From 26609a21a9460145e37d90947ad957b358a05288 Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Fri, 16 Nov 2018 17:26:29 -0800 Subject: crypto: nhpoly1305 - add NHPoly1305 support MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add a generic implementation of NHPoly1305, an ε-almost-∆-universal hash function used in the Adiantum encryption mode. CONFIG_NHPOLY1305 is not selectable by itself since there won't be any real reason to enable it without also enabling Adiantum support. Signed-off-by: Eric Biggers Acked-by: Ard Biesheuvel Signed-off-by: Herbert Xu --- include/crypto/nhpoly1305.h | 74 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 74 insertions(+) create mode 100644 include/crypto/nhpoly1305.h (limited to 'include/crypto') diff --git a/include/crypto/nhpoly1305.h b/include/crypto/nhpoly1305.h new file mode 100644 index 000000000000..53c04423c582 --- /dev/null +++ b/include/crypto/nhpoly1305.h @@ -0,0 +1,74 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Common values and helper functions for the NHPoly1305 hash function. + */ + +#ifndef _NHPOLY1305_H +#define _NHPOLY1305_H + +#include +#include + +/* NH parameterization: */ + +/* Endianness: little */ +/* Word size: 32 bits (works well on NEON, SSE2, AVX2) */ + +/* Stride: 2 words (optimal on ARM32 NEON; works okay on other CPUs too) */ +#define NH_PAIR_STRIDE 2 +#define NH_MESSAGE_UNIT (NH_PAIR_STRIDE * 2 * sizeof(u32)) + +/* Num passes (Toeplitz iteration count): 4, to give ε = 2^{-128} */ +#define NH_NUM_PASSES 4 +#define NH_HASH_BYTES (NH_NUM_PASSES * sizeof(u64)) + +/* Max message size: 1024 bytes (32x compression factor) */ +#define NH_NUM_STRIDES 64 +#define NH_MESSAGE_WORDS (NH_PAIR_STRIDE * 2 * NH_NUM_STRIDES) +#define NH_MESSAGE_BYTES (NH_MESSAGE_WORDS * sizeof(u32)) +#define NH_KEY_WORDS (NH_MESSAGE_WORDS + \ + NH_PAIR_STRIDE * 2 * (NH_NUM_PASSES - 1)) +#define NH_KEY_BYTES (NH_KEY_WORDS * sizeof(u32)) + +#define NHPOLY1305_KEY_SIZE (POLY1305_BLOCK_SIZE + NH_KEY_BYTES) + +struct nhpoly1305_key { + struct poly1305_key poly_key; + u32 nh_key[NH_KEY_WORDS]; +}; + +struct nhpoly1305_state { + + /* Running total of polynomial evaluation */ + struct poly1305_state poly_state; + + /* Partial block buffer */ + u8 buffer[NH_MESSAGE_UNIT]; + unsigned int buflen; + + /* + * Number of bytes remaining until the current NH message reaches + * NH_MESSAGE_BYTES. When nonzero, 'nh_hash' holds the partial NH hash. + */ + unsigned int nh_remaining; + + __le64 nh_hash[NH_NUM_PASSES]; +}; + +typedef void (*nh_t)(const u32 *key, const u8 *message, size_t message_len, + __le64 hash[NH_NUM_PASSES]); + +int crypto_nhpoly1305_setkey(struct crypto_shash *tfm, + const u8 *key, unsigned int keylen); + +int crypto_nhpoly1305_init(struct shash_desc *desc); +int crypto_nhpoly1305_update(struct shash_desc *desc, + const u8 *src, unsigned int srclen); +int crypto_nhpoly1305_update_helper(struct shash_desc *desc, + const u8 *src, unsigned int srclen, + nh_t nh_fn); +int crypto_nhpoly1305_final(struct shash_desc *desc, u8 *dst); +int crypto_nhpoly1305_final_helper(struct shash_desc *desc, u8 *dst, + nh_t nh_fn); + +#endif /* _NHPOLY1305_H */ -- cgit v1.2.3