1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
|
// SPDX-License-Identifier: GPL-2.0-only
/*
* Glue code for POLYVAL using PCMULQDQ-NI
*
* Copyright (c) 2007 Nokia Siemens Networks - Mikko Herranen <mh1@iki.fi>
* Copyright (c) 2009 Intel Corp.
* Author: Huang Ying <ying.huang@intel.com>
* Copyright 2021 Google LLC
*/
/*
* Glue code based on ghash-clmulni-intel_glue.c.
*
* This implementation of POLYVAL uses montgomery multiplication
* accelerated by PCLMULQDQ-NI to implement the finite field
* operations.
*/
#include <crypto/algapi.h>
#include <crypto/internal/hash.h>
#include <crypto/internal/simd.h>
#include <crypto/polyval.h>
#include <linux/crypto.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <asm/cpu_device_id.h>
#include <asm/simd.h>
#define POLYVAL_ALIGN 16
#define POLYVAL_ALIGN_ATTR __aligned(POLYVAL_ALIGN)
#define POLYVAL_ALIGN_EXTRA ((POLYVAL_ALIGN - 1) & ~(CRYPTO_MINALIGN - 1))
#define POLYVAL_CTX_SIZE (sizeof(struct polyval_tfm_ctx) + POLYVAL_ALIGN_EXTRA)
#define NUM_KEY_POWERS 8
struct polyval_tfm_ctx {
/*
* These powers must be in the order h^8, ..., h^1.
*/
u8 key_powers[NUM_KEY_POWERS][POLYVAL_BLOCK_SIZE] POLYVAL_ALIGN_ATTR;
};
struct polyval_desc_ctx {
u8 buffer[POLYVAL_BLOCK_SIZE];
u32 bytes;
};
asmlinkage void clmul_polyval_update(const struct polyval_tfm_ctx *keys,
const u8 *in, size_t nblocks, u8 *accumulator);
asmlinkage void clmul_polyval_mul(u8 *op1, const u8 *op2);
static inline struct polyval_tfm_ctx *polyval_tfm_ctx(struct crypto_shash *tfm)
{
return PTR_ALIGN(crypto_shash_ctx(tfm), POLYVAL_ALIGN);
}
static void internal_polyval_update(const struct polyval_tfm_ctx *keys,
const u8 *in, size_t nblocks, u8 *accumulator)
{
if (likely(crypto_simd_usable())) {
kernel_fpu_begin();
clmul_polyval_update(keys, in, nblocks, accumulator);
kernel_fpu_end();
} else {
polyval_update_non4k(keys->key_powers[NUM_KEY_POWERS-1], in,
nblocks, accumulator);
}
}
static void internal_polyval_mul(u8 *op1, const u8 *op2)
{
if (likely(crypto_simd_usable())) {
kernel_fpu_begin();
clmul_polyval_mul(op1, op2);
kernel_fpu_end();
} else {
polyval_mul_non4k(op1, op2);
}
}
static int polyval_x86_setkey(struct crypto_shash *tfm,
const u8 *key, unsigned int keylen)
{
struct polyval_tfm_ctx *tctx = polyval_tfm_ctx(tfm);
int i;
if (keylen != POLYVAL_BLOCK_SIZE)
return -EINVAL;
memcpy(tctx->key_powers[NUM_KEY_POWERS-1], key, POLYVAL_BLOCK_SIZE);
for (i = NUM_KEY_POWERS-2; i >= 0; i--) {
memcpy(tctx->key_powers[i], key, POLYVAL_BLOCK_SIZE);
internal_polyval_mul(tctx->key_powers[i],
tctx->key_powers[i+1]);
}
return 0;
}
static int polyval_x86_init(struct shash_desc *desc)
{
struct polyval_desc_ctx *dctx = shash_desc_ctx(desc);
memset(dctx, 0, sizeof(*dctx));
return 0;
}
static int polyval_x86_update(struct shash_desc *desc,
const u8 *src, unsigned int srclen)
{
struct polyval_desc_ctx *dctx = shash_desc_ctx(desc);
const struct polyval_tfm_ctx *tctx = polyval_tfm_ctx(desc->tfm);
u8 *pos;
unsigned int nblocks;
unsigned int n;
if (dctx->bytes) {
n = min(srclen, dctx->bytes);
pos = dctx->buffer + POLYVAL_BLOCK_SIZE - dctx->bytes;
dctx->bytes -= n;
srclen -= n;
while (n--)
*pos++ ^= *src++;
if (!dctx->bytes)
internal_polyval_mul(dctx->buffer,
tctx->key_powers[NUM_KEY_POWERS-1]);
}
while (srclen >= POLYVAL_BLOCK_SIZE) {
/* Allow rescheduling every 4K bytes. */
nblocks = min(srclen, 4096U) / POLYVAL_BLOCK_SIZE;
internal_polyval_update(tctx, src, nblocks, dctx->buffer);
srclen -= nblocks * POLYVAL_BLOCK_SIZE;
src += nblocks * POLYVAL_BLOCK_SIZE;
}
if (srclen) {
dctx->bytes = POLYVAL_BLOCK_SIZE - srclen;
pos = dctx->buffer;
while (srclen--)
*pos++ ^= *src++;
}
return 0;
}
static int polyval_x86_final(struct shash_desc *desc, u8 *dst)
{
struct polyval_desc_ctx *dctx = shash_desc_ctx(desc);
const struct polyval_tfm_ctx *tctx = polyval_tfm_ctx(desc->tfm);
if (dctx->bytes) {
internal_polyval_mul(dctx->buffer,
tctx->key_powers[NUM_KEY_POWERS-1]);
}
memcpy(dst, dctx->buffer, POLYVAL_BLOCK_SIZE);
return 0;
}
static struct shash_alg polyval_alg = {
.digestsize = POLYVAL_DIGEST_SIZE,
.init = polyval_x86_init,
.update = polyval_x86_update,
.final = polyval_x86_final,
.setkey = polyval_x86_setkey,
.descsize = sizeof(struct polyval_desc_ctx),
.base = {
.cra_name = "polyval",
.cra_driver_name = "polyval-clmulni",
.cra_priority = 200,
.cra_blocksize = POLYVAL_BLOCK_SIZE,
.cra_ctxsize = POLYVAL_CTX_SIZE,
.cra_module = THIS_MODULE,
},
};
__maybe_unused static const struct x86_cpu_id pcmul_cpu_id[] = {
X86_MATCH_FEATURE(X86_FEATURE_PCLMULQDQ, NULL),
{}
};
MODULE_DEVICE_TABLE(x86cpu, pcmul_cpu_id);
static int __init polyval_clmulni_mod_init(void)
{
if (!x86_match_cpu(pcmul_cpu_id))
return -ENODEV;
if (!boot_cpu_has(X86_FEATURE_AVX))
return -ENODEV;
return crypto_register_shash(&polyval_alg);
}
static void __exit polyval_clmulni_mod_exit(void)
{
crypto_unregister_shash(&polyval_alg);
}
module_init(polyval_clmulni_mod_init);
module_exit(polyval_clmulni_mod_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("POLYVAL hash function accelerated by PCLMULQDQ-NI");
MODULE_ALIAS_CRYPTO("polyval");
MODULE_ALIAS_CRYPTO("polyval-clmulni");
|
