In my data-modified filter,I must handle a problem:
In my filter is On,I do data-modify.In my filter is Off,I do not
data-modify.
And,I can set the filter is On or Off by my user application(IOCTL).
As you know,the cache.So,I must clear the cache if needed.I have did it,it
works well(that’s not complex).
But,when I take remote file(UNC) into account,I find it’s a difficult
problem.
To a local file,when my filter is On,I can Roll a exclusive Createfile with
FILE_READ_DATA.if ACCESS_DENY,I can say there are no handles for it(I don’t
care CreateFile without DATA access).
But to a remote file,I can’t roll a exclusive CreateFile,because maybe other
clients(Computer) have opened the file.So,evenif it returns ACCESS_DENY,I
can’t say there no handles for it in my local system.
How can I do it?
This problem is important,because if there are handles for it,the process
will get data by the handle.
I think if I can’t get it(There are no handles for the file),maybe I can
Deny these request in FastWrite,FastRead nad Read,Write.