i encypt/decrypt file with filemon
but i have some questions?
my destination is that a trusted process can encrypt/decypt a file
i use ccflushcache and ccpurgecache clean buffer in close and cleanlup callback
but i find when excel save a editing file system show a message “file saved but can not open again please exit and open again” if i exit excel and save it is good have no such question word motepad have no such question.
can somebody help me?thanks
> my destination is that a trusted process can encrypt/decypt a file
You cannot, unless you will create a layered FSD with its own FCBs and caching.
The cache is global for all processes, so, you cannot limit the caching of
cleartext data to the trusted process only.
–
Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
xxxxx@storagecraft.com
http://www.storagecraft.com
first thank Maxim S. Shatskih
my encrypt and decypt have no question and encrypt in WRITE callback decrypt in READcomplete callback
if have cache data is not securyty it can be move to eslewhere
can you explain layered FSD and filemon is not layered FSD filter?
Forget Filemon, it is incorrect and will cause unfrequent crashes under
heavy load due to its very design. Use MS’s filters instead.
Filespy is a classic FS filter by MS. It does not create its own set of
FCBs, instead, it reuses the FCBs by the underlying FSD and filters the IO to
them.
Layered FSD is another, more complex thing. It creates its own FCBs and
thus its own caching (the caching structures are tied to FCBs). With this, you
can decrypt the file for a trusted process only. Without this, you cannot - the
cache will have cleartext data for all processes.
Anyway the idea of “decrypt for trusted process only” is useless. Disk
encryption is only useful to prevent the media/computer stealing. If the device
is not stolen, then the usual ACLs are fine.
–
Maxim Shatskih, Windows DDK MVP
StorageCraft Corporation
xxxxx@storagecraft.com
http://www.storagecraft.com
wrote in message news:xxxxx@ntfsd…
> first thank Maxim S. Shatskih
> my encrypt and decypt have no question and encrypt in WRITE callback decrypt
in READcomplete callback
> if have cache data is not securyty it can be move to eslewhere
> can you explain layered FSD and filemon is not layered FSD filter?
>
thanks
i know filespy and sfilter
i want to finish encrypt/decrypt a file for a trusted process only
in ring 3 it can finish with hook
and now some securypt soft have such tech and i want to have such tech
can you give some suggestions?
I’m starting to side with Dan Burn… give it up.
xxxxx@yahoo.com.cn wrote:
i encypt/decrypt file with filemon
but i have some questions?
my destination is that a trusted process can encrypt/decypt a file
i use ccflushcache and ccpurgecache clean buffer in close and cleanlup callback
but i find when excel save a editing file system show a message “file saved but can not open again please exit and open again” if i exit excel and save it is good have no such question word motepad have no such question.
can somebody help me?thanks
Questions? First check the IFS FAQ at https://www.osronline.com/article.cfm?id=17
You are currently subscribed to ntfsd as: xxxxx@alfasp.com
To unsubscribe send a blank email to xxxxx@lists.osr.com
–
Kind regards, Dejan
http://www.alfasp.com
File system audit, security and encryption kits.
Since my name was invoked, I will ask the first question, you have paid
SysInternals the many thousands of dollars for the license to use Filemon
haven’t you? If you have, you might go back and ask them this question, if
you have not why do you expect us to help you steal software?
–
Don Burn (MVP, Windows DDK)
Windows 2k/XP/2k3 Filesystem and Driver Consulting
Website: http://www.windrvr.com
Blog: http://msmvps.com/blogs/WinDrvr
Remove StopSpam to reply
wrote in message news:xxxxx@ntfsd…
>i encypt/decrypt file with filemon
> but i have some questions?
> my destination is that a trusted process can encrypt/decypt a file
> i use ccflushcache and ccpurgecache clean buffer in close and cleanlup
> callback
> but i find when excel save a editing file system show a message “file
> saved but can not open again please exit and open again” if i exit excel
> and save it is good have no such question word motepad have no such
> question.
> can somebody help me?thanks
>
Please, don’t send the same letter for me.
Thank you very much.
On 5/28/07, xxxxx@yahoo.com.cn wrote:
>
> i encypt/decrypt file with filemon
> but i have some questions?
> my destination is that a trusted process can encrypt/decypt a file
> i use ccflushcache and ccpurgecache clean buffer in close and cleanlup
> callback
> but i find when excel save a editing file system show a message “file
> saved but can not open again please exit and open again” if i exit excel and
> save it is good have no such question word motepad have no such question.
> can somebody help me?thanks
>
> —
> Questions? First check the IFS FAQ at
> https://www.osronline.com/article.cfm?id=17
>
> You are currently subscribed to ntfsd as: xxxxx@gmail.com
> To unsubscribe send a blank email to xxxxx@lists.osr.com
>
Hello
I think you must be mistaken; last time I used filemon it does not perform
encryption and decryption. So alright jokes aside - perhaps you shold get in
touch with OSR about their DMK; it sounds right up your street.
I still dont at all understand how come there seem to be so many posts about
crypto filters. Your thoughts appreciated.
Cheers
Lyndon
wrote in message news:xxxxx@ntfsd…
>i encypt/decrypt file with filemon
> but i have some questions?
> my destination is that a trusted process can encrypt/decypt a file
> i use ccflushcache and ccpurgecache clean buffer in close and cleanlup
> callback
> but i find when excel save a editing file system show a message “file
> saved but can not open again please exit and open again” if i exit excel
> and save it is good have no such question word motepad have no such
> question.
> can somebody help me?thanks
>
I think there are some who want to develop the ‘next great security
application’ or ‘data protection app’ and hope they can make some money.
They seem to say: “We have a copy of the old filemon sources so all we need
is a little tweaking to add encryption”. As each crash occurs, they think
they are almost ready to hit the market - just one more bug fix to go. If
you can display what IRPs and FastIo calls go down the file system stack,
encryption is very simple to add - right? NOT!!! What most don’t seem to
realize is that an active filter is far more difficult than a passive one
with those that alter the data being the most difficult - encryption and
compression specifically.
“Lyndon J Clarke” wrote in message
news:xxxxx@ntfsd…
> Hello
>
> I think you must be mistaken; last time I used filemon it does not perform
> encryption and decryption. So alright jokes aside - perhaps you shold get
> in touch with OSR about their DMK; it sounds right up your street.
>
> I still dont at all understand how come there seem to be so many posts
> about crypto filters. Your thoughts appreciated.
>
> Cheers
> Lyndon
>
> wrote in message news:xxxxx@ntfsd…
>>i encypt/decrypt file with filemon
>> but i have some questions?
>> my destination is that a trusted process can encrypt/decypt a file
>> i use ccflushcache and ccpurgecache clean buffer in close and cleanlup
>> callback
>> but i find when excel save a editing file system show a message “file
>> saved but can not open again please exit and open again” if i exit excel
>> and save it is good have no such question word motepad have no such
>> question.
>> can somebody help me?thanks
>>
>
>
>
hello,Don Burn
my destination is that i want to look a good method to do en/ed a file
i use filemon or sfilter filespy should have no question
my destination is that discuss some tech questions