| 1 | /** |
| 2 | * \file platform.h |
| 3 | * |
| 4 | * \brief This file contains the definitions and functions of the |
| 5 | * Mbed TLS platform abstraction layer. |
| 6 | * |
| 7 | * The platform abstraction layer removes the need for the library |
| 8 | * to directly link to standard C library functions or operating |
| 9 | * system services, making the library easier to port and embed. |
| 10 | * Application developers and users of the library can provide their own |
| 11 | * implementations of these functions, or implementations specific to |
| 12 | * their platform, which can be statically linked to the library or |
| 13 | * dynamically configured at runtime. |
| 14 | */ |
| 15 | /* |
| 16 | * Copyright (C) 2006-2018, Arm Limited (or its affiliates), All Rights Reserved |
| 17 | * SPDX-License-Identifier: GPL-2.0 |
| 18 | * |
| 19 | * This program is free software; you can redistribute it and/or modify |
| 20 | * it under the terms of the GNU General Public License as published by |
| 21 | * the Free Software Foundation; either version 2 of the License, or |
| 22 | * (at your option) any later version. |
| 23 | * |
| 24 | * This program is distributed in the hope that it will be useful, |
| 25 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 26 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 27 | * GNU General Public License for more details. |
| 28 | * |
| 29 | * You should have received a copy of the GNU General Public License along |
| 30 | * with this program; if not, write to the Free Software Foundation, Inc., |
| 31 | * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. |
| 32 | * |
| 33 | * This file is part of Mbed TLS (https://tls.mbed.org) |
| 34 | */ |
| 35 | #ifndef MBEDTLS_PLATFORM_H |
| 36 | #define MBEDTLS_PLATFORM_H |
| 37 | |
| 38 | #if !defined(MBEDTLS_CONFIG_FILE) |
| 39 | #include "config.h" |
| 40 | #else |
| 41 | #include MBEDTLS_CONFIG_FILE |
| 42 | #endif |
| 43 | |
| 44 | #if defined(MBEDTLS_HAVE_TIME) |
| 45 | #include "platform_time.h" |
| 46 | #endif |
| 47 | |
| 48 | #ifdef __cplusplus |
| 49 | extern "C" { |
| 50 | #endif |
| 51 | |
| 52 | /** |
| 53 | * \name SECTION: Module settings |
| 54 | * |
| 55 | * The configuration options you can set for this module are in this section. |
| 56 | * Either change them in config.h or define them on the compiler command line. |
| 57 | * \{ |
| 58 | */ |
| 59 | |
| 60 | #if !defined(MBEDTLS_PLATFORM_NO_STD_FUNCTIONS) |
| 61 | #include <stdio.h> |
| 62 | #include <stdlib.h> |
| 63 | #include <time.h> |
| 64 | #if !defined(MBEDTLS_PLATFORM_STD_SNPRINTF) |
| 65 | #if defined(_WIN32) |
| 66 | #define MBEDTLS_PLATFORM_STD_SNPRINTF mbedtls_platform_win32_snprintf /**< The default \c snprintf function to use. */ |
| 67 | #else |
| 68 | #define MBEDTLS_PLATFORM_STD_SNPRINTF snprintf /**< The default \c snprintf function to use. */ |
| 69 | #endif |
| 70 | #endif |
| 71 | #if !defined(MBEDTLS_PLATFORM_STD_PRINTF) |
| 72 | #define MBEDTLS_PLATFORM_STD_PRINTF printf /**< The default \c printf function to use. */ |
| 73 | #endif |
| 74 | #if !defined(MBEDTLS_PLATFORM_STD_FPRINTF) |
| 75 | #define MBEDTLS_PLATFORM_STD_FPRINTF fprintf /**< The default \c fprintf function to use. */ |
| 76 | #endif |
| 77 | #if !defined(MBEDTLS_PLATFORM_STD_CALLOC) |
| 78 | #define MBEDTLS_PLATFORM_STD_CALLOC calloc /**< The default \c calloc function to use. */ |
| 79 | #endif |
| 80 | #if !defined(MBEDTLS_PLATFORM_STD_FREE) |
| 81 | #define MBEDTLS_PLATFORM_STD_FREE free /**< The default \c free function to use. */ |
| 82 | #endif |
| 83 | #if !defined(MBEDTLS_PLATFORM_STD_EXIT) |
| 84 | #define MBEDTLS_PLATFORM_STD_EXIT exit /**< The default \c exit function to use. */ |
| 85 | #endif |
| 86 | #if !defined(MBEDTLS_PLATFORM_STD_TIME) |
| 87 | #define MBEDTLS_PLATFORM_STD_TIME time /**< The default \c time function to use. */ |
| 88 | #endif |
| 89 | #if !defined(MBEDTLS_PLATFORM_STD_EXIT_SUCCESS) |
| 90 | #define MBEDTLS_PLATFORM_STD_EXIT_SUCCESS EXIT_SUCCESS /**< The default exit value to use. */ |
| 91 | #endif |
| 92 | #if !defined(MBEDTLS_PLATFORM_STD_EXIT_FAILURE) |
| 93 | #define MBEDTLS_PLATFORM_STD_EXIT_FAILURE EXIT_FAILURE /**< The default exit value to use. */ |
| 94 | #endif |
| 95 | #if defined(MBEDTLS_FS_IO) |
| 96 | #if !defined(MBEDTLS_PLATFORM_STD_NV_SEED_READ) |
| 97 | #define MBEDTLS_PLATFORM_STD_NV_SEED_READ mbedtls_platform_std_nv_seed_read |
| 98 | #endif |
| 99 | #if !defined(MBEDTLS_PLATFORM_STD_NV_SEED_WRITE) |
| 100 | #define MBEDTLS_PLATFORM_STD_NV_SEED_WRITE mbedtls_platform_std_nv_seed_write |
| 101 | #endif |
| 102 | #if !defined(MBEDTLS_PLATFORM_STD_NV_SEED_FILE) |
| 103 | #define MBEDTLS_PLATFORM_STD_NV_SEED_FILE "seedfile" |
| 104 | #endif |
| 105 | #endif /* MBEDTLS_FS_IO */ |
| 106 | #else /* MBEDTLS_PLATFORM_NO_STD_FUNCTIONS */ |
| 107 | #if defined(MBEDTLS_PLATFORM_STD_MEM_HDR) |
| 108 | #include MBEDTLS_PLATFORM_STD_MEM_HDR |
| 109 | #endif |
| 110 | #endif /* MBEDTLS_PLATFORM_NO_STD_FUNCTIONS */ |
| 111 | |
| 112 | |
| 113 | /* \} name SECTION: Module settings */ |
| 114 | |
| 115 | /* |
| 116 | * The function pointers for calloc and free. |
| 117 | */ |
| 118 | #if defined(MBEDTLS_PLATFORM_MEMORY) |
| 119 | #if defined(MBEDTLS_PLATFORM_FREE_MACRO) && \ |
| 120 | defined(MBEDTLS_PLATFORM_CALLOC_MACRO) |
| 121 | #define mbedtls_free MBEDTLS_PLATFORM_FREE_MACRO |
| 122 | #define mbedtls_calloc MBEDTLS_PLATFORM_CALLOC_MACRO |
| 123 | #else |
| 124 | /* For size_t */ |
| 125 | #include <stddef.h> |
| 126 | extern void *mbedtls_calloc( size_t n, size_t size ); |
| 127 | extern void mbedtls_free( void *ptr ); |
| 128 | |
| 129 | /** |
| 130 | * \brief This function dynamically sets the memory-management |
| 131 | * functions used by the library, during runtime. |
| 132 | * |
| 133 | * \param calloc_func The \c calloc function implementation. |
| 134 | * \param free_func The \c free function implementation. |
| 135 | * |
| 136 | * \return \c 0. |
| 137 | */ |
| 138 | int mbedtls_platform_set_calloc_free( void * (*calloc_func)( size_t, size_t ), |
| 139 | void (*free_func)( void * ) ); |
| 140 | #endif /* MBEDTLS_PLATFORM_FREE_MACRO && MBEDTLS_PLATFORM_CALLOC_MACRO */ |
| 141 | #else /* !MBEDTLS_PLATFORM_MEMORY */ |
| 142 | #define mbedtls_free free |
| 143 | #define mbedtls_calloc calloc |
| 144 | #endif /* MBEDTLS_PLATFORM_MEMORY && !MBEDTLS_PLATFORM_{FREE,CALLOC}_MACRO */ |
| 145 | |
| 146 | /* |
| 147 | * The function pointers for fprintf |
| 148 | */ |
| 149 | #if defined(MBEDTLS_PLATFORM_FPRINTF_ALT) |
| 150 | /* We need FILE * */ |
| 151 | #include <stdio.h> |
| 152 | extern int (*mbedtls_fprintf)( FILE *stream, const char *format, ... ); |
| 153 | |
| 154 | /** |
| 155 | * \brief This function dynamically configures the fprintf |
| 156 | * function that is called when the |
| 157 | * mbedtls_fprintf() function is invoked by the library. |
| 158 | * |
| 159 | * \param fprintf_func The \c fprintf function implementation. |
| 160 | * |
| 161 | * \return \c 0. |
| 162 | */ |
| 163 | int mbedtls_platform_set_fprintf( int (*fprintf_func)( FILE *stream, const char *, |
| 164 | ... ) ); |
| 165 | #else |
| 166 | #if defined(MBEDTLS_PLATFORM_FPRINTF_MACRO) |
| 167 | #define mbedtls_fprintf MBEDTLS_PLATFORM_FPRINTF_MACRO |
| 168 | #else |
| 169 | #define mbedtls_fprintf fprintf |
| 170 | #endif /* MBEDTLS_PLATFORM_FPRINTF_MACRO */ |
| 171 | #endif /* MBEDTLS_PLATFORM_FPRINTF_ALT */ |
| 172 | |
| 173 | /* |
| 174 | * The function pointers for printf |
| 175 | */ |
| 176 | #if defined(MBEDTLS_PLATFORM_PRINTF_ALT) |
| 177 | extern int (*mbedtls_printf)( const char *format, ... ); |
| 178 | |
| 179 | /** |
| 180 | * \brief This function dynamically configures the snprintf |
| 181 | * function that is called when the mbedtls_snprintf() |
| 182 | * function is invoked by the library. |
| 183 | * |
| 184 | * \param printf_func The \c printf function implementation. |
| 185 | * |
| 186 | * \return \c 0 on success. |
| 187 | */ |
| 188 | int mbedtls_platform_set_printf( int (*printf_func)( const char *, ... ) ); |
| 189 | #else /* !MBEDTLS_PLATFORM_PRINTF_ALT */ |
| 190 | #if defined(MBEDTLS_PLATFORM_PRINTF_MACRO) |
| 191 | #define mbedtls_printf MBEDTLS_PLATFORM_PRINTF_MACRO |
| 192 | #else |
| 193 | #define mbedtls_printf printf |
| 194 | #endif /* MBEDTLS_PLATFORM_PRINTF_MACRO */ |
| 195 | #endif /* MBEDTLS_PLATFORM_PRINTF_ALT */ |
| 196 | |
| 197 | /* |
| 198 | * The function pointers for snprintf |
| 199 | * |
| 200 | * The snprintf implementation should conform to C99: |
| 201 | * - it *must* always correctly zero-terminate the buffer |
| 202 | * (except when n == 0, then it must leave the buffer untouched) |
| 203 | * - however it is acceptable to return -1 instead of the required length when |
| 204 | * the destination buffer is too short. |
| 205 | */ |
| 206 | #if defined(_WIN32) |
| 207 | /* For Windows (inc. MSYS2), we provide our own fixed implementation */ |
| 208 | int mbedtls_platform_win32_snprintf( char *s, size_t n, const char *fmt, ... ); |
| 209 | #endif |
| 210 | |
| 211 | #if defined(MBEDTLS_PLATFORM_SNPRINTF_ALT) |
| 212 | extern int (*mbedtls_snprintf)( char * s, size_t n, const char * format, ... ); |
| 213 | |
| 214 | /** |
| 215 | * \brief This function allows configuring a custom |
| 216 | * \c snprintf function pointer. |
| 217 | * |
| 218 | * \param snprintf_func The \c snprintf function implementation. |
| 219 | * |
| 220 | * \return \c 0 on success. |
| 221 | */ |
| 222 | int mbedtls_platform_set_snprintf( int (*snprintf_func)( char * s, size_t n, |
| 223 | const char * format, ... ) ); |
| 224 | #else /* MBEDTLS_PLATFORM_SNPRINTF_ALT */ |
| 225 | #if defined(MBEDTLS_PLATFORM_SNPRINTF_MACRO) |
| 226 | #define mbedtls_snprintf MBEDTLS_PLATFORM_SNPRINTF_MACRO |
| 227 | #else |
| 228 | #define mbedtls_snprintf MBEDTLS_PLATFORM_STD_SNPRINTF |
| 229 | #endif /* MBEDTLS_PLATFORM_SNPRINTF_MACRO */ |
| 230 | #endif /* MBEDTLS_PLATFORM_SNPRINTF_ALT */ |
| 231 | |
| 232 | /* |
| 233 | * The function pointers for exit |
| 234 | */ |
| 235 | #if defined(MBEDTLS_PLATFORM_EXIT_ALT) |
| 236 | extern void (*mbedtls_exit)( int status ); |
| 237 | |
| 238 | /** |
| 239 | * \brief This function dynamically configures the exit |
| 240 | * function that is called when the mbedtls_exit() |
| 241 | * function is invoked by the library. |
| 242 | * |
| 243 | * \param exit_func The \c exit function implementation. |
| 244 | * |
| 245 | * \return \c 0 on success. |
| 246 | */ |
| 247 | int mbedtls_platform_set_exit( void (*exit_func)( int status ) ); |
| 248 | #else |
| 249 | #if defined(MBEDTLS_PLATFORM_EXIT_MACRO) |
| 250 | #define mbedtls_exit MBEDTLS_PLATFORM_EXIT_MACRO |
| 251 | #else |
| 252 | #define mbedtls_exit exit |
| 253 | #endif /* MBEDTLS_PLATFORM_EXIT_MACRO */ |
| 254 | #endif /* MBEDTLS_PLATFORM_EXIT_ALT */ |
| 255 | |
| 256 | /* |
| 257 | * The default exit values |
| 258 | */ |
| 259 | #if defined(MBEDTLS_PLATFORM_STD_EXIT_SUCCESS) |
| 260 | #define MBEDTLS_EXIT_SUCCESS MBEDTLS_PLATFORM_STD_EXIT_SUCCESS |
| 261 | #else |
| 262 | #define MBEDTLS_EXIT_SUCCESS 0 |
| 263 | #endif |
| 264 | #if defined(MBEDTLS_PLATFORM_STD_EXIT_FAILURE) |
| 265 | #define MBEDTLS_EXIT_FAILURE MBEDTLS_PLATFORM_STD_EXIT_FAILURE |
| 266 | #else |
| 267 | #define MBEDTLS_EXIT_FAILURE 1 |
| 268 | #endif |
| 269 | |
| 270 | /* |
| 271 | * The function pointers for reading from and writing a seed file to |
| 272 | * Non-Volatile storage (NV) in a platform-independent way |
| 273 | * |
| 274 | * Only enabled when the NV seed entropy source is enabled |
| 275 | */ |
| 276 | #if defined(MBEDTLS_ENTROPY_NV_SEED) |
| 277 | #if !defined(MBEDTLS_PLATFORM_NO_STD_FUNCTIONS) && defined(MBEDTLS_FS_IO) |
| 278 | /* Internal standard platform definitions */ |
| 279 | int mbedtls_platform_std_nv_seed_read( unsigned char *buf, size_t buf_len ); |
| 280 | int mbedtls_platform_std_nv_seed_write( unsigned char *buf, size_t buf_len ); |
| 281 | #endif |
| 282 | |
| 283 | #if defined(MBEDTLS_PLATFORM_NV_SEED_ALT) |
| 284 | extern int (*mbedtls_nv_seed_read)( unsigned char *buf, size_t buf_len ); |
| 285 | extern int (*mbedtls_nv_seed_write)( unsigned char *buf, size_t buf_len ); |
| 286 | |
| 287 | /** |
| 288 | * \brief This function allows configuring custom seed file writing and |
| 289 | * reading functions. |
| 290 | * |
| 291 | * \param nv_seed_read_func The seed reading function implementation. |
| 292 | * \param nv_seed_write_func The seed writing function implementation. |
| 293 | * |
| 294 | * \return \c 0 on success. |
| 295 | */ |
| 296 | int mbedtls_platform_set_nv_seed( |
| 297 | int (*nv_seed_read_func)( unsigned char *buf, size_t buf_len ), |
| 298 | int (*nv_seed_write_func)( unsigned char *buf, size_t buf_len ) |
| 299 | ); |
| 300 | #else |
| 301 | #if defined(MBEDTLS_PLATFORM_NV_SEED_READ_MACRO) && \ |
| 302 | defined(MBEDTLS_PLATFORM_NV_SEED_WRITE_MACRO) |
| 303 | #define mbedtls_nv_seed_read MBEDTLS_PLATFORM_NV_SEED_READ_MACRO |
| 304 | #define mbedtls_nv_seed_write MBEDTLS_PLATFORM_NV_SEED_WRITE_MACRO |
| 305 | #else |
| 306 | #define mbedtls_nv_seed_read mbedtls_platform_std_nv_seed_read |
| 307 | #define mbedtls_nv_seed_write mbedtls_platform_std_nv_seed_write |
| 308 | #endif |
| 309 | #endif /* MBEDTLS_PLATFORM_NV_SEED_ALT */ |
| 310 | #endif /* MBEDTLS_ENTROPY_NV_SEED */ |
| 311 | |
| 312 | #if !defined(MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT) |
| 313 | |
| 314 | /** |
| 315 | * \brief The platform context structure. |
| 316 | * |
| 317 | * \note This structure may be used to assist platform-specific |
| 318 | * setup or teardown operations. |
| 319 | */ |
| 320 | typedef struct mbedtls_platform_context |
| 321 | { |
| 322 | char dummy; /**< A placeholder member, as empty structs are not portable. */ |
| 323 | } |
| 324 | mbedtls_platform_context; |
| 325 | |
| 326 | #else |
| 327 | #include "platform_alt.h" |
| 328 | #endif /* !MBEDTLS_PLATFORM_SETUP_TEARDOWN_ALT */ |
| 329 | |
| 330 | /** |
| 331 | * \brief This function performs any platform-specific initialization |
| 332 | * operations. |
| 333 | * |
| 334 | * \note This function should be called before any other library functions. |
| 335 | * |
| 336 | * Its implementation is platform-specific, and unless |
| 337 | * platform-specific code is provided, it does nothing. |
| 338 | * |
| 339 | * \note The usage and necessity of this function is dependent on the platform. |
| 340 | * |
| 341 | * \param ctx The platform context. |
| 342 | * |
| 343 | * \return \c 0 on success. |
| 344 | */ |
| 345 | int mbedtls_platform_setup( mbedtls_platform_context *ctx ); |
| 346 | /** |
| 347 | * \brief This function performs any platform teardown operations. |
| 348 | * |
| 349 | * \note This function should be called after every other Mbed TLS module |
| 350 | * has been correctly freed using the appropriate free function. |
| 351 | * |
| 352 | * Its implementation is platform-specific, and unless |
| 353 | * platform-specific code is provided, it does nothing. |
| 354 | * |
| 355 | * \note The usage and necessity of this function is dependent on the platform. |
| 356 | * |
| 357 | * \param ctx The platform context. |
| 358 | * |
| 359 | */ |
| 360 | void mbedtls_platform_teardown( mbedtls_platform_context *ctx ); |
| 361 | |
| 362 | #ifdef __cplusplus |
| 363 | } |
| 364 | #endif |
| 365 | |
| 366 | #endif /* platform.h */ |