Re: [OAUTH-WG] [Gen-art] Gen-ART Telechat review of draft-ietf-oauth-v2-bearer-22.txt

[Mike Jones <[e-mail]>]

For clarity of discussion, the definition in question is:
     b64token    = 1*( ALPHA / DIGIT /
                       "-" / "." / "_" / "~" / "+" / "/" ) *"="

Note that b64token is a liberal syntax intended to permit base64 encoded content (hence the inclusion of the "+" and "/" characters and the optional trailing "=" characters), base64url encoded content (hence the inclusion of the "-" and "_" characters) and other URL-safe productions (hence the inclusion of the "." and "~" characters).

Its use is definitely not intended to be restricted to base64 encoded content, per RFC 4648. If it were so restricted (by not allowing ".", for instance), this would exclude the use of JWTs as bearer tokens, for instance, which is something we *definitely* want to allow.

As a result, I don't think adding a reference to RFC 4648 is either necessary or appropriate.

Julian may be able to provide more background.

				Best wishes,
				-- Mike

-----Original Message-----
From: Alexey Melnikov [mailto:[e-mail]] 
Sent: Tuesday, July 17, 2012 10:02 AM
To: Julian Reschke; Mike Jones
Cc: The IESG; General Area Review Team; [e-mail]; [e-mail]; Stephen Farrell
Subject: Re: [Gen-art] [OAUTH-WG] Gen-ART Telechat review of draft-ietf-oauth-v2-bearer-22.txt

On 17/07/2012 17:40, Julian Reschke wrote:
> On 2012-07-17 18:10, Mike Jones wrote:
>> FYI, the b64 token definition is identical to the one in 
>> draft-ietf-httpbis-p7-auth-20.  If it works there, it should work for 
>> OAuth Bearer.
>> ...
>
> +1; not every constraint needs to be expressed in the ABNF. "b64token" 
> is here so recipients can parse the header field; it's up to the auth 
> scheme to state what the addition constraints are; and that can happen 
> in prose.

I didn't say that it has to be expressed in ABNF (although I obviously wouldn't mind). I would like an ABNF comment pointing to the document which defines base64.