+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0
-/*
- * NHPoly1305 - ε-almost-∆-universal hash function for Adiantum
- *
- * Copyright 2018 Google LLC
- */
-
-/*
- * "NHPoly1305" is the main component of Adiantum hashing.
- * Specifically, it is the calculation
- *
- * H_L ← Poly1305_{K_L}(NH_{K_N}(pad_{128}(L)))
- *
- * from the procedure in section 6.4 of the Adiantum paper [1]. It is an
- * ε-almost-∆-universal (ε-∆U) hash function for equal-length inputs over
- * Z/(2^{128}Z), where the "∆" operation is addition. It hashes 1024-byte
- * chunks of the input with the NH hash function [2], reducing the input length
- * by 32x. The resulting NH digests are evaluated as a polynomial in
- * GF(2^{130}-5), like in the Poly1305 MAC [3]. Note that the polynomial
- * evaluation by itself would suffice to achieve the ε-∆U property; NH is used
- * for performance since it's over twice as fast as Poly1305.
- *
- * This is *not* a cryptographic hash function; do not use it as such!
- *
- * [1] Adiantum: length-preserving encryption for entry-level processors
- * (https://eprint.iacr.org/2018/720.pdf)
- * [2] UMAC: Fast and Secure Message Authentication
- * (https://fastcrypto.org/umac/umac_proc.pdf)
- * [3] The Poly1305-AES message-authentication code
- * (https://cr.yp.to/mac/poly1305-20050329.pdf)
- */
-
-#include <linux/unaligned.h>
-#include <crypto/algapi.h>
-#include <crypto/internal/hash.h>
-#include <crypto/internal/poly1305.h>
-#include <crypto/nhpoly1305.h>
-#include <linux/crypto.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-
-static void nh_generic(const u32 *key, const u8 *message, size_t message_len,
- __le64 hash[NH_NUM_PASSES])
-{
- u64 sums[4] = { 0, 0, 0, 0 };
-
- BUILD_BUG_ON(NH_PAIR_STRIDE != 2);
- BUILD_BUG_ON(NH_NUM_PASSES != 4);
-
- while (message_len) {
- u32 m0 = get_unaligned_le32(message + 0);
- u32 m1 = get_unaligned_le32(message + 4);
- u32 m2 = get_unaligned_le32(message + 8);
- u32 m3 = get_unaligned_le32(message + 12);
-
- sums[0] += (u64)(u32)(m0 + key[ 0]) * (u32)(m2 + key[ 2]);
- sums[1] += (u64)(u32)(m0 + key[ 4]) * (u32)(m2 + key[ 6]);
- sums[2] += (u64)(u32)(m0 + key[ 8]) * (u32)(m2 + key[10]);
- sums[3] += (u64)(u32)(m0 + key[12]) * (u32)(m2 + key[14]);
- sums[0] += (u64)(u32)(m1 + key[ 1]) * (u32)(m3 + key[ 3]);
- sums[1] += (u64)(u32)(m1 + key[ 5]) * (u32)(m3 + key[ 7]);
- sums[2] += (u64)(u32)(m1 + key[ 9]) * (u32)(m3 + key[11]);
- sums[3] += (u64)(u32)(m1 + key[13]) * (u32)(m3 + key[15]);
- key += NH_MESSAGE_UNIT / sizeof(key[0]);
- message += NH_MESSAGE_UNIT;
- message_len -= NH_MESSAGE_UNIT;
- }
-
- hash[0] = cpu_to_le64(sums[0]);
- hash[1] = cpu_to_le64(sums[1]);
- hash[2] = cpu_to_le64(sums[2]);
- hash[3] = cpu_to_le64(sums[3]);
-}
-
-/* Pass the next NH hash value through Poly1305 */
-static void process_nh_hash_value(struct nhpoly1305_state *state,
- const struct nhpoly1305_key *key)
-{
- BUILD_BUG_ON(NH_HASH_BYTES % POLY1305_BLOCK_SIZE != 0);
-
- poly1305_core_blocks(&state->poly_state, &key->poly_key, state->nh_hash,
- NH_HASH_BYTES / POLY1305_BLOCK_SIZE, 1);
-}
-
-/*
- * Feed the next portion of the source data, as a whole number of 16-byte
- * "NH message units", through NH and Poly1305. Each NH hash is taken over
- * 1024 bytes, except possibly the final one which is taken over a multiple of
- * 16 bytes up to 1024. Also, in the case where data is passed in misaligned
- * chunks, we combine partial hashes; the end result is the same either way.
- */
-static void nhpoly1305_units(struct nhpoly1305_state *state,
- const struct nhpoly1305_key *key,
- const u8 *src, unsigned int srclen, nh_t nh_fn)
-{
- do {
- unsigned int bytes;
-
- if (state->nh_remaining == 0) {
- /* Starting a new NH message */
- bytes = min_t(unsigned int, srclen, NH_MESSAGE_BYTES);
- nh_fn(key->nh_key, src, bytes, state->nh_hash);
- state->nh_remaining = NH_MESSAGE_BYTES - bytes;
- } else {
- /* Continuing a previous NH message */
- __le64 tmp_hash[NH_NUM_PASSES];
- unsigned int pos;
- int i;
-
- pos = NH_MESSAGE_BYTES - state->nh_remaining;
- bytes = min(srclen, state->nh_remaining);
- nh_fn(&key->nh_key[pos / 4], src, bytes, tmp_hash);
- for (i = 0; i < NH_NUM_PASSES; i++)
- le64_add_cpu(&state->nh_hash[i],
- le64_to_cpu(tmp_hash[i]));
- state->nh_remaining -= bytes;
- }
- if (state->nh_remaining == 0)
- process_nh_hash_value(state, key);
- src += bytes;
- srclen -= bytes;
- } while (srclen);
-}
-
-int crypto_nhpoly1305_setkey(struct crypto_shash *tfm,
- const u8 *key, unsigned int keylen)
-{
- struct nhpoly1305_key *ctx = crypto_shash_ctx(tfm);
- int i;
-
- if (keylen != NHPOLY1305_KEY_SIZE)
- return -EINVAL;
-
- poly1305_core_setkey(&ctx->poly_key, key);
- key += POLY1305_BLOCK_SIZE;
-
- for (i = 0; i < NH_KEY_WORDS; i++)
- ctx->nh_key[i] = get_unaligned_le32(key + i * sizeof(u32));
-
- return 0;
-}
-EXPORT_SYMBOL(crypto_nhpoly1305_setkey);
-
-int crypto_nhpoly1305_init(struct shash_desc *desc)
-{
- struct nhpoly1305_state *state = shash_desc_ctx(desc);
-
- poly1305_core_init(&state->poly_state);
- state->buflen = 0;
- state->nh_remaining = 0;
- return 0;
-}
-EXPORT_SYMBOL(crypto_nhpoly1305_init);
-
-int crypto_nhpoly1305_update_helper(struct shash_desc *desc,
- const u8 *src, unsigned int srclen,
- nh_t nh_fn)
-{
- struct nhpoly1305_state *state = shash_desc_ctx(desc);
- const struct nhpoly1305_key *key = crypto_shash_ctx(desc->tfm);
- unsigned int bytes;
-
- if (state->buflen) {
- bytes = min(srclen, (int)NH_MESSAGE_UNIT - state->buflen);
- memcpy(&state->buffer[state->buflen], src, bytes);
- state->buflen += bytes;
- if (state->buflen < NH_MESSAGE_UNIT)
- return 0;
- nhpoly1305_units(state, key, state->buffer, NH_MESSAGE_UNIT,
- nh_fn);
- state->buflen = 0;
- src += bytes;
- srclen -= bytes;
- }
-
- if (srclen >= NH_MESSAGE_UNIT) {
- bytes = round_down(srclen, NH_MESSAGE_UNIT);
- nhpoly1305_units(state, key, src, bytes, nh_fn);
- src += bytes;
- srclen -= bytes;
- }
-
- if (srclen) {
- memcpy(state->buffer, src, srclen);
- state->buflen = srclen;
- }
- return 0;
-}
-EXPORT_SYMBOL(crypto_nhpoly1305_update_helper);
-
-int crypto_nhpoly1305_update(struct shash_desc *desc,
- const u8 *src, unsigned int srclen)
-{
- return crypto_nhpoly1305_update_helper(desc, src, srclen, nh_generic);
-}
-EXPORT_SYMBOL(crypto_nhpoly1305_update);
-
-int crypto_nhpoly1305_final_helper(struct shash_desc *desc, u8 *dst, nh_t nh_fn)
-{
- struct nhpoly1305_state *state = shash_desc_ctx(desc);
- const struct nhpoly1305_key *key = crypto_shash_ctx(desc->tfm);
-
- if (state->buflen) {
- memset(&state->buffer[state->buflen], 0,
- NH_MESSAGE_UNIT - state->buflen);
- nhpoly1305_units(state, key, state->buffer, NH_MESSAGE_UNIT,
- nh_fn);
- }
-
- if (state->nh_remaining)
- process_nh_hash_value(state, key);
-
- poly1305_core_emit(&state->poly_state, NULL, dst);
- return 0;
-}
-EXPORT_SYMBOL(crypto_nhpoly1305_final_helper);
-
-int crypto_nhpoly1305_final(struct shash_desc *desc, u8 *dst)
-{
- return crypto_nhpoly1305_final_helper(desc, dst, nh_generic);
-}
-EXPORT_SYMBOL(crypto_nhpoly1305_final);
-
-static struct shash_alg nhpoly1305_alg = {
- .base.cra_name = "nhpoly1305",
- .base.cra_driver_name = "nhpoly1305-generic",
- .base.cra_priority = 100,
- .base.cra_ctxsize = sizeof(struct nhpoly1305_key),
- .base.cra_module = THIS_MODULE,
- .digestsize = POLY1305_DIGEST_SIZE,
- .init = crypto_nhpoly1305_init,
- .update = crypto_nhpoly1305_update,
- .final = crypto_nhpoly1305_final,
- .setkey = crypto_nhpoly1305_setkey,
- .descsize = sizeof(struct nhpoly1305_state),
-};
-
-static int __init nhpoly1305_mod_init(void)
-{
- return crypto_register_shash(&nhpoly1305_alg);
-}
-
-static void __exit nhpoly1305_mod_exit(void)
-{
- crypto_unregister_shash(&nhpoly1305_alg);
-}
-
-module_init(nhpoly1305_mod_init);
-module_exit(nhpoly1305_mod_exit);
-
-MODULE_DESCRIPTION("NHPoly1305 ε-almost-∆-universal hash function");
-MODULE_LICENSE("GPL v2");
-MODULE_AUTHOR("Eric Biggers <ebiggers@google.com>");
-MODULE_ALIAS_CRYPTO("nhpoly1305");
-MODULE_ALIAS_CRYPTO("nhpoly1305-generic");
+++ /dev/null
-/* SPDX-License-Identifier: GPL-2.0 */
-/*
- * Common values and helper functions for the NHPoly1305 hash function.
- */
-
-#ifndef _NHPOLY1305_H
-#define _NHPOLY1305_H
-
-#include <crypto/hash.h>
-#include <crypto/internal/poly1305.h>
-
-/* 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_core_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 */
projects / thirdparty / kernel / linux.git / commitdiff
