xref: /linux/arch/mips/cavium-octeon/crypto/octeon-sha1.c (revision b85d45947951d23cb22d90caecf4c1eb81342c96)
1 /*
2  * Cryptographic API.
3  *
4  * SHA1 Secure Hash Algorithm.
5  *
6  * Adapted for OCTEON by Aaro Koskinen <aaro.koskinen@iki.fi>.
7  *
8  * Based on crypto/sha1_generic.c, which is:
9  *
10  * Copyright (c) Alan Smithee.
11  * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
12  * Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
13  *
14  * This program is free software; you can redistribute it and/or modify it
15  * under the terms of the GNU General Public License as published by the Free
16  * Software Foundation; either version 2 of the License, or (at your option)
17  * any later version.
18  */
19 
20 #include <linux/mm.h>
21 #include <crypto/sha.h>
22 #include <linux/init.h>
23 #include <linux/types.h>
24 #include <linux/module.h>
25 #include <asm/byteorder.h>
26 #include <asm/octeon/octeon.h>
27 #include <crypto/internal/hash.h>
28 
29 #include "octeon-crypto.h"
30 
31 /*
32  * We pass everything as 64-bit. OCTEON can handle misaligned data.
33  */
34 
35 static void octeon_sha1_store_hash(struct sha1_state *sctx)
36 {
37 	u64 *hash = (u64 *)sctx->state;
38 	union {
39 		u32 word[2];
40 		u64 dword;
41 	} hash_tail = { { sctx->state[4], } };
42 
43 	write_octeon_64bit_hash_dword(hash[0], 0);
44 	write_octeon_64bit_hash_dword(hash[1], 1);
45 	write_octeon_64bit_hash_dword(hash_tail.dword, 2);
46 	memzero_explicit(&hash_tail.word[0], sizeof(hash_tail.word[0]));
47 }
48 
49 static void octeon_sha1_read_hash(struct sha1_state *sctx)
50 {
51 	u64 *hash = (u64 *)sctx->state;
52 	union {
53 		u32 word[2];
54 		u64 dword;
55 	} hash_tail;
56 
57 	hash[0]		= read_octeon_64bit_hash_dword(0);
58 	hash[1]		= read_octeon_64bit_hash_dword(1);
59 	hash_tail.dword	= read_octeon_64bit_hash_dword(2);
60 	sctx->state[4]	= hash_tail.word[0];
61 	memzero_explicit(&hash_tail.dword, sizeof(hash_tail.dword));
62 }
63 
64 static void octeon_sha1_transform(const void *_block)
65 {
66 	const u64 *block = _block;
67 
68 	write_octeon_64bit_block_dword(block[0], 0);
69 	write_octeon_64bit_block_dword(block[1], 1);
70 	write_octeon_64bit_block_dword(block[2], 2);
71 	write_octeon_64bit_block_dword(block[3], 3);
72 	write_octeon_64bit_block_dword(block[4], 4);
73 	write_octeon_64bit_block_dword(block[5], 5);
74 	write_octeon_64bit_block_dword(block[6], 6);
75 	octeon_sha1_start(block[7]);
76 }
77 
78 static int octeon_sha1_init(struct shash_desc *desc)
79 {
80 	struct sha1_state *sctx = shash_desc_ctx(desc);
81 
82 	sctx->state[0] = SHA1_H0;
83 	sctx->state[1] = SHA1_H1;
84 	sctx->state[2] = SHA1_H2;
85 	sctx->state[3] = SHA1_H3;
86 	sctx->state[4] = SHA1_H4;
87 	sctx->count = 0;
88 
89 	return 0;
90 }
91 
92 static void __octeon_sha1_update(struct sha1_state *sctx, const u8 *data,
93 				 unsigned int len)
94 {
95 	unsigned int partial;
96 	unsigned int done;
97 	const u8 *src;
98 
99 	partial = sctx->count % SHA1_BLOCK_SIZE;
100 	sctx->count += len;
101 	done = 0;
102 	src = data;
103 
104 	if ((partial + len) >= SHA1_BLOCK_SIZE) {
105 		if (partial) {
106 			done = -partial;
107 			memcpy(sctx->buffer + partial, data,
108 			       done + SHA1_BLOCK_SIZE);
109 			src = sctx->buffer;
110 		}
111 
112 		do {
113 			octeon_sha1_transform(src);
114 			done += SHA1_BLOCK_SIZE;
115 			src = data + done;
116 		} while (done + SHA1_BLOCK_SIZE <= len);
117 
118 		partial = 0;
119 	}
120 	memcpy(sctx->buffer + partial, src, len - done);
121 }
122 
123 static int octeon_sha1_update(struct shash_desc *desc, const u8 *data,
124 			unsigned int len)
125 {
126 	struct sha1_state *sctx = shash_desc_ctx(desc);
127 	struct octeon_cop2_state state;
128 	unsigned long flags;
129 
130 	/*
131 	 * Small updates never reach the crypto engine, so the generic sha1 is
132 	 * faster because of the heavyweight octeon_crypto_enable() /
133 	 * octeon_crypto_disable().
134 	 */
135 	if ((sctx->count % SHA1_BLOCK_SIZE) + len < SHA1_BLOCK_SIZE)
136 		return crypto_sha1_update(desc, data, len);
137 
138 	flags = octeon_crypto_enable(&state);
139 	octeon_sha1_store_hash(sctx);
140 
141 	__octeon_sha1_update(sctx, data, len);
142 
143 	octeon_sha1_read_hash(sctx);
144 	octeon_crypto_disable(&state, flags);
145 
146 	return 0;
147 }
148 
149 static int octeon_sha1_final(struct shash_desc *desc, u8 *out)
150 {
151 	struct sha1_state *sctx = shash_desc_ctx(desc);
152 	static const u8 padding[64] = { 0x80, };
153 	struct octeon_cop2_state state;
154 	__be32 *dst = (__be32 *)out;
155 	unsigned int pad_len;
156 	unsigned long flags;
157 	unsigned int index;
158 	__be64 bits;
159 	int i;
160 
161 	/* Save number of bits. */
162 	bits = cpu_to_be64(sctx->count << 3);
163 
164 	/* Pad out to 56 mod 64. */
165 	index = sctx->count & 0x3f;
166 	pad_len = (index < 56) ? (56 - index) : ((64+56) - index);
167 
168 	flags = octeon_crypto_enable(&state);
169 	octeon_sha1_store_hash(sctx);
170 
171 	__octeon_sha1_update(sctx, padding, pad_len);
172 
173 	/* Append length (before padding). */
174 	__octeon_sha1_update(sctx, (const u8 *)&bits, sizeof(bits));
175 
176 	octeon_sha1_read_hash(sctx);
177 	octeon_crypto_disable(&state, flags);
178 
179 	/* Store state in digest */
180 	for (i = 0; i < 5; i++)
181 		dst[i] = cpu_to_be32(sctx->state[i]);
182 
183 	/* Zeroize sensitive information. */
184 	memset(sctx, 0, sizeof(*sctx));
185 
186 	return 0;
187 }
188 
189 static int octeon_sha1_export(struct shash_desc *desc, void *out)
190 {
191 	struct sha1_state *sctx = shash_desc_ctx(desc);
192 
193 	memcpy(out, sctx, sizeof(*sctx));
194 	return 0;
195 }
196 
197 static int octeon_sha1_import(struct shash_desc *desc, const void *in)
198 {
199 	struct sha1_state *sctx = shash_desc_ctx(desc);
200 
201 	memcpy(sctx, in, sizeof(*sctx));
202 	return 0;
203 }
204 
205 static struct shash_alg octeon_sha1_alg = {
206 	.digestsize	=	SHA1_DIGEST_SIZE,
207 	.init		=	octeon_sha1_init,
208 	.update		=	octeon_sha1_update,
209 	.final		=	octeon_sha1_final,
210 	.export		=	octeon_sha1_export,
211 	.import		=	octeon_sha1_import,
212 	.descsize	=	sizeof(struct sha1_state),
213 	.statesize	=	sizeof(struct sha1_state),
214 	.base		=	{
215 		.cra_name	=	"sha1",
216 		.cra_driver_name=	"octeon-sha1",
217 		.cra_priority	=	OCTEON_CR_OPCODE_PRIORITY,
218 		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
219 		.cra_blocksize	=	SHA1_BLOCK_SIZE,
220 		.cra_module	=	THIS_MODULE,
221 	}
222 };
223 
224 static int __init octeon_sha1_mod_init(void)
225 {
226 	if (!octeon_has_crypto())
227 		return -ENOTSUPP;
228 	return crypto_register_shash(&octeon_sha1_alg);
229 }
230 
231 static void __exit octeon_sha1_mod_fini(void)
232 {
233 	crypto_unregister_shash(&octeon_sha1_alg);
234 }
235 
236 module_init(octeon_sha1_mod_init);
237 module_exit(octeon_sha1_mod_fini);
238 
239 MODULE_LICENSE("GPL");
240 MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm (OCTEON)");
241 MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
242