| 1 | /** |
| 2 | * \file platform_util.h |
| 3 | * |
| 4 | * \brief Common and shared functions used by multiple modules in the Mbed TLS |
| 5 | * library. |
| 6 | */ |
| 7 | /* |
| 8 | * Copyright (C) 2018, Arm Limited, All Rights Reserved |
| 9 | * SPDX-License-Identifier: GPL-2.0 |
| 10 | * |
| 11 | * This program is free software; you can redistribute it and/or modify |
| 12 | * it under the terms of the GNU General Public License as published by |
| 13 | * the Free Software Foundation; either version 2 of the License, or |
| 14 | * (at your option) any later version. |
| 15 | * |
| 16 | * This program is distributed in the hope that it will be useful, |
| 17 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 18 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 19 | * GNU General Public License for more details. |
| 20 | * |
| 21 | * You should have received a copy of the GNU General Public License along |
| 22 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 23 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 24 | * |
| 25 | * This file is part of Mbed TLS (https://tls.mbed.org) |
| 26 | */ |
| 27 | #ifndef MBEDTLS_PLATFORM_UTIL_H |
| 28 | #define MBEDTLS_PLATFORM_UTIL_H |
| 29 | |
| 30 | #include <stddef.h> |
| 31 | |
| 32 | #ifdef __cplusplus |
| 33 | extern "C" { |
| 34 | #endif |
| 35 | |
| 36 | /** |
| 37 | * \brief Securely zeroize a buffer |
| 38 | * |
| 39 | * The function is meant to wipe the data contained in a buffer so |
| 40 | * that it can no longer be recovered even if the program memory |
| 41 | * is later compromised. Call this function on sensitive data |
| 42 | * stored on the stack before returning from a function, and on |
| 43 | * sensitive data stored on the heap before freeing the heap |
| 44 | * object. |
| 45 | * |
| 46 | * It is extremely difficult to guarantee that calls to |
| 47 | * mbedtls_platform_zeroize() are not removed by aggressive |
| 48 | * compiler optimizations in a portable way. For this reason, Mbed |
| 49 | * TLS provides the configuration option |
| 50 | * MBEDTLS_PLATFORM_ZEROIZE_ALT, which allows users to configure |
| 51 | * mbedtls_platform_zeroize() to use a suitable implementation for |
| 52 | * their platform and needs |
| 53 | * |
| 54 | * \param buf Buffer to be zeroized |
| 55 | * \param len Length of the buffer in bytes |
| 56 | * |
| 57 | */ |
| 58 | void mbedtls_platform_zeroize( void *buf, size_t len ); |
| 59 | |
| 60 | #ifdef __cplusplus |
| 61 | } |
| 62 | #endif |
| 63 | |
| 64 | #endif /* MBEDTLS_PLATFORM_UTIL_H */ |