Subject: [Emu] RFC 7170 Erratum 5844

From: Eliot Lear <[email-masked]>
Date: Wed, 22 Jan 2020 14:48:49 +0100

If we accept erratum 5845, then it seems only natural that we should accept this erratum as well.

> Section 3.3.1 says:
> 
>    EAP method messages are carried within EAP-Payload TLVs defined in
>    Section 4.2.10.  If more than one method is going to be executed in
>    the tunnel, then upon method completion, the server MUST send an
>    Intermediate-Result TLV indicating the result.
> 
> It should say:
> 
>    EAP method messages are carried within EAP-Payload TLVs defined in
>    Section 4.2.10.  Upon method completion, the server MUST send an
>    Intermediate-Result TLV indicating the result.
> 
> Notes:
> 
> Description of whether Intermediate-Result TLV is supposed to be used in the case where only a single inner EAP authentication method is used. Section 3.3.1 says "more than one method is going to be executed in the tunnel, then upon method completion, the server MUST send an Intermediate-Result TLV indicating the result", Section 3.3.3 says "The Crypto-Binding TLV and Intermediate-Result TLV MUST be included to perform cryptographic binding after each successful EAP method in a sequence of one or more EAP methods", 4.2.13 says "It MUST be included with the Intermediate-Result TLV to perform cryptographic binding after each successful EAP method in a sequence of EAP methods", Annex C.3 shows an example exchange with a single inner EAP authentication method with use of Intermediate-Result TLV.
> 
> It looks like the majority of the places discussion this topic implies that there is going to be an Intermediate-Result TLV after each inner EAP authentication method and the text in 3.3.1 is the only clear case of conflicting (or well, at least misleading if one were to claim it does not explicitly say MUST NOT for the one inner EAP authentication method case). As such, I'd conclude the Intermediate-Result TLV is indeed going to be exchanged after each EAP authentication method and the proposed text change to 3.3.1 covers that.