/*

 *  Threading abstraction layer

 *

 *  Copyright The Mbed TLS Contributors

 *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later

 */

/*

 * Ensure gmtime_r is available even with -std=c99; must be defined before

 * mbedtls_config.h, which pulls in glibc's features.h. Harmless on other platforms.

 */

#if !defined(_POSIX_C_SOURCE)

#define _POSIX_C_SOURCE 200112L

#endif

#include "common.h"

#if defined(MBEDTLS_THREADING_C)

#include "mbedtls/threading.h"

#if defined(MBEDTLS_HAVE_TIME_DATE) && !defined(MBEDTLS_PLATFORM_GMTIME_R_ALT)

#if !defined(_WIN32) && (defined(unix) || \

    defined(__unix) || defined(__unix__) || (defined(__APPLE__) && \

    defined(__MACH__)))

#include <unistd.h>

#endif /* !_WIN32 && (unix || __unix || __unix__ ||

        * (__APPLE__ && __MACH__)) */

#if !((defined(_POSIX_VERSION) && _POSIX_VERSION >= 200809L) ||     \

    (defined(_POSIX_THREAD_SAFE_FUNCTIONS) &&                     \

    _POSIX_THREAD_SAFE_FUNCTIONS >= 200112L))

/*

 * This is a convenience shorthand macro to avoid checking the long

 * preprocessor conditions above. Ideally, we could expose this macro in

 * platform_util.h and simply use it in platform_util.c, threading.c and

 * threading.h. However, this macro is not part of the Mbed TLS public API, so

 * we keep it private by only defining it in this file

 */

#if !(defined(_WIN32) && !defined(EFIX64) && !defined(EFI32))

#define THREADING_USE_GMTIME

#endif /* ! ( defined(_WIN32) && !defined(EFIX64) && !defined(EFI32) ) */

#endif /* !( ( defined(_POSIX_VERSION) && _POSIX_VERSION >= 200809L ) || \

             ( defined(_POSIX_THREAD_SAFE_FUNCTIONS ) && \

                _POSIX_THREAD_SAFE_FUNCTIONS >= 200112L ) ) */

#endif /* MBEDTLS_HAVE_TIME_DATE && !MBEDTLS_PLATFORM_GMTIME_R_ALT */

#if defined(MBEDTLS_THREADING_PTHREAD)

static void threading_mutex_init_pthread(mbedtls_threading_mutex_t *mutex)

{

    if (mutex == NULL) {

        return;

    }

    /* One problem here is that calling lock on a pthread mutex without first

     * having initialised it is undefined behaviour. Obviously we cannot check

     * this here in a thread safe manner without a significant performance

     * hit, so state transitions are checked in tests only via the state

     * variable. Please make sure any new mutex that gets added is exercised in

     * tests; see framework/tests/src/threading_helpers.c for more details. */

    (void) pthread_mutex_init(&mutex->mutex, NULL);

}

static void threading_mutex_free_pthread(mbedtls_threading_mutex_t *mutex)

{

    if (mutex == NULL) {

        return;

    }

    (void) pthread_mutex_destroy(&mutex->mutex);

}

static int threading_mutex_lock_pthread(mbedtls_threading_mutex_t *mutex)

{

    if (mutex == NULL) {

        return MBEDTLS_ERR_THREADING_BAD_INPUT_DATA;

    }

    if (pthread_mutex_lock(&mutex->mutex) != 0) {

        return MBEDTLS_ERR_THREADING_MUTEX_ERROR;

    }

    return 0;

}

static int threading_mutex_unlock_pthread(mbedtls_threading_mutex_t *mutex)

{

    if (mutex == NULL) {

        return MBEDTLS_ERR_THREADING_BAD_INPUT_DATA;

    }

    if (pthread_mutex_unlock(&mutex->mutex) != 0) {

        return MBEDTLS_ERR_THREADING_MUTEX_ERROR;

    }

    return 0;

}

void (*mbedtls_mutex_init)(mbedtls_threading_mutex_t *) = threading_mutex_init_pthread;

void (*mbedtls_mutex_free)(mbedtls_threading_mutex_t *) = threading_mutex_free_pthread;

int (*mbedtls_mutex_lock)(mbedtls_threading_mutex_t *) = threading_mutex_lock_pthread;

int (*mbedtls_mutex_unlock)(mbedtls_threading_mutex_t *) = threading_mutex_unlock_pthread;

/*

 * With pthreads we can statically initialize mutexes

 */

#define MUTEX_INIT  = { PTHREAD_MUTEX_INITIALIZER, 1 }

#endif /* MBEDTLS_THREADING_PTHREAD */

#if defined(MBEDTLS_THREADING_ALT)

static int threading_mutex_fail(mbedtls_threading_mutex_t *mutex)

{

    ((void) mutex);

    return MBEDTLS_ERR_THREADING_BAD_INPUT_DATA;

}

static void threading_mutex_dummy(mbedtls_threading_mutex_t *mutex)

{

    ((void) mutex);

    return;

}

void (*mbedtls_mutex_init)(mbedtls_threading_mutex_t *) = threading_mutex_dummy;

void (*mbedtls_mutex_free)(mbedtls_threading_mutex_t *) = threading_mutex_dummy;

int (*mbedtls_mutex_lock)(mbedtls_threading_mutex_t *) = threading_mutex_fail;

int (*mbedtls_mutex_unlock)(mbedtls_threading_mutex_t *) = threading_mutex_fail;

/*

 * Set functions pointers and initialize global mutexes

 */

void mbedtls_threading_set_alt(void (*mutex_init)(mbedtls_threading_mutex_t *),

                               void (*mutex_free)(mbedtls_threading_mutex_t *),

                               int (*mutex_lock)(mbedtls_threading_mutex_t *),

                               int (*mutex_unlock)(mbedtls_threading_mutex_t *))

{

    mbedtls_mutex_init = mutex_init;

    mbedtls_mutex_free = mutex_free;

    mbedtls_mutex_lock = mutex_lock;

    mbedtls_mutex_unlock = mutex_unlock;

#if defined(MBEDTLS_FS_IO)

    mbedtls_mutex_init(&mbedtls_threading_readdir_mutex);

#endif

#if defined(THREADING_USE_GMTIME)

    mbedtls_mutex_init(&mbedtls_threading_gmtime_mutex);

#endif

#if defined(MBEDTLS_PSA_CRYPTO_C)

    mbedtls_mutex_init(&mbedtls_threading_key_slot_mutex);

    mbedtls_mutex_init(&mbedtls_threading_psa_globaldata_mutex);

    mbedtls_mutex_init(&mbedtls_threading_psa_rngdata_mutex);

#endif

}

/*

 * Free global mutexes

 */

void mbedtls_threading_free_alt(void)

{

#if defined(MBEDTLS_FS_IO)

    mbedtls_mutex_free(&mbedtls_threading_readdir_mutex);

#endif

#if defined(THREADING_USE_GMTIME)

    mbedtls_mutex_free(&mbedtls_threading_gmtime_mutex);

#endif

#if defined(MBEDTLS_PSA_CRYPTO_C)

    mbedtls_mutex_free(&mbedtls_threading_key_slot_mutex);

    mbedtls_mutex_free(&mbedtls_threading_psa_globaldata_mutex);

    mbedtls_mutex_free(&mbedtls_threading_psa_rngdata_mutex);

#endif

}

#endif /* MBEDTLS_THREADING_ALT */

/*

 * Define global mutexes

 */

#ifndef MUTEX_INIT

#define MUTEX_INIT

#endif

#if defined(MBEDTLS_FS_IO)

mbedtls_threading_mutex_t mbedtls_threading_readdir_mutex MUTEX_INIT;

#endif

#if defined(THREADING_USE_GMTIME)

mbedtls_threading_mutex_t mbedtls_threading_gmtime_mutex MUTEX_INIT;

#endif

#if defined(MBEDTLS_PSA_CRYPTO_C)

mbedtls_threading_mutex_t mbedtls_threading_key_slot_mutex MUTEX_INIT;

mbedtls_threading_mutex_t mbedtls_threading_psa_globaldata_mutex MUTEX_INIT;

mbedtls_threading_mutex_t mbedtls_threading_psa_rngdata_mutex MUTEX_INIT;

#endif

#endif /* MBEDTLS_THREADING_C */