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PODeny USB arrival
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copied!<p>I am working on USB Monitor in C# and I wanted to be able to react after the system driver processed arrival and enabled the arriving device, but faster than application level processes (Explorer). I wanted to examine device for autorun.inf and if found to DENY the arrival. I used BROADCAST_QUERY_DENY as described on MSDN but no success. Here is the code (assuming USB arrives as 'I' drive):</p> <pre><code> switch (msg.Msg) { case Win32CODES.WM_DEVICECHANGE: { if (msg.LParam != IntPtr.Zero) { DEV_BROADCAST_HDR pHdr = (DEV_BROADCAST_HDR)Marshal.PtrToStructure(msg.LParam, typeof(DEV_BROADCAST_HDR)); switch ((int)msg.WParam) { case Win32CODES.DBT_DEVICEARRIVAL: { if (pHdr.dbch_devicetype == Win32CODES.DBT_DEVTYP_VOLUME) { DEV_BROADCAST_VOLUME pVol = (DEV_BROADCAST_VOLUME)Marshal.PtrToStructure(msg.LParam, typeof(DEV_BROADCAST_VOLUME)); Char c = GetDriveLetter(pVol.dbcv_unitmask); if (c == 'I') { msg.Result = new IntPtr(Win32CODES.BROADCAST_QUERY_DENY ); base.WndProc(ref msg); return; } } break; } } } break; } } base.WndProc(ref msg); } </code></pre> <p>Then I tried another way but again no success.</p> <pre><code> switch (msg.Msg) { case Win32CODES.WM_DEVICECHANGE: { if (msg.LParam != IntPtr.Zero) { DEV_BROADCAST_HDR pHdr = (DEV_BROADCAST_HDR)Marshal.PtrToStructure(msg.LParam, typeof(DEV_BROADCAST_HDR)); switch ((int)msg.WParam) { case Win32CODES.DBT_DEVICEARRIVAL: { if (pHdr.dbch_devicetype == Win32CODES.DBT_DEVTYP_VOLUME) { DEV_BROADCAST_VOLUME pVol = (DEV_BROADCAST_VOLUME)Marshal.PtrToStructure(msg.LParam, typeof(DEV_BROADCAST_VOLUME)); Char c = GetDriveLetter(pVol.dbcv_unitmask); if (c == 'I') { int bytesReturned = 0; IntPtr buffer = Marshal.AllocHGlobal(sizeof(int)); SafeFileHandle _hdev = CreateFileR(c.ToString()); bool result = DeviceIoControl(_hdev, CTL_CODE(0x00000033, 0x0400, 0, 1), IntPtr.Zero, 0, buffer, sizeof(int), out bytesReturned, IntPtr.Zero); int sessionId = Marshal.ReadInt32(buffer); Marshal.FreeHGlobal(buffer); } } break; } } } break; } } base.WndProc(ref msg); </code></pre> <p>Is there a way to accomplish this? Thanks..</p>

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