john-users - Re: quite fast MD5 hashing implementation

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Date: Wed, 24 Sep 2008 11:33:02 +0200
From: "Slythers Bro" <slythers@...il.com>
To: john-users@...ts.openwall.com
Subject: Re: quite fast MD5 hashing implementation

in md4
#define FF(a, b, c, d, x, s) { \
    (a) += F ((b), (c), (d)) + (x); \
    (a) = ROTATE_LEFT ((a), (s)); \
  }


i predict a very good reverse trick in md4, where in md5 i failed
because of the rotation before an addition it was impossible to
reverse deeper
it miss in md4

in md5
#define FF(a, b, c, d, x, s, ac) \
  {(a) += F ((b), (c), (d)) + (x) + (unsigned int)(ac); \
   (a) = ROTATE_LEFT ((a), (s)); \
   (a) += (b); \
  }

in my opinion the two last line are the real "chaos" in md5