NTSTATUS WINAPI RegisterProvider(BOOLEAN KernelMode)
{
NTSTATUS status;
UNREFERENCED_PARAMETER(KernelMode);
status = BCryptRegisterProvider(VIRTRNG_PROVIDER_NAME, CRYPT_OVERWRITE,
&VirtRngProvider);
if (!NT_SUCCESS(status))
{
SetupWriteTextLogError(SetupGetThreadLogToken(),
TXTLOG_INSTALLER,
TXTLOG_ERROR,
ToDosError(status),
"Failed to register as a CNG provider.");
return status;
}
status = BCryptAddContextFunctionProvider(CRYPT_LOCAL, NULL,
BCRYPT_RNG_INTERFACE, BCRYPT_RNG_ALGORITHM, VIRTRNG_PROVIDER_NAME,
CRYPT_PRIORITY_BOTTOM);
if (!NT_SUCCESS(status))
{
SetupWriteTextLogError(SetupGetThreadLogToken(),
TXTLOG_INSTALLER,
TXTLOG_ERROR,
ToDosError(status),
"Failed to add cryptographic function.");
}
return status;
}
NTSTATUS WINAPI UnregisterProvider()
{
NTSTATUS status;
status = BCryptRemoveContextFunctionProvider(CRYPT_LOCAL, NULL,
BCRYPT_RNG_INTERFACE, BCRYPT_RNG_ALGORITHM, VIRTRNG_PROVIDER_NAME);
if (!NT_SUCCESS(status))
{
SetupWriteTextLogError(SetupGetThreadLogToken(),
TXTLOG_INSTALLER,
TXTLOG_WARNING,
ToDosError(status),
"Failed to remove cryptographic function.");
}
status = BCryptUnregisterProvider(VIRTRNG_PROVIDER_NAME);
if (!NT_SUCCESS(status))
{
SetupWriteTextLogError(SetupGetThreadLogToken(),
TXTLOG_INSTALLER,
TXTLOG_WARNING,
ToDosError(status),
"Failed to unregister as a CNG provider.");
}
return STATUS_SUCCESS;
}
static DWORD ToDosError(NTSTATUS status)
{
DWORD error = NO_ERROR;
HMODULE ntdll;
RtlNtStatusToDosErrorFunc RtlNtStatusToDosError;
ntdll = LoadLibrary(L"Ntdll.dll");
if (ntdll != NULL)
{
RtlNtStatusToDosError = (RtlNtStatusToDosErrorFunc)
GetProcAddress(ntdll, "RtlNtStatusToDosError");
if (RtlNtStatusToDosError != NULL)
{
error = RtlNtStatusToDosError(status);
}
else
{
error = GetLastError();
SetupWriteTextLogError(SetupGetThreadLogToken(),
TXTLOG_INSTALLER,
TXTLOG_ERROR,
error,
"RtlNtStatusToDosError function not found.");
}
}
else
{
error = GetLastError();
SetupWriteTextLogError(SetupGetThreadLogToken(),
TXTLOG_INSTALLER,
TXTLOG_ERROR,
error,
"Failed to load ntdll.dll.");
}
return error;
}
static VOID
#pragma prefast(suppress:6262) // Function uses '1036' bytes of stack: exceeds /analyze:stacksize'1024'
__Log(
IN const CHAR *Format,
IN ...
)
{
TCHAR Buffer[MAXIMUM_BUFFER_SIZE];
va_list Arguments;
size_t Length;
SP_LOG_TOKEN LogToken;
DWORD Category;
DWORD Flags;
HRESULT Result;
va_start(Arguments, Format);
Result = StringCchVPrintf(Buffer, MAXIMUM_BUFFER_SIZE, Format, Arguments);
va_end(Arguments);
if (Result != S_OK && Result != STRSAFE_E_INSUFFICIENT_BUFFER)
return;
Result = StringCchLength(Buffer, MAXIMUM_BUFFER_SIZE, &Length);
if (Result != S_OK)
return;
LogToken = SetupGetThreadLogToken();
Category = TXTLOG_VENDOR;
Flags = TXTLOG_WARNING;
SetupWriteTextLog(LogToken, Category, Flags, Buffer);
Length = __min(MAXIMUM_BUFFER_SIZE - 1, Length + 2);
__analysis_assume(Length < MAXIMUM_BUFFER_SIZE);
__analysis_assume(Length >= 2);
Buffer[Length] = '\0';
Buffer[Length - 1] = '\n';
Buffer[Length - 2] = '\r';
OutputDebugString(Buffer);
}
