Re: [TLS] AES-OCB in TLS [New Version Notification for draft-zauner-tls-aes-ocb-03.txt]

Simon Josefsson <simon@josefsson.org> Sat, 06 June 2015 02:04 UTC

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From: Simon Josefsson <simon@josefsson.org>
To: Russ Housley <housley@vigilsec.com>
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Date: Sat, 06 Jun 2015 04:04:09 +0200
In-Reply-To: <E0C6092D-EFC0-43F9-8807-5D8CE8FF00B8@vigilsec.com> (Russ Housley's message of "Mon, 1 Jun 2015 12:29:19 -0400")
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Subject: Re: [TLS] AES-OCB in TLS [New Version Notification for draft-zauner-tls-aes-ocb-03.txt]
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Russ Housley <housley@vigilsec.com> writes:

> Ilari:
>
>> I think the current plan with EdDSA and related certficates are to reuse
>> ECDSA codepoints, relying on extension (defined by RFC5246) to negotiate.
>
> When we were doing to work for RSA PKCS #1 v1.5, OAEP, and PSS, it was
> unclear whether using the same key pair with all of these schemes
> would lead to trouble.  For this reason, the certificate can allow the
> key pair to be used for just on or all of them.
>
> The same question needs to be asked here.  I hope a more definitive
> answer becomes available this time.

Is that really comparable?  All RSA signature schemes use the same RSA
private keys.  For ECDSA and EdDSA this is not the case.

/Simon