1// SPDX-License-Identifier: GPL-2.0
2/*
3 * NHPoly1305 - ε-almost-∆-universal hash function for Adiantum
4 * (SSE2 accelerated version)
5 *
6 * Copyright 2018 Google LLC
7 */
8
9#include <crypto/internal/hash.h>
10#include <crypto/internal/simd.h>
11#include <crypto/nhpoly1305.h>
12#include <linux/module.h>
13#include <linux/sizes.h>
14#include <asm/simd.h>
15
16asmlinkage void nh_sse2(const u32 *key, const u8 *message, size_t message_len,
17			u8 hash[NH_HASH_BYTES]);
18
19/* wrapper to avoid indirect call to assembly, which doesn't work with CFI */
20static void _nh_sse2(const u32 *key, const u8 *message, size_t message_len,
21		     __le64 hash[NH_NUM_PASSES])
22{
23	nh_sse2(key, message, message_len, (u8 *)hash);
24}
25
26static int nhpoly1305_sse2_update(struct shash_desc *desc,
27				  const u8 *src, unsigned int srclen)
28{
29	if (srclen < 64 || !crypto_simd_usable())
30		return crypto_nhpoly1305_update(desc, src, srclen);
31
32	do {
33		unsigned int n = min_t(unsigned int, srclen, SZ_4K);
34
35		kernel_fpu_begin();
36		crypto_nhpoly1305_update_helper(desc, src, n, _nh_sse2);
37		kernel_fpu_end();
38		src += n;
39		srclen -= n;
40	} while (srclen);
41	return 0;
42}
43
44static struct shash_alg nhpoly1305_alg = {
45	.base.cra_name		= "nhpoly1305",
46	.base.cra_driver_name	= "nhpoly1305-sse2",
47	.base.cra_priority	= 200,
48	.base.cra_ctxsize	= sizeof(struct nhpoly1305_key),
49	.base.cra_module	= THIS_MODULE,
50	.digestsize		= POLY1305_DIGEST_SIZE,
51	.init			= crypto_nhpoly1305_init,
52	.update			= nhpoly1305_sse2_update,
53	.final			= crypto_nhpoly1305_final,
54	.setkey			= crypto_nhpoly1305_setkey,
55	.descsize		= sizeof(struct nhpoly1305_state),
56};
57
58static int __init nhpoly1305_mod_init(void)
59{
60	if (!boot_cpu_has(X86_FEATURE_XMM2))
61		return -ENODEV;
62
63	return crypto_register_shash(&nhpoly1305_alg);
64}
65
66static void __exit nhpoly1305_mod_exit(void)
67{
68	crypto_unregister_shash(&nhpoly1305_alg);
69}
70
71module_init(nhpoly1305_mod_init);
72module_exit(nhpoly1305_mod_exit);
73
74MODULE_DESCRIPTION("NHPoly1305 ε-almost-∆-universal hash function (SSE2-accelerated)");
75MODULE_LICENSE("GPL v2");
76MODULE_AUTHOR("Eric Biggers <ebiggers@google.com>");
77MODULE_ALIAS_CRYPTO("nhpoly1305");
78MODULE_ALIAS_CRYPTO("nhpoly1305-sse2");
79