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/sha2.h>
19 #include <crypto/sha256_base.h>
20 #include <linux/init.h>
21 #include <linux/types.h>
22 #include <linux/module.h>
23 #include <asm/byteorder.h>
24 #include <asm/octeon/octeon.h>
25 #include <crypto/internal/hash.h>
26 
27 #include "octeon-crypto.h"
28 
29 /*
30  * We pass everything as 64-bit. OCTEON can handle misaligned data.
31  */
32 
octeon_sha256_store_hash(struct sha256_state * sctx)33 static void octeon_sha256_store_hash(struct sha256_state *sctx)
34 {
35 	u64 *hash = (u64 *)sctx->state;
36 
37 	write_octeon_64bit_hash_dword(hash[0], 0);
38 	write_octeon_64bit_hash_dword(hash[1], 1);
39 	write_octeon_64bit_hash_dword(hash[2], 2);
40 	write_octeon_64bit_hash_dword(hash[3], 3);
41 }
42 
octeon_sha256_read_hash(struct sha256_state * sctx)43 static void octeon_sha256_read_hash(struct sha256_state *sctx)
44 {
45 	u64 *hash = (u64 *)sctx->state;
46 
47 	hash[0] = read_octeon_64bit_hash_dword(0);
48 	hash[1] = read_octeon_64bit_hash_dword(1);
49 	hash[2] = read_octeon_64bit_hash_dword(2);
50 	hash[3] = read_octeon_64bit_hash_dword(3);
51 }
52 
octeon_sha256_transform(const void * _block)53 static void octeon_sha256_transform(const void *_block)
54 {
55 	const u64 *block = _block;
56 
57 	write_octeon_64bit_block_dword(block[0], 0);
58 	write_octeon_64bit_block_dword(block[1], 1);
59 	write_octeon_64bit_block_dword(block[2], 2);
60 	write_octeon_64bit_block_dword(block[3], 3);
61 	write_octeon_64bit_block_dword(block[4], 4);
62 	write_octeon_64bit_block_dword(block[5], 5);
63 	write_octeon_64bit_block_dword(block[6], 6);
64 	octeon_sha256_start(block[7]);
65 }
66 
__octeon_sha256_update(struct sha256_state * sctx,const u8 * data,unsigned int len)67 static void __octeon_sha256_update(struct sha256_state *sctx, const u8 *data,
68 				   unsigned int len)
69 {
70 	unsigned int partial;
71 	unsigned int done;
72 	const u8 *src;
73 
74 	partial = sctx->count % SHA256_BLOCK_SIZE;
75 	sctx->count += len;
76 	done = 0;
77 	src = data;
78 
79 	if ((partial + len) >= SHA256_BLOCK_SIZE) {
80 		if (partial) {
81 			done = -partial;
82 			memcpy(sctx->buf + partial, data,
83 			       done + SHA256_BLOCK_SIZE);
84 			src = sctx->buf;
85 		}
86 
87 		do {
88 			octeon_sha256_transform(src);
89 			done += SHA256_BLOCK_SIZE;
90 			src = data + done;
91 		} while (done + SHA256_BLOCK_SIZE <= len);
92 
93 		partial = 0;
94 	}
95 	memcpy(sctx->buf + partial, src, len - done);
96 }
97 
octeon_sha256_update(struct shash_desc * desc,const u8 * data,unsigned int len)98 static int octeon_sha256_update(struct shash_desc *desc, const u8 *data,
99 				unsigned int len)
100 {
101 	struct sha256_state *sctx = shash_desc_ctx(desc);
102 	struct octeon_cop2_state state;
103 	unsigned long flags;
104 
105 	/*
106 	 * Small updates never reach the crypto engine, so the generic sha256 is
107 	 * faster because of the heavyweight octeon_crypto_enable() /
108 	 * octeon_crypto_disable().
109 	 */
110 	if ((sctx->count % SHA256_BLOCK_SIZE) + len < SHA256_BLOCK_SIZE)
111 		return crypto_sha256_update(desc, data, len);
112 
113 	flags = octeon_crypto_enable(&state);
114 	octeon_sha256_store_hash(sctx);
115 
116 	__octeon_sha256_update(sctx, data, len);
117 
118 	octeon_sha256_read_hash(sctx);
119 	octeon_crypto_disable(&state, flags);
120 
121 	return 0;
122 }
123 
octeon_sha256_final(struct shash_desc * desc,u8 * out)124 static int octeon_sha256_final(struct shash_desc *desc, u8 *out)
125 {
126 	struct sha256_state *sctx = shash_desc_ctx(desc);
127 	static const u8 padding[64] = { 0x80, };
128 	struct octeon_cop2_state state;
129 	__be32 *dst = (__be32 *)out;
130 	unsigned int pad_len;
131 	unsigned long flags;
132 	unsigned int index;
133 	__be64 bits;
134 	int i;
135 
136 	/* Save number of bits. */
137 	bits = cpu_to_be64(sctx->count << 3);
138 
139 	/* Pad out to 56 mod 64. */
140 	index = sctx->count & 0x3f;
141 	pad_len = (index < 56) ? (56 - index) : ((64+56) - index);
142 
143 	flags = octeon_crypto_enable(&state);
144 	octeon_sha256_store_hash(sctx);
145 
146 	__octeon_sha256_update(sctx, padding, pad_len);
147 
148 	/* Append length (before padding). */
149 	__octeon_sha256_update(sctx, (const u8 *)&bits, sizeof(bits));
150 
151 	octeon_sha256_read_hash(sctx);
152 	octeon_crypto_disable(&state, flags);
153 
154 	/* Store state in digest */
155 	for (i = 0; i < 8; i++)
156 		dst[i] = cpu_to_be32(sctx->state[i]);
157 
158 	/* Zeroize sensitive information. */
159 	memset(sctx, 0, sizeof(*sctx));
160 
161 	return 0;
162 }
163 
octeon_sha224_final(struct shash_desc * desc,u8 * hash)164 static int octeon_sha224_final(struct shash_desc *desc, u8 *hash)
165 {
166 	u8 D[SHA256_DIGEST_SIZE];
167 
168 	octeon_sha256_final(desc, D);
169 
170 	memcpy(hash, D, SHA224_DIGEST_SIZE);
171 	memzero_explicit(D, SHA256_DIGEST_SIZE);
172 
173 	return 0;
174 }
175 
octeon_sha256_export(struct shash_desc * desc,void * out)176 static int octeon_sha256_export(struct shash_desc *desc, void *out)
177 {
178 	struct sha256_state *sctx = shash_desc_ctx(desc);
179 
180 	memcpy(out, sctx, sizeof(*sctx));
181 	return 0;
182 }
183 
octeon_sha256_import(struct shash_desc * desc,const void * in)184 static int octeon_sha256_import(struct shash_desc *desc, const void *in)
185 {
186 	struct sha256_state *sctx = shash_desc_ctx(desc);
187 
188 	memcpy(sctx, in, sizeof(*sctx));
189 	return 0;
190 }
191 
192 static struct shash_alg octeon_sha256_algs[2] = { {
193 	.digestsize	=	SHA256_DIGEST_SIZE,
194 	.init		=	sha256_base_init,
195 	.update		=	octeon_sha256_update,
196 	.final		=	octeon_sha256_final,
197 	.export		=	octeon_sha256_export,
198 	.import		=	octeon_sha256_import,
199 	.descsize	=	sizeof(struct sha256_state),
200 	.statesize	=	sizeof(struct sha256_state),
201 	.base		=	{
202 		.cra_name	=	"sha256",
203 		.cra_driver_name=	"octeon-sha256",
204 		.cra_priority	=	OCTEON_CR_OPCODE_PRIORITY,
205 		.cra_blocksize	=	SHA256_BLOCK_SIZE,
206 		.cra_module	=	THIS_MODULE,
207 	}
208 }, {
209 	.digestsize	=	SHA224_DIGEST_SIZE,
210 	.init		=	sha224_base_init,
211 	.update		=	octeon_sha256_update,
212 	.final		=	octeon_sha224_final,
213 	.descsize	=	sizeof(struct sha256_state),
214 	.base		=	{
215 		.cra_name	=	"sha224",
216 		.cra_driver_name=	"octeon-sha224",
217 		.cra_blocksize	=	SHA224_BLOCK_SIZE,
218 		.cra_module	=	THIS_MODULE,
219 	}
220 } };
221 
octeon_sha256_mod_init(void)222 static int __init octeon_sha256_mod_init(void)
223 {
224 	if (!octeon_has_crypto())
225 		return -ENOTSUPP;
226 	return crypto_register_shashes(octeon_sha256_algs,
227 				       ARRAY_SIZE(octeon_sha256_algs));
228 }
229 
octeon_sha256_mod_fini(void)230 static void __exit octeon_sha256_mod_fini(void)
231 {
232 	crypto_unregister_shashes(octeon_sha256_algs,
233 				  ARRAY_SIZE(octeon_sha256_algs));
234 }
235 
236 module_init(octeon_sha256_mod_init);
237 module_exit(octeon_sha256_mod_fini);
238 
239 MODULE_LICENSE("GPL");
240 MODULE_DESCRIPTION("SHA-224 and SHA-256 Secure Hash Algorithm (OCTEON)");
241 MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
242