From: Mike Hommey <mh@glandium.org>
Date: Fri, 03 Mar 2017 01:50:47 GMT
Subject: Re: SHA1 collisions found
Message-ID: <20170303015047.p4lpkdzp4hbpz5vi@glandium.org>
In-Reply-To: <CA+55aFzdJcFZQdJ78rvZ92nNZRsKfcUKMCiXwTVYR34JAuznrA@mail.gmail.com>

On Thu, Mar 02, 2017 at 02:27:15PM -0800, Linus Torvalds wrote:
> On Thu, Mar 2, 2017 at 1:54 PM, Joey Hess <id@joeyh.name> wrote:
> >
> > There's a surprising result of combining iterated hash functions, that
> > the combination is no more difficult to attack than the strongest hash
> > function used.
> 
> Duh. I should actually have known that. I started reading the paper
> and went "this seems very familiar". I'm pretty sure I've been pointed
> at that paper before (or maybe just a similar one), and I just didn't
> react enough for it to leave a lasting impact.

What if the "object version" is a hash of the content (as opposed to
header + content like the normal git hash)?

Mike