| /** |
| * \file common.h |
| * |
| * \brief Utility macros for internal use in the library |
| */ |
| /* |
| * Copyright The Mbed TLS Contributors |
| * SPDX-License-Identifier: Apache-2.0 |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); you may |
| * not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #ifndef MBEDTLS_LIBRARY_COMMON_H |
| #define MBEDTLS_LIBRARY_COMMON_H |
| |
| #include "mbedtls/build_info.h" |
| #include "alignment.h" |
| |
| #include <assert.h> |
| #include <stddef.h> |
| #include <stdint.h> |
| #include <stddef.h> |
| |
| /** Helper to define a function as static except when building invasive tests. |
| * |
| * If a function is only used inside its own source file and should be |
| * declared `static` to allow the compiler to optimize for code size, |
| * but that function has unit tests, define it with |
| * ``` |
| * MBEDTLS_STATIC_TESTABLE int mbedtls_foo(...) { ... } |
| * ``` |
| * and declare it in a header in the `library/` directory with |
| * ``` |
| * #if defined(MBEDTLS_TEST_HOOKS) |
| * int mbedtls_foo(...); |
| * #endif |
| * ``` |
| */ |
| #if defined(MBEDTLS_TEST_HOOKS) |
| #define MBEDTLS_STATIC_TESTABLE |
| #else |
| #define MBEDTLS_STATIC_TESTABLE static |
| #endif |
| |
| #if defined(MBEDTLS_TEST_HOOKS) |
| extern void (*mbedtls_test_hook_test_fail)(const char *test, int line, const char *file); |
| #define MBEDTLS_TEST_HOOK_TEST_ASSERT(TEST) \ |
| do { \ |
| if ((!(TEST)) && ((*mbedtls_test_hook_test_fail) != NULL)) \ |
| { \ |
| (*mbedtls_test_hook_test_fail)( #TEST, __LINE__, __FILE__); \ |
| } \ |
| } while (0) |
| #else |
| #define MBEDTLS_TEST_HOOK_TEST_ASSERT(TEST) |
| #endif /* defined(MBEDTLS_TEST_HOOKS) */ |
| |
| /** Allow library to access its structs' private members. |
| * |
| * Although structs defined in header files are publicly available, |
| * their members are private and should not be accessed by the user. |
| */ |
| #define MBEDTLS_ALLOW_PRIVATE_ACCESS |
| |
| /** Return an offset into a buffer. |
| * |
| * This is just the addition of an offset to a pointer, except that this |
| * function also accepts an offset of 0 into a buffer whose pointer is null. |
| * (`p + n` has undefined behavior when `p` is null, even when `n == 0`. |
| * A null pointer is a valid buffer pointer when the size is 0, for example |
| * as the result of `malloc(0)` on some platforms.) |
| * |
| * \param p Pointer to a buffer of at least n bytes. |
| * This may be \p NULL if \p n is zero. |
| * \param n An offset in bytes. |
| * \return Pointer to offset \p n in the buffer \p p. |
| * Note that this is only a valid pointer if the size of the |
| * buffer is at least \p n + 1. |
| */ |
| static inline unsigned char *mbedtls_buffer_offset( |
| unsigned char *p, size_t n) |
| { |
| return p == NULL ? NULL : p + n; |
| } |
| |
| /** Return an offset into a read-only buffer. |
| * |
| * Similar to mbedtls_buffer_offset(), but for const pointers. |
| * |
| * \param p Pointer to a buffer of at least n bytes. |
| * This may be \p NULL if \p n is zero. |
| * \param n An offset in bytes. |
| * \return Pointer to offset \p n in the buffer \p p. |
| * Note that this is only a valid pointer if the size of the |
| * buffer is at least \p n + 1. |
| */ |
| static inline const unsigned char *mbedtls_buffer_offset_const( |
| const unsigned char *p, size_t n) |
| { |
| return p == NULL ? NULL : p + n; |
| } |
| |
| /** |
| * Perform a fast block XOR operation, such that |
| * r[i] = a[i] ^ b[i] where 0 <= i < n |
| * |
| * \param r Pointer to result (buffer of at least \p n bytes). \p r |
| * may be equal to either \p a or \p b, but behaviour when |
| * it overlaps in other ways is undefined. |
| * \param a Pointer to input (buffer of at least \p n bytes) |
| * \param b Pointer to input (buffer of at least \p n bytes) |
| * \param n Number of bytes to process. |
| */ |
| inline void mbedtls_xor(unsigned char *r, const unsigned char *a, const unsigned char *b, size_t n) |
| { |
| size_t i = 0; |
| #if defined(MBEDTLS_EFFICIENT_UNALIGNED_ACCESS) |
| for (; (i + 4) <= n; i += 4) { |
| uint32_t x = mbedtls_get_unaligned_uint32(a + i) ^ mbedtls_get_unaligned_uint32(b + i); |
| mbedtls_put_unaligned_uint32(r + i, x); |
| } |
| #endif |
| for (; i < n; i++) { |
| r[i] = a[i] ^ b[i]; |
| } |
| } |
| |
| /* Fix MSVC C99 compatible issue |
| * MSVC support __func__ from visual studio 2015( 1900 ) |
| * Use MSVC predefine macro to avoid name check fail. |
| */ |
| #if (defined(_MSC_VER) && (_MSC_VER <= 1900)) |
| #define /*no-check-names*/ __func__ __FUNCTION__ |
| #endif |
| |
| /* Define `asm` for compilers which don't define it. */ |
| /* *INDENT-OFF* */ |
| #ifndef asm |
| #define asm __asm__ |
| #endif |
| /* *INDENT-ON* */ |
| |
| /* Always provide a static assert macro, so it can be used unconditionally. |
| * It will expand to nothing on some systems. |
| * Can be used outside functions (but don't add a trailing ';' in that case: |
| * the semicolon is included here to avoid triggering -Wextra-semi when |
| * MBEDTLS_STATIC_ASSERT() expands to nothing). |
| * Can't use the C11-style `defined(static_assert)` on FreeBSD, since it |
| * defines static_assert even with -std=c99, but then complains about it. |
| */ |
| #if defined(static_assert) && !defined(__FreeBSD__) |
| #define MBEDTLS_STATIC_ASSERT(expr, msg) static_assert(expr, msg); |
| #else |
| #define MBEDTLS_STATIC_ASSERT(expr, msg) |
| #endif |
| |
| #endif /* MBEDTLS_LIBRARY_COMMON_H */ |