/* * 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 ngap_gNB_nnsf.c * \brief ngap NAS node selection functions * \author Yoshio INOUE, Masayuki HARADA * \date 2020 * \version 0.1 * \email: yoshio.inoue@fujitsu.com,masayuki.harada@fujitsu.com (yoshio.inoue%40fujitsu.com%2cmasayuki.harada%40fujitsu.com) */ #include <stdio.h> #include <stdlib.h> #include "intertask_interface.h" #include "ngap_common.h" #include "ngap_gNB_defs.h" #include "ngap_gNB_nnsf.h" struct ngap_gNB_amf_data_s * ngap_gNB_nnsf_select_amf(ngap_gNB_instance_t *instance_p, ngap_rrc_establishment_cause_t cause) { struct ngap_gNB_amf_data_s *amf_data_p = NULL; struct ngap_gNB_amf_data_s *amf_highest_capacity_p = NULL; uint8_t current_capacity = 0; RB_FOREACH(amf_data_p, ngap_amf_map, &instance_p->ngap_amf_head) { if (amf_data_p->state != NGAP_GNB_STATE_CONNECTED) { /* The association between AMF and gNB is not ready for the moment, * go to the next known AMF. */ if (amf_data_p->state == NGAP_GNB_OVERLOAD) { /* AMF is overloaded. We have to check the RRC establishment * cause and take decision to the select this AMF depending on * the overload state. */ if ((cause == NGAP_RRC_CAUSE_MO_DATA) && (amf_data_p->overload_state == NGAP_OVERLOAD_REJECT_MO_DATA)) { continue; } if ((amf_data_p->overload_state == NGAP_OVERLOAD_REJECT_ALL_SIGNALLING) && ((cause == NGAP_RRC_CAUSE_MO_SIGNALLING) || (cause == NGAP_RRC_CAUSE_MO_DATA))) { continue; } if ((amf_data_p->overload_state == NGAP_OVERLOAD_ONLY_EMERGENCY_AND_MT) && ((cause == NGAP_RRC_CAUSE_MO_SIGNALLING) || (cause == NGAP_RRC_CAUSE_MO_DATA) || (cause == NGAP_RRC_CAUSE_HIGH_PRIO_ACCESS))) { continue; } /* At this point, the RRC establishment can be handled by the AMF * even if it is in overload state. */ } else { /* The AMF is not overloaded, association is simply not ready. */ continue; } } if (current_capacity < amf_data_p->relative_amf_capacity) { /* We find a better AMF, keep a reference to it */ current_capacity = amf_data_p->relative_amf_capacity; amf_highest_capacity_p = amf_data_p; } } return amf_highest_capacity_p; } struct ngap_gNB_amf_data_s * ngap_gNB_nnsf_select_amf_by_plmn_id(ngap_gNB_instance_t *instance_p, ngap_rrc_establishment_cause_t cause, int selected_plmn_identity) { struct ngap_gNB_amf_data_s *amf_data_p = NULL; struct ngap_gNB_amf_data_s *amf_highest_capacity_p = NULL; uint8_t current_capacity = 0; RB_FOREACH(amf_data_p, ngap_amf_map, &instance_p->ngap_amf_head) { struct served_guami_s *guami_p = NULL; struct plmn_identity_s *served_plmn_p = NULL; if (amf_data_p->state != NGAP_GNB_STATE_CONNECTED) { /* The association between AMF and gNB is not ready for the moment, * go to the next known AMF. */ if (amf_data_p->state == NGAP_GNB_OVERLOAD) { /* AMF is overloaded. We have to check the RRC establishment * cause and take decision to the select this AMF depending on * the overload state. */ if ((cause == NGAP_RRC_CAUSE_MO_DATA) && (amf_data_p->overload_state == NGAP_OVERLOAD_REJECT_MO_DATA)) { continue; } if ((amf_data_p->overload_state == NGAP_OVERLOAD_REJECT_ALL_SIGNALLING) && ((cause == NGAP_RRC_CAUSE_MO_SIGNALLING) || (cause == NGAP_RRC_CAUSE_MO_DATA))) { continue; } if ((amf_data_p->overload_state == NGAP_OVERLOAD_ONLY_EMERGENCY_AND_MT) && ((cause == NGAP_RRC_CAUSE_MO_SIGNALLING) || (cause == NGAP_RRC_CAUSE_MO_DATA) || (cause == NGAP_RRC_CAUSE_HIGH_PRIO_ACCESS))) { continue; } /* At this point, the RRC establishment can be handled by the AMF * even if it is in overload state. */ } else { /* The AMF is not overloaded, association is simply not ready. */ continue; } } /* Looking for served GUAMI PLMN Identity selected matching the one provided by the UE */ STAILQ_FOREACH(guami_p, &amf_data_p->served_guami, next) { STAILQ_FOREACH(served_plmn_p, &guami_p->served_plmns, next) { if ((served_plmn_p->mcc == instance_p->mcc[selected_plmn_identity]) && (served_plmn_p->mnc == instance_p->mnc[selected_plmn_identity])) { break; } } /* if found, we can stop the outer loop, too */ if (served_plmn_p) break; } /* if we didn't find such a served PLMN, go on with the next AMF */ if (!served_plmn_p) continue; if (current_capacity < amf_data_p->relative_amf_capacity) { /* We find a better AMF, keep a reference to it */ current_capacity = amf_data_p->relative_amf_capacity; amf_highest_capacity_p = amf_data_p; } } return amf_highest_capacity_p; } struct ngap_gNB_amf_data_s * ngap_gNB_nnsf_select_amf_by_amf_setid(ngap_gNB_instance_t *instance_p, ngap_rrc_establishment_cause_t cause, int selected_plmn_identity, uint8_t amf_setid) { struct ngap_gNB_amf_data_s *amf_data_p = NULL; RB_FOREACH(amf_data_p, ngap_amf_map, &instance_p->ngap_amf_head) { struct served_guami_s *guami_p = NULL; if (amf_data_p->state != NGAP_GNB_STATE_CONNECTED) { /* The association between AMF and gNB is not ready for the moment, * go to the next known AMF. */ if (amf_data_p->state == NGAP_GNB_OVERLOAD) { /* AMF is overloaded. We have to check the RRC establishment * cause and take decision to the select this AMF depending on * the overload state. */ if ((cause == NGAP_RRC_CAUSE_MO_DATA) && (amf_data_p->overload_state == NGAP_OVERLOAD_REJECT_MO_DATA)) { continue; } if ((amf_data_p->overload_state == NGAP_OVERLOAD_REJECT_ALL_SIGNALLING) && ((cause == NGAP_RRC_CAUSE_MO_SIGNALLING) || (cause == NGAP_RRC_CAUSE_MO_DATA))) { continue; } if ((amf_data_p->overload_state == NGAP_OVERLOAD_ONLY_EMERGENCY_AND_MT) && ((cause == NGAP_RRC_CAUSE_MO_SIGNALLING) || (cause == NGAP_RRC_CAUSE_MO_DATA) || (cause == NGAP_RRC_CAUSE_HIGH_PRIO_ACCESS))) { continue; } /* At this point, the RRC establishment can be handled by the AMF * even if it is in overload state. */ } else { /* The AMF is not overloaded, association is simply not ready. */ continue; } } /* Looking for AMF code matching the one provided by NAS */ STAILQ_FOREACH(guami_p, &amf_data_p->served_guami, next) { struct amf_set_id_s *amf_setid_p = NULL; struct plmn_identity_s *served_plmn_p = NULL; STAILQ_FOREACH(served_plmn_p, &guami_p->served_plmns, next) { if ((served_plmn_p->mcc == instance_p->mcc[selected_plmn_identity]) && (served_plmn_p->mnc == instance_p->mnc[selected_plmn_identity])) { break; } } STAILQ_FOREACH(amf_setid_p, &guami_p->amf_set_ids, next) { if (amf_setid_p->amf_set_id == amf_setid) { break; } } /* The AMF matches the parameters provided by the NAS layer -> * the AMF is knwown and the association is ready. * Return the reference to the AMF to use it for this UE. */ if (amf_setid_p && served_plmn_p) { return amf_data_p; } } } /* At this point no AMF matches the selected PLMN and AMF code. In this case, * return NULL. That way the RRC layer should know about it and reject RRC * connectivity. */ return NULL; } struct ngap_gNB_amf_data_s * ngap_gNB_nnsf_select_amf_by_guami(ngap_gNB_instance_t *instance_p, ngap_rrc_establishment_cause_t cause, ngap_guami_t guami) { struct ngap_gNB_amf_data_s *amf_data_p = NULL; RB_FOREACH(amf_data_p, ngap_amf_map, &instance_p->ngap_amf_head) { struct served_guami_s *guami_p = NULL; if (amf_data_p->state != NGAP_GNB_STATE_CONNECTED) { /* The association between AMF and gNB is not ready for the moment, * go to the next known AMF. */ if (amf_data_p->state == NGAP_GNB_OVERLOAD) { /* AMF is overloaded. We have to check the RRC establishment * cause and take decision to the select this AMF depending on * the overload state. */ if ((cause == NGAP_RRC_CAUSE_MO_DATA) && (amf_data_p->overload_state == NGAP_OVERLOAD_REJECT_MO_DATA)) { continue; } if ((amf_data_p->overload_state == NGAP_OVERLOAD_REJECT_ALL_SIGNALLING) && ((cause == NGAP_RRC_CAUSE_MO_SIGNALLING) || (cause == NGAP_RRC_CAUSE_MO_DATA))) { continue; } if ((amf_data_p->overload_state == NGAP_OVERLOAD_ONLY_EMERGENCY_AND_MT) && ((cause == NGAP_RRC_CAUSE_MO_SIGNALLING) || (cause == NGAP_RRC_CAUSE_MO_DATA) || (cause == NGAP_RRC_CAUSE_HIGH_PRIO_ACCESS))) { continue; } /* At this point, the RRC establishment can be handled by the AMF * even if it is in overload state. */ } else { /* The AMF is not overloaded, association is simply not ready. */ continue; } } /* Looking for AMF guami matching the one provided by NAS */ STAILQ_FOREACH(guami_p, &amf_data_p->served_guami, next) { struct served_region_id_s *region_id_p = NULL; struct amf_set_id_s *amf_set_id_p = NULL; struct amf_pointer_s *pointer_p = NULL; struct plmn_identity_s *served_plmn_p = NULL; STAILQ_FOREACH(served_plmn_p, &guami_p->served_plmns, next) { if ((served_plmn_p->mcc == guami.mcc) && (served_plmn_p->mnc == guami.mnc)) { break; } } STAILQ_FOREACH(region_id_p, &guami_p->served_region_ids, next) { if (region_id_p->amf_region_id == guami.amf_region_id) { break; } } STAILQ_FOREACH(amf_set_id_p, &guami_p->amf_set_ids, next) { if (amf_set_id_p->amf_set_id == guami.amf_set_id) { break; } } STAILQ_FOREACH(pointer_p, &guami_p->amf_pointers, next) { if (pointer_p->amf_pointer == guami.amf_pointer) { break; } } /* The AMF matches the parameters provided by the NAS layer -> * the AMF is knwown and the association is ready. * Return the reference to the AMF to use it for this UE. */ if ((region_id_p != NULL) && (amf_set_id_p != NULL) && (pointer_p != NULL) && (served_plmn_p != NULL)) { return amf_data_p; } } } /* At this point no AMF matches the provided GUAMI. In this case, return * NULL. That way the RRC layer should know about it and reject RRC * connectivity. */ return NULL; } struct ngap_gNB_amf_data_s * ngap_gNB_nnsf_select_amf_by_guami_no_cause(ngap_gNB_instance_t *instance_p, ngap_guami_t guami) { struct ngap_gNB_amf_data_s *amf_data_p = NULL; struct ngap_gNB_amf_data_s *amf_highest_capacity_p = NULL; uint8_t current_capacity = 0; RB_FOREACH(amf_data_p, ngap_amf_map, &instance_p->ngap_amf_head) { struct served_guami_s *guami_p = NULL; if (amf_data_p->state != NGAP_GNB_STATE_CONNECTED) { /* The association between AMF and gNB is not ready for the moment, * go to the next known AMF. */ if (amf_data_p->state == NGAP_GNB_OVERLOAD) { /* AMF is overloaded. We have to check the RRC establishment * cause and take decision to the select this AMF depending on * the overload state. */ } else { /* The AMF is not overloaded, association is simply not ready. */ continue; } } if (current_capacity < amf_data_p->relative_amf_capacity) { /* We find a better AMF, keep a reference to it */ current_capacity = amf_data_p->relative_amf_capacity; amf_highest_capacity_p = amf_data_p; } /* Looking for AMF guami matching the one provided by NAS */ STAILQ_FOREACH(guami_p, &amf_data_p->served_guami, next) { struct served_region_id_s *region_id_p = NULL; struct amf_set_id_s *amf_set_id_p = NULL; struct plmn_identity_s *served_plmn_p = NULL; STAILQ_FOREACH(served_plmn_p, &guami_p->served_plmns, next) { if ((served_plmn_p->mcc == guami.mcc) && (served_plmn_p->mnc == guami.mnc)) { break; } } STAILQ_FOREACH(amf_set_id_p, &guami_p->amf_set_ids, next) { if (amf_set_id_p->amf_set_id == guami.amf_set_id) { break; } } STAILQ_FOREACH(region_id_p, &guami_p->served_region_ids, next) { if (region_id_p->amf_region_id == guami.amf_region_id) { break; } } /* The AMF matches the parameters provided by the NAS layer -> * the AMF is knwown and the association is ready. * Return the reference to the AMF to use it for this UE. */ if ((region_id_p != NULL) && (amf_set_id_p != NULL) && (served_plmn_p != NULL)) { return amf_data_p; } } } /* At this point no AMF matches the provided GUAMI. Select the one with the * highest relative capacity. * In case the list of known AMF is empty, simply return NULL, that way the RRC * layer should know about it and reject RRC connectivity. */ return amf_highest_capacity_p; }