EldoS | Feel safer!

Software components for data protection, secure storage and transfer

Really virtual

Also by EldoS: CallbackFilter
A component to monitor and control disk activity, track file and directory operations (create, read, write, rename etc.), alter file data, encrypt files, create virtual files.
#19669
Posted: 04/05/2012 08:12:56
by Felipe Polo-Wood (Standard support level)
Joined: 04/05/2012
Posts: 1

We need to serve images to an application that only supports UNC. The problem is that for security and efficiency, we cannot provide a listing of the image files (1. we don't want people to just randomly browse images, even if they have security rights, 2. The calling application supports only filenames, no paths, so all the files need to be in one folder and since these images don't really exist we won't know what they are until they are requested, I mean, we are really virtual).
So, the calling application will attempt to open a file, we will then desconstruct a key out of the file name, search for the information, build an image and make it available for the reads until the file is closed. I guess that is standard stuff and has been done many times using your product. But, while browsing the documentation and several of the topics in this forum, it seems that the enumeration of the directory would be a problem. Using a different driver (which should remain nameless :), we were able to get away with the FindFiles always returning an empty directory, is that an option with CBFS? In your experience, is this the right approach? Any suggestions? Thank you!
#19670
Posted: 04/05/2012 08:34:58
by Volodymyr Zinin (EldoS Corp.)

Hello Felipe,

I don't see any problem in your scenario. You can easily check it by slightly modifying the Mapper sample. In its OnEnumerateDirectory callback set to always return "no files" and try to open an existing "mapped" file by the use of your application.

BTW some applications can check the presence of a file before its opening by the use of the system API call FindFirstFile() with the mask which corresponds strictly to the file name. So in this case your OnEnumerateDirectory callback must report information about this file.

Reply

Statistics

Topic viewed 622 times

Number of guests: 1, registered members: 0, in total hidden: 0




|

Back to top

As of July 15, 2016 EldoS Corporation will operate as a division of /n software inc. For more information, please read the announcement.

Got it!