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
|
// SPDX-License-Identifier: GPL-2.0
/*
* PowerNV code for secure variables
*
* Copyright (C) 2019 IBM Corporation
* Author: Claudio Carvalho
* Nayna Jain
*
* APIs to access secure variables managed by OPAL.
*/
#define pr_fmt(fmt) "secvar: "fmt
#include <linux/types.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <asm/opal.h>
#include <asm/secvar.h>
#include <asm/secure_boot.h>
static int opal_status_to_err(int rc)
{
int err;
switch (rc) {
case OPAL_SUCCESS:
err = 0;
break;
case OPAL_UNSUPPORTED:
err = -ENXIO;
break;
case OPAL_PARAMETER:
err = -EINVAL;
break;
case OPAL_RESOURCE:
err = -ENOSPC;
break;
case OPAL_HARDWARE:
err = -EIO;
break;
case OPAL_NO_MEM:
err = -ENOMEM;
break;
case OPAL_EMPTY:
err = -ENOENT;
break;
case OPAL_PARTIAL:
err = -EFBIG;
break;
default:
err = -EINVAL;
}
return err;
}
static int opal_get_variable(const char *key, u64 ksize, u8 *data, u64 *dsize)
{
int rc;
if (!key || !dsize)
return -EINVAL;
*dsize = cpu_to_be64(*dsize);
rc = opal_secvar_get(key, ksize, data, dsize);
*dsize = be64_to_cpu(*dsize);
return opal_status_to_err(rc);
}
static int opal_get_next_variable(const char *key, u64 *keylen, u64 keybufsize)
{
int rc;
if (!key || !keylen)
return -EINVAL;
*keylen = cpu_to_be64(*keylen);
rc = opal_secvar_get_next(key, keylen, keybufsize);
*keylen = be64_to_cpu(*keylen);
return opal_status_to_err(rc);
}
static int opal_set_variable(const char *key, u64 ksize, u8 *data, u64 dsize)
{
int rc;
if (!key || !data)
return -EINVAL;
rc = opal_secvar_enqueue_update(key, ksize, data, dsize);
return opal_status_to_err(rc);
}
static ssize_t opal_secvar_format(char *buf, size_t bufsize)
{
ssize_t rc = 0;
struct device_node *node;
const char *format;
node = of_find_compatible_node(NULL, NULL, "ibm,secvar-backend");
if (!of_device_is_available(node)) {
rc = -ENODEV;
goto out;
}
rc = of_property_read_string(node, "format", &format);
if (rc)
goto out;
rc = snprintf(buf, bufsize, "%s", format);
out:
of_node_put(node);
return rc;
}
static int opal_secvar_max_size(u64 *max_size)
{
int rc;
struct device_node *node;
node = of_find_compatible_node(NULL, NULL, "ibm,secvar-backend");
if (!node)
return -ENODEV;
if (!of_device_is_available(node)) {
rc = -ENODEV;
goto out;
}
rc = of_property_read_u64(node, "max-var-size", max_size);
out:
of_node_put(node);
return rc;
}
static const struct secvar_operations opal_secvar_ops = {
.get = opal_get_variable,
.get_next = opal_get_next_variable,
.set = opal_set_variable,
.format = opal_secvar_format,
.max_size = opal_secvar_max_size,
};
static int opal_secvar_probe(struct platform_device *pdev)
{
if (!opal_check_token(OPAL_SECVAR_GET)
|| !opal_check_token(OPAL_SECVAR_GET_NEXT)
|| !opal_check_token(OPAL_SECVAR_ENQUEUE_UPDATE)) {
pr_err("OPAL doesn't support secure variables\n");
return -ENODEV;
}
return set_secvar_ops(&opal_secvar_ops);
}
static const struct of_device_id opal_secvar_match[] = {
{ .compatible = "ibm,secvar-backend",},
{},
};
static struct platform_driver opal_secvar_driver = {
.driver = {
.name = "secvar",
.of_match_table = opal_secvar_match,
},
};
static int __init opal_secvar_init(void)
{
return platform_driver_probe(&opal_secvar_driver, opal_secvar_probe);
}
device_initcall(opal_secvar_init);
|
