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    <p>+1<br>
    </p>
    <br>
    <div class="moz-cite-prefix">On 3/16/2017 7:58 AM, Axel Nennker via
      Openid-specs-ab wrote:<br>
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        <p class="MsoNormal"
          style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span
            style="font-size:12.0pt;font-family:"Times New
            Roman","serif"">Hi,<o:p></o:p></span></p>
        <p class="MsoNormal"
          style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span
            style="font-size:12.0pt;font-family:"Times New
            Roman","serif"">Nonce in the logout JWT is
            prohibited
          </span>to make a Logout Token syntactically invalid compared
          to an id_token.<o:p></o:p></p>
        <p class="MsoNormal"
          style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Wouldn’t
          it be more secure to use another signing key than the id_token
          signing key?<o:p></o:p></p>
        <p class="MsoNormal"
          style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Prohibiting
          nonce is a hack.<o:p></o:p></p>
        <p class="MsoNormal"
          style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Kind
          regards<o:p></o:p></p>
        <p class="MsoNormal"
          style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto">Axel<span
            style="font-size:12.0pt;font-family:"Times New
            Roman","serif""><o:p></o:p></span></p>
        <p class="MsoNormal"
          style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span
            style="font-size:12.0pt;font-family:"Times New
            Roman","serif""><o:p> </o:p></span></p>
        <p class="MsoNormal"
          style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span
            style="font-size:12.0pt;font-family:"Times New
            Roman","serif"">The following Claim MUST NOT
            be used within the Logout Token:
            <o:p></o:p></span></p>
        <p class="MsoNormal"><span
            style="font-size:12.0pt;font-family:"Times New
            Roman","serif"">nonce<o:p></o:p></span></p>
        <p class="MsoNormal" style="margin-left:72.0pt"><span
            style="font-size:12.0pt;font-family:"Times New
            Roman","serif"">PROHIBITED. A
          </span><span style="font-size:10.0pt;font-family:"Courier
            New"">nonce</span><span
            style="font-size:12.0pt;font-family:"Times New
            Roman","serif""> Claim MUST NOT be present.
            Its use is prohibited to make a Logout Token syntactically
            invalid if used in a forged Authentication Response in place
            of an ID Token. <o:p></o:p></span></p>
        <p class="MsoNormal"
          style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span
            style="font-size:12.0pt;font-family:"Times New
            Roman","serif"">Logout Tokens MAY contain
            other Claims. Any Claims used that are not understood MUST
            be ignored.
            <o:p></o:p></span></p>
        <p class="MsoNormal"
          style="mso-margin-top-alt:auto;mso-margin-bottom-alt:auto"><span
            style="font-size:12.0pt;font-family:"Times New
            Roman","serif"">A Logout Token MUST be signed
            and MAY also be encrypted. The same keys are used to sign
            and encrypt Logout Tokens as are used for ID Tokens. NOTE:
            The Logout Token is compatible with <a
              moz-do-not-send="true"
href="http://openid.net/specs/openid-connect-backchannel-1_0.html#I-D.ietf-secevent-token">Security
              Event Token (SET)</a> [I‑D.ietf‑secevent‑token] draft -00.
            <o:p></o:p></span></p>
        <p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
        <p class="MsoNormal"><span style="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"">
                Nennker, Axel
                <br>
                <b>Sent:</b> Thursday, March 16, 2017 12:49 PM<br>
                <b>To:</b> Mike Jones (<a class="moz-txt-link-abbreviated" href="mailto:Michael.Jones@microsoft.com">Michael.Jones@microsoft.com</a>);
                John Bradley (<a class="moz-txt-link-abbreviated" href="mailto:ve7jtb@ve7jtb.com">ve7jtb@ve7jtb.com</a>)<br>
                <b>Cc:</b> <a class="moz-txt-link-abbreviated" href="mailto:openid-specs-ab@lists.openid.net">openid-specs-ab@lists.openid.net</a><br>
                <b>Subject:</b> backchannel logout: events<o:p></o:p></span></p>
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        <p class="MsoNormal"><o:p> </o:p></p>
        <p class="MsoNormal">Hi,<o:p></o:p></p>
        <p class="MsoNormal"><o:p> </o:p></p>
        <p class="MsoNormal">Regarding
          <a class="moz-txt-link-freetext" href="https://openid.net/specs/openid-connect-backchannel-1_0.html">https://openid.net/specs/openid-connect-backchannel-1_0.html</a><o:p></o:p></p>
        <p class="MsoNormal"><o:p> </o:p></p>
        <p class="MsoNormal">I am wondering what the reason behind
          events is:<o:p></o:p></p>
        <p class="MsoNormal"><span
            style="font-size:12.0pt;font-family:"Times New
            Roman","serif"">events<o:p></o:p></span></p>
        <p class="MsoNormal" style="margin-left:36.0pt"><span
            style="font-size:12.0pt;font-family:"Times New
            Roman","serif"">REQUIRED. Claim whose value
            is a JSON object containing the member name
          </span><span style="font-size:10.0pt;font-family:"Courier
            New""><a class="moz-txt-link-freetext" href="http://schemas.openid.net/event/backchannel-logout">http://schemas.openid.net/event/backchannel-logout</a></span><span
            style="font-size:12.0pt;font-family:"Times New
            Roman","serif"">. This declares that the JWT
            is a Logout Token. The corresponding member value MUST be a
            JSON object and SHOULD be the empty JSON object </span><span
            style="font-size:10.0pt;font-family:"Courier New"">{}</span><span
            style="font-size:12.0pt;font-family:"Times New
            Roman","serif"">.
            <o:p></o:p></span></p>
        <p class="MsoNormal"><o:p> </o:p></p>
        <p class="MsoNormal" style="text-autospace:none">The reason, I
          think, to have “events” is to make the logout JWT compatible
          to SET:
          <a class="moz-txt-link-freetext" href="https://tools.ietf.org/html/draft-ietf-secevent-token-01">https://tools.ietf.org/html/draft-ietf-secevent-token-01</a><o:p></o:p></p>
        <p class="MsoNormal" style="text-autospace:none">But SET states:
          “Security Events are not commands issued between parties”<o:p></o:p></p>
        <p class="MsoNormal" style="text-autospace:none">While
          openid-connect-backchannel-1_0.html JWT is a command.<o:p></o:p></p>
        <p class="MsoNormal" style="text-autospace:none"><o:p> </o:p></p>
        <p class="MsoNormal" style="text-autospace:none">If we want SET
          compatibility wouldn’t it make more sense to have a SET
          compatible response to the logout command?<o:p></o:p></p>
        <p class="MsoNormal" style="text-autospace:none"><o:p> </o:p></p>
        <p class="MsoNormal" style="text-autospace:none">Why is SET
          compatibility important? Is it important enough to justify
          this really strange type specifier?<o:p></o:p></p>
        <pre>"events": {<o:p></o:p></pre>
        <pre>     <a class="moz-txt-link-rfc2396E" href="http://schemas.openid.net/event/backchannel-logout">"http://schemas.openid.net/event/backchannel-logout"</a>: {}<o:p></o:p></pre>
        <pre>     }<o:p></o:p></pre>
        <p class="MsoNormal" style="text-autospace:none"><o:p> </o:p></p>
        <p class="MsoNormal" style="text-autospace:none">Kind regards<o:p></o:p></p>
        <p class="MsoNormal" style="text-autospace:none">Axel<o:p></o:p></p>
        <p class="MsoNormal" style="text-autospace:none"><o:p> </o:p></p>
        <p class="MsoNormal" style="text-autospace:none"><o:p> </o:p></p>
        <p class="MsoNormal" style="text-autospace:none"><o:p> </o:p></p>
        <p class="MsoNormal" style="text-autospace:none"><span
style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#999999"><o:p> </o:p></span></p>
        <p class="MsoNormal" style="text-autospace:none"><span
style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#999999"><o:p> </o:p></span></p>
        <p class="MsoNormal" style="text-autospace:none"><span
style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#999999"><o:p> </o:p></span></p>
        <p class="MsoNormal" style="text-autospace:none"><span
style="font-size:10.0pt;font-family:"Arial","sans-serif";color:#999999"><o:p> </o:p></span></p>
        <p class="MsoNormal" style="text-autospace:none"><b><span
style="font-size:8.0pt;font-family:"Arial","sans-serif";text-transform:uppercase"
              lang="DE">Deutsche Telekom AG<o:p></o:p></span></b></p>
        <p class="MsoNormal" style="text-autospace:none"><span
style="font-size:8.0pt;font-family:"Arial","sans-serif""
            lang="DE">T-Labs (Research & Innovation)<br>
            Dipl.-Inform. Axel Nennker<br>
            Winterfeldtstr. 21, 10781 Berlin<br>
          </span><span
style="font-size:8.0pt;font-family:"Arial","sans-serif""
            lang="FR">+491702275312 (Mobile)<o:p></o:p></span></p>
        <p class="MsoNormal"><span
style="font-size:8.0pt;font-family:"Arial","sans-serif""
            lang="FR">E-Mail: <a class="moz-txt-link-abbreviated" href="mailto:axel.nennker@telekom.de">axel.nennker@telekom.de</a></span><span
            lang="DE"><o:p></o:p></span></p>
        <p class="MsoNormal"><span lang="DE"><o:p> </o:p></span></p>
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      <pre wrap="">_______________________________________________
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