1/*
2 * sha2-ce-glue.c - SHA-224/SHA-256 using ARMv8 Crypto Extensions
3 *
4 * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org>
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 as
8 * published by the Free Software Foundation.
9 */
10
11#include <crypto/internal/hash.h>
12#include <crypto/sha.h>
13#include <crypto/sha256_base.h>
14#include <linux/crypto.h>
15#include <linux/module.h>
16
17#include <asm/hwcap.h>
18#include <asm/simd.h>
19#include <asm/neon.h>
20#include <asm/unaligned.h>
21
22#include "sha256_glue.h"
23
24MODULE_DESCRIPTION("SHA-224/SHA-256 secure hash using ARMv8 Crypto Extensions");
25MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
26MODULE_LICENSE("GPL v2");
27
28asmlinkage void sha2_ce_transform(struct sha256_state *sst, u8 const *src,
29				  int blocks);
30
31static int sha2_ce_update(struct shash_desc *desc, const u8 *data,
32			  unsigned int len)
33{
34	struct sha256_state *sctx = shash_desc_ctx(desc);
35
36	if (!may_use_simd() ||
37	    (sctx->count % SHA256_BLOCK_SIZE) + len < SHA256_BLOCK_SIZE)
38		return crypto_sha256_arm_update(desc, data, len);
39
40	kernel_neon_begin();
41	sha256_base_do_update(desc, data, len,
42			      (sha256_block_fn *)sha2_ce_transform);
43	kernel_neon_end();
44
45	return 0;
46}
47
48static int sha2_ce_finup(struct shash_desc *desc, const u8 *data,
49			 unsigned int len, u8 *out)
50{
51	if (!may_use_simd())
52		return crypto_sha256_arm_finup(desc, data, len, out);
53
54	kernel_neon_begin();
55	if (len)
56		sha256_base_do_update(desc, data, len,
57				      (sha256_block_fn *)sha2_ce_transform);
58	sha256_base_do_finalize(desc, (sha256_block_fn *)sha2_ce_transform);
59	kernel_neon_end();
60
61	return sha256_base_finish(desc, out);
62}
63
64static int sha2_ce_final(struct shash_desc *desc, u8 *out)
65{
66	return sha2_ce_finup(desc, NULL, 0, out);
67}
68
69static struct shash_alg algs[] = { {
70	.init			= sha224_base_init,
71	.update			= sha2_ce_update,
72	.final			= sha2_ce_final,
73	.finup			= sha2_ce_finup,
74	.descsize		= sizeof(struct sha256_state),
75	.digestsize		= SHA224_DIGEST_SIZE,
76	.base			= {
77		.cra_name		= "sha224",
78		.cra_driver_name	= "sha224-ce",
79		.cra_priority		= 300,
80		.cra_flags		= CRYPTO_ALG_TYPE_SHASH,
81		.cra_blocksize		= SHA256_BLOCK_SIZE,
82		.cra_module		= THIS_MODULE,
83	}
84}, {
85	.init			= sha256_base_init,
86	.update			= sha2_ce_update,
87	.final			= sha2_ce_final,
88	.finup			= sha2_ce_finup,
89	.descsize		= sizeof(struct sha256_state),
90	.digestsize		= SHA256_DIGEST_SIZE,
91	.base			= {
92		.cra_name		= "sha256",
93		.cra_driver_name	= "sha256-ce",
94		.cra_priority		= 300,
95		.cra_flags		= CRYPTO_ALG_TYPE_SHASH,
96		.cra_blocksize		= SHA256_BLOCK_SIZE,
97		.cra_module		= THIS_MODULE,
98	}
99} };
100
101static int __init sha2_ce_mod_init(void)
102{
103	if (!(elf_hwcap2 & HWCAP2_SHA2))
104		return -ENODEV;
105	return crypto_register_shashes(algs, ARRAY_SIZE(algs));
106}
107
108static void __exit sha2_ce_mod_fini(void)
109{
110	crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
111}
112
113module_init(sha2_ce_mod_init);
114module_exit(sha2_ce_mod_fini);
115