Re: [TLS] draft-ietf-tls-curve25519-01: Is public key validation necessary or helpful?

Martin Thomson <martin.thomson@gmail.com> Thu, 31 December 2015 19:22 UTC

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Date: Fri, 1 Jan 2016 06:22:00 +1100
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From: Martin Thomson <martin.thomson@gmail.com>
To: Ilari Liusvaara <ilariliusvaara@welho.com>
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Subject: Re: [TLS] draft-ietf-tls-curve25519-01: Is public key validation necessary or helpful?
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On 31 December 2015 at 17:54, Ilari Liusvaara <ilariliusvaara@welho.com> wrote:
> Zero checks can already be unit-tested/interop-tested just as well.


What ekr said applies, but also this:

Yes, you can test that a given implementation does the right checks,
but you won't be checking during normal operation.  If you require
session-hash, then every handshake includes that check and if someone
messes up, the handshake just fails.  That far more visible.