[Cfrg] Question about Spake2

"Scott Fluhrer (sfluhrer)" <sfluhrer@cisco.com> Mon, 17 February 2020 14:51 UTC

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From: "Scott Fluhrer (sfluhrer)" <sfluhrer@cisco.com>
To: Watson Ladd <watsonbladd@gmail.com>
CC: "cfrg@irtf.org" <cfrg@irtf.org>
Thread-Topic: Question about Spake2
Thread-Index: AdXln1O6QRkSk0WrQTiloVKlcp3BEQ==
Date: Mon, 17 Feb 2020 14:50:58 +0000
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Subject: [Cfrg] Question about Spake2
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In your answer to Question 1 of the Round 2 questions, you stated:

The next version will include an option to have M and N based on party
identities, ensuring that an attacker with the ability to solve a
discrete logarithm problem can only compromise a single session per
discrete logarithm computed.

The current draft of Spake2 (draft-irtf-cfrg-spake2-09) does not include this option.  Will there be a version of the draft that would include this option that we could review?

BTW: my personal opinion is that this shouldn't be an option, instead it should be mandatory.  An option means that it is selectable by the protocol, and I distrust forcing the protocol designers to make decisions with security implications that they might not fully understand.