Re: HEADS UP: FreeBSD src repo transitioning to git this weekend

From: Poul-Henning Kamp <phk_at_phk.freebsd.dk>
Date: Mon, 04 Jan 2021 20:43:49 +0000
--------
John-Mark Gurney writes:

> SHAttered[1] (2017) created two valid PDF documents which had the same
> SHA-1 hash.  The issue was that they were able to choose the entire
> document.

Shattered is less impressive when you take into account that you
can stuff as much much garbage into a PDF file as you need, without
affecting the files normal function.

Compact data formats, formats which leave no wiggle-room and do not
offer extension-space for "attic-junk", are much harder to produce
*meaningful* collisions for.

(I take no opinion in where git is on that spectrum.)

This is why I am very sceptical of the recent fashion of "GREASING"
which the TLS WG have invented:  To me that sounds like somebody
is allocating wiggle-room for advanced cryptographic skullduggery.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk_at_FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.
Received on Mon Jan 04 2021 - 19:43:54 UTC

This archive was generated by hypermail 2.4.0 : Wed May 19 2021 - 11:41:26 UTC