phc-discussions - Re: [PHC] Upgrade HKDF to HKDF2?

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 linux-cve-announce 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]

Message-ID: <alpine.DEB.2.10.1403101031540.13698@debian>
Date: Mon, 10 Mar 2014 10:38:16 +0100 (CET)
From: Stefan.Lucks@...-weimar.de
To: discussions@...sword-hashing.net
Subject: Re: [PHC] Upgrade HKDF to HKDF2?

On Sun, 9 Mar 2014, Bill Cox wrote:

> for(i = 0; i < passwordLength; i += 256) {
>    for(j = 0; j < 256; j++) {
>        buf[i] = password[(i + j) % passwordLength];
>    }
>    Hash_Update(hashCtx, buf, 256);
> }

Welcome password collisions!

Consider, e.g., passwords such as "abcd", "abcdabcd", "abcdabcdabcd" ...

Stefan

------  I  love  the  taste  of  Cryptanalysis  in  the morning!  ------
     <http://www.uni-weimar.de/cms/medien/mediensicherheit/home.html>
--Stefan.Lucks (at) uni-weimar.de, Bauhaus-Universität Weimar, Germany--