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
|
/* Copyright 2014 MongoDB Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the GNU Affero General Public License in all respects
* for all of the code used other than as permitted herein. If you modify
* file(s) with this exception, you may extend this exception to your
* version of the file(s), but you are not obligated to do so. If you do not
* wish to do so, delete this exception statement from your version. If you
* delete this exception statement from all source files in the program,
* then also delete it in the license file.
*/
#include "mongo/config.h"
#if defined(MONGO_CONFIG_HAVE_MEMSET_S)
#define __STDC_WANT_LIB_EXT1__ 1
#endif
#include "mongo/platform/basic.h"
#include <cstring>
#include "mongo/util/assert_util.h"
namespace mongo {
void secureZeroMemory(void* mem, size_t size) {
if (mem == nullptr) {
fassert(28751, size == 0);
return;
}
#if defined(_WIN32)
// Windows provides a simple function for zeroing memory
SecureZeroMemory(mem, size);
#elif defined(MONGO_CONFIG_HAVE_MEMSET_S)
// Some C11 libraries provide a variant of memset which is guaranteed to not be optimized away
fassert(28752, memset_s(mem, size, 0, size) == 0);
#else
// fall back to using volatile pointer
// using volatile to disable compiler optimizations
volatile char* p = reinterpret_cast<volatile char*>(mem); // NOLINT
while (size--) {
*p++ = 0;
}
#endif
}
} // namespace mongo
|
