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
|
/*
* Cryptographic API.
*
* s390 implementation of the GHASH algorithm for GCM (Galois/Counter Mode).
*
* Copyright IBM Corp. 2011
* Author(s): Gerald Schaefer <gerald.schaefer@de.ibm.com>
*/
#include <crypto/internal/hash.h>
#include <linux/module.h>
#include "crypt_s390.h"
#define GHASH_BLOCK_SIZE 16
#define GHASH_DIGEST_SIZE 16
struct ghash_ctx {
u8 icv[16];
u8 key[16];
};
struct ghash_desc_ctx {
u8 buffer[GHASH_BLOCK_SIZE];
u32 bytes;
};
static int ghash_init(struct shash_desc *desc)
{
struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
memset(dctx, 0, sizeof(*dctx));
return 0;
}
static int ghash_setkey(struct crypto_shash *tfm,
const u8 *key, unsigned int keylen)
{
struct ghash_ctx *ctx = crypto_shash_ctx(tfm);
if (keylen != GHASH_BLOCK_SIZE) {
crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
return -EINVAL;
}
memcpy(ctx->key, key, GHASH_BLOCK_SIZE);
memset(ctx->icv, 0, GHASH_BLOCK_SIZE);
return 0;
}
static int ghash_update(struct shash_desc *desc,
const u8 *src, unsigned int srclen)
{
struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
unsigned int n;
u8 *buf = dctx->buffer;
int ret;
if (dctx->bytes) {
u8 *pos = buf + (GHASH_BLOCK_SIZE - dctx->bytes);
n = min(srclen, dctx->bytes);
dctx->bytes -= n;
srclen -= n;
memcpy(pos, src, n);
src += n;
if (!dctx->bytes) {
ret = crypt_s390_kimd(KIMD_GHASH, ctx, buf,
GHASH_BLOCK_SIZE);
BUG_ON(ret != GHASH_BLOCK_SIZE);
}
}
n = srclen & ~(GHASH_BLOCK_SIZE - 1);
if (n) {
ret = crypt_s390_kimd(KIMD_GHASH, ctx, src, n);
BUG_ON(ret != n);
src += n;
srclen -= n;
}
if (srclen) {
dctx->bytes = GHASH_BLOCK_SIZE - srclen;
memcpy(buf, src, srclen);
}
return 0;
}
static void ghash_flush(struct ghash_ctx *ctx, struct ghash_desc_ctx *dctx)
{
u8 *buf = dctx->buffer;
int ret;
if (dctx->bytes) {
u8 *pos = buf + (GHASH_BLOCK_SIZE - dctx->bytes);
memset(pos, 0, dctx->bytes);
ret = crypt_s390_kimd(KIMD_GHASH, ctx, buf, GHASH_BLOCK_SIZE);
BUG_ON(ret != GHASH_BLOCK_SIZE);
}
dctx->bytes = 0;
}
static int ghash_final(struct shash_desc *desc, u8 *dst)
{
struct ghash_desc_ctx *dctx = shash_desc_ctx(desc);
struct ghash_ctx *ctx = crypto_shash_ctx(desc->tfm);
ghash_flush(ctx, dctx);
memcpy(dst, ctx->icv, GHASH_BLOCK_SIZE);
return 0;
}
static struct shash_alg ghash_alg = {
.digestsize = GHASH_DIGEST_SIZE,
.init = ghash_init,
.update = ghash_update,
.final = ghash_final,
.setkey = ghash_setkey,
.descsize = sizeof(struct ghash_desc_ctx),
.base = {
.cra_name = "ghash",
.cra_driver_name = "ghash-s390",
.cra_priority = CRYPT_S390_PRIORITY,
.cra_flags = CRYPTO_ALG_TYPE_SHASH,
.cra_blocksize = GHASH_BLOCK_SIZE,
.cra_ctxsize = sizeof(struct ghash_ctx),
.cra_module = THIS_MODULE,
},
};
static int __init ghash_mod_init(void)
{
if (!crypt_s390_func_available(KIMD_GHASH,
CRYPT_S390_MSA | CRYPT_S390_MSA4))
return -EOPNOTSUPP;
return crypto_register_shash(&ghash_alg);
}
static void __exit ghash_mod_exit(void)
{
crypto_unregister_shash(&ghash_alg);
}
module_init(ghash_mod_init);
module_exit(ghash_mod_exit);
MODULE_ALIAS("ghash");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("GHASH Message Digest Algorithm, s390 implementation");
|
