From owner-freebsd-security Sun May 2 19: 3: 4 1999 Delivered-To: freebsd-security@freebsd.org Received: from alcanet.com.au (border.alcanet.com.au [203.62.196.10]) by hub.freebsd.org (Postfix) with ESMTP id 39F8915728 for ; Sun, 2 May 1999 19:02:56 -0700 (PDT) (envelope-from peter.jeremy@auss2.alcatel.com.au) Received: by border.alcanet.com.au id <40331>; Mon, 3 May 1999 11:48:10 +1000 Date: Mon, 3 May 1999 12:02:44 +1000 From: Peter Jeremy Subject: Re: Blowfish/Twofish To: adam@homeport.org Cc: freebsd-security@FreeBSD.ORG Message-Id: <99May3.114810est.40331@border.alcanet.com.au> Sender: owner-freebsd-security@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Adam Shostack wrote: >The reason to not use it for passwords is that the function you want >(if you're going to not change the model), is a hash function, not a >block cipher. You'd better let Bob Morris know this :-). Why can't a block cipher (like, say DES) be used for a password hashing function? (I realise that the DES used for Unix password hashing is `tweaked', but that was done solely to prevent people using off-the-shelf DES hardware to crack passwords - the salt can be injected in several other ways). The MD5 description includes a simple algorithm for taking an arbitrary string of bits and feeding it though a block hash function. Exactly the same can be done with a block cipher. Peter To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-security" in the body of the message