Re: Syntax validation of articles by injecting agents

In <[email protected]> Russ Allbery <[email protected]>=
 writes:

>Julien =C3=89LIE <[email protected]> writes:

>> RFC 5537 mentions that an injecting agent MUST reject any proto-articl=
e
>> that is not syntactically valid as defined by RFC 5536.

>In retrospect, I suspect that should either have been a SHOULD or it
>should have singled out the netnews-specific restrictions.  I don't thin=
k
>anyone pointed out at the time that it would mean rejecting all non-MIME
>messages, and I suspect we would have changed it if we'd realized that a=
s
>fairly impractical.

Eh? How does it imply that? If there are no Content-* headers, then there
is no requirement for MIME-Version.

>The point was more to reject messages with syntactically invalid
>Newsgroups headers and whatnot.

>> And what if a news reader generates an incorrect User-Agent: header
>> field?  or if it always adds a tail-entry which is not a path-nodot
>> in Path:?  All its posts will be rejected by a RFC-compliant injecting
>> agent...
>> It it the intention?

>I wonder how many user agents generate invalid Path headers.  Hm.

But aren't injecting agents allowed to remove a Path header that is
received? For sure, many of them routinely do. In any case, fixing (or
removing) a broken header is always a way out of the problem.

>I have a hard time justifying rejecting articles on the basis of syntact=
ic
>problems in purely informational headers like User-Agent.

>> I quite understand that it would help to have better compliant
>> articles.  For instance, rejecting articles with "all" in their
>> distribution list.

>That, at least, the user probably has some control over.


>> How can we handle that MUST without hurt?

Well any leniency should only apply to things the user cannot control. Bu=
t
the world will not suddenly end if some implementation usees Common Sense
in cases that will do no practical harm.

--=20
Charles H. Lindsey ---------At Home, doing my own thing------------------=
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