1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * NHPoly1305 - ε-almost-∆-universal hash function for Adiantum
4  * (AVX2 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 
16 asmlinkage void nh_avx2(const u32 *key, const u8 *message, size_t message_len,
17 			__le64 hash[NH_NUM_PASSES]);
18 
nhpoly1305_avx2_update(struct shash_desc * desc,const u8 * src,unsigned int srclen)19 static int nhpoly1305_avx2_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_fpu_begin();
29 		crypto_nhpoly1305_update_helper(desc, src, n, nh_avx2);
30 		kernel_fpu_end();
31 		src += n;
32 		srclen -= n;
33 	} while (srclen);
34 	return 0;
35 }
36 
37 static struct shash_alg nhpoly1305_alg = {
38 	.base.cra_name		= "nhpoly1305",
39 	.base.cra_driver_name	= "nhpoly1305-avx2",
40 	.base.cra_priority	= 300,
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_avx2_update,
46 	.final			= crypto_nhpoly1305_final,
47 	.setkey			= crypto_nhpoly1305_setkey,
48 	.descsize		= sizeof(struct nhpoly1305_state),
49 };
50 
nhpoly1305_mod_init(void)51 static int __init nhpoly1305_mod_init(void)
52 {
53 	if (!boot_cpu_has(X86_FEATURE_AVX2) ||
54 	    !boot_cpu_has(X86_FEATURE_OSXSAVE))
55 		return -ENODEV;
56 
57 	return crypto_register_shash(&nhpoly1305_alg);
58 }
59 
nhpoly1305_mod_exit(void)60 static void __exit nhpoly1305_mod_exit(void)
61 {
62 	crypto_unregister_shash(&nhpoly1305_alg);
63 }
64 
65 module_init(nhpoly1305_mod_init);
66 module_exit(nhpoly1305_mod_exit);
67 
68 MODULE_DESCRIPTION("NHPoly1305 ε-almost-∆-universal hash function (AVX2-accelerated)");
69 MODULE_LICENSE("GPL v2");
70 MODULE_AUTHOR("Eric Biggers <ebiggers@google.com>");
71 MODULE_ALIAS_CRYPTO("nhpoly1305");
72 MODULE_ALIAS_CRYPTO("nhpoly1305-avx2");
73