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Help on Minispy File System Minifilter Driver.

jay96612jay96612 Member Posts: 44
edited September 2020 in NTFSD

I want to monitor any I/O and transaction activity that occurs in the system. I am using minispy as example. Can I use minispy such a way that I don't need to explicitly attach Drive Letter to minispy .?
I want to monitor on the whole file system.
In user mode application: we attach drive letter to minispy using following command to start monitor on that drive:

/a DriveLetter

so any way to do this without explicitly attaching drive letter.?

Thanks. Any help will be much appreciated.


  • 0xrepnz0xrepnz Member Posts: 51

    Well all "/a" does it to simply call FilterAttach. You can modify the user side of minispy to call to FilterAttach yourself during initialization if you want too.. Also you can enumerate and attach to all volumes with FilterVolumeFindFirst

    You can also modify the minispy minifilter to attach in kernel mode.. (FltEnumerateVolumes + FltAttachVolume)

    - Ori Damari
  • Scott_Noone_(OSR)Scott_Noone_(OSR) Administrator Posts: 3,442

    Minispy sets the "suppress automatic attachment" bit in the instance flags:

    ;Instances specific information.
    DefaultInstance         = "Minispy - Top Instance"
    Instance1.Name          = "Minispy - Middle Instance"
    Instance1.Altitude      = "370000"
    Instance1.Flags         = 0x1          ; Suppress automatic attachments
    Instance2.Name          = "Minispy - Bottom Instance"
    Instance2.Altitude      = "361000"
    Instance2.Flags         = 0x1          ; Suppress automatic attachments
    Instance3.Name          = "Minispy - Top Instance"
    Instance3.Altitude      = "385100"
    Instance3.Flags         = 0x1          ; Suppress automatic attachments

    Set Flags to zero and you'll automatically attach.


  • jay96612jay96612 Member Posts: 44

    @Scott_Noone_(OSR) Thank You very much for the info.

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