phc-discussions - Re: [PHC] Specification of a modular crypt format

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: <20150926174617.GA14539@openwall.com>
Date: Sat, 26 Sep 2015 20:46:17 +0300
From: Solar Designer <solar@...nwall.com>
To: discussions@...sword-hashing.net
Subject: Re: [PHC] Specification of a modular crypt format

On Sat, Sep 26, 2015 at 08:34:53PM +0300, Solar Designer wrote:
> So for (ye)scrypt we could have:
> 
> $7X$Nr$salt$hash
> 
> or:
> 
> $7X$Nrhp$salt$hash
> 
> or:
> 
> $7X$Nrhpftg$salt$hash
> 
> where "N" is encoding of N-1,

I meant: where "N" is encoding of log2(N)-1.

> "r" is encoding of r-1, "h" is encoding of
> have-1, and "p", "f", "t", or/and "g" are encodings of p-2, flags-1,
> t-1, g-1 if those are non-default and indicated as present in "have".

The "-1" for log2(N) and r is primarily to make the too small invalid
values non-encodable.  For the rest (the optional parameters), the "-2"
and "-1" are primarily to ensure deterministic encoding.

Alexander