<?xmlversion="1.0" encoding="UTF-8"?> <?xml-stylesheet type="text/xsl" href="rfc2629.xslt" ?> <!-- generated by https://github.com/cabo/kramdown-rfc2629 version 1.2.9 --> <!DOCTYPE rfc SYSTEM "rfc2629.dtd" [ ]> <?rfc toc="yes"?> <?rfc sortrefs="yes"?> <?rfc symrefs="yes"?>version='1.0' encoding='utf-8'?> <rfcipr="trust200902"xmlns:xi="http://www.w3.org/2001/XInclude" version="3" category="std" consensus="true" docName="draft-ietf-acme-ip-08"category="std">indexInclude="true" ipr="trust200902" number="8738" prepTime="2020-02-28T19:14:01" scripts="Common,Latin" sortRefs="true" submissionType="IETF" symRefs="true" tocDepth="3" tocInclude="true" xml:lang="en"> <link href="https://datatracker.ietf.org/doc/draft-ietf-acme-ip-08" rel="prev"/> <link href="https://dx.doi.org/10.17487/rfc8738" rel="alternate"/> <link href="urn:issn:2070-1721" rel="alternate"/> <front> <titleabbrev="ACME-IP">ACMEabbrev="ACME-IP">Automated Certificate Management Environment (ACME) IP Identifier Validation Extension</title> <seriesInfo name="RFC" value="8738" stream="IETF"/> <author initials="R.B." surname="Shoemaker" fullname="Roland Bracewell Shoemaker"> <organizationabbrev="ISRG">Internetabbrev="ISRG" showOnFrontPage="true">Internet Security Research Group</organization> <address> <email>roland@letsencrypt.org</email> </address> </author> <dateyear="2019" month="October" day="01"/> <area>General</area>month="02" year="2020"/> <area>Security</area> <workgroup>ACME Working Group</workgroup><abstract> <t>This<keyword>acme</keyword> <keyword>pki</keyword> <abstract pn="section-abstract"> <t pn="section-abstract-1">This document specifies identifiers and challenges required to enable the Automated Certificate Management Environment (ACME) to issue certificates for IP addresses.</t> </abstract> <boilerplate> <section anchor="status-of-memo" numbered="false" removeInRFC="false" toc="exclude" pn="section-boilerplate.1"> <name slugifiedName="name-status-of-this-memo">Status of This Memo</name> <t pn="section-boilerplate.1-1"> This is an Internet Standards Track document. </t> <t pn="section-boilerplate.1-2"> This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 7841. </t> <t pn="section-boilerplate.1-3"> Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at <eref target="https://www.rfc-editor.org/info/rfc8738" brackets="none"/>. </t> </section> <section anchor="copyright" numbered="false" removeInRFC="false" toc="exclude" pn="section-boilerplate.2"> <name slugifiedName="name-copyright-notice">Copyright Notice</name> <t pn="section-boilerplate.2-1"> Copyright (c) 2020 IETF Trust and the persons identified as the document authors. All rights reserved. </t> <t pn="section-boilerplate.2-2"> This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (<eref target="https://trustee.ietf.org/license-info" brackets="none"/>) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. </t> </section> </boilerplate> <toc> <section anchor="toc" numbered="false" removeInRFC="false" toc="exclude" pn="section-toc.1"> <name slugifiedName="name-table-of-contents">Table of Contents</name> <ul bare="true" empty="true" indent="2" spacing="compact" pn="section-toc.1-1"> <li pn="section-toc.1-1.1"> <t keepWithNext="true" pn="section-toc.1-1.1.1"><xref derivedContent="1" format="counter" sectionFormat="of" target="section-1"/>. <xref derivedContent="" format="title" sectionFormat="of" target="name-introduction">Introduction</xref></t> </li> <li pn="section-toc.1-1.2"> <t keepWithNext="true" pn="section-toc.1-1.2.1"><xref derivedContent="2" format="counter" sectionFormat="of" target="section-2"/>. <xref derivedContent="" format="title" sectionFormat="of" target="name-terminology">Terminology</xref></t> </li> <li pn="section-toc.1-1.3"> <t keepWithNext="true" pn="section-toc.1-1.3.1"><xref derivedContent="3" format="counter" sectionFormat="of" target="section-3"/>. <xref derivedContent="" format="title" sectionFormat="of" target="name-ip-identifier">IP Identifier</xref></t> </li> <li pn="section-toc.1-1.4"> <t keepWithNext="true" pn="section-toc.1-1.4.1"><xref derivedContent="4" format="counter" sectionFormat="of" target="section-4"/>. <xref derivedContent="" format="title" sectionFormat="of" target="name-identifier-validation-chall">Identifier Validation Challenges</xref></t> </li> <li pn="section-toc.1-1.5"> <t keepWithNext="true" pn="section-toc.1-1.5.1"><xref derivedContent="5" format="counter" sectionFormat="of" target="section-5"/>. <xref derivedContent="" format="title" sectionFormat="of" target="name-http-challenge">HTTP Challenge</xref></t> </li> <li pn="section-toc.1-1.6"> <t keepWithNext="true" pn="section-toc.1-1.6.1"><xref derivedContent="6" format="counter" sectionFormat="of" target="section-6"/>. <xref derivedContent="" format="title" sectionFormat="of" target="name-tls-with-application-layer-">TLS with Application-Layer Protocol Negotiation (TLS ALPN) Challenge</xref></t> </li> <li pn="section-toc.1-1.7"> <t keepWithNext="true" pn="section-toc.1-1.7.1"><xref derivedContent="7" format="counter" sectionFormat="of" target="section-7"/>. <xref derivedContent="" format="title" sectionFormat="of" target="name-dns-challenge">DNS Challenge</xref></t> </li> <li pn="section-toc.1-1.8"> <t keepWithNext="true" pn="section-toc.1-1.8.1"><xref derivedContent="8" format="counter" sectionFormat="of" target="section-8"/>. <xref derivedContent="" format="title" sectionFormat="of" target="name-iana-considerations">IANA Considerations</xref></t> <ul bare="true" empty="true" indent="2" spacing="compact" pn="section-toc.1-1.8.2"> <li pn="section-toc.1-1.8.2.1"> <t keepWithNext="true" pn="section-toc.1-1.8.2.1.1"><xref derivedContent="8.1" format="counter" sectionFormat="of" target="section-8.1"/>. <xref derivedContent="" format="title" sectionFormat="of" target="name-identifier-types">Identifier Types</xref></t> </li> <li pn="section-toc.1-1.8.2.2"> <t keepWithNext="true" pn="section-toc.1-1.8.2.2.1"><xref derivedContent="8.2" format="counter" sectionFormat="of" target="section-8.2"/>. <xref derivedContent="" format="title" sectionFormat="of" target="name-challenge-types">Challenge Types</xref></t> </li> </ul> </li> <li pn="section-toc.1-1.9"> <t keepWithNext="true" pn="section-toc.1-1.9.1"><xref derivedContent="9" format="counter" sectionFormat="of" target="section-9"/>. <xref derivedContent="" format="title" sectionFormat="of" target="name-security-considerations">Security Considerations</xref></t> <ul bare="true" empty="true" indent="2" spacing="compact" pn="section-toc.1-1.9.2"> <li pn="section-toc.1-1.9.2.1"> <t keepWithNext="true" pn="section-toc.1-1.9.2.1.1"><xref derivedContent="9.1" format="counter" sectionFormat="of" target="section-9.1"/>. <xref derivedContent="" format="title" sectionFormat="of" target="name-certification-authority-ca-">Certification Authority (CA) Policy Considerations</xref></t> </li> </ul> </li> <li pn="section-toc.1-1.10"> <t keepWithNext="true" pn="section-toc.1-1.10.1"><xref derivedContent="10" format="counter" sectionFormat="of" target="section-10"/>. <xref derivedContent="" format="title" sectionFormat="of" target="name-normative-references">Normative References</xref></t> </li> <li pn="section-toc.1-1.11"> <t keepWithNext="true" pn="section-toc.1-1.11.1"><xref derivedContent="" format="none" sectionFormat="of" target="section-appendix.a"/><xref derivedContent="" format="title" sectionFormat="of" target="name-acknowledgments">Acknowledgments</xref></t> </li> <li pn="section-toc.1-1.12"> <t keepWithNext="true" pn="section-toc.1-1.12.1"><xref derivedContent="" format="none" sectionFormat="of" target="section-appendix.b"/><xref derivedContent="" format="title" sectionFormat="of" target="name-authors-address">Author's Address</xref></t> </li> </ul> </section> </toc> </front> <middle> <section anchor="introduction"title="Introduction"> <t>Thenumbered="true" toc="include" removeInRFC="false" pn="section-1"> <name slugifiedName="name-introduction">Introduction</name> <t pn="section-1-1">The Automatic Certificate Management Environment (ACME) <xreftarget="RFC8555"/>target="RFC8555" format="default" sectionFormat="of" derivedContent="RFC8555"/> only defines challenges for validating control of DNS host name identifiers, which limits its use to being used for issuing certificates for DNS identifiers. In order to allow validation of IPv4 and IPv6 identifiers for inclusion in X.509 certificates, this document specifies how challenges defined in the original ACME specification and the TLS-ALPN extension specification <xreftarget="I-D.ietf-acme-tls-alpn"/>target="RFC8737" format="default" sectionFormat="of" derivedContent="RFC8737"/> can be used to validate IP identifiers.</t> </section> <section anchor="terminology"title="Terminology"> <t>Thenumbered="true" toc="include" removeInRFC="false" pn="section-2"> <name slugifiedName="name-terminology">Terminology</name> <t pn="section-2-1"> 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" sectionFormat="of" derivedContent="RFC2119"/> <xreftarget="RFC8174"/>target="RFC8174" format="default" sectionFormat="of" derivedContent="RFC8174"/> when, and only when, they appear in all capitals, as shownhere.</t>here. </t> </section> <section anchor="ip-identifier"title="IP Identifier"> <t><xref target="RFC8555"/>numbered="true" toc="include" removeInRFC="false" pn="section-3"> <name slugifiedName="name-ip-identifier">IP Identifier</name> <t pn="section-3-1"><xref target="RFC8555" format="default" sectionFormat="of" derivedContent="RFC8555"/> only defines the identifier type“dns”,"dns", which is used to refer to fully qualified domain names. If an ACME server wishes to request proof that a user controlsaan IPv4 or IPv6 address, itMUST<bcp14>MUST</bcp14> create an authorization with the identifier type“ip”."ip". The value field of the identifierMUST<bcp14>MUST</bcp14> contain the textual form of the address as defined in <xreftarget="RFC1123"/> Section 2.1target="RFC1123" sectionFormat="of" section="2.1" format="default" derivedLink="https://rfc-editor.org/rfc/rfc1123#section-2.1" derivedContent="RFC1123"/> for IPv4 and in <xreftarget="RFC5952"/> Section 4target="RFC5952" sectionFormat="of" section="4" format="default" derivedLink="https://rfc-editor.org/rfc/rfc5952#section-4" derivedContent="RFC5952"/> for IPv6.</t><t>An<t pn="section-3-2">An identifier for the IPv6 address 2001:db8::1 would be formatted like so:</t><figure><artwork><![CDATA[<sourcecode type="json" markers="false" pn="section-3-3"> {"type": "ip", "value": "2001:db8::1"}]]></artwork></figure></sourcecode> </section> <section anchor="identifier-validation-challenges"title="Identifiernumbered="true" toc="include" removeInRFC="false" pn="section-4"> <name slugifiedName="name-identifier-validation-chall">Identifier ValidationChallenges"> <t>IPChallenges</name> <t pn="section-4-1">IP identifiersMAY<bcp14>MAY</bcp14> be used with the existing“http-01”"http-01" (seeSection 8.3 of<xreftarget="RFC8555"/>)target="RFC8555" sectionFormat="of" section="8.3" format="default" derivedLink="https://rfc-editor.org/rfc/rfc8555#section-8.3" derivedContent="RFC8555"/>) and“tls-alpn-01”"tls-alpn-01" (seeSection 3 of<xreftarget="I-D.ietf-acme-tls-alpn"/>).target="RFC8737" sectionFormat="of" section="3" format="default" derivedLink="https://rfc-editor.org/rfc/rfc8737#section-3" derivedContent="RFC8737"/>). To use IP identifiers with these challenges, their initial DNS resolution stepMUST<bcp14>MUST</bcp14> be skipped, and the IP address used for validationMUST<bcp14>MUST</bcp14> be the value of the identifier.</t> </section> <section anchor="http-challenge"title="HTTP Challenge"> <t>Fornumbered="true" toc="include" removeInRFC="false" pn="section-5"> <name slugifiedName="name-http-challenge">HTTP Challenge</name> <t pn="section-5-1">For the“http-01”"http-01" challenge, the Host header fieldMUST<bcp14>MUST</bcp14> be set to the IP address being used for validation per <xreftarget="RFC7230"/>.target="RFC7230" format="default" sectionFormat="of" derivedContent="RFC7230"/>. The textual form of this addressMUST<bcp14>MUST</bcp14> be as defined in <xreftarget="RFC1123"/> Section 2.1target="RFC1123" sectionFormat="of" section="2.1" format="default" derivedLink="https://rfc-editor.org/rfc/rfc1123#section-2.1" derivedContent="RFC1123"/> for IPv4 and in <xreftarget="RFC5952"/> Section 4target="RFC5952" sectionFormat="of" section="4" format="default" derivedLink="https://rfc-editor.org/rfc/rfc5952#section-4" derivedContent="RFC5952"/> for IPv6.</t> </section> <section anchor="tls-with-application-level-protocol-negotiation-tls-alpn-challenge"title="TLSnumbered="true" toc="include" removeInRFC="false" pn="section-6"> <name slugifiedName="name-tls-with-application-layer-">TLS withApplication LevelApplication-Layer Protocol Negotiation (TLS ALPN)Challenge"> <t>ForChallenge</name> <t pn="section-6-1">For the“tls-alpn-01”"tls-alpn-01" challenge, the subjectAltName extension in the validation certificateMUST<bcp14>MUST</bcp14> contain a single iPAddress that matches the address being validated. As <xreftarget="RFC6066"/>target="RFC6066" format="default" sectionFormat="of" derivedContent="RFC6066"/> does not permit IP addresses to be used in theSNIServer Name Indication (SNI) extension HostName field, the serverMUST<bcp14>MUST</bcp14> instead use the IN-ADDR.ARPA <xreftarget="RFC1034"/>target="RFC1034" format="default" sectionFormat="of" derivedContent="RFC1034"/> or IP6.ARPA <xreftarget="RFC3596"/>target="RFC3596" format="default" sectionFormat="of" derivedContent="RFC3596"/> reverse mapping of the IP address as the HostName field value instead of the IP address string representation itself. For example, if the IP address being validated is 2001:db8::1, the SNI HostName field should contain“1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa”.</t>"1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa".</t> </section> <section anchor="dns-challenge"title="DNS Challenge"> <t>Thenumbered="true" toc="include" removeInRFC="false" pn="section-7"> <name slugifiedName="name-dns-challenge">DNS Challenge</name> <t pn="section-7-1">The existing“dns-01”"dns-01" challengeMUST NOT<bcp14>MUST NOT</bcp14> be used to validate IP identifiers.</t> </section> <section anchor="iana-considerations"title="IANA Considerations">numbered="true" toc="include" removeInRFC="false" pn="section-8"> <name slugifiedName="name-iana-considerations">IANA Considerations</name> <section anchor="identifier-types"title="Identifier Types"> <t>Addsnumbered="true" toc="include" removeInRFC="false" pn="section-8.1"> <name slugifiedName="name-identifier-types">Identifier Types</name> <t pn="section-8.1-1">Per this document, a new type has been added to the“ACME"ACME IdentifierTypes”Types" registry defined inSection 9.7.7 of<xreftarget="RFC8555"/>target="RFC8555" sectionFormat="of" section="9.7.7" format="default" derivedLink="https://rfc-editor.org/rfc/rfc8555#section-9.7.7" derivedContent="RFC8555"/> with Label“ip”"ip" and Reference“I-D.ietf-acme-ip”.</t>"RFC 8738".</t> </section> <section anchor="challenge-types"title="Challenge Types"> <t>Addsnumbered="true" toc="include" removeInRFC="false" pn="section-8.2"> <name slugifiedName="name-challenge-types">Challenge Types</name> <t pn="section-8.2-1">Per this document, two new entries have been added to the“ACME"ACME ValidationMethods”Methods" registry defined inSection 9.7.8 of<xreftarget="RFC8555"/>.target="RFC8555" sectionFormat="of" section="9.7.8" format="default" derivedLink="https://rfc-editor.org/rfc/rfc8555#section-9.7.8" derivedContent="RFC8555"/>. These entries are defined below:</t><texttable> <ttcol align='left'>Label</ttcol> <ttcol align='left'>Identifier Type</ttcol> <ttcol align='left'>ACME</ttcol> <ttcol align='left'>Reference</ttcol> <c>http-01</c> <c>ip</c> <c>Y</c> <c>I-D.ietf-acme-ip</c> <c>tls-alpn-01</c> <c>ip</c> <c>Y</c> <c>I-D.ietf-acme-ip</c> </texttable><table align="center" pn="table-1"> <thead> <tr> <th align="left" colspan="1" rowspan="1">Label</th> <th align="left" colspan="1" rowspan="1">Identifier Type</th> <th align="left" colspan="1" rowspan="1">ACME</th> <th align="left" colspan="1" rowspan="1">Reference</th> </tr> </thead> <tbody> <tr> <td align="left" colspan="1" rowspan="1">http-01</td> <td align="left" colspan="1" rowspan="1">ip</td> <td align="left" colspan="1" rowspan="1">Y</td> <td align="left" colspan="1" rowspan="1">RFC 8738</td> </tr> <tr> <td align="left" colspan="1" rowspan="1">tls-alpn-01</td> <td align="left" colspan="1" rowspan="1">ip</td> <td align="left" colspan="1" rowspan="1">Y</td> <td align="left" colspan="1" rowspan="1">RFC 8738</td> </tr> </tbody> </table> </section> </section> <section anchor="security-considerations"title="Security Considerations"> <t>Thenumbered="true" toc="include" removeInRFC="false" pn="section-9"> <name slugifiedName="name-security-considerations">Security Considerations</name> <t pn="section-9-1">The extensions to ACME described in this document do not deviate from the broader threat model described in <xreftarget="RFC8555"/> Section 10.1.</t>target="RFC8555" sectionFormat="of" section="10.1" format="default" derivedLink="https://rfc-editor.org/rfc/rfc8555#section-10.1" derivedContent="RFC8555"/>.</t> <section anchor="ca-policy-considerations"title="CAnumbered="true" toc="include" removeInRFC="false" pn="section-9.1"> <name slugifiedName="name-certification-authority-ca-">Certification Authority (CA) PolicyConsiderations"> <t>ThisConsiderations</name> <t pn="section-9.1-1">This document only specifies howaan ACME server may validate that a certificate applicant controlsaan IP identifier at the time of validation. The CA may wish to perform additional checks not specified in this document. For example, if the CA believes an IP identifier belongs toaan ISP or cloud service provider with short delegation periods, they may wish to impose additional restrictions on certificates requested for that identifier.</t> </section> </section><section anchor="acknowledgments" title="Acknowledgments"> <t>The author would like to thank those who contributed to this document and offered editorial and technical input, especially Jacob Hoffman-Andrews and Daniel McCarney.</t> </section></middle> <back> <referencestitle='Normative References'>pn="section-10"> <name slugifiedName="name-normative-references">Normative References</name> <reference anchor="RFC1034"target='https://www.rfc-editor.org/info/rfc1034'>target="https://www.rfc-editor.org/info/rfc1034" quoteTitle="true" derivedAnchor="RFC1034"> <front> <title>Domain names - concepts and facilities</title> <authorinitials='P.V.' surname='Mockapetris' fullname='P.V. Mockapetris'><organization /></author>initials="P.V." surname="Mockapetris" fullname="P.V. Mockapetris"> <organization showOnFrontPage="true"/> </author> <dateyear='1987' month='November' /> <abstract><t>Thisyear="1987" month="November"/> <abstract> <t>This RFC is the revised basic definition of The Domain Name System. It obsoletes RFC-882. This memo describes the domain style names and their used for host address look up and electronic mail forwarding. It discusses the clients and servers in the domain name system and the protocol used betweenthem.</t></abstract>them.</t> </abstract> </front> <seriesInfoname='STD' value='13'/>name="STD" value="13"/> <seriesInfoname='RFC' value='1034'/>name="RFC" value="1034"/> <seriesInfoname='DOI' value='10.17487/RFC1034'/>name="DOI" value="10.17487/RFC1034"/> </reference> <reference anchor="RFC1123"target='https://www.rfc-editor.org/info/rfc1123'>target="https://www.rfc-editor.org/info/rfc1123" quoteTitle="true" derivedAnchor="RFC1123"> <front> <title>Requirements for Internet Hosts - Application and Support</title> <authorinitials='R.' surname='Braden' fullname='R. Braden' role='editor'><organization /></author>initials="R." surname="Braden" fullname="R. Braden" role="editor"> <organization showOnFrontPage="true"/> </author> <dateyear='1989' month='October' /> <abstract><t>Thisyear="1989" month="October"/> <abstract> <t>This RFC is an official specification for the Internet community. It incorporates by reference, amends, corrects, and supplements the primary protocol standards documents relating to hosts.[STANDARDS-TRACK]</t></abstract>[STANDARDS-TRACK]</t> </abstract> </front> <seriesInfoname='STD' value='3'/>name="STD" value="3"/> <seriesInfoname='RFC' value='1123'/>name="RFC" value="1123"/> <seriesInfoname='DOI' value='10.17487/RFC1123'/>name="DOI" value="10.17487/RFC1123"/> </reference> <reference anchor="RFC2119"target='https://www.rfc-editor.org/info/rfc2119'>target="https://www.rfc-editor.org/info/rfc2119" quoteTitle="true" derivedAnchor="RFC2119"> <front> <title>Key words for use in RFCs to Indicate Requirement Levels</title> <authorinitials='S.' surname='Bradner' fullname='S. Bradner'><organization /></author>initials="S." surname="Bradner" fullname="S. Bradner"> <organization showOnFrontPage="true"/> </author> <dateyear='1997' month='March' /> <abstract><t>Inyear="1997" month="March"/> <abstract> <t>In many standards track documents several words are used to signify the requirements in the specification. These words are often capitalized. This document defines these words as they should be interpreted in IETF documents. This document specifies an Internet Best Current Practices for the Internet Community, and requests discussion and suggestions forimprovements.</t></abstract>improvements.</t> </abstract> </front> <seriesInfoname='BCP' value='14'/>name="BCP" value="14"/> <seriesInfoname='RFC' value='2119'/>name="RFC" value="2119"/> <seriesInfoname='DOI' value='10.17487/RFC2119'/>name="DOI" value="10.17487/RFC2119"/> </reference> <reference anchor="RFC3596"target='https://www.rfc-editor.org/info/rfc3596'>target="https://www.rfc-editor.org/info/rfc3596" quoteTitle="true" derivedAnchor="RFC3596"> <front> <title>DNS Extensions to Support IP Version 6</title> <authorinitials='S.' surname='Thomson' fullname='S. Thomson'><organization /></author>initials="S." surname="Thomson" fullname="S. Thomson"> <organization showOnFrontPage="true"/> </author> <authorinitials='C.' surname='Huitema' fullname='C. Huitema'><organization /></author>initials="C." surname="Huitema" fullname="C. Huitema"> <organization showOnFrontPage="true"/> </author> <authorinitials='V.' surname='Ksinant' fullname='V. Ksinant'><organization /></author>initials="V." surname="Ksinant" fullname="V. Ksinant"> <organization showOnFrontPage="true"/> </author> <authorinitials='M.' surname='Souissi' fullname='M. Souissi'><organization /></author>initials="M." surname="Souissi" fullname="M. Souissi"> <organization showOnFrontPage="true"/> </author> <dateyear='2003' month='October' /> <abstract><t>Thisyear="2003" month="October"/> <abstract> <t>This document defines the changes that need to be made to the Domain Name System (DNS) to support hosts running IP version 6 (IPv6). The changes include a resource record type to store an IPv6 address, a domain to support lookups based on an IPv6 address, and updated definitions of existing query types that return Internet addresses as part of additional section processing. The extensions are designed to be compatible with existing applications and, in particular, DNS implementations themselves.[STANDARDS-TRACK]</t></abstract>[STANDARDS-TRACK]</t> </abstract> </front> <seriesInfoname='STD' value='88'/>name="STD" value="88"/> <seriesInfoname='RFC' value='3596'/>name="RFC" value="3596"/> <seriesInfoname='DOI' value='10.17487/RFC3596'/>name="DOI" value="10.17487/RFC3596"/> </reference> <reference anchor="RFC5952"target='https://www.rfc-editor.org/info/rfc5952'>target="https://www.rfc-editor.org/info/rfc5952" quoteTitle="true" derivedAnchor="RFC5952"> <front> <title>A Recommendation for IPv6 Address Text Representation</title> <authorinitials='S.' surname='Kawamura' fullname='S. Kawamura'><organization /></author>initials="S." surname="Kawamura" fullname="S. Kawamura"> <organization showOnFrontPage="true"/> </author> <authorinitials='M.' surname='Kawashima' fullname='M. Kawashima'><organization /></author>initials="M." surname="Kawashima" fullname="M. Kawashima"> <organization showOnFrontPage="true"/> </author> <dateyear='2010' month='August' /> <abstract><t>Asyear="2010" month="August"/> <abstract> <t>As IPv6 deployment increases, there will be a dramatic increase in the need to use IPv6 addresses in text. While the IPv6 address architecture in Section 2.2 of RFC 4291 describes a flexible model for text representation of an IPv6 address, this flexibility has been causing problems for operators, system engineers, and users. This document defines a canonical textual representation format. It does not define a format for internal storage, such as within an application or database. It is expected that the canonical format will be followed by humans and systems when representing IPv6 addresses as text, but all implementations must accept and be able to handle any legitimate RFC 4291 format.[STANDARDS-TRACK]</t></abstract>[STANDARDS-TRACK]</t> </abstract> </front> <seriesInfoname='RFC' value='5952'/>name="RFC" value="5952"/> <seriesInfoname='DOI' value='10.17487/RFC5952'/>name="DOI" value="10.17487/RFC5952"/> </reference> <reference anchor="RFC6066"target='https://www.rfc-editor.org/info/rfc6066'>target="https://www.rfc-editor.org/info/rfc6066" quoteTitle="true" derivedAnchor="RFC6066"> <front> <title>Transport Layer Security (TLS) Extensions: Extension Definitions</title> <authorinitials='D.' surname='Eastlake 3rd' fullname='D.initials="D." surname="Eastlake 3rd" fullname="D. Eastlake3rd'><organization /></author>3rd"> <organization showOnFrontPage="true"/> </author> <dateyear='2011' month='January' /> <abstract><t>Thisyear="2011" month="January"/> <abstract> <t>This document provides specifications for existing TLS extensions. It is a companion document for RFC 5246,"The"The Transport Layer Security (TLS) Protocol Version1.2".1.2". The extensions specified are server_name, max_fragment_length, client_certificate_url, trusted_ca_keys, truncated_hmac, and status_request.[STANDARDS-TRACK]</t></abstract>[STANDARDS-TRACK]</t> </abstract> </front> <seriesInfoname='RFC' value='6066'/>name="RFC" value="6066"/> <seriesInfoname='DOI' value='10.17487/RFC6066'/>name="DOI" value="10.17487/RFC6066"/> </reference> <reference anchor="RFC7230"target='https://www.rfc-editor.org/info/rfc7230'>target="https://www.rfc-editor.org/info/rfc7230" quoteTitle="true" derivedAnchor="RFC7230"> <front> <title>Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing</title> <authorinitials='R.' surname='Fielding' fullname='R. Fielding' role='editor'><organization /></author>initials="R." surname="Fielding" fullname="R. Fielding" role="editor"> <organization showOnFrontPage="true"/> </author> <authorinitials='J.' surname='Reschke' fullname='J. Reschke' role='editor'><organization /></author>initials="J." surname="Reschke" fullname="J. Reschke" role="editor"> <organization showOnFrontPage="true"/> </author> <dateyear='2014' month='June' /> <abstract><t>Theyear="2014" month="June"/> <abstract> <t>The Hypertext Transfer Protocol (HTTP) is a stateless application-level protocol for distributed, collaborative, hypertext information systems. This document provides an overview of HTTP architecture and its associated terminology, defines the"http""http" and"https""https" Uniform Resource Identifier (URI) schemes, defines the HTTP/1.1 message syntax and parsing requirements, and describes related security concerns forimplementations.</t></abstract>implementations.</t> </abstract> </front> <seriesInfoname='RFC' value='7230'/>name="RFC" value="7230"/> <seriesInfoname='DOI' value='10.17487/RFC7230'/>name="DOI" value="10.17487/RFC7230"/> </reference> <reference anchor="RFC8174"target='https://www.rfc-editor.org/info/rfc8174'>target="https://www.rfc-editor.org/info/rfc8174" quoteTitle="true" derivedAnchor="RFC8174"> <front> <title>Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words</title> <authorinitials='B.' surname='Leiba' fullname='B. Leiba'><organization /></author>initials="B." surname="Leiba" fullname="B. Leiba"> <organization showOnFrontPage="true"/> </author> <dateyear='2017' month='May' /> <abstract><t>RFCyear="2017" month="May"/> <abstract> <t>RFC 2119 specifies common key words that may be used in protocol specifications. This document aims to reduce the ambiguity by clarifying that only UPPERCASE usage of the key words have the defined specialmeanings.</t></abstract>meanings.</t> </abstract> </front> <seriesInfoname='BCP' value='14'/>name="BCP" value="14"/> <seriesInfoname='RFC' value='8174'/>name="RFC" value="8174"/> <seriesInfoname='DOI' value='10.17487/RFC8174'/>name="DOI" value="10.17487/RFC8174"/> </reference> <reference anchor="RFC8555"target='https://www.rfc-editor.org/info/rfc8555'>target="https://www.rfc-editor.org/info/rfc8555" quoteTitle="true" derivedAnchor="RFC8555"> <front> <title>Automatic Certificate Management Environment (ACME)</title> <authorinitials='R.' surname='Barnes' fullname='R. Barnes'><organization /></author>initials="R." surname="Barnes" fullname="R. Barnes"> <organization showOnFrontPage="true"/> </author> <authorinitials='J.' surname='Hoffman-Andrews' fullname='J. Hoffman-Andrews'><organization /></author>initials="J." surname="Hoffman-Andrews" fullname="J. Hoffman-Andrews"> <organization showOnFrontPage="true"/> </author> <authorinitials='D.' surname='McCarney' fullname='D. McCarney'><organization /></author>initials="D." surname="McCarney" fullname="D. McCarney"> <organization showOnFrontPage="true"/> </author> <authorinitials='J.' surname='Kasten' fullname='J. Kasten'><organization /></author>initials="J." surname="Kasten" fullname="J. Kasten"> <organization showOnFrontPage="true"/> </author> <dateyear='2019' month='March' /> <abstract><t>Publicyear="2019" month="March"/> <abstract> <t>Public Key Infrastructure using X.509 (PKIX) certificates are used for a number of purposes, the most significant of which is the authentication of domain names. Thus, certification authorities (CAs) in the Web PKI are trusted to verify that an applicant for a certificate legitimately represents the domain name(s) in the certificate. As of this writing, this verification is done through a collection of ad hoc mechanisms. This document describes a protocol that a CA and an applicant can use to automate the process of verification and certificate issuance. The protocol also provides facilities for other certificate management functions, such as certificaterevocation.</t></abstract>revocation.</t> </abstract> </front> <seriesInfoname='RFC' value='8555'/>name="RFC" value="8555"/> <seriesInfoname='DOI' value='10.17487/RFC8555'/>name="DOI" value="10.17487/RFC8555"/> </reference> <referenceanchor="I-D.ietf-acme-tls-alpn">anchor="RFC8737" target="https://www.rfc-editor.org/info/rfc8737" quoteTitle="true" derivedAnchor="RFC8737"> <front><title>ACME<title>Automated Certificate Management Environment (ACME) TLSALPNApplication-Layer Protocol Negotiation (ALPN) Challenge Extension</title> <authorinitials='R' surname='Shoemaker' fullname='Roland Shoemaker'>initials="R.B." surname="Shoemaker" fullname="Roland Bracewell Shoemaker"> <organization/>showOnFrontPage="true"/> </author> <datemonth='September' day='5' year='2019' /> <abstract><t>This document specifies a new challenge for the Automated Certificate Management Environment (ACME) protocol which allows for domain control validation using TLS.</t></abstract>month="February" year="2020"/> </front> <seriesInfoname='Internet-Draft' value='draft-ietf-acme-tls-alpn-06' /> <format type='TXT' target='http://www.ietf.org/internet-drafts/draft-ietf-acme-tls-alpn-06.txt' />name="RFC" value="8737"/> <seriesInfo name="DOI" value="10.17487/RFC8737"/> </reference> </references> <section anchor="acknowledgments" numbered="false" toc="include" removeInRFC="false" pn="section-appendix.a"> <name slugifiedName="name-acknowledgments">Acknowledgments</name> <t pn="section-appendix.a-1">The author would like to thank those who contributed to this document and offered editorial and technical input, especially <contact fullname="Jacob Hoffman-Andrews"/> and <contact fullname="Daniel McCarney"/>.</t> </section> <section anchor="authors-addresses" numbered="false" removeInRFC="false" toc="include" pn="section-appendix.b"> <name slugifiedName="name-authors-address">Author's Address</name> <author initials="R.B." surname="Shoemaker" fullname="Roland Bracewell Shoemaker"> <organization abbrev="ISRG" showOnFrontPage="true">Internet Security Research Group</organization> <address> <email>roland@letsencrypt.org</email> </address> </author> </section> </back><!-- ##markdown-source: H4sIALyOk10AA7VYUXPbuBF+569AlZdkxuJYduzYeqpi+xLd2LIqO21vOp0O REIiagrgAZAV1fb99vsWAClS9s1cHqpMIogkFrvffvvtMv1+P3HSlWLIeqOL mys2nrJxLpSTCykM+zsvZc6d1IpdfXdCWax6CZ/PjXgcMtrQH0+TXGeKr2Ai N3zh+lK4RZ9nK9GXVf/wLMm4E0tttkNmXZ4ksjJD5szauqPDw/PDo4QbwYfs i1DC8DLZaPOwNHpdBfvsH/gt1ZJ9oWtJYh1X+X94qRXO2wqbVHLI/uV0dsCs Ns6IhcVqu6LFv5OEr12hzTBh/YThI5UdslnKPqfsrtBixR+E8TeC/zNdwjr7 bHgmNqIs9x7SZjlkY+WEUcKxO5GtjXRbNhNWcJMV0UV6skZofDf74i/AiiyH zPgD/loKZ4XKzLZyKYwmidJmBZgfBTxls58uBofHH+vl4Og4Lo8Gg/O4PD45 P43Lk/OTo7g8PTytr346Oj6My7PBp9rY2cnJCS3H/ct0lyZX2j4vKzVMkn6/ D+etAwIuSe4LaRmyu16BEcxWIiNaWCYbhlhGgGUFL0uhlrhlxK9raUTOnGZC 8XkpmCsEG62dRoS4fiEMbSVSsBuu+FJ441fqURqt/Po9Jf4DWZDWrgXLdlss 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