Вот полезный метод, который делает это:
var signed = IsSigned(@"c:\windows\explorer.exe");
...
public static bool IsSigned(string filePath)
{
if (filePath == null)
throw new ArgumentNullException(nameof(filePath));
var file = new WINTRUST_FILE_INFO();
file.cbStruct = Marshal.SizeOf(typeof(WINTRUST_FILE_INFO));
file.pcwszFilePath = filePath;
var data = new WINTRUST_DATA();
data.cbStruct = Marshal.SizeOf(typeof(WINTRUST_DATA));
data.dwUIChoice = WTD_UI_NONE;
data.dwUnionChoice = WTD_CHOICE_FILE;
data.fdwRevocationChecks = WTD_REVOKE_NONE;
data.pFile = Marshal.AllocHGlobal(file.cbStruct);
Marshal.StructureToPtr(file, data.pFile, false);
int hr;
try
{
hr = WinVerifyTrust(INVALID_HANDLE_VALUE, WINTRUST_ACTION_GENERIC_VERIFY_V2, ref data);
}
finally
{
Marshal.FreeHGlobal(data.pFile);
}
return hr == 0;
}
[StructLayoutAttribute(LayoutKind.Sequential, CharSet = CharSet.Unicode)]
private struct WINTRUST_FILE_INFO
{
public int cbStruct;
public string pcwszFilePath;
public IntPtr hFile;
public IntPtr pgKnownSubject;
}
[StructLayoutAttribute(LayoutKind.Sequential)]
private struct WINTRUST_DATA
{
public int cbStruct;
public IntPtr pPolicyCallbackData;
public IntPtr pSIPClientData;
public int dwUIChoice;
public int fdwRevocationChecks;
public int dwUnionChoice;
public IntPtr pFile;
public int dwStateAction;
public IntPtr hWVTStateData;
public IntPtr pwszURLReference;
public int dwProvFlags;
public int dwUIContext;
public IntPtr pSignatureSettings;
}
private const int WTD_UI_NONE = 2;
private const int WTD_REVOKE_NONE = 0;
private const int WTD_CHOICE_FILE = 1;
private static readonly IntPtr INVALID_HANDLE_VALUE = new IntPtr(-1);
private static readonly Guid WINTRUST_ACTION_GENERIC_VERIFY_V2 = new Guid("{00AAC56B-CD44-11d0-8CC2-00C04FC295EE}");
[DllImport("wintrust.dll")]
private static extern int WinVerifyTrust(IntPtr hwnd, [MarshalAs(UnmanagedType.LPStruct)] Guid pgActionID, ref WINTRUST_DATA pWVTData);