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
16 asmlinkage void nh_neon(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 */
_nh_neon(const u32 * key,const u8 * message,size_t message_len,__le64 hash[NH_NUM_PASSES])20 static void _nh_neon(const u32 *key, const u8 *message, size_t message_len,
21 __le64 hash[NH_NUM_PASSES])
22 {
23 nh_neon(key, message, message_len, (u8 *)hash);
24 }
25
nhpoly1305_neon_update(struct shash_desc * desc,const u8 * src,unsigned int srclen)26 static int nhpoly1305_neon_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_neon_begin();
36 crypto_nhpoly1305_update_helper(desc, src, n, _nh_neon);
37 kernel_neon_end();
38 src += n;
39 srclen -= n;
40 } while (srclen);
41 return 0;
42 }
43
44 static struct shash_alg nhpoly1305_alg = {
45 .base.cra_name = "nhpoly1305",
46 .base.cra_driver_name = "nhpoly1305-neon",
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_neon_update,
53 .final = crypto_nhpoly1305_final,
54 .setkey = crypto_nhpoly1305_setkey,
55 .descsize = sizeof(struct nhpoly1305_state),
56 };
57
nhpoly1305_mod_init(void)58 static int __init nhpoly1305_mod_init(void)
59 {
60 if (!(elf_hwcap & HWCAP_NEON))
61 return -ENODEV;
62
63 return crypto_register_shash(&nhpoly1305_alg);
64 }
65
nhpoly1305_mod_exit(void)66 static void __exit nhpoly1305_mod_exit(void)
67 {
68 crypto_unregister_shash(&nhpoly1305_alg);
69 }
70
71 module_init(nhpoly1305_mod_init);
72 module_exit(nhpoly1305_mod_exit);
73
74 MODULE_DESCRIPTION("NHPoly1305 ε-almost-∆-universal hash function (NEON-accelerated)");
75 MODULE_LICENSE("GPL v2");
76 MODULE_AUTHOR("Eric Biggers <ebiggers@google.com>");
77 MODULE_ALIAS_CRYPTO("nhpoly1305");
78 MODULE_ALIAS_CRYPTO("nhpoly1305-neon");
79