A crazy thought?

[Allen]

Two birds with one shot. :)

Ali, Saqib wrote:

> I am not sure what you are trying to achieve. The CA never has your
> private key. They are just signing a X.509 certificate that holds your
> public key. This way they are vouching that that you own the public.
> Even if you subpoena a CA they won't be able to decrypt any
> information encrypted with your public key.
> 
> So having a separation-of-duty is not providing any additional security.
> 
> Can you please elaborate on you are trying to achieve?

I never said that the CA had your private key, only that they 
could validate an open message came from whomever held the 
private key associated with a given public key.

I like going back to historical instances to illustrate issues 
because people can read about them from second sources and 
perhaps get clues about the issue they might not of otherwise.

In this case I'll refer to a commonly acknowledged observation 
that the biggest financial backer of the Communist Party, USA, in 
the 1950s was the FBI. Another instance of a similar sort is that 
in many cases during the anti-Vietnam war years, the people 
advocating violent actions turned out to be paid agents of the 
FBI and other government agencies.

And a third scenario to consider is the capture of German spies 
by the British and them using them to send both bogus and real 
intelligence back to their masters.

PKI and other similar structures are an attempt to maintain 
confidentiality between two parties that are not present in the 
same room while at the same time assure each other that they are 
indeed talking to who they think they are.

In the case of the FBI agents they were not talking to whom they 
though they were. With the German spies, they were, but the spies 
had been suborned with threats of the noose if they did not comply.

Same problem, two different expressions. How do you trust who you 
are talking to is the person they represent themselves as? It is 
almost a side issue whether anyone else is privy to the contents 
of the conversation, important to prevent misuse and fraud by 
others, but not central to the first point: Identification.

In a private e-mail a suggestion was made that it might be 
possible for a CA to issue a second certificate alleging it to be 
yours but in fact it belonged to someone else. In this case which 
is the real you as represented by the conflicting certificates?


Then Ian G wrote:

[snip]

> As a side note, outside the cryptography layer, there are legal, 
> contractual, customary defences against the attacks that you outline.

Ah, yes, the rule of law. Well, I think we've seen enough with 
the Real Innocence Project validating that people are put to 
death with customary "legal" processes and that Guantanamo Bay 
exists to say that if the law is your only protection you need 
help in a big way if someone gets a burr up their butt about you.

My goal in this discussion examine how we can keep the underlying 
issues clear and utilize tools, like cryptography, to assist us 
in achieving well founded trust relationships.

Best,

Allen

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