xref: /openbmc/linux/arch/arm64/crypto/sha2-ce-glue.c (revision dc6a81c3)
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 static void __sha2_ce_transform(struct sha256_state *sst, u8 const *src,
32 				int blocks)
33 {
34 	sha2_ce_transform(container_of(sst, struct sha256_ce_state, sst), src,
35 			  blocks);
36 }
37 
38 const u32 sha256_ce_offsetof_count = offsetof(struct sha256_ce_state,
39 					      sst.count);
40 const u32 sha256_ce_offsetof_finalize = offsetof(struct sha256_ce_state,
41 						 finalize);
42 
43 asmlinkage void sha256_block_data_order(u32 *digest, u8 const *src, int blocks);
44 
45 static void __sha256_block_data_order(struct sha256_state *sst, u8 const *src,
46 				      int blocks)
47 {
48 	sha256_block_data_order(sst->state, src, blocks);
49 }
50 
51 static int sha256_ce_update(struct shash_desc *desc, const u8 *data,
52 			    unsigned int len)
53 {
54 	struct sha256_ce_state *sctx = shash_desc_ctx(desc);
55 
56 	if (!crypto_simd_usable())
57 		return sha256_base_do_update(desc, data, len,
58 				__sha256_block_data_order);
59 
60 	sctx->finalize = 0;
61 	kernel_neon_begin();
62 	sha256_base_do_update(desc, data, len, __sha2_ce_transform);
63 	kernel_neon_end();
64 
65 	return 0;
66 }
67 
68 static int sha256_ce_finup(struct shash_desc *desc, const u8 *data,
69 			   unsigned int len, u8 *out)
70 {
71 	struct sha256_ce_state *sctx = shash_desc_ctx(desc);
72 	bool finalize = !sctx->sst.count && !(len % SHA256_BLOCK_SIZE) && len;
73 
74 	if (!crypto_simd_usable()) {
75 		if (len)
76 			sha256_base_do_update(desc, data, len,
77 				__sha256_block_data_order);
78 		sha256_base_do_finalize(desc, __sha256_block_data_order);
79 		return sha256_base_finish(desc, out);
80 	}
81 
82 	/*
83 	 * Allow the asm code to perform the finalization if there is no
84 	 * partial data and the input is a round multiple of the block size.
85 	 */
86 	sctx->finalize = finalize;
87 
88 	kernel_neon_begin();
89 	sha256_base_do_update(desc, data, len, __sha2_ce_transform);
90 	if (!finalize)
91 		sha256_base_do_finalize(desc, __sha2_ce_transform);
92 	kernel_neon_end();
93 	return sha256_base_finish(desc, out);
94 }
95 
96 static int sha256_ce_final(struct shash_desc *desc, u8 *out)
97 {
98 	struct sha256_ce_state *sctx = shash_desc_ctx(desc);
99 
100 	if (!crypto_simd_usable()) {
101 		sha256_base_do_finalize(desc, __sha256_block_data_order);
102 		return sha256_base_finish(desc, out);
103 	}
104 
105 	sctx->finalize = 0;
106 	kernel_neon_begin();
107 	sha256_base_do_finalize(desc, __sha2_ce_transform);
108 	kernel_neon_end();
109 	return sha256_base_finish(desc, out);
110 }
111 
112 static struct shash_alg algs[] = { {
113 	.init			= sha224_base_init,
114 	.update			= sha256_ce_update,
115 	.final			= sha256_ce_final,
116 	.finup			= sha256_ce_finup,
117 	.descsize		= sizeof(struct sha256_ce_state),
118 	.digestsize		= SHA224_DIGEST_SIZE,
119 	.base			= {
120 		.cra_name		= "sha224",
121 		.cra_driver_name	= "sha224-ce",
122 		.cra_priority		= 200,
123 		.cra_blocksize		= SHA256_BLOCK_SIZE,
124 		.cra_module		= THIS_MODULE,
125 	}
126 }, {
127 	.init			= sha256_base_init,
128 	.update			= sha256_ce_update,
129 	.final			= sha256_ce_final,
130 	.finup			= sha256_ce_finup,
131 	.descsize		= sizeof(struct sha256_ce_state),
132 	.digestsize		= SHA256_DIGEST_SIZE,
133 	.base			= {
134 		.cra_name		= "sha256",
135 		.cra_driver_name	= "sha256-ce",
136 		.cra_priority		= 200,
137 		.cra_blocksize		= SHA256_BLOCK_SIZE,
138 		.cra_module		= THIS_MODULE,
139 	}
140 } };
141 
142 static int __init sha2_ce_mod_init(void)
143 {
144 	return crypto_register_shashes(algs, ARRAY_SIZE(algs));
145 }
146 
147 static void __exit sha2_ce_mod_fini(void)
148 {
149 	crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
150 }
151 
152 module_cpu_feature_match(SHA2, sha2_ce_mod_init);
153 module_exit(sha2_ce_mod_fini);
154