/** * Copyright 2013-2021 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 SRSRAN_PDCP_ENTITY_BASE_H #define SRSRAN_PDCP_ENTITY_BASE_H #include "srsran/adt/accumulators.h" #include "srsran/common/buffer_pool.h" #include "srsran/common/common.h" #include "srsran/common/interfaces_common.h" #include "srsran/common/security.h" #include "srsran/common/task_scheduler.h" #include "srsran/common/threads.h" #include "srsran/common/timers.h" #include "srsran/interfaces/pdcp_interface_types.h" #include "srsran/upper/byte_buffer_queue.h" #include "srsran/upper/pdcp_metrics.h" namespace srsran { /**************************************************************************** * Structs and Defines common to both LTE and NR * Ref: 3GPP TS 36.323 v10.1.0 and TS 38.323 v15.2.0 ***************************************************************************/ #define PDCP_PDU_TYPE_PDCP_STATUS_REPORT 0x0 #define PDCP_PDU_TYPE_INTERSPERSED_ROHC_FEEDBACK_PACKET 0x1 // Maximum supported PDCP SDU size is 9000 bytes. // See TS 38.323 v15.2.0, section 4.3.1 #define PDCP_MAX_SDU_SIZE 9000 typedef enum { PDCP_D_C_CONTROL_PDU = 0, PDCP_D_C_DATA_PDU, PDCP_D_C_N_ITEMS, } pdcp_d_c_t; static const char pdcp_d_c_text[PDCP_D_C_N_ITEMS][20] = {"Control PDU", "Data PDU"}; /**************************************************************************** * PDCP Entity interface * Common interface for LTE and NR PDCP entities ***************************************************************************/ class pdcp_entity_base { public: pdcp_entity_base(task_sched_handle task_sched_, srslog::basic_logger& logger); pdcp_entity_base(pdcp_entity_base&&) = default; virtual ~pdcp_entity_base(); virtual bool configure(const pdcp_config_t& cnfg_) = 0; virtual void reset() = 0; virtual void reestablish() = 0; bool is_active() { return active; } bool is_srb() { return cfg.rb_type == PDCP_RB_IS_SRB; } bool is_drb() { return cfg.rb_type == PDCP_RB_IS_DRB; } // RRC interface void enable_integrity(srsran_direction_t direction = DIRECTION_TXRX) { // if either DL or UL is already enabled, both are enabled if (integrity_direction == DIRECTION_TX && direction == DIRECTION_RX) { integrity_direction = DIRECTION_TXRX; } else if (integrity_direction == DIRECTION_RX && direction == DIRECTION_TX) { integrity_direction = DIRECTION_TXRX; } else { integrity_direction = direction; } logger.debug("LCID=%d, integrity=%s", lcid, srsran_direction_text[integrity_direction]); } void enable_encryption(srsran_direction_t direction = DIRECTION_TXRX) { // if either DL or UL is already enabled, both are enabled if (encryption_direction == DIRECTION_TX && direction == DIRECTION_RX) { encryption_direction = DIRECTION_TXRX; } else if (encryption_direction == DIRECTION_RX && direction == DIRECTION_TX) { encryption_direction = DIRECTION_TXRX; } else { encryption_direction = direction; } logger.debug("LCID=%d encryption=%s", lcid, srsran_direction_text[integrity_direction]); } void enable_security_timed(srsran_direction_t direction, uint32_t sn) { switch (direction) { case DIRECTION_TX: enable_security_tx_sn = sn; break; case DIRECTION_RX: enable_security_rx_sn = sn; break; default: logger.error("Timed security activation for direction %s not supported.", srsran_direction_text[direction]); break; } } void config_security(as_security_config_t sec_cfg_); // GW/SDAP/RRC interface virtual void write_sdu(unique_byte_buffer_t sdu, int sn = -1) = 0; // RLC interface virtual void write_pdu(unique_byte_buffer_t pdu) = 0; virtual void notify_delivery(const pdcp_sn_vector_t& pdcp_sns) = 0; virtual void notify_failure(const pdcp_sn_vector_t& pdcp_sns) = 0; virtual void get_bearer_state(pdcp_lte_state_t* state) = 0; virtual void set_bearer_state(const pdcp_lte_state_t& state, bool set_fmc) = 0; virtual std::map get_buffered_pdus() = 0; virtual void send_status_report() = 0; // COUNT, HFN and SN helpers uint32_t HFN(uint32_t count); uint32_t SN(uint32_t count); uint32_t COUNT(uint32_t hfn, uint32_t sn); // Metrics helpers virtual pdcp_bearer_metrics_t get_metrics() = 0; virtual void reset_metrics() = 0; protected: srslog::basic_logger& logger; srsran::task_sched_handle task_sched; bool active = false; uint32_t lcid = 0; srsran_direction_t integrity_direction = DIRECTION_NONE; srsran_direction_t encryption_direction = DIRECTION_NONE; int32_t enable_security_tx_sn = -1; // TX SN at which security will be enabled int32_t enable_security_rx_sn = -1; // RX SN at which security will be enabled pdcp_config_t cfg = {1, PDCP_RB_IS_DRB, SECURITY_DIRECTION_DOWNLINK, SECURITY_DIRECTION_UPLINK, PDCP_SN_LEN_12, pdcp_t_reordering_t::ms500, pdcp_discard_timer_t::infinity, false}; srsran::as_security_config_t sec_cfg = {}; // Security functions void integrity_generate(uint8_t* msg, uint32_t msg_len, uint32_t count, uint8_t* mac); bool integrity_verify(uint8_t* msg, uint32_t msg_len, uint32_t count, uint8_t* mac); void cipher_encrypt(uint8_t* msg, uint32_t msg_len, uint32_t count, uint8_t* ct); void cipher_decrypt(uint8_t* ct, uint32_t ct_len, uint32_t count, uint8_t* msg); // Common packing functions bool is_control_pdu(const unique_byte_buffer_t& pdu); pdcp_pdu_type_t get_control_pdu_type(const unique_byte_buffer_t& pdu); uint32_t read_data_header(const unique_byte_buffer_t& pdu); void discard_data_header(const unique_byte_buffer_t& pdu); void write_data_header(const srsran::unique_byte_buffer_t& sdu, uint32_t count); void extract_mac(const unique_byte_buffer_t& pdu, uint8_t* mac); void append_mac(const unique_byte_buffer_t& sdu, uint8_t* mac); // Metrics helpers pdcp_bearer_metrics_t metrics = {}; srsran::rolling_average tx_pdu_ack_latency_ms; }; inline uint32_t pdcp_entity_base::HFN(uint32_t count) { return (count >> cfg.sn_len); } inline uint32_t pdcp_entity_base::SN(uint32_t count) { return count & (0xFFFFFFFF >> (32 - cfg.sn_len)); } inline uint32_t pdcp_entity_base::COUNT(uint32_t hfn, uint32_t sn) { return (hfn << cfg.sn_len) | sn; } } // namespace srsran #endif // SRSRAN_PDCP_ENTITY_BASE_H