Re: [TLS] What would make TLS cryptographically better for TLS 1.3

Yoav Nir <ynir@checkpoint.com> Tue, 05 November 2013 05:53 UTC

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From: Yoav Nir <ynir@checkpoint.com>
To: Jeff Jarmoc <jeff@jarmoc.com>
Thread-Topic: [TLS] What would make TLS cryptographically better for TLS 1.3
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Date: Tue, 5 Nov 2013 05:53:01 +0000
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Subject: Re: [TLS] What would make TLS cryptographically better for TLS 1.3
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On Nov 4, 2013, at 6:45 PM, Jeff Jarmoc <jeff@jarmoc.com<mailto:jeff@jarmoc.com>> wrote:

And what prevents the client from setting the flag despite not checking?

It's the client's responsibility to validate the server's identity (or not) to the extent it chooses to do so.  It's the server's responsibility to validate the client's identity (or not) to the extent it chooses to do so.

Neither end can take on that responsibility for the other.

Right. This is what the NEA people call "the lying endpoint" problem, and it can't be solved without some pretty rubegoldbergian stuff like trusted computing.

I don't want a client on my machine acting as an agent of the server, informing it that my machine is not configured correctly. Sometimes this information leaks (like when my ClientHello has only SSLv3 and TLS_RSA_EXPORT_WITH_RC4_40_MD5. But beyond that, this is none of the server's business.

Yoav