xref: /openbmc/linux/arch/arm/crypto/sha2-ce-glue.c (revision 8730046c)
1 /*
2  * sha2-ce-glue.c - SHA-224/SHA-256 using ARMv8 Crypto Extensions
3  *
4  * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 as
8  * published by the Free Software Foundation.
9  */
10 
11 #include <crypto/internal/hash.h>
12 #include <crypto/sha.h>
13 #include <crypto/sha256_base.h>
14 #include <linux/crypto.h>
15 #include <linux/module.h>
16 
17 #include <asm/hwcap.h>
18 #include <asm/simd.h>
19 #include <asm/neon.h>
20 #include <asm/unaligned.h>
21 
22 #include "sha256_glue.h"
23 
24 MODULE_DESCRIPTION("SHA-224/SHA-256 secure hash using ARMv8 Crypto Extensions");
25 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
26 MODULE_LICENSE("GPL v2");
27 
28 asmlinkage void sha2_ce_transform(struct sha256_state *sst, u8 const *src,
29 				  int blocks);
30 
31 static int sha2_ce_update(struct shash_desc *desc, const u8 *data,
32 			  unsigned int len)
33 {
34 	struct sha256_state *sctx = shash_desc_ctx(desc);
35 
36 	if (!may_use_simd() ||
37 	    (sctx->count % SHA256_BLOCK_SIZE) + len < SHA256_BLOCK_SIZE)
38 		return crypto_sha256_arm_update(desc, data, len);
39 
40 	kernel_neon_begin();
41 	sha256_base_do_update(desc, data, len,
42 			      (sha256_block_fn *)sha2_ce_transform);
43 	kernel_neon_end();
44 
45 	return 0;
46 }
47 
48 static int sha2_ce_finup(struct shash_desc *desc, const u8 *data,
49 			 unsigned int len, u8 *out)
50 {
51 	if (!may_use_simd())
52 		return crypto_sha256_arm_finup(desc, data, len, out);
53 
54 	kernel_neon_begin();
55 	if (len)
56 		sha256_base_do_update(desc, data, len,
57 				      (sha256_block_fn *)sha2_ce_transform);
58 	sha256_base_do_finalize(desc, (sha256_block_fn *)sha2_ce_transform);
59 	kernel_neon_end();
60 
61 	return sha256_base_finish(desc, out);
62 }
63 
64 static int sha2_ce_final(struct shash_desc *desc, u8 *out)
65 {
66 	return sha2_ce_finup(desc, NULL, 0, out);
67 }
68 
69 static struct shash_alg algs[] = { {
70 	.init			= sha224_base_init,
71 	.update			= sha2_ce_update,
72 	.final			= sha2_ce_final,
73 	.finup			= sha2_ce_finup,
74 	.descsize		= sizeof(struct sha256_state),
75 	.digestsize		= SHA224_DIGEST_SIZE,
76 	.base			= {
77 		.cra_name		= "sha224",
78 		.cra_driver_name	= "sha224-ce",
79 		.cra_priority		= 300,
80 		.cra_flags		= CRYPTO_ALG_TYPE_SHASH,
81 		.cra_blocksize		= SHA256_BLOCK_SIZE,
82 		.cra_module		= THIS_MODULE,
83 	}
84 }, {
85 	.init			= sha256_base_init,
86 	.update			= sha2_ce_update,
87 	.final			= sha2_ce_final,
88 	.finup			= sha2_ce_finup,
89 	.descsize		= sizeof(struct sha256_state),
90 	.digestsize		= SHA256_DIGEST_SIZE,
91 	.base			= {
92 		.cra_name		= "sha256",
93 		.cra_driver_name	= "sha256-ce",
94 		.cra_priority		= 300,
95 		.cra_flags		= CRYPTO_ALG_TYPE_SHASH,
96 		.cra_blocksize		= SHA256_BLOCK_SIZE,
97 		.cra_module		= THIS_MODULE,
98 	}
99 } };
100 
101 static int __init sha2_ce_mod_init(void)
102 {
103 	if (!(elf_hwcap2 & HWCAP2_SHA2))
104 		return -ENODEV;
105 	return crypto_register_shashes(algs, ARRAY_SIZE(algs));
106 }
107 
108 static void __exit sha2_ce_mod_fini(void)
109 {
110 	crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
111 }
112 
113 module_init(sha2_ce_mod_init);
114 module_exit(sha2_ce_mod_fini);
115