Re: [Trans] DNSSEC also needs CT

Stephen Kent <kent@bbn.com> Thu, 22 May 2014 18:12 UTC

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Date: Thu, 22 May 2014 14:12:39 -0400
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Subject: Re: [Trans] DNSSEC also needs CT
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PHB,
> On Thu, May 22, 2014 at 1:21 PM, Stephen Kent<kent@bbn.com>  wrote:
>
>> PKIX, per se, does not have the trust problems that seem to motivate
>> CT; the Web PKI does. That PKI has always had a serious problem because
>> any TA can issue a cert for any Subject, irrespective of the Subject name.
>> because DNSSEC intrinsically incorporate the equivalent of PKIX Name
>> Constraints, it does not suffer from that specific problem. That's not to
>> say that mis-issuance is not possible in DNSSEC, but rather that its
>> effects are more limited.
> On the contrary, it has a rather more severe problem in that the names
> can be reassigned by the upstream zone.
is that really more "serve" than an ability to issue a credential
for ANY name, as in the Web PKI?
> Depending on your application, this might not matter. But if you want
> to try hooking an enterprise PKI off a DNSSEC system then this matters
> a great deal. I am sure that Google would not want to find that
> VeriSign could direct their infrastructure to change configuration by
> issuing a fraudulent DNSSEC signed zone.
A large, competent enterprise (if that's not an oxymoron) can run its own
PKI w/o using DNSSEC. This seems like a red herring.
> Come to that, that particular sort of compromise is the type of thing
> that we spent a lot of time and effort trying to put out of reach when
> I worked at VRSN. I don't want to have someone's private key because I
> don't want to be accused of losing it.
no argument there.
> Don't think of CT in this case being something to solve a problem
> faced by DNSSEC users, instead think of it as something that enables
> use for problems where it is otherwise unsuited.
That's a very confusing last phrase.
> The other major advantage is that it provides a tool to avoid some of
> the cryptographic lock in problems that are causing certain countries
> to cause issues in ICANN. You don't have to agree with their analysis
> to find value in addressing the concerns.
I understand their concerns. But the lack of a well-articulated 
architecture
for CT, much less a CT for DNSSEC, makes it hard for me to gauge whether
this is a good idea.

Steve