1 /** 2 * \file constant_flow.h 3 * 4 * \brief This file contains tools to ensure tested code has constant flow. 5 */ 6 7 /* 8 * Copyright The Mbed TLS Contributors 9 * SPDX-License-Identifier: Apache-2.0 10 * 11 * Licensed under the Apache License, Version 2.0 (the "License"); you may 12 * not use this file except in compliance with the License. 13 * You may obtain a copy of the License at 14 * 15 * http://www.apache.org/licenses/LICENSE-2.0 16 * 17 * Unless required by applicable law or agreed to in writing, software 18 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 19 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 20 * See the License for the specific language governing permissions and 21 * limitations under the License. 22 */ 23 24 #ifndef TEST_CONSTANT_FLOW_H 25 #define TEST_CONSTANT_FLOW_H 26 27 #include "mbedtls/build_info.h" 28 29 /* 30 * This file defines the two macros 31 * 32 * #define TEST_CF_SECRET(ptr, size) 33 * #define TEST_CF_PUBLIC(ptr, size) 34 * 35 * that can be used in tests to mark a memory area as secret (no branch or 36 * memory access should depend on it) or public (default, only needs to be 37 * marked explicitly when it was derived from secret data). 38 * 39 * Arguments: 40 * - ptr: a pointer to the memory area to be marked 41 * - size: the size in bytes of the memory area 42 * 43 * Implementation: 44 * The basic idea is that of ctgrind <https://github.com/agl/ctgrind>: we can 45 * re-use tools that were designed for checking use of uninitialized memory. 46 * This file contains two implementations: one based on MemorySanitizer, the 47 * other on valgrind's memcheck. If none of them is enabled, dummy macros that 48 * do nothing are defined for convenience. 49 * 50 * \note #TEST_CF_SECRET must be called directly from within a .function file, 51 * not indirectly via a macro defined under tests/include or a function 52 * under tests/src. This is because we only run Valgrind for constant 53 * flow on test suites that have greppable annotations inside them (see 54 * `skip_suites_without_constant_flow` in `tests/scripts/all.sh`). 55 */ 56 57 #if defined(MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN) 58 #include <sanitizer/msan_interface.h> 59 60 /* Use macros to avoid messing up with origin tracking */ 61 #define TEST_CF_SECRET __msan_allocated_memory 62 // void __msan_allocated_memory(const volatile void* data, size_t size); 63 #define TEST_CF_PUBLIC __msan_unpoison 64 // void __msan_unpoison(const volatile void *a, size_t size); 65 66 #elif defined(MBEDTLS_TEST_CONSTANT_FLOW_VALGRIND) 67 #include <valgrind/memcheck.h> 68 69 #define TEST_CF_SECRET VALGRIND_MAKE_MEM_UNDEFINED 70 // VALGRIND_MAKE_MEM_UNDEFINED(_qzz_addr, _qzz_len) 71 #define TEST_CF_PUBLIC VALGRIND_MAKE_MEM_DEFINED 72 // VALGRIND_MAKE_MEM_DEFINED(_qzz_addr, _qzz_len) 73 74 #else /* MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN || 75 MBEDTLS_TEST_CONSTANT_FLOW_VALGRIND */ 76 77 #define TEST_CF_SECRET(ptr, size) 78 #define TEST_CF_PUBLIC(ptr, size) 79 80 #endif /* MBEDTLS_TEST_CONSTANT_FLOW_MEMSAN || 81 MBEDTLS_TEST_CONSTANT_FLOW_VALGRIND */ 82 83 #endif /* TEST_CONSTANT_FLOW_H */ 84
