Redirect from PostCreate

NTFSD
1

I need to do a redirect in PostCreate but from what I understand returning IO_REPARSE + STATUS_REPARSE will only work from PreCreate should the following work as a solution in Post path?

  1. recieve STATUS_REPARSE in PostCreate
  2. Check for my reparse header and redirect options
  3. Use IoReplaceFileObjectName on FO in callback data to redirect path
  4. Call FltReissueSynchronousIo()
  5. return status from that

Thanks in advance,
Rob

2

Hi Rob,

No, you can return STATUS_REPARSE in postCreate as well…

I’d say you’re better off with returning STATUS_REPARSE in step 4 directly.
This would send it back to the IO manager which would reparse it to the
appropriate place.

If you want to send the request down again, you have a couple of things to
be aware of (that I can quickly think of, there are definitely more):

  1. if the new request is for a different device, you must handle that
    redirection. Then you must make sure there are no requests coming on the
    original device, and if they are then you must redirect them…
  2. you might need to implement a name provider to completely hide the
    redirection from filters above yours.

Any reason returning reparse to the IO manager won’t work ?

Thanks,
Alex.

3

I would prefer to have I/O Manager do the work. I was just misinformed that it wouldn’t on PostCreate. Thanks for the info.