errno_t __cdecl rand_s
(
unsigned int* _RandomValue
) {
PGENRANDOM pfnRtlGenRandom = _decode_pointer(g_pfnRtlGenRandom);
_VALIDATE_RETURN_ERRCODE(_RandomValue != NULL, EINVAL);
*_RandomValue = 0; // Review : better value to initialize it to?
if (pfnRtlGenRandom == NULL) {
PGENRANDOM encoded;
void* enull;
// Advapi32.dll is unloaded when the App exits.
HMODULE hAdvApi32 = LoadLibrary("ADVAPI32.DLL");
if (!hAdvApi32) {
_VALIDATE_RETURN_ERRCODE(("rand_s is not available on this platform", 0), EINVAL);
}
pfnRtlGenRandom = (PGENRANDOM) GetProcAddress(hAdvApi32, _TO_STR(RtlGenRandom));
if (pfnRtlGenRandom == NULL) {
_VALIDATE_RETURN_ERRCODE(("rand_s is not available on this platform", 0), _get_errno_from_oserr(GetLastError()));
}
encoded = (PGENRANDOM) _encode_pointer(pfnRtlGenRandom);
enull = _encoded_null();
#ifdef _M_IX86
if ((void*)(LONG_PTR)InterlockedExchange(
(LONG*)&g_pfnRtlGenRandom,
(LONG)(LONG_PTR)encoded)
!= enull)
#else /* _M_IX86 */
if (InterlockedExchangePointer(
(void**)&g_pfnRtlGenRandom,
(void*)encoded)
!= enull)
#endif /* _M_IX86 */
{
/* A different thread has already loaded advapi32.dll. */
FreeLibrary(hAdvApi32);
}
}
if (!(*pfnRtlGenRandom)(_RandomValue, (ULONG)sizeof(unsigned int))) {
errno = ENOMEM;
return errno;
}
return 0;
}
errno_t __cdecl rand_s
(
unsigned int *_RandomValue
)
{
PGENRANDOM pfnRtlGenRandom = (PGENRANDOM) DecodePointer(g_pfnRtlGenRandom);
_VALIDATE_RETURN_ERRCODE( _RandomValue != NULL, EINVAL );
*_RandomValue = 0; // Review : better value to initialize it to?
if ( pfnRtlGenRandom == NULL )
{
PGENRANDOM encoded;
void* enull;
#ifdef _CORESYS
#define RAND_DLL L"cryptbase.dll"
#else /* _CORESYS */
#define RAND_DLL L"ADVAPI32.DLL"
#endif /* _CORESYS */
// advapi32.dll/cryptbase.dll is unloaded when the App exits.
HMODULE hRandDll = LoadLibraryExW(RAND_DLL, NULL, LOAD_LIBRARY_SEARCH_SYSTEM32);
#ifndef _CORESYS
if (!hRandDll && GetLastError() == ERROR_INVALID_PARAMETER)
{
// LOAD_LIBRARY_SEARCH_SYSTEM32 is not supported on this platfrom,
// try one more time using default options
hRandDll = LoadLibraryExW(RAND_DLL, NULL, 0);
}
#endif /* _CORESYS */
if (!hRandDll)
{
_VALIDATE_RETURN_ERRCODE(("rand_s is not available on this platform", 0), EINVAL);
}
pfnRtlGenRandom = ( PGENRANDOM ) GetProcAddress( hRandDll, _TO_STR( RtlGenRandom ) );
if ( pfnRtlGenRandom == NULL )
{
_VALIDATE_RETURN_ERRCODE(("rand_s is not available on this platform", 0), _get_errno_from_oserr(GetLastError()));
}
encoded = (PGENRANDOM) EncodePointer(pfnRtlGenRandom);
enull = EncodePointer(NULL);
#ifdef _M_IX86
if ( (void*)(LONG_PTR)InterlockedExchange(
( LONG* )&g_pfnRtlGenRandom,
( LONG )( LONG_PTR )encoded)
!= enull )
#else /* _M_IX86 */
if ( InterlockedExchangePointer(
( void** )&g_pfnRtlGenRandom,
( void* )encoded)
!= enull )
#endif /* _M_IX86 */
{
/* A different thread has already loaded advapi32.dll/cryptbase.dll. */
FreeLibrary( hRandDll );
}
}
if ( !(*pfnRtlGenRandom)( _RandomValue, ( ULONG )sizeof( unsigned int ) ) )
{
errno = ENOMEM;
return errno;
}
return 0;
}
