cant store article: bogus Xref: header in INN 2.5 ?

[Russ Allbery]

Julien ÉLIE <julien at trigofacile.com> writes:

> Another point:

>    xref            =  "Xref:" SP *WSP server-name
>                       1*( FWS location ) *WSP CRLF

> I plan on allowing FWS instead of *WSP before server-name.  As it happens
> when parsing an already injected/accepted article, I believe it does no
> harm (contrary to nnrpd, acting as an injecting agent; and anyway, it will
> not accept articles already containing an Xref: header field).

That's certainly fine for ease of maintenance.  The only reason why the
grammar specifies *WSP there instead of [FWS] was to follow the general
dictate of section 2.2:

   o  Every line of a header field body (including the first and any
      that are subsequently folded) MUST contain at least one non-
      whitespace character.

         NOTE: This means that no header field body defined by or
         referenced by this document can be empty.  As a result, rather
         than using the <unstructured> syntax from Section 3.2.5 of
         [RFC5322], this document uses a stricter definition:

   unstructured    =  *WSP VCHAR *( [FWS] VCHAR ) *WSP

         NOTE: The [RFC5322] specification sometimes uses [FWS] at the
         beginning or end of ABNF describing header field content.  This
         specification uses *WSP in such cases, also in cases where this
         specification redefines constructs from [RFC5322].  This is
         done for consistency with the restriction described here, but
         the restriction applies to all header fields, not just those
         where ABNF is defined in this document.

which in turn was because we believed that some software would react
poorly to headers that had no non-whitespace on the first line of the
header body, and also because it's otherwise very easy to lose the space
after the colon (which we knew some software required).

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

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