Re: [Acme] Repeated tokens for different challenges in same authorization

Russ Housley <housley@vigilsec.com> Mon, 13 February 2017 20:20 UTC

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From: Russ Housley <housley@vigilsec.com>
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Date: Mon, 13 Feb 2017 15:20:01 -0500
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Subject: Re: [Acme] Repeated tokens for different challenges in same authorization
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> In the WGLC thread, Russ asked:
> 
>> In Section 6.5, should the example use different challenges for "http-01", "tls-sni-02", and "dns-01"?
> (https://ietf-wg-acme.github.io/acme/#rfc.section.6.5)
> 
> I assume you meant "token" here, and no, I think the token can be the same across multiple challenges for the same authorization. Boulder (Let's Encrypt's implementation) doesn't currently do this, but will in the future. If you think there's a risk in this, please let us know!

I do not think it is a risk with the authorizations that have been defined. I was wondering about a situation where a client make a mistake.  If a client tries to fulfill one of the authorizations and for some reason is unable to do so completely, and then moves to another authorization, can the half-done first authorization cause a problem.

Russ