xref: /linux/arch/arm64/crypto/sha256-glue.c (revision 3d0fe49454652117522f60bfbefb978ba0e5300b)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Linux/arm64 port of the OpenSSL SHA256 implementation for AArch64
4  *
5  * Copyright (c) 2016 Linaro Ltd. <ard.biesheuvel@linaro.org>
6  */
7 
8 #include <asm/hwcap.h>
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/sha2.h>
14 #include <crypto/sha256_base.h>
15 #include <linux/module.h>
16 #include <linux/string.h>
17 #include <linux/types.h>
18 
19 MODULE_DESCRIPTION("SHA-224/SHA-256 secure hash for arm64");
20 MODULE_AUTHOR("Andy Polyakov <appro@openssl.org>");
21 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
22 MODULE_LICENSE("GPL v2");
23 MODULE_ALIAS_CRYPTO("sha224");
24 MODULE_ALIAS_CRYPTO("sha256");
25 
26 asmlinkage void sha256_block_data_order(u32 *digest, const void *data,
27 					unsigned int num_blks);
28 EXPORT_SYMBOL(sha256_block_data_order);
29 
30 static void sha256_arm64_transform(struct sha256_state *sst, u8 const *src,
31 				   int blocks)
32 {
33 	sha256_block_data_order(sst->state, src, blocks);
34 }
35 
36 asmlinkage void sha256_block_neon(u32 *digest, const void *data,
37 				  unsigned int num_blks);
38 
39 static void sha256_neon_transform(struct sha256_state *sst, u8 const *src,
40 				  int blocks)
41 {
42 	sha256_block_neon(sst->state, src, blocks);
43 }
44 
45 static int crypto_sha256_arm64_update(struct shash_desc *desc, const u8 *data,
46 				      unsigned int len)
47 {
48 	return sha256_base_do_update(desc, data, len, sha256_arm64_transform);
49 }
50 
51 static int crypto_sha256_arm64_finup(struct shash_desc *desc, const u8 *data,
52 				     unsigned int len, u8 *out)
53 {
54 	if (len)
55 		sha256_base_do_update(desc, data, len, sha256_arm64_transform);
56 	sha256_base_do_finalize(desc, sha256_arm64_transform);
57 
58 	return sha256_base_finish(desc, out);
59 }
60 
61 static int crypto_sha256_arm64_final(struct shash_desc *desc, u8 *out)
62 {
63 	return crypto_sha256_arm64_finup(desc, NULL, 0, out);
64 }
65 
66 static struct shash_alg algs[] = { {
67 	.digestsize		= SHA256_DIGEST_SIZE,
68 	.init			= sha256_base_init,
69 	.update			= crypto_sha256_arm64_update,
70 	.final			= crypto_sha256_arm64_final,
71 	.finup			= crypto_sha256_arm64_finup,
72 	.descsize		= sizeof(struct sha256_state),
73 	.base.cra_name		= "sha256",
74 	.base.cra_driver_name	= "sha256-arm64",
75 	.base.cra_priority	= 125,
76 	.base.cra_blocksize	= SHA256_BLOCK_SIZE,
77 	.base.cra_module	= THIS_MODULE,
78 }, {
79 	.digestsize		= SHA224_DIGEST_SIZE,
80 	.init			= sha224_base_init,
81 	.update			= crypto_sha256_arm64_update,
82 	.final			= crypto_sha256_arm64_final,
83 	.finup			= crypto_sha256_arm64_finup,
84 	.descsize		= sizeof(struct sha256_state),
85 	.base.cra_name		= "sha224",
86 	.base.cra_driver_name	= "sha224-arm64",
87 	.base.cra_priority	= 125,
88 	.base.cra_blocksize	= SHA224_BLOCK_SIZE,
89 	.base.cra_module	= THIS_MODULE,
90 } };
91 
92 static int sha256_update_neon(struct shash_desc *desc, const u8 *data,
93 			      unsigned int len)
94 {
95 	struct sha256_state *sctx = shash_desc_ctx(desc);
96 
97 	if (!crypto_simd_usable())
98 		return sha256_base_do_update(desc, data, len,
99 				sha256_arm64_transform);
100 
101 	while (len > 0) {
102 		unsigned int chunk = len;
103 
104 		/*
105 		 * Don't hog the CPU for the entire time it takes to process all
106 		 * input when running on a preemptible kernel, but process the
107 		 * data block by block instead.
108 		 */
109 		if (IS_ENABLED(CONFIG_PREEMPTION) &&
110 		    chunk + sctx->count % SHA256_BLOCK_SIZE > SHA256_BLOCK_SIZE)
111 			chunk = SHA256_BLOCK_SIZE -
112 				sctx->count % SHA256_BLOCK_SIZE;
113 
114 		kernel_neon_begin();
115 		sha256_base_do_update(desc, data, chunk, sha256_neon_transform);
116 		kernel_neon_end();
117 		data += chunk;
118 		len -= chunk;
119 	}
120 	return 0;
121 }
122 
123 static int sha256_finup_neon(struct shash_desc *desc, const u8 *data,
124 			     unsigned int len, u8 *out)
125 {
126 	if (!crypto_simd_usable()) {
127 		if (len)
128 			sha256_base_do_update(desc, data, len,
129 				sha256_arm64_transform);
130 		sha256_base_do_finalize(desc, sha256_arm64_transform);
131 	} else {
132 		if (len)
133 			sha256_update_neon(desc, data, len);
134 		kernel_neon_begin();
135 		sha256_base_do_finalize(desc, sha256_neon_transform);
136 		kernel_neon_end();
137 	}
138 	return sha256_base_finish(desc, out);
139 }
140 
141 static int sha256_final_neon(struct shash_desc *desc, u8 *out)
142 {
143 	return sha256_finup_neon(desc, NULL, 0, out);
144 }
145 
146 static struct shash_alg neon_algs[] = { {
147 	.digestsize		= SHA256_DIGEST_SIZE,
148 	.init			= sha256_base_init,
149 	.update			= sha256_update_neon,
150 	.final			= sha256_final_neon,
151 	.finup			= sha256_finup_neon,
152 	.descsize		= sizeof(struct sha256_state),
153 	.base.cra_name		= "sha256",
154 	.base.cra_driver_name	= "sha256-arm64-neon",
155 	.base.cra_priority	= 150,
156 	.base.cra_blocksize	= SHA256_BLOCK_SIZE,
157 	.base.cra_module	= THIS_MODULE,
158 }, {
159 	.digestsize		= SHA224_DIGEST_SIZE,
160 	.init			= sha224_base_init,
161 	.update			= sha256_update_neon,
162 	.final			= sha256_final_neon,
163 	.finup			= sha256_finup_neon,
164 	.descsize		= sizeof(struct sha256_state),
165 	.base.cra_name		= "sha224",
166 	.base.cra_driver_name	= "sha224-arm64-neon",
167 	.base.cra_priority	= 150,
168 	.base.cra_blocksize	= SHA224_BLOCK_SIZE,
169 	.base.cra_module	= THIS_MODULE,
170 } };
171 
172 static int __init sha256_mod_init(void)
173 {
174 	int ret = crypto_register_shashes(algs, ARRAY_SIZE(algs));
175 	if (ret)
176 		return ret;
177 
178 	if (cpu_have_named_feature(ASIMD)) {
179 		ret = crypto_register_shashes(neon_algs, ARRAY_SIZE(neon_algs));
180 		if (ret)
181 			crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
182 	}
183 	return ret;
184 }
185 
186 static void __exit sha256_mod_fini(void)
187 {
188 	if (cpu_have_named_feature(ASIMD))
189 		crypto_unregister_shashes(neon_algs, ARRAY_SIZE(neon_algs));
190 	crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
191 }
192 
193 module_init(sha256_mod_init);
194 module_exit(sha256_mod_fini);
195