[Okular-devel] md5 hash for annotation file name

[Brad Hards]

On Thursday 11 September 2008 08:16:05 am Albert Astals Cid wrote:
> A Dijous 11 Setembre 2008, Markus Grabner va escriure:
> > I like Ivo's proposal to use QCryptographicHash, which supports MD4, MD5,
> > and Sha1, so these are natural candidates.
>
> It's not an attacker, it's you having two files that collide and gets you
> annotations from one to another.
The probability of a collision (without actually trying to cause one) is 1 in 
2^64 for MD4 or MD5, and 1 in 2^80 for SHA1. I don't think that is too much 
of a problem.

The more general issue is annotations for files that change. If you annotate 
your document, and then edit it, the annotations will be lost.

Brad