[NNTP] Re: Issue with IHAVE in RFC

[Clive D.W. Feather]

Julien LIE said:
> I believe there is a major issue with the handling of the 501 answer code.
> 
> According to RFC 3977, the following schema is correct:
> 
>  [S] IHAVE <a b c
>  [C] 501 Bad Message-ID

Correct.

> However, it breaks at least INN and Diablo:  upon receiving 501, their
> feeder will block, disconnect, reconnect and send again the same IHAVE...

Then they are wrong.

> Thus, implementing RFC 3977 breaks current implementations.

I disagree. If you look at RFC 977, section 2.4.3, you will see the same
rule: a syntax error in *any* command results in a 501.

> Of course, the same goes if I send a message-ID whose length is 251
> (which could more likely occur than "<a b c").

Correct.

> As for IHAVE, the only possible answer here is 435; on no account
> should 501 be sent.

I disagree. 435 means "not wanted", not "invalid syntax".

> It appears that a few commands require that no check is done on their
> syntax, and it is not mentioned in RFC 3977.

Nor is it mentioned in RFC 977, nor was it *EVER* mentioned in many years
of discussion leading up to 3977.

> A discussion on news.software.nntp led to the fact that 501 is
> not a valid answer.  See for instance 
> <20090410161411.260$qR at newsreader.com>.

I will look at that.

> Do you have an idea of what it is possible to do as for that issue?

Not easily. You need to decide if you want to work with broken software.

-- 
Clive D.W. Feather          | If you lie to the compiler,
Email: clive at davros.org     | it will get its revenge.
Web: http://www.davros.org  |   - Henry Spencer
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