[Cryptography] DNSSEC = completely unnecessary?

[Steven Bellovin]

On Nov 6, 2013, at 3:09 38PM, Ben Laurie <ben at links.org> wrote:

> On 6 November 2013 19:13, Kelly John Rose <iam at kjro.se> wrote:
>> On 11/6/2013 10:52 AM, Ben Laurie wrote:
>>> On 6 November 2013 01:48, Paul Wouters <paul at cypherpunks.ca> wrote:
>>>> That's a nonsense argument. Abuse of such powers, unlike the plethora of
>>>> CA certs, would need to be world visible, that is untargetted. It would
>>>> be very very visible. It is a huge win over CAcerts that can target
>>>> individuals with specifically crafted signed certs.
>>>> 
>>>> With dnssec, if the Government of Canada causes my nohats.ca to be
>>>> modified (appear red on your above map), then my domain's public
>>>> information changes. I would notice that. This is not an invisible
>>>> MITM like some CA cert injection.
>>> 
>>> How did DNS get this magic un-MITM-able property?
>>> 
>>> Surely if the GoC wants to cause nohats.ca to be modified, for some
>>> specific target(s), they can do that?
>> 
>> He didn't say it isn't MITM-able. He said that it cannot do so
>> invisibly. In his model Eve would be able to perform a MITM attack, but
>> it would be immediately apparent to any party since the public
>> information would have to change.
> 
> I got what he said. Its not true.

Correct.  I showed some ways of doing very targeted DNS attacks in 1995,
based on work from 1990-1991.  "Attacks only get better; they never
get worse."  And I didn't even consider things like p0wned routers or
hosts on the LAN.


		--Steve Bellovin, https://www.cs.columbia.edu/~smb