1// SPDX-License-Identifier: GPL-2.0
2/*
3 * NHPoly1305 - ε-almost-∆-universal hash function for Adiantum
4 * (NEON accelerated version)
5 *
6 * Copyright 2018 Google LLC
7 */
8
9#include <asm/neon.h>
10#include <asm/simd.h>
11#include <crypto/internal/hash.h>
12#include <crypto/internal/simd.h>
13#include <crypto/nhpoly1305.h>
14#include <linux/module.h>
15
16asmlinkage void nh_neon(const u32 *key, const u8 *message, size_t message_len,
17			__le64 hash[NH_NUM_PASSES]);
18
19static int nhpoly1305_neon_update(struct shash_desc *desc,
20				  const u8 *src, unsigned int srclen)
21{
22	if (srclen < 64 || !crypto_simd_usable())
23		return crypto_nhpoly1305_update(desc, src, srclen);
24
25	do {
26		unsigned int n = min_t(unsigned int, srclen, SZ_4K);
27
28		kernel_neon_begin();
29		crypto_nhpoly1305_update_helper(desc, src, n, nh_neon);
30		kernel_neon_end();
31		src += n;
32		srclen -= n;
33	} while (srclen);
34	return 0;
35}
36
37static struct shash_alg nhpoly1305_alg = {
38	.base.cra_name		= "nhpoly1305",
39	.base.cra_driver_name	= "nhpoly1305-neon",
40	.base.cra_priority	= 200,
41	.base.cra_ctxsize	= sizeof(struct nhpoly1305_key),
42	.base.cra_module	= THIS_MODULE,
43	.digestsize		= POLY1305_DIGEST_SIZE,
44	.init			= crypto_nhpoly1305_init,
45	.update			= nhpoly1305_neon_update,
46	.final			= crypto_nhpoly1305_final,
47	.setkey			= crypto_nhpoly1305_setkey,
48	.descsize		= sizeof(struct nhpoly1305_state),
49};
50
51static int __init nhpoly1305_mod_init(void)
52{
53	if (!(elf_hwcap & HWCAP_NEON))
54		return -ENODEV;
55
56	return crypto_register_shash(&nhpoly1305_alg);
57}
58
59static void __exit nhpoly1305_mod_exit(void)
60{
61	crypto_unregister_shash(&nhpoly1305_alg);
62}
63
64module_init(nhpoly1305_mod_init);
65module_exit(nhpoly1305_mod_exit);
66
67MODULE_DESCRIPTION("NHPoly1305 ε-almost-∆-universal hash function (NEON-accelerated)");
68MODULE_LICENSE("GPL v2");
69MODULE_AUTHOR("Eric Biggers <ebiggers@google.com>");
70MODULE_ALIAS_CRYPTO("nhpoly1305");
71MODULE_ALIAS_CRYPTO("nhpoly1305-neon");
72