xref: /openbmc/linux/arch/arm64/crypto/sha256-glue.c (revision 3213486f)
1 /*
2  * Linux/arm64 port of the OpenSSL SHA256 implementation for AArch64
3  *
4  * Copyright (c) 2016 Linaro Ltd. <ard.biesheuvel@linaro.org>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the Free
8  * Software Foundation; either version 2 of the License, or (at your option)
9  * any later version.
10  *
11  */
12 
13 #include <asm/hwcap.h>
14 #include <asm/neon.h>
15 #include <asm/simd.h>
16 #include <crypto/internal/hash.h>
17 #include <crypto/sha.h>
18 #include <crypto/sha256_base.h>
19 #include <linux/cryptohash.h>
20 #include <linux/types.h>
21 #include <linux/string.h>
22 
23 MODULE_DESCRIPTION("SHA-224/SHA-256 secure hash for arm64");
24 MODULE_AUTHOR("Andy Polyakov <appro@openssl.org>");
25 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
26 MODULE_LICENSE("GPL v2");
27 MODULE_ALIAS_CRYPTO("sha224");
28 MODULE_ALIAS_CRYPTO("sha256");
29 
30 asmlinkage void sha256_block_data_order(u32 *digest, const void *data,
31 					unsigned int num_blks);
32 EXPORT_SYMBOL(sha256_block_data_order);
33 
34 asmlinkage void sha256_block_neon(u32 *digest, const void *data,
35 				  unsigned int num_blks);
36 
37 static int sha256_update(struct shash_desc *desc, const u8 *data,
38 			 unsigned int len)
39 {
40 	return sha256_base_do_update(desc, data, len,
41 				(sha256_block_fn *)sha256_block_data_order);
42 }
43 
44 static int sha256_finup(struct shash_desc *desc, const u8 *data,
45 			unsigned int len, u8 *out)
46 {
47 	if (len)
48 		sha256_base_do_update(desc, data, len,
49 				(sha256_block_fn *)sha256_block_data_order);
50 	sha256_base_do_finalize(desc,
51 				(sha256_block_fn *)sha256_block_data_order);
52 
53 	return sha256_base_finish(desc, out);
54 }
55 
56 static int sha256_final(struct shash_desc *desc, u8 *out)
57 {
58 	return sha256_finup(desc, NULL, 0, out);
59 }
60 
61 static struct shash_alg algs[] = { {
62 	.digestsize		= SHA256_DIGEST_SIZE,
63 	.init			= sha256_base_init,
64 	.update			= sha256_update,
65 	.final			= sha256_final,
66 	.finup			= sha256_finup,
67 	.descsize		= sizeof(struct sha256_state),
68 	.base.cra_name		= "sha256",
69 	.base.cra_driver_name	= "sha256-arm64",
70 	.base.cra_priority	= 125,
71 	.base.cra_blocksize	= SHA256_BLOCK_SIZE,
72 	.base.cra_module	= THIS_MODULE,
73 }, {
74 	.digestsize		= SHA224_DIGEST_SIZE,
75 	.init			= sha224_base_init,
76 	.update			= sha256_update,
77 	.final			= sha256_final,
78 	.finup			= sha256_finup,
79 	.descsize		= sizeof(struct sha256_state),
80 	.base.cra_name		= "sha224",
81 	.base.cra_driver_name	= "sha224-arm64",
82 	.base.cra_priority	= 125,
83 	.base.cra_blocksize	= SHA224_BLOCK_SIZE,
84 	.base.cra_module	= THIS_MODULE,
85 } };
86 
87 static int sha256_update_neon(struct shash_desc *desc, const u8 *data,
88 			      unsigned int len)
89 {
90 	struct sha256_state *sctx = shash_desc_ctx(desc);
91 
92 	if (!may_use_simd())
93 		return sha256_base_do_update(desc, data, len,
94 				(sha256_block_fn *)sha256_block_data_order);
95 
96 	while (len > 0) {
97 		unsigned int chunk = len;
98 
99 		/*
100 		 * Don't hog the CPU for the entire time it takes to process all
101 		 * input when running on a preemptible kernel, but process the
102 		 * data block by block instead.
103 		 */
104 		if (IS_ENABLED(CONFIG_PREEMPT) &&
105 		    chunk + sctx->count % SHA256_BLOCK_SIZE > SHA256_BLOCK_SIZE)
106 			chunk = SHA256_BLOCK_SIZE -
107 				sctx->count % SHA256_BLOCK_SIZE;
108 
109 		kernel_neon_begin();
110 		sha256_base_do_update(desc, data, chunk,
111 				      (sha256_block_fn *)sha256_block_neon);
112 		kernel_neon_end();
113 		data += chunk;
114 		len -= chunk;
115 	}
116 	return 0;
117 }
118 
119 static int sha256_finup_neon(struct shash_desc *desc, const u8 *data,
120 			     unsigned int len, u8 *out)
121 {
122 	if (!may_use_simd()) {
123 		if (len)
124 			sha256_base_do_update(desc, data, len,
125 				(sha256_block_fn *)sha256_block_data_order);
126 		sha256_base_do_finalize(desc,
127 				(sha256_block_fn *)sha256_block_data_order);
128 	} else {
129 		if (len)
130 			sha256_update_neon(desc, data, len);
131 		kernel_neon_begin();
132 		sha256_base_do_finalize(desc,
133 				(sha256_block_fn *)sha256_block_neon);
134 		kernel_neon_end();
135 	}
136 	return sha256_base_finish(desc, out);
137 }
138 
139 static int sha256_final_neon(struct shash_desc *desc, u8 *out)
140 {
141 	return sha256_finup_neon(desc, NULL, 0, out);
142 }
143 
144 static struct shash_alg neon_algs[] = { {
145 	.digestsize		= SHA256_DIGEST_SIZE,
146 	.init			= sha256_base_init,
147 	.update			= sha256_update_neon,
148 	.final			= sha256_final_neon,
149 	.finup			= sha256_finup_neon,
150 	.descsize		= sizeof(struct sha256_state),
151 	.base.cra_name		= "sha256",
152 	.base.cra_driver_name	= "sha256-arm64-neon",
153 	.base.cra_priority	= 150,
154 	.base.cra_blocksize	= SHA256_BLOCK_SIZE,
155 	.base.cra_module	= THIS_MODULE,
156 }, {
157 	.digestsize		= SHA224_DIGEST_SIZE,
158 	.init			= sha224_base_init,
159 	.update			= sha256_update_neon,
160 	.final			= sha256_final_neon,
161 	.finup			= sha256_finup_neon,
162 	.descsize		= sizeof(struct sha256_state),
163 	.base.cra_name		= "sha224",
164 	.base.cra_driver_name	= "sha224-arm64-neon",
165 	.base.cra_priority	= 150,
166 	.base.cra_blocksize	= SHA224_BLOCK_SIZE,
167 	.base.cra_module	= THIS_MODULE,
168 } };
169 
170 static int __init sha256_mod_init(void)
171 {
172 	int ret = crypto_register_shashes(algs, ARRAY_SIZE(algs));
173 	if (ret)
174 		return ret;
175 
176 	if (elf_hwcap & HWCAP_ASIMD) {
177 		ret = crypto_register_shashes(neon_algs, ARRAY_SIZE(neon_algs));
178 		if (ret)
179 			crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
180 	}
181 	return ret;
182 }
183 
184 static void __exit sha256_mod_fini(void)
185 {
186 	if (elf_hwcap & HWCAP_ASIMD)
187 		crypto_unregister_shashes(neon_algs, ARRAY_SIZE(neon_algs));
188 	crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
189 }
190 
191 module_init(sha256_mod_init);
192 module_exit(sha256_mod_fini);
193