Possibly questionable security decisions in DNS root management

[Greg Rose]

On 2009 Oct 19, at 9:15 , Jack Lloyd wrote:

> On Sat, Oct 17, 2009 at 02:23:25AM -0700, John Gilmore wrote:
>
>> DSA was (designed to be) full of covert channels.
> And, for that matter, one can make DSA deterministic by choosing the k
> values to be HMAC-SHA256(key, H(m)) - this will cause the k values to
> be repeated, but only if the message itself repeats (which is fine,
> since seeing a repeated message/signature pair is harmless), or if one
> can induce collisions on HMAC with an unknown key (which seems a
> profoundly more difficult problem than breaking RSA or DSA).

Ah, but this doesn't solve the problem; a compliant implementation  
would be deterministic and free of covert channels, but you can't  
reveal enough information to convince someone *else* that the  
implementation is compliant (short of using zero-knowledge proofs,  
let's not go there). So a hardware nubbin could still leak information.

Greg.

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