mirror of
https://github.com/mollyim/webrtc.git
synced 2025-05-12 21:30:45 +01:00
5b32f238f3
The previously used "memset(ptr, 0, size)" can get optimized away by compilers if "ptr" is not used afterwards. A new class "ZeroOnFreeBuffer" is introduced that can hold sensitive data and that automatically clears underlying memory when it's no longer used. Bug: webrtc:8806, webrtc:8897, webrtc:8905 Change-Id: Iedddddf80790f9af0addaab3346ec5bff102917d Reviewed-on: https://webrtc-review.googlesource.com/41941 Commit-Queue: Joachim Bauch <jbauch@webrtc.org> Reviewed-by: Karl Wiberg <kwiberg@webrtc.org> Cr-Commit-Position: refs/heads/master@{#22334}
38 lines
1.1 KiB
C++
38 lines
1.1 KiB
C++
/*
|
|
* Copyright 2017 The WebRTC Project Authors. All rights reserved.
|
|
*
|
|
* Use of this source code is governed by a BSD-style license
|
|
* that can be found in the LICENSE file in the root of the source
|
|
* tree. An additional intellectual property rights grant can be found
|
|
* in the file PATENTS. All contributing project authors may
|
|
* be found in the AUTHORS file in the root of the source tree.
|
|
*/
|
|
|
|
#if defined(WEBRTC_WIN)
|
|
#include <windows.h>
|
|
#else
|
|
#include <string.h>
|
|
#endif
|
|
|
|
#include "rtc_base/checks.h"
|
|
#include "rtc_base/zero_memory.h"
|
|
|
|
namespace rtc {
|
|
|
|
// Code and comment taken from "OPENSSL_cleanse" of BoringSSL.
|
|
void ExplicitZeroMemory(void* ptr, size_t len) {
|
|
RTC_DCHECK(ptr || !len);
|
|
#if defined(WEBRTC_WIN)
|
|
SecureZeroMemory(ptr, len);
|
|
#else
|
|
memset(ptr, 0, len);
|
|
#if !defined(__pnacl__)
|
|
/* As best as we can tell, this is sufficient to break any optimisations that
|
|
might try to eliminate "superfluous" memsets. If there's an easy way to
|
|
detect memset_s, it would be better to use that. */
|
|
__asm__ __volatile__("" : : "r"(ptr) : "memory"); // NOLINT
|
|
#endif
|
|
#endif // !WEBRTC_WIN
|
|
}
|
|
|
|
} // namespace rtc
|