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<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D">Hi Salvatore,<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">Have you considered using the Keystone ‘role’ for this? For example, for this service you might have two roles, a ‘user’ and ‘admin’ role. When the Keystone
middleware validates the request, e.g. token, the service will be able to access the role and if it is ‘admin’ then additional attributes could then be included in the response.<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">Peter.<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"">From:</span></b><span style="font-size:10.0pt;font-family:"Tahoma","sans-serif""> Salvatore Orlando [mailto:sorlando@nicira.com]
<br>
<b>Sent:</b> Tuesday, April 30, 2013 3:57 PM<br>
<b>To:</b> OpenStack Development Mailing List<br>
<b>Subject:</b> [openstack-dev] A (probably) interesting authZ question<o:p></o:p></span></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Hi,<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">I am sending this to a broader audience since recently for a patch on openstack-network we've come across a peculiar authZ problem, which might have been already solved in some other project.<o:p></o:p></p>
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<p class="MsoNormal">Basically some API resources have composite attributes, ie: attributes whose value is a dict.<o:p></o:p></p>
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<p class="MsoNormal">In some case there might be a need to authorize access to such attributes.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">For instance, in this specific case we have:<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">"router" : {<o:p></o:p></p>
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<p class="MsoNormal"> <... some router stuff ..><o:p></o:p></p>
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<p class="MsoNormal"> "external_gateway_info" : {<o:p></o:p></p>
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<p class="MsoNormal"> "network_id": "some_uuid",<o:p></o:p></p>
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<p class="MsoNormal"> "enable_snat": "true"<o:p></o:p></p>
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<p class="MsoNormal"> }<o:p></o:p></p>
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<p class="MsoNormal"> < .. some more router stuff ... ><o:p></o:p></p>
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<p class="MsoNormal">}<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">and we would like to say that the policy for setting enable_snat must be rule:admin_only.<o:p></o:p></p>
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<p class="MsoNormal">there are several options, among which:<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">1) this way of doing authZ does not make sense at all. authZ should be enforced on resources not single attributes<o:p></o:p></p>
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<p class="MsoNormal">2) If the particular attribute comes from some specific extension, instead of policing access one should be allowed to turn administratively on/off the extension itself<o:p></o:p></p>
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<p class="MsoNormal">3) We should have a rule check for sub-attributes (like FieldCheck in quantum/policy.py).<o:p></o:p></p>
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<p class="MsoNormal">4) The enable_snat attribute should be moved to the first-level resource, and authZ checked as with any other attribute<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">any opinion on the subject would be greatly appreciated.<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
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<p class="MsoNormal">Regards,<o:p></o:p></p>
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<p class="MsoNormal">Salvatore<o:p></o:p></p>
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