xref: /linux/arch/riscv/crypto/sha256-riscv64-glue.c (revision ef9226cd56b718c79184a3466d32984a51cb449c)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * SHA-256 and SHA-224 using the RISC-V vector crypto extensions
4  *
5  * Copyright (C) 2022 VRULL GmbH
6  * Author: Heiko Stuebner <heiko.stuebner@vrull.eu>
7  *
8  * Copyright (C) 2023 SiFive, Inc.
9  * Author: Jerry Shih <jerry.shih@sifive.com>
10  */
11 
12 #include <asm/simd.h>
13 #include <asm/vector.h>
14 #include <crypto/internal/hash.h>
15 #include <crypto/internal/simd.h>
16 #include <crypto/sha256_base.h>
17 #include <linux/linkage.h>
18 #include <linux/module.h>
19 
20 /*
21  * Note: the asm function only uses the 'state' field of struct sha256_state.
22  * It is assumed to be the first field.
23  */
24 asmlinkage void sha256_transform_zvknha_or_zvknhb_zvkb(
25 	struct sha256_state *state, const u8 *data, int num_blocks);
26 
27 static int riscv64_sha256_update(struct shash_desc *desc, const u8 *data,
28 				 unsigned int len)
29 {
30 	/*
31 	 * Ensure struct sha256_state begins directly with the SHA-256
32 	 * 256-bit internal state, as this is what the asm function expects.
33 	 */
34 	BUILD_BUG_ON(offsetof(struct sha256_state, state) != 0);
35 
36 	if (crypto_simd_usable()) {
37 		kernel_vector_begin();
38 		sha256_base_do_update(desc, data, len,
39 				      sha256_transform_zvknha_or_zvknhb_zvkb);
40 		kernel_vector_end();
41 	} else {
42 		crypto_sha256_update(desc, data, len);
43 	}
44 	return 0;
45 }
46 
47 static int riscv64_sha256_finup(struct shash_desc *desc, const u8 *data,
48 				unsigned int len, u8 *out)
49 {
50 	if (crypto_simd_usable()) {
51 		kernel_vector_begin();
52 		if (len)
53 			sha256_base_do_update(
54 				desc, data, len,
55 				sha256_transform_zvknha_or_zvknhb_zvkb);
56 		sha256_base_do_finalize(
57 			desc, sha256_transform_zvknha_or_zvknhb_zvkb);
58 		kernel_vector_end();
59 
60 		return sha256_base_finish(desc, out);
61 	}
62 
63 	return crypto_sha256_finup(desc, data, len, out);
64 }
65 
66 static int riscv64_sha256_final(struct shash_desc *desc, u8 *out)
67 {
68 	return riscv64_sha256_finup(desc, NULL, 0, out);
69 }
70 
71 static int riscv64_sha256_digest(struct shash_desc *desc, const u8 *data,
72 				 unsigned int len, u8 *out)
73 {
74 	return sha256_base_init(desc) ?:
75 	       riscv64_sha256_finup(desc, data, len, out);
76 }
77 
78 static struct shash_alg riscv64_sha256_algs[] = {
79 	{
80 		.init = sha256_base_init,
81 		.update = riscv64_sha256_update,
82 		.final = riscv64_sha256_final,
83 		.finup = riscv64_sha256_finup,
84 		.digest = riscv64_sha256_digest,
85 		.descsize = sizeof(struct sha256_state),
86 		.digestsize = SHA256_DIGEST_SIZE,
87 		.base = {
88 			.cra_blocksize = SHA256_BLOCK_SIZE,
89 			.cra_priority = 300,
90 			.cra_name = "sha256",
91 			.cra_driver_name = "sha256-riscv64-zvknha_or_zvknhb-zvkb",
92 			.cra_module = THIS_MODULE,
93 		},
94 	}, {
95 		.init = sha224_base_init,
96 		.update = riscv64_sha256_update,
97 		.final = riscv64_sha256_final,
98 		.finup = riscv64_sha256_finup,
99 		.descsize = sizeof(struct sha256_state),
100 		.digestsize = SHA224_DIGEST_SIZE,
101 		.base = {
102 			.cra_blocksize = SHA224_BLOCK_SIZE,
103 			.cra_priority = 300,
104 			.cra_name = "sha224",
105 			.cra_driver_name = "sha224-riscv64-zvknha_or_zvknhb-zvkb",
106 			.cra_module = THIS_MODULE,
107 		},
108 	},
109 };
110 
111 static int __init riscv64_sha256_mod_init(void)
112 {
113 	/* Both zvknha and zvknhb provide the SHA-256 instructions. */
114 	if ((riscv_isa_extension_available(NULL, ZVKNHA) ||
115 	     riscv_isa_extension_available(NULL, ZVKNHB)) &&
116 	    riscv_isa_extension_available(NULL, ZVKB) &&
117 	    riscv_vector_vlen() >= 128)
118 		return crypto_register_shashes(riscv64_sha256_algs,
119 					       ARRAY_SIZE(riscv64_sha256_algs));
120 
121 	return -ENODEV;
122 }
123 
124 static void __exit riscv64_sha256_mod_exit(void)
125 {
126 	crypto_unregister_shashes(riscv64_sha256_algs,
127 				  ARRAY_SIZE(riscv64_sha256_algs));
128 }
129 
130 module_init(riscv64_sha256_mod_init);
131 module_exit(riscv64_sha256_mod_exit);
132 
133 MODULE_DESCRIPTION("SHA-256 (RISC-V accelerated)");
134 MODULE_AUTHOR("Heiko Stuebner <heiko.stuebner@vrull.eu>");
135 MODULE_LICENSE("GPL");
136 MODULE_ALIAS_CRYPTO("sha256");
137 MODULE_ALIAS_CRYPTO("sha224");
138