| /* Copyright (C) 2016 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. |
| * |
| * This file is provided under a dual BSD/GPLv2 license. |
| * |
| * SipHash: a fast short-input PRF |
| * https://131002.net/siphash/ |
| * |
| * This implementation is specifically for SipHash2-4 for a secure PRF |
| * and HalfSipHash1-3/SipHash1-3 for an insecure PRF only suitable for |
| * hashtables. |
| */ |
| |
| #ifndef _LINUX_SIPHASH_H |
| #define _LINUX_SIPHASH_H |
| |
| #include <linux/types.h> |
| #include <linux/kernel.h> |
| |
| #define SIPHASH_ALIGNMENT __alignof__(u64) |
| typedef struct { |
| u64 key[2]; |
| } siphash_key_t; |
| |
| static inline bool siphash_key_is_zero(const siphash_key_t *key) |
| { |
| return !(key->key[0] | key->key[1]); |
| } |
| |
| u64 __siphash_aligned(const void *data, size_t len, const siphash_key_t *key); |
| u64 __siphash_unaligned(const void *data, size_t len, const siphash_key_t *key); |
| |
| u64 siphash_1u64(const u64 a, const siphash_key_t *key); |
| u64 siphash_2u64(const u64 a, const u64 b, const siphash_key_t *key); |
| u64 siphash_3u64(const u64 a, const u64 b, const u64 c, |
| const siphash_key_t *key); |
| u64 siphash_4u64(const u64 a, const u64 b, const u64 c, const u64 d, |
| const siphash_key_t *key); |
| u64 siphash_1u32(const u32 a, const siphash_key_t *key); |
| u64 siphash_3u32(const u32 a, const u32 b, const u32 c, |
| const siphash_key_t *key); |
| |
| static inline u64 siphash_2u32(const u32 a, const u32 b, |
| const siphash_key_t *key) |
| { |
| return siphash_1u64((u64)b << 32 | a, key); |
| } |
| static inline u64 siphash_4u32(const u32 a, const u32 b, const u32 c, |
| const u32 d, const siphash_key_t *key) |
| { |
| return siphash_2u64((u64)b << 32 | a, (u64)d << 32 | c, key); |
| } |
| |
| |
| static inline u64 ___siphash_aligned(const __le64 *data, size_t len, |
| const siphash_key_t *key) |
| { |
| if (__builtin_constant_p(len) && len == 4) |
| return siphash_1u32(le32_to_cpup((const __le32 *)data), key); |
| if (__builtin_constant_p(len) && len == 8) |
| return siphash_1u64(le64_to_cpu(data[0]), key); |
| if (__builtin_constant_p(len) && len == 16) |
| return siphash_2u64(le64_to_cpu(data[0]), le64_to_cpu(data[1]), |
| key); |
| if (__builtin_constant_p(len) && len == 24) |
| return siphash_3u64(le64_to_cpu(data[0]), le64_to_cpu(data[1]), |
| le64_to_cpu(data[2]), key); |
| if (__builtin_constant_p(len) && len == 32) |
| return siphash_4u64(le64_to_cpu(data[0]), le64_to_cpu(data[1]), |
| le64_to_cpu(data[2]), le64_to_cpu(data[3]), |
| key); |
| return __siphash_aligned(data, len, key); |
| } |
| |
| /** |
| * siphash - compute 64-bit siphash PRF value |
| * @data: buffer to hash |
| * @size: size of @data |
| * @key: the siphash key |
| */ |
| static inline u64 siphash(const void *data, size_t len, |
| const siphash_key_t *key) |
| { |
| if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) || |
| !IS_ALIGNED((unsigned long)data, SIPHASH_ALIGNMENT)) |
| return __siphash_unaligned(data, len, key); |
| return ___siphash_aligned(data, len, key); |
| } |
| |
| #define HSIPHASH_ALIGNMENT __alignof__(unsigned long) |
| typedef struct { |
| unsigned long key[2]; |
| } hsiphash_key_t; |
| |
| u32 __hsiphash_aligned(const void *data, size_t len, |
| const hsiphash_key_t *key); |
| u32 __hsiphash_unaligned(const void *data, size_t len, |
| const hsiphash_key_t *key); |
| |
| u32 hsiphash_1u32(const u32 a, const hsiphash_key_t *key); |
| u32 hsiphash_2u32(const u32 a, const u32 b, const hsiphash_key_t *key); |
| u32 hsiphash_3u32(const u32 a, const u32 b, const u32 c, |
| const hsiphash_key_t *key); |
| u32 hsiphash_4u32(const u32 a, const u32 b, const u32 c, const u32 d, |
| const hsiphash_key_t *key); |
| |
| static inline u32 ___hsiphash_aligned(const __le32 *data, size_t len, |
| const hsiphash_key_t *key) |
| { |
| if (__builtin_constant_p(len) && len == 4) |
| return hsiphash_1u32(le32_to_cpu(data[0]), key); |
| if (__builtin_constant_p(len) && len == 8) |
| return hsiphash_2u32(le32_to_cpu(data[0]), le32_to_cpu(data[1]), |
| key); |
| if (__builtin_constant_p(len) && len == 12) |
| return hsiphash_3u32(le32_to_cpu(data[0]), le32_to_cpu(data[1]), |
| le32_to_cpu(data[2]), key); |
| if (__builtin_constant_p(len) && len == 16) |
| return hsiphash_4u32(le32_to_cpu(data[0]), le32_to_cpu(data[1]), |
| le32_to_cpu(data[2]), le32_to_cpu(data[3]), |
| key); |
| return __hsiphash_aligned(data, len, key); |
| } |
| |
| /** |
| * hsiphash - compute 32-bit hsiphash PRF value |
| * @data: buffer to hash |
| * @size: size of @data |
| * @key: the hsiphash key |
| */ |
| static inline u32 hsiphash(const void *data, size_t len, |
| const hsiphash_key_t *key) |
| { |
| if (IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) || |
| !IS_ALIGNED((unsigned long)data, HSIPHASH_ALIGNMENT)) |
| return __hsiphash_unaligned(data, len, key); |
| return ___hsiphash_aligned(data, len, key); |
| } |
| |
| #endif /* _LINUX_SIPHASH_H */ |