/*
 * Common and shared functions used by multiple modules in the Mbed TLS
 * library.
 *
 *  Copyright The Mbed TLS Contributors
 *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
 */

#if !defined(_POSIX_C_SOURCE) && !defined(__OpenBSD__)
#define _POSIX_C_SOURCE 200112L
#endif

#if !defined(_GNU_SOURCE)

#define _GNU_SOURCE
#endif

#include "common.h"

#include "mbedtls/platform_util.h"
#include "mbedtls/platform.h"
#include "mbedtls/threading.h"

#include <stddef.h>

#ifndef __STDC_WANT_LIB_EXT1__
#define __STDC_WANT_LIB_EXT1__ 1
#endif
#include <string.h>

#if defined(_WIN32)
#include <windows.h>
#endif

#if defined(__GLIBC__) && (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 25)
#define MBEDTLS_PLATFORM_HAS_EXPLICIT_BZERO 1
#elif (defined(__FreeBSD__) && (__FreeBSD_version >= 1100037)) || defined(__OpenBSD__)
#define MBEDTLS_PLATFORM_HAS_EXPLICIT_BZERO 1
#endif

#if !defined(MBEDTLS_PLATFORM_ZEROIZE_ALT)

#undef HAVE_MEMORY_SANITIZER
#if defined(__has_feature)
#if __has_feature(memory_sanitizer)
#include <sanitizer/msan_interface.h>
#define HAVE_MEMORY_SANITIZER
#endif
#endif

#if !defined(MBEDTLS_PLATFORM_HAS_EXPLICIT_BZERO) && !(defined(__STDC_LIB_EXT1__) && \
    !defined(__IAR_SYSTEMS_ICC__)) \
    && !defined(_WIN32)
static void *(*const volatile memset_func)(void *, int, size_t) = memset;
#endif

void mbedtls_platform_zeroize(void *buf, size_t len)
{
    if (len > 0) {
#if defined(MBEDTLS_PLATFORM_HAS_EXPLICIT_BZERO)
        explicit_bzero(buf, len);
#if defined(HAVE_MEMORY_SANITIZER)

        __msan_unpoison(buf, len);
#endif
#elif defined(__STDC_LIB_EXT1__) && !defined(__IAR_SYSTEMS_ICC__)
        memset_s(buf, len, 0, len);
#elif defined(_WIN32)
        SecureZeroMemory(buf, len);
#else
        memset_func(buf, 0, len);
#endif

#if defined(__GNUC__)

#if defined(__clang__) || (__GNUC__ >= 10)
        asm volatile ("" : : "m" (*(char (*)[len]) buf) :);
#endif
#endif
    }
}
#endif

void mbedtls_zeroize_and_free(void *buf, size_t len)
{
    if (buf != NULL) {
        mbedtls_platform_zeroize(buf, len);
    }

    mbedtls_free(buf);
}

#if defined(MBEDTLS_HAVE_TIME_DATE) && !defined(MBEDTLS_PLATFORM_GMTIME_R_ALT)
#include <time.h>
#if !defined(_WIN32) && (defined(unix) || \
    defined(__unix) || defined(__unix__) || (defined(__APPLE__) && \
    defined(__MACH__)) || defined(__midipix__))
#include <unistd.h>
#endif

#if !((defined(_POSIX_VERSION) && _POSIX_VERSION >= 200809L) ||     \
    (defined(_POSIX_THREAD_SAFE_FUNCTIONS) &&                     \
    _POSIX_THREAD_SAFE_FUNCTIONS >= 200112L))

#if !(defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)) || \
    (defined(__MINGW32__) && !defined(__MINGW64_VERSION_MAJOR))
#define PLATFORM_UTIL_USE_GMTIME
#endif

#endif

struct tm *mbedtls_platform_gmtime_r(const mbedtls_time_t *tt,
                                     struct tm *tm_buf)
{
#if defined(_WIN32) && !defined(PLATFORM_UTIL_USE_GMTIME)
#if defined(__STDC_LIB_EXT1__)
    return (gmtime_s(tt, tm_buf) == 0) ? NULL : tm_buf;
#else

    return (gmtime_s(tm_buf, tt) == 0) ? tm_buf : NULL;
#endif
#elif !defined(PLATFORM_UTIL_USE_GMTIME)
    return gmtime_r(tt, tm_buf);
#else
    struct tm *lt;

#if defined(MBEDTLS_THREADING_C)
    if (mbedtls_mutex_lock(&mbedtls_threading_gmtime_mutex) != 0) {
        return NULL;
    }
#endif

    lt = gmtime(tt);

    if (lt != NULL) {
        memcpy(tm_buf, lt, sizeof(struct tm));
    }

#if defined(MBEDTLS_THREADING_C)
    if (mbedtls_mutex_unlock(&mbedtls_threading_gmtime_mutex) != 0) {
        return NULL;
    }
#endif

    return (lt == NULL) ? NULL : tm_buf;
#endif
}
#endif

#if defined(MBEDTLS_TEST_HOOKS)
void (*mbedtls_test_hook_test_fail)(const char *, int, const char *);
#endif

#if defined(MBEDTLS_HAVE_TIME) && !defined(MBEDTLS_PLATFORM_MS_TIME_ALT)

#include <time.h>
#if !defined(_WIN32) && \
    (defined(unix) || defined(__unix) || defined(__unix__) || \
    (defined(__APPLE__) && defined(__MACH__)) || defined(__HAIKU__) || defined(__midipix__))
#include <unistd.h>
#endif \

#if (defined(_POSIX_VERSION) && _POSIX_VERSION >= 199309L) || defined(__HAIKU__)
mbedtls_ms_time_t mbedtls_ms_time(void)
{
    int ret;
    struct timespec tv;
    mbedtls_ms_time_t current_ms;

#if defined(__linux__) && defined(CLOCK_BOOTTIME) || defined(__midipix__)
    ret = clock_gettime(CLOCK_BOOTTIME, &tv);
#else
    ret = clock_gettime(CLOCK_MONOTONIC, &tv);
#endif
    if (ret) {
        return time(NULL) * 1000;
    }

    current_ms = tv.tv_sec;

    return current_ms*1000 + tv.tv_nsec / 1000000;
}
#elif defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || \
    defined(__MINGW32__) || defined(_WIN64)
#include <windows.h>
mbedtls_ms_time_t mbedtls_ms_time(void)
{
    FILETIME ct;
    mbedtls_ms_time_t current_ms;

    GetSystemTimeAsFileTime(&ct);
    current_ms = ((mbedtls_ms_time_t) ct.dwLowDateTime +
                  ((mbedtls_ms_time_t) (ct.dwHighDateTime) << 32LL))/10000;
    return current_ms;
}
#else
#error "No mbedtls_ms_time available"
#endif
#endif
