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Date: Thu, 12 Jul 2012 20:58:28 +0400
From: Aleksey Cherepanov <aleksey.4erepanov@...il.com>
To: john-dev@...ts.openwall.com
Subject: Re: Re: Aleksey's status report #10

On Thu, Jul 12, 2012 at 03:43:29PM +0400, Aleksey Cherepanov wrote:
> On Thu, Jul 12, 2012 at 01:16:16PM +0200, Frank Dittrich wrote:
> > On 07/12/2012 12:53 PM, Aleksey Cherepanov wrote:
> > > The opposite problem: how to find the same files? In general before
> > > addition we should compare new file with all existing in the store. I
> > > think I will speed it up with index file (consisted of checksums) in
> > > the store (I will not push that file to avoid conflicts). Though there
> > > is a race condition: two users could add the same file in parallel. So
> > > we could get two equal files. But it does not really matter.
[...]
> > But that would possibly require to rewrite attack descriptions in a
> > similar way, so that they use the checksum instead of the user-supplied
> > file name.
> > And when you checkout the files, they could be renamed to the
> > user-specified file name again.
> 
> I think renaming is not needed. We could just store two names:
> original will be used in properties of attack and checksum will be
> used to refer real file when user runs attack.

Oh, I missed something: if we do not rename files and user wants to
start/modify not his own attack directly then he should pass real
filename to the wrapper, i.e. he should refer to file by sha1sum.

I think we need a syntax to refer to files by their virtual names.
There could be a trick: instead of putting file into attack's subdir
we put there a file with checksum of real file and handle it in
wrapper (when user tries to use that file we substitute sha1sum). It
is like symlinks but more strict and portable (I think git would save
symlink as a symlink in difference to hardlinks, but I doubt that
symlinks from windows and unixes would work together).

Though I found other problem: user could use files with the same name
in one attack. For that files should be in different folders. But when
I would "copy" them into attack's subdir they would collide. Though it
does not seem to be very important. As a simple solution we could ask
user to (interactively) rename file with checksum in store if so. Or
we could rename it automatically.

Other ways to store and use filenames also need some renaming.

Regards,
Aleksey Cherepanov

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