/* * 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 1.0 (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 s1ap_eNB_nnsf.c * \brief s1ap NAS node selection functions * \author Sebastien ROUX <sebastien.roux@eurecom.fr> * \date 2012 * \version 0.1 */ #include <stdio.h> #include <stdlib.h> #include "intertask_interface.h" #include "s1ap_common.h" #include "s1ap_eNB_defs.h" #include "s1ap_eNB_nnsf.h" struct s1ap_eNB_mme_data_s * s1ap_eNB_nnsf_select_mme(s1ap_eNB_instance_t *instance_p, rrc_establishment_cause_t cause) { struct s1ap_eNB_mme_data_s *mme_data_p = NULL; struct s1ap_eNB_mme_data_s *mme_highest_capacity_p = NULL; uint8_t current_capacity = 0; RB_FOREACH(mme_data_p, s1ap_mme_map, &instance_p->s1ap_mme_head) { if (mme_data_p->state != S1AP_ENB_STATE_CONNECTED) { /* The association between MME and eNB is not ready for the moment, * go to the next known MME. */ if (mme_data_p->state == S1AP_ENB_OVERLOAD) { /* MME is overloaded. We have to check the RRC establishment * cause and take decision to the select this MME depending on * the overload state. */ if ((cause == RRC_CAUSE_MO_DATA) && (mme_data_p->overload_state == S1AP_OVERLOAD_REJECT_MO_DATA)) { continue; } if ((mme_data_p->overload_state == S1AP_OVERLOAD_REJECT_ALL_SIGNALLING) && ((cause == RRC_CAUSE_MO_SIGNALLING) || (cause == RRC_CAUSE_MO_DATA))) { continue; } if ((mme_data_p->overload_state == S1AP_OVERLOAD_ONLY_EMERGENCY_AND_MT) && ((cause == RRC_CAUSE_MO_SIGNALLING) || (cause == RRC_CAUSE_MO_DATA) || (cause == RRC_CAUSE_HIGH_PRIO_ACCESS))) { continue; } /* At this point, the RRC establishment can be handled by the MME * even if it is in overload state. */ } else { /* The MME is not overloaded, association is simply not ready. */ continue; } } if (current_capacity < mme_data_p->relative_mme_capacity) { /* We find a better MME, keep a reference to it */ current_capacity = mme_data_p->relative_mme_capacity; mme_highest_capacity_p = mme_data_p; } } return mme_highest_capacity_p; } struct s1ap_eNB_mme_data_s * s1ap_eNB_nnsf_select_mme_by_mme_code(s1ap_eNB_instance_t *instance_p, rrc_establishment_cause_t cause, uint8_t mme_code) { struct s1ap_eNB_mme_data_s *mme_data_p = NULL; struct s1ap_eNB_mme_data_s *mme_highest_capacity_p = NULL; uint8_t current_capacity = 0; RB_FOREACH(mme_data_p, s1ap_mme_map, &instance_p->s1ap_mme_head) { struct served_gummei_s *gummei_p = NULL; if (mme_data_p->state != S1AP_ENB_STATE_CONNECTED) { /* The association between MME and eNB is not ready for the moment, * go to the next known MME. */ if (mme_data_p->state == S1AP_ENB_OVERLOAD) { /* MME is overloaded. We have to check the RRC establishment * cause and take decision to the select this MME depending on * the overload state. */ if ((cause == RRC_CAUSE_MO_DATA) && (mme_data_p->overload_state == S1AP_OVERLOAD_REJECT_MO_DATA)) { continue; } if ((mme_data_p->overload_state == S1AP_OVERLOAD_REJECT_ALL_SIGNALLING) && ((cause == RRC_CAUSE_MO_SIGNALLING) || (cause == RRC_CAUSE_MO_DATA))) { continue; } if ((mme_data_p->overload_state == S1AP_OVERLOAD_ONLY_EMERGENCY_AND_MT) && ((cause == RRC_CAUSE_MO_SIGNALLING) || (cause == RRC_CAUSE_MO_DATA) || (cause == RRC_CAUSE_HIGH_PRIO_ACCESS))) { continue; } /* At this point, the RRC establishment can be handled by the MME * even if it is in overload state. */ } else { /* The MME is not overloaded, association is simply not ready. */ continue; } } if (current_capacity < mme_data_p->relative_mme_capacity) { /* We find a better MME, keep a reference to it */ current_capacity = mme_data_p->relative_mme_capacity; mme_highest_capacity_p = mme_data_p; } /* Looking for MME code matching the one provided by NAS */ STAILQ_FOREACH(gummei_p, &mme_data_p->served_gummei, next) { struct mme_code_s *mme_code_p = NULL; STAILQ_FOREACH(mme_code_p, &gummei_p->mme_codes, next) { if (mme_code_p->mme_code == mme_code) { return mme_data_p; } } } } /* At this point no MME matches the provided GUMMEI. Select the one with the * highest relative capacity. * In case the list of known MME is empty, simply return NULL, that way the RRC * layer should know about it and reject RRC connectivity. */ return mme_highest_capacity_p; } struct s1ap_eNB_mme_data_s * s1ap_eNB_nnsf_select_mme_by_gummei(s1ap_eNB_instance_t *instance_p, rrc_establishment_cause_t cause, s1ap_gummei_t gummei) { struct s1ap_eNB_mme_data_s *mme_data_p = NULL; struct s1ap_eNB_mme_data_s *mme_highest_capacity_p = NULL; uint8_t current_capacity = 0; RB_FOREACH(mme_data_p, s1ap_mme_map, &instance_p->s1ap_mme_head) { struct served_gummei_s *gummei_p = NULL; if (mme_data_p->state != S1AP_ENB_STATE_CONNECTED) { /* The association between MME and eNB is not ready for the moment, * go to the next known MME. */ if (mme_data_p->state == S1AP_ENB_OVERLOAD) { /* MME is overloaded. We have to check the RRC establishment * cause and take decision to the select this MME depending on * the overload state. */ if ((cause == RRC_CAUSE_MO_DATA) && (mme_data_p->overload_state == S1AP_OVERLOAD_REJECT_MO_DATA)) { continue; } if ((mme_data_p->overload_state == S1AP_OVERLOAD_REJECT_ALL_SIGNALLING) && ((cause == RRC_CAUSE_MO_SIGNALLING) || (cause == RRC_CAUSE_MO_DATA))) { continue; } if ((mme_data_p->overload_state == S1AP_OVERLOAD_ONLY_EMERGENCY_AND_MT) && ((cause == RRC_CAUSE_MO_SIGNALLING) || (cause == RRC_CAUSE_MO_DATA) || (cause == RRC_CAUSE_HIGH_PRIO_ACCESS))) { continue; } /* At this point, the RRC establishment can be handled by the MME * even if it is in overload state. */ } else { /* The MME is not overloaded, association is simply not ready. */ continue; } } if (current_capacity < mme_data_p->relative_mme_capacity) { /* We find a better MME, keep a reference to it */ current_capacity = mme_data_p->relative_mme_capacity; mme_highest_capacity_p = mme_data_p; } /* Looking for MME gummei matching the one provided by NAS */ STAILQ_FOREACH(gummei_p, &mme_data_p->served_gummei, next) { struct served_group_id_s *group_id_p = NULL; struct mme_code_s *mme_code_p = NULL; struct plmn_identity_s *served_plmn_p = NULL; STAILQ_FOREACH(served_plmn_p, &gummei_p->served_plmns, next) { if ((served_plmn_p->mcc == gummei.mcc) && (served_plmn_p->mnc == gummei.mnc)) { break; } } STAILQ_FOREACH(mme_code_p, &gummei_p->mme_codes, next) { if (mme_code_p->mme_code == gummei.mme_code) { break; } } STAILQ_FOREACH(group_id_p, &gummei_p->served_group_ids, next) { if (group_id_p->mme_group_id == gummei.mme_group_id) { break; } } /* The MME matches the parameters provided by the NAS layer -> * the MME is knwown and the association is ready. * Return the reference to the MME to use it for this UE. */ if ((group_id_p != NULL) && (mme_code_p != NULL) && (served_plmn_p != NULL)) { return mme_data_p; } } } /* At this point no MME matches the provided GUMMEI. Select the one with the * highest relative capacity. * In case the list of known MME is empty, simply return NULL, that way the RRC * layer should know about it and reject RRC connectivity. */ return mme_highest_capacity_p; }