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<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>One can build various control layers on top of RP affiliations
(a la SAML), with private local name bindings (a la SDSI).<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>For example:<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>Let the #fragment attached to the pseudonym URL be a URl-encoded,
base64-encoded public key. An AC can now sign its access requests to the SP,
expecting the SP to have the verification key for the signature block. The pseudonym
URL indicated in OAUTH consumer key identifies the public key to use (of many
that the affiliation group may hold for a given user, per SP transaction set).<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>One could let the PAPE value that any Sp must cite to obtain the
common pseudonym (plus public key fragment) be a signed(string), where string =
concat(AC realm, SP realm).that is, the ability to claim access to the pseudonym
is gated on the SP having from the AC a capability (the signed namespace->namespace
mapping) that tells the OP that the SP is a member of the AC’s (consumer) trust
network. The OP can have privileged access to the public key of the AC stored
in an AX record, treating the AC as an openid subscriber in its own right
(thanks Pat, for the idea!)<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>One can also play with shamir key splitting , so n of m
components must be applied (by an SP and an OP) before the AC will be able to
confirm the user has authorized the release of a particular photo set (executed
a particular SPARQL query…).Even more fun: play with RSA in similar vein.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";
color:windowtext'>From:</span></b><span style='font-size:10.0pt;font-family:
"Tahoma","sans-serif";color:windowtext'> general-bounces@openid.net
[mailto:general-bounces@openid.net] <b>On Behalf Of </b>Peter Williams<br>
<b>Sent:</b> Monday, January 12, 2009 11:21 PM<br>
<b>To:</b> Eddy Nigg (StartCom Ltd.)<br>
<b>Cc:</b> general@openid.net<br>
<b>Subject:</b> Re: [OpenID] Flickr / Yahoo OpenID implementation<o:p></o:p></span></p>
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<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>And is it true that if the user delegates to an OP identifier
(only) inducing directed id flow, that the user will be logged in to the RP as
the finalized openid (rather than the user supplied id), even though the OP
made an assertion about a Yahoo pseudonym?<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>If an RP now send a unique PAPE value that controls the value of
the pseudonym, and an OP uses the same pseudonym for any RP citing that same
PAPE request value, each RP with knowledge of the pape seed value will (a) have
a common key for the user per pape value (the pseudonym),(b) a per RP
persistent mapping between the finalized URL -> pseudonym.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>In an OAUTH environment, a user can now release to the AC
knowledge of the finalized URL that the SP has bound to the very same pseudonym
to which the AC has bound its own finalized URL. They can now engage in peer
entity authentication without the OP. Release of the local name binding at the
SP to the AC is a user act of approval to pull the users data, using the
pseudonym as the consumer key and the SP-local finalizedURL as the consumer
secret.<o:p></o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'><o:p> </o:p></span></p>
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<p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif";
color:windowtext'>From:</span></b><span style='font-size:10.0pt;font-family:
"Tahoma","sans-serif";color:windowtext'> general-bounces@openid.net
[mailto:general-bounces@openid.net] <b>On Behalf Of </b>Eddy Nigg (StartCom
Ltd.)<br>
<b>Sent:</b> Monday, January 12, 2009 11:07 PM<br>
<b>To:</b> Eran Hammer-Lahav<br>
<b>Cc:</b> general@openid.net<br>
<b>Subject:</b> Re: [OpenID] Flickr / Yahoo OpenID implementation<o:p></o:p></span></p>
</div>
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<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><br>
On 01/13/2009 08:40 AM, Eran Hammer-Lahav: <o:p></o:p></p>
<p class=MsoNormal><o:p> </o:p></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'>OpenID is a little/vary/completely broken when it comes to its
handling of Claimed Identifiers. The level of how broken depends on your use
case and threat model. It is also inconsistent in that if you use your blog URL
(custom domain name) as an OpenID, but the hosting service you use redirects to
another domain (for example, you use <a href="http://example.com">http://example.com</a>
as your blog, but your service is serving it off <a
href="http://example.blogservice.com">http://example.blogservice.com</a> or <a
href="http://blogservice.com/example">http://blogservice.com/example</a>), the
RP has to use the redirected URL and not the one you entered.</span><o:p></o:p></p>
<p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";
color:#1F497D'> </span><o:p></o:p></p>
<p class=MsoNormal style='margin-bottom:12.0pt'>Correct! And this is by design,
it's not broken. And don't even think about changing this pattern :-)<o:p></o:p></p>
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<p class=MsoNormal>Regards <o:p></o:p></p>
</td>
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<tr>
<td colspan=2 style='padding:0in 0in 0in 0in'>
<p class=MsoNormal> <o:p></o:p></p>
</td>
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<p class=MsoNormal>Signer: <o:p></o:p></p>
</td>
<td style='padding:0in 0in 0in 0in'>
<p class=MsoNormal>Eddy Nigg, <a href="http://www.startcom.org">StartCom Ltd.</a><o:p></o:p></p>
</td>
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<td style='padding:0in 0in 0in 0in'>
<p class=MsoNormal>Jabber: <o:p></o:p></p>
</td>
<td style='padding:0in 0in 0in 0in'>
<p class=MsoNormal><a href="xmpp:startcom@startcom.org">startcom@startcom.org</a><o:p></o:p></p>
</td>
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<td style='padding:0in 0in 0in 0in'>
<p class=MsoNormal>Blog: <o:p></o:p></p>
</td>
<td style='padding:0in 0in 0in 0in'>
<p class=MsoNormal><a href="http://blog.startcom.org">Join the Revolution!</a><o:p></o:p></p>
</td>
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<td style='padding:0in 0in 0in 0in'>
<p class=MsoNormal>Phone: <o:p></o:p></p>
</td>
<td style='padding:0in 0in 0in 0in'>
<p class=MsoNormal>+1.213.341.0390<o:p></o:p></p>
</td>
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<td colspan=2 style='padding:0in 0in 0in 0in'>
<p class=MsoNormal> <o:p></o:p></p>
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<p class=MsoNormal><o:p> </o:p></p>
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