| 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 | |
| 11 | u32 __pure crc32_le(u32 crc, unsigned char const *p, size_t len); |
| 12 | u32 __pure 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 | */ |
| 32 | u32 __attribute_const__ crc32_le_shift(u32 crc, size_t len); |
| 33 | |
| 34 | static inline u32 crc32_le_combine(u32 crc1, u32 crc2, size_t len2) |
| 35 | { |
| 36 | return crc32_le_shift(crc1, len2) ^ crc2; |
| 37 | } |
| 38 | |
| 39 | u32 __pure __crc32c_le(u32 crc, unsigned char const *p, size_t len); |
| 40 | |
| 41 | /** |
| 42 | * __crc32c_le_combine - Combine two crc32c check values into one. For two |
| 43 | * sequences of bytes, seq1 and seq2 with lengths len1 |
| 44 | * and len2, __crc32c_le() check values were calculated |
| 45 | * for each, crc1 and crc2. |
| 46 | * |
| 47 | * @crc1: crc32c of the first block |
| 48 | * @crc2: crc32c of the second block |
| 49 | * @len2: length of the second block |
| 50 | * |
| 51 | * Return: The __crc32c_le() check value of seq1 and seq2 concatenated, |
| 52 | * requiring only crc1, crc2, and len2. Note: If seq_full denotes |
| 53 | * the concatenated memory area of seq1 with seq2, and crc_full |
| 54 | * the __crc32c_le() value of seq_full, then crc_full == |
| 55 | * __crc32c_le_combine(crc1, crc2, len2) when crc_full was |
| 56 | * seeded with the same initializer as crc1, and crc2 seed |
| 57 | * was 0. See also crc32c_combine_test(). |
| 58 | */ |
| 59 | u32 __attribute_const__ __crc32c_le_shift(u32 crc, size_t len); |
| 60 | |
| 61 | static inline u32 __crc32c_le_combine(u32 crc1, u32 crc2, size_t len2) |
| 62 | { |
| 63 | return __crc32c_le_shift(crc1, len2) ^ crc2; |
| 64 | } |
| 65 | |
| 66 | #define crc32(seed, data, length) crc32_le(seed, (unsigned char const *)(data), length) |
| 67 | |
| 68 | /* |
| 69 | * Helpers for hash table generation of ethernet nics: |
| 70 | * |
| 71 | * Ethernet sends the least significant bit of a byte first, thus crc32_le |
| 72 | * is used. The output of crc32_le is bit reversed [most significant bit |
| 73 | * is in bit nr 0], thus it must be reversed before use. Except for |
| 74 | * nics that bit swap the result internally... |
| 75 | */ |
| 76 | #define ether_crc(length, data) bitrev32(crc32_le(~0, data, length)) |
| 77 | #define ether_crc_le(length, data) crc32_le(~0, data, length) |
| 78 | |
| 79 | #endif /* _LINUX_CRC32_H */ |