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
|
/*
* ks_mmap.c
* ---------
* Keystore implementation over POSIX mmap().
*
* Authors: Rob Austein
* Copyright (c) 2015, 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.
*/
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <string.h>
#include <sys/errno.h>
#include <unistd.h>
#include "hal.h"
#include "hal_internal.h"
#ifndef HAL_KS_MMAP_FILE
#define HAL_KS_MMAP_FILE ".cryptech_hal_keystore"
#endif
#ifndef MAP_FILE
#define MAP_FILE 0
#endif
/*
* Storing the KEK in with the keys it's protecting is a bad idea, but we have no better
* place to put it (real protection requires dedicated hardware, which we don't have here).
*/
#define KEKBUF_LEN (bitsToBytes(256))
static hal_ks_keydb_t *db;
static uint8_t *kekbuf;
const hal_ks_keydb_t *hal_ks_get_keydb(void)
{
if (db != NULL)
return db;
const char * const env = getenv("CRYPTECH_KEYSTORE");
const char * const home = getenv("HOME");
const char * const base = HAL_KS_MMAP_FILE;
const long pagemask = sysconf(_SC_PAGESIZE) - 1;
const size_t len = (sizeof(hal_ks_keydb_t) + KEKBUF_LEN + pagemask) & ~pagemask;
char fn_[strlen(base) + (home == NULL ? 0 : strlen(home)) + 2];
const char *fn = fn_;
int fd;
if (pagemask < 0)
return NULL;
if (env != NULL)
fn = env;
else if (home == NULL)
fn = base;
else
strcat(strcat(strcpy(fn_, home), "/"), base);
if ((fd = open(fn, O_RDWR | O_CREAT | O_EXCL, 0600)) >= 0) {
uint8_t zeros[len];
memset(zeros, 0, sizeof(zeros));
(void) write(fd, zeros, sizeof(zeros));
}
else if (errno == EEXIST) {
fd = open(fn, O_RDWR | O_CREAT, 0600);
}
if (fd >= 0 && (db = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_FILE | MAP_SHARED, fd, 0)) != NULL)
kekbuf = (uint8_t *) (db + 1);
(void) close(fd);
return db;
}
hal_error_t hal_ks_set_keydb(const hal_ks_key_t * const key,
const int loc,
const int updating)
{
if (key == NULL || loc < 0 || loc >= sizeof(db->keys)/sizeof(*db->keys) || (!key->in_use != !updating))
return HAL_ERROR_BAD_ARGUMENTS;
db->keys[loc] = *key;
db->keys[loc].in_use = 1;
return HAL_OK;
}
hal_error_t hal_ks_del_keydb(const int loc)
{
if (loc < 0 || loc >= sizeof(db->keys)/sizeof(*db->keys))
return HAL_ERROR_BAD_ARGUMENTS;
db->keys[loc].in_use = 0;
memset(&db->keys[loc], 0, sizeof(db->keys[loc]));
return HAL_OK;
}
hal_error_t hal_set_pin(const hal_user_t user,
const hal_ks_pin_t * const pin)
{
if (pin == NULL)
return HAL_ERROR_BAD_ARGUMENTS;
hal_ks_pin_t *p = NULL;
switch (user) {
case HAL_USER_WHEEL: p = &db->wheel_pin; break;
case HAL_USER_SO: p = &db->so_pin; break;
case HAL_USER_NORMAL: p = &db->user_pin; break;
default: return HAL_ERROR_BAD_ARGUMENTS;
}
*p = *pin;
return HAL_OK;
}
hal_error_t hal_get_kek(uint8_t *kek,
size_t *kek_len,
const size_t kek_max)
{
if (kek == NULL || kek_len == NULL || kek_max < bitsToBytes(128))
return HAL_ERROR_BAD_ARGUMENTS;
if (kekbuf == NULL)
return HAL_ERROR_IMPOSSIBLE;
hal_error_t err;
const size_t len = ((kek_max < bitsToBytes(192)) ? bitsToBytes(128) :
(kek_max < bitsToBytes(256)) ? bitsToBytes(192) :
bitsToBytes(256));
uint8_t t = 0;
for (int i = 0; i < KEKBUF_LEN; i++)
t |= kekbuf[i];
if (t == 0 && (err = hal_rpc_get_random(kekbuf, sizeof(KEKBUF_LEN))) != HAL_OK)
return err;
memcpy(kek, kekbuf, len);
*kek_len = len;
return HAL_OK;
}
/*
* Local variables:
* indent-tabs-mode: nil
* End:
*/
|
