diff --git a/dist/tools/codespell/ignored_words.txt b/dist/tools/codespell/ignored_words.txt index 35bd1e1049f8..6a91d33f894d 100644 --- a/dist/tools/codespell/ignored_words.txt +++ b/dist/tools/codespell/ignored_words.txt @@ -147,3 +147,6 @@ nam # donot (part of bloom filter test vector) => do not donot + +# Didi (Ayman El Didi) => Did +didi diff --git a/makefiles/pseudomodules.inc.mk b/makefiles/pseudomodules.inc.mk index 1b43208dffbe..c88d5782dcde 100644 --- a/makefiles/pseudomodules.inc.mk +++ b/makefiles/pseudomodules.inc.mk @@ -45,6 +45,7 @@ PSEUDOMODULES += cortexm_fpu PSEUDOMODULES += cortexm_svc PSEUDOMODULES += cpp PSEUDOMODULES += cpu_check_address +PSEUDOMODULES += crc32_fast PSEUDOMODULES += credman_load PSEUDOMODULES += dbgpin PSEUDOMODULES += devfs_% diff --git a/sys/Makefile.dep b/sys/Makefile.dep index b24eef8d08e3..bdd95cf64e71 100644 --- a/sys/Makefile.dep +++ b/sys/Makefile.dep @@ -49,6 +49,10 @@ ifneq (,$(filter congure_reno_methods,$(USEMODULE))) USEMODULE += seq endif +ifneq (,$(filter crc32_fast,$(USEMODULE))) + USEMODULE += checksum +endif + ifneq (,$(filter eepreg,$(USEMODULE))) FEATURES_REQUIRED += periph_eeprom endif diff --git a/sys/checksum/crc32.c b/sys/checksum/crc32.c new file mode 100644 index 000000000000..2a2ca8206c2c --- /dev/null +++ b/sys/checksum/crc32.c @@ -0,0 +1,120 @@ +/* + * Copyright (C) 2020 Ayman El Didi + * + * To the extent possible under law, the author(s) have dedicated all + * domain worldwide. This software is distributed without any warranty. + * + * You should have received a copy of the CC0 Public Domain Dedication along + * with this software. If not, see http://creativecommons.org/publicdomain/zero/1.0/ + */ + +/** + * @{ + * + * @file + * @author Ayman El Didi + * @author Benjamin Valentin + */ + +#include "kernel_defines.h" +#include "checksum/crc32.h" + +const uint32_t crc32_tab[] = { + 0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, + 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, + 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2, + 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7, + 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, + 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, + 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c, + 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59, + 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, + 0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, + 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106, + 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433, + 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, + 0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, + 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950, + 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65, + 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, + 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, + 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa, + 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f, + 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, + 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, + 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84, + 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1, + 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, + 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, + 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e, + 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b, + 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, + 0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, + 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28, + 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d, + 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, + 0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, + 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242, + 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777, + 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, + 0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, + 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc, + 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9, + 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, + 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, + 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d +}; + +static inline uint32_t crc32_for_byte(uint32_t result) +{ + if (IS_USED(MODULE_CRC32_FAST)) { + return crc32_tab[result & 0xFF] ^ (result >> 8); + } + + const uint32_t polynomial = 0xEDB88320L; + + for (unsigned i = 0; i < 8; i++) { + /* IMPLEMENTATION: the code below always shifts result right by + * 1, but only XORs it by the polynomial if we're on the lowest + * bit. + * + * This is because 1 in binary is 00000001, so ANDing the + * result by 1 will always give 0 unless the lowest bit is set. + * And since XOR by zero does nothing, the other half only + * occurs when we're on the lowest bit. + * + * I didn't leave the above implementation in, despite being + * faster on my machine since it is a more complex operation + * which may be slower on less sophisticated processors. It can + * be added in in place of the loop code below. + */ + + result = (result >> 1) ^ (result & 1) * polynomial; + + /* Here is the code I replaced with the branch I tried to + * remove: + if (result & 1) { + result = (result >> 1) ^ polynomial; + continue; + } + result >>= 1; + */ + } + return result; +} + +uint32_t crc32(const void *buf, size_t size) +{ + const uint8_t *p = buf; + uint32_t crc = ~0U; + + for (unsigned i = 0; i < size; ++i) { + crc ^= *p++; + crc = crc32_for_byte(crc); + + } + + return ~crc; +} + +/** @} */ diff --git a/sys/include/checksum/crc32.h b/sys/include/checksum/crc32.h new file mode 100644 index 000000000000..be5c1f1c7ac8 --- /dev/null +++ b/sys/include/checksum/crc32.h @@ -0,0 +1,51 @@ +/* + * Copyright (C) 2022 ML!PA Consulting GmbH + * + * This file is subject to the terms and conditions of the GNU Lesser + * General Public License v2.1. See the file LICENSE in the top level + * directory for more details. + */ + +/** + * @defgroup sys_checksum_crc32 CRC32 + * @ingroup sys_checksum + * + * @brief CRC32 checksum algorithm implementation according to IEEE standards + * @{ + * + * @file + * @author Benjamin Valentin + */ + +#ifndef CHECKSUM_CRC32_H +#define CHECKSUM_CRC32_H + +#include +#include + +#ifdef __cplusplus +extern "C" { +#endif + +/** + * @brief CRC-32 checksum + * + * Uses the `0xedb88320` polynomial + * + * @note enable the `crc32_fast` module for a look-up table based implementation + * that trades code size for speed. + * + * @param[in] buf The data to checksum + * @param[in] size Length of the data in bytes + * + * @return 32 bit sized hash in the interval [0..2^32] + */ +uint32_t crc32(const void *buf, size_t size); + +#ifdef __cplusplus +} +#endif + +#endif /* CHECKSUM_CRC32_H */ + +/** @} */ diff --git a/tests/unittests/tests-checksum/tests-checksum-crc32.c b/tests/unittests/tests-checksum/tests-checksum-crc32.c new file mode 100644 index 000000000000..49b2ed8c7cca --- /dev/null +++ b/tests/unittests/tests-checksum/tests-checksum-crc32.c @@ -0,0 +1,72 @@ +/* + * Copyright 2022 Benjamin Valentin + * + * This file is subject to the terms and conditions of the GNU Lesser + * General Public License v2.1. See the file LICENSE in the top level + * directory for more details. + */ + +#include "checksum/crc32.h" +#include "tests-checksum.h" + +static void test_checksum_crc32_sequence_empty(void) +{ + unsigned char buf[] = ""; + uint32_t expect = 0x0; + + TEST_ASSERT_EQUAL_INT(expect, crc32(buf, sizeof(buf) - 1)); +} + +static void test_checksum_crc32_sequence_1a(void) +{ + unsigned char buf[] = "A"; + uint32_t expect = 0xd3d99e8b; + + TEST_ASSERT_EQUAL_INT(expect, crc32(buf, sizeof(buf) - 1)); +} + +static void test_checksum_crc32_sequence_256a(void) +{ + unsigned char buf[] = "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" + "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" + "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" + "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" + "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" + "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" + "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA" + "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA"; + uint32_t expect = 0x49975b13; + + TEST_ASSERT_EQUAL_INT(expect, crc32(buf, sizeof(buf) - 1)); +} + +static void test_checksum_crc32_sequence_1to9(void) +{ + unsigned char buf[] = "123456789"; + uint32_t expect = 0xcbf43926; + + TEST_ASSERT_EQUAL_INT(expect, crc32(buf, sizeof(buf) - 1)); +} + +static void test_checksum_crc32_sequence_4bytes(void) +{ + unsigned char buf[] = { 0x12, 0x34, 0x56, 0x78 }; + uint32_t expect = 0x4a090e98; + + TEST_ASSERT_EQUAL_INT(expect, crc32(buf, sizeof(buf))); +} + +Test *tests_checksum_crc32_tests(void) +{ + EMB_UNIT_TESTFIXTURES(fixtures) { + new_TestFixture(test_checksum_crc32_sequence_empty), + new_TestFixture(test_checksum_crc32_sequence_1a), + new_TestFixture(test_checksum_crc32_sequence_256a), + new_TestFixture(test_checksum_crc32_sequence_1to9), + new_TestFixture(test_checksum_crc32_sequence_4bytes), + }; + + EMB_UNIT_TESTCALLER(checksum_crc32_tests, NULL, NULL, fixtures); + + return (Test *)&checksum_crc32_tests; +} diff --git a/tests/unittests/tests-checksum/tests-checksum.c b/tests/unittests/tests-checksum/tests-checksum.c index 9ed7eb2a43e8..93aa035c9dee 100644 --- a/tests/unittests/tests-checksum/tests-checksum.c +++ b/tests/unittests/tests-checksum/tests-checksum.c @@ -15,6 +15,7 @@ void tests_checksum(void) TESTS_RUN(tests_checksum_crc16_ccitt_mcrf4xx_tests()); TESTS_RUN(tests_checksum_crc16_ccitt_aug_tests()); TESTS_RUN(tests_checksum_crc16_ccitt_false_tests()); + TESTS_RUN(tests_checksum_crc32_tests()); TESTS_RUN(tests_checksum_fletcher16_tests()); TESTS_RUN(tests_checksum_fletcher32_tests()); TESTS_RUN(tests_checksum_ucrc16_tests()); diff --git a/tests/unittests/tests-checksum/tests-checksum.h b/tests/unittests/tests-checksum/tests-checksum.h index b6c68fca26d2..48999035bdcc 100644 --- a/tests/unittests/tests-checksum/tests-checksum.h +++ b/tests/unittests/tests-checksum/tests-checksum.h @@ -64,6 +64,13 @@ Test *tests_checksum_crc16_ccitt_false_tests(void); */ Test *tests_checksum_crc16_ccitt_aug_tests(void); +/** + * @brief Generates tests for checksum/crc32.h + * + * @return embUnit tests if successful, NULL if not. + */ +Test *tests_checksum_crc32_tests(void); + /** * @brief Generates tests for checksum/fletcher16.h *