Re: WGLC p1: MUST fix Content-Length?

Alex Rousskov <rousskov@measurement-factory.com> Wed, 01 May 2013 07:38 UTC

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Date: Wed, 01 May 2013 01:37:29 -0600
From: Alex Rousskov <rousskov@measurement-factory.com>
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To: Willy Tarreau <w@1wt.eu>
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Subject: Re: WGLC p1: MUST fix Content-Length?
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On 05/01/2013 01:22 AM, Willy Tarreau wrote:
> On Tue, Apr 30, 2013 at 11:53:28PM -0600, Alex Rousskov wrote:
>> Hello,
>>
>>     When talking about a Content-Length header field with multiple
>> identical values, Part 1 Section 3.3.2 of HTTPbis says:
>>
>>> the recipient MUST either reject the message as invalid or
>>> replace the duplicated field-values with a single valid
>>> Content-Length field containing that decimal value prior to
>>> determining the message body length.
>>
>> It is not clear whether "recipient MUST replace" (a requirement on the
>> recipient) also implies that "a sender MUST replace [...] when
>> forwarding the message" (a requirement on the sender). This issue has
>> been raised on 2011/11/28, but the discussion diverged, and I could not
>> tell whether there was a consensus on what the correct interpretation is.
>>
>> Please decide whether a proxy MUST "fix" such Content-Length headers
>> when forwarding the message and adjust the above text to clarify one way
>> or another.
> 
> That's what the discussion converged to. I even modified haproxy in order
> to do so. The idea is simple : if you receive a message with multiple
> content lengths, either you can't deal with them and must reject the
> message, or you can deal with them and then you know how to fix the
> message before interpreting it or forwarding it, so you must do so.
> 
> Do you think the text needs to be adjusted ?

Yes, of course. The current text is not clear IMO, as I tried to explain
in the beginning of this message.


Cheers,

Alex.