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
|
// SPDX-License-Identifier: GPL-2.0+
#include <config.h>
#include <dm.h>
#include <log.h>
#include <malloc.h>
#include <uboot_aes.h>
#define SW_KEY_SLOTS 2
struct sw_aes_priv {
u8 key_slots[SW_KEY_SLOTS][AES256_KEY_LENGTH];
u8 key_schedule[AES256_EXPAND_KEY_LENGTH];
u8 selected_slot;
u32 selected_key_size;
bool key_expanded;
};
static int prepare_aes(struct sw_aes_priv *priv)
{
if (!priv->selected_key_size) {
log_debug("%s: AES key size not set, setup a slot first\n", __func__);
return 1;
}
if (priv->key_expanded)
return 0;
priv->key_expanded = 1;
aes_expand_key(priv->key_slots[priv->selected_slot], priv->selected_key_size,
priv->key_schedule);
return 0;
}
static int sw_aes_ops_available_key_slots(struct udevice *dev)
{
return SW_KEY_SLOTS;
}
static int sw_aes_ops_select_key_slot(struct udevice *dev, u32 key_size, u8 slot)
{
struct sw_aes_priv *priv = dev_get_priv(dev);
if (slot >= SW_KEY_SLOTS)
return 1;
priv->selected_slot = slot;
priv->selected_key_size = key_size;
priv->key_expanded = 0;
return 0;
}
static int sw_aes_ops_set_key_for_key_slot(struct udevice *dev, u32 key_size,
u8 *key, u8 slot)
{
struct sw_aes_priv *priv = dev_get_priv(dev);
if (slot >= SW_KEY_SLOTS)
return 1;
memcpy(priv->key_slots[slot], key, key_size / 8);
if (priv->selected_slot == slot)
priv->selected_key_size = key_size;
priv->key_expanded = 0;
return 0;
}
static int sw_aes_ops_aes_ecb_encrypt(struct udevice *dev, u8 *src, u8 *dst,
u32 num_aes_blocks)
{
struct sw_aes_priv *priv = dev_get_priv(dev);
int ret;
ret = prepare_aes(priv);
if (ret)
return ret;
while (num_aes_blocks > 0) {
aes_encrypt(priv->selected_key_size, src, priv->key_schedule, dst);
num_aes_blocks -= 1;
src += AES_BLOCK_LENGTH;
dst += AES_BLOCK_LENGTH;
}
return 0;
}
static int sw_aes_ops_aes_ecb_decrypt(struct udevice *dev, u8 *src, u8 *dst,
u32 num_aes_blocks)
{
struct sw_aes_priv *priv = dev_get_priv(dev);
int ret;
ret = prepare_aes(priv);
if (ret)
return ret;
while (num_aes_blocks > 0) {
aes_decrypt(priv->selected_key_size, src, priv->key_schedule, dst);
num_aes_blocks -= 1;
src += AES_BLOCK_LENGTH;
dst += AES_BLOCK_LENGTH;
}
return 0;
}
static int sw_aes_ops_aes_cbc_encrypt(struct udevice *dev, u8 *iv, u8 *src,
u8 *dst, u32 num_aes_blocks)
{
struct sw_aes_priv *priv = dev_get_priv(dev);
int ret;
ret = prepare_aes(priv);
if (ret)
return ret;
aes_cbc_encrypt_blocks(priv->selected_key_size, priv->key_schedule, iv,
src, dst, num_aes_blocks);
return 0;
}
static int sw_aes_ops_aes_cbc_decrypt(struct udevice *dev, u8 *iv, u8 *src,
u8 *dst, u32 num_aes_blocks)
{
struct sw_aes_priv *priv = dev_get_priv(dev);
int ret;
ret = prepare_aes(priv);
if (ret)
return ret;
aes_cbc_decrypt_blocks(priv->selected_key_size, priv->key_schedule,
iv, src, dst, num_aes_blocks);
return 0;
}
static const struct aes_ops aes_ops_sw = {
.available_key_slots = sw_aes_ops_available_key_slots,
.select_key_slot = sw_aes_ops_select_key_slot,
.set_key_for_key_slot = sw_aes_ops_set_key_for_key_slot,
.aes_ecb_encrypt = sw_aes_ops_aes_ecb_encrypt,
.aes_ecb_decrypt = sw_aes_ops_aes_ecb_decrypt,
.aes_cbc_encrypt = sw_aes_ops_aes_cbc_encrypt,
.aes_cbc_decrypt = sw_aes_ops_aes_cbc_decrypt,
};
static const struct udevice_id sw_aes_ids[] = {
{ .compatible = "software-aes-engine" },
{ }
};
U_BOOT_DRIVER(aes_sw) = {
.name = "aes_sw",
.id = UCLASS_AES,
.of_match = sw_aes_ids,
.ops = &aes_ops_sw,
.priv_auto = sizeof(struct sw_aes_priv),
};
|
