xref: /openbmc/linux/arch/arm64/crypto/sha2-ce-glue.c (revision 7ce2e76a)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * sha2-ce-glue.c - SHA-224/SHA-256 using ARMv8 Crypto Extensions
4  *
5  * Copyright (C) 2014 - 2017 Linaro Ltd <ard.biesheuvel@linaro.org>
6  */
7 
8 #include <asm/neon.h>
9 #include <asm/simd.h>
10 #include <asm/unaligned.h>
11 #include <crypto/internal/hash.h>
12 #include <crypto/internal/simd.h>
13 #include <crypto/sha.h>
14 #include <crypto/sha256_base.h>
15 #include <linux/cpufeature.h>
16 #include <linux/crypto.h>
17 #include <linux/module.h>
18 
19 MODULE_DESCRIPTION("SHA-224/SHA-256 secure hash using ARMv8 Crypto Extensions");
20 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
21 MODULE_LICENSE("GPL v2");
22 
23 struct sha256_ce_state {
24 	struct sha256_state	sst;
25 	u32			finalize;
26 };
27 
28 asmlinkage void sha2_ce_transform(struct sha256_ce_state *sst, u8 const *src,
29 				  int blocks);
30 
31 const u32 sha256_ce_offsetof_count = offsetof(struct sha256_ce_state,
32 					      sst.count);
33 const u32 sha256_ce_offsetof_finalize = offsetof(struct sha256_ce_state,
34 						 finalize);
35 
36 asmlinkage void sha256_block_data_order(u32 *digest, u8 const *src, int blocks);
37 
38 static int sha256_ce_update(struct shash_desc *desc, const u8 *data,
39 			    unsigned int len)
40 {
41 	struct sha256_ce_state *sctx = shash_desc_ctx(desc);
42 
43 	if (!crypto_simd_usable())
44 		return sha256_base_do_update(desc, data, len,
45 				(sha256_block_fn *)sha256_block_data_order);
46 
47 	sctx->finalize = 0;
48 	kernel_neon_begin();
49 	sha256_base_do_update(desc, data, len,
50 			      (sha256_block_fn *)sha2_ce_transform);
51 	kernel_neon_end();
52 
53 	return 0;
54 }
55 
56 static int sha256_ce_finup(struct shash_desc *desc, const u8 *data,
57 			   unsigned int len, u8 *out)
58 {
59 	struct sha256_ce_state *sctx = shash_desc_ctx(desc);
60 	bool finalize = !sctx->sst.count && !(len % SHA256_BLOCK_SIZE) && len;
61 
62 	if (!crypto_simd_usable()) {
63 		if (len)
64 			sha256_base_do_update(desc, data, len,
65 				(sha256_block_fn *)sha256_block_data_order);
66 		sha256_base_do_finalize(desc,
67 				(sha256_block_fn *)sha256_block_data_order);
68 		return sha256_base_finish(desc, out);
69 	}
70 
71 	/*
72 	 * Allow the asm code to perform the finalization if there is no
73 	 * partial data and the input is a round multiple of the block size.
74 	 */
75 	sctx->finalize = finalize;
76 
77 	kernel_neon_begin();
78 	sha256_base_do_update(desc, data, len,
79 			      (sha256_block_fn *)sha2_ce_transform);
80 	if (!finalize)
81 		sha256_base_do_finalize(desc,
82 					(sha256_block_fn *)sha2_ce_transform);
83 	kernel_neon_end();
84 	return sha256_base_finish(desc, out);
85 }
86 
87 static int sha256_ce_final(struct shash_desc *desc, u8 *out)
88 {
89 	struct sha256_ce_state *sctx = shash_desc_ctx(desc);
90 
91 	if (!crypto_simd_usable()) {
92 		sha256_base_do_finalize(desc,
93 				(sha256_block_fn *)sha256_block_data_order);
94 		return sha256_base_finish(desc, out);
95 	}
96 
97 	sctx->finalize = 0;
98 	kernel_neon_begin();
99 	sha256_base_do_finalize(desc, (sha256_block_fn *)sha2_ce_transform);
100 	kernel_neon_end();
101 	return sha256_base_finish(desc, out);
102 }
103 
104 static struct shash_alg algs[] = { {
105 	.init			= sha224_base_init,
106 	.update			= sha256_ce_update,
107 	.final			= sha256_ce_final,
108 	.finup			= sha256_ce_finup,
109 	.descsize		= sizeof(struct sha256_ce_state),
110 	.digestsize		= SHA224_DIGEST_SIZE,
111 	.base			= {
112 		.cra_name		= "sha224",
113 		.cra_driver_name	= "sha224-ce",
114 		.cra_priority		= 200,
115 		.cra_blocksize		= SHA256_BLOCK_SIZE,
116 		.cra_module		= THIS_MODULE,
117 	}
118 }, {
119 	.init			= sha256_base_init,
120 	.update			= sha256_ce_update,
121 	.final			= sha256_ce_final,
122 	.finup			= sha256_ce_finup,
123 	.descsize		= sizeof(struct sha256_ce_state),
124 	.digestsize		= SHA256_DIGEST_SIZE,
125 	.base			= {
126 		.cra_name		= "sha256",
127 		.cra_driver_name	= "sha256-ce",
128 		.cra_priority		= 200,
129 		.cra_blocksize		= SHA256_BLOCK_SIZE,
130 		.cra_module		= THIS_MODULE,
131 	}
132 } };
133 
134 static int __init sha2_ce_mod_init(void)
135 {
136 	return crypto_register_shashes(algs, ARRAY_SIZE(algs));
137 }
138 
139 static void __exit sha2_ce_mod_fini(void)
140 {
141 	crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
142 }
143 
144 module_cpu_feature_match(SHA2, sha2_ce_mod_init);
145 module_exit(sha2_ce_mod_fini);
146