RE: #78: Relationship between 401, Authorization and WWW-Authenticate

 On Tue, 26 Jul 2011 10:13:11 +1000, Manger, James H wrote:
>>On Mon, Jul 25, 2011 at 11:54:07PM +0200, Julian Reschke wrote:
>>> Maybe...:
>>>
>>> Use of the Authorization header to transfer credentials implies
>>> "Cache-Control: private" [ref] and thus affects cacheability of
>>> responses. Thus, definitions of new authentication schemes that do 
>>> not
>>> use "Authorization" will need to ensure that response messages do 
>>> not
>>> leak in an unintended way, for instance by specifying 
>>> "Cache-Control" or
>>> "Vary: *" [ref] explicitly.
>>>
>>> Feedback appreciated,
>
>>I can read the first sentence in two ways :
>>  - if a server or intermediary receives an Authorization header, it 
>> must
>>    assume that "Cache-Control: private" is implied
>>  - if a client wants to emit an Authorization header, it must also 
>> add
>>    a "Cache-Control: private" header
>>
>>I think the former was meant given the second sentence, though I'm 
>> not
>>100% certain. If so, maybe we should focus on the recipient of the 
>> message
>>and replace "Use of" with "Presence of" (or anything equivalent).
>>
>>The second part is clear enough however.
>
>
> The first sentence should be read a 3rd way:
>   - if an Authorization header is present in a request, the 
> corresponding
>     response MUST be treated as though it includes "Cache-Control: 
> private",
>     unless it explicitly includes a Cache-Control header

 That wording in turn implies "Cache-Control: something-new" reverts the 
 object to public access. Not a good idea IMHO to premise it on the 
 existing of the header field.
  "unless it explicitly includes Cache-Control: public" would be better 
 wording.

 AYJ

>
> draft-ietf-httpbis-p7-auth-15#section-4.1 already contains 20 lines
> of text (1 paragraph plus 3 dot points) about caching when a request
> includes an Authorization header. This shouldn't be paraphrased
> immediately after that text with the first sentence above "... 
> implies
> Cache-Control: private...". I am not sure that the 20 lines are
> totally consistent with this first sentence.
>
> Perhaps the existing 20 lines were going to be removed, to be
> replaced with a single sentence about implying "Cache-Control:
> private" by default? That sounds ok to me, as long as the first
> sentence makes it clear that "Cache-Control: private" is implied for
> the corresponding response.
>
> Alternatively, if the existing 20 lines are kept, then just add the
> 2nd sentence of the Julian's text as a new paragraph at the end of
> section 4.1 [draft-ietf-httpbis-p7-auth-15#section-4.1]:
>
>   Use of authentication schemes that do not
>   use "Authorization" will need to ensure that response messages do 
> not
>   leak in an unintended way, for instance by specifying 
> "Cache-Control" or
>   "Vary: *" [ref] explicitly.
>
> --
> James Manger

Received on Tuesday, 26 July 2011 01:36:23 UTC