WebApp Sec mailing list archives
Re: Securing file access
From: Ido Rosen <ido () cs uchicago edu>
Date: Tue, 28 Sep 2004 16:47:30 -0500
I have written an app with a friend which does just this. It should be IIS compatible. It is written in PHP, though you are welcome to create an ASP version (please send me a copy of your version if you are okay with releasing it for free). It is available at: http://www.sf.net/projects/teraband "Teraband: Download Server Administrator". While that version (the release) does not directly support user/pass-based authentication, everything is there to support it. It demonstrates how to securely retrieve a file (from outside of the web directory), and transfer it several blocks at a time to the remote end, recording bandwidth usage, etc. The code also demonstrates solutions to some problems you will encounter while developing your application, since it is essentially the same objective, except in Teraband's case the objective is to not allow file access once a limit is reached. Go check it out. You can read the source live off of SourceForge CVS if you want, or download a release and play with it. Should you have any questions about Teraband, feel free to email me. Best wishes, Ido On Tue, Sep 28, 2004 at 02:06:19PM -0400, robbin wrote:
Script the retrieval and just put the file out there, basically you have to open the file and put it to the web page with the appropriate header so that the user will be prompted for a download, save as pop box. I've done this in perl, print header(-type=>"application/x-download", -attachment=>"$fullyqualifiedfilename", ); open (DWNLD,"<$file"); binmode(DWNLD); $/ = undef; my $zip = <DWNLD>; close (DWNLD); binmode(STDOUT); print $zip; Hope example helps. Robbin John M. L. wrote:I have a project that involves a members only area on web page on IIS. The members' only area is secured by a database (MS Access) so users are authenticated by their name and some MD5 hash etc. I need to allow files (mostly PDFs) for download to authenticated users only. In my opinion this means that the files can not be stored in any www accessible folder (regardless of any renaming convention etc, I absolutely cannot have someone guess a file name to download). In order to access the files, the database would link a file to a unique id, so a page that validates the user would then give access to the file stored outside of the www on the server. Now, this is where the real question lies. How is this possible since the files are not in a www accessible path, since a mere link to a file won't due. Any thoughts would be welcome. If I'm going about this completely wrong that would be nice to no too :) Forgive me if the answer is simple, I'm a Linux fan and haven't used IIS etc for years. One more note: IIS, MS Access and VBScript are not my technologies of choice, but merely what I was given to work with. I also have very limited control over administering IIS. John www.recaffeinated.com-- O|||||||O Silly Boys, Jeeps are for girls.
-- email : ido () ieee org / ido () cs uchicago edu jabber : ido () rosen md pgp : http://www.cs.columbia.edu/~ido/pgp
Current thread:
- Re: Securing file access, (continued)
- Re: Securing file access Saphyr (Sep 29)
- Re: Securing file access Jason Merriman (Sep 29)
- Re: Securing file access Ian (Sep 29)
- Re: Securing file access Subs (Sep 30)
- RE: Securing file access Koen Vingerhoets (Sep 29)
- Re: Securing file access PD9 Software (Sep 29)
- Re: Securing file access Ben Timby (Sep 29)
- Re: Securing file access robbin (Sep 30)
- Re: Securing file access James Barkley (Sep 30)
- Re: Securing file access robbin (Sep 28)
- Re: Securing file access Ido Rosen (Sep 29)
- RE: Securing file access BĂ©noni MARTIN (Sep 28)
- RE: Securing file access Calderon, Juan Carlos (GE Commercial Finance, NonGE) (Sep 29)
- RE: Securing file access Booth, Simon (Sep 29)
- RE: Securing file access Shields, Larry (Sep 29)
- RE: Securing file access Beckner, Chad A (Sep 30)
- Re: Securing file access Saphyr (Sep 29)