Merge remote-tracking branch 'origin/NGAP-FAILMESSAGE' into integration_2024_w50 (!3163)

NGAP-Initial Context Setup Failure

NGAP Failure message - Initial Context Setup Failure.  When an Initial
Context Setup Request is received with the UE context as null, it
triggers Initial Context Setup failure

openair2/COMMON/ngap_messages_types.h

@@ -553,9 +553,12 @@ typedef struct ngap_initial_context_setup_resp_s {
 } ngap_initial_context_setup_resp_t;
 
 typedef struct ngap_initial_context_setup_fail_s {
-  uint32_t  gNB_ue_ngap_id;
+  uint32_t gNB_ue_ngap_id;
 
-  /* TODO add cause */
+  uint64_t amf_ue_ngap_id;
+
+  ngap_Cause_t cause;
+  long cause_value;
 } ngap_initial_context_setup_fail_t, ngap_ue_ctxt_modification_fail_t, ngap_pdusession_setup_req_fail_t;
 
 typedef struct ngap_nas_non_delivery_ind_s {

openair2/RRC/NR/rrc_gNB_NGAP.c

@@ -432,12 +432,11 @@ int rrc_gNB_process_NGAP_INITIAL_CONTEXT_SETUP_REQ(MessageDef *msg_p, instance_t
 
   if (ue_context_p == NULL) {
     /* Can not associate this message to an UE index, send a failure to NGAP and discard it! */
-    MessageDef *msg_fail_p = NULL;
     LOG_W(NR_RRC, "[gNB %ld] In NGAP_INITIAL_CONTEXT_SETUP_REQ: unknown UE from NGAP ids (%u)\n", instance, req->gNB_ue_ngap_id);
-    msg_fail_p = itti_alloc_new_message(TASK_RRC_GNB, 0, NGAP_INITIAL_CONTEXT_SETUP_FAIL);
+    rrc_gNB_send_NGAP_INITIAL_CONTEXT_SETUP_FAIL(req->gNB_ue_ngap_id,
-    NGAP_INITIAL_CONTEXT_SETUP_FAIL(msg_fail_p).gNB_ue_ngap_id = req->gNB_ue_ngap_id;
+                                                 NULL,
-    // TODO add failure cause when defined!
+                                                 NGAP_CAUSE_RADIO_NETWORK,
-    itti_send_msg_to_task(TASK_NGAP, instance, msg_fail_p);
+                                                 NGAP_CAUSE_RADIO_NETWORK_UNKNOWN_LOCAL_UE_NGAP_ID);
     return (-1);
   }
   gNB_RRC_INST *rrc = RC.nrrrc[instance];
@@ -542,6 +541,20 @@ void rrc_gNB_send_NGAP_INITIAL_CONTEXT_SETUP_RESP(gNB_RRC_INST *rrc, gNB_RRC_UE_
   itti_send_msg_to_task (TASK_NGAP, rrc->module_id, msg_p);
 }
 
+void rrc_gNB_send_NGAP_INITIAL_CONTEXT_SETUP_FAIL(uint32_t gnb,
+                                                  const rrc_gNB_ue_context_t *const ue_context_pP,
+                                                  const ngap_Cause_t causeP,
+                                                  const long cause_valueP)
+{
+  MessageDef *msg_p = itti_alloc_new_message(TASK_RRC_GNB, 0, NGAP_INITIAL_CONTEXT_SETUP_FAIL);
+  ngap_initial_context_setup_fail_t *fail = &NGAP_INITIAL_CONTEXT_SETUP_FAIL(msg_p);
+  memset(fail, 0, sizeof(*fail));
+  fail->gNB_ue_ngap_id = gnb;
+  fail->cause = causeP;
+  fail->cause_value = cause_valueP;
+  itti_send_msg_to_task(TASK_NGAP, 0, msg_p);
+}
+
 static NR_CipheringAlgorithm_t rrc_gNB_select_ciphering(const gNB_RRC_INST *rrc, uint16_t algorithms)
 {
   int i;

openair2/RRC/NR/rrc_gNB_NGAP.h

@@ -46,6 +46,11 @@ int rrc_gNB_process_NGAP_INITIAL_CONTEXT_SETUP_REQ(MessageDef *msg_p, instance_t
 
 void rrc_gNB_send_NGAP_INITIAL_CONTEXT_SETUP_RESP(gNB_RRC_INST *rrc, gNB_RRC_UE_t *UE);
 
+void rrc_gNB_send_NGAP_INITIAL_CONTEXT_SETUP_FAIL(uint32_t gnb,
+                                                  const rrc_gNB_ue_context_t *const ue_context_pP,
+                                                  const ngap_Cause_t causeP,
+                                                  const long cause_valueP);
+
 int rrc_gNB_process_NGAP_DOWNLINK_NAS(MessageDef *msg_p, instance_t instance, mui_t *rrc_gNB_mui);
 
 void rrc_gNB_send_NGAP_UPLINK_NAS(gNB_RRC_INST *rrc, gNB_RRC_UE_t *UE, const NR_UL_DCCH_Message_t *const ul_dcch_msg);

openair3/NGAP/ngap_gNB.c

@@ -328,6 +328,10 @@ void *ngap_gNB_process_itti_msg(void *notUsed) {
         ngap_gNB_initial_ctxt_resp(instance, &NGAP_INITIAL_CONTEXT_SETUP_RESP(received_msg));
         break;
 
+      case NGAP_INITIAL_CONTEXT_SETUP_FAIL:
+        ngap_gNB_initial_ctxt_fail(instance, &NGAP_INITIAL_CONTEXT_SETUP_FAIL(received_msg));
+        break;
+
       case NGAP_PDUSESSION_SETUP_RESP:
         ngap_gNB_pdusession_setup_resp(instance, &NGAP_PDUSESSION_SETUP_RESP(received_msg));
         break;

openair3/NGAP/ngap_gNB_nas_procedures.c

@@ -749,6 +749,115 @@ int ngap_gNB_initial_ctxt_resp(instance_t instance, ngap_initial_context_setup_r
     return 0;
 }
 
+//---------------------------------------------------------------------------------------------------------
+int ngap_gNB_initial_ctxt_fail(instance_t instance, ngap_initial_context_setup_fail_t *initial_ctxt_fail)
+//---------------------------------------------------------------------------------------------------------
+{
+  ngap_gNB_instance_t *ngap_gNB_instance_p = NULL;
+  struct ngap_gNB_ue_context_s *ue_context_p = NULL;
+  NGAP_NGAP_PDU_t pdu;
+  uint8_t *buffer = NULL;
+  uint32_t length;
+
+  /* Retrieve the NGAP gNB instance associated with Mod_id */
+  ngap_gNB_instance_p = ngap_gNB_get_instance(instance);
+  DevAssert(initial_ctxt_fail != NULL);
+  DevAssert(ngap_gNB_instance_p != NULL);
+
+  if ((ue_context_p = ngap_get_ue_context(initial_ctxt_fail->gNB_ue_ngap_id)) == NULL) {
+    /* The context for this gNB ue ngap id doesn't exist in the map of gNB UEs */
+    NGAP_WARN("Failed to find ue context associated with gNB ue ngap id: 0x%08x\n", initial_ctxt_fail->gNB_ue_ngap_id);
+    return -1;
+  }
+  /* Uplink NAS transport can occur either during an ngap connected state
+   * or during initial attach (for example: NAS authentication).
+   */
+  if (!(ue_context_p->ue_state == NGAP_UE_CONNECTED || ue_context_p->ue_state == NGAP_UE_WAITING_CSR)) {
+    NGAP_WARN(
+        "You are attempting to send NAS data over non-connected "
+        "gNB ue ngap id: %08x, current state: %d\n",
+        initial_ctxt_fail->gNB_ue_ngap_id,
+        ue_context_p->ue_state);
+    return -1;
+  }
+
+  /* Prepare the NGAP message to encode */
+  memset(&pdu, 0, sizeof(pdu));
+  pdu.present = NGAP_NGAP_PDU_PR_unsuccessfulOutcome;
+  asn1cCalloc(pdu.choice.unsuccessfulOutcome, out);
+  out->procedureCode = NGAP_ProcedureCode_id_InitialContextSetup;
+  out->criticality = NGAP_Criticality_reject;
+  out->value.present = NGAP_UnsuccessfulOutcome__value_PR_InitialContextSetupFailure;
+  NGAP_InitialContextSetupFailure_t *fail = &out->value.choice.InitialContextSetupFailure;
+  /* mandatory */
+  {
+    asn1cSequenceAdd(fail->protocolIEs.list, NGAP_InitialContextSetupFailureIEs_t, ie);
+    ie->id = NGAP_ProtocolIE_ID_id_AMF_UE_NGAP_ID;
+    ie->criticality = NGAP_Criticality_ignore;
+    ie->value.present = NGAP_InitialContextSetupFailureIEs__value_PR_AMF_UE_NGAP_ID;
+    // ie->value.choice.AMF_UE_NGAP_ID = ue_context_p->amf_ue_ngap_id;
+    asn_uint642INTEGER(&ie->value.choice.AMF_UE_NGAP_ID, ue_context_p->amf_ue_ngap_id);
+  }
+  /* mandatory */
+  {
+    asn1cSequenceAdd(fail->protocolIEs.list, NGAP_InitialContextSetupFailureIEs_t, ie);
+    ie->id = NGAP_ProtocolIE_ID_id_RAN_UE_NGAP_ID;
+    ie->criticality = NGAP_Criticality_ignore;
+    ie->value.present = NGAP_InitialContextSetupFailureIEs__value_PR_RAN_UE_NGAP_ID;
+    ie->value.choice.RAN_UE_NGAP_ID = initial_ctxt_fail->gNB_ue_ngap_id;
+  }
+  /* mandatory */
+  {
+    asn1cSequenceAdd(fail->protocolIEs.list, NGAP_InitialContextSetupFailureIEs_t, ie);
+    ie->id = NGAP_ProtocolIE_ID_id_Cause;
+    ie->criticality = NGAP_Criticality_ignore;
+    ie->value.present = NGAP_InitialContextSetupFailureIEs__value_PR_Cause;
+
+    switch (initial_ctxt_fail->cause) {
+      case NGAP_CAUSE_RADIO_NETWORK:
+        ie->value.choice.Cause.present = NGAP_Cause_PR_radioNetwork;
+        ie->value.choice.Cause.choice.radioNetwork = initial_ctxt_fail->cause_value;
+        break;
+      case NGAP_CAUSE_TRANSPORT:
+        ie->value.choice.Cause.present = NGAP_Cause_PR_transport;
+        ie->value.choice.Cause.choice.transport = initial_ctxt_fail->cause_value;
+        break;
+      case NGAP_CAUSE_NAS:
+        ie->value.choice.Cause.present = NGAP_Cause_PR_nas;
+        ie->value.choice.Cause.choice.nas = initial_ctxt_fail->cause_value;
+        break;
+      case NGAP_CAUSE_PROTOCOL:
+        ie->value.choice.Cause.present = NGAP_Cause_PR_protocol;
+        ie->value.choice.Cause.choice.protocol = initial_ctxt_fail->cause_value;
+        break;
+      case NGAP_CAUSE_MISC:
+        ie->value.choice.Cause.present = NGAP_Cause_PR_misc;
+        ie->value.choice.Cause.choice.misc = initial_ctxt_fail->cause_value;
+        break;
+      case NGAP_CAUSE_NOTHING:
+      default:
+        AssertFatal(false, "Unknown NGAP Initial Context Setup failure cause %d\n", initial_ctxt_fail->cause);
+        break;
+    }
+  }
+  if (asn1_xer_print) {
+    xer_fprint(stdout, &asn_DEF_NGAP_NGAP_PDU, &pdu);
+  }
+  if (ngap_gNB_encode_pdu(&pdu, &buffer, &length) < 0) {
+    NGAP_ERROR("Failed to encode InitialContextSetupFailure\n");
+    /* Encode procedure has failed... */
+    return -1;
+  }
+  /* UE associated signalling -> use the allocated stream */
+  LOG_I(NR_RRC, "Send message to sctp: NGAP_InitialContextSetupFailure\n");
+  ngap_gNB_itti_send_sctp_data_req(ngap_gNB_instance_p->instance,
+                                   ue_context_p->amf_ref->assoc_id,
+                                   buffer,
+                                   length,
+                                   ue_context_p->tx_stream);
+  return 0;
+}
+
 //------------------------------------------------------------------------------
 int ngap_gNB_ue_capabilities(instance_t instance, ngap_ue_cap_info_ind_t *ue_cap_info_ind_p)
 //------------------------------------------------------------------------------

openair3/NGAP/ngap_gNB_nas_procedures.h

@@ -49,6 +49,8 @@ int ngap_gNB_handle_nas_first_req(
 int ngap_gNB_initial_ctxt_resp(
   instance_t instance, ngap_initial_context_setup_resp_t *initial_ctxt_resp_p);
 
+int ngap_gNB_initial_ctxt_fail(instance_t instance, ngap_initial_context_setup_fail_t *initial_ctxt_fail);
+
 int ngap_gNB_ue_capabilities(instance_t instance,
                              ngap_ue_cap_info_ind_t *ue_cap_info_ind_p);