Re: [OAUTH-WG] Native clients & 'confidentiality'

Michael Thomas <> Mon, 19 December 2011 18:00 UTC

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Date: Mon, 19 Dec 2011 10:00:04 -0800
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Subject: Re: [OAUTH-WG] Native clients & 'confidentiality'
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On 12/19/2011 09:50 AM, Paul Madsen wrote:
> Hi Mike, to some extent I think my question is not about specific 
> security characteristics, but rather whether its realistic for our 
> group to mandate that both server & native clients have the *same* 
> security characteristics - particularly the ability to 'securely' 
> authenticate to the AS on the token endpoint.

Well given the explanation Justin just gave, they do not. As I understand
your initial query, redefining a native/embedded app as "confidential" 
alter that reality. But my first question about requirements still is 
what are you trying to protect from whom, and what is the level of risk that
your profile of oauth is willing to tolerate?


> thanks
> paul
> On 12/19/11 12:18 PM, Michael Thomas wrote:
>> On 12/19/2011 04:19 AM, Paul Madsen wrote:
>>> Hi, the Online Media Authorization Protocol (OMAP) is a (as yet 
>>> unreleased) profile of OAuth 2.0 for online delivery of video 
>>> content based on a user's subscriptions (the TV Everywhere use case)
>>> We want to support both server & native mobile clients. It is for 
>>> the second class of clients that I'd appreciate some clarification 
>>> of 'confidentiality' as defined in OAuth 2.
>>> OAuth 2 distinguishes confidential & public clients based on their 
>>> ability to secure the credentials they'd use to authenticate to an 
>>> AS - confidential clients can protect those credentials, public 
>>> clients can't.
>>> Notwithstanding the above definition, the spec gives a degree of 
>>> discretion to the AS
>>>     The client type designation is based on the authorization server's
>>>     definition of secure authentication and its acceptable exposure
>>>     levels of client credentials.
>>> Give this discretion, is it practical for the OMAP spec to stipulate 
>>> that 'All Clients (both server & native mobile), MUST be 
>>> confidential', ie let each individual OMAP AS specify its own 
>>> requirements of clients and their ability to securely authenticate?
>> Hi,
>> Can you say exactly what your security requirements are before trying 
>> to determine which
>> (if either) is the right answer? I've got some concerns in this area 
>> that I'm trying to understand
>> and am not sure if they're related to your concern or not. Part of 
>> this is that I really don't
>> understand what the difference is between a "public" client and a 
>> "confidential client" and
>> rereading the draft isn't helping me. In particular, can a iPhone app 
>> with a UIWebView *ever*
>> be a "confidential" client, and if so how?
>> Mike