xref: /openbmc/linux/arch/arm64/crypto/sha1-ce-glue.c (revision f3539c12)
1 /*
2  * sha1-ce-glue.c - SHA-1 secure hash using ARMv8 Crypto Extensions
3  *
4  * Copyright (C) 2014 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 <asm/neon.h>
12 #include <asm/unaligned.h>
13 #include <crypto/internal/hash.h>
14 #include <crypto/sha.h>
15 #include <crypto/sha1_base.h>
16 #include <linux/cpufeature.h>
17 #include <linux/crypto.h>
18 #include <linux/module.h>
19 
20 #define ASM_EXPORT(sym, val) \
21 	asm(".globl " #sym "; .set " #sym ", %0" :: "I"(val));
22 
23 MODULE_DESCRIPTION("SHA1 secure hash using ARMv8 Crypto Extensions");
24 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
25 MODULE_LICENSE("GPL v2");
26 
27 struct sha1_ce_state {
28 	struct sha1_state	sst;
29 	u32			finalize;
30 };
31 
32 asmlinkage void sha1_ce_transform(struct sha1_ce_state *sst, u8 const *src,
33 				  int blocks);
34 
35 static int sha1_ce_update(struct shash_desc *desc, const u8 *data,
36 			  unsigned int len)
37 {
38 	struct sha1_ce_state *sctx = shash_desc_ctx(desc);
39 
40 	sctx->finalize = 0;
41 	kernel_neon_begin_partial(16);
42 	sha1_base_do_update(desc, data, len,
43 			    (sha1_block_fn *)sha1_ce_transform);
44 	kernel_neon_end();
45 
46 	return 0;
47 }
48 
49 static int sha1_ce_finup(struct shash_desc *desc, const u8 *data,
50 			 unsigned int len, u8 *out)
51 {
52 	struct sha1_ce_state *sctx = shash_desc_ctx(desc);
53 	bool finalize = !sctx->sst.count && !(len % SHA1_BLOCK_SIZE);
54 
55 	ASM_EXPORT(sha1_ce_offsetof_count,
56 		   offsetof(struct sha1_ce_state, sst.count));
57 	ASM_EXPORT(sha1_ce_offsetof_finalize,
58 		   offsetof(struct sha1_ce_state, finalize));
59 
60 	/*
61 	 * Allow the asm code to perform the finalization if there is no
62 	 * partial data and the input is a round multiple of the block size.
63 	 */
64 	sctx->finalize = finalize;
65 
66 	kernel_neon_begin_partial(16);
67 	sha1_base_do_update(desc, data, len,
68 			    (sha1_block_fn *)sha1_ce_transform);
69 	if (!finalize)
70 		sha1_base_do_finalize(desc, (sha1_block_fn *)sha1_ce_transform);
71 	kernel_neon_end();
72 	return sha1_base_finish(desc, out);
73 }
74 
75 static int sha1_ce_final(struct shash_desc *desc, u8 *out)
76 {
77 	struct sha1_ce_state *sctx = shash_desc_ctx(desc);
78 
79 	sctx->finalize = 0;
80 	kernel_neon_begin_partial(16);
81 	sha1_base_do_finalize(desc, (sha1_block_fn *)sha1_ce_transform);
82 	kernel_neon_end();
83 	return sha1_base_finish(desc, out);
84 }
85 
86 static struct shash_alg alg = {
87 	.init			= sha1_base_init,
88 	.update			= sha1_ce_update,
89 	.final			= sha1_ce_final,
90 	.finup			= sha1_ce_finup,
91 	.descsize		= sizeof(struct sha1_ce_state),
92 	.digestsize		= SHA1_DIGEST_SIZE,
93 	.base			= {
94 		.cra_name		= "sha1",
95 		.cra_driver_name	= "sha1-ce",
96 		.cra_priority		= 200,
97 		.cra_flags		= CRYPTO_ALG_TYPE_SHASH,
98 		.cra_blocksize		= SHA1_BLOCK_SIZE,
99 		.cra_module		= THIS_MODULE,
100 	}
101 };
102 
103 static int __init sha1_ce_mod_init(void)
104 {
105 	return crypto_register_shash(&alg);
106 }
107 
108 static void __exit sha1_ce_mod_fini(void)
109 {
110 	crypto_unregister_shash(&alg);
111 }
112 
113 module_cpu_feature_match(SHA1, sha1_ce_mod_init);
114 module_exit(sha1_ce_mod_fini);
115