RE: [wss] PasswordDigest in Username profile

["Eric Gravengaard" <eric@reactivity.com>]

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:rsalz@datapower.com]
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
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