/**
* \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 (C) 2006-2018, Arm Limited (or its affiliates), All Rights Reserved
* SPDX-License-Identifier: GPL-2.0
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* This file is part of Mbed TLS (https://tls.mbed.org)
*/
#ifndef MBEDTLS_PLATFORM_H
#define MBEDTLS_PLATFORM_H
#if !defined(MBEDTLS_CONFIG_FILE)
#include "config.h"
#else
#include MBEDTLS_CONFIG_FILE
#endif
#if defined(MBEDTLS_HAVE_TIME)
#include "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 config.h or define them on the compiler command line.
* \{
*/
#if !defined(MBEDTLS_PLATFORM_NO_STD_FUNCTIONS)
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#if !defined(MBEDTLS_PLATFORM_STD_SNPRINTF)
#if defined(_WIN32)
#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_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(_WIN32)
/* 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 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 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 */