From: Charles Lindsey (chl@clw.cs.man.ac.uk)
Date: Mon Jun 10 2002 - 06:00:25 CDT
In <Pine.LNX.4.10.10206081428050.22624-100000@spock.peak.org> John Stanley <stanley@peak.org> writes:
>> I see nothing in what the 5.2 note allows that would violate that MUST
>> NOT. The MUST NOT deals with articles that are found unacceptable, not
>> with articles that are deemed to require addition of some headers (as
>> quite explicitly permitted by 8.2.2 step 10).
>It is complicated, so I'll use small words. Your "deemed to require
>addition of some headers" is another way of saying "not acceptable as
>submitted." If the article were acceptable without the addition of these
>optional headers, there is no requirement to add them. Why is the article
>not acceptable without their addition? Well, it's not because the article
>violates this standard. The From-content contains a legal address,
>according to this standard.
>Oh, but maybe the From-content isn't the person actually posting. That
>might require a Sender header, yes? Oops, 6.2 does not require the header,
>it says only what it means when it IS present (not MUST BE), and
>additionally says it SHOULD NOT be present unless the sender (lower case)
>is different from the poster. Well, the injecting agent can know that,
>right? No, once again, "not knowing they are the same" is not sufficient
>proof that they are different, and all the injector can know is that it
>doesn't know.
>The only reason "some headers" are required to be added is because of SITE
>POLICY. The "deemed to require addition of some headers" boils down to
>"this article violates site policy because the From-content is not the one
>known True address for the person I think is posting the article, so site
>policy says I will add a Sender header (or an optional Injector-Info
>header)."
>Under 8.2.2, step 5, we say:
> 5. If the article is rejected, or is otherwise incorrectly formatted
> or unacceptable due to site policy, the posting agent SHOULD be
> informed (such as via an NNTP 44x response code) that posting has
> failed and the article MUST NOT then be processed further.
>So, this article is unacceptable due to site policy -- injector cannot
>determine that the From-content correctly identifies the poster.
>(Remember, nothing in this draft makes it standards-policy that this must
>be done, so it can ONLY be site policy). The posting agent SHOULD be
>informed (not mandatory), but then "the article MUST NOT then be processed
>further".
Wow! What a tortuous line of reasoning; but most ingenious!
Just in case some of you got lost, what John is saying amounts to this:
1. An injecting agent finds an article "unacceptable due to site policy",
but knows a way to make it acceptable (e.g. by adding a Sender-header, or
putting something suitable in an Injector-Info header).
2. Step 5 says the unacceptable article MUST NOT be processed further.
3. Therefore, Step 10, which says it MAY add other headers not already
present, can never be reached, and so it is forbidden from applying the
fix that would make it acceptable again :-( .
Of course, it all boils down to the meaning of "unacceptable". I think
John is trying to say that "unacceptable" is synonymous with "not
acceptable", but English usage is not as simple as that.
In this case, the article is "not acceptable as it stands".
Ergo, it is "conditionally acceptable".
Ergo, it is "acceptable" (since I am sure John would agree that
"conditionally acceptable" is a subset of "acceptable").
Ergo, it is "not unacceptable".
However, John does make a point that the wording of Step 5 is an overkill.
Its prime intent is to ensure that rejected articles SHOULD get reported
with a 4xx response, or similar. It also says that rejected articles MUST
NOT be processed further (which is a tautology I suppose - but note that
everything prior to step 5 is concerned with checking articles for
validity, and everything after Step 5 is for preparing acceptable articles
for injection).
So I have changed it. It now says:
5. If the article is rejected (for reasons given above, or for
other formatting errors or matters of site site policy) the
posting agent SHOULD be informed (such as via an NNTP 44x
response code) that posting has failed and the article MUST NOT
then be processed further.
I don't think that actually changes the meaning of our draft in any way.
-- Charles H. Lindsey ---------At Home, doing my own thing------------------------ Tel: +44 161 436 6131 Fax: +44 161 436 6133 Web: http://www.cs.man.ac.uk/~chl Email: chl@clw.cs.man.ac.uk Snail: 5 Clerewood Ave, CHEADLE, SK8 3JU, U.K. PGP: 2C15F1A9 Fingerprint: 73 6D C2 51 93 A0 01 E7 65 E8 64 7E 14 A4 AB A5