198 lines
6.5 KiB
C
198 lines
6.5 KiB
C
/**
|
|
* \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>
|
|
|
|
#if defined(__ARM_NEON)
|
|
#include <arm_neon.h>
|
|
#endif /* __ARM_NEON */
|
|
|
|
/** 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)
|
|
#if defined(__ARM_NEON)
|
|
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);
|
|
}
|
|
#elif defined(__amd64__) || defined(__x86_64__) || defined(__aarch64__)
|
|
/* 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);
|
|
}
|
|
#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);
|
|
}
|
|
#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
|
|
#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
|
|
|
|
/* Define compiler branch hints */
|
|
#if defined(__has_builtin)
|
|
#if __has_builtin(__builtin_expect)
|
|
#define MBEDTLS_LIKELY(x) __builtin_expect((x), 1)
|
|
#define MBEDTLS_UNLIKELY(x) __builtin_expect((x), 0)
|
|
#endif
|
|
#endif
|
|
#if !defined(MBEDTLS_LIKELY)
|
|
#define MBEDTLS_LIKELY(x) x
|
|
#define MBEDTLS_UNLIKELY(x) x
|
|
#endif
|
|
|
|
#endif /* MBEDTLS_LIBRARY_COMMON_H */
|