Hi,
I am writing a Volume Class upper filter to encrypt my logical drive
D:.My OS is Win2K.FileSystem on D: is FAT32.
I modified DDK/src/general/toaster/filter example.In processing
IRP_MJ_WRITE,every byte encrypted with its value +2;in IRP_MJ_READ
completing routine,every byte decrypted with its value -2.
At first,I encrypt the whole D: partition,including Boot sectors,FAT and
clusters used in data area.
Then I installed the driver,it created a FiDO and attached it to
\Device\HarddiskVolume2.OSR’s DeviceTree reported
----DEV:\Device\HarddiskVolume2
|ATT:(unnamed)-\Driver\Volumefilter
|[FT] File System:(unnamed)-\Filesystem\Fastfat.
Every thing seems to be correct when i open/modify a file with app such
as Note.exe.
Now the problems are:
1.When I try to format D:,windows reported with message"windows can’t
complete formating!".
2.When I delete a file existed in D:,other files and dictionary’s name
become strange symbol
such as “.”.
To the second problem,I think because the FAT has been modified but the
filter driver didn’t
interrupt the WRITE request to FAT.But Why?I have thought that the filter
driver should interrupt
all I/O requests toward the D: partion.
Now I doubt that the Volume class filter will interrupt all I/O requests
toward corresponding
partion.Am I thinking right?I do something wrong?
Any help would be greatly appreciated.
Thanks.
ziking_hu