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
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
|
/*
* mgmt-masterkey.c
* ----------------
* Masterkey CLI functions.
*
* Copyright (c) 2016, NORDUnet A/S All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of the NORDUnet nor the names of its contributors may
* be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/* Rename both CMSIS HAL_OK and libhal HAL_OK to disambiguate */
#define HAL_OK CMSIS_HAL_OK
#include "stm-init.h"
#include "stm-uart.h"
#include "mgmt-cli.h"
#include "mgmt-masterkey.h"
#undef HAL_OK
#define LIBHAL_OK HAL_OK
#include <hal.h>
#warning Refactor so we do not need to include hal_internal.h here
#include <hal_internal.h>
#undef HAL_OK
#include <stdlib.h>
static char * _status2str(const hal_error_t status)
{
switch (status) {
case LIBHAL_OK:
return (char *) "Set";
case HAL_ERROR_MASTERKEY_NOT_SET:
return (char *) "Not set";
default:
return (char *) "Unknown";
}
}
static int cmd_masterkey_status(struct cli_def *cli, const char *command, char *argv[], int argc)
{
hal_error_t status;
command = command;
argv = argv;
argc = argc;
cli_print(cli, "Status of master key:\n");
status = hal_mkm_volatile_read(NULL, 0);
cli_print(cli, " volatile: %s / %s", _status2str(status), hal_error_string(status));
status = hal_mkm_flash_read(NULL, 0);
cli_print(cli, " flash: %s / %s", _status2str(status), hal_error_string(status));
return CLI_OK;
}
static int str_to_hex_digit(char c)
{
if (c >= '0' && c <= '9')
c -= '0';
else if (c >= 'a' && c <= 'f')
c = c - 'a' + 10;
else if (c >= 'A' && c <= 'F')
c = c - 'A' + 10;
else
return -1;
return c;
}
static inline char hex_to_str_digit(const uint8_t c)
{
return (c < 10) ? ((char)c + '0') : ((char)c + 'A' - 10);
}
static char *hexdump_kek(const uint8_t * const kek)
{
/* This is only for dumping masterkey values, so has no length checks.
* Do not use it for anything else.
*
* For convenience of possibly hand-copying and hand-retyping, the key
* is divided into 8 4-byte (8-character) groups.
*/
static char buf[2 * KEK_LENGTH + 8];
char *dst = buf;
for (size_t i = 0; i < KEK_LENGTH; ++i) {
uint8_t b = kek[i];
*dst++ = hex_to_str_digit(b >> 4);
*dst++ = hex_to_str_digit(b & 0xf);
if ((i & 3) == 3)
*dst++ = ' ';
}
buf[sizeof(buf) - 1] = '\0';
return buf;
}
static int _masterkey_set(struct cli_def *cli, char *argv[], int argc,
char *label, hal_error_t (*writer)(const uint8_t * const, const size_t))
{
uint8_t buf[KEK_LENGTH] = {0};
hal_error_t err;
if (argc == 0) {
/* fill master key with yummy randomness */
if ((err = hal_get_random(NULL, buf, sizeof(buf))) != LIBHAL_OK) {
cli_print(cli, "Error getting random key: %s", hal_error_string(err));
return CLI_ERROR;
}
cli_print(cli, "Random key:\n%s", hexdump_kek(buf));
}
else {
/* input is 32 hex bytes, arranged however the user wants */
size_t len = 0;
for (int i = 0; i < argc; ++i) {
for (char *cp = argv[i]; *cp != '\0'; ) {
int c;
if ((c = str_to_hex_digit(*cp++)) < 0)
goto errout;
buf[len] = c << 4;
if ((c = str_to_hex_digit(*cp++)) < 0)
goto errout;
buf[len] |= c & 0xf;
if (++len > KEK_LENGTH)
goto errout;
}
}
if (len < KEK_LENGTH) {
errout:
cli_print(cli, "Failed parsing master key, expected exactly %d hex bytes", KEK_LENGTH);
return CLI_ERROR;
}
cli_print(cli, "Parsed key:\n%s", hexdump_kek(buf));
}
if ((err = writer(buf, sizeof(buf))) == LIBHAL_OK) {
cli_print(cli, "Master key set in %s memory", label);
} else {
cli_print(cli, "Failed writing key to %s memory: %s", label, hal_error_string(err));
}
if ((err = hal_aes_keywrap_zero(NULL)) != LIBHAL_OK) {
cli_print(cli, "Error zeroing keywrap core: %s", hal_error_string(err));
return CLI_ERROR;
}
return CLI_OK;
}
static int cmd_masterkey_set(struct cli_def *cli, const char *command, char *argv[], int argc)
{
command = command;
return _masterkey_set(cli, argv, argc, "volatile", hal_mkm_volatile_write);
}
static int cmd_masterkey_erase(struct cli_def *cli, const char *command, char *argv[], int argc)
{
hal_error_t err;
command = command;
argv = argv;
argc = argc;
if ((err = hal_mkm_volatile_erase(KEK_LENGTH)) == LIBHAL_OK) {
cli_print(cli, "Erased master key from volatile memory");
} else {
cli_print(cli, "Failed erasing master key from volatile memory: %s", hal_error_string(err));
}
return CLI_OK;
}
static int cmd_masterkey_unsecure_set(struct cli_def *cli, const char *command, char *argv[], int argc)
{
command = command;
return _masterkey_set(cli, argv, argc, "flash", hal_mkm_flash_write);
}
static int cmd_masterkey_unsecure_erase(struct cli_def *cli, const char *command, char *argv[], int argc)
{
hal_error_t err;
command = command;
argv = argv;
argc = argc;
if ((err = hal_mkm_flash_erase(KEK_LENGTH)) == LIBHAL_OK) {
cli_print(cli, "Erased unsecure master key from flash");
} else {
cli_print(cli, "Failed erasing unsecure master key from flash: %s", hal_error_string(err));
}
return CLI_OK;
}
void configure_cli_masterkey(struct cli_def *cli)
{
struct cli_command *c = cli_register_command(cli, NULL, "masterkey", NULL, 0, 0, NULL);
/* masterkey status */
cli_register_command(cli, c, "status", cmd_masterkey_status, 0, 0, "Show status of master key in RAM/flash");
/* masterkey set */
cli_register_command(cli, c, "set", cmd_masterkey_set, 0, 0, "Set the master key in the volatile Master Key Memory");
/* masterkey erase */
cli_register_command(cli, c, "erase", cmd_masterkey_erase, 0, 0, "Erase the master key from the volatile Master Key Memory");
struct cli_command *c_unsecure = cli_register_command(cli, c, "unsecure", NULL, 0, 0, NULL);
/* masterkey unsecure set */
cli_register_command(cli, c_unsecure, "set", cmd_masterkey_unsecure_set, 0, 0, "Set master key in unprotected flash memory (if unsure, DON'T)");
/* masterkey unsecure erase */
cli_register_command(cli, c_unsecure, "erase", cmd_masterkey_unsecure_erase, 0, 0, "Erase master key from unprotected flash memory");
}
|
