<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">I agree that RP delegation should be possible and even desirable.<div><br></div><div>To do that safely the OP needs to do RP discovery over SSL or discover a XRD with detached sig for the RP.</div><div><br></div><div>Otherwise you open up Man in the Middle attacks. </div><div><br></div><div>My point was that in the existing spec to prevent interception of tokens and attributes, the Realm that is displayed by the OP to the user needs to match where the assertion is sent.</div><div><br></div><div>I agree that this is something that should be addressed in openID 2.1 ether for XRD with dsig or via XRDS with TLS.</div><div><br></div><div>John B.</div><div><br><div><div>On 14-May-09, at 12:24 AM, Dirk Balfanz wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">I don't see why a realm shouldn't be able to delegate to a return_to URL the same way that a user id can delegate to an OP endpoint. This includes delegating from http to https, or even to a different domain altogether. Over on the XRI TC we've been talking about how to do this securely, e.g., by signing the XRD that does the delegation: <a href="http://wiki.oasis-open.org/xri/XrdOne/XmlDsigProfile">http://wiki.oasis-open.org/xri/XrdOne/XmlDsigProfile</a><br> <br>Dirk.<br><br>On Wed, May 13, 2009 at 7:43 PM, John Bradley <<a href="mailto:jbradley@mac.com">jbradley@mac.com</a>> wrote:<br>> Luke,<br>> Realm was called trust_root in 1.1, and is a bit like audience restriction<br> > in SAML. <br>> It is the display version of the return_to, and also used for RP discovery<br>> by the OP.<br>> I am not certain what the problem is with it being https: if the return_to<br>> is https:.<br> > There is explicitly no connection to be inferred by DNS authority between<br>> URI differing in scheme. <br>> Differentiating TLS by its own scheme is a decision we have to live with.<br>> The user should consent to authentication for the site they are logging<br> > into. <br>> <a href="http://open.lukesheppard.com">http://open.lukesheppard.com</a> and <a href="https://open.lukesheppard.com">https://open.lukesheppard.com</a> could<br>> be different sites.<br>> If the RP has both HTTP and HTTPS the best practice would be to always use<br> > the https: version for realm so that RP discovery cant be spoofed via DNS.<br>> Regards<br>> John B.<br>> On 13-May-09, at 2:10 AM, <a href="mailto:specs-request@openid.net">specs-request@openid.net</a> wrote:<br> ><br>> Date: Tue, 12 May 2009 23:10:38 -0700<br>> From: Luke Shepard <<a href="mailto:lshepard@facebook.com">lshepard@facebook.com</a>><br>> Subject: Should we recommend that return_to url is always HTTPS? What<br> > about realm?<br>> To: OpenID Specs Mailing List <<a href="mailto:specs@openid.net">specs@openid.net</a>><br>> Message-ID: <<a href="mailto:C62FB26E.BCE7%25lshepard@facebook.com">C62FB26E.BCE7%lshepard@facebook.com</a>><br> > Content-Type: multipart/related;<br>> boundary="_004_C62FB26EBCE7lshepardfacebookcom_";<br>> type="multipart/alternative"<br>><br>> --_004_C62FB26EBCE7lshepardfacebookcom_<br>> Content-Type: multipart/alternative;<br> > boundary="_000_C62FB26EBCE7lshepardfacebookcom_"<br>><br>> --_000_C62FB26EBCE7lshepardfacebookcom_<br>> Content-Type: text/plain; charset="iso-8859-1"<br>> Content-Transfer-Encoding: quoted-printable<br> ><br>> In testing my relying party, it seems clear that the return_to url SHOULD a=<br>> lways be HTTPS. Therefore, then, the realm will always need to be HTTPS as =<br>> well.<br>><br>> If the return_to is HTTP, then if the response comes in the form of a POST =<br> > from a provider that supports SSL, then the user will see a browser warning=<br>> for posting to an insecure form.<br>><br>> Here's an example:<br>><br>> - realm: <a href="http://open.lukeshepard.com/">http://open.lukeshepard.com/</a><br> > - return_to: <a href="http://open.lukeshepard.com/openid/receiver.php">http://open.lukeshepard.com/openid/receiver.php</a><br>> - provider endpoint: <a href="https://www.google.com/accounts/o8/ud">https://www.google.com/accounts/o8/ud</a><br> ><br>> Let's suppose that the response is too long for a GET redirect, so the prov=<br>> ider chooses to POST (as Google and others sometimes do).<br>><br>> The user would see a warning like this:<br>><br> > [<a href="cid:3325014638_6495490">cid:3325014638_6495490</a>]<br>><br>> To preserve the user experience and avoid that popup, relying parties would=<br>> want to make sure their receiver is HTTPS.<br>><br>> Alternative<br>><br>> What do you think about loosening the realm/return_to protocol/domain match=<br> > requirements?<br>><br>> This kinda sucks though, since it means the REALM also must be HTTPS, even =<br>> though the HTTP version would seem to be "canonical". I wonder, would we al=<br>> low an HTTPS return_to if the realm was HTTP? It seems that the HTTP versio=<br> > n of the realm would be better, and should be able to mean "accept either p=<br>> rotocol". Or better yet, you should be able to specify a realm without a pr=<br>> otocol at all.<br>><br>> Thoughts?<br> ><br>> _______________________________________________<br>> specs mailing list<br>> <a href="mailto:specs@openid.net">specs@openid.net</a><br>> <a href="http://openid.net/mailman/listinfo/specs">http://openid.net/mailman/listinfo/specs</a><br> ><br>><br><br></blockquote></div><br></div></body></html>