/* * Copyright 2013-2019 Software Radio Systems Limited * * This file is part of srsLTE. * * srsLTE is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as * published by the Free Software Foundation, either version 3 of * the License, or (at your option) any later version. * * srsLTE is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * A copy of the GNU Affero General Public License can be found in * the LICENSE file in the top-level directory of this distribution * and at http://www.gnu.org/licenses/. * */ #ifndef SRSENB_S1AP_H #define SRSENB_S1AP_H #include #include "common_enb.h" #include "srslte/common/buffer_pool.h" #include "srslte/common/common.h" #include "srslte/common/log.h" #include "srslte/common/threads.h" #include "srslte/interfaces/enb_interfaces.h" #include "s1ap_metrics.h" #include "srslte/asn1/liblte_s1ap.h" #include "srslte/common/network_utils.h" #include "srslte/common/stack_procedure.h" namespace srsenb { typedef struct { uint32_t rnti; uint32_t eNB_UE_S1AP_ID; uint32_t MME_UE_S1AP_ID; bool release_requested; uint16_t stream_id; struct timeval init_timestamp; } ue_ctxt_t; class s1ap : public s1ap_interface_rrc { public: s1ap(); bool init(s1ap_args_t args_, rrc_interface_s1ap* rrc_, srslte::log* s1ap_log_, srslte::timer_handler* timers_, srsenb::stack_interface_s1ap_lte* stack_); void stop(); void get_metrics(s1ap_metrics_t& m); // RRC interface void initial_ue(uint16_t rnti, LIBLTE_S1AP_RRC_ESTABLISHMENT_CAUSE_ENUM cause, srslte::unique_byte_buffer_t pdu); void initial_ue(uint16_t rnti, LIBLTE_S1AP_RRC_ESTABLISHMENT_CAUSE_ENUM cause, srslte::unique_byte_buffer_t pdu, uint32_t m_tmsi, uint8_t mmec); void write_pdu(uint16_t rnti, srslte::unique_byte_buffer_t pdu); bool user_exists(uint16_t rnti); bool user_release(uint16_t rnti, LIBLTE_S1AP_CAUSERADIONETWORK_ENUM cause_radio); void ue_ctxt_setup_complete(uint16_t rnti, LIBLTE_S1AP_MESSAGE_INITIALCONTEXTSETUPRESPONSE_STRUCT* res); void ue_erab_setup_complete(uint16_t rnti, LIBLTE_S1AP_MESSAGE_E_RABSETUPRESPONSE_STRUCT* res); bool is_mme_connected(); // void ue_capabilities(uint16_t rnti, LIBLTE_RRC_UE_EUTRA_CAPABILITY_STRUCT *caps); // Stack interface bool handle_mme_rx_msg(srslte::unique_byte_buffer_t pdu, const sockaddr_in& from, const sctp_sndrcvinfo& sri, int flags); private: static const int MME_PORT = 36412; static const int ADDR_FAMILY = AF_INET; static const int SOCK_TYPE = SOCK_STREAM; static const int PROTO = IPPROTO_SCTP; static const int PPID = 18; static const int NONUE_STREAM_ID = 0; // args rrc_interface_s1ap* rrc = nullptr; s1ap_args_t args; srslte::log* s1ap_log = nullptr; srslte::byte_buffer_pool* pool = nullptr; srsenb::stack_interface_s1ap_lte* stack = nullptr; srslte::socket_handler_t s1ap_socket; struct sockaddr_in mme_addr = {}; // MME address bool mme_connected = false; bool running = false; uint32_t next_eNB_UE_S1AP_ID = 1; // Next ENB-side UE identifier uint16_t next_ue_stream_id = 1; // Next UE SCTP stream identifier srslte::timer_handler::unique_timer mme_connect_timer, s1setup_timeout; // Protocol IEs sent with every UL S1AP message LIBLTE_S1AP_TAI_STRUCT tai; LIBLTE_S1AP_EUTRAN_CGI_STRUCT eutran_cgi; LIBLTE_S1AP_MESSAGE_S1SETUPRESPONSE_STRUCT s1setupresponse; void build_tai_cgi(); bool connect_mme(); bool setup_s1(); bool sctp_send_s1ap_pdu(LIBLTE_S1AP_S1AP_PDU_STRUCT* tx_pdu, uint32_t rnti, const char* procedure_name); bool handle_s1ap_rx_pdu(srslte::byte_buffer_t* pdu); bool handle_initiatingmessage(LIBLTE_S1AP_INITIATINGMESSAGE_STRUCT* msg); bool handle_successfuloutcome(LIBLTE_S1AP_SUCCESSFULOUTCOME_STRUCT* msg); bool handle_unsuccessfuloutcome(LIBLTE_S1AP_UNSUCCESSFULOUTCOME_STRUCT* msg); bool handle_paging(LIBLTE_S1AP_MESSAGE_PAGING_STRUCT* msg); bool handle_s1setupresponse(LIBLTE_S1AP_MESSAGE_S1SETUPRESPONSE_STRUCT* msg); bool handle_dlnastransport(LIBLTE_S1AP_MESSAGE_DOWNLINKNASTRANSPORT_STRUCT* msg); bool handle_initialctxtsetuprequest(LIBLTE_S1AP_MESSAGE_INITIALCONTEXTSETUPREQUEST_STRUCT* msg); bool handle_uectxtreleasecommand(LIBLTE_S1AP_MESSAGE_UECONTEXTRELEASECOMMAND_STRUCT* msg); bool handle_s1setupfailure(LIBLTE_S1AP_MESSAGE_S1SETUPFAILURE_STRUCT* msg); bool handle_erabsetuprequest(LIBLTE_S1AP_MESSAGE_E_RABSETUPREQUEST_STRUCT* msg); bool handle_uecontextmodifyrequest(LIBLTE_S1AP_MESSAGE_UECONTEXTMODIFICATIONREQUEST_STRUCT* msg); bool send_initialuemessage(uint16_t rnti, LIBLTE_S1AP_RRC_ESTABLISHMENT_CAUSE_ENUM cause, srslte::unique_byte_buffer_t pdu, bool has_tmsi, uint32_t m_tmsi = 0, uint8_t mmec = 0); bool send_ulnastransport(uint16_t rnti, srslte::unique_byte_buffer_t pdu); bool send_uectxtreleaserequest(uint16_t rnti, LIBLTE_S1AP_CAUSE_STRUCT* cause); bool send_uectxtreleasecomplete(uint16_t rnti, uint32_t mme_ue_id, uint32_t enb_ue_id); bool send_initial_ctxt_setup_response(uint16_t rnti, LIBLTE_S1AP_MESSAGE_INITIALCONTEXTSETUPRESPONSE_STRUCT* res_); bool send_initial_ctxt_setup_failure(uint16_t rnti); bool send_erab_setup_response(uint16_t rnti, LIBLTE_S1AP_MESSAGE_E_RABSETUPRESPONSE_STRUCT* res_); // bool send_ue_capabilities(uint16_t rnti, LIBLTE_RRC_UE_EUTRA_CAPABILITY_STRUCT *caps) bool send_uectxmodifyresp(uint16_t rnti); bool send_uectxmodifyfailure(uint16_t rnti, LIBLTE_S1AP_CAUSE_STRUCT* cause); // handover bool send_ho_required(uint16_t rnti, uint32_t target_eci, srslte::plmn_id_t target_plmn, srslte::unique_byte_buffer_t rrc_container); bool handle_hopreparationfailure(LIBLTE_S1AP_MESSAGE_HANDOVERPREPARATIONFAILURE_STRUCT* msg); bool find_mme_ue_id(uint32_t mme_ue_id, uint16_t* rnti, uint32_t* enb_ue_id); std::string get_cause(const LIBLTE_S1AP_CAUSE_STRUCT* c); // UE-specific data and procedures struct ue { class ho_prep_proc_t { public: struct ts1_reloc_prep_expired { }; ho_prep_proc_t(s1ap::ue* ue_); srslte::proc_outcome_t init(uint32_t target_eci_, srslte::plmn_id_t target_plmn_, srslte::unique_byte_buffer_t rrc_container); srslte::proc_outcome_t step() { return srslte::proc_outcome_t::yield; } srslte::proc_outcome_t react(ts1_reloc_prep_expired e); srslte::proc_outcome_t react(const LIBLTE_S1AP_MESSAGE_HANDOVERPREPARATIONFAILURE_STRUCT& msg); void then(const srslte::proc_state_t& result); const char* name() { return "HandoverPreparation"; } private: s1ap::ue* ue_ptr = nullptr; s1ap* s1ap_ptr = nullptr; uint32_t target_eci = 0; srslte::plmn_id_t target_plmn; }; explicit ue(uint16_t rnti, s1ap* s1ap_ptr_); ue_ctxt_t& get_ctxt() { return ctxt; } srslte::proc_t& get_ho_prep_proc() { return ho_prep_proc; } private: bool send_ho_required(uint32_t target_eci_, srslte::plmn_id_t target_plmn_, srslte::unique_byte_buffer_t rrc_container); s1ap* s1ap_ptr; srslte::log* s1ap_log; ue_ctxt_t ctxt = {}; srslte::timer_handler::unique_timer ts1_reloc_prep; ///< TS1_{RELOCprep} - max time for HO preparation // user procedures srslte::proc_t ho_prep_proc; }; std::map > users; std::map enbid_to_rnti_map; ue_ctxt_t* get_user_ctxt(uint16_t rnti); // timers srslte::timer_handler* timers = nullptr; // procedures class s1_setup_proc_t { public: struct s1setupresult { bool success = false; enum class cause_t { timeout, failure } cause; }; explicit s1_setup_proc_t(s1ap* s1ap_) : s1ap_ptr(s1ap_) {} srslte::proc_outcome_t init(); srslte::proc_outcome_t step() { return srslte::proc_outcome_t::yield; } srslte::proc_outcome_t react(const s1setupresult& event); void then(const srslte::proc_state_t& result) const; const char* name() const { return "MME Connection"; } private: srslte::proc_outcome_t start_mme_connection(); s1ap* s1ap_ptr = nullptr; }; srslte::proc_t s1setup_proc; }; } // namespace srsenb #endif // SRSENB_S1AP_H