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<p class="MsoNormal"><span style="font-size:11.0pt">Hello All!<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">We recently deployed a new version of our Proxy IdP that uses SAML as the authentication mechanism to Proxied IdPs within our organization.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">This uses the native features of IdPv4 and is a much cleaner solution than our SP-infront-of-an-IdP and External Auth pattern that we had before.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">One thing continues to be a mystery though, and that is how do we configure things that influence the SP side’s outbound AuthnRequest?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">With the previous incarnation, we would just edit shibboleth2.xml in the SP side as we’re all experts on that.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">However with this now being built into the IdP, such SP options and where to control them are not so obvious<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">So the genesis of this question is that one of our Proxied IdP partners noticed a change in the AuthnRequest from the new v4 Proxy IdP that unfortunately caused an outage for them.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">The attribute ‘ProtocolBinding’ is missing, and apparently their IdP needs this to function in order to select the proper ACS endpoint. Even though the proper SAML assertion<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Consumption endpoint is in the AuthnRequest, such was ignored by their IdP because the ProtocolBinding attribute wasn’t also there.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">To be fair, their IdP is not Shibboleth, it’s something custom with endpoints that end in aspx, and it’s probably not quite right – ignoring things in the AuthnRequest, but there isn’t anything we can do about
that. <o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">We confirmed that this attribute was present in the previous incarnation, and now we have a request from that IdP operator to have it be sent with the new IdPv4 AuthnRequest.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Is there a way we can do this and make the new outbound AuthnRequest behave the same as it did before by including the ProtocolBinding attribute?
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Or, is there some other solid argument we can make for not doing this and replying to that IdP operator that their software is not following the standard?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Thanks!<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">-- <o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">Jeremy Scott<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">Identity and Access Management<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">Application Integration Services
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">Division of Information Technology<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt">University of Wisconsin-Madison<o:p></o:p></span></p>
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<p class="MsoNormal"><span style="font-size:11.0pt">jeremy.scott@wisc.edu</span><span style="font-size:11.0pt"><o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt"><o:p> </o:p></span></p>
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