1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Common values and helper functions for the NHPoly1305 hash function. 4 */ 5 6 #ifndef _NHPOLY1305_H 7 #define _NHPOLY1305_H 8 9 #include <crypto/hash.h> 10 #include <crypto/poly1305.h> 11 12 /* NH parameterization: */ 13 14 /* Endianness: little */ 15 /* Word size: 32 bits (works well on NEON, SSE2, AVX2) */ 16 17 /* Stride: 2 words (optimal on ARM32 NEON; works okay on other CPUs too) */ 18 #define NH_PAIR_STRIDE 2 19 #define NH_MESSAGE_UNIT (NH_PAIR_STRIDE * 2 * sizeof(u32)) 20 21 /* Num passes (Toeplitz iteration count): 4, to give ε = 2^{-128} */ 22 #define NH_NUM_PASSES 4 23 #define NH_HASH_BYTES (NH_NUM_PASSES * sizeof(u64)) 24 25 /* Max message size: 1024 bytes (32x compression factor) */ 26 #define NH_NUM_STRIDES 64 27 #define NH_MESSAGE_WORDS (NH_PAIR_STRIDE * 2 * NH_NUM_STRIDES) 28 #define NH_MESSAGE_BYTES (NH_MESSAGE_WORDS * sizeof(u32)) 29 #define NH_KEY_WORDS (NH_MESSAGE_WORDS + \ 30 NH_PAIR_STRIDE * 2 * (NH_NUM_PASSES - 1)) 31 #define NH_KEY_BYTES (NH_KEY_WORDS * sizeof(u32)) 32 33 #define NHPOLY1305_KEY_SIZE (POLY1305_BLOCK_SIZE + NH_KEY_BYTES) 34 35 struct nhpoly1305_key { 36 struct poly1305_key poly_key; 37 u32 nh_key[NH_KEY_WORDS]; 38 }; 39 40 struct nhpoly1305_state { 41 42 /* Running total of polynomial evaluation */ 43 struct poly1305_state poly_state; 44 45 /* Partial block buffer */ 46 u8 buffer[NH_MESSAGE_UNIT]; 47 unsigned int buflen; 48 49 /* 50 * Number of bytes remaining until the current NH message reaches 51 * NH_MESSAGE_BYTES. When nonzero, 'nh_hash' holds the partial NH hash. 52 */ 53 unsigned int nh_remaining; 54 55 __le64 nh_hash[NH_NUM_PASSES]; 56 }; 57 58 typedef void (*nh_t)(const u32 *key, const u8 *message, size_t message_len, 59 __le64 hash[NH_NUM_PASSES]); 60 61 int crypto_nhpoly1305_setkey(struct crypto_shash *tfm, 62 const u8 *key, unsigned int keylen); 63 64 int crypto_nhpoly1305_init(struct shash_desc *desc); 65 int crypto_nhpoly1305_update(struct shash_desc *desc, 66 const u8 *src, unsigned int srclen); 67 int crypto_nhpoly1305_update_helper(struct shash_desc *desc, 68 const u8 *src, unsigned int srclen, 69 nh_t nh_fn); 70 int crypto_nhpoly1305_final(struct shash_desc *desc, u8 *dst); 71 int crypto_nhpoly1305_final_helper(struct shash_desc *desc, u8 *dst, 72 nh_t nh_fn); 73 74 #endif /* _NHPOLY1305_H */ 75