Janos Follath | 96cfd7a | 2024-08-22 18:30:06 +0100 | [diff] [blame] | 1 | /** Support for path tracking in optionally safe bignum functions |
| 2 | * |
| 3 | * The functions are called when an optionally safe path is taken and logs it with a single |
| 4 | * variable. This variable is at any time in one of three states: |
| 5 | * - MBEDTLS_MPI_IS_TEST: No optionally safe path has been taken since the last reset |
| 6 | * - MBEDTLS_MPI_IS_SECRET: Only safe paths were teken since the last reset |
| 7 | * - MBEDTLS_MPI_IS_PUBLIC: At least one unsafe path has been taken since the last reset |
| 8 | * |
| 9 | * Using a simple global variable to track execution path. Making it work with multithreading |
| 10 | * doesn't worth the effort as multithreaded tests add little to no value here. |
| 11 | */ |
| 12 | /* |
| 13 | * Copyright The Mbed TLS Contributors |
| 14 | * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later |
| 15 | */ |
| 16 | |
| 17 | #ifndef BIGNUM_CODEPATH_CHECK_H |
| 18 | #define BIGNUM_CODEPATH_CHECK_H |
| 19 | |
| 20 | #include "bignum_core.h" |
| 21 | |
| 22 | #if defined(MBEDTLS_TEST_HOOKS) && !defined(MBEDTLS_THREADING_C) |
| 23 | |
| 24 | extern int mbedtls_codepath_check; |
| 25 | |
| 26 | /** |
| 27 | * \brief Setup the codepath test hooks used by optionally safe bignum functions to signal |
| 28 | * the path taken. |
| 29 | */ |
| 30 | void mbedtls_codepath_test_hooks_setup(void); |
| 31 | |
| 32 | /** |
| 33 | * \brief Teardown the codepath test hooks used by optionally safe bignum functions to |
| 34 | * signal the path taken. |
| 35 | */ |
| 36 | void mbedtls_codepath_test_hooks_teardown(void); |
| 37 | |
| 38 | /** |
| 39 | * \brief Reset the state of the codepath to the initial state. |
| 40 | */ |
| 41 | static inline void mbedtls_codepath_reset(void) |
| 42 | { |
| 43 | mbedtls_codepath_check = MBEDTLS_MPI_IS_TEST; |
| 44 | } |
| 45 | |
| 46 | #endif /* MBEDTLS_TEST_HOOKS && !MBEDTLS_THREADING_C */ |
| 47 | |
| 48 | #endif /* BIGNUM_CODEPATH_CHECK_H */ |