/* * crc32.h * See linux/lib/crc32.c for license and changes */ #ifndef _LINUX_CRC32_H #define _LINUX_CRC32_H #include <linux/types.h> #include <linux/bitrev.h> u32 __pure crc32_le(u32 crc, unsigned char const *p, size_t len); u32 __pure crc32_be(u32 crc, unsigned char const *p, size_t len); /** * crc32_le_combine - Combine two crc32 check values into one. For two * sequences of bytes, seq1 and seq2 with lengths len1 * and len2, crc32_le() check values were calculated * for each, crc1 and crc2. * * @crc1: crc32 of the first block * @crc2: crc32 of the second block * @len2: length of the second block * * Return: The crc32_le() check value of seq1 and seq2 concatenated, * requiring only crc1, crc2, and len2. Note: If seq_full denotes * the concatenated memory area of seq1 with seq2, and crc_full * the crc32_le() value of seq_full, then crc_full == * crc32_le_combine(crc1, crc2, len2) when crc_full was seeded * with the same initializer as crc1, and crc2 seed was 0. See * also crc32_combine_test(). */ u32 __attribute_const__ crc32_le_shift(u32 crc, size_t len); static inline u32 crc32_le_combine(u32 crc1, u32 crc2, size_t len2) { return crc32_le_shift(crc1, len2) ^ crc2; } u32 __pure __crc32c_le(u32 crc, unsigned char const *p, size_t len); /** * __crc32c_le_combine - Combine two crc32c check values into one. For two * sequences of bytes, seq1 and seq2 with lengths len1 * and len2, __crc32c_le() check values were calculated * for each, crc1 and crc2. * * @crc1: crc32c of the first block * @crc2: crc32c of the second block * @len2: length of the second block * * Return: The __crc32c_le() check value of seq1 and seq2 concatenated, * requiring only crc1, crc2, and len2. Note: If seq_full denotes * the concatenated memory area of seq1 with seq2, and crc_full * the __crc32c_le() value of seq_full, then crc_full == * __crc32c_le_combine(crc1, crc2, len2) when crc_full was * seeded with the same initializer as crc1, and crc2 seed * was 0. See also crc32c_combine_test(). */ u32 __attribute_const__ __crc32c_le_shift(u32 crc, size_t len); static inline u32 __crc32c_le_combine(u32 crc1, u32 crc2, size_t len2) { return __crc32c_le_shift(crc1, len2) ^ crc2; } #define crc32(seed, data, length) crc32_le(seed, (unsigned char const *)(data), length) /* * Helpers for hash table generation of ethernet nics: * * Ethernet sends the least significant bit of a byte first, thus crc32_le * is used. The output of crc32_le is bit reversed [most significant bit * is in bit nr 0], thus it must be reversed before use. Except for * nics that bit swap the result internally... */ #define ether_crc(length, data) bitrev32(crc32_le(~0, data, length)) #define ether_crc_le(length, data) crc32_le(~0, data, length) #endif /* _LINUX_CRC32_H */