xref: /openbmc/linux/arch/arm64/crypto/sha256-glue.c (revision 6c33a6f4)
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/sha.h>
14 #include <crypto/sha256_base.h>
15 #include <linux/cryptohash.h>
16 #include <linux/types.h>
17 #include <linux/string.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_block_data_order(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_block_neon(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,
49 				     __sha256_block_data_order);
50 }
51 
52 static int crypto_sha256_arm64_finup(struct shash_desc *desc, const u8 *data,
53 				     unsigned int len, u8 *out)
54 {
55 	if (len)
56 		sha256_base_do_update(desc, data, len,
57 				      __sha256_block_data_order);
58 	sha256_base_do_finalize(desc, __sha256_block_data_order);
59 
60 	return sha256_base_finish(desc, out);
61 }
62 
63 static int crypto_sha256_arm64_final(struct shash_desc *desc, u8 *out)
64 {
65 	return crypto_sha256_arm64_finup(desc, NULL, 0, out);
66 }
67 
68 static struct shash_alg algs[] = { {
69 	.digestsize		= SHA256_DIGEST_SIZE,
70 	.init			= sha256_base_init,
71 	.update			= crypto_sha256_arm64_update,
72 	.final			= crypto_sha256_arm64_final,
73 	.finup			= crypto_sha256_arm64_finup,
74 	.descsize		= sizeof(struct sha256_state),
75 	.base.cra_name		= "sha256",
76 	.base.cra_driver_name	= "sha256-arm64",
77 	.base.cra_priority	= 125,
78 	.base.cra_blocksize	= SHA256_BLOCK_SIZE,
79 	.base.cra_module	= THIS_MODULE,
80 }, {
81 	.digestsize		= SHA224_DIGEST_SIZE,
82 	.init			= sha224_base_init,
83 	.update			= crypto_sha256_arm64_update,
84 	.final			= crypto_sha256_arm64_final,
85 	.finup			= crypto_sha256_arm64_finup,
86 	.descsize		= sizeof(struct sha256_state),
87 	.base.cra_name		= "sha224",
88 	.base.cra_driver_name	= "sha224-arm64",
89 	.base.cra_priority	= 125,
90 	.base.cra_blocksize	= SHA224_BLOCK_SIZE,
91 	.base.cra_module	= THIS_MODULE,
92 } };
93 
94 static int sha256_update_neon(struct shash_desc *desc, const u8 *data,
95 			      unsigned int len)
96 {
97 	struct sha256_state *sctx = shash_desc_ctx(desc);
98 
99 	if (!crypto_simd_usable())
100 		return sha256_base_do_update(desc, data, len,
101 				__sha256_block_data_order);
102 
103 	while (len > 0) {
104 		unsigned int chunk = len;
105 
106 		/*
107 		 * Don't hog the CPU for the entire time it takes to process all
108 		 * input when running on a preemptible kernel, but process the
109 		 * data block by block instead.
110 		 */
111 		if (IS_ENABLED(CONFIG_PREEMPTION) &&
112 		    chunk + sctx->count % SHA256_BLOCK_SIZE > SHA256_BLOCK_SIZE)
113 			chunk = SHA256_BLOCK_SIZE -
114 				sctx->count % SHA256_BLOCK_SIZE;
115 
116 		kernel_neon_begin();
117 		sha256_base_do_update(desc, data, chunk, __sha256_block_neon);
118 		kernel_neon_end();
119 		data += chunk;
120 		len -= chunk;
121 	}
122 	return 0;
123 }
124 
125 static int sha256_finup_neon(struct shash_desc *desc, const u8 *data,
126 			     unsigned int len, u8 *out)
127 {
128 	if (!crypto_simd_usable()) {
129 		if (len)
130 			sha256_base_do_update(desc, data, len,
131 				__sha256_block_data_order);
132 		sha256_base_do_finalize(desc, __sha256_block_data_order);
133 	} else {
134 		if (len)
135 			sha256_update_neon(desc, data, len);
136 		kernel_neon_begin();
137 		sha256_base_do_finalize(desc, __sha256_block_neon);
138 		kernel_neon_end();
139 	}
140 	return sha256_base_finish(desc, out);
141 }
142 
143 static int sha256_final_neon(struct shash_desc *desc, u8 *out)
144 {
145 	return sha256_finup_neon(desc, NULL, 0, out);
146 }
147 
148 static struct shash_alg neon_algs[] = { {
149 	.digestsize		= SHA256_DIGEST_SIZE,
150 	.init			= sha256_base_init,
151 	.update			= sha256_update_neon,
152 	.final			= sha256_final_neon,
153 	.finup			= sha256_finup_neon,
154 	.descsize		= sizeof(struct sha256_state),
155 	.base.cra_name		= "sha256",
156 	.base.cra_driver_name	= "sha256-arm64-neon",
157 	.base.cra_priority	= 150,
158 	.base.cra_blocksize	= SHA256_BLOCK_SIZE,
159 	.base.cra_module	= THIS_MODULE,
160 }, {
161 	.digestsize		= SHA224_DIGEST_SIZE,
162 	.init			= sha224_base_init,
163 	.update			= sha256_update_neon,
164 	.final			= sha256_final_neon,
165 	.finup			= sha256_finup_neon,
166 	.descsize		= sizeof(struct sha256_state),
167 	.base.cra_name		= "sha224",
168 	.base.cra_driver_name	= "sha224-arm64-neon",
169 	.base.cra_priority	= 150,
170 	.base.cra_blocksize	= SHA224_BLOCK_SIZE,
171 	.base.cra_module	= THIS_MODULE,
172 } };
173 
174 static int __init sha256_mod_init(void)
175 {
176 	int ret = crypto_register_shashes(algs, ARRAY_SIZE(algs));
177 	if (ret)
178 		return ret;
179 
180 	if (cpu_have_named_feature(ASIMD)) {
181 		ret = crypto_register_shashes(neon_algs, ARRAY_SIZE(neon_algs));
182 		if (ret)
183 			crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
184 	}
185 	return ret;
186 }
187 
188 static void __exit sha256_mod_fini(void)
189 {
190 	if (cpu_have_named_feature(ASIMD))
191 		crypto_unregister_shashes(neon_algs, ARRAY_SIZE(neon_algs));
192 	crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
193 }
194 
195 module_init(sha256_mod_init);
196 module_exit(sha256_mod_fini);
197