Re: [kitten] Use of GSS_Get_name_attribute() to obtain further attributes

Nico Williams <nico@cryptonector.com> Wed, 15 April 2015 19:59 UTC

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Date: Wed, 15 Apr 2015 14:59:29 -0500
From: Nico Williams <nico@cryptonector.com>
To: Benjamin Kaduk <kaduk@mit.edu>
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References: <552B7D5F.3000006@um.es> <1428933722.810.52.camel@willson.usersys.redhat.com> <alpine.GSO.1.10.1504131120270.22210@multics.mit.edu>
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Cc: kitten@ietf.org, Simo Sorce <simo@redhat.com>
Subject: Re: [kitten] Use of GSS_Get_name_attribute() to obtain further attributes
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On Mon, Apr 13, 2015 at 11:43:59AM -0400, Benjamin Kaduk wrote:
> I do not think I am opposed to (1) (i.e., letting GSS_Get_name_attribute()
> block on network interaction), but if we proceed down that route, I think
> we should file an erratum against 6880 to that effect.

I do not think that RFC6680 says or implies that only those attributes
listed by GSS_Inquire_name() may be gotten with
GSS_Get_name_attribute(), so to start with, we don't need to change
anything about RFC6680 w.r.t. that.

As for what blocking/non-blocking behavior can be expected, I'd say:

a) GSS_Inquire_name() can never "block",
b) GSS_Get_name_attribute() can, and whether it can should depend on the
   attribute being gotten, and preferably this is described by the
   attribute's documentation.

For the latter, see draft-williams-kitten-generic-naming-attributes-02,
which describes a generic attribute prefix by which the application can
request non-blocking behavior (which can fail if whatever data is not
available).

Nico
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