/* * 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/. * */ /********************************************************************************************** * File: convcoder.h * * Description: Cyclic Redundancy Check * LTE requires CRC lengths 8, 16, 24A and 24B, each with it's own generator * polynomial. * * Reference: 3GPP TS 36.212 version 10.0.0 Release 10 Sec. 5.1.1 *********************************************************************************************/ #ifndef SRSLTE_CRC_H #define SRSLTE_CRC_H #include "srslte/config.h" #include typedef struct SRSLTE_API { uint64_t table[256]; int polynom; int order; uint64_t crcinit; uint64_t crcmask; uint64_t crchighbit; uint32_t srslte_crc_out; } srslte_crc_t; SRSLTE_API int srslte_crc_init(srslte_crc_t* h, uint32_t srslte_crc_poly, int srslte_crc_order); SRSLTE_API int srslte_crc_set_init(srslte_crc_t* h, uint64_t init_value); SRSLTE_API uint32_t srslte_crc_attach(srslte_crc_t* h, uint8_t* data, int len); SRSLTE_API uint32_t srslte_crc_attach_byte(srslte_crc_t* h, uint8_t* data, int len); static inline void srslte_crc_checksum_put_byte(srslte_crc_t* h, uint8_t byte) { // Polynom order 8, 16, 24 or 32 only. int ord = h->order - 8; uint64_t crc = h->crcinit; crc = (crc << 8) ^ h->table[((crc >> (ord)) & 0xff) ^ byte]; h->crcinit = crc; } static inline uint64_t srslte_crc_checksum_get(srslte_crc_t* h) { return (h->crcinit & h->crcmask); } SRSLTE_API uint32_t srslte_crc_checksum_byte(srslte_crc_t* h, uint8_t* data, int len); SRSLTE_API uint32_t srslte_crc_checksum(srslte_crc_t* h, uint8_t* data, int len); #endif // SRSLTE_CRC_H