1/* 2 * crc32.h 3 * See linux/lib/crc32.c for license and changes 4 */ 5#ifndef _LINUX_CRC32_H 6#define _LINUX_CRC32_H 7 8#include <linux/types.h> 9#include <linux/bitrev.h> 10 11extern u32 crc32_le(u32 crc, unsigned char const *p, size_t len); 12extern u32 crc32_be(u32 crc, unsigned char const *p, size_t len); 13 14/** 15 * crc32_le_combine - Combine two crc32 check values into one. For two 16 * sequences of bytes, seq1 and seq2 with lengths len1 17 * and len2, crc32_le() check values were calculated 18 * for each, crc1 and crc2. 19 * 20 * @crc1: crc32 of the first block 21 * @crc2: crc32 of the second block 22 * @len2: length of the second block 23 * 24 * Return: The crc32_le() check value of seq1 and seq2 concatenated, 25 * requiring only crc1, crc2, and len2. Note: If seq_full denotes 26 * the concatenated memory area of seq1 with seq2, and crc_full 27 * the crc32_le() value of seq_full, then crc_full == 28 * crc32_le_combine(crc1, crc2, len2) when crc_full was seeded 29 * with the same initializer as crc1, and crc2 seed was 0. See 30 * also crc32_combine_test(). 31 */ 32extern u32 crc32_le_combine(u32 crc1, u32 crc2, size_t len2); 33 34extern u32 __crc32c_le(u32 crc, unsigned char const *p, size_t len); 35 36/** 37 * __crc32c_le_combine - Combine two crc32c check values into one. For two 38 * sequences of bytes, seq1 and seq2 with lengths len1 39 * and len2, __crc32c_le() check values were calculated 40 * for each, crc1 and crc2. 41 * 42 * @crc1: crc32c of the first block 43 * @crc2: crc32c of the second block 44 * @len2: length of the second block 45 * 46 * Return: The __crc32c_le() check value of seq1 and seq2 concatenated, 47 * requiring only crc1, crc2, and len2. Note: If seq_full denotes 48 * the concatenated memory area of seq1 with seq2, and crc_full 49 * the __crc32c_le() value of seq_full, then crc_full == 50 * __crc32c_le_combine(crc1, crc2, len2) when crc_full was 51 * seeded with the same initializer as crc1, and crc2 seed 52 * was 0. See also crc32c_combine_test(). 53 */ 54extern u32 __crc32c_le_combine(u32 crc1, u32 crc2, size_t len2); 55 56#define crc32(seed, data, length) crc32_le(seed, (unsigned char const *)(data), length) 57 58/* 59 * Helpers for hash table generation of ethernet nics: 60 * 61 * Ethernet sends the least significant bit of a byte first, thus crc32_le 62 * is used. The output of crc32_le is bit reversed [most significant bit 63 * is in bit nr 0], thus it must be reversed before use. Except for 64 * nics that bit swap the result internally... 65 */ 66#define ether_crc(length, data) bitrev32(crc32_le(~0, data, length)) 67#define ether_crc_le(length, data) crc32_le(~0, data, length) 68 69#endif /* _LINUX_CRC32_H */ 70