Problem in USB read-Only mini filter.

NTFSD
1

Hello All,

I had to implement a mini filler to turn removable disks into Read-only or completely block all access.

the following threads were of great help (https://www.osronline.com/showthread.cfm?link=267440,
https://www.osronline.com/showthread.cfm?link=161769) as I decided to block on a user basis as suggested.
Also, the mini filter model appears to be good for this since I have the flexibility to define access policies to the removable disks.
I was able to turn all removable disks into read-only using a mini filler model but then comes my problem.
When I connect a phone: apple or android, I expect the filter to block all access or to turn the internal storage into a read-only one but it’s not.
I don’t get any notifications from the instanceSetUp callback so I am wondering what it’s going on.
Can anybody explain why it seems like the instanceSetUp isn’t called when I plug device with an internal storage like a phone?
How can I get the filter to work on such devices?

Thank you.

2

> Can anybody explain why it seems like the instanceSetUp isn’t called when

I plug device with an internal storage like a phone?

I haven’t a clue, but my first suspicion is that they are not devices, but
rather explorer plugins.

What does the device manager have to say about them? What about Fltmc?

/Rod

3

This is not a USB storage class device. A volume device object is not created and file system is not mounted.

This is a WPD/MTP device with a user mode UMDF driver.

https://msdn.microsoft.com/en-us/library/windows/desktop/dd319285(v=vs.85).aspx
https://en.wikipedia.org/wiki/Media_Transfer_Protocol

4

Thank you for your prompt responses.

I’ll definitely look at "WPD/MTP device ".

Cheers.