Re: ISSUE: treatment of POSTED in proto articles

["Charles Lindsey" <chl@xxxxxxxxxxxxxxxx>]

Sory, I omitted to change the Subject line to include "ISSUE" the first
time I posted this.

In <K7pJ01.5Dv@xxxxxxxxxxxxxxxx> "Charles Lindsey" <chl@xxxxxxxxxxxxxxxx> writes:

In <87prmxrms3.fsf@xxxxxxxxxxxxxxxxxxxxx> Russ Allbery <rra@xxxxxxxxxxxx> writes:

>"Charles Lindsey" <chl@xxxxxxxxxxxxxxxx> writes:

>> 3.4.1.  Proto-articles
>>
>>    A proto-article has the same format as a normal article except that
>>    the Injection-Info and Xref header fields MUST NOT be present; the
>>    Path header field MUST NOT contain a "POSTED" <diag-keyword>; and any
>>    of the following mandatory header fields MAY be omitted: Message-ID,
>>    Date, and Path.  In all other respects, a proto-article MUST be a
>>    valid Netnews article.  In particular, the header fields which may be
>>    omitted MUST NOT be present with invalid content.
>>
>> I am worried about that 'MUST NOT contain a "POSTED" <diag-keyword>'. It
>> would cause no interoperability problems and cause no significant harm,
>> and hence a "MUST" cannot be justified under RFC 2119. Nothing breaks if
>> two "POSTEDs appear in one Path.  Indeed, it could arise legitimately in
>> multiple injection "after the fact", and in other exotic gatewaying
>> situations.
>>
>> Yes, some s[pc]ammers will preload the Path so as to disguise the true
>> origin of an article (which is indeed why POSTED was invented), but that
>> is a matter to be taken up by the netkops rather than the protocols. And
>> I would prefer to preserve all evidence left over from previous Paths in
>> order to facilitate bebugging of broken gateways, etc.
>>
>> So, at the most, it ought to be a SHOULD, and I would be happy to omit
>> it altogether. Note that whatever change is made here, corresponding
>> changes would be needed in 3.4.2 and 3.5.2 Step 2.

>This is also a protocol change and should therefore be a separate issue.
>I'm inclined to agree with you that MUST isn't justified here and SHOULD
>is more appropriate.  I think we already talked about this before,
>although I haven't gone back and looked.

OK, here it is. I note that you agree that MUST is too strong.

However, I think SHOULD (and perhaps even MAY) is too strong. The protocol
use to prevent loops is not affected by this change. But the Path is also
important for diagnosing the cause of loops (not necessarily
non-terminating ones) such as those caused by peculiar gatewaying, and for
spotting trollers who try to disguise the source of their articles.

So seeing two 'POSTED's in a Path should immediately raise alarm bells
(even though it may occasionally turn out to have a benign explanation).
But if duplicate 'POSTED's are removed, then no alarm bells will be
heard. So leave them in, and let the Debuggers and the Netkops take care
of them.

In either case, there would be consequential changes elsewhere, as noted.

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