PlayStation 3 predicts next US president

James A. Donald jamesd at
Sun Dec 2 02:11:00 EST 2007

William Allen Simpson wrote:
 > Apparently, you never read the original rationale for
 > MD5.  It still does what it was intended to do....

MD5 was intended to identify the thing being hashed
uniquely.  If it is possible to produce multiple
plausible human readable texts that say different things
yet give the same MD5 hash, it does not do what it was
intended to do.

James A. Donald:
 >> If it is a certifier, these are not "its" documents.

William Allen Simpson:
 > If it is a certifier, it damn well better be its own
 > documents!

A notary is a certifier.  Have you ever seen a notary
read the stuff he notarizes, let alone generate it?

 > Look at the original message:
 >  This implies a vulnerability in software integrity
 >  protection and code signing schemes that still use
 >  MD5.

Suppose you sign a contract - by signing the MD5 hash of
the contract.  Unfortunately the guy who prepared the
contract prepared two slightly different contracts, one
of which is more favorable to him and less favorable to
you than the one you actually signed.  Both contracts
have the same MD5 hash.

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