1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Cryptographic API.
4  *
5  * SHA-224 and SHA-256 Secure Hash Algorithm.
6  *
7  * Adapted for OCTEON by Aaro Koskinen <aaro.koskinen@iki.fi>.
8  *
9  * Based on crypto/sha256_generic.c, which is:
10  *
11  * Copyright (c) Jean-Luc Cooke <jlcooke@certainkey.com>
12  * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
13  * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
14  * SHA224 Support Copyright 2007 Intel Corporation <jonathan.lynch@intel.com>
15  */
16 
17 #include <linux/mm.h>
18 #include <crypto/sha.h>
19 #include <linux/init.h>
20 #include <linux/types.h>
21 #include <linux/module.h>
22 #include <asm/byteorder.h>
23 #include <asm/octeon/octeon.h>
24 #include <crypto/internal/hash.h>
25 
26 #include "octeon-crypto.h"
27 
28 /*
29  * We pass everything as 64-bit. OCTEON can handle misaligned data.
30  */
31 
32 static void octeon_sha256_store_hash(struct sha256_state *sctx)
33 {
34 	u64 *hash = (u64 *)sctx->state;
35 
36 	write_octeon_64bit_hash_dword(hash[0], 0);
37 	write_octeon_64bit_hash_dword(hash[1], 1);
38 	write_octeon_64bit_hash_dword(hash[2], 2);
39 	write_octeon_64bit_hash_dword(hash[3], 3);
40 }
41 
42 static void octeon_sha256_read_hash(struct sha256_state *sctx)
43 {
44 	u64 *hash = (u64 *)sctx->state;
45 
46 	hash[0] = read_octeon_64bit_hash_dword(0);
47 	hash[1] = read_octeon_64bit_hash_dword(1);
48 	hash[2] = read_octeon_64bit_hash_dword(2);
49 	hash[3] = read_octeon_64bit_hash_dword(3);
50 }
51 
52 static void octeon_sha256_transform(const void *_block)
53 {
54 	const u64 *block = _block;
55 
56 	write_octeon_64bit_block_dword(block[0], 0);
57 	write_octeon_64bit_block_dword(block[1], 1);
58 	write_octeon_64bit_block_dword(block[2], 2);
59 	write_octeon_64bit_block_dword(block[3], 3);
60 	write_octeon_64bit_block_dword(block[4], 4);
61 	write_octeon_64bit_block_dword(block[5], 5);
62 	write_octeon_64bit_block_dword(block[6], 6);
63 	octeon_sha256_start(block[7]);
64 }
65 
66 static int octeon_sha224_init(struct shash_desc *desc)
67 {
68 	struct sha256_state *sctx = shash_desc_ctx(desc);
69 
70 	sctx->state[0] = SHA224_H0;
71 	sctx->state[1] = SHA224_H1;
72 	sctx->state[2] = SHA224_H2;
73 	sctx->state[3] = SHA224_H3;
74 	sctx->state[4] = SHA224_H4;
75 	sctx->state[5] = SHA224_H5;
76 	sctx->state[6] = SHA224_H6;
77 	sctx->state[7] = SHA224_H7;
78 	sctx->count = 0;
79 
80 	return 0;
81 }
82 
83 static int octeon_sha256_init(struct shash_desc *desc)
84 {
85 	struct sha256_state *sctx = shash_desc_ctx(desc);
86 
87 	sctx->state[0] = SHA256_H0;
88 	sctx->state[1] = SHA256_H1;
89 	sctx->state[2] = SHA256_H2;
90 	sctx->state[3] = SHA256_H3;
91 	sctx->state[4] = SHA256_H4;
92 	sctx->state[5] = SHA256_H5;
93 	sctx->state[6] = SHA256_H6;
94 	sctx->state[7] = SHA256_H7;
95 	sctx->count = 0;
96 
97 	return 0;
98 }
99 
100 static void __octeon_sha256_update(struct sha256_state *sctx, const u8 *data,
101 				   unsigned int len)
102 {
103 	unsigned int partial;
104 	unsigned int done;
105 	const u8 *src;
106 
107 	partial = sctx->count % SHA256_BLOCK_SIZE;
108 	sctx->count += len;
109 	done = 0;
110 	src = data;
111 
112 	if ((partial + len) >= SHA256_BLOCK_SIZE) {
113 		if (partial) {
114 			done = -partial;
115 			memcpy(sctx->buf + partial, data,
116 			       done + SHA256_BLOCK_SIZE);
117 			src = sctx->buf;
118 		}
119 
120 		do {
121 			octeon_sha256_transform(src);
122 			done += SHA256_BLOCK_SIZE;
123 			src = data + done;
124 		} while (done + SHA256_BLOCK_SIZE <= len);
125 
126 		partial = 0;
127 	}
128 	memcpy(sctx->buf + partial, src, len - done);
129 }
130 
131 static int octeon_sha256_update(struct shash_desc *desc, const u8 *data,
132 				unsigned int len)
133 {
134 	struct sha256_state *sctx = shash_desc_ctx(desc);
135 	struct octeon_cop2_state state;
136 	unsigned long flags;
137 
138 	/*
139 	 * Small updates never reach the crypto engine, so the generic sha256 is
140 	 * faster because of the heavyweight octeon_crypto_enable() /
141 	 * octeon_crypto_disable().
142 	 */
143 	if ((sctx->count % SHA256_BLOCK_SIZE) + len < SHA256_BLOCK_SIZE)
144 		return crypto_sha256_update(desc, data, len);
145 
146 	flags = octeon_crypto_enable(&state);
147 	octeon_sha256_store_hash(sctx);
148 
149 	__octeon_sha256_update(sctx, data, len);
150 
151 	octeon_sha256_read_hash(sctx);
152 	octeon_crypto_disable(&state, flags);
153 
154 	return 0;
155 }
156 
157 static int octeon_sha256_final(struct shash_desc *desc, u8 *out)
158 {
159 	struct sha256_state *sctx = shash_desc_ctx(desc);
160 	static const u8 padding[64] = { 0x80, };
161 	struct octeon_cop2_state state;
162 	__be32 *dst = (__be32 *)out;
163 	unsigned int pad_len;
164 	unsigned long flags;
165 	unsigned int index;
166 	__be64 bits;
167 	int i;
168 
169 	/* Save number of bits. */
170 	bits = cpu_to_be64(sctx->count << 3);
171 
172 	/* Pad out to 56 mod 64. */
173 	index = sctx->count & 0x3f;
174 	pad_len = (index < 56) ? (56 - index) : ((64+56) - index);
175 
176 	flags = octeon_crypto_enable(&state);
177 	octeon_sha256_store_hash(sctx);
178 
179 	__octeon_sha256_update(sctx, padding, pad_len);
180 
181 	/* Append length (before padding). */
182 	__octeon_sha256_update(sctx, (const u8 *)&bits, sizeof(bits));
183 
184 	octeon_sha256_read_hash(sctx);
185 	octeon_crypto_disable(&state, flags);
186 
187 	/* Store state in digest */
188 	for (i = 0; i < 8; i++)
189 		dst[i] = cpu_to_be32(sctx->state[i]);
190 
191 	/* Zeroize sensitive information. */
192 	memset(sctx, 0, sizeof(*sctx));
193 
194 	return 0;
195 }
196 
197 static int octeon_sha224_final(struct shash_desc *desc, u8 *hash)
198 {
199 	u8 D[SHA256_DIGEST_SIZE];
200 
201 	octeon_sha256_final(desc, D);
202 
203 	memcpy(hash, D, SHA224_DIGEST_SIZE);
204 	memzero_explicit(D, SHA256_DIGEST_SIZE);
205 
206 	return 0;
207 }
208 
209 static int octeon_sha256_export(struct shash_desc *desc, void *out)
210 {
211 	struct sha256_state *sctx = shash_desc_ctx(desc);
212 
213 	memcpy(out, sctx, sizeof(*sctx));
214 	return 0;
215 }
216 
217 static int octeon_sha256_import(struct shash_desc *desc, const void *in)
218 {
219 	struct sha256_state *sctx = shash_desc_ctx(desc);
220 
221 	memcpy(sctx, in, sizeof(*sctx));
222 	return 0;
223 }
224 
225 static struct shash_alg octeon_sha256_algs[2] = { {
226 	.digestsize	=	SHA256_DIGEST_SIZE,
227 	.init		=	octeon_sha256_init,
228 	.update		=	octeon_sha256_update,
229 	.final		=	octeon_sha256_final,
230 	.export		=	octeon_sha256_export,
231 	.import		=	octeon_sha256_import,
232 	.descsize	=	sizeof(struct sha256_state),
233 	.statesize	=	sizeof(struct sha256_state),
234 	.base		=	{
235 		.cra_name	=	"sha256",
236 		.cra_driver_name=	"octeon-sha256",
237 		.cra_priority	=	OCTEON_CR_OPCODE_PRIORITY,
238 		.cra_blocksize	=	SHA256_BLOCK_SIZE,
239 		.cra_module	=	THIS_MODULE,
240 	}
241 }, {
242 	.digestsize	=	SHA224_DIGEST_SIZE,
243 	.init		=	octeon_sha224_init,
244 	.update		=	octeon_sha256_update,
245 	.final		=	octeon_sha224_final,
246 	.descsize	=	sizeof(struct sha256_state),
247 	.base		=	{
248 		.cra_name	=	"sha224",
249 		.cra_driver_name=	"octeon-sha224",
250 		.cra_blocksize	=	SHA224_BLOCK_SIZE,
251 		.cra_module	=	THIS_MODULE,
252 	}
253 } };
254 
255 static int __init octeon_sha256_mod_init(void)
256 {
257 	if (!octeon_has_crypto())
258 		return -ENOTSUPP;
259 	return crypto_register_shashes(octeon_sha256_algs,
260 				       ARRAY_SIZE(octeon_sha256_algs));
261 }
262 
263 static void __exit octeon_sha256_mod_fini(void)
264 {
265 	crypto_unregister_shashes(octeon_sha256_algs,
266 				  ARRAY_SIZE(octeon_sha256_algs));
267 }
268 
269 module_init(octeon_sha256_mod_init);
270 module_exit(octeon_sha256_mod_fini);
271 
272 MODULE_LICENSE("GPL");
273 MODULE_DESCRIPTION("SHA-224 and SHA-256 Secure Hash Algorithm (OCTEON)");
274 MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
275