[IPP] Oauth for IPP System Service

[IPP] Oauth for IPP System Service

Michael Sweet msweet at msweet.org
Fri Oct 9 20:40:32 UTC 2020


Piotr,

> On Oct 9, 2020, at 12:48 PM, Piotr Pawliczek <pawliczek at chromium.org> wrote:
> 
> Hi Smith,
> 
> Thank you very much for your help!
> BTW, have you considered using an HTTP response header (see https://tools.ietf.org/html/rfc6750#section-3) to communicate "server-uri" and "scope" to the client?

"server-uri" is not a registered parameter for the Bearer authentication scheme.

> In this case, we would not have to expose Get-System-Attributes and Get-Printer-Attributes to everyone.

These are already exposed to everything - the OAuth server isn't the only bit of information needed.

> 
> Best regards,
> Piotr 
> 
> On Wed, Oct 7, 2020 at 2:14 PM Kennedy, Smith (Wireless & IPP Standards) <smith.kennedy at hp.com> wrote:
> Hi Piotr,
> 
> I filed two errata against 5100.22: one to have Get-System-Attributes authentication semantics clarified, and another to have "oauth-authorization-server-uri" and "oauth-authorization-scope" attributes added as System Description attributes. The expectation is that a System object MUST NOT challenge a Client for authentication. Given that, if a System object supported OAuth, it ought to provide the "oauth-authorization-server-uri" and "oauth-authorization-scope" attributes as System Description attributes.
> 
> Smith
> 
> /**
>     Smith Kennedy
>     HP Inc.
> */
> 
>> On Oct 7, 2020, at 2:56 PM, Piotr Pawliczek <pawliczek at chromium.org> wrote:
>> 
>> Hi Smith,
>> 
>> Yes! Thank you very much. This is the problem I run into.
>> I just forgot to check Get-System-Attributes, so I didn't mention it.
>> 
>> Piotr
>> 
>> 
>> On Wed, Oct 7, 2020 at 1:51 PM Kennedy, Smith (Wireless & IPP Standards) <smith.kennedy at hp.com> wrote:
>> Hi there,
>> 
>> In "IPP Authentication Methods v1.0" on page 19 (https://ftp.pwg.org/pub/pwg/informational/bp-ippauth10-20190816-5199.10.pdf#page=19), edge 13 says 'Check for "oauth-authorization-server-uri" and "oauth-authorization-scope" Printer Description attributes'. If the IPP System supported OAuth, then presumably a Client could do a Get-System-Attributes operation to get these same two attributes. 
>> 
>> But if the System is allowed to respond with an authentication challenge (similar to Get-User-Printer-Attributes but not similar to Get-Printer-Attributes) then we have a problem because those two OAuth attributes can't be acquired by the Client. I cannot tell from the definition of "Get-System-Attributes" in IPP System v1.0 (http://ftp.pwg.org/pub/pwg/candidates/cs-ippsystem10-20191122-5100.22.pdf#page=70) whether a System object is allowed to challenge a Client for authentication in response to a Get-System-Attributes operation request.
>> 
>> Piotr, did I capture your "chicken-and-egg" concerns here?
>> 
>> Smith
>> 
>> /**
>>     Smith Kennedy
>>     HP Inc.
>> */
>> 
>>> On Oct 7, 2020, at 2:16 PM, Michael Sweet via ipp <ipp at pwg.org> wrote:
>>> 
>>> Piotr,
>>> 
>>> > On Oct 7, 2020, at 4:08 PM, Piotr Pawliczek via ipp <ipp at pwg.org> wrote:
>>> > 
>>> > Hi,
>>> > 
>>> > I am trying to figure out how to implement oauth authentication for the IPP System (e.g.: needed to send the Get-Printers request). I cannot find any references to oauth authorization in the document "IPP System Service v1.0 (SYSTEM)". Is there any plan to describe oauth authentication on the level of IPP System?
>>> 
>>> OAuth happens at the HTTP level, so the IPP Authentication Methods v1.0 document applies to all IPP services, not just printing.
>>> 
>>> ________________________
>>> Michael Sweet
>>> 
>>> 
>>> 
>>> _______________________________________________
>>> ipp mailing list
>>> ipp at pwg.org
>>> https://www.pwg.org/mailman/listinfo/ipp
>> 
> 

________________________
Michael Sweet





More information about the ipp mailing list