| /** |
| * \file common.h |
| * |
| * \brief Utility macros for internal use in the library |
| */ |
| /* |
| * Copyright The Mbed TLS Contributors |
| * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later |
| */ |
| |
| #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> |
| |
| #if defined(__ARM_NEON) |
| #include <arm_neon.h> |
| #define MBEDTLS_HAVE_NEON_INTRINSICS |
| #elif defined(MBEDTLS_PLATFORM_IS_WINDOWS_ON_ARM64) |
| #include <arm64_neon.h> |
| #define MBEDTLS_HAVE_NEON_INTRINSICS |
| #endif |
| |
| /** 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) */ |
| |
| /** \def ARRAY_LENGTH |
| * Return the number of elements of a static or stack array. |
| * |
| * \param array A value of array (not pointer) type. |
| * |
| * \return The number of elements of the array. |
| */ |
| /* A correct implementation of ARRAY_LENGTH, but which silently gives |
| * a nonsensical result if called with a pointer rather than an array. */ |
| #define ARRAY_LENGTH_UNSAFE(array) \ |
| (sizeof(array) / sizeof(*(array))) |
| |
| #if defined(__GNUC__) |
| /* Test if arg and &(arg)[0] have the same type. This is true if arg is |
| * an array but not if it's a pointer. */ |
| #define IS_ARRAY_NOT_POINTER(arg) \ |
| (!__builtin_types_compatible_p(__typeof__(arg), \ |
| __typeof__(&(arg)[0]))) |
| /* A compile-time constant with the value 0. If `const_expr` is not a |
| * compile-time constant with a nonzero value, cause a compile-time error. */ |
| #define STATIC_ASSERT_EXPR(const_expr) \ |
| (0 && sizeof(struct { unsigned int STATIC_ASSERT : 1 - 2 * !(const_expr); })) |
| |
| /* Return the scalar value `value` (possibly promoted). This is a compile-time |
| * constant if `value` is. `condition` must be a compile-time constant. |
| * If `condition` is false, arrange to cause a compile-time error. */ |
| #define STATIC_ASSERT_THEN_RETURN(condition, value) \ |
| (STATIC_ASSERT_EXPR(condition) ? 0 : (value)) |
| |
| #define ARRAY_LENGTH(array) \ |
| (STATIC_ASSERT_THEN_RETURN(IS_ARRAY_NOT_POINTER(array), \ |
| ARRAY_LENGTH_UNSAFE(array))) |
| |
| #else |
| /* If we aren't sure the compiler supports our non-standard tricks, |
| * fall back to the unsafe implementation. */ |
| #define ARRAY_LENGTH(array) ARRAY_LENGTH_UNSAFE(array) |
| #endif |
| /** 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 |
| |
| /** |
| * \brief Securely zeroize a buffer then free it. |
| * |
| * Similar to making consecutive calls to |
| * \c mbedtls_platform_zeroize() and \c mbedtls_free(), but has |
| * code size savings, and potential for optimisation in the future. |
| * |
| * Guaranteed to be a no-op if \p buf is \c NULL and \p len is 0. |
| * |
| * \param buf Buffer to be zeroized then freed. |
| * \param len Length of the buffer in bytes |
| */ |
| void mbedtls_zeroize_and_free(void *buf, size_t len); |
| |
| /** 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; |
| } |
| |
| /* Always inline mbedtls_xor() for similar reasons as mbedtls_xor_no_simd(). */ |
| #if defined(__IAR_SYSTEMS_ICC__) |
| #pragma inline = forced |
| #elif defined(__GNUC__) |
| __attribute__((always_inline)) |
| #endif |
| /** |
| * 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. |
| * |
| * \note Depending on the situation, it may be faster to use either mbedtls_xor() or |
| * mbedtls_xor_no_simd() (these are functionally equivalent). |
| * If the result is used immediately after the xor operation in non-SIMD code (e.g, in |
| * AES-CBC), there may be additional latency to transfer the data from SIMD to scalar |
| * registers, and in this case, mbedtls_xor_no_simd() may be faster. In other cases where |
| * the result is not used immediately (e.g., in AES-CTR), mbedtls_xor() may be faster. |
| * For targets without SIMD support, they will behave the same. |
| */ |
| static 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) |
| #if defined(MBEDTLS_HAVE_NEON_INTRINSICS) && \ |
| (!(defined(MBEDTLS_COMPILER_IS_GCC) && MBEDTLS_GCC_VERSION < 70300)) |
| /* Old GCC versions generate a warning here, so disable the NEON path for these compilers */ |
| for (; (i + 16) <= n; i += 16) { |
| uint8x16_t v1 = vld1q_u8(a + i); |
| uint8x16_t v2 = vld1q_u8(b + i); |
| uint8x16_t x = veorq_u8(v1, v2); |
| vst1q_u8(r + i, x); |
| } |
| #if defined(__IAR_SYSTEMS_ICC__) |
| /* This if statement helps some compilers (e.g., IAR) optimise out the byte-by-byte tail case |
| * where n is a constant multiple of 16. |
| * For other compilers (e.g. recent gcc and clang) it makes no difference if n is a compile-time |
| * constant, and is a very small perf regression if n is not a compile-time constant. */ |
| if (n % 16 == 0) { |
| return; |
| } |
| #endif |
| #elif defined(MBEDTLS_ARCH_IS_X64) || defined(MBEDTLS_ARCH_IS_ARM64) |
| /* This codepath probably only makes sense on architectures with 64-bit registers */ |
| for (; (i + 8) <= n; i += 8) { |
| uint64_t x = mbedtls_get_unaligned_uint64(a + i) ^ mbedtls_get_unaligned_uint64(b + i); |
| mbedtls_put_unaligned_uint64(r + i, x); |
| } |
| #if defined(__IAR_SYSTEMS_ICC__) |
| if (n % 8 == 0) { |
| return; |
| } |
| #endif |
| #else |
| 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); |
| } |
| #if defined(__IAR_SYSTEMS_ICC__) |
| if (n % 4 == 0) { |
| return; |
| } |
| #endif |
| #endif |
| #endif |
| for (; i < n; i++) { |
| r[i] = a[i] ^ b[i]; |
| } |
| } |
| |
| /* Always inline mbedtls_xor_no_simd() as we see significant perf regressions when it does not get |
| * inlined (e.g., observed about 3x perf difference in gcm_mult_largetable with gcc 7 - 12) */ |
| #if defined(__IAR_SYSTEMS_ICC__) |
| #pragma inline = forced |
| #elif defined(__GNUC__) |
| __attribute__((always_inline)) |
| #endif |
| /** |
| * Perform a fast block XOR operation, such that |
| * r[i] = a[i] ^ b[i] where 0 <= i < n |
| * |
| * In some situations, this can perform better than mbedtls_xor() (e.g., it's about 5% |
| * better in AES-CBC). |
| * |
| * \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. |
| * |
| * \note Depending on the situation, it may be faster to use either mbedtls_xor() or |
| * mbedtls_xor_no_simd() (these are functionally equivalent). |
| * If the result is used immediately after the xor operation in non-SIMD code (e.g, in |
| * AES-CBC), there may be additional latency to transfer the data from SIMD to scalar |
| * registers, and in this case, mbedtls_xor_no_simd() may be faster. In other cases where |
| * the result is not used immediately (e.g., in AES-CTR), mbedtls_xor() may be faster. |
| * For targets without SIMD support, they will behave the same. |
| */ |
| static inline void mbedtls_xor_no_simd(unsigned char *r, |
| const unsigned char *a, |
| const unsigned char *b, |
| size_t n) |
| { |
| size_t i = 0; |
| #if defined(MBEDTLS_EFFICIENT_UNALIGNED_ACCESS) |
| #if defined(MBEDTLS_ARCH_IS_X64) || defined(MBEDTLS_ARCH_IS_ARM64) |
| /* This codepath probably only makes sense on architectures with 64-bit registers */ |
| for (; (i + 8) <= n; i += 8) { |
| uint64_t x = mbedtls_get_unaligned_uint64(a + i) ^ mbedtls_get_unaligned_uint64(b + i); |
| mbedtls_put_unaligned_uint64(r + i, x); |
| } |
| #if defined(__IAR_SYSTEMS_ICC__) |
| /* This if statement helps some compilers (e.g., IAR) optimise out the byte-by-byte tail case |
| * where n is a constant multiple of 8. |
| * For other compilers (e.g. recent gcc and clang) it makes no difference if n is a compile-time |
| * constant, and is a very small perf regression if n is not a compile-time constant. */ |
| if (n % 8 == 0) { |
| return; |
| } |
| #endif |
| #else |
| 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); |
| } |
| #if defined(__IAR_SYSTEMS_ICC__) |
| if (n % 4 == 0) { |
| return; |
| } |
| #endif |
| #endif |
| #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 |
| #if defined(__IAR_SYSTEMS_ICC__) |
| #define asm __asm |
| #else |
| #define asm __asm__ |
| #endif |
| #endif |
| /* *INDENT-ON* */ |
| |
| /* |
| * Define the constraint used for read-only pointer operands to aarch64 asm. |
| * |
| * This is normally the usual "r", but for aarch64_32 (aka ILP32, |
| * as found in watchos), "p" is required to avoid warnings from clang. |
| * |
| * Note that clang does not recognise '+p' or '=p', and armclang |
| * does not recognise 'p' at all. Therefore, to update a pointer from |
| * aarch64 assembly, it is necessary to use something like: |
| * |
| * uintptr_t uptr = (uintptr_t) ptr; |
| * asm( "ldr x4, [%x0], #8" ... : "+r" (uptr) : : ) |
| * ptr = (void*) uptr; |
| * |
| * Note that the "x" in "%x0" is neccessary; writing "%0" will cause warnings. |
| */ |
| #if defined(__aarch64__) && defined(MBEDTLS_HAVE_ASM) |
| #if UINTPTR_MAX == 0xfffffffful |
| /* ILP32: Specify the pointer operand slightly differently, as per #7787. */ |
| #define MBEDTLS_ASM_AARCH64_PTR_CONSTRAINT "p" |
| #elif UINTPTR_MAX == 0xfffffffffffffffful |
| /* Normal case (64-bit pointers): use "r" as the constraint for pointer operands to asm */ |
| #define MBEDTLS_ASM_AARCH64_PTR_CONSTRAINT "r" |
| #else |
| #error "Unrecognised pointer size for aarch64" |
| #endif |
| #endif |
| |
| /* 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 |
| |
| #if defined(__has_builtin) |
| #define MBEDTLS_HAS_BUILTIN(x) __has_builtin(x) |
| #else |
| #define MBEDTLS_HAS_BUILTIN(x) 0 |
| #endif |
| |
| /* Define compiler branch hints */ |
| #if MBEDTLS_HAS_BUILTIN(__builtin_expect) |
| #define MBEDTLS_LIKELY(x) __builtin_expect(!!(x), 1) |
| #define MBEDTLS_UNLIKELY(x) __builtin_expect(!!(x), 0) |
| #else |
| #define MBEDTLS_LIKELY(x) x |
| #define MBEDTLS_UNLIKELY(x) x |
| #endif |
| |
| /* MBEDTLS_ASSUME may be used to provide additional information to the compiler |
| * which can result in smaller code-size. */ |
| #if MBEDTLS_HAS_BUILTIN(__builtin_assume) |
| /* clang provides __builtin_assume */ |
| #define MBEDTLS_ASSUME(x) __builtin_assume(x) |
| #elif MBEDTLS_HAS_BUILTIN(__builtin_unreachable) |
| /* gcc and IAR can use __builtin_unreachable */ |
| #define MBEDTLS_ASSUME(x) do { if (!(x)) __builtin_unreachable(); } while (0) |
| #elif defined(_MSC_VER) |
| /* Supported by MSVC since VS 2005 */ |
| #define MBEDTLS_ASSUME(x) __assume(x) |
| #else |
| #define MBEDTLS_ASSUME(x) do { } while (0) |
| #endif |
| |
| /* For gcc -Os, override with -O2 for a given function. |
| * |
| * This will not affect behaviour for other optimisation settings, e.g. -O0. |
| */ |
| #if defined(MBEDTLS_COMPILER_IS_GCC) && defined(__OPTIMIZE_SIZE__) |
| #define MBEDTLS_OPTIMIZE_FOR_PERFORMANCE __attribute__((optimize("-O2"))) |
| #else |
| #define MBEDTLS_OPTIMIZE_FOR_PERFORMANCE |
| #endif |
| |
| /* Suppress compiler warnings for unused functions and variables. */ |
| #if !defined(MBEDTLS_MAYBE_UNUSED) && defined(__has_attribute) |
| # if __has_attribute(unused) |
| # define MBEDTLS_MAYBE_UNUSED __attribute__((unused)) |
| # endif |
| #endif |
| #if !defined(MBEDTLS_MAYBE_UNUSED) && defined(__GNUC__) |
| # define MBEDTLS_MAYBE_UNUSED __attribute__((unused)) |
| #endif |
| #if !defined(MBEDTLS_MAYBE_UNUSED) && defined(__IAR_SYSTEMS_ICC__) && defined(__VER__) |
| /* IAR does support __attribute__((unused)), but only if the -e flag (extended language support) |
| * is given; the pragma always works. |
| * Unfortunately the pragma affects the rest of the file where it is used, but this is harmless. |
| * Check for version 5.2 or later - this pragma may be supported by earlier versions, but I wasn't |
| * able to find documentation). |
| */ |
| # if (__VER__ >= 5020000) |
| # define MBEDTLS_MAYBE_UNUSED _Pragma("diag_suppress=Pe177") |
| # endif |
| #endif |
| #if !defined(MBEDTLS_MAYBE_UNUSED) && defined(_MSC_VER) |
| # define MBEDTLS_MAYBE_UNUSED __pragma(warning(suppress:4189)) |
| #endif |
| #if !defined(MBEDTLS_MAYBE_UNUSED) |
| # define MBEDTLS_MAYBE_UNUSED |
| #endif |
| |
| #endif /* MBEDTLS_LIBRARY_COMMON_H */ |