<?xml version="1.0"encoding="utf-8"?> <!-- This template is for creating an Internet Draft using xml2rfc, which is available here: http://xml.resource.org. -->encoding="UTF-8"?> <!DOCTYPE rfcSYSTEM "rfc2629.dtd"[<!-- One method to get references from the online citation libraries. There has to be one entity for each item to be referenced. 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If only the current year is specified, xml2rfc will fill in the current day and month for you. If the year is not the current one, it is necessary to specify at least a month (xml2rfc assumes day="1" if not specified for the purpose of calculating the expiry date). With drafts it is normally sufficient to specify just the year. --> <!-- Meta-data Declarations -->year="2022" month="August"/> <area>Security</area><workgroup>ACE Working Group</workgroup> <!-- WG name at the upperleft corner of the doc, IETF is fine for individual submissions. If this element is not present, the default is "Network Working Group", which is used by the RFC Editor as a nod to the history of the IETF. --> <keyword>CoAP, OAuth 2.0, Access Control, Authorization, Internet<workgroup>ACE</workgroup> <keyword>CoAP</keyword> <keyword>OAuth 2.0</keyword> <keyword>Access Control</keyword> <keyword>Authorization</keyword> <keyword>Internet of Things</keyword><!-- Keywords will be incorporated into HTML output files in a meta tag but they have no effect on text or nroff output. If you submit your draft to the RFC Editor, the keywords will be used for the search engine. --><abstract> <t>This specification defines new parameters and encodings for the OAuth 2.0 token and introspection endpoints when used with the framework forauthenticationAuthentication andauthorizationAuthorization forconstrained environmentsConstrained Environments (ACE). These are used to express the proof-of-possession (PoP) key the client wishes to use, theproof-of-possessionPoP key that theAuthorization Serverauthorization server has selected, and the PoP key theResource Serverresource server uses to authenticate to the client.</t> </abstract> </front> <middle><!-- ***************************************************** --><section anchor="intro"title="Introduction">numbered="true" toc="default"> <name>Introduction</name> <t>The Authentication and Authorization for Constrained Environments (ACE) specification <xreftarget="I-D.ietf-ace-oauth-authz"/>target="RFC9200" format="default"/> requires some new parameters for interactions with the OAuth 2.0 <xreftarget="RFC6749"/>target="RFC6749" format="default"/> token and introspection endpoints, as well as some new claims to be used in access tokens. These parameters and claims can also be used in other contexts and have therefore been put into a dedicateddocument,document to facilitate their use in a manner independent of <xreftarget="I-D.ietf-ace-oauth-authz"/>.</t>target="RFC9200" format="default"/>.</t> <t>Note that although all examples are shown in Concise Binary Object Representation (CBOR) <xreftarget="RFC8949"/>,target="RFC8949" format="default"/>, JSON <xreftarget="RFC8259"/> MAYtarget="RFC8259" format="default"/> <bcp14>MAY</bcp14> be used as an alternative for HTTP-based communications, as specified in <xreftarget="I-D.ietf-ace-oauth-authz"/>.</t>target="RFC9200" format="default"/>.</t> </section><!-- ***************************************************** --><section anchor="terminology"title="Terminology">numbered="true" toc="default"> <name>Terminology</name> <t>The key words"MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY","<bcp14>MUST</bcp14>", "<bcp14>MUST NOT</bcp14>", "<bcp14>REQUIRED</bcp14>", "<bcp14>SHALL</bcp14>", "<bcp14>SHALL NOT</bcp14>", "<bcp14>SHOULD</bcp14>", "<bcp14>SHOULD NOT</bcp14>", "<bcp14>RECOMMENDED</bcp14>", "<bcp14>NOT RECOMMENDED</bcp14>", "<bcp14>MAY</bcp14>", and"OPTIONAL""<bcp14>OPTIONAL</bcp14>" in this document are to be interpreted as described inBCP 14BCP 14 <xreftarget="RFC2119"/>target="RFC2119" format="default"/> <xreftarget="RFC8174"/>target="RFC8174" format="default"/> when, and only when, they appear in all capitals, as shown here.</t> <t>Readers are assumed to be familiar with the terminology from <xreftarget="I-D.ietf-ace-oauth-authz"/>,target="RFC9200" format="default"/>, especially the terminology for entities in the architecture such as client (C), resource server(RS)(RS), and authorization server (AS).</t> <t>Terminology from <xreftarget="RFC8152"/>target="RFC8152" format="default"/> is used in the examples, especiallyCOSE_KeyCOSE_Key, which is defined insection 7 of<xreftarget="RFC8152"/>.</t>target="RFC8152" sectionFormat="of" section="7"/>.</t> <t>Note that the term "endpoint" is used here following its OAuth 2.0 <xreftarget="RFC6749"/>target="RFC6749" format="default"/> definition, which is to denote resources such as token and introspection at the AS and authz-info at the RS. The Constrained Application Protocol (CoAP) <xreftarget="RFC7252"/>target="RFC7252" format="default"/> definition, which is"An"[a]n entity participating in the CoAPprotocol"protocol", is not used in this specification.</t> </section><!-- ***************************************************** --><section anchor="tokenEndpoint"title="Parametersnumbered="true" toc="default"> <name>Parameters for the TokenEndpoint">Endpoint</name> <t>This section defines additional parameters for the interactions with the token endpoint in the ACE framework <xreftarget="I-D.ietf-ace-oauth-authz"/>.</t>target="RFC9200" format="default"/>.</t> <section anchor="tokenRequest"title="Client-to-AS Request">numbered="true" toc="default"> <name>Client-to-AS Request</name> <t>This section defines the"req_cnf"<tt>req_cnf</tt> parameter allowing clients to request a specificproof-of-possessionPoP key in an access token from a token endpoint in the ACE framework <xreftarget="I-D.ietf-ace-oauth-authz"/>: <list style="hanging"> <t hangText="req_cnf"><vspace blankLines="0"/> OPTIONAL.target="RFC9200" format="default"/>: </t> <dl newline="true" spacing="normal"> <dt>req_cnf</dt> <dd> <bcp14>OPTIONAL</bcp14>. This field contains information about the key the client would like to bind to the access token forproof-of-possession.proof of possession. It isRECOMMENDED<bcp14>RECOMMENDED</bcp14> that an AS rejects a request containing a symmetric key value in the'req_cnf'<tt>req_cnf</tt> field (kty=Symmetric), since the AS is expected to be able to generate better symmetric keys than a constrainedclientclient. (Note: this does not apply to key identifiers referencing a symmetrickey).key.) The ASMUST<bcp14>MUST</bcp14> verify that the client really is in possession of the corresponding key. Profiles of <xreftarget="I-D.ietf-ace-oauth-authz"/>target="RFC9200" format="default"/> using this specificationMUST<bcp14>MUST</bcp14> define theproof-of-possessionPoP method used by theAS,AS if they allow clients to use this request parameter. Values of this parameter follow the syntax and semantics of the"cnf"<tt>cnf</tt> claim either fromsection 3.1 of<xreftarget="RFC8747"/>target="RFC8747" sectionFormat="of" section="3.1"/> for CBOR-based interactions or fromsection 3.1 of<xreftarget="RFC7800"/>target="RFC7800" sectionFormat="of" section="3.1"/> for JSON-basedinteractions.</t> </list> </t>interactions.</dd> </dl> <t><xreftarget="fig:symmATreq"/>target="fig_symmATreq" format="default"/> shows a request for an access token using the"req_cnf"<tt>req_cnf</tt> parameter to request a specific public key asproof-of-possessiona PoP key. The content is displayed in CBOR diagnosticnotation, without abbreviations andnotation withline-breaksline breaks for betterreadability.readability.</t> <figurealign="center" anchor="fig:symmATreq" title="Example requestanchor="fig_symmATreq"> <name>Example Request for anaccess token boundAccess Token Bound to anasymmetric key."> <artwork align="left"><![CDATA[Asymmetric Key</name> <sourcecode name="" type="cbor-diag"><![CDATA[ Header: POST (Code=0.02) Uri-Host: "as.example.com" Uri-Path: "token" Content-Format:"application/ace+cbor"application/ace+cbor Payload: {"req_cnf"/ req_cnf / 4 : {"COSE_Key"/ COSE_Key / 1 : {"kty"/ kty / 1 :"EC2", "kid"2 /EC2/, / kid / 2 : h'11',"crv" : "P-256", "x"/ crv / -1 : 1 /P-256/, / x / -2 : h'BAC5B11CAD8F99F9C72B05CF4B9E26D24 4DC189F745228255A219A86D6A09EFF',"y"/ y / -3 : h'20138BF82DC1B6D562BE0FA54AB7804A3 A64B6D72CCFED6B6FB6ED28BBFC117E' } } }]]></artwork> </figure></t> </section><!-- C->AS -->]]></sourcecode> </figure> </section> <section anchor="tokenResponse"title="AS-to-Client Response">numbered="true" toc="default"> <name>AS-to-Client Response</name> <t>This section defines the following additional parameters for an AS response to a request to the token endpoint:<list style="hanging"> <t hangText="cnf"><vspace blankLines="0"/> REQUIRED</t> <dl newline="true" spacing="normal"> <dt>cnf</dt> <dd> <bcp14>REQUIRED</bcp14> if the token type is "pop" and a symmetric key is used.MAY<bcp14>MAY</bcp14> be present for asymmetricproof-of-possessionPoP keys. This field contains theproof-of-possessionPoP key that the AS selected for the token. Values of this parameter follow the syntax and semantics of the"cnf"<tt>cnf</tt> claim either fromsection 3.1 of<xreftarget="RFC8747"/>target="RFC8747" sectionFormat="of" section="3.1"/> for CBOR-based interactions or fromsection 3.1 of<xreftarget="RFC7800"/>target="RFC7800" sectionFormat="of" section="3.1"/> for JSON-based interactions. See <xreftarget="paramCnf"/>target="paramCnf" format="default"/> for additional discussion of the usage of this parameter.<vspace blankLines="1"/></t> <t hangText="rs_cnf"><vspace blankLines="0"/> OPTIONAL</dd> <dt>rs_cnf</dt> <dd> <bcp14>OPTIONAL</bcp14> if the token type is "pop" and asymmetric keys are used.MUST NOT<bcp14>MUST NOT</bcp14> be present otherwise. This field contains information about the public key used by the RS to authenticate. If this parameter is absent, either the RS does not use a public key or the AS knows that the RS can authenticate itself to the client without additional information. Values of this parameter follow the syntax and semantics of the"cnf"<tt>cnf</tt> claim either fromsection 3.1 of<xreftarget="RFC8747"/>target="RFC8747" sectionFormat="of" section="3.1"/> for CBOR-based interactions or fromsection 3.1 of<xreftarget="RFC7800"/>target="RFC7800" sectionFormat="of" section="3.1"/> for JSON-based interactions. See <xreftarget="paramCnf"/>target="paramCnf" format="default"/> for additional discussion of the usage of this parameter.</t> </list> </t></dd> </dl> <t><xreftarget="fig:symmATres"/>target="fig_symmATres" format="default"/> shows an AS response containing a token and a"cnf"<tt>cnf</tt> parameter with a symmetricproof-of-possession key.PoP key.</t> <figurealign="center" anchor="fig:symmATres" title="Exampleanchor="fig_symmATres"> <name>Example ASresponseResponse with anaccess token boundAccess Token Bound to asymmetric key."> <artwork align="left"><![CDATA[Symmetric Key</name> <sourcecode name="" type="cbor-diag"><![CDATA[ Header: Created (Code=2.01) Content-Format:"application/ace+cbor"application/ace+cbor Payload: {"access_token"/ access_token / 1 :h'4A5015DF686428 ...h'4A5015DF686428/... (remainder of CWT omitted for brevity; CWT contains COSE_Key in the "cnf"claim)', "cnf"claim)/', / cnf / 8 : {"COSE_Key"/ COSE_Key / 1 : {"kty" : "Symmetric", "kid"/ kty / 1 : 4 / Symmetric /, / kid / 2 : h'DFD1AA97',"k"/ k / -1 : h'849B5786457C1491BE3A76DCEA6C427108' } } }]]></artwork> </figure></t>]]></sourcecode> </figure> <t><xreftarget="fig:asymmATres"/>target="fig_asymmATres" format="default"/> shows an AS response containing a token bound to a previously requested asymmetricproof-of-possessionPoP key (not shown) anda "rs_cnf"an <tt>rs_cnf</tt> parameter containing the public key of theRS.RS.</t> <figurealign="center" anchor="fig:asymmATres" title="Exampleanchor="fig_asymmATres"> <name>Example ASresponse, includingResponse Including the RS'spublic key."> <artwork align="left"><![CDATA[Public Key</name> <sourcecode name="" type="cbor-diag"><![CDATA[ Header: Created (Code=2.01) Content-Format:"application/ace+cbor"application/ace+cbor Payload: {"access_token"/ access_token / 1 :h'D08343A1010AA1054D2A45DF6FBC5A5A ...h'D08343A1010AA1054D2A45DF6FBC5A5A/... (remainder of CWT omitted forbrevity)', "rs_cnf"brevity)/', / rs_cnf / 41 : {"COSE_Key"/ COSE_Key / 1 : {"kty"/ kty / 1 :"EC2", "kid"2 /EC2/, / kid / 2 : h'12',"crv" : "P-256", "x"/ crv / -1 : 1 /P-256/, / x / -2 : h'BCEE7EAAC162F91E6F330F5771211E220 B8B546C96589B0AC4AD0FD24C77E1F1',"y"/ y / -3 : h'C647B38C55EFBBC4E62E651720F002D5D 75B2E0C02CD1326E662BCA222B90416' } } }]]></artwork> </figure></t> </section><!-- AS->C -->]]></sourcecode> </figure> </section> </section><!--Token Endpont--><section anchor="introsp"title="Parametersnumbered="true" toc="default"> <name>Parameters for the IntrospectionEndpoint">Endpoint</name> <t>This section defines the use of CBOR instead of JSON for the"cnf"<tt>cnf</tt> introspection response parameter specified insection 9.4 of<xreftarget="RFC8705"/>.</t>target="RFC8705" sectionFormat="of" section="9.4"/>.</t> <t>If CBOR is used instead of JSON in an interaction with the introspection endpoint, the ASMUST<bcp14>MUST</bcp14> use the parameter mapping specified in <xreftarget="fig:cborParameters"/>target="fig_cborParameters" format="default"/> and the value must follow the syntax of"cnf"<tt>cnf</tt> claim values fromsection 3.1 of<xreftarget="RFC8747"/>.</t>target="RFC8747" sectionFormat="of" section="3.1"/>.</t> <t><xreftarget="fig:introRes"/>target="fig_introRes" format="default"/> shows an AS response to an introspection request including the"cnf"<tt>cnf</tt> parameter to indicate theproof-of-possessionPoP key bound to thetoken.token.</t> <figurealign="center" anchor="fig:introRes" title="Example introspection response."> <artwork align="left"><![CDATA[anchor="fig_introRes"> <name>Example Introspection Response</name> <sourcecode name="" type="cbor-diag"><![CDATA[ Header: Created (Code=2.01) Content-Format:"application/ace+cbor"application/ace+cbor Payload: {"active"/ active / 10 : true,"scope"/ scope / 9 : "read","aud"/ aud / 3 : "tempSensor4711","cnf"/ cnf / 8 : {"COSE_Key"/ COSE_Key / 1 : {"kty"/ kty / 1 :"EC2", "kid"2 /EC2/, / kid / 2 : h'11',"crv" : "P-256", "x"/ crv / -1 : 1 /P-256/, / x / -2 : h'BAC5B11CAD8F99F9C72B05CF4B9E26D24 4DC189F745228255A219A86D6A09EFF',"y"/ y / -3 : h'20138BF82DC1B6D562BE0FA54AB7804A3 A64B6D72CCFED6B6FB6ED28BBFC117E' } } }]]></artwork> </figure></t>]]></sourcecode> </figure> </section><!-- introspection --><section anchor="paramCnf"title="Confirmationnumbered="true" toc="default"> <name>Confirmation MethodParameters">Parameters</name> <t>The confirmation method parameters are used in <xreftarget="I-D.ietf-ace-oauth-authz"/>target="RFC9200" format="default"/> as follows:<list style="symbols"> <t>"req_cnf"</t> <ul spacing="normal"> <li><tt>req_cnf</tt> in the access token request C->-> AS,OPTIONAL<bcp14>OPTIONAL</bcp14> to indicate the client's raw publickey,key or thekey-identifierkey identifier of a previously established key between the C and RS that the client wishes to use forproof-of-possessionproof of possession of the accesstoken.</t> <t>"cnf"token.</li> <li><tt>cnf</tt> in the token response AS->-> C,OPTIONAL<bcp14>OPTIONAL</bcp14> if using an asymmetric key or a key that the client requested via a key identifier in the request.REQUIRED<bcp14>REQUIRED</bcp14> if the client didn't specify a"req_cnf"<tt>req_cnf</tt> and symmetric keys are used. Used to indicate the symmetric key generated by the AS forproof-of-possessionproof of possession of the accesstoken.</t> <t>"cnf"token.</li> <li><tt>cnf</tt> in the introspection response AS->-> RS,REQUIRED<bcp14>REQUIRED</bcp14> if the access token that was subject to introspection is aproof-of-possessionPoP token, absent otherwise. Indicates theproof-of-possessionPoP key bound to the accesstoken.</t> <t>"rs_cnf"token.</li> <li><tt>rs_cnf</tt> in the token response AS->-> C,OPTIONAL<bcp14>OPTIONAL</bcp14> to indicate the public key of theRS,RS if it uses one to authenticate itself to the client and the binding between the key and RS identity is not established through othermeans.</t> </list></t>means.</li> </ul> <t>Note that the COSE_Key structure in a confirmation claim or parameter may contain an"alg"<tt>alg</tt> or"key_ops"<tt>key_ops</tt> parameter. If such parameters are present, a clientMUST NOT<bcp14>MUST NOT</bcp14> use a key that is incompatible with the profile orproof-of-possessionPoP algorithm according to those parameters. An RSMUST<bcp14>MUST</bcp14> reject aproof-of-possessionproof of possession using such a key with a response code equivalent to the CoAP code 4.00 (Bad Request). </t> <t>If an access token is issued for an audience that includes severalRS,RSs, the"rs_cnf"<tt>rs_cnf</tt> parameterMUST NOT<bcp14>MUST NOT</bcp14> be used, since the client cannot determine for which RS the key applies. This document recommends to specify a different endpoint that the client can use to acquire RS authentication keys in such cases. The specification of such an endpoint is out of scope for this document.</t> </section> <section anchor="paramsCbor"title="CBOR Mappings">numbered="true" toc="default"> <name>CBOR Mappings</name> <t>If CBOR is used, the new parameters and claims defined in this documentMUST<bcp14>MUST</bcp14> be mapped to CBORtypestypes, as specified in <xreftarget="fig:cborParameters"/>,target="fig_cborParameters" format="default"/>, using the given integer abbreviation for the mapkey. <figure align="center" anchor="fig:cborParameters" title="CBOR mappingskey.</t> <table anchor="fig_cborParameters" align="left"> <name>CBOR Mappings fornew parametersNew Parameters andclaims."> <artwork align="left"><![CDATA[ /----------+----------+-------------------------------------\ | Name | CBOR Key | Value Type | Usage | |----------+----------+-------------------------------------| | req_cnf | TBD (4) | map | token request | | cnf | TBD (8) | map | token response | | cnf | TBD (8) | map | introspection response | | rs_cnf | TBD (41) | map | token response | \----------+----------+------------+------------------------/ ]]></artwork> </figure> </t>Claims</name> <thead> <tr> <th>Name</th> <th>CBOR Key</th> <th>Value Type</th> <th>Usage</th> </tr> </thead> <tbody> <tr> <td>req_cnf</td> <td>4</td> <td>map</td> <td>token request</td> </tr> <tr> <td>cnf</td> <td>8</td> <td>map</td> <td>token response</td> </tr> <tr> <td>cnf</td> <td>8</td> <td>map</td> <td>introspection response</td> </tr> <tr> <td>rs_cnf</td> <td>41</td> <td>map</td> <td>token response</td> </tr> </tbody> </table> </section> <section anchor="asymmReq"title="Requirements when using asymmetric keys">numbered="true" toc="default"> <name>Requirements When Using Asymmetric Keys</name> <t>An RS using asymmetric keys to authenticate to the clientMUST NOT<bcp14>MUST NOT</bcp14> hold several different asymmetric keypairs,pairs applicable to the same authentication algorithm. Forexampleexample, when using DTLS, the RSMUST NOT<bcp14>MUST NOT</bcp14> hold several asymmetric key pairs applicable to the same cipher suite. The reason for this restriction is that the RS has no way of determining which key to use before the client's identity is established.ThereforeTherefore, authentication attempts by the RS could randomly fail based on which key the RS selects, unless the algorithm negotiation produces a unique choice of key pair for theRS. </t>RS.</t> </section> <section anchor="security"title="Security Considerations">numbered="true" toc="default"> <name>Security Considerations</name> <t>This document is an extension to <xreftarget="I-D.ietf-ace-oauth-authz"/>.target="RFC9200" format="default"/>. All security considerations from that document apply here as well.</t> </section> <section anchor="privacy"title="Privacy Considerations">numbered="true" toc="default"> <name>Privacy Considerations</name> <t>This document is an extension to <xreftarget="I-D.ietf-ace-oauth-authz"/>.target="RFC9200" format="default"/>. All privacy considerations from that document apply here as well.</t> </section> <section anchor="iana"title="IANA Considerations">numbered="true" toc="default"> <name>IANA Considerations</name> <section anchor="IANAOAuthParameter"title="OAuthnumbered="true" toc="default"> <name>OAuth ParameterRegistration">Registration</name> <t>This section registers the following parameters in the "OAuth Parameters" registry <xreftarget="IANA.OAuthParameters"/>:</t> <t><?rfc subcompact="yes"?> <list style='symbols'> <t>Name: <spanx style="verb">req_cnf</spanx></t> <t>Parametertarget="IANA.OAuthParameters" format="default"/>:</t> <dl newline="false" spacing="compact"> <dt>Name:</dt> <dd><tt>req_cnf</tt></dd> <dt>Parameter UsageLocation: token request</t> <t>Change Controller: IESG</t> <t>Reference: <xref target="paramCnf"/> of [this document]</t> </list></t> <t><?rfc subcompact="yes"?> <list style='symbols'> <t>Name: <spanx style="verb">rs_cnf</spanx></t> <t>ParameterLocation:</dt> <dd>token request</dd> <dt>Change Controller:</dt> <dd>IETF</dd> <dt>Reference:</dt> <dd><xref target="paramCnf" format="default"/> of RFC 9201</dd> </dl> <dl newline="false" spacing="compact"> <dt>Name:</dt> <dd><tt>rs_cnf</tt></dd> <dt>Parameter UsageLocation: token response</t> <t>Change Controller: IESG</t> <t>Reference: <xref target="paramCnf"/> of [this document]</t> </list></t> <t><?rfc subcompact="yes"?> <list style='symbols'> <t>Name: <spanx style="verb">cnf</spanx></t> <t>ParameterLocation:</dt> <dd>token response</dd> <dt>Change Controller:</dt> <dd>IETF</dd> <dt>Reference:</dt> <dd><xref target="paramCnf" format="default"/> of RFC 9201</dd> </dl> <dl newline="false" spacing="compact"> <dt>Name:</dt> <dd><tt>cnf</tt></dd> <dt>Parameter UsageLocation: token response</t> <t>Change Controller: IESG</t> <t>Reference: <xref target="paramCnf"/> of [this document]</t> </list></t>Location:</dt> <dd>token response</dd> <dt>Change Controller:</dt> <dd>IETF</dd> <dt>Reference:</dt> <dd><xref target="paramCnf" format="default"/> of RFC 9201</dd> </dl> </section> <section anchor="IANATokenCBORMappingRegistration"title="OAuthnumbered="true" toc="default"> <name>OAuth Parameters CBOR MappingsRegistration">Registration</name> <t>This section registers the following parameter mappings in the "OAuth Parameters CBOR Mappings" registry established insection 8.9. of<xreftarget="I-D.ietf-ace-oauth-authz"/>.</t> <t><?rfc subcompact="yes"?> <list style='symbols'> <t>Name: <spanx style="verb">req_cnf</spanx></t> <t>CBOR key: TBD (suggested: 4)</t> <t>Change Controller: IESG</t> <t>Reference: <xref target="tokenRequest"/> of [this document]</t> </list></t> <t><?rfc subcompact="yes"?> <list style='symbols'> <t>Name: <spanx style="verb">cnf</spanx></t> <t>CBOR key: TBD (suggested: 8)</t> <t>Change Controller: IESG</t> <t>Reference: <xref target="tokenResponse"/> of [this document]</t> </list></t> <t><?rfc subcompact="yes"?> <list style='symbols'> <t>Name: <spanx style="verb">rs_cnf</spanx></t> <t>CBOR key: TBD (suggested: 41)</t> <t>Change Controller: IESG</t> <t>Reference: <xref target="tokenResponse"/> of [this document]</t> </list></t>target="RFC9200" sectionFormat="of" section="8.10"/>.</t> <dl newline="false" spacing="compact"> <dt>Name:</dt> <dd><tt>req_cnf</tt></dd> <dt>CBOR Key:</dt> <dd>4</dd> <dt>Value Type:</dt> <dd>map</dd> <dt>Reference:</dt> <dd><xref target="tokenRequest" format="default"/> of RFC 9201</dd> <dt>Original Specification:</dt> <dd>RFC 9201</dd> </dl> <dl newline="false" spacing="compact"> <dt>Name:</dt> <dd><tt>cnf</tt></dd> <dt>CBOR Key:</dt> <dd>8</dd> <dt>Value Type:</dt> <dd>map</dd> <dt>Reference:</dt> <dd><xref target="tokenResponse" format="default"/> of RFC 9201</dd> <dt>Original Specification:</dt> <dd>RFC 9201</dd> </dl> <dl newline="false" spacing="compact"> <dt>Name:</dt> <dd><tt>rs_cnf</tt></dd> <dt>CBOR Key:</dt> <dd>41</dd> <dt>Value Type:</dt> <dd>map</dd> <dt>Reference:</dt> <dd><xref target="tokenResponse" format="default"/> of RFC 9201</dd> <dt>Original Specification:</dt> <dd>RFC 9201</dd> </dl> </section> <section anchor="IANAIntrospectCBORMappingRegistration"title="OAuthnumbered="true" toc="default"> <name>OAuth Token Introspection Response CBOR MappingsRegistration">Registration</name> <t>This section registers the following parameter mapping in the "OAuth Token Introspection Response CBOR Mappings" registry established insection 8.11. of<xreftarget="I-D.ietf-ace-oauth-authz"/>.</t> <t><?rfc subcompact="yes"?> <list style='symbols'> <t>Name: <spanx style="verb">cnf</spanx></t> <t>CBOR key: TBD (suggested: 8)</t> <t>Change Controller: IESG</t> <t>Reference: <xref target="introsp"/> of [this document]</t> </list></t>target="RFC9200" sectionFormat="of" section="8.12"/>.</t> <dl newline="false" spacing="compact"> <dt>Name:</dt> <dd><tt>cnf</tt></dd> <dt>CBOR Key:</dt> <dd>8</dd> <dt>Value Type:</dt> <dd>map</dd> <dt>Reference:</dt> <dd><xref target="introsp" format="default"/> of RFC 9201</dd> <dt>Original Specification:</dt> <dd><xref target="RFC8705" format="default"/></dd> </dl> </section></section><!-- IANA considerations --></section> </middle> <back> <references> <name>References</name> <references> <name>Normative References</name> <reference anchor='RFC9200' target='https://www.rfc-editor.org/info/rfc9200'> <front> <title>Authentication and Authorization for Constrained Environments (ACE) Using the OAuth 2.0 Framework (ACE-OAuth)</title> <author initials='L' surname='Seitz' fullname='Ludwig Seitz'> <organization /> </author> <author initials='G' surname='Selander' fullname='Göran Selander'> <organization /> </author> <author initials='E' surname='Wahlstroem' fullname='Erik Wahlstroem'> <organization /> </author> <author initials='S' surname='Erdtman' fullname='Samuel Erdtman'> <organization /> </author> <author initials='H' surname='Tschofenig' fullname='Hannes Tschofenig'> <organization /> </author> <date year='2022' month='August'/> </front> <seriesInfo name="RFC" value="9200"/> <seriesInfo name="DOI" value="10.17487/RFC9200"/> </reference> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.2119.xml"/> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.6749.xml"/> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.7800.xml"/> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.8152.xml"/> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.8174.xml"/> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.8259.xml"/> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.8705.xml"/> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.8747.xml"/> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.8949.xml"/> <reference anchor="IANA.OAuthParameters" target="https://www.iana.org/assignments/oauth-parameters"> <front> <title>OAuth Parameters</title> <author> <organization>IANA</organization> </author> </front> </reference> </references> <references> <name>Informative References</name> <xi:include href="https://xml2rfc.ietf.org/public/rfc/bibxml/reference.RFC.7252.xml"/> </references> </references> <section anchor="Acknowledgments"title="Acknowledgments">numbered="false" toc="default"> <name>Acknowledgments</name> <t>This document is a product of the ACEworking groupWorking Group of the IETF. Special thanks toBrian Campbell<contact fullname="Brian Campbell"/> for his thorough review of this document.</t><t>Ludwig Seitz<t><contact fullname="Ludwig Seitz"/> worked on this document as part of the CelticNext projectsCyberWI,CyberWI and CRITISEC with funding from Vinnova.</t> </section><!-- Possibly a 'Contributors' section ... --> </middle> <!-- *****BACK MATTER ***** --> <back> <!-- References split into informative and normative --> <!-- There are 2 ways to insert reference entries from the citation libraries: 1. define an ENTITY at the top, and use "ampersand character"RFC2629; here (as shown) 2. simply use a PI "less than character"?rfc include="reference.RFC.2119.xml"?> here (for I-Ds: include="reference.I-D.narten-iana-considerations-rfc2434bis.xml") Both are cited textually in the same manner: by using xref elements. If you use the PI option, xml2rfc will, by default, try to find included files in the same directory as the including file. You can also define the XML_LIBRARY environment variable with a value containing a set of directories to search. These can be either in the local filing system or remote ones accessed by http (http://domain/dir/... ).--> <references title="Normative References"> <!--?rfc include="http://xml.resource.org/public/rfc/bibxml/reference.RFC.2119.xml"?--> &I-D.ietf-ace-oauth-authz; &RFC2119; &RFC6749; &RFC7800; &RFC8152; &RFC8174; &RFC8259; &RFC8705; &RFC8747; &RFC8949; <reference anchor="IANA.OAuthParameters" target="https://www.iana.org/assignments/oauth-parameters/oauth-parameters.xhtml#parameters"> <front> <title>OAuth Parameters</title> <author> <organization>IANA</organization> </author> <date/> </front> </reference> </references> <references title="Informative References"> &RFC7252; </references></back> </rfc><!-- LocalWords: Combitech Djäknegatan Malmö CoAP CBOR JSON BCP req --> <!-- LocalWords: authz cnf DTLS RPK COSE alg JWT IESG TBD PoP IETF --> <!-- LocalWords: Seitz CelticNext CyberWI CRITISEC Vinnova Ds xml --> <!-- LocalWords: rfc http IANA -->