phc-discussions - Re: [PHC] PHC output specifics

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Sun, 15 Mar 2015 17:19:12 +0000
From: "Zooko O'Whielacronx" <zookog@...il.com>
To: discussions@...sword-hashing.net
Subject: Re: [PHC] PHC output specifics

The stringprep standard (http://www.ietf.org/rfc/rfc3454.txt) was
designed to address basically this same issue: that the user intends
two strings to be the same, but that the two strings accidentally get
a different binary representations from one another.

Encoding and normalization are only the first two tips of the iceberg.

I don't know if stringprep comes with more baggage than it is worth,
but at least it is a standard is written down. We could recommend that
implementors specify a stringprep profile to apply to strings before
encoding and hashing. Here's an example of an authentication mechanism
specifying a stringprep profile:

http://tools.ietf.org/html/rfc4505#section-3

It fits on a single page on my screen, and it addresses a lot more
tips of the iceberg that implementors otherwise wouldn't have thought
of.

Regards,

Zooko