Rich,
I see your point. If the n/c comprised 8 32-bit words, then you would have a 10% reduction in labor. Does anyone know how long the NIST believes it would take to brute-force a has on a single 512 block?
-Eric
-----Original Message-----
From: Rich Salz [mailto:]
Sent: Friday, September 05, 2003 10:50 AM
To: Eric Gravengaard
Cc: [wss oasis] (E-mail)
Subject: Re: [wss] PasswordDigest in Username profile
> I don't understand your comment. Why would SHA-1( password + nonce + created ) be
> "harder for crackers" than SHA-1( nonce + created + password )?
If I were doing a brute-force attack, I'd have to do the whole SHA1
operation for p/n/c for each guess. If the format is n/c/p, then I can
compute n/c, save the digest state, and then only "restart" the hash
with each password guess.
/r$
--
Rich Salz, Chief Security Architect
DataPower Technology http://www.datapower.com
XS40 XML Security Gateway http://www.datapower.com/products/xs40.html
XML Security Overview http://www.datapower.com/xmldev/xmlsecurity.html
