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Re: Security problems in Photuris #2
> From: hugo@watson.ibm.com
> I was not trying to get
> too much into specifications. But, I believe it is clear from the rest
> of my original message that the security of an algorithm is relative to the
> functionality it gives.
>
On the other hand, I am _only_ interested in specifications.
The latter sentence is not obvious. What relation? What does it add to
the specification? (and where would it be put?)
> Notice the words "same required security functionality"; a zero-knowledge
> proof of Hamiltonian cycle is a beautiful protocol but no one has claimed it
> achieves any of the functionalities required by Photuris, like signature,
> encryption, authentication, etc.
>
Actually, in our terms, it is _not_ a protocol, it is an algorithm.
> I don't want to discuss the merits of plain RSA. I am not proposing (or
> recommending) using this mode of RSA. It is just a very natural, practical
> example.
What you have done is specified a "straw man". You admit that it has
none of the functionalities required by the Photuris protocol. Since
Photuris does not recommend its use, and you are unwilling to recommend
its use, why have you wasted our time?
> (And if efficiency is your issue, then let me remark that it
> is *more* efficient if the signed text is no longer than the RSA modulus,
> as the case of Photuris with 155-bit elliptic curve)
>
Another inapplicable "straw man", since Photuris clearly indicates that
the signed text includes more than the shared-secret.
> Bill, please. We are wasting time here. Let's go on. Stubborn defiance will
> not help us.
>
You are correct. You are wasting our time. Stubborn disputation of
irrelevancies will not help us.
> And Phil, where are you????????
>
Surely, if he finds a point that is interesting, he will answer it.
Why do you continue to insist on badgering everyone to answer you?
Well, I've had enough. Let's go on. Does anyone else have something
useful to add to Photuris?
Bill.Simpson@um.cc.umich.edu
Key fingerprint = 2E 07 23 03 C5 62 70 D3 59 B1 4F 5E 1D C2 C1 A2