xref: /openbmc/linux/arch/sparc/crypto/sha256_glue.c (revision 9a29f5fc)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Glue code for SHA256 hashing optimized for sparc64 crypto opcodes.
3  *
4  * This is based largely upon crypto/sha256_generic.c
5  *
6  * Copyright (c) Jean-Luc Cooke <jlcooke@certainkey.com>
7  * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
8  * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
9  * SHA224 Support Copyright 2007 Intel Corporation <jonathan.lynch@intel.com>
10  */
11 
12 #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
13 
14 #include <crypto/internal/hash.h>
15 #include <linux/init.h>
16 #include <linux/module.h>
17 #include <linux/mm.h>
18 #include <linux/types.h>
19 #include <crypto/sha2.h>
20 #include <crypto/sha256_base.h>
21 
22 #include <asm/pstate.h>
23 #include <asm/elf.h>
24 
25 #include "opcodes.h"
26 
27 asmlinkage void sha256_sparc64_transform(u32 *digest, const char *data,
28 					 unsigned int rounds);
29 
30 static void __sha256_sparc64_update(struct sha256_state *sctx, const u8 *data,
31 				    unsigned int len, unsigned int partial)
32 {
33 	unsigned int done = 0;
34 
35 	sctx->count += len;
36 	if (partial) {
37 		done = SHA256_BLOCK_SIZE - partial;
38 		memcpy(sctx->buf + partial, data, done);
39 		sha256_sparc64_transform(sctx->state, sctx->buf, 1);
40 	}
41 	if (len - done >= SHA256_BLOCK_SIZE) {
42 		const unsigned int rounds = (len - done) / SHA256_BLOCK_SIZE;
43 
44 		sha256_sparc64_transform(sctx->state, data + done, rounds);
45 		done += rounds * SHA256_BLOCK_SIZE;
46 	}
47 
48 	memcpy(sctx->buf, data + done, len - done);
49 }
50 
51 static int sha256_sparc64_update(struct shash_desc *desc, const u8 *data,
52 				 unsigned int len)
53 {
54 	struct sha256_state *sctx = shash_desc_ctx(desc);
55 	unsigned int partial = sctx->count % SHA256_BLOCK_SIZE;
56 
57 	/* Handle the fast case right here */
58 	if (partial + len < SHA256_BLOCK_SIZE) {
59 		sctx->count += len;
60 		memcpy(sctx->buf + partial, data, len);
61 	} else
62 		__sha256_sparc64_update(sctx, data, len, partial);
63 
64 	return 0;
65 }
66 
67 static int sha256_sparc64_final(struct shash_desc *desc, u8 *out)
68 {
69 	struct sha256_state *sctx = shash_desc_ctx(desc);
70 	unsigned int i, index, padlen;
71 	__be32 *dst = (__be32 *)out;
72 	__be64 bits;
73 	static const u8 padding[SHA256_BLOCK_SIZE] = { 0x80, };
74 
75 	bits = cpu_to_be64(sctx->count << 3);
76 
77 	/* Pad out to 56 mod 64 and append length */
78 	index = sctx->count % SHA256_BLOCK_SIZE;
79 	padlen = (index < 56) ? (56 - index) : ((SHA256_BLOCK_SIZE+56) - index);
80 
81 	/* We need to fill a whole block for __sha256_sparc64_update() */
82 	if (padlen <= 56) {
83 		sctx->count += padlen;
84 		memcpy(sctx->buf + index, padding, padlen);
85 	} else {
86 		__sha256_sparc64_update(sctx, padding, padlen, index);
87 	}
88 	__sha256_sparc64_update(sctx, (const u8 *)&bits, sizeof(bits), 56);
89 
90 	/* Store state in digest */
91 	for (i = 0; i < 8; i++)
92 		dst[i] = cpu_to_be32(sctx->state[i]);
93 
94 	/* Wipe context */
95 	memset(sctx, 0, sizeof(*sctx));
96 
97 	return 0;
98 }
99 
100 static int sha224_sparc64_final(struct shash_desc *desc, u8 *hash)
101 {
102 	u8 D[SHA256_DIGEST_SIZE];
103 
104 	sha256_sparc64_final(desc, D);
105 
106 	memcpy(hash, D, SHA224_DIGEST_SIZE);
107 	memzero_explicit(D, SHA256_DIGEST_SIZE);
108 
109 	return 0;
110 }
111 
112 static int sha256_sparc64_export(struct shash_desc *desc, void *out)
113 {
114 	struct sha256_state *sctx = shash_desc_ctx(desc);
115 
116 	memcpy(out, sctx, sizeof(*sctx));
117 	return 0;
118 }
119 
120 static int sha256_sparc64_import(struct shash_desc *desc, const void *in)
121 {
122 	struct sha256_state *sctx = shash_desc_ctx(desc);
123 
124 	memcpy(sctx, in, sizeof(*sctx));
125 	return 0;
126 }
127 
128 static struct shash_alg sha256_alg = {
129 	.digestsize	=	SHA256_DIGEST_SIZE,
130 	.init		=	sha256_base_init,
131 	.update		=	sha256_sparc64_update,
132 	.final		=	sha256_sparc64_final,
133 	.export		=	sha256_sparc64_export,
134 	.import		=	sha256_sparc64_import,
135 	.descsize	=	sizeof(struct sha256_state),
136 	.statesize	=	sizeof(struct sha256_state),
137 	.base		=	{
138 		.cra_name	=	"sha256",
139 		.cra_driver_name=	"sha256-sparc64",
140 		.cra_priority	=	SPARC_CR_OPCODE_PRIORITY,
141 		.cra_blocksize	=	SHA256_BLOCK_SIZE,
142 		.cra_module	=	THIS_MODULE,
143 	}
144 };
145 
146 static struct shash_alg sha224_alg = {
147 	.digestsize	=	SHA224_DIGEST_SIZE,
148 	.init		=	sha224_base_init,
149 	.update		=	sha256_sparc64_update,
150 	.final		=	sha224_sparc64_final,
151 	.descsize	=	sizeof(struct sha256_state),
152 	.base		=	{
153 		.cra_name	=	"sha224",
154 		.cra_driver_name=	"sha224-sparc64",
155 		.cra_priority	=	SPARC_CR_OPCODE_PRIORITY,
156 		.cra_blocksize	=	SHA224_BLOCK_SIZE,
157 		.cra_module	=	THIS_MODULE,
158 	}
159 };
160 
161 static bool __init sparc64_has_sha256_opcode(void)
162 {
163 	unsigned long cfr;
164 
165 	if (!(sparc64_elf_hwcap & HWCAP_SPARC_CRYPTO))
166 		return false;
167 
168 	__asm__ __volatile__("rd %%asr26, %0" : "=r" (cfr));
169 	if (!(cfr & CFR_SHA256))
170 		return false;
171 
172 	return true;
173 }
174 
175 static int __init sha256_sparc64_mod_init(void)
176 {
177 	if (sparc64_has_sha256_opcode()) {
178 		int ret = crypto_register_shash(&sha224_alg);
179 		if (ret < 0)
180 			return ret;
181 
182 		ret = crypto_register_shash(&sha256_alg);
183 		if (ret < 0) {
184 			crypto_unregister_shash(&sha224_alg);
185 			return ret;
186 		}
187 
188 		pr_info("Using sparc64 sha256 opcode optimized SHA-256/SHA-224 implementation\n");
189 		return 0;
190 	}
191 	pr_info("sparc64 sha256 opcode not available.\n");
192 	return -ENODEV;
193 }
194 
195 static void __exit sha256_sparc64_mod_fini(void)
196 {
197 	crypto_unregister_shash(&sha224_alg);
198 	crypto_unregister_shash(&sha256_alg);
199 }
200 
201 module_init(sha256_sparc64_mod_init);
202 module_exit(sha256_sparc64_mod_fini);
203 
204 MODULE_LICENSE("GPL");
205 MODULE_DESCRIPTION("SHA-224 and SHA-256 Secure Hash Algorithm, sparc64 sha256 opcode accelerated");
206 
207 MODULE_ALIAS_CRYPTO("sha224");
208 MODULE_ALIAS_CRYPTO("sha256");
209 
210 #include "crop_devid.c"
211