blob: 277a85c7dfd931d00c9c1363d6d7df85aeeb5589 [file] [log] [blame]
/**
* \file platform.h
*
* \brief This file contains the definitions and functions of the
* Mbed TLS platform abstraction layer.
*
* The platform abstraction layer removes the need for the library
* to directly link to standard C library functions or operating
* system services, making the library easier to port and embed.
* Application developers and users of the library can provide their own
* implementations of these functions, or implementations specific to
* their platform, which can be statically linked to the library or
* dynamically configured at runtime.
*/
/*
* 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_PLATFORM_H
#define MBEDTLS_PLATFORM_H
#include "mbedtls/private_access.h"
#include "mbedtls/build_info.h"
#if defined(MBEDTLS_HAVE_TIME)
#include "mbedtls/platform_time.h"
#endif
#ifdef __cplusplus
extern "C" {
#endif
/**
* \name SECTION: Module settings
*
* The configuration options you can set for this module are in this section.
* Either change them in mbedtls_config.h or define them on the compiler command line.
* \{
*/
/* The older Microsoft Windows common runtime provides non-conforming
* implementations of some standard library functions, including snprintf
* and vsnprintf. This affects MSVC and MinGW builds.
*/
#if defined(__MINGW32__) || (defined(_MSC_VER) && _MSC_VER <= 1900)
#define MBEDTLS_PLATFORM_HAS_NON_CONFORMING_SNPRINTF
#define MBEDTLS_PLATFORM_HAS_NON_CONFORMING_VSNPRINTF
#endif
#if !defined(MBEDTLS_PLATFORM_NO_STD_FUNCTIONS)
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#if !defined(MBEDTLS_PLATFORM_STD_SNPRINTF)
#if defined(MBEDTLS_PLATFORM_HAS_NON_CONFORMING_SNPRINTF)
#define MBEDTLS_PLATFORM_STD_SNPRINTF mbedtls_platform_win32_snprintf /**< The default \c snprintf function to use. */
#else
#define MBEDTLS_PLATFORM_STD_SNPRINTF snprintf /**< The default \c snprintf function to use. */
#endif
#endif
#if !defined(MBEDTLS_PLATFORM_STD_VSNPRINTF)
#if defined(MBEDTLS_PLATFORM_HAS_NON_CONFORMING_VSNPRINTF)
#define MBEDTLS_PLATFORM_STD_VSNPRINTF mbedtls_platform_win32_vsnprintf /**< The default \c vsnprintf function to use. */
#else
#define MBEDTLS_PLATFORM_STD_VSNPRINTF vsnprintf /**< The default \c vsnprintf function to use. */
#endif
#endif
#if !defined(MBEDTLS_PLATFORM_STD_PRINTF)
#define MBEDTLS_PLATFORM_STD_PRINTF printf /**< The default \c printf function to use. */
#endif
#if !defined(MBEDTLS_PLATFORM_STD_FPRINTF)
#define MBEDTLS_PLATFORM_STD_FPRINTF fprintf /**< The default \c fprintf function to use. */
#endif
#if !defined(MBEDTLS_PLATFORM_STD_CALLOC)
#define MBEDTLS_PLATFORM_STD_CALLOC calloc /**< The default \c calloc function to use. */
#endif
#if !defined(MBEDTLS_PLATFORM_STD_FREE)
#define MBEDTLS_PLATFORM_STD_FREE free /**< The default \c free function to use. */
#endif
#if !defined(MBEDTLS_PLATFORM_STD_EXIT)
#define MBEDTLS_PLATFORM_STD_EXIT exit /**< The default \c exit function to use. */
#endif
#if !defined(MBEDTLS_PLATFORM_STD_TIME)
#define MBEDTLS_PLATFORM_STD_TIME time /**< The default \c time function to use. */
#endif
#if !defined(MBEDTLS_PLATFORM_STD_EXIT_SUCCESS)
#define MBEDTLS_PLATFORM_STD_EXIT_SUCCESS EXIT_SUCCESS /**< The default exit value to use. */
#endif
#if !defined(MBEDTLS_PLATFORM_STD_EXIT_FAILURE)
#define MBEDTLS_PLATFORM_STD_EXIT_FAILURE EXIT_FAILURE /**< The default exit value to use. */
#endif
#if defined(MBEDTLS_FS_IO)
#if !defined(MBEDTLS_PLATFORM_STD_NV_SEED_READ)
#define MBEDTLS_PLATFORM_STD_NV_SEED_READ mbedtls_platform_std_nv_seed_read
#endif
#if !defined(MBEDTLS_PLATFORM_STD_NV_SEED_WRITE)
#define MBEDTLS_PLATFORM_STD_NV_SEED_WRITE mbedtls_platform_std_nv_seed_write
#endif
#if !defined(MBEDTLS_PLATFORM_STD_NV_SEED_FILE)
#define MBEDTLS_PLATFORM_STD_NV_SEED_FILE "seedfile"
#endif
#endif /* MBEDTLS_FS_IO */
#else /* MBEDTLS_PLATFORM_NO_STD_FUNCTIONS */
#if defined(MBEDTLS_PLATFORM_STD_MEM_HDR)
#include MBEDTLS_PLATFORM_STD_MEM_HDR
#endif
#endif /* MBEDTLS_PLATFORM_NO_STD_FUNCTIONS */
/* \} name SECTION: Module settings */
/*
* The function pointers for calloc and free.
*/
#if defined(MBEDTLS_PLATFORM_MEMORY)
#if defined(MBEDTLS_PLATFORM_FREE_MACRO) && \
defined(MBEDTLS_PLATFORM_CALLOC_MACRO)
#define mbedtls_free MBEDTLS_PLATFORM_FREE_MACRO
#define mbedtls_calloc MBEDTLS_PLATFORM_CALLOC_MACRO
#else
/* For size_t */
#include <stddef.h>
extern void *mbedtls_calloc( size_t n, size_t size );
extern void mbedtls_free( void *ptr );
/**
* \brief This function dynamically sets the memory-management
* functions used by the library, during runtime.
*
* \param calloc_func The \c calloc function implementation.
* \param free_func The \c free function implementation.
*
* \return \c 0.
*/
int mbedtls_platform_set_calloc_free( void * (*calloc_func)( size_t, size_t ),
void (*free_func)( void * ) );
#endif /* MBEDTLS_PLATFORM_FREE_MACRO && MBEDTLS_PLATFORM_CALLOC_MACRO */
#else /* !MBEDTLS_PLATFORM_MEMORY */
#define mbedtls_free free
#define mbedtls_calloc calloc
#endif /* MBEDTLS_PLATFORM_MEMORY && !MBEDTLS_PLATFORM_{FREE,CALLOC}_MACRO */
/*
* The function pointers for fprintf
*/
#if defined(MBEDTLS_PLATFORM_FPRINTF_ALT)
/* We need FILE * */
#include <stdio.h>
extern int (*mbedtls_fprintf)( FILE *stream, const char *format, ... );
/**
* \brief This function dynamically configures the fprintf
* function that is called when the
* mbedtls_fprintf() function is invoked by the library.
*
* \param fprintf_func The \c fprintf function implementation.
*
* \return \c 0.
*/
int mbedtls_platform_set_fprintf( int (*fprintf_func)( FILE *stream, const char *,
... ) );
#else
#if defined(MBEDTLS_PLATFORM_FPRINTF_MACRO)
#define mbedtls_fprintf MBEDTLS_PLATFORM_FPRINTF_MACRO
#else
#define mbedtls_fprintf fprintf
#endif /* MBEDTLS_PLATFORM_FPRINTF_MACRO */
#endif /* MBEDTLS_PLATFORM_FPRINTF_ALT */
/*
* The function pointers for printf
*/
#if defined(MBEDTLS_PLATFORM_PRINTF_ALT)
extern int (*mbedtls_printf)( const char *format, ... );
/**
* \brief This function dynamically configures the snprintf
* function that is called when the mbedtls_snprintf()
* function is invoked by the library.
*
* \param printf_func The \c printf function implementation.
*
* \return \c 0 on success.
*/
int mbedtls_platform_set_printf( int (*printf_func)( const char *, ... ) );
#else /* !MBEDTLS_PLATFORM_PRINTF_ALT */
#if defined(MBEDTLS_PLATFORM_PRINTF_MACRO)
#define mbedtls_printf MBEDTLS_PLATFORM_PRINTF_MACRO
#else
#define mbedtls_printf printf
#endif /* MBEDTLS_PLATFORM_PRINTF_MACRO */
#endif /* MBEDTLS_PLATFORM_PRINTF_ALT */
/*
* The function pointers for snprintf
*
* The snprintf implementation should conform to C99:
* - it *must* always correctly zero-terminate the buffer
* (except when n == 0, then it must leave the buffer untouched)
* - however it is acceptable to return -1 instead of the required length when
* the destination buffer is too short.
*/
#if defined(MBEDTLS_PLATFORM_HAS_NON_CONFORMING_SNPRINTF)
/* For Windows (inc. MSYS2), we provide our own fixed implementation */
int mbedtls_platform_win32_snprintf( char *s, size_t n, const char *fmt, ... );
#endif
#if defined(MBEDTLS_PLATFORM_SNPRINTF_ALT)
extern int (*mbedtls_snprintf)( char * s, size_t n, const char * format, ... );
/**
* \brief This function allows configuring a custom
* \c snprintf function pointer.
*
* \param snprintf_func The \c snprintf function implementation.
*
* \return \c 0 on success.
*/
int mbedtls_platform_set_snprintf( int (*snprintf_func)( char * s, size_t n,
const char * format, ... ) );
#else /* MBEDTLS_PLATFORM_SNPRINTF_ALT */
#if defined(MBEDTLS_PLATFORM_SNPRINTF_MACRO)
#define mbedtls_snprintf MBEDTLS_PLATFORM_SNPRINTF_MACRO
#else
#define mbedtls_snprintf MBEDTLS_PLATFORM_STD_SNPRINTF
#endif /* MBEDTLS_PLATFORM_SNPRINTF_MACRO */
#endif /* MBEDTLS_PLATFORM_SNPRINTF_ALT */
/*
* The function pointers for vsnprintf
*
* The vsnprintf implementation should conform to C99:
* - it *must* always correctly zero-terminate the buffer
* (except when n == 0, then it must leave the buffer untouched)
* - however it is acceptable to return -1 instead of the required length when
* the destination buffer is too short.
*/
#if defined(MBEDTLS_PLATFORM_HAS_NON_CONFORMING_VSNPRINTF)
#include <stdarg.h>
/* For Older Windows (inc. MSYS2), we provide our own fixed implementation */
int mbedtls_platform_win32_vsnprintf( char *s, size_t n, const char *fmt, va_list arg );
#endif
#if defined(MBEDTLS_PLATFORM_VSNPRINTF_ALT)
#include <stdarg.h>
extern int (*mbedtls_vsnprintf)( char * s, size_t n, const char * format, va_list arg );
/**
* \brief Set your own snprintf function pointer
*
* \param vsnprintf_func The \c vsnprintf function implementation
*
* \return \c 0
*/
int mbedtls_platform_set_vsnprintf( int (*vsnprintf_func)( char * s, size_t n,
const char * format, va_list arg ) );
#else /* MBEDTLS_PLATFORM_VSNPRINTF_ALT */
#if defined(MBEDTLS_PLATFORM_VSNPRINTF_MACRO)
#define mbedtls_vsnprintf MBEDTLS_PLATFORM_VSNPRINTF_MACRO
#else
#define mbedtls_vsnprintf vsnprintf
#endif /* MBEDTLS_PLATFORM_VSNPRINTF_MACRO */
#endif /* MBEDTLS_PLATFORM_VSNPRINTF_ALT */
/*
* The function pointers for exit
*/
#if defined(MBEDTLS_PLATFORM_EXIT_ALT)
extern void (*mbedtls_exit)( int status );
/**
* \brief This function dynamically configures the exit
* function that is called when the mbedtls_exit()
* function is invoked by the library.
*
* \param exit_func The \c exit function implementation.
*
* \return \c 0 on success.
*/
int mbedtls_platform_set_exit( void (*exit_func)( int status ) );
#else
#if defined(MBEDTLS_PLATFORM_EXIT_MACRO)
#define mbedtls_exit MBEDTLS_PLATFORM_EXIT_MACRO
#else
#define mbedtls_exit exit
#endif /* MBEDTLS_PLATFORM_EXIT_MACRO */
#endif /* MBEDTLS_PLATFORM_EXIT_ALT */
/*
* The default exit values
*/
#if defined(MBEDTLS_PLATFORM_STD_EXIT_SUCCESS)
#define MBEDTLS_EXIT_SUCCESS MBEDTLS_PLATFORM_STD_EXIT_SUCCESS
#else
#define MBEDTLS_EXIT_SUCCESS 0
#endif
#if defined(MBEDTLS_PLATFORM_STD_EXIT_FAILURE)
#define MBEDTLS_EXIT_FAILURE MBEDTLS_PLATFORM_STD_EXIT_FAILURE
#else
#define MBEDTLS_EXIT_FAILURE 1
#endif
/*
* The function pointers for reading from and writing a seed file to
* Non-Volatile storage (NV) in a platform-independent way
*
* Only enabled when the NV seed entropy source is enabled
*/
#if defined(MBEDTLS_ENTROPY_NV_SEED)
#if !defined(MBEDTLS_PLATFORM_NO_STD_FUNCTIONS) && defined(MBEDTLS_FS_IO)
/* Internal standard platform definitions */
int mbedtls_platform_std_nv_seed_read( unsigned char *buf, size_t buf_len );
int mbedtls_platform_std_nv_seed_write( unsigned char *buf, size_t buf_len );
#endif
#if defined(MBEDTLS_PLATFORM_NV_SEED_ALT)
extern int (*mbedtls_nv_seed_read)( unsigned char *buf, size_t buf_len );
extern int (*mbedtls_nv_seed_write)( unsigned char *buf, size_t buf_len );
/**
* \brief This function allows configuring custom seed file writing and
* reading functions.
*
* \param nv_seed_read_func The seed reading function implementation.
* \param nv_seed_write_func The seed writing function implementation.
*
* \return \c 0 on success.
*/
int mbedtls_platform_set_nv_seed(
int (*nv_seed_read_func)( unsigned char *buf, size_t buf_len ),
int (*nv_seed_write_func)( unsigned char *buf, size_t buf_len )
);
#else
#if defined(MBEDTLS_PLATFORM_NV_SEED_READ_MACRO) && \
defined(MBEDTLS_PLATFORM_NV_SEED_WRITE_MACRO)
#define mbedtls_nv_seed_read MBEDTLS_PLATFORM_NV_SEED_READ_MACRO
#define mbedtls_nv_seed_write MBEDTLS_PLATFORM_NV_SEED_WRITE_MACRO
#else
#define mbedtls_nv_seed_read mbedtls_platform_std_nv_seed_read
#define mbedtls_nv_seed_write mbedtls_platform_std_nv_seed_write
#endif
#endif /* MBEDTLS_PLATFORM_NV_SEED_ALT */
#endif /* MBEDTLS_ENTROPY_NV_SEED */
#if !defined(MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT)
/**
* \brief The platform context structure.
*
* \note This structure may be used to assist platform-specific
* setup or teardown operations.
*/
typedef struct mbedtls_platform_context
{
char MBEDTLS_PRIVATE(dummy); /**< A placeholder member, as empty structs are not portable. */
}
mbedtls_platform_context;
#else
#include "platform_alt.h"
#endif /* !MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT */
/**
* \brief This function performs any platform-specific initialization
* operations.
*
* \note This function should be called before any other library functions.
*
* Its implementation is platform-specific, and unless
* platform-specific code is provided, it does nothing.
*
* \note The usage and necessity of this function is dependent on the platform.
*
* \param ctx The platform context.
*
* \return \c 0 on success.
*/
int mbedtls_platform_setup( mbedtls_platform_context *ctx );
/**
* \brief This function performs any platform teardown operations.
*
* \note This function should be called after every other Mbed TLS module
* has been correctly freed using the appropriate free function.
*
* Its implementation is platform-specific, and unless
* platform-specific code is provided, it does nothing.
*
* \note The usage and necessity of this function is dependent on the platform.
*
* \param ctx The platform context.
*
*/
void mbedtls_platform_teardown( mbedtls_platform_context *ctx );
#ifdef __cplusplus
}
#endif
#endif /* platform.h */