mbedtls/library/mps/common.h
Hanno Becker 75ac1f7b95 Add implementation for MPS assertion macros
Signed-off-by: Hanno Becker <hanno.becker@arm.com>
2021-03-29 14:19:32 +01:00

127 lines
4.1 KiB
C

/*
* 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.
*
* This file is part of mbed TLS (https://tls.mbed.org)
*/
/**
* \file common.h
*
* \brief Common functions and macros used by MPS
*/
#ifndef MBEDTLS_MPS_COMMON_H
#define MBEDTLS_MPS_COMMON_H
#include <stdio.h>
/**
* \name SECTION: MPS Configuration
*
* \{
*/
/*! This flag enables/disables assertions on the internal state of MPS.
*
* Assertions are sanity checks that should never trigger when MPS
* is used within the bounds of its API and preconditions.
*
* Enabling this increases security by limiting the scope of
* potential bugs, but comes at the cost of increased code size.
*
* Note: So far, there is no guiding principle as to what
* expected conditions merit an assertion, and which don't.
*
* Comment this to disable assertions.
*/
#define MBEDTLS_MPS_ENABLE_ASSERTIONS
/*! This flag controls whether tracing for MPS should be enabled. */
//#define MBEDTLS_MPS_TRACE
#if defined(MBEDTLS_MPS_ENABLE_ASSERTIONS)
#define MBEDTLS_MPS_ASSERT_RAW( cond, string ) \
do \
{ \
if( !(cond) ) \
{ \
TRACE( trace_error, string ); \
RETURN( MBEDTLS_ERR_MPS_INTERNAL_ERROR ); \
} \
} while( 0 )
#else /* MBEDTLS_MPS_ENABLE_ASSERTIONS */
#define MBEDTLS_MPS_ASSERT_RAW( cond, string ) do {} while( 0 )
#endif /* MBEDTLS_MPS_ENABLE_ASSERTIONS */
/* \} name SECTION: MPS Configuration */
/**
* \name SECTION: Common types
*
* Various common types used throughout MPS.
* \{
*/
/** \brief The type of buffer sizes and offsets used in MPS structures.
*
* This is an unsigned integer type that should be large enough to
* hold the length of any buffer resp. message processed by MPS.
*
* The reason to pick a value as small as possible here is
* to reduce the size of MPS structures.
*
* \warning Care has to be taken when using a narrower type
* than ::mbedtls_mps_size_t here because of
* potential truncation during conversion.
*
* \warning Handshake messages in TLS may be up to 2^24 ~ 16Mb in size.
* If mbedtls_mps_[opt_]stored_size_t is smaller than that, the
* maximum handshake message is restricted accordingly.
*
* For now, we use the default type of size_t throughout, and the use of
* smaller types or different types for ::mbedtls_mps_size_t and
* ::mbedtls_mps_stored_size_t is not yet supported.
*
*/
typedef size_t mbedtls_mps_stored_size_t;
#define MBEDTLS_MPS_SIZE_MAX ( (mbedtls_mps_size_t) -1 )
/** \brief The type of buffer sizes and offsets used in the MPS API
* and implementation.
*
* This must be at least as wide as ::mbedtls_stored_size_t but
* may be chosen to be strictly larger if more suitable for the
* target architecture.
*
* For example, in a test build for ARM Thumb, using uint_fast16_t
* instead of uint16_t reduced the code size from 1060 Byte to 962 Byte,
* so almost 10%.
*/
typedef size_t mbedtls_mps_size_t;
#if (mbedtls_mps_size_t) -1 > (mbedtls_mps_stored_size_t) -1
#error "Misconfiguration of mbedtls_mps_size_t and mbedtls_mps_stored_size_t."
#endif
/* \} SECTION: Common types */
#endif /* MBEDTLS_MPS_COMMON_H */