Implementation of UE context release command JIRA ID = ODUHIGH-330
[o-du/l2.git] / src / du_app / du_f1ap_msg_hdl.c
index e38e331..4975304 100644 (file)
 #include "UPTransportLayerInformation.h"
 #include "GTPTunnel.h"
 
-DuCfgParams duCfgParam;
+#ifdef O1_ENABLE
+
+#include "Config.h"
+extern StartupConfig g_cfg;
+
+#endif
 
+DuCfgParams duCfgParam;
 /************************************************************************
  *
  * @brief Converts enum values into actual value of Poll retransmit timer
@@ -174,9 +180,9 @@ uint16_t getPollRetxTmr(uint8_t pollRetxTmrCfg)
  * @return Actual value of pollPdu
  *
  * ****************************************************************/
-int16_t getPollPdu(uint8_t pollPduCfg)
+int32_t getPollPdu(uint8_t pollPduCfg)
 {
-   int16_t pollPdu;
+   int32_t pollPdu;
    switch(pollPduCfg)
    {
       case PollPDU_p4:
@@ -1091,16 +1097,15 @@ uint8_t BuildServedCellList(GNB_DU_Served_Cells_List_t *duServedCell)
       return RFAILED;
    }
    /* MIB */
-   srvCellItem->gNB_DU_System_Information->mIB_message.size =\
-                                                            strlen(( char *)duCfgParam.srvdCellLst[0].duSysInfo.mibMsg);
+   srvCellItem->gNB_DU_System_Information->mIB_message.size = duCfgParam.srvdCellLst[0].duSysInfo.mibLen;
    DU_ALLOC(srvCellItem->gNB_DU_System_Information->mIB_message.buf,
         srvCellItem->gNB_DU_System_Information->mIB_message.size);
    if(!srvCellItem->gNB_DU_System_Information->mIB_message.buf)
    {
       return RFAILED;
    }
-   strcpy((char *)srvCellItem->gNB_DU_System_Information->mIB_message.buf,
-        (char *)duCfgParam.srvdCellLst[0].duSysInfo.mibMsg);
+   memcpy(srvCellItem->gNB_DU_System_Information->mIB_message.buf, duCfgParam.srvdCellLst[0].duSysInfo.mibMsg, \
+                  srvCellItem->gNB_DU_System_Information->mIB_message.size);
 
    /* SIB1 */
    srvCellItem->gNB_DU_System_Information->sIB1_message.size =\
@@ -1197,7 +1202,7 @@ uint8_t BuildRrcVer(RRC_Version_t *rrcVer)
  *
  * @details
  *
- *    Function : SendF1APMsg
+ *    Function : sendF1APMsg
  *
  *    Functionality: Sends F1 msg over SCTP
  *
@@ -1207,11 +1212,11 @@ uint8_t BuildRrcVer(RRC_Version_t *rrcVer)
  *         RFAILED - failure
  *
  * ****************************************************************/
-uint8_t SendF1APMsg(Region region, Pool pool)
+uint8_t sendF1APMsg()
 {
    Buffer *mBuf = NULLP;
   
-   if(ODU_GET_MSG_BUF(region, pool, &mBuf) == ROK)
+   if(ODU_GET_MSG_BUF(DU_APP_MEM_REGION, DU_POOL, &mBuf) == ROK)
    {
       if(ODU_ADD_POST_MSG_MULT((Data *)encBuf, encBufSize, mBuf) == ROK)
       {
@@ -1238,7 +1243,7 @@ uint8_t SendF1APMsg(Region region, Pool pool)
       return RFAILED;
    }
    return ROK; 
-} /* SendF1APMsg */
+} /* sendF1APMsg */
 
 /*******************************************************************
  *
@@ -1690,7 +1695,7 @@ uint8_t BuildAndSendF1SetupReq()
       }
 
       /* Sending msg */
-      if(SendF1APMsg(DU_APP_MEM_REGION, DU_POOL) != ROK)
+      if(sendF1APMsg() != ROK)
       {
         DU_LOG("\nERROR  -->  F1AP : Sending F1 Setup request failed");
         break;
@@ -2493,7 +2498,7 @@ uint8_t BuildAndSendDUConfigUpdate()
         }
       }
       /* Sending msg */
-      if(SendF1APMsg(DU_APP_MEM_REGION, DU_POOL) != ROK)
+      if(sendF1APMsg() != ROK)
       {
         DU_LOG("\nERROR  -->  F1AP : Sending GNB-DU Config Update failed");
         break;
@@ -2697,7 +2702,7 @@ uint8_t BuildAndSendULRRCMessageTransfer(DuUeCb  ueCb, uint8_t lcId, \
       }
 
       /* Sending  msg  */
-      if(SendF1APMsg(DU_APP_MEM_REGION,DU_POOL)        !=      ROK)
+      if(sendF1APMsg() !=      ROK)
       {
         DU_LOG("\nERROR  -->   F1AP : Sending  UL RRC Message Transfer Failed");
         break;
@@ -5894,7 +5899,7 @@ uint8_t BuildAndSendInitialRrcMsgTransfer(uint32_t gnbDuUeF1apId, uint16_t crnti
         }
       }
       /* Sending  msg  */
-      if(SendF1APMsg(DU_APP_MEM_REGION,DU_POOL) != ROK)
+      if(sendF1APMsg() != ROK)
       {
         DU_LOG("\nERROR  -->  F1AP : Sending Initial UL RRC Message Transfer Failed");
         ret = RFAILED;
@@ -7167,7 +7172,11 @@ uint8_t extractUpTnlInfo(uint8_t drbId, uint8_t configType,\
 
    upTnlInfo->drbId = drbId; 
    upTnlInfo->configType = configType;
+#ifdef O1_ENABLE
+   cmInetAddr((S8*)g_cfg.DU_IPV4_Addr, &ipv4_du);
+#else
    cmInetAddr((char *)DU_IP_V4_ADDR, &ipv4_du);
+#endif
 
    for(tnlIdx=0; tnlIdx < tnlInfo->list.count; tnlIdx++)
    {
@@ -8789,79 +8798,82 @@ uint8_t extractUeReCfgCellInfo(CellGroupConfigRrc_t *cellGrp, MacUeCfg *macUeCfg
       /* Fill MacCell Group Reconfig  */
       if(cellGrp->mac_CellGroupConfig)
       {
+         macUeCfg->macCellGrpCfgPres = true;
          macCellGroup = ((MAC_CellGroupConfig_t *)(cellGrp->mac_CellGroupConfig));
          if(macCellGroup->schedulingRequestConfig)
-        {
+         {
             extractSchReqReConfig(macCellGroup->schedulingRequestConfig, &macUeCfg->macCellGrpCfg.schReqCfg);
-        }
+         }
          if(macCellGroup->tag_Config)
-        {
+         {
             extractTagReconfig(macCellGroup->tag_Config, &macUeCfg->macCellGrpCfg.tagCfg);
-        }
-        if(macCellGroup->bsr_Config)
-        {
+         }
+         if(macCellGroup->bsr_Config)
+         {
             macUeCfg->macCellGrpCfg.bsrTmrCfg.periodicTimer = macCellGroup->bsr_Config->periodicBSR_Timer;
             macUeCfg->macCellGrpCfg.bsrTmrCfg.retxTimer     = macCellGroup->bsr_Config->retxBSR_Timer;
-           if(macCellGroup->bsr_Config->logicalChannelSR_DelayTimer)
-           {
+            if(macCellGroup->bsr_Config->logicalChannelSR_DelayTimer)
+            {
                macUeCfg->macCellGrpCfg.bsrTmrCfg.srDelayTimer  =\
-                 *(macCellGroup->bsr_Config->logicalChannelSR_DelayTimer);
-           }
-        }
-        if(macCellGroup->phr_Config)
-        {
-           if(macCellGroup->phr_Config->present == MAC_CellGroupConfig__phr_Config_PR_setup)
-           {
+               *(macCellGroup->bsr_Config->logicalChannelSR_DelayTimer);
+            }
+         }
+         if(macCellGroup->phr_Config)
+         {
+            if(macCellGroup->phr_Config->present == MAC_CellGroupConfig__phr_Config_PR_setup)
+            {
                macUeCfg->macCellGrpCfg.phrCfgSetupPres = true;
                if(macCellGroup->phr_Config->choice.setup)
-              {
-                macUeCfg->macCellGrpCfg.phrCfg.periodicTimer     = \
-                  macCellGroup->phr_Config->choice.setup->phr_PeriodicTimer;
-                macUeCfg->macCellGrpCfg.phrCfg.prohibitTimer     = \
-                  macCellGroup->phr_Config->choice.setup->phr_ProhibitTimer;
-                macUeCfg->macCellGrpCfg.phrCfg.txPowerFactor     = \
-                  macCellGroup->phr_Config->choice.setup->phr_Tx_PowerFactorChange;
-                macUeCfg->macCellGrpCfg.phrCfg.multiplePHR       = \
-                  macCellGroup->phr_Config->choice.setup->multiplePHR;
-                macUeCfg->macCellGrpCfg.phrCfg.dummy             = \
-                  macCellGroup->phr_Config->choice.setup->dummy;
-                macUeCfg->macCellGrpCfg.phrCfg.phrType2OtherCell = \
-                  macCellGroup->phr_Config->choice.setup->phr_Type2OtherCell;
-                macUeCfg->macCellGrpCfg.phrCfg.phrOtherCG        = \
-                  macCellGroup->phr_Config->choice.setup->phr_ModeOtherCG;
-              }
-           }
-        }
+               {
+                  macUeCfg->macCellGrpCfg.phrCfg.periodicTimer     = \
+                  macCellGroup->phr_Config->choice.setup->phr_PeriodicTimer;
+                  macUeCfg->macCellGrpCfg.phrCfg.prohibitTimer     = \
+                  macCellGroup->phr_Config->choice.setup->phr_ProhibitTimer;
+                  macUeCfg->macCellGrpCfg.phrCfg.txPowerFactor     = \
+                  macCellGroup->phr_Config->choice.setup->phr_Tx_PowerFactorChange;
+                  macUeCfg->macCellGrpCfg.phrCfg.multiplePHR       = \
+                  macCellGroup->phr_Config->choice.setup->multiplePHR;
+                  macUeCfg->macCellGrpCfg.phrCfg.dummy             = \
+                  macCellGroup->phr_Config->choice.setup->dummy;
+                  macUeCfg->macCellGrpCfg.phrCfg.phrType2OtherCell = \
+                  macCellGroup->phr_Config->choice.setup->phr_Type2OtherCell;
+                  macUeCfg->macCellGrpCfg.phrCfg.phrOtherCG        = \
+                  macCellGroup->phr_Config->choice.setup->phr_ModeOtherCG;
+               }
+            }
+         }
       }
       /* Fill Physical Cell Group Reconfig */
       if(cellGrp->physicalCellGroupConfig)
       {
+         macUeCfg->phyCellGrpCfgPres = true;
          phyCellGrpCfg = ((PhysicalCellGroupConfig_t *)(cellGrp->physicalCellGroupConfig));
          if(phyCellGrpCfg->p_NR_FR1)
-        {
-           if(*(phyCellGrpCfg->p_NR_FR1) != macUeCfg->phyCellGrpCfg.pNrFr1)
+         {
+            if(*(phyCellGrpCfg->p_NR_FR1) != macUeCfg->phyCellGrpCfg.pNrFr1)
                macUeCfg->phyCellGrpCfg.pNrFr1 = *(phyCellGrpCfg->p_NR_FR1);
-        }
+         }
          macUeCfg->phyCellGrpCfg.pdschHarqAckCodebook = phyCellGrpCfg->pdsch_HARQ_ACK_Codebook;
       }
       /* Fill SpCell Reconfig */
       if(cellGrp->spCellConfig)
       {
+         macUeCfg->spCellCfgPres = true;
          spcellCfg = ((SpCellConfig_t *)(cellGrp->spCellConfig));  
          if(spcellCfg->servCellIndex)
-        {
+         {
             macUeCfg->spCellCfg.servCellIdx = *(spcellCfg->servCellIndex);
-        }
+         }
          /* Fill Serving cell Reconfig info */
-        if(cellGrp->spCellConfig->spCellConfigDedicated)
-        {
-           servCellCfg = ((ServingCellConfig_t *)(cellGrp->spCellConfig->spCellConfigDedicated));
+         if(cellGrp->spCellConfig->spCellConfigDedicated)
+         {
+            servCellCfg = ((ServingCellConfig_t *)(cellGrp->spCellConfig->spCellConfigDedicated));
             ret = extractSpCellDedicatedCfg(servCellCfg, &macUeCfg->spCellCfg.servCellCfg);
-           if(ret == RFAILED)
-           {
-              DU_LOG("\nERROR --> F1AP : Failed at extractSpCellDedicatedCfg()");
-           }
-        }
+            if(ret == RFAILED)
+            {
+               DU_LOG("\nERROR --> F1AP : Failed at extractSpCellDedicatedCfg()");
+            }
+         }
       }
    }
    return ret;
@@ -9279,7 +9291,7 @@ uint8_t procUeReCfgCellInfo(MacUeCfg *macUeCfg, void *cellInfo)
  * ****************************************************************/
 void duFillModulationDetails(MacUeCfg *ueCfg, MacUeCfg *oldUeCfg, void *ueCap)
 {
-   UE_NR_Capability_t *ueNrCap;
+   UE_NR_Capability_t *ueNrCap=NULLP;
 
    if(ueCap)
       ueNrCap = (UE_NR_Capability_t *)ueCap;
@@ -10005,6 +10017,7 @@ uint8_t procF1UeContextSetupReq(F1AP_PDU_t *f1apMsg)
                }
                else
                {
+                  duUeCb->f1UeDb->dlRrcMsgPres = true;
                   memset(duUeCb->f1UeDb->dlRrcMsg, 0, sizeof(F1DlRrcMsg));
                   ret = extractDlRrcMsg(gnbDuUeF1apId, gnbCuUeF1apId, duUeCb->f1UeDb->dlRrcMsg,\
                         &ueSetReq->protocolIEs.list.array[ieIdx]->value.choice.RRCContainer);
@@ -10577,7 +10590,7 @@ uint8_t BuildAndSendUeContextSetupRsp(uint8_t ueIdx, uint8_t cellId)
       }
 
       /* Sending  msg  */
-      if(SendF1APMsg(DU_APP_MEM_REGION,DU_POOL)        != ROK)
+      if(sendF1APMsg() != ROK)
       {
         DU_LOG("\nERROR  -->  F1AP : Sending UE Context Setup Response failed");
         ret = RFAILED;
@@ -10779,7 +10792,7 @@ uint8_t BuildAndSendF1ResetReq()
         }
       }
 
-      if(SendF1APMsg(DU_APP_MEM_REGION, DU_POOL) != ROK)
+      if(sendF1APMsg() != ROK)
       {
         DU_LOG("\nERROR  -->  F1AP : Sending F1 Reset request failed");
         break;
@@ -10932,7 +10945,7 @@ uint8_t BuildAndSendF1ResetAck()
         }
       }
       /* Sending msg */
-      if(SendF1APMsg(DU_APP_MEM_REGION, DU_POOL) != ROK)
+      if(sendF1APMsg() != ROK)
       {
         DU_LOG("\nERROR  -->  F1AP : Sending F1 Reset Acknowledgement failed");
         break;
@@ -11199,7 +11212,7 @@ uint8_t BuildAndSendRrcDeliveryReport(uint32_t gnbCuUeF1apId, \
       }
 
       /* Sending msg */
-      if(SendF1APMsg(DU_APP_MEM_REGION, DU_POOL) != ROK)
+      if(sendF1APMsg() != ROK)
       {
         DU_LOG("\nERROR  -->  F1AP : Sending RRC delivery  msg request failed");
         break;
@@ -11927,7 +11940,7 @@ uint8_t BuildAndSendUeContextModResp(uint8_t ueIdx, uint8_t cellId)
       }
 
       /* Sending  msg  */
-      if(SendF1APMsg(DU_APP_MEM_REGION,DU_POOL) != ROK)
+      if(sendF1APMsg() != ROK)
       {
          DU_LOG("\nERROR  -->  F1AP : Sending UE Context Setup Res Failed");
          ret = RFAILED;
@@ -11937,7 +11950,6 @@ uint8_t BuildAndSendUeContextModResp(uint8_t ueIdx, uint8_t cellId)
    }
    FreeUeContextModResp(f1apMsg);
    return ret;
-
 }
 /*******************************************************************
  *
@@ -12273,6 +12285,436 @@ uint8_t procF1UeContextModificationReq(F1AP_PDU_t *f1apMsg)
    return ret; 
 }
 /*****************************************************************i
+*
+* @brief Free memory allocated for UE Context Release Request
+*
+* @details
+*
+*    Function : FreeUeContextReleaseReq
+*
+*    Functionality:
+*         - Free memory allocated for UE Context Release Request
+*
+* @params[in] F1AP_PDU_t *f1apMsg
+* @return void 
+*
+* *************************************************************/
+void FreeUeContextReleaseReq(F1AP_PDU_t *f1apMsg)
+{
+   uint8_t ieIdx;
+   UEContextReleaseRequest_t *ueReleaseReq = NULLP;
+   
+   if(f1apMsg)
+   {
+      if(f1apMsg->choice.initiatingMessage)
+      {
+         ueReleaseReq =&f1apMsg->choice.initiatingMessage->value.choice.UEContextReleaseRequest;
+         if(ueReleaseReq->protocolIEs.list.array)
+         {
+            for(ieIdx=0 ; ieIdx<ueReleaseReq->protocolIEs.list.count; ieIdx++)
+            {
+               DU_FREE(ueReleaseReq->protocolIEs.list.array[ieIdx], sizeof(UEContextReleaseRequest_t));
+            }
+            DU_FREE(ueReleaseReq->protocolIEs.list.array, ueReleaseReq->protocolIEs.list.size);
+         }
+         DU_FREE(f1apMsg->choice.initiatingMessage, sizeof(InitiatingMessage_t));
+      }
+      DU_FREE(f1apMsg, sizeof(F1AP_PDU_t));
+   }
+
+}
+/*****************************************************************i
+*
+* @brief Build and Send UE Context Release Request  
+*
+* @details
+*
+*    Function : BuildAndSendUeContextReleaseReq
+*
+*    Functionality:
+*         - Build and Send UE Context Release Request 
+*
+* @params[in]
+* @return ROK     - success
+*         RFAILED - failure
+*
+* *************************************************************/
+uint8_t BuildAndSendUeContextReleaseReq(uint16_t cellId, uint8_t ueIdx)
+{
+   bool memAllocFail = false;
+   uint8_t ieIdx =0;
+   uint8_t ret = RFAILED;
+   uint16_t cellIdx =0;
+   uint16_t crnti = 0;
+   uint8_t  elementCnt = 0;
+   uint32_t  gnbCuUeF1apId =0;   /* gNB-CU UE F1AP Id */
+   uint32_t  gnbDuUeF1apId =0;   /* gNB-DU UE F1AP Id */
+   asn_enc_rval_t encRetVal; 
+   F1AP_PDU_t *f1apMsg = NULLP;
+   UEContextReleaseRequest_t *ueReleaseReq = NULLP;
+
+   DU_LOG("\nINFO  --> Building the UE Context Release Request");
+   do
+   {
+      DU_ALLOC(f1apMsg, sizeof(F1AP_PDU_t));
+      if(f1apMsg == NULLP)
+      {
+         DU_LOG("\nERROR  -->  F1AP : BuildAndSendUeContextReleaseReq(): Memory allocation failed for f1apMsg");
+         break;
+      }
+
+      f1apMsg->present = F1AP_PDU_PR_initiatingMessage;
+      DU_ALLOC(f1apMsg->choice.initiatingMessage, sizeof(InitiatingMessage_t));
+      if(f1apMsg->choice.initiatingMessage == NULLP)
+      {
+         DU_LOG("\nERROR  -->  F1AP : BuildAndSendUeContextReleaseReq(): Memory allocation failed for\
+         initiatingMessage");   
+         break;
+      }
+      f1apMsg->choice.initiatingMessage->procedureCode = ProcedureCode_id_UEContextReleaseRequest;
+      f1apMsg->choice.initiatingMessage->criticality = Criticality_reject;
+      f1apMsg->choice.initiatingMessage->value.present = \
+      InitiatingMessage__value_PR_UEContextReleaseRequest;
+
+      ueReleaseReq = &f1apMsg->choice.initiatingMessage->value.choice.UEContextReleaseRequest;
+
+      elementCnt = 2;
+
+      ueReleaseReq->protocolIEs.list.count = elementCnt;
+      ueReleaseReq->protocolIEs.list.size = elementCnt * sizeof(UEContextReleaseRequest_t *);
+
+      /* Initialize the F1Setup members */
+      DU_ALLOC(ueReleaseReq->protocolIEs.list.array,ueReleaseReq->protocolIEs.list.size);
+      if(ueReleaseReq->protocolIEs.list.array == NULLP)
+      {
+         DU_LOG("\nERROR  -->  F1AP : BuildAndSendUeContextReleaseReq(): Memory allocation failed for IE array");
+         break;
+      }
+      for(ieIdx=0; ieIdx<elementCnt; ieIdx++)
+      {
+         DU_ALLOC(ueReleaseReq->protocolIEs.list.array[ieIdx],\
+               sizeof(UEContextReleaseRequest_t));
+         if(ueReleaseReq->protocolIEs.list.array[ieIdx] == NULLP)
+         {
+            DU_LOG("\nERROR  -->  F1AP : BuildAndSendUeContextReleaseReq(): Memory allocation failed for IE elements");
+            memAllocFail = true;  
+            break;
+         }
+      }
+      if(memAllocFail == true)
+         break;
+
+      /* Fetching Ue Cb Info*/
+      GET_CELL_IDX(cellId, cellIdx);
+      if(duCb.actvCellLst[cellIdx] == NULLP)
+      {
+         DU_LOG("\nERROR  -->  F1AP : BuildAndSendUeContextReleaseReq(): CellId[%d] does not exist", cellId);
+         break;
+      }
+      else
+      {
+         GET_CRNTI(crnti, ueIdx);
+         if(duCb.actvCellLst[cellIdx]->ueCb[ueIdx-1].crnti != crnti)
+         {
+            DU_LOG("\nERROR  -->  F1AP : BuildAndSendUeContextReleaseReq(): crnti[%d] does not exist", crnti);
+            break;
+         }
+         gnbDuUeF1apId = duCb.actvCellLst[cellIdx]->ueCb[ueIdx-1].gnbDuUeF1apId;
+         gnbCuUeF1apId = duCb.actvCellLst[cellIdx]->ueCb[ueIdx-1].gnbCuUeF1apId;
+      }
+
+      ieIdx=0; 
+      ueReleaseReq->protocolIEs.list.array[ieIdx]->id = ProtocolIE_ID_id_gNB_CU_UE_F1AP_ID; 
+      ueReleaseReq->protocolIEs.list.array[ieIdx]->criticality= Criticality_reject;
+      ueReleaseReq->protocolIEs.list.array[ieIdx]->value.present = \
+      UEContextReleaseRequestIEs__value_PR_GNB_CU_UE_F1AP_ID;
+      ueReleaseReq->protocolIEs.list.array[ieIdx]->value.choice.GNB_CU_UE_F1AP_ID =gnbCuUeF1apId;
+      
+      ieIdx++;
+      ueReleaseReq->protocolIEs.list.array[ieIdx]->id = ProtocolIE_ID_id_gNB_DU_UE_F1AP_ID;
+      ueReleaseReq->protocolIEs.list.array[ieIdx]->criticality= Criticality_reject;
+      ueReleaseReq->protocolIEs.list.array[ieIdx]->value.present =\
+      UEContextReleaseRequestIEs__value_PR_GNB_DU_UE_F1AP_ID;
+      ueReleaseReq->protocolIEs.list.array[ieIdx]->value.choice.GNB_DU_UE_F1AP_ID =gnbDuUeF1apId;
+      
+      xer_fprint(stdout, &asn_DEF_F1AP_PDU, f1apMsg);
+
+      /* Encode the F1SetupRequest type as APER */
+      memset(encBuf, 0, ENC_BUF_MAX_LEN);
+      encBufSize = 0;
+      encRetVal = aper_encode(&asn_DEF_F1AP_PDU, 0, f1apMsg, PrepFinalEncBuf, encBuf);
+      /* Encode results */
+      if(encRetVal.encoded == ENCODE_FAIL)
+      {
+         DU_LOG("\nERROR  -->  F1AP : Could not encode UEContextReleaseRequest structure (at %s)\n",\
+               encRetVal.failed_type ? encRetVal.failed_type->name : "unknown");
+         break;
+      }
+      else
+      {
+         DU_LOG("\nDEBUG   -->  F1AP : Created APER encoded buffer for UEContextReleaseRequest\n");
+         for(ieIdx=0; ieIdx< encBufSize; ieIdx++)
+         {
+            printf("%x",encBuf[ieIdx]);
+         }
+      }
+
+      /* Sending msg */
+      if(sendF1APMsg() != ROK)
+      {
+         DU_LOG("\nERROR  -->  F1AP : Sending UE Context Release Request failed");
+         break;
+      }
+      ret = ROK;
+      break;
+   }while(true);
+
+   FreeUeContextReleaseReq(f1apMsg);
+   return ret;
+}
+/*****************************************************************i
+ *
+ * @brief Free memory allocated for UE Context Release Complete
+ *
+ * @details
+ *
+ *    Function : FreeUeContextReleaseComplete
+ *
+ *    Functionality:
+ *         - Free memory allocated for UE Context Release Complete
+ *
+ * @params[in] F1AP_PDU_t *f1apMsg
+ * @return void
+ *
+ * *************************************************************/
+void FreeUeContextReleaseComplete(F1AP_PDU_t *f1apMsg)
+{
+   uint8_t ieIdx;
+   UEContextReleaseComplete_t *ueReleaseComplete = NULLP;
+
+   if(f1apMsg)
+   {
+      if(f1apMsg->choice.successfulOutcome)
+      {
+         ueReleaseComplete =&f1apMsg->choice.successfulOutcome->value.choice.UEContextReleaseComplete;
+         if(ueReleaseComplete->protocolIEs.list.array)
+         {
+            for(ieIdx=0 ; ieIdx<ueReleaseComplete->protocolIEs.list.count; ieIdx++)
+            {
+               DU_FREE(ueReleaseComplete->protocolIEs.list.array[ieIdx], sizeof(UEContextReleaseComplete_t));
+            }
+            DU_FREE(ueReleaseComplete->protocolIEs.list.array, ueReleaseComplete->protocolIEs.list.size);
+         }
+         DU_FREE(f1apMsg->choice.successfulOutcome, sizeof(SuccessfulOutcome_t));
+      }
+      DU_FREE(f1apMsg, sizeof(F1AP_PDU_t));
+   }
+
+}
+/*****************************************************************i
+ *
+ * @brief Build and Send UE Context Release Complete
+ *
+ * @details
+ *
+ *    Function : BuildAndSendUeContextReleaseComplete
+ *
+ *    Functionality:
+ *         - Build and Send UE Context Release Complete
+ *
+ * @params[in]
+ * @return ROK     - success
+ *         RFAILED - failure
+ *
+ * *************************************************************/
+uint8_t BuildAndSendUeContextReleaseComplete(uint32_t  gnbCuUeF1apId, uint32_t  gnbDuUeF1apId)
+{
+   bool memAllocFail = false;
+   uint8_t ieIdx =0, ret = RFAILED, elementCnt = 0;
+   asn_enc_rval_t encRetVal;
+   F1AP_PDU_t *f1apMsg = NULLP;
+   UEContextReleaseComplete_t *ueReleaseComplete = NULLP;
+
+   DU_LOG("\nINFO  --> Building the UE Context Release Complete");
+   do
+   {
+      DU_ALLOC(f1apMsg, sizeof(F1AP_PDU_t));
+      if(f1apMsg == NULLP)
+      {
+         DU_LOG("\nERROR  -->  F1AP : BuildAndSendUeContextReleaseComplete(): Memory allocation failed for f1apMsg");
+         break;
+      }
+
+      f1apMsg->present = F1AP_PDU_PR_successfulOutcome;
+      DU_ALLOC(f1apMsg->choice.successfulOutcome, sizeof(SuccessfulOutcome_t));
+      if(f1apMsg->choice.successfulOutcome == NULLP)
+      {
+         DU_LOG("\nERROR  -->  F1AP : BuildAndSendUeContextReleaseComplete(): Memory allocation failed for\
+               successfulOutcome");
+         break;
+      }
+      f1apMsg->choice.successfulOutcome->procedureCode = ProcedureCode_id_UEContextRelease;
+      f1apMsg->choice.successfulOutcome->criticality = Criticality_reject;
+      f1apMsg->choice.successfulOutcome->value.present = \
+      SuccessfulOutcome__value_PR_UEContextReleaseComplete;
+
+      ueReleaseComplete = &f1apMsg->choice.successfulOutcome->value.choice.UEContextReleaseComplete;
+
+      elementCnt = 2;
+      ueReleaseComplete->protocolIEs.list.count = elementCnt;
+      ueReleaseComplete->protocolIEs.list.size = elementCnt * sizeof(UEContextReleaseComplete_t *);
+
+      /* Initialize the UE Release Complete members */
+      DU_ALLOC(ueReleaseComplete->protocolIEs.list.array,ueReleaseComplete->protocolIEs.list.size);
+      if(ueReleaseComplete->protocolIEs.list.array == NULLP)
+      {
+         DU_LOG("\nERROR  -->  F1AP : BuildAndSendUeContextReleaseComplete(): Memory allocation failed for IE array");
+         break;
+      }
+      for(ieIdx=0; ieIdx<elementCnt; ieIdx++)
+      {
+         DU_ALLOC(ueReleaseComplete->protocolIEs.list.array[ieIdx],\
+               sizeof(UEContextReleaseComplete_t));
+         if(ueReleaseComplete->protocolIEs.list.array[ieIdx] == NULLP)
+         {
+            DU_LOG("\nERROR  -->  F1AP : BuildAndSendUeContextReleaseComplete(): Memory allocation failed for IE\
+            elements");
+            memAllocFail = true;
+            break;
+         }
+      }
+      if(memAllocFail == true)
+         break;
+
+
+      ieIdx=0;
+      ueReleaseComplete->protocolIEs.list.array[ieIdx]->id = ProtocolIE_ID_id_gNB_CU_UE_F1AP_ID;
+      ueReleaseComplete->protocolIEs.list.array[ieIdx]->criticality= Criticality_reject;
+      ueReleaseComplete->protocolIEs.list.array[ieIdx]->value.present = \
+      UEContextReleaseCompleteIEs__value_PR_GNB_CU_UE_F1AP_ID;
+      ueReleaseComplete->protocolIEs.list.array[ieIdx]->value.choice.GNB_CU_UE_F1AP_ID =gnbCuUeF1apId;
+
+      ieIdx++;
+      ueReleaseComplete->protocolIEs.list.array[ieIdx]->id = ProtocolIE_ID_id_gNB_DU_UE_F1AP_ID;
+      ueReleaseComplete->protocolIEs.list.array[ieIdx]->criticality= Criticality_reject;
+      ueReleaseComplete->protocolIEs.list.array[ieIdx]->value.present =\
+      UEContextReleaseCompleteIEs__value_PR_GNB_DU_UE_F1AP_ID;
+      ueReleaseComplete->protocolIEs.list.array[ieIdx]->value.choice.GNB_DU_UE_F1AP_ID =gnbDuUeF1apId;
+
+      xer_fprint(stdout, &asn_DEF_F1AP_PDU, f1apMsg);
+
+      /* Encode the F1SetupComplete type as APER */
+      memset(encBuf, 0, ENC_BUF_MAX_LEN);
+      encBufSize = 0;
+      encRetVal = aper_encode(&asn_DEF_F1AP_PDU, 0, f1apMsg, PrepFinalEncBuf, encBuf);
+      /* Encode results */
+      if(encRetVal.encoded == ENCODE_FAIL)
+      {
+         DU_LOG("\nERROR  -->  F1AP : Could not encode UEContextReleaseComplete structure (at %s)\n",\
+               encRetVal.failed_type ? encRetVal.failed_type->name : "unknown");
+         break;
+      }
+      else
+      {
+         DU_LOG("\nDEBUG   -->  F1AP : Created APER encoded buffer for UEContextReleaseComplete\n");
+         for(ieIdx=0; ieIdx< encBufSize; ieIdx++)
+         {
+            printf("%x",encBuf[ieIdx]);
+         }
+      }
+
+      /* Sending msg */
+      if(sendF1APMsg() != ROK)
+      {
+         DU_LOG("\nERROR  -->  F1AP : Sending UE Context Release Complete failed");
+         break;
+      }
+      ret = ROK;
+      break;
+   }while(true);
+
+   FreeUeContextReleaseComplete(f1apMsg);
+   return ret;
+
+   /*TODO: To add trigger for UE context release complete, once the operations of UE context
+    * release command are done*/
+}
+/*******************************************************************
+*
+* @brief added free part for the memory allocated by aper_decoder 
+*
+* @details
+*
+*    Function : freeAperDecodeUeContextReleaseCommand 
+*
+*    Functionality: added free part for the memory allocated by aper_decoder
+*
+* @params[in] F1AP_PDU_t *f1apMsg
+* @return void
+*
+* ****************************************************************/
+void freeAperDecodeUeContextReleaseCommand(F1AP_PDU_t *f1apMsg)
+{
+   uint8_t ieIdx=0;
+   UEContextReleaseCommand_t *ueContextReleaseCommand = NULLP;
+
+   ueContextReleaseCommand = &f1apMsg->choice.initiatingMessage->value.choice.UEContextReleaseCommand;
+   
+   if(ueContextReleaseCommand->protocolIEs.list.array)
+   {
+      for(ieIdx=0; ieIdx < ueContextReleaseCommand->protocolIEs.list.count; ieIdx++)
+      {
+         if(ueContextReleaseCommand->protocolIEs.list.array[ieIdx])
+         {
+            switch(ueContextReleaseCommand->protocolIEs.list.array[ieIdx]->id)
+            {
+               case ProtocolIE_ID_id_gNB_CU_UE_F1AP_ID:
+                  break;
+               case ProtocolIE_ID_id_gNB_DU_UE_F1AP_ID:
+                  break;
+               case ProtocolIE_ID_id_Cause:
+                  break;
+               case ProtocolIE_ID_id_RRCContainer:
+               {
+                  if(ueContextReleaseCommand->protocolIEs.list.array[ieIdx]->value.choice.RRCContainer.buf)
+                  {
+                     free(ueContextReleaseCommand->protocolIEs.list.array[ieIdx]->value.choice.RRCContainer.buf);
+                  }
+                  break;
+               }
+               default :
+                  DU_LOG("\nERROR  -->  F1AP: freeAperDecodeUeContextReleaseCommand():Invalid IE Received: %ld"\
+                       ,ueContextReleaseCommand->protocolIEs.list.array[ieIdx]->id);
+                  break;
+            }
+         }
+         free(ueContextReleaseCommand->protocolIEs.list.array[ieIdx]);
+      }
+      free(ueContextReleaseCommand->protocolIEs.list.array);
+   }
+}
+/*******************************************************************
+*
+* @brief processing of UE Context Release Command
+*
+* @details
+*
+*    Function : procF1UeContextReleaseCommand 
+*
+*    Functionality: processing of UE Context Release Command
+*
+* @params[in] F1AP_PDU_t *f1apMsg
+* @return void
+*
+* ****************************************************************/
+uint8_t procF1UeContextReleaseCommand(F1AP_PDU_t *f1apMsg)
+{
+   /*TODO: processing of DL RRC Msg Transfer to RLC->SCH->MAC-LOWER-MAC->PHY, if RRC container is received */
+   
+   freeAperDecodeUeContextReleaseCommand(f1apMsg);
+   return ROK;
+}
+/**************************************************************
  *
  * @brief Handles received F1AP message and sends back response  
  *
@@ -12396,6 +12838,11 @@ void F1APMsgHdlr(Buffer *mBuf)
                      procF1UeContextModificationReq(f1apMsg);
                      break;
                   }
+               case InitiatingMessage__value_PR_UEContextReleaseCommand:
+                  {
+                      procF1UeContextReleaseCommand(f1apMsg);
+                      break;
+                  }
                default:
                   {
                      DU_LOG("\nERROR  -->  F1AP : Invalid type of F1AP_PDU_PR_initiatingMessage [%d]",