xref: /linux/arch/x86/crypto/sha256_ssse3_glue.c (revision ca55b2fef3a9373fcfc30f82fd26bc7fccbda732)
1 /*
2  * Cryptographic API.
3  *
4  * Glue code for the SHA256 Secure Hash Algorithm assembler
5  * implementation using supplemental SSE3 / AVX / AVX2 instructions.
6  *
7  * This file is based on sha256_generic.c
8  *
9  * Copyright (C) 2013 Intel Corporation.
10  *
11  * Author:
12  *     Tim Chen <tim.c.chen@linux.intel.com>
13  *
14  * This program is free software; you can redistribute it and/or modify it
15  * under the terms of the GNU General Public License as published by the Free
16  * Software Foundation; either version 2 of the License, or (at your option)
17  * any later version.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
20  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
21  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
22  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
23  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
24  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
25  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
26  * SOFTWARE.
27  */
28 
29 
30 #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
31 
32 #include <crypto/internal/hash.h>
33 #include <linux/init.h>
34 #include <linux/module.h>
35 #include <linux/mm.h>
36 #include <linux/cryptohash.h>
37 #include <linux/types.h>
38 #include <crypto/sha.h>
39 #include <crypto/sha256_base.h>
40 #include <asm/fpu/api.h>
41 #include <linux/string.h>
42 
43 asmlinkage void sha256_transform_ssse3(u32 *digest, const char *data,
44 				       u64 rounds);
45 #ifdef CONFIG_AS_AVX
46 asmlinkage void sha256_transform_avx(u32 *digest, const char *data,
47 				     u64 rounds);
48 #endif
49 #ifdef CONFIG_AS_AVX2
50 asmlinkage void sha256_transform_rorx(u32 *digest, const char *data,
51 				      u64 rounds);
52 #endif
53 
54 static void (*sha256_transform_asm)(u32 *, const char *, u64);
55 
56 static int sha256_ssse3_update(struct shash_desc *desc, const u8 *data,
57 			     unsigned int len)
58 {
59 	struct sha256_state *sctx = shash_desc_ctx(desc);
60 
61 	if (!irq_fpu_usable() ||
62 	    (sctx->count % SHA256_BLOCK_SIZE) + len < SHA256_BLOCK_SIZE)
63 		return crypto_sha256_update(desc, data, len);
64 
65 	/* make sure casting to sha256_block_fn() is safe */
66 	BUILD_BUG_ON(offsetof(struct sha256_state, state) != 0);
67 
68 	kernel_fpu_begin();
69 	sha256_base_do_update(desc, data, len,
70 			      (sha256_block_fn *)sha256_transform_asm);
71 	kernel_fpu_end();
72 
73 	return 0;
74 }
75 
76 static int sha256_ssse3_finup(struct shash_desc *desc, const u8 *data,
77 			      unsigned int len, u8 *out)
78 {
79 	if (!irq_fpu_usable())
80 		return crypto_sha256_finup(desc, data, len, out);
81 
82 	kernel_fpu_begin();
83 	if (len)
84 		sha256_base_do_update(desc, data, len,
85 				      (sha256_block_fn *)sha256_transform_asm);
86 	sha256_base_do_finalize(desc, (sha256_block_fn *)sha256_transform_asm);
87 	kernel_fpu_end();
88 
89 	return sha256_base_finish(desc, out);
90 }
91 
92 /* Add padding and return the message digest. */
93 static int sha256_ssse3_final(struct shash_desc *desc, u8 *out)
94 {
95 	return sha256_ssse3_finup(desc, NULL, 0, out);
96 }
97 
98 static struct shash_alg algs[] = { {
99 	.digestsize	=	SHA256_DIGEST_SIZE,
100 	.init		=	sha256_base_init,
101 	.update		=	sha256_ssse3_update,
102 	.final		=	sha256_ssse3_final,
103 	.finup		=	sha256_ssse3_finup,
104 	.descsize	=	sizeof(struct sha256_state),
105 	.base		=	{
106 		.cra_name	=	"sha256",
107 		.cra_driver_name =	"sha256-ssse3",
108 		.cra_priority	=	150,
109 		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
110 		.cra_blocksize	=	SHA256_BLOCK_SIZE,
111 		.cra_module	=	THIS_MODULE,
112 	}
113 }, {
114 	.digestsize	=	SHA224_DIGEST_SIZE,
115 	.init		=	sha224_base_init,
116 	.update		=	sha256_ssse3_update,
117 	.final		=	sha256_ssse3_final,
118 	.finup		=	sha256_ssse3_finup,
119 	.descsize	=	sizeof(struct sha256_state),
120 	.base		=	{
121 		.cra_name	=	"sha224",
122 		.cra_driver_name =	"sha224-ssse3",
123 		.cra_priority	=	150,
124 		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
125 		.cra_blocksize	=	SHA224_BLOCK_SIZE,
126 		.cra_module	=	THIS_MODULE,
127 	}
128 } };
129 
130 #ifdef CONFIG_AS_AVX
131 static bool __init avx_usable(void)
132 {
133 	if (!cpu_has_xfeatures(XSTATE_SSE | XSTATE_YMM, NULL)) {
134 		if (cpu_has_avx)
135 			pr_info("AVX detected but unusable.\n");
136 		return false;
137 	}
138 
139 	return true;
140 }
141 #endif
142 
143 static int __init sha256_ssse3_mod_init(void)
144 {
145 	/* test for SSSE3 first */
146 	if (cpu_has_ssse3)
147 		sha256_transform_asm = sha256_transform_ssse3;
148 
149 #ifdef CONFIG_AS_AVX
150 	/* allow AVX to override SSSE3, it's a little faster */
151 	if (avx_usable()) {
152 #ifdef CONFIG_AS_AVX2
153 		if (boot_cpu_has(X86_FEATURE_AVX2) && boot_cpu_has(X86_FEATURE_BMI2))
154 			sha256_transform_asm = sha256_transform_rorx;
155 		else
156 #endif
157 			sha256_transform_asm = sha256_transform_avx;
158 	}
159 #endif
160 
161 	if (sha256_transform_asm) {
162 #ifdef CONFIG_AS_AVX
163 		if (sha256_transform_asm == sha256_transform_avx)
164 			pr_info("Using AVX optimized SHA-256 implementation\n");
165 #ifdef CONFIG_AS_AVX2
166 		else if (sha256_transform_asm == sha256_transform_rorx)
167 			pr_info("Using AVX2 optimized SHA-256 implementation\n");
168 #endif
169 		else
170 #endif
171 			pr_info("Using SSSE3 optimized SHA-256 implementation\n");
172 		return crypto_register_shashes(algs, ARRAY_SIZE(algs));
173 	}
174 	pr_info("Neither AVX nor SSSE3 is available/usable.\n");
175 
176 	return -ENODEV;
177 }
178 
179 static void __exit sha256_ssse3_mod_fini(void)
180 {
181 	crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
182 }
183 
184 module_init(sha256_ssse3_mod_init);
185 module_exit(sha256_ssse3_mod_fini);
186 
187 MODULE_LICENSE("GPL");
188 MODULE_DESCRIPTION("SHA256 Secure Hash Algorithm, Supplemental SSE3 accelerated");
189 
190 MODULE_ALIAS_CRYPTO("sha256");
191 MODULE_ALIAS_CRYPTO("sha224");
192