Add handling of F1 Ue context setup request message at the DU side

- Trigger SRB2 and DRB configuration and RRC->MAC configuration
- Remaining: gtp-u tunnel creation at the DU side, triggering and handling of UE context setup response

openair2/COMMON/f1ap_messages_types.h

@@ -326,6 +326,11 @@ typedef struct f1ap_drb_to_be_setup_s {
   rlc_mode_t     rlc_mode;
 } f1ap_drb_to_be_setup_t;
 
+typedef struct f1ap_srb_to_be_setup_s {
+  long           srb_id;
+  rlc_mode_t     rlc_mode;
+} f1ap_srb_to_be_setup_t;
+
 typedef struct f1ap_ue_context_setup_req_s {
   uint32_t gNB_CU_ue_id;    // BK: need to replace by use from rnti
   uint32_t *gNB_DU_ue_id;
@@ -342,6 +347,8 @@ typedef struct f1ap_ue_context_setup_req_s {
   uint8_t  cu_to_du_rrc_information_length;
   f1ap_drb_to_be_setup_t *drbs_to_be_setup; // BK: need to replace by s1ap_initial_context_setup_req
   uint8_t  drbs_to_be_setup_length;       // BK: need to replace by s1ap_initial_context_setup_req
+  f1ap_srb_to_be_setup_t *srbs_to_be_setup;
+  uint8_t  srbs_to_be_setup_length;
   s1ap_initial_context_setup_req_t *s1ap_initial_context_setup_req;
    // coniatner for the rrc_eNB_generate_SecurityModeCommand message
   uint8_t *rrc_container;

openair2/COMMON/rrc_messages_def.h

@@ -80,4 +80,4 @@ MESSAGE_DEF(RRC_SUBFRAME_PROCESS,       MESSAGE_PRIORITY_MED,       RrcSubframeP
 // eNB: RLC -> RRC messages
 MESSAGE_DEF(RLC_SDU_INDICATION,         MESSAGE_PRIORITY_MED,       RlcSduIndication,           rlc_sdu_indication)
 
-MESSAGE_DEF(NR_DU_RRC_DL_INDICATION, MESSAGE_PRIORITY_MED, NRDuDlReq_t, nr_du_dl_req)
+MESSAGE_DEF(NR_DU_RRC_DL_INDICATION,    MESSAGE_PRIORITY_MED,       NRDuDlReq_t,                nr_du_dl_req)

openair2/F1AP/f1ap_cu_ue_context_management.c

@@ -87,7 +87,7 @@ int CU_send_UE_CONTEXT_SETUP_REQUEST(instance_t instance,
   ie1->id                             = F1AP_ProtocolIE_ID_id_gNB_CU_UE_F1AP_ID;
   ie1->criticality                    = F1AP_Criticality_reject;
   ie1->value.present                  = F1AP_UEContextSetupRequestIEs__value_PR_GNB_CU_UE_F1AP_ID;
-  ie1->value.choice.GNB_CU_UE_F1AP_ID = f1ap_ue_context_setup_req->gNB_CU_ue_id;
+  ie1->value.choice.GNB_CU_UE_F1AP_ID = f1ap_get_cu_ue_f1ap_id(true, instance, f1ap_ue_context_setup_req->rnti); //f1ap_ue_context_setup_req->gNB_CU_ue_id;
 
   /* optional */
   /* c2. GNB_DU_UE_F1AP_ID */
@@ -96,7 +96,7 @@ int CU_send_UE_CONTEXT_SETUP_REQUEST(instance_t instance,
     ie2->id                             = F1AP_ProtocolIE_ID_id_gNB_DU_UE_F1AP_ID;
     ie2->criticality                    = F1AP_Criticality_ignore;
     ie2->value.present                  = F1AP_UEContextSetupRequestIEs__value_PR_GNB_DU_UE_F1AP_ID;
-    ie2->value.choice.GNB_DU_UE_F1AP_ID = *f1ap_ue_context_setup_req->gNB_DU_ue_id;
+    ie2->value.choice.GNB_DU_UE_F1AP_ID = f1ap_get_du_ue_f1ap_id(true, instance, f1ap_ue_context_setup_req->rnti); //*f1ap_ue_context_setup_req->gNB_DU_ue_id;
   }
 
   /* mandatory */

openair2/F1AP/f1ap_du_ue_context_management.c

@@ -100,6 +100,8 @@ int DU_handle_UE_CONTEXT_SETUP_REQUEST(instance_t       instance,
     f1ap_ue_context_setup_req->cellULConfigured = NULL;
   }
 
+  f1ap_drb_to_be_setup_t *drb_p;
+  f1ap_srb_to_be_setup_t *srb_p;
   if (RC.nrrrc) {
     /* RRCContainer */
     F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextSetupRequestIEs_t, ie, container,
@@ -111,7 +113,7 @@ int DU_handle_UE_CONTEXT_SETUP_REQUEST(instance_t       instance,
                 "could not allocate memory for f1ap_ue_context_setup_req->drbs_to_be_setup\n");
 
     for (i = 0; i < f1ap_ue_context_setup_req->drbs_to_be_setup_length; ++i) {
-      f1ap_drb_to_be_setup_t *drb_p = &f1ap_ue_context_setup_req->drbs_to_be_setup[i];
+      drb_p = &f1ap_ue_context_setup_req->drbs_to_be_setup[i];
       F1AP_DRBs_ToBeSetup_Item_t *drbs_tobesetup_item_p;
       drbs_tobesetup_item_p = &((F1AP_DRBs_ToBeSetup_ItemIEs_t *)ie->value.choice.DRBs_ToBeSetup_List.list.array[i])->value.choice.DRBs_ToBeSetup_Item;
       drb_p->drb_id = drbs_tobesetup_item_p->dRBID;
@@ -135,12 +137,40 @@ int DU_handle_UE_CONTEXT_SETUP_REQUEST(instance_t       instance,
           break;
       }
     }
+    F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextSetupRequestIEs_t, ie, container,
+                                   F1AP_ProtocolIE_ID_id_SRBs_ToBeSetup_List, true);
+    f1ap_ue_context_setup_req->srbs_to_be_setup_length = ie->value.choice.SRBs_ToBeSetup_List.list.count;
+    f1ap_ue_context_setup_req->srbs_to_be_setup = calloc(f1ap_ue_context_setup_req->srbs_to_be_setup_length,
+            sizeof(f1ap_srb_to_be_setup_t));
+    AssertFatal(f1ap_ue_context_setup_req->srbs_to_be_setup,
+                    "could not allocate memory for f1ap_ue_context_setup_req->srbs_to_be_setup\n");
+
+    for (i = 0; i < f1ap_ue_context_setup_req->srbs_to_be_setup_length; ++i) {
+      srb_p = &f1ap_ue_context_setup_req->srbs_to_be_setup[i];
+      F1AP_SRBs_ToBeSetup_Item_t *srbs_tobesetup_item_p;
+            srbs_tobesetup_item_p = &((F1AP_SRBs_ToBeSetup_ItemIEs_t *)ie->value.choice.SRBs_ToBeSetup_List.list.array[i])->value.choice.SRBs_ToBeSetup_Item;
+            srb_p->srb_id = srbs_tobesetup_item_p->sRBID;
+    }
   }
 
   /* RRCContainer */
   F1AP_FIND_PROTOCOLIE_BY_ID(F1AP_UEContextSetupRequestIEs_t, ie, container,
                              F1AP_ProtocolIE_ID_id_RRCContainer, false);
 
+  if(f1ap_ue_context_setup_req->gNB_DU_ue_id!=NULL){
+    f1ap_ue_context_setup_req->rnti = f1ap_get_rnti_by_du_id(false, instance, *f1ap_ue_context_setup_req->gNB_DU_ue_id);
+  }
+  else{
+    f1ap_ue_context_setup_req->rnti = f1ap_get_rnti_by_cu_id(false, instance, f1ap_ue_context_setup_req->gNB_CU_ue_id);
+  }
+
+  if(f1ap_ue_context_setup_req->rnti<0){
+    LOG_E(F1AP, "Could not retrieve UE rnti based on the CU/DU UE id \n");
+  }
+  else{
+    LOG_I(F1AP, "Retrieved rnti is: %d \n", f1ap_ue_context_setup_req->rnti);
+  }
+
   if (ie) {
     /* correct here */
     f1ap_ue_context_setup_req->rrc_container = malloc(ie->value.choice.RRCContainer.size);
@@ -170,7 +200,10 @@ int DU_handle_UE_CONTEXT_SETUP_REQUEST(instance_t       instance,
   } else {
     LOG_E(F1AP, "can't find RRCContainer in UEContextSetupRequestIEs by id %ld \n", F1AP_ProtocolIE_ID_id_RRCContainer);
   }
-    return 0;
+
+  itti_send_msg_to_task(TASK_RRC_GNB, instance, msg_p);
+
+  return 0;
 }
 
 //void DU_send_UE_CONTEXT_SETUP_RESPONSE(F1AP_UEContextSetupResponse_t *UEContextSetupResponse) {

openair2/LAYER2/nr_rlc/nr_rlc_oai_api.c

@@ -506,6 +506,10 @@ rb_found:
       itti_send_msg_to_task(TASK_DU_F1, ENB_MODULE_ID_TO_INSTANCE(0 /*ctxt_pP->module_id*/), msg);
       return;
     }
+    else if(NODE_IS_DU(type) && is_srb == 0) {
+      LOG_W(RLC, "Received uplink user-plane traffic at RLC-DU to be sent to the CU, but F1-U implementation is not in place yet \n");
+      return;
+    }
   }
 
   if (!pdcp_data_ind(&ctx, is_srb, 0, rb_id, size, memblock)) {
@@ -715,7 +719,7 @@ static void add_rlc_srb(int rnti, struct NR_SRB_ToAddMod *s, NR_RLC_BearerConfig
                                      sn_field_length);
     nr_rlc_ue_add_srb_rlc_entity(ue, srb_id, nr_rlc_am);
 
-    LOG_D(RLC, "%s:%d:%s: added srb %d to UE with RNTI 0x%x\n", __FILE__, __LINE__, __FUNCTION__, srb_id, rnti);
+    LOG_I(RLC, "%s:%d:%s: added srb %d to UE with RNTI 0x%x\n", __FILE__, __LINE__, __FUNCTION__, srb_id, rnti);
   }
   nr_rlc_manager_unlock(nr_rlc_ue_manager);
 }
@@ -797,7 +801,7 @@ static void add_drb_am(int rnti, struct NR_DRB_ToAddMod *s, NR_RLC_BearerConfig_
                                      sn_field_length);
     nr_rlc_ue_add_drb_rlc_entity(ue, drb_id, nr_rlc_am);
 
-    LOG_D(RLC, "%s:%d:%s: added drb %d to UE with RNTI 0x%x\n", __FILE__, __LINE__, __FUNCTION__, drb_id, rnti);
+    LOG_I(RLC, "%s:%d:%s: added drb %d to UE with RNTI 0x%x\n", __FILE__, __LINE__, __FUNCTION__, drb_id, rnti);
   }
   nr_rlc_manager_unlock(nr_rlc_ue_manager);
 }

openair2/RRC/NR/rrc_gNB.c

@@ -400,7 +400,7 @@ void apply_macrlc_config(gNB_RRC_INST *rrc,
 
       nr_rrc_rlc_config_asn1_req(ctxt_pP,
                                  ue_context_pP->ue_context.SRB_configList,
-                                 NULL,
+                                 ue_context_pP->ue_context.DRB_configList,
                                  NULL,
                                  NULL,
                                  get_softmodem_params()->sa ? ue_context_pP->ue_context.masterCellGroup->rlc_BearerToAddModList : NULL);
@@ -3107,6 +3107,52 @@ static int  rrc_process_DU_DL(MessageDef *msg_p, const char *msg_name, instance_
 return 0;
 }
 
+static void rrc_DU_process_ue_context_setup_request(MessageDef *msg_p, const char *msg_name, instance_t instance){
+
+  f1ap_ue_context_setup_req_t * req=&F1AP_UE_CONTEXT_SETUP_REQ(msg_p);
+  protocol_ctxt_t ctxt;
+  ctxt.rnti      = req->rnti;
+  ctxt.module_id = instance;
+  ctxt.instance  = instance;
+  ctxt.enb_flag  = 1;
+  gNB_RRC_INST *rrc = RC.nrrrc[ctxt.module_id];
+  struct rrc_gNB_ue_context_s *ue_context_p =
+      rrc_gNB_get_ue_context(rrc, ctxt.rnti);
+
+
+  NR_CellGroupConfig_t *cellGroupConfig;
+  cellGroupConfig = calloc(1, sizeof(NR_CellGroupConfig_t));
+  fill_mastercellGroupConfig(cellGroupConfig, ue_context_p->ue_context.masterCellGroup);
+
+  /* Configure SRB2 */
+  NR_SRB_ToAddMod_t            *SRB2_config          = NULL;
+  NR_SRB_ToAddModList_t        *SRB_configList  = ue_context_p->ue_context.SRB_configList;
+  if(SRB_configList != NULL){
+    for (int i=0; i<req->srbs_to_be_setup_length; i++){
+      SRB2_config = CALLOC(1, sizeof(*SRB2_config));
+      SRB2_config->srb_Identity = req->srbs_to_be_setup[i].srb_id;
+      ASN_SEQUENCE_ADD(&SRB_configList->list, SRB2_config);
+    }
+  }
+  else{
+    LOG_E(NR_RRC, "The SRB list of the UE context is empty before the addition of SRB2 \n");
+    return;
+  }
+  /* Configure DRB */
+  NR_DRB_ToAddMod_t            *DRB_config          = NULL;
+  if(ue_context_p->ue_context.DRB_configList == NULL){
+    ue_context_p->ue_context.DRB_configList = CALLOC(1, sizeof(*ue_context_p->ue_context.DRB_configList));
+  }
+  NR_DRB_ToAddModList_t        *DRB_configList  = ue_context_p->ue_context.DRB_configList;
+
+  for (int i=0; i<req->drbs_to_be_setup_length; i++){
+    DRB_config = CALLOC(1, sizeof(*DRB_config));
+    DRB_config->drb_Identity = req->drbs_to_be_setup[i].drb_id;
+    ASN_SEQUENCE_ADD(&DRB_configList->list, DRB_config);
+  }
+  apply_macrlc_config(rrc, ue_context_p, &ctxt);
+}
+
 unsigned int mask_flip(unsigned int x) {
   return((((x>>8) + (x<<8))&0xffff)>>6);
 }
@@ -3602,6 +3648,10 @@ void *rrc_gnb_task(void *args_p) {
       rrc_process_DU_DL(msg_p, msg_name_p, instance);
       break;
       
+    case F1AP_UE_CONTEXT_SETUP_REQ:
+      rrc_DU_process_ue_context_setup_request(msg_p, msg_name_p, instance);
+      break;
+
       /* Messages from X2AP */
       case X2AP_ENDC_SGNB_ADDITION_REQ:
         LOG_I(NR_RRC, "Received ENDC sgNB addition request from X2AP \n");