*BSD News Article 94269


Return to BSD News archive

Path: euryale.cc.adfa.oz.au!newshost.carno.net.au!harbinger.cc.monash.edu.au!munnari.OZ.AU!news.ecn.uoknor.edu!feed1.news.erols.com!cpk-news-hub1.bbnplanet.com!news.bbnplanet.com!news-peer.sprintlink.net!news.sprintlink.net!sprint!uunet!in3.uu.net!206.139.252.5!newsreader.com!not-for-mail
From: curt@kcwc.com (Curt Welch)
Newsgroups: comp.unix.bsd.freebsd.misc,comp.security.unix
Subject: Re: how MD5 works
Date: 23 Apr 1997 15:06:26 GMT
Organization: KCW Consulting
Lines: 19
Message-ID: <8Sqy$a$@NewsReader.Com>
References: <01bc4ecf$0b2c9840$2fa56bc7@jasmin> <1997Apr22.095500.5437@nntp.muohio.edu> <slrn5lq4r0.322.mdw@sol4.ebi.ac.uk>
NNTP-Posting-Host: h4.kcwc.com
Xref: euryale.cc.adfa.oz.au comp.unix.bsd.freebsd.misc:39593 comp.security.unix:33915


mdw@ebi.ac.uk wrote:
> Steven J. Madsen <madsensj@titan.sas.muohio.edu> wrote:
>   1. Raw MD5 is almost certainly faster than the traditional DES-based
>      crypt(3) and probably ought to be slowed down ...

It is.  A comment from the code:

/*
 * and now, just to make sure things don't run too fast
 * On a 60 Mhz Pentium this takes 34 msec, so you would
 * need 30 seconds to build a 1000 entry dictionary...
 */

Then there's a 1000 iteration loop which runs the password,
the salt,  the magic string, and the previous result of the
loop though MD5 in varying orders.

Curt Welch
http://CurtWelch.Com/