[NNTP] RFC 4643 user-pass-char question

[Russ Allbery]

Antti-Juhani Kaijanaho <antti-juhani at kaijanaho.fi> writes:

> RFC 4643 section 3.1 says, in part:
>
>    user-pass-char = B-CHAR
>
>    NOTE: a server implementation MAY parse AUTHINFO USER and AUTHINFO
>    PASS specially so as to allow white space to be used within the
>    username or password.  Such implementations accept the additional
>    syntax (making these two items inconsistent with "token" in Section
>    9.8 of [NNTP]):
>
>    user-pass-char =/ SP / TAB
>
> Now, B-CHAR is defined in RFC 3977, section 9.8 as
>
>    B-CHAR     = CTRL / TAB / SP / %x21-FF

Urgh.

> It seems to me that the NOTE in 4643 § 3.1, particularly the rule
> augmenting user-pass-char is redundant, since SP and TAB are B-CHARs.
>
> My question is, what is this note *intended* to convey?

It's intended to convey that usernames and passwords containing spaces
MAY be supported but are not required to be supported, and servers MAY
reject them, if I recall correctly.

> Draft 9 (June 2005) had P-CHAR instead of B-CHAR.  Draft 10 (August
> 2005) has B-CHAR.  The change seems to have been proposed at
> http://lists.eyrie.org/pipermail/ietf-nntp/2005-August/005840.html,
> but its effect on the NOTE is not discussed.

Hm.  Yeah.  We were talking about charset and I think I missed entirely
the implications for whitespace.

-- 
Russ Allbery (rra at stanford.edu)             <http://www.eyrie.org/~eagle/>