Re: [keyassure] Objective: Restrictive versus Supplementary Models

Paul Wouters <paul@xelerance.com> Thu, 31 March 2011 07:40 UTC

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Date: Thu, 31 Mar 2011 03:42:05 -0400 (EDT)
From: Paul Wouters <paul@xelerance.com>
To: "Richard L. Barnes" <rbarnes@bbn.com>
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Cc: keyassure@ietf.org
Subject: Re: [keyassure] Objective: Restrictive versus Supplementary Models
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On Wed, 30 Mar 2011, Richard L. Barnes wrote:

>> If the attacker injects fake dns records pointing to a fake server, they
>> can include a dane rr.  It only makes the attack slightly harder, doesn't it?
>
> Yes, but as ekr pointed out, injecting fake DANE RRs can only cause the connection to fail, it won't result in the client connecting to a bogus server.   That's why it's RECOMMENDED instead of REQUIRED.

Not if you are a MITM on the wire as well (more star bucks wifi use cases) and
you're directing the user to your own website with a dane rr matching public key.

Paul