1/*
2 * Cryptographic API.
3 *
4 * SHA-224 and SHA-256 Secure Hash Algorithm.
5 *
6 * Adapted for OCTEON by Aaro Koskinen <aaro.koskinen@iki.fi>.
7 *
8 * Based on crypto/sha256_generic.c, which is:
9 *
10 * Copyright (c) Jean-Luc Cooke <jlcooke@certainkey.com>
11 * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
12 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
13 * SHA224 Support Copyright 2007 Intel Corporation <jonathan.lynch@intel.com>
14 *
15 * This program is free software; you can redistribute it and/or modify it
16 * under the terms of the GNU General Public License as published by the Free
17 * Software Foundation; either version 2 of the License, or (at your option)
18 * any later version.
19 */
20
21#include <linux/mm.h>
22#include <crypto/sha.h>
23#include <linux/init.h>
24#include <linux/types.h>
25#include <linux/module.h>
26#include <asm/byteorder.h>
27#include <asm/octeon/octeon.h>
28#include <crypto/internal/hash.h>
29
30#include "octeon-crypto.h"
31
32/*
33 * We pass everything as 64-bit. OCTEON can handle misaligned data.
34 */
35
36static void octeon_sha256_store_hash(struct sha256_state *sctx)
37{
38	u64 *hash = (u64 *)sctx->state;
39
40	write_octeon_64bit_hash_dword(hash[0], 0);
41	write_octeon_64bit_hash_dword(hash[1], 1);
42	write_octeon_64bit_hash_dword(hash[2], 2);
43	write_octeon_64bit_hash_dword(hash[3], 3);
44}
45
46static void octeon_sha256_read_hash(struct sha256_state *sctx)
47{
48	u64 *hash = (u64 *)sctx->state;
49
50	hash[0] = read_octeon_64bit_hash_dword(0);
51	hash[1] = read_octeon_64bit_hash_dword(1);
52	hash[2] = read_octeon_64bit_hash_dword(2);
53	hash[3] = read_octeon_64bit_hash_dword(3);
54}
55
56static void octeon_sha256_transform(const void *_block)
57{
58	const u64 *block = _block;
59
60	write_octeon_64bit_block_dword(block[0], 0);
61	write_octeon_64bit_block_dword(block[1], 1);
62	write_octeon_64bit_block_dword(block[2], 2);
63	write_octeon_64bit_block_dword(block[3], 3);
64	write_octeon_64bit_block_dword(block[4], 4);
65	write_octeon_64bit_block_dword(block[5], 5);
66	write_octeon_64bit_block_dword(block[6], 6);
67	octeon_sha256_start(block[7]);
68}
69
70static int octeon_sha224_init(struct shash_desc *desc)
71{
72	struct sha256_state *sctx = shash_desc_ctx(desc);
73
74	sctx->state[0] = SHA224_H0;
75	sctx->state[1] = SHA224_H1;
76	sctx->state[2] = SHA224_H2;
77	sctx->state[3] = SHA224_H3;
78	sctx->state[4] = SHA224_H4;
79	sctx->state[5] = SHA224_H5;
80	sctx->state[6] = SHA224_H6;
81	sctx->state[7] = SHA224_H7;
82	sctx->count = 0;
83
84	return 0;
85}
86
87static int octeon_sha256_init(struct shash_desc *desc)
88{
89	struct sha256_state *sctx = shash_desc_ctx(desc);
90
91	sctx->state[0] = SHA256_H0;
92	sctx->state[1] = SHA256_H1;
93	sctx->state[2] = SHA256_H2;
94	sctx->state[3] = SHA256_H3;
95	sctx->state[4] = SHA256_H4;
96	sctx->state[5] = SHA256_H5;
97	sctx->state[6] = SHA256_H6;
98	sctx->state[7] = SHA256_H7;
99	sctx->count = 0;
100
101	return 0;
102}
103
104static void __octeon_sha256_update(struct sha256_state *sctx, const u8 *data,
105				   unsigned int len)
106{
107	unsigned int partial;
108	unsigned int done;
109	const u8 *src;
110
111	partial = sctx->count % SHA256_BLOCK_SIZE;
112	sctx->count += len;
113	done = 0;
114	src = data;
115
116	if ((partial + len) >= SHA256_BLOCK_SIZE) {
117		if (partial) {
118			done = -partial;
119			memcpy(sctx->buf + partial, data,
120			       done + SHA256_BLOCK_SIZE);
121			src = sctx->buf;
122		}
123
124		do {
125			octeon_sha256_transform(src);
126			done += SHA256_BLOCK_SIZE;
127			src = data + done;
128		} while (done + SHA256_BLOCK_SIZE <= len);
129
130		partial = 0;
131	}
132	memcpy(sctx->buf + partial, src, len - done);
133}
134
135static int octeon_sha256_update(struct shash_desc *desc, const u8 *data,
136				unsigned int len)
137{
138	struct sha256_state *sctx = shash_desc_ctx(desc);
139	struct octeon_cop2_state state;
140	unsigned long flags;
141
142	/*
143	 * Small updates never reach the crypto engine, so the generic sha256 is
144	 * faster because of the heavyweight octeon_crypto_enable() /
145	 * octeon_crypto_disable().
146	 */
147	if ((sctx->count % SHA256_BLOCK_SIZE) + len < SHA256_BLOCK_SIZE)
148		return crypto_sha256_update(desc, data, len);
149
150	flags = octeon_crypto_enable(&state);
151	octeon_sha256_store_hash(sctx);
152
153	__octeon_sha256_update(sctx, data, len);
154
155	octeon_sha256_read_hash(sctx);
156	octeon_crypto_disable(&state, flags);
157
158	return 0;
159}
160
161static int octeon_sha256_final(struct shash_desc *desc, u8 *out)
162{
163	struct sha256_state *sctx = shash_desc_ctx(desc);
164	static const u8 padding[64] = { 0x80, };
165	struct octeon_cop2_state state;
166	__be32 *dst = (__be32 *)out;
167	unsigned int pad_len;
168	unsigned long flags;
169	unsigned int index;
170	__be64 bits;
171	int i;
172
173	/* Save number of bits. */
174	bits = cpu_to_be64(sctx->count << 3);
175
176	/* Pad out to 56 mod 64. */
177	index = sctx->count & 0x3f;
178	pad_len = (index < 56) ? (56 - index) : ((64+56) - index);
179
180	flags = octeon_crypto_enable(&state);
181	octeon_sha256_store_hash(sctx);
182
183	__octeon_sha256_update(sctx, padding, pad_len);
184
185	/* Append length (before padding). */
186	__octeon_sha256_update(sctx, (const u8 *)&bits, sizeof(bits));
187
188	octeon_sha256_read_hash(sctx);
189	octeon_crypto_disable(&state, flags);
190
191	/* Store state in digest */
192	for (i = 0; i < 8; i++)
193		dst[i] = cpu_to_be32(sctx->state[i]);
194
195	/* Zeroize sensitive information. */
196	memset(sctx, 0, sizeof(*sctx));
197
198	return 0;
199}
200
201static int octeon_sha224_final(struct shash_desc *desc, u8 *hash)
202{
203	u8 D[SHA256_DIGEST_SIZE];
204
205	octeon_sha256_final(desc, D);
206
207	memcpy(hash, D, SHA224_DIGEST_SIZE);
208	memzero_explicit(D, SHA256_DIGEST_SIZE);
209
210	return 0;
211}
212
213static int octeon_sha256_export(struct shash_desc *desc, void *out)
214{
215	struct sha256_state *sctx = shash_desc_ctx(desc);
216
217	memcpy(out, sctx, sizeof(*sctx));
218	return 0;
219}
220
221static int octeon_sha256_import(struct shash_desc *desc, const void *in)
222{
223	struct sha256_state *sctx = shash_desc_ctx(desc);
224
225	memcpy(sctx, in, sizeof(*sctx));
226	return 0;
227}
228
229static struct shash_alg octeon_sha256_algs[2] = { {
230	.digestsize	=	SHA256_DIGEST_SIZE,
231	.init		=	octeon_sha256_init,
232	.update		=	octeon_sha256_update,
233	.final		=	octeon_sha256_final,
234	.export		=	octeon_sha256_export,
235	.import		=	octeon_sha256_import,
236	.descsize	=	sizeof(struct sha256_state),
237	.statesize	=	sizeof(struct sha256_state),
238	.base		=	{
239		.cra_name	=	"sha256",
240		.cra_driver_name=	"octeon-sha256",
241		.cra_priority	=	OCTEON_CR_OPCODE_PRIORITY,
242		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
243		.cra_blocksize	=	SHA256_BLOCK_SIZE,
244		.cra_module	=	THIS_MODULE,
245	}
246}, {
247	.digestsize	=	SHA224_DIGEST_SIZE,
248	.init		=	octeon_sha224_init,
249	.update		=	octeon_sha256_update,
250	.final		=	octeon_sha224_final,
251	.descsize	=	sizeof(struct sha256_state),
252	.base		=	{
253		.cra_name	=	"sha224",
254		.cra_driver_name=	"octeon-sha224",
255		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
256		.cra_blocksize	=	SHA224_BLOCK_SIZE,
257		.cra_module	=	THIS_MODULE,
258	}
259} };
260
261static int __init octeon_sha256_mod_init(void)
262{
263	if (!octeon_has_crypto())
264		return -ENOTSUPP;
265	return crypto_register_shashes(octeon_sha256_algs,
266				       ARRAY_SIZE(octeon_sha256_algs));
267}
268
269static void __exit octeon_sha256_mod_fini(void)
270{
271	crypto_unregister_shashes(octeon_sha256_algs,
272				  ARRAY_SIZE(octeon_sha256_algs));
273}
274
275module_init(octeon_sha256_mod_init);
276module_exit(octeon_sha256_mod_fini);
277
278MODULE_LICENSE("GPL");
279MODULE_DESCRIPTION("SHA-224 and SHA-256 Secure Hash Algorithm (OCTEON)");
280MODULE_AUTHOR("Aaro Koskinen <aaro.koskinen@iki.fi>");
281