Re: [http-state] Is this an omission in the parser rules of draft-ietf-httpstate-cookie-21?

Peter Saint-Andre <stpeter@stpeter.im> Fri, 11 February 2011 00:59 UTC

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Date: Thu, 10 Feb 2011 17:59:21 -0700
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Cc: http-state@ietf.org
Subject: Re: [http-state] Is this an omission in the parser rules of draft-ietf-httpstate-cookie-21?
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On 2/4/11 12:29 PM, Adam Barth wrote:
> On Fri, Feb 4, 2011 at 11:24 AM, Roy T. Fielding <fielding@gbiv.com>; wrote:
>> On Feb 4, 2011, at 10:51 AM, Adam Barth wrote:
>>> On Fri, Feb 4, 2011 at 10:47 AM, Remy Lebeau <remy@lebeausoftware.org>; wrote:
>>>> -------- Original Message --------
>>>> Subject: Re: [http-state] Is this an omission in the parser rules of
>>>> draft-ietf-httpstate-cookie-21?
>>>> From: Adam Barth
>>>> Date: Fri, February 04, 2011 10:19 am
>>>> To: Remy Lebeau
>>>> Cc: http-state@ietf.org
>>>>
>>>>> The draft gives user agents precise
>>>>> instructions for how to parse all
>>>>> manner of cookies, including cookies with
>>>>> values that contain quote characters. That
>>>>> information is contained in Section 5
>>>>
>>>> I have re-read Section 5 and I do not see its grammar or parsing rules
>>>> accounting for quoted-string values at all. It only says to remove WSP
>>>> characters surrounding extracted names and values, and quote characters
>>>> are not part of the WSP definition. So what am I missing? Where exactly
>>>> does it say how to unquote a quoted-string used in attribute values?
>>>
>>> Precisely.  It does not say to unquote a quoted-string because that's
>>> not how cookies work.  The role of the quote character is cookies is
>>> identical to the role of the "!" character.  That is, neither play a
>>> special role in the protocol.  Any representations by the contrary by
>>> 2109 or any other document are fiction and have only caused pain and
>>> misery in the world.
>>
>> That may be, but the grammar for server generation of set-cookie
>> values is clearly wrong because use of DQUOTE in cookie values is
>> common (roughly 10% of the values in my browser cookie store) and
>> previously defined, even if we consider DQUOTE to be part of the
>> value string.  Let's just change the generating grammar for value to
>> match how cookies are actually parsed and only exclude characters
>> that are known to cause failures.
> 
> The grammar is not used for parsing.  Parsing is defined in Section 5,
> not Section 4.

Right. And I think the revised text in version -21 (with revisions to
address the IESG comment from Robert Sparks) makes that fairly clear.

Adam, did you propose specific text addressing Dan Winship's original
issue about "cookie-value=token"? As far as I can see, that's the only
substantive issue raised in this thread, but I admit that I might have
missed something.

Peter

-- 
Peter Saint-Andre
https://stpeter.im/