/** * \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 #include #include #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 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 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 */