S1AP, "[eNB %ld] In hashtable_get, couldn't find in initial_id2_s1ap_ids ue_initial_id %"PRIu16"\n", 
        rrc_instance_pP - RC.rrc[0], 
        ue_initial_id);
      /*
      * At the moment this is written, this case shouldn't (cannot) happen and is equivalent to an error.
      * One could try to find the struct instance based on s1ap_id2_s1ap_ids and eNB_ue_s1ap_id (if > 0),
      * but this behavior is not expected at the moment.
      */

    } // end else (h_rc != HASH_TABLE_OK)

  } else { // end if (ue_initial_id != UE_INITIAL_ID_INVALID)

    if (eNB_ue_s1ap_id > 0) {
	    h_rc = hashtable_get(rrc_instance_pP->s1ap_id2_s1ap_ids, (hash_key_t)eNB_ue_s1ap_id, (void**)&result);

      if (h_rc != HASH_TABLE_OK) {
        /*
        * This case is uncommon, but can happen when:
        * -> if the first NAS message was a Detach Request (non exhaustiv), the UE RRC context exist 
        * but is not associated with eNB_ue_s1ap_id
        * -> ... (?)
        */
        LOG_E(S1AP, "[eNB %ld] In hashtable_get, couldn't find in s1ap_id2_s1ap_ids eNB_ue_s1ap_id %"PRIu32", trying to find it through S1AP context\n", 
          rrc_instance_pP - RC.rrc[0], 
          eNB_ue_s1ap_id);

        instance = ENB_MODULE_ID_TO_INSTANCE(rrc_instance_pP - RC.rrc[0]); // get eNB instance

        s1ap_eNB_instance_p = s1ap_eNB_get_instance(instance); // get s1ap_eNB_instance

        ue_desc_p = s1ap_eNB_get_ue_context(s1ap_eNB_instance_p, eNB_ue_s1ap_id); // get s1ap_eNB_ue_context

        if (ue_desc_p != NULL) {

          result = rrc_eNB_S1AP_get_ue_ids(rrc_instance_pP, ue_desc_p->ue_initial_id, eNB_ue_s1ap_id);

          ue_context_p = rrc_eNB_get_ue_context(RC.rrc[ENB_INSTANCE_TO_MODULE_ID(instance)], result->ue_rnti);

          if ((ue_context_p != NULL) && (ue_context_p->ue_context.eNB_ue_s1ap_id == 0)) {

            ue_context_p->ue_context.eNB_ue_s1ap_id = eNB_ue_s1ap_id;
          
          } else {

            LOG_E(RRC, "[eNB %ld] Incoherence between RRC context and S1AP context (%d != %d) for UE RNTI %d or UE RRC context doesn't exist\n",
              rrc_instance_pP - RC.rrc[0],
              ue_context_p->ue_context.eNB_ue_s1ap_id,
              eNB_ue_s1ap_id,
              result->ue_rnti);

          }

        } else {

          LOG_E(S1AP, "[eNB %ld] In hashtable_get, couldn't find in s1ap_id2_s1ap_ids eNB_ue_s1ap_id %"PRIu32", even when looking at S1AP context\n", 
          rrc_instance_pP - RC.rrc[0], 
          eNB_ue_s1ap_id);
          
        }

      } // end if (h_rc != HASH_TABLE_OK)
    } // end if (eNB_ue_s1ap_id > 0)
  } // end else (ue_initial_id == UE_INITIAL_ID_INVALID)

  return result;
}

//------------------------------------------------------------------------------
/*
* Remove UE ids (ue_initial_id and S1_id) from hashtables.
*/
void
rrc_eNB_S1AP_remove_ue_ids(
  eNB_RRC_INST *const rrc_instance_pP,
  struct rrc_ue_s1ap_ids_s *const ue_ids_pP
)
//------------------------------------------------------------------------------
{
  const uint16_t ue_initial_id  = ue_ids_pP->ue_initial_id;
  const uint32_t eNB_ue_s1ap_id = ue_ids_pP->eNB_ue_s1ap_id;

  hashtable_rc_t h_rc;

  if (rrc_instance_pP == NULL) {
    LOG_E(RRC, "Bad RRC instance\n");
    return;
  }

  if (ue_ids_pP == NULL) {
    LOG_E(RRC, "Trying to free a NULL S1AP UE IDs\n");
    return;
  }

  if (eNB_ue_s1ap_id > 0) {
	  h_rc = hashtable_remove(rrc_instance_pP->s1ap_id2_s1ap_ids, (hash_key_t)eNB_ue_s1ap_id);
	
    if (h_rc != HASH_TABLE_OK) {
	    LOG_W(RRC, "S1AP Did not find entry in hashtable s1ap_id2_s1ap_ids for eNB_ue_s1ap_id %u\n", eNB_ue_s1ap_id);
	  } else {
	    LOG_W(RRC, "S1AP removed entry in hashtable s1ap_id2_s1ap_ids for eNB_ue_s1ap_id %u\n", eNB_ue_s1ap_id);
	  }
  }

  if (ue_initial_id != UE_INITIAL_ID_INVALID) {
    h_rc = hashtable_remove(rrc_instance_pP->initial_id2_s1ap_ids, (hash_key_t)ue_initial_id);
 
    if (h_rc != HASH_TABLE_OK) {
      LOG_W(RRC, "S1AP Did not find entry in hashtable initial_id2_s1ap_ids for ue_initial_id %u\n", ue_initial_id);
    } else {
      LOG_W(RRC, "S1AP removed entry in hashtable initial_id2_s1ap_ids for ue_initial_id %u\n", ue_initial_id);
    }
  }
}

/*! \fn uint16_t get_next_ue_initial_id(uint8_t mod_id)
 *\brief provide an UE initial ID for S1AP initial communication.
 *\param mod_id Instance ID of eNB.
 *\return the UE initial ID.
 */
//------------------------------------------------------------------------------
static uint16_t
get_next_ue_initial_id(
  const module_id_t mod_id
)
//------------------------------------------------------------------------------
{
  static uint16_t ue_initial_id[NUMBER_OF_eNB_MAX];
  ue_initial_id[mod_id]++;

  /* Never use UE_INITIAL_ID_INVALID this is the invalid id! */
  if (ue_initial_id[mod_id] == UE_INITIAL_ID_INVALID) {
    ue_initial_id[mod_id]++;
  }

  return ue_initial_id[mod_id];
}




/*! \fn uint8_t get_UE_index_from_s1ap_ids(uint8_t mod_id, uint16_t ue_initial_id, uint32_t eNB_ue_s1ap_id)
 *\brief retrieve UE index in the eNB from the UE initial ID if not equal to UE_INDEX_INVALID or
 *\brief from the eNB_ue_s1ap_id previously transmitted by S1AP.
 *\param mod_id Instance ID of eNB.
 *\param ue_initial_id The UE initial ID sent to S1AP.
 *\param eNB_ue_s1ap_id The value sent by S1AP.
 *\return the UE index or UE_INDEX_INVALID if not found.
 */
static struct rrc_eNB_ue_context_s*
rrc_eNB_get_ue_context_from_s1ap_ids(
  const instance_t  instanceP,
  const uint16_t    ue_initial_idP,
  const uint32_t    eNB_ue_s1ap_idP
)
{
  rrc_ue_s1ap_ids_t* temp = NULL;

  temp = rrc_eNB_S1AP_get_ue_ids(RC.rrc[ENB_INSTANCE_TO_MODULE_ID(instanceP)], ue_initial_idP, eNB_ue_s1ap_idP);

  if (temp != NULL) {
    return rrc_eNB_get_ue_context(RC.rrc[ENB_INSTANCE_TO_MODULE_ID(instanceP)], temp->ue_rnti);
  }

  return NULL;
}

/*! \fn e_SecurityAlgorithmConfig__cipheringAlgorithm rrc_eNB_select_ciphering(uint16_t algorithms)
 *\brief analyze available encryption algorithms bit mask and return the relevant one.
 *\param algorithms The bit mask of available algorithms received from S1AP.
 *\return the selected algorithm.
 */
static CipheringAlgorithm_r12_t rrc_eNB_select_ciphering(uint16_t algorithms)
{

//#warning "Forced   return SecurityAlgorithmConfig__cipheringAlgorithm_eea0, to be deleted in future"
  return CipheringAlgorithm_r12_eea0;

  if (algorithms & S1AP_ENCRYPTION_EEA2_MASK) {
    return CipheringAlgorithm_r12_eea2;
  }

  if (algorithms & S1AP_ENCRYPTION_EEA1_MASK) {
    return CipheringAlgorithm_r12_eea1;
  }

  return CipheringAlgorithm_r12_eea0;
}

/*! \fn e_SecurityAlgorithmConfig__integrityProtAlgorithm rrc_eNB_select_integrity(uint16_t algorithms)
 *\brief analyze available integrity algorithms bit mask and return the relevant one.
 *\param algorithms The bit mask of available algorithms received from S1AP.
 *\return the selected algorithm.
 */
static e_SecurityAlgorithmConfig__integrityProtAlgorithm rrc_eNB_select_integrity(uint16_t algorithms)
{

  if (algorithms & S1AP_INTEGRITY_EIA2_MASK) {
    return SecurityAlgorithmConfig__integrityProtAlgorithm_eia2;
  }

  if (algorithms & S1AP_INTEGRITY_EIA1_MASK) {
    return SecurityAlgorithmConfig__integrityProtAlgorithm_eia1;
  }

  return INTEGRITY_ALGORITHM_NONE;
}

/*! \fn int rrc_eNB_process_security (uint8_t mod_id, uint8_t ue_index, security_capabilities_t *security_capabilities)
 *\brief save and analyze available security algorithms bit mask and select relevant ones.
 *\param mod_id Instance ID of eNB.
 *\param ue_index Instance ID of UE in the eNB.
 *\param security_capabilities The security capabilities received from S1AP.
 *\return TRUE if at least one algorithm has been changed else FALSE.
 */
static int
rrc_eNB_process_security(
  const protocol_ctxt_t* const ctxt_pP,
  rrc_eNB_ue_context_t*          const ue_context_pP,
  security_capabilities_t* security_capabilities_pP
)
{
  boolean_t                                         changed = FALSE;
  CipheringAlgorithm_r12_t                          cipheringAlgorithm;
  e_SecurityAlgorithmConfig__integrityProtAlgorithm integrityProtAlgorithm;

  /* Save security parameters */
  ue_context_pP->ue_context.security_capabilities = *security_capabilities_pP;

  // translation
  LOG_D(RRC,
        "[eNB %d] NAS security_capabilities.encryption_algorithms %u AS ciphering_algorithm %lu NAS security_capabilities.integrity_algorithms %u AS integrity_algorithm %u\n",
        ctxt_pP->module_id,
        ue_context_pP->ue_context.security_capabilities.encryption_algorithms,
        (unsigned long)ue_context_pP->ue_context.ciphering_algorithm,
        ue_context_pP->ue_context.security_capabilities.integrity_algorithms,
        ue_context_pP->ue_context.integrity_algorithm);
  /* Select relevant algorithms */
  cipheringAlgorithm = rrc_eNB_select_ciphering (ue_context_pP->ue_context.security_capabilities.encryption_algorithms);

  if (ue_context_pP->ue_context.ciphering_algorithm != cipheringAlgorithm) {
    ue_context_pP->ue_context.ciphering_algorithm = cipheringAlgorithm;
    changed = TRUE;
  }

  integrityProtAlgorithm = rrc_eNB_select_integrity (ue_context_pP->ue_context.security_capabilities.integrity_algorithms);

  if (ue_context_pP->ue_context.integrity_algorithm != integrityProtAlgorithm) {
    ue_context_pP->ue_context.integrity_algorithm = integrityProtAlgorithm;
    changed = TRUE;
  }

  LOG_I (RRC, "[eNB %d][UE %x] Selected security algorithms (%p): %lx, %x, %s\n",
         ctxt_pP->module_id,
         ue_context_pP->ue_context.rnti,
         security_capabilities_pP,
         (unsigned long)cipheringAlgorithm,
         integrityProtAlgorithm,
         changed ? "changed" : "same");

  return changed;
}

/*! \fn void process_eNB_security_key (const protocol_ctxt_t* const ctxt_pP, eNB_RRC_UE_t * const ue_context_pP, uint8_t *security_key)
 *\brief save security key.
 *\param ctxt_pP         Running context.
 *\param ue_context_pP   UE context.
 *\param security_key_pP The security key received from S1AP.
 */
//------------------------------------------------------------------------------
static void process_eNB_security_key (
  const protocol_ctxt_t* const ctxt_pP,
  rrc_eNB_ue_context_t*          const ue_context_pP,
  uint8_t*               security_key_pP
)
//------------------------------------------------------------------------------
{
#if defined(ENABLE_SECURITY)
  char ascii_buffer[65];
  uint8_t i;

  /* Saves the security key */
  memcpy (ue_context_pP->ue_context.kenb, security_key_pP, SECURITY_KEY_LENGTH);
  memset (ue_context_pP->ue_context.nh, 0, SECURITY_KEY_LENGTH);
  ue_context_pP->ue_context.nh_ncc = -1;

  for (i = 0; i < 32; i++) {
    sprintf(&ascii_buffer[2 * i], "%02X", ue_context_pP->ue_context.kenb[i]);
  }

  ascii_buffer[2 * i] = '\0';

  LOG_I (RRC, "[eNB %d][UE %x] Saved security key %s\n", ctxt_pP->module_id, ue_context_pP->ue_context.rnti, ascii_buffer);
#endif
}


//------------------------------------------------------------------------------
void
rrc_pdcp_config_security(
  const protocol_ctxt_t* const ctxt_pP,
  rrc_eNB_ue_context_t*          const ue_context_pP,
  const uint8_t send_security_mode_command
)
//------------------------------------------------------------------------------
{

#if defined(ENABLE_SECURITY)


  SRB_ToAddModList_t*                 SRB_configList = ue_context_pP->ue_context.SRB_configList;
  uint8_t                            *kRRCenc = NULL;
  uint8_t                            *kRRCint = NULL;
  uint8_t                            *kUPenc = NULL;
  pdcp_t                             *pdcp_p   = NULL;
  static int                          print_keys= 1;
  hashtable_rc_t                      h_rc;
  hash_key_t                          key;

  /* Derive the keys from kenb */
  if (SRB_configList != NULL) {
    derive_key_up_enc(ue_context_pP->ue_context.ciphering_algorithm,
                      ue_context_pP->ue_context.kenb,
                      &kUPenc);
  }

  derive_key_rrc_enc(ue_context_pP->ue_context.ciphering_algorithm,
                     ue_context_pP->ue_context.kenb,
                     &kRRCenc);
  derive_key_rrc_int(ue_context_pP->ue_context.integrity_algorithm,
                     ue_context_pP->ue_context.kenb,
                     &kRRCint);

#if !defined(USRP_REC_PLAY)
  SET_LOG_DUMP(DEBUG_SECURITY) ;
#endif
  

  if ( LOG_DUMPFLAG( DEBUG_SECURITY ) ) {
    if (print_keys ==1 ) {
      print_keys =0;

      LOG_DUMPMSG(RRC, DEBUG_SECURITY, ue_context_pP->ue_context.kenb, 32,"\nKeNB:" );
      LOG_DUMPMSG(RRC, DEBUG_SECURITY, kRRCenc, 32,"\nKRRCenc:" );
      LOG_DUMPMSG(RRC, DEBUG_SECURITY, kRRCint, 32,"\nKRRCint:" );
    }
  }

  key = PDCP_COLL_KEY_VALUE(ctxt_pP->module_id, ctxt_pP->rnti, ctxt_pP->enb_flag, DCCH, SRB_FLAG_YES);
  h_rc = hashtable_get(pdcp_coll_p, key, (void**)&pdcp_p);


  if (h_rc == HASH_TABLE_OK) {
    pdcp_config_set_security(
      ctxt_pP,
      pdcp_p,
      DCCH,
      DCCH+2,
      (send_security_mode_command == TRUE)  ?
      0 | (ue_context_pP->ue_context.integrity_algorithm << 4) :
      (ue_context_pP->ue_context.ciphering_algorithm )         |
      (ue_context_pP->ue_context.integrity_algorithm << 4),
      kRRCenc,
      kRRCint,
      kUPenc);
  } else {
    LOG_E(RRC,
          PROTOCOL_RRC_CTXT_UE_FMT"Could not get PDCP instance for SRB DCCH %u\n",
          PROTOCOL_RRC_CTXT_UE_ARGS(ctxt_pP),
          DCCH);
  }

#endif
}

//------------------------------------------------------------------------------
void
rrc_eNB_send_S1AP_INITIAL_CONTEXT_SETUP_RESP(
  const protocol_ctxt_t* const ctxt_pP,
  rrc_eNB_ue_context_t*          const ue_context_pP
)
//------------------------------------------------------------------------------
{
  MessageDef      *msg_p         = NULL;
  int e_rab;
  int e_rabs_done = 0;
  int e_rabs_failed = 0;

  msg_p = itti_alloc_new_message (TASK_RRC_ENB, S1AP_INITIAL_CONTEXT_SETUP_RESP);
  S1AP_INITIAL_CONTEXT_SETUP_RESP (msg_p).eNB_ue_s1ap_id = ue_context_pP->ue_context.eNB_ue_s1ap_id;

  for (e_rab = 0; e_rab < ue_context_pP->ue_context.nb_of_e_rabs; e_rab++) {
    if (ue_context_pP->ue_context.e_rab[e_rab].status == E_RAB_STATUS_DONE) {
      e_rabs_done++;
      S1AP_INITIAL_CONTEXT_SETUP_RESP (msg_p).e_rabs[e_rab].e_rab_id = ue_context_pP->ue_context.e_rab[e_rab].param.e_rab_id;
      // TODO add other information from S1-U when it will be integrated
      S1AP_INITIAL_CONTEXT_SETUP_RESP (msg_p).e_rabs[e_rab].gtp_teid = ue_context_pP->ue_context.enb_gtp_teid[e_rab];
      S1AP_INITIAL_CONTEXT_SETUP_RESP (msg_p).e_rabs[e_rab].eNB_addr = ue_context_pP->ue_context.enb_gtp_addrs[e_rab];
      S1AP_INITIAL_CONTEXT_SETUP_RESP (msg_p).e_rabs[e_rab].eNB_addr.length = 4;
      ue_context_pP->ue_context.e_rab[e_rab].status = E_RAB_STATUS_ESTABLISHED;
    } else {
      e_rabs_failed++;
      ue_context_pP->ue_context.e_rab[e_rab].status = E_RAB_STATUS_FAILED;
      S1AP_INITIAL_CONTEXT_SETUP_RESP (msg_p).e_rabs_failed[e_rab].e_rab_id = ue_context_pP->ue_context.e_rab[e_rab].param.e_rab_id;
      // TODO add cause when it will be integrated
    }
  }

  MSC_LOG_TX_MESSAGE(
    MSC_RRC_ENB,
    MSC_S1AP_ENB,
    (const char *)&S1AP_INITIAL_CONTEXT_SETUP_RESP (msg_p),
    sizeof(s1ap_initial_context_setup_resp_t),
    MSC_AS_TIME_FMT" INITIAL_CONTEXT_SETUP_RESP UE %X eNB_ue_s1ap_id %u e_rabs:%u succ %u fail",
    MSC_AS_TIME_ARGS(ctxt_pP),
    ue_context_pP->ue_id_rnti,
    S1AP_INITIAL_CONTEXT_SETUP_RESP (msg_p).eNB_ue_s1ap_id,
    e_rabs_done, e_rabs_failed);


  S1AP_INITIAL_CONTEXT_SETUP_RESP (msg_p).nb_of_e_rabs = e_rabs_done;
  S1AP_INITIAL_CONTEXT_SETUP_RESP (msg_p).nb_of_e_rabs_failed = e_rabs_failed;

  itti_send_msg_to_task (TASK_S1AP, ctxt_pP->instance, msg_p);
}
# endif

//------------------------------------------------------------------------------
void
rrc_eNB_send_S1AP_UPLINK_NAS(
  const protocol_ctxt_t*    const ctxt_pP,
  rrc_eNB_ue_context_t*             const ue_context_pP,
  UL_DCCH_Message_t*        const ul_dcch_msg
)
//------------------------------------------------------------------------------
{
#if defined(ENABLE_ITTI)
  {
    ULInformationTransfer_t *ulInformationTransfer = &ul_dcch_msg->message.choice.c1.choice.ulInformationTransfer;

    if ((ulInformationTransfer->criticalExtensions.present == ULInformationTransfer__criticalExtensions_PR_c1)
    && (ulInformationTransfer->criticalExtensions.choice.c1.present
    == ULInformationTransfer__criticalExtensions__c1_PR_ulInformationTransfer_r8)
    && (ulInformationTransfer->criticalExtensions.choice.c1.choice.ulInformationTransfer_r8.dedicatedInfoType.present
    == ULInformationTransfer_r8_IEs__dedicatedInfoType_PR_dedicatedInfoNAS)) {
      /* This message hold a dedicated info NAS payload, forward it to NAS */
      struct ULInformationTransfer_r8_IEs__dedicatedInfoType *dedicatedInfoType =
          &ulInformationTransfer->criticalExtensions.choice.c1.choice.ulInformationTransfer_r8.dedicatedInfoType;
      uint32_t pdu_length;
      uint8_t *pdu_buffer;
      MessageDef *msg_p;

      pdu_length = dedicatedInfoType->choice.dedicatedInfoNAS.size;
      pdu_buffer = dedicatedInfoType->choice.dedicatedInfoNAS.buf;

      msg_p = itti_alloc_new_message (TASK_RRC_ENB, S1AP_UPLINK_NAS);
      S1AP_UPLINK_NAS (msg_p).eNB_ue_s1ap_id = ue_context_pP->ue_context.eNB_ue_s1ap_id;
      S1AP_UPLINK_NAS (msg_p).nas_pdu.length = pdu_length;
      S1AP_UPLINK_NAS (msg_p).nas_pdu.buffer = pdu_buffer;

      extract_imsi(S1AP_UPLINK_NAS (msg_p).nas_pdu.buffer,
                   S1AP_UPLINK_NAS (msg_p).nas_pdu.length,
                   ue_context_pP);

      itti_send_msg_to_task (TASK_S1AP, ctxt_pP->instance, msg_p);
    }
  }
#else
  {
    ULInformationTransfer_t *ulInformationTransfer;
    ulInformationTransfer =
    &ul_dcch_msg->message.choice.c1.choice.
    ulInformationTransfer;

    if (ulInformationTransfer->criticalExtensions.present ==
    ULInformationTransfer__criticalExtensions_PR_c1) {
      if (ulInformationTransfer->criticalExtensions.choice.c1.present ==
      ULInformationTransfer__criticalExtensions__c1_PR_ulInformationTransfer_r8) {

        ULInformationTransfer_r8_IEs_t
        *ulInformationTransferR8;
        ulInformationTransferR8 =
        &ulInformationTransfer->criticalExtensions.choice.
        c1.choice.ulInformationTransfer_r8;

        if (ulInformationTransferR8->dedicatedInfoType.present ==
            ULInformationTransfer_r8_IEs__dedicatedInfoType_PR_dedicatedInfoNAS) {

          extract_imsi(ulInformationTransferR8->dedicatedInfoType.choice.dedicatedInfoNAS.buf,
                       ulInformationTransferR8->dedicatedInfoType.choice.dedicatedInfoNAS.size,
                       ue_context_pP);

          s1ap_eNB_new_data_request (mod_id, ue_index,
              ulInformationTransferR8->dedicatedInfoType.choice.dedicatedInfoNAS.buf,
              ulInformationTransferR8->dedicatedInfoType.choice.dedicatedInfoNAS.size);
        }
      }
    }
  }
#endif
}

//------------------------------------------------------------------------------
void rrc_eNB_send_S1AP_UE_CAPABILITIES_IND(
  const protocol_ctxt_t* const ctxt_pP,
  rrc_eNB_ue_context_t*          const ue_context_pP,
  UL_DCCH_Message_t* ul_dcch_msg
)
//------------------------------------------------------------------------------
{
  UECapabilityInformation_t *ueCapabilityInformation = &ul_dcch_msg->message.choice.c1.choice.ueCapabilityInformation;
  /* 4096 is arbitrary, should be big enough */
  unsigned char buf[4096];
  unsigned char *buf2;
  UERadioAccessCapabilityInformation_t rac;

  if (ueCapabilityInformation->criticalExtensions.present != UECapabilityInformation__criticalExtensions_PR_c1
      || ueCapabilityInformation->criticalExtensions.choice.c1.present != UECapabilityInformation__criticalExtensions__c1_PR_ueCapabilityInformation_r8) {
    LOG_E(RRC, "[eNB %d][UE %x] bad UE capabilities\n", ctxt_pP->module_id, ue_context_pP->ue_context.rnti);
    return;
  }

  asn_enc_rval_t ret = uper_encode_to_buffer(&asn_DEF_UECapabilityInformation, NULL, ueCapabilityInformation, buf, 4096);

  if (ret.encoded == -1) abort();

  memset(&rac, 0, sizeof(UERadioAccessCapabilityInformation_t));

  rac.criticalExtensions.present = UERadioAccessCapabilityInformation__criticalExtensions_PR_c1;
  rac.criticalExtensions.choice.c1.present = UERadioAccessCapabilityInformation__criticalExtensions__c1_PR_ueRadioAccessCapabilityInformation_r8;
  rac.criticalExtensions.choice.c1.choice.ueRadioAccessCapabilityInformation_r8.ue_RadioAccessCapabilityInfo.buf = buf;
  rac.criticalExtensions.choice.c1.choice.ueRadioAccessCapabilityInformation_r8.ue_RadioAccessCapabilityInfo.size = (ret.encoded+7)/8;
  rac.criticalExtensions.choice.c1.choice.ueRadioAccessCapabilityInformation_r8.nonCriticalExtension = NULL;

  /* 8192 is arbitrary, should be big enough */
  buf2 = malloc16(8192);
  if (buf2 == NULL) abort();

  ret = uper_encode_to_buffer(&asn_DEF_UERadioAccessCapabilityInformation, NULL, &rac, buf2, 8192);

  if (ret.encoded == -1) abort();

  MessageDef *msg_p;

  msg_p = itti_alloc_new_message (TASK_RRC_ENB, S1AP_UE_CAPABILITIES_IND);
  S1AP_UE_CAPABILITIES_IND (msg_p).eNB_ue_s1ap_id = ue_context_pP->ue_context.eNB_ue_s1ap_id;
  S1AP_UE_CAPABILITIES_IND (msg_p).ue_radio_cap.length = (ret.encoded+7)/8;
  S1AP_UE_CAPABILITIES_IND (msg_p).ue_radio_cap.buffer = buf2;

  itti_send_msg_to_task (TASK_S1AP, ctxt_pP->instance, msg_p);
}

//------------------------------------------------------------------------------
/*
* Initial UE NAS message on S1AP.
*/
void
rrc_eNB_send_S1AP_NAS_FIRST_REQ(
  const protocol_ctxt_t* const ctxt_pP,
  rrc_eNB_ue_context_t* const ue_context_pP,
  RRCConnectionSetupComplete_r8_IEs_t* rrcConnectionSetupComplete
)
//------------------------------------------------------------------------------
{
  eNB_RRC_INST *rrc = RC.rrc[ctxt_pP->module_id];

#if defined(ENABLE_ITTI)
  {
    MessageDef*         message_p         = NULL;
    rrc_ue_s1ap_ids_t*  rrc_ue_s1ap_ids_p = NULL;
    hashtable_rc_t      h_rc;

    message_p = itti_alloc_new_message(TASK_RRC_ENB, S1AP_NAS_FIRST_REQ);
    memset(&message_p->ittiMsg.s1ap_nas_first_req, 0, sizeof(s1ap_nas_first_req_t));

    ue_context_pP->ue_context.ue_initial_id = get_next_ue_initial_id(ctxt_pP->module_id);
    
    S1AP_NAS_FIRST_REQ(message_p).ue_initial_id = ue_context_pP->ue_context.ue_initial_id;

    rrc_ue_s1ap_ids_p = malloc(sizeof(*rrc_ue_s1ap_ids_p));
    rrc_ue_s1ap_ids_p->ue_initial_id  = ue_context_pP->ue_context.ue_initial_id;
    rrc_ue_s1ap_ids_p->eNB_ue_s1ap_id = UE_INITIAL_ID_INVALID;
    rrc_ue_s1ap_ids_p->ue_rnti        = ctxt_pP->rnti;

    h_rc = hashtable_insert(RC.rrc[ctxt_pP->module_id]->initial_id2_s1ap_ids,
    		                (hash_key_t)ue_context_pP->ue_context.ue_initial_id,
    		                rrc_ue_s1ap_ids_p);

    if (h_rc != HASH_TABLE_OK) {
      LOG_E(S1AP, "[eNB %d] Error while hashtable_insert in initial_id2_s1ap_ids ue_initial_id %u\n",
        ctxt_pP->module_id, 
        ue_context_pP->ue_context.ue_initial_id);
    }

    /* Assume that cause is coded in the same way in RRC and S1ap, just check that the value is in S1ap range */
    AssertFatal(ue_context_pP->ue_context.establishment_cause < RRC_CAUSE_LAST,
      "Establishment cause invalid (%jd/%d) for eNB %d!",
      ue_context_pP->ue_context.establishment_cause, 
      RRC_CAUSE_LAST, 
      ctxt_pP->module_id);

    S1AP_NAS_FIRST_REQ (message_p).establishment_cause = ue_context_pP->ue_context.establishment_cause;

    /* Forward NAS message */ 
    S1AP_NAS_FIRST_REQ (message_p).nas_pdu.buffer = rrcConnectionSetupComplete->dedicatedInfoNAS.buf;
    S1AP_NAS_FIRST_REQ (message_p).nas_pdu.length = rrcConnectionSetupComplete->dedicatedInfoNAS.size;

    extract_imsi(S1AP_NAS_FIRST_REQ (message_p).nas_pdu.buffer,
                 S1AP_NAS_FIRST_REQ (message_p).nas_pdu.length,
                 ue_context_pP);

    /* Fill UE identities with available information */
    {
      S1AP_NAS_FIRST_REQ (message_p).ue_identity.presenceMask = UE_IDENTITIES_NONE;

      if (ue_context_pP->ue_context.Initialue_identity_s_TMSI.presence) {
        /* Fill s-TMSI */
        UE_S_TMSI* s_TMSI = &ue_context_pP->ue_context.Initialue_identity_s_TMSI;

        S1AP_NAS_FIRST_REQ (message_p).ue_identity.presenceMask |= UE_IDENTITIES_s_tmsi;
        S1AP_NAS_FIRST_REQ (message_p).ue_identity.s_tmsi.mme_code = s_TMSI->mme_code;
        S1AP_NAS_FIRST_REQ (message_p).ue_identity.s_tmsi.m_tmsi = s_TMSI->m_tmsi;

        LOG_I(S1AP, "[eNB %d] Build S1AP_NAS_FIRST_REQ with s_TMSI: MME code %u M-TMSI %u ue %x\n",
            ctxt_pP->module_id,
            S1AP_NAS_FIRST_REQ (message_p).ue_identity.s_tmsi.mme_code,
            S1AP_NAS_FIRST_REQ (message_p).ue_identity.s_tmsi.m_tmsi,
            ue_context_pP->ue_context.rnti);
      } // end if S-TMSI presence

      /* selected_plmn_identity: IE is 1-based, convert to 0-based (C array) */
      int selected_plmn_identity = rrcConnectionSetupComplete->selectedPLMN_Identity - 1;
      S1AP_NAS_FIRST_REQ(message_p).selected_plmn_identity = selected_plmn_identity;

      if (rrcConnectionSetupComplete->registeredMME != NULL) {
        /* Fill GUMMEI */
        struct RegisteredMME *r_mme = rrcConnectionSetupComplete->registeredMME;

        S1AP_NAS_FIRST_REQ (message_p).ue_identity.presenceMask |= UE_IDENTITIES_gummei;

        if (r_mme->plmn_Identity != NULL) {
          if ((r_mme->plmn_Identity->mcc != NULL) && (r_mme->plmn_Identity->mcc->list.count > 0)) {
            /* Use first indicated PLMN MCC if it is defined */
            S1AP_NAS_FIRST_REQ (message_p).ue_identity.gummei.mcc = *r_mme->plmn_Identity->mcc->list.array[selected_plmn_identity];
            
            LOG_I(S1AP, "[eNB %d] Build S1AP_NAS_FIRST_REQ adding in s_TMSI: GUMMEI MCC %u ue %x\n",
              ctxt_pP->module_id,
              S1AP_NAS_FIRST_REQ (message_p).ue_identity.gummei.mcc,
              ue_context_pP->ue_context.rnti);
          }

          if (r_mme->plmn_Identity->mnc.list.count > 0) {
            /* Use first indicated PLMN MNC if it is defined */
            S1AP_NAS_FIRST_REQ (message_p).ue_identity.gummei.mnc = *r_mme->plmn_Identity->mnc.list.array[selected_plmn_identity];
            
            LOG_I(S1AP, "[eNB %d] Build S1AP_NAS_FIRST_REQ adding in s_TMSI: GUMMEI MNC %u ue %x\n",
              ctxt_pP->module_id,
              S1AP_NAS_FIRST_REQ (message_p).ue_identity.gummei.mnc,
              ue_context_pP->ue_context.rnti);
          }

        } else { // end if plmn_Identity != NULL
          S1AP_NAS_FIRST_REQ(message_p).ue_identity.gummei.mcc = rrc->configuration.mcc[selected_plmn_identity];
          S1AP_NAS_FIRST_REQ(message_p).ue_identity.gummei.mnc = rrc->configuration.mnc[selected_plmn_identity];
          S1AP_NAS_FIRST_REQ(message_p).ue_identity.gummei.mnc_len = rrc->configuration.mnc_digit_length[selected_plmn_identity];
        } // end else (plmn_Identity == NULL)

        S1AP_NAS_FIRST_REQ (message_p).ue_identity.gummei.mme_code     = BIT_STRING_to_uint8 (&r_mme->mmec);
        S1AP_NAS_FIRST_REQ (message_p).ue_identity.gummei.mme_group_id = BIT_STRING_to_uint16 (&r_mme->mmegi);

        MSC_LOG_TX_MESSAGE(MSC_S1AP_ENB,
          MSC_S1AP_MME,
          (const char *)&message_p->ittiMsg.s1ap_nas_first_req,
          sizeof(s1ap_nas_first_req_t),
          MSC_AS_TIME_FMT" S1AP_NAS_FIRST_REQ eNB %u UE %x",
          MSC_AS_TIME_ARGS(ctxt_pP),
          ctxt_pP->module_id,
          ctxt_pP->rnti);

        LOG_I(S1AP, "[eNB %d] Build S1AP_NAS_FIRST_REQ adding in s_TMSI: GUMMEI mme_code %u mme_group_id %u ue %x\n",
              ctxt_pP->module_id,
              S1AP_NAS_FIRST_REQ (message_p).ue_identity.gummei.mme_code,
              S1AP_NAS_FIRST_REQ (message_p).ue_identity.gummei.mme_group_id,
              ue_context_pP->ue_context.rnti);

      } // end if MME info present
    } // end "Fill UE identities with available information" sub-part

    itti_send_msg_to_task (TASK_S1AP, ctxt_pP->instance, message_p);
  }

#else

  {
    s1ap_eNB_new_data_request (
      ctxt_pP->module_id,
      ue_context_pP,
      rrcConnectionSetupComplete->dedicatedInfoNAS.
      buf,
      rrcConnectionSetupComplete->dedicatedInfoNAS.
      size);
  }

#endif
}

# if defined(ENABLE_ITTI)
//------------------------------------------------------------------------------
int
rrc_eNB_process_S1AP_DOWNLINK_NAS(
  MessageDef* msg_p,
  const char* msg_name,
  instance_t instance,
  mui_t* rrc_eNB_mui
)
//------------------------------------------------------------------------------
{
  uint16_t ue_initial_id;
  uint32_t eNB_ue_s1ap_id;
  uint32_t length;
  uint8_t *buffer;
  uint8_t srb_id; 
  
  struct rrc_eNB_ue_context_s* ue_context_p = NULL;
  protocol_ctxt_t              ctxt;
  ue_initial_id = S1AP_DOWNLINK_NAS (msg_p).ue_initial_id;
  eNB_ue_s1ap_id = S1AP_DOWNLINK_NAS (msg_p).eNB_ue_s1ap_id;
  ue_context_p = rrc_eNB_get_ue_context_from_s1ap_ids(instance, ue_initial_id, eNB_ue_s1ap_id);

  LOG_I(RRC, "[eNB %d] Received %s: ue_initial_id %d, eNB_ue_s1ap_id %d\n",
        instance,
        msg_name,
        ue_initial_id,
        eNB_ue_s1ap_id);

  if (ue_context_p == NULL) {

    MSC_LOG_RX_MESSAGE(
      MSC_RRC_ENB,
      MSC_S1AP_ENB,
      NULL,
      0,
      MSC_AS_TIME_FMT" DOWNLINK-NAS UE initial id %u eNB_ue_s1ap_id %u",
      0,0,//MSC_AS_TIME_ARGS(ctxt_pP),
      ue_initial_id,
      eNB_ue_s1ap_id);

    /* Can not associate this message to an UE index, send a failure to S1AP and discard it! */
    MessageDef *msg_fail_p;

    LOG_W(RRC, "[eNB %d] In S1AP_DOWNLINK_NAS: unknown UE from S1AP ids (%d, %d)\n", instance, ue_initial_id, eNB_ue_s1ap_id);

    msg_fail_p = itti_alloc_new_message (TASK_RRC_ENB, S1AP_NAS_NON_DELIVERY_IND);
    S1AP_NAS_NON_DELIVERY_IND (msg_fail_p).eNB_ue_s1ap_id = eNB_ue_s1ap_id;
    S1AP_NAS_NON_DELIVERY_IND (msg_fail_p).nas_pdu.length = S1AP_DOWNLINK_NAS (msg_p).nas_pdu.length;
    S1AP_NAS_NON_DELIVERY_IND (msg_fail_p).nas_pdu.buffer = S1AP_DOWNLINK_NAS (msg_p).nas_pdu.buffer;

    // TODO add failure cause when defined!


    MSC_LOG_TX_MESSAGE(
      MSC_RRC_ENB,
      MSC_S1AP_ENB,
      (const char *)NULL,
      0,
      MSC_AS_TIME_FMT" S1AP_NAS_NON_DELIVERY_IND UE initial id %u eNB_ue_s1ap_id %u (ue ctxt !found)",
      0,0,//MSC_AS_TIME_ARGS(ctxt_pP),
      ue_initial_id,
      eNB_ue_s1ap_id);

    itti_send_msg_to_task (TASK_S1AP, instance, msg_fail_p);
    return (-1);
  } else {
    PROTOCOL_CTXT_SET_BY_INSTANCE(&ctxt, instance, ENB_FLAG_YES, ue_context_p->ue_context.rnti, 0, 0);

    srb_id = ue_context_p->ue_context.Srb2.Srb_info.Srb_id;
  

    /* Is it the first income from S1AP ? */
    if (ue_context_p->ue_context.eNB_ue_s1ap_id == 0) {
      ue_context_p->ue_context.eNB_ue_s1ap_id = S1AP_DOWNLINK_NAS (msg_p).eNB_ue_s1ap_id;
    }

    MSC_LOG_RX_MESSAGE(
      MSC_RRC_ENB,
      MSC_S1AP_ENB,
      (const char *)NULL,
      0,
      MSC_AS_TIME_FMT" DOWNLINK-NAS UE initial id %u eNB_ue_s1ap_id %u",
      0,0,//MSC_AS_TIME_ARGS(ctxt_pP),
      ue_initial_id,
      S1AP_DOWNLINK_NAS (msg_p).eNB_ue_s1ap_id);


    /* Create message for PDCP (DLInformationTransfer_t) */
    length = do_DLInformationTransfer (
               instance,
               &buffer,
               rrc_eNB_get_next_transaction_identifier (instance),
               S1AP_DOWNLINK_NAS (msg_p).nas_pdu.length,
               S1AP_DOWNLINK_NAS (msg_p).nas_pdu.buffer);

    LOG_DUMPMSG(RRC,DEBUG_RRC,buffer,length,"[MSG] RRC DL Information Transfer\n");

    /* 
     * switch UL or DL NAS message without RRC piggybacked to SRB2 if active. 
     */
    /* Transfer data to PDCP */
    rrc_data_req (
		  &ctxt,
		  srb_id,
		  *rrc_eNB_mui++,
		  SDU_CONFIRM_NO,
		  length,
		  buffer,
		  PDCP_TRANSMISSION_MODE_CONTROL);
    
    return (0);
  }
}

/*------------------------------------------------------------------------------*/
int rrc_eNB_process_S1AP_INITIAL_CONTEXT_SETUP_REQ(MessageDef *msg_p, const char *msg_name, instance_t instance)
{
  uint16_t                        ue_initial_id;