source: draft-ietf-httpbis/19/p7-auth.html

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483</style><link rel="Contents" href="#rfc.toc">
484      <link rel="Author" href="#rfc.authors">
485      <link rel="Copyright" href="#rfc.copyrightnotice">
486      <link rel="Index" href="#rfc.index">
487      <link rel="Chapter" title="1 Introduction" href="#rfc.section.1">
488      <link rel="Chapter" title="2 Access Authentication Framework" href="#rfc.section.2">
489      <link rel="Chapter" title="3 Status Code Definitions" href="#rfc.section.3">
490      <link rel="Chapter" title="4 Header Field Definitions" href="#rfc.section.4">
491      <link rel="Chapter" title="5 IANA Considerations" href="#rfc.section.5">
492      <link rel="Chapter" title="6 Security Considerations" href="#rfc.section.6">
493      <link rel="Chapter" title="7 Acknowledgments" href="#rfc.section.7">
494      <link rel="Chapter" href="#rfc.section.8" title="8 References">
495      <link rel="Appendix" title="A Changes from RFCs 2616 and 2617" href="#rfc.section.A">
496      <link rel="Appendix" title="B Collected ABNF" href="#rfc.section.B">
497      <link rel="Appendix" title="C Change Log (to be removed by RFC Editor before publication)" href="#rfc.section.C">
498      <link href="p6-cache.html" rel="prev">
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500      <link rel="schema.dct" href="http://purl.org/dc/terms/">
501      <meta name="dct.creator" content="Fielding, R.">
502      <meta name="dct.creator" content="Lafon, Y.">
503      <meta name="dct.creator" content="Reschke, J. F.">
504      <meta name="dct.identifier" content="urn:ietf:id:draft-ietf-httpbis-p7-auth-19">
505      <meta name="dct.issued" scheme="ISO8601" content="2012-03-12">
506      <meta name="dct.replaces" content="urn:ietf:rfc:2616">
507      <meta name="dct.abstract" content="The Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypermedia information systems. HTTP has been in use by the World Wide Web global information initiative since 1990. This document is Part 7 of the seven-part specification that defines the protocol referred to as &#34;HTTP/1.1&#34; and, taken together, obsoletes RFC 2616. Part 7 defines the HTTP Authentication framework.">
508      <meta name="description" content="The Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypermedia information systems. HTTP has been in use by the World Wide Web global information initiative since 1990. This document is Part 7 of the seven-part specification that defines the protocol referred to as &#34;HTTP/1.1&#34; and, taken together, obsoletes RFC 2616. Part 7 defines the HTTP Authentication framework.">
509   </head>
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511      <table class="header">
512         <tbody>
513            <tr>
514               <td class="left">HTTPbis Working Group</td>
515               <td class="right">R. Fielding, Editor</td>
516            </tr>
517            <tr>
518               <td class="left">Internet-Draft</td>
519               <td class="right">Adobe</td>
520            </tr>
521            <tr>
522               <td class="left">Obsoletes: <a href="https://tools.ietf.org/html/rfc2616">2616</a> (if approved)
523               </td>
524               <td class="right">Y. Lafon, Editor</td>
525            </tr>
526            <tr>
527               <td class="left">Updates: <a href="https://tools.ietf.org/html/rfc2617">2617</a> (if approved)
528               </td>
529               <td class="right">W3C</td>
530            </tr>
531            <tr>
532               <td class="left">Intended status: Standards Track</td>
533               <td class="right">J. Reschke, Editor</td>
534            </tr>
535            <tr>
536               <td class="left">Expires: September 13, 2012</td>
537               <td class="right">greenbytes</td>
538            </tr>
539            <tr>
540               <td class="left"></td>
541               <td class="right">March 12, 2012</td>
542            </tr>
543         </tbody>
544      </table>
545      <p class="title">HTTP/1.1, part 7: Authentication<br><span class="filename">draft-ietf-httpbis-p7-auth-19</span></p>
546      <h1 id="rfc.abstract"><a href="#rfc.abstract">Abstract</a></h1>
547      <p>The Hypertext Transfer Protocol (HTTP) is an application-level protocol for distributed, collaborative, hypermedia information
548         systems. HTTP has been in use by the World Wide Web global information initiative since 1990. This document is Part 7 of the
549         seven-part specification that defines the protocol referred to as "HTTP/1.1" and, taken together, obsoletes RFC 2616.
550      </p>
551      <p>Part 7 defines the HTTP Authentication framework.</p>
552      <h1 id="rfc.note.1"><a href="#rfc.note.1">Editorial Note (To be removed by RFC Editor)</a></h1>
553      <p>Discussion of this draft should take place on the HTTPBIS working group mailing list (ietf-http-wg@w3.org), which is archived
554         at &lt;<a href="http://lists.w3.org/Archives/Public/ietf-http-wg/">http://lists.w3.org/Archives/Public/ietf-http-wg/</a>&gt;.
555      </p>
556      <p>The current issues list is at &lt;<a href="http://tools.ietf.org/wg/httpbis/trac/report/3">http://tools.ietf.org/wg/httpbis/trac/report/3</a>&gt; and related documents (including fancy diffs) can be found at &lt;<a href="http://tools.ietf.org/wg/httpbis/">http://tools.ietf.org/wg/httpbis/</a>&gt;.
557      </p>
558      <p>The changes in this draft are summarized in <a href="#changes.since.18" title="Since draft-ietf-httpbis-p7-auth-18">Appendix&nbsp;C.20</a>.
559      </p>
560      <div id="rfc.status">
561         <h1><a href="#rfc.status">Status of This Memo</a></h1>
562         <p>This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.</p>
563         <p>Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute
564            working documents as Internet-Drafts. The list of current Internet-Drafts is at <a href="http://datatracker.ietf.org/drafts/current/">http://datatracker.ietf.org/drafts/current/</a>.
565         </p>
566         <p>Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other
567            documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as “work
568            in progress”.
569         </p>
570         <p>This Internet-Draft will expire on September 13, 2012.</p>
571      </div>
572      <div id="rfc.copyrightnotice">
573         <h1><a href="#rfc.copyrightnotice">Copyright Notice</a></h1>
574         <p>Copyright © 2012 IETF Trust and the persons identified as the document authors. All rights reserved.</p>
575         <p>This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (<a href="http://trustee.ietf.org/license-info">http://trustee.ietf.org/license-info</a>) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights
576            and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License
577            text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified
578            BSD License.
579         </p>
580         <p>This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November
581            10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to
582            allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s)
583            controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative
584            works of it may not be created outside the IETF Standards Process, except to format it for publication as an RFC or to translate
585            it into languages other than English.
586         </p>
587      </div>
588      <hr class="noprint">
589      <h1 class="np" id="rfc.toc"><a href="#rfc.toc">Table of Contents</a></h1>
590      <ul class="toc">
591         <li><a href="#rfc.section.1">1.</a>&nbsp;&nbsp;&nbsp;<a href="#introduction">Introduction</a><ul>
592               <li><a href="#rfc.section.1.1">1.1</a>&nbsp;&nbsp;&nbsp;<a href="#intro.conformance.and.error.handling">Conformance and Error Handling</a></li>
593               <li><a href="#rfc.section.1.2">1.2</a>&nbsp;&nbsp;&nbsp;<a href="#notation">Syntax Notation</a><ul>
594                     <li><a href="#rfc.section.1.2.1">1.2.1</a>&nbsp;&nbsp;&nbsp;<a href="#core.rules">Core Rules</a></li>
595                  </ul>
596               </li>
597            </ul>
598         </li>
599         <li><a href="#rfc.section.2">2.</a>&nbsp;&nbsp;&nbsp;<a href="#access.authentication.framework">Access Authentication Framework</a><ul>
600               <li><a href="#rfc.section.2.1">2.1</a>&nbsp;&nbsp;&nbsp;<a href="#challenge.and.response">Challenge and Response</a></li>
601               <li><a href="#rfc.section.2.2">2.2</a>&nbsp;&nbsp;&nbsp;<a href="#protection.space">Protection Space (Realm)</a></li>
602               <li><a href="#rfc.section.2.3">2.3</a>&nbsp;&nbsp;&nbsp;<a href="#authentication.scheme.registry">Authentication Scheme Registry</a><ul>
603                     <li><a href="#rfc.section.2.3.1">2.3.1</a>&nbsp;&nbsp;&nbsp;<a href="#considerations.for.new.authentication.schemes">Considerations for New Authentication Schemes</a></li>
604                  </ul>
605               </li>
606            </ul>
607         </li>
608         <li><a href="#rfc.section.3">3.</a>&nbsp;&nbsp;&nbsp;<a href="#status.code.definitions">Status Code Definitions</a><ul>
609               <li><a href="#rfc.section.3.1">3.1</a>&nbsp;&nbsp;&nbsp;<a href="#status.401">401 Unauthorized</a></li>
610               <li><a href="#rfc.section.3.2">3.2</a>&nbsp;&nbsp;&nbsp;<a href="#status.407">407 Proxy Authentication Required</a></li>
611            </ul>
612         </li>
613         <li><a href="#rfc.section.4">4.</a>&nbsp;&nbsp;&nbsp;<a href="#header.field.definitions">Header Field Definitions</a><ul>
614               <li><a href="#rfc.section.4.1">4.1</a>&nbsp;&nbsp;&nbsp;<a href="#header.authorization">Authorization</a></li>
615               <li><a href="#rfc.section.4.2">4.2</a>&nbsp;&nbsp;&nbsp;<a href="#header.proxy-authenticate">Proxy-Authenticate</a></li>
616               <li><a href="#rfc.section.4.3">4.3</a>&nbsp;&nbsp;&nbsp;<a href="#header.proxy-authorization">Proxy-Authorization</a></li>
617               <li><a href="#rfc.section.4.4">4.4</a>&nbsp;&nbsp;&nbsp;<a href="#header.www-authenticate">WWW-Authenticate</a></li>
618            </ul>
619         </li>
620         <li><a href="#rfc.section.5">5.</a>&nbsp;&nbsp;&nbsp;<a href="#IANA.considerations">IANA Considerations</a><ul>
621               <li><a href="#rfc.section.5.1">5.1</a>&nbsp;&nbsp;&nbsp;<a href="#authentication.scheme.registration">Authenticaton Scheme Registry</a></li>
622               <li><a href="#rfc.section.5.2">5.2</a>&nbsp;&nbsp;&nbsp;<a href="#status.code.registration">Status Code Registration</a></li>
623               <li><a href="#rfc.section.5.3">5.3</a>&nbsp;&nbsp;&nbsp;<a href="#header.field.registration">Header Field Registration</a></li>
624            </ul>
625         </li>
626         <li><a href="#rfc.section.6">6.</a>&nbsp;&nbsp;&nbsp;<a href="#security.considerations">Security Considerations</a><ul>
627               <li><a href="#rfc.section.6.1">6.1</a>&nbsp;&nbsp;&nbsp;<a href="#auth.credentials.and.idle.clients">Authentication Credentials and Idle Clients</a></li>
628            </ul>
629         </li>
630         <li><a href="#rfc.section.7">7.</a>&nbsp;&nbsp;&nbsp;<a href="#acks">Acknowledgments</a></li>
631         <li><a href="#rfc.section.8">8.</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.references">References</a><ul>
632               <li><a href="#rfc.section.8.1">8.1</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.references.1">Normative References</a></li>
633               <li><a href="#rfc.section.8.2">8.2</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.references.2">Informative References</a></li>
634            </ul>
635         </li>
636         <li><a href="#rfc.section.A">A.</a>&nbsp;&nbsp;&nbsp;<a href="#changes.from.rfc.2616">Changes from RFCs 2616 and 2617</a></li>
637         <li><a href="#rfc.section.B">B.</a>&nbsp;&nbsp;&nbsp;<a href="#collected.abnf">Collected ABNF</a></li>
638         <li><a href="#rfc.section.C">C.</a>&nbsp;&nbsp;&nbsp;<a href="#change.log">Change Log (to be removed by RFC Editor before publication)</a><ul>
639               <li><a href="#rfc.section.C.1">C.1</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.section.C.1">Since RFC 2616</a></li>
640               <li><a href="#rfc.section.C.2">C.2</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.section.C.2">Since draft-ietf-httpbis-p7-auth-00</a></li>
641               <li><a href="#rfc.section.C.3">C.3</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.section.C.3">Since draft-ietf-httpbis-p7-auth-01</a></li>
642               <li><a href="#rfc.section.C.4">C.4</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.02">Since draft-ietf-httpbis-p7-auth-02</a></li>
643               <li><a href="#rfc.section.C.5">C.5</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.03">Since draft-ietf-httpbis-p7-auth-03</a></li>
644               <li><a href="#rfc.section.C.6">C.6</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.04">Since draft-ietf-httpbis-p7-auth-04</a></li>
645               <li><a href="#rfc.section.C.7">C.7</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.05">Since draft-ietf-httpbis-p7-auth-05</a></li>
646               <li><a href="#rfc.section.C.8">C.8</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.06">Since draft-ietf-httpbis-p7-auth-06</a></li>
647               <li><a href="#rfc.section.C.9">C.9</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.07">Since draft-ietf-httpbis-p7-auth-07</a></li>
648               <li><a href="#rfc.section.C.10">C.10</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.08">Since draft-ietf-httpbis-p7-auth-08</a></li>
649               <li><a href="#rfc.section.C.11">C.11</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.09">Since draft-ietf-httpbis-p7-auth-09</a></li>
650               <li><a href="#rfc.section.C.12">C.12</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.10">Since draft-ietf-httpbis-p7-auth-10</a></li>
651               <li><a href="#rfc.section.C.13">C.13</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.11">Since draft-ietf-httpbis-p7-auth-11</a></li>
652               <li><a href="#rfc.section.C.14">C.14</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.12">Since draft-ietf-httpbis-p7-auth-12</a></li>
653               <li><a href="#rfc.section.C.15">C.15</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.13">Since draft-ietf-httpbis-p7-auth-13</a></li>
654               <li><a href="#rfc.section.C.16">C.16</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.14">Since draft-ietf-httpbis-p7-auth-14</a></li>
655               <li><a href="#rfc.section.C.17">C.17</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.15">Since draft-ietf-httpbis-p7-auth-15</a></li>
656               <li><a href="#rfc.section.C.18">C.18</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.16">Since draft-ietf-httpbis-p7-auth-16</a></li>
657               <li><a href="#rfc.section.C.19">C.19</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.17">Since draft-ietf-httpbis-p7-auth-17</a></li>
658               <li><a href="#rfc.section.C.20">C.20</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.18">Since draft-ietf-httpbis-p7-auth-18</a></li>
659            </ul>
660         </li>
661         <li><a href="#rfc.index">Index</a></li>
662         <li><a href="#rfc.authors">Authors' Addresses</a></li>
663      </ul>
664      <div id="introduction">
665         <h1 id="rfc.section.1" class="np"><a href="#rfc.section.1">1.</a>&nbsp;<a href="#introduction">Introduction</a></h1>
666         <p id="rfc.section.1.p.1">This document defines HTTP/1.1 access control and authentication. It includes the relevant parts of <cite title="Hypertext Transfer Protocol -- HTTP/1.1" id="rfc.xref.RFC2616.1">RFC 2616</cite> with only minor changes, plus the general framework for HTTP authentication, as previously defined in "HTTP Authentication:
667            Basic and Digest Access Authentication" (<a href="#RFC2617" id="rfc.xref.RFC2617.1"><cite title="HTTP Authentication: Basic and Digest Access Authentication">[RFC2617]</cite></a>).
668         </p>
669         <p id="rfc.section.1.p.2">HTTP provides several <em class="bcp14">OPTIONAL</em> challenge-response authentication mechanisms which can be used by a server to challenge a client request and by a client to
670            provide authentication information. The "basic" and "digest" authentication schemes continue to be specified in <cite title="HTTP Authentication: Basic and Digest Access Authentication" id="rfc.xref.RFC2617.2">RFC 2617</cite>.
671         </p>
672         <div id="intro.conformance.and.error.handling">
673            <h2 id="rfc.section.1.1"><a href="#rfc.section.1.1">1.1</a>&nbsp;<a href="#intro.conformance.and.error.handling">Conformance and Error Handling</a></h2>
674            <p id="rfc.section.1.1.p.1">The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL"
675               in this document are to be interpreted as described in <a href="#RFC2119" id="rfc.xref.RFC2119.1"><cite title="Key words for use in RFCs to Indicate Requirement Levels">[RFC2119]</cite></a>.
676            </p>
677            <p id="rfc.section.1.1.p.2">This document defines conformance criteria for several roles in HTTP communication, including Senders, Recipients, Clients,
678               Servers, User-Agents, Origin Servers, Intermediaries, Proxies and Gateways. See <a href="p1-messaging.html#architecture" title="Architecture">Section 2</a> of <a href="#Part1" id="rfc.xref.Part1.1"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a> for definitions of these terms.
679            </p>
680            <p id="rfc.section.1.1.p.3">An implementation is considered conformant if it complies with all of the requirements associated with its role(s). Note that
681               SHOULD-level requirements are relevant here, unless one of the documented exceptions is applicable.
682            </p>
683            <p id="rfc.section.1.1.p.4">This document also uses ABNF to define valid protocol elements (<a href="#notation" title="Syntax Notation">Section&nbsp;1.2</a>). In addition to the prose requirements placed upon them, Senders <em class="bcp14">MUST NOT</em> generate protocol elements that are invalid.
684            </p>
685            <p id="rfc.section.1.1.p.5">Unless noted otherwise, Recipients <em class="bcp14">MAY</em> take steps to recover a usable protocol element from an invalid construct. However, HTTP does not define specific error handling
686               mechanisms, except in cases where it has direct impact on security. This is because different uses of the protocol require
687               different error handling strategies; for example, a Web browser may wish to transparently recover from a response where the
688               Location header field doesn't parse according to the ABNF, whereby in a systems control protocol using HTTP, this type of
689               error recovery could lead to dangerous consequences.
690            </p>
691         </div>
692         <div id="notation">
693            <h2 id="rfc.section.1.2"><a href="#rfc.section.1.2">1.2</a>&nbsp;<a href="#notation">Syntax Notation</a></h2>
694            <p id="rfc.section.1.2.p.1">This specification uses the Augmented Backus-Naur Form (ABNF) notation of <a href="#RFC5234" id="rfc.xref.RFC5234.1"><cite title="Augmented BNF for Syntax Specifications: ABNF">[RFC5234]</cite></a> with the list rule extension defined in <a href="p1-messaging.html#notation" title="Syntax Notation">Section 1.2</a> of <a href="#Part1" id="rfc.xref.Part1.2"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>. <a href="#collected.abnf" title="Collected ABNF">Appendix&nbsp;B</a> shows the collected ABNF with the list rule expanded.
695            </p>
696            <p id="rfc.section.1.2.p.2">The following core rules are included by reference, as defined in <a href="#RFC5234" id="rfc.xref.RFC5234.2"><cite title="Augmented BNF for Syntax Specifications: ABNF">[RFC5234]</cite></a>, <a href="https://tools.ietf.org/html/rfc5234#appendix-B.1">Appendix B.1</a>: ALPHA (letters), CR (carriage return), CRLF (CR LF), CTL (controls), DIGIT (decimal 0-9), DQUOTE (double quote), HEXDIG
697               (hexadecimal 0-9/A-F/a-f), LF (line feed), OCTET (any 8-bit sequence of data), SP (space), and VCHAR (any visible US-ASCII
698               character).
699            </p>
700            <div id="core.rules">
701               <h3 id="rfc.section.1.2.1"><a href="#rfc.section.1.2.1">1.2.1</a>&nbsp;<a href="#core.rules">Core Rules</a></h3>
702               <p id="rfc.section.1.2.1.p.1">The core rules below are defined in <a href="#Part1" id="rfc.xref.Part1.3"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>:
703               </p>
704               <div id="rfc.figure.u.1"></div><pre class="inline">  <a href="#core.rules" class="smpl">BWS</a>           = &lt;BWS, defined in <a href="#Part1" id="rfc.xref.Part1.4"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.1</a>&gt;
705  <a href="#core.rules" class="smpl">OWS</a>           = &lt;OWS, defined in <a href="#Part1" id="rfc.xref.Part1.5"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.1</a>&gt;
706  <a href="#core.rules" class="smpl">quoted-string</a> = &lt;quoted-string, defined in <a href="#Part1" id="rfc.xref.Part1.6"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a>&gt;
707  <a href="#core.rules" class="smpl">token</a>         = &lt;token, defined in <a href="#Part1" id="rfc.xref.Part1.7"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.4</a>&gt;
708</pre></div>
709         </div>
710      </div>
711      <div id="access.authentication.framework">
712         <h1 id="rfc.section.2"><a href="#rfc.section.2">2.</a>&nbsp;<a href="#access.authentication.framework">Access Authentication Framework</a></h1>
713         <div id="challenge.and.response">
714            <h2 id="rfc.section.2.1"><a href="#rfc.section.2.1">2.1</a>&nbsp;<a href="#challenge.and.response">Challenge and Response</a></h2>
715            <p id="rfc.section.2.1.p.1">HTTP provides a simple challenge-response authentication mechanism that can be used by a server to challenge a client request
716               and by a client to provide authentication information. It uses an extensible, case-insensitive token to identify the authentication
717               scheme, followed by additional information necessary for achieving authentication via that scheme. The latter can either be
718               a comma-separated list of parameters or a single sequence of characters capable of holding base64-encoded information.
719            </p>
720            <p id="rfc.section.2.1.p.2">Parameters are name-value pairs where the name is matched case-insensitively, and each parameter name <em class="bcp14">MUST</em> only occur once per challenge.
721            </p>
722            <div id="rfc.figure.u.2"></div><pre class="inline"><span id="rfc.iref.a.1"></span><span id="rfc.iref.a.2"></span><span id="rfc.iref.g.1"></span><span id="rfc.iref.g.2"></span><span id="rfc.iref.b.1"></span><span id="rfc.iref.g.3"></span>  auth-scheme    = <a href="#core.rules" class="smpl">token</a>
723 
724  auth-param     = <a href="#core.rules" class="smpl">token</a> <a href="#core.rules" class="smpl">BWS</a> "=" <a href="#core.rules" class="smpl">BWS</a> ( <a href="#core.rules" class="smpl">token</a> / <a href="#core.rules" class="smpl">quoted-string</a> )
725
726  b64token       = 1*( <a href="#notation" class="smpl">ALPHA</a> / <a href="#notation" class="smpl">DIGIT</a> /
727                       "-" / "." / "_" / "~" / "+" / "/" ) *"="
728</pre><p id="rfc.section.2.1.p.4">The "b64token" syntax allows the 66 unreserved URI characters (<a href="#RFC3986" id="rfc.xref.RFC3986.1"><cite title="Uniform Resource Identifier (URI): Generic Syntax">[RFC3986]</cite></a>), plus a few others, so that it can hold a base64, base64url (URL and filename safe alphabet), base32, or base16 (hex) encoding,
729               with or without padding, but excluding whitespace (<a href="#RFC4648" id="rfc.xref.RFC4648.1"><cite title="The Base16, Base32, and Base64 Data Encodings">[RFC4648]</cite></a>).
730            </p>
731            <p id="rfc.section.2.1.p.5">The 401 (Unauthorized) response message is used by an origin server to challenge the authorization of a user agent. This response <em class="bcp14">MUST</em> include a WWW-Authenticate header field containing at least one challenge applicable to the requested resource.
732            </p>
733            <p id="rfc.section.2.1.p.6">The 407 (Proxy Authentication Required) response message is used by a proxy to challenge the authorization of a client and <em class="bcp14">MUST</em> include a Proxy-Authenticate header field containing at least one challenge applicable to the proxy for the requested resource.
734            </p>
735            <div id="rfc.figure.u.3"></div><pre class="inline"><span id="rfc.iref.c.1"></span><span id="rfc.iref.g.4"></span>  <a href="#challenge.and.response" class="smpl">challenge</a>   = <a href="#challenge.and.response" class="smpl">auth-scheme</a> [ 1*<a href="#notation" class="smpl">SP</a> ( <a href="#challenge.and.response" class="smpl">b64token</a> / #<a href="#challenge.and.response" class="smpl">auth-param</a> ) ]
736</pre><div class="note" id="rfc.section.2.1.p.8">
737               <p><b>Note:</b> User agents will need to take special care in parsing the WWW-Authenticate and Proxy-Authenticate header field values because
738                  they can contain more than one challenge, or if more than one of each is provided, since the contents of a challenge can itself
739                  contain a comma-separated list of authentication parameters.
740               </p>
741            </div>
742            <div class="note" id="rfc.section.2.1.p.9">
743               <p><b>Note:</b> Many browsers fail to parse challenges containing unknown schemes. A workaround for this problem is to list well-supported
744                  schemes (such as "basic") first.
745               </p>
746            </div>
747            <p id="rfc.section.2.1.p.10">A user agent that wishes to authenticate itself with an origin server — usually, but not necessarily, after receiving a 401
748               (Unauthorized) — <em class="bcp14">MAY</em> do so by including an Authorization header field with the request.
749            </p>
750            <p id="rfc.section.2.1.p.11">A client that wishes to authenticate itself with a proxy — usually, but not necessarily, after receiving a 407 (Proxy Authentication
751               Required) — <em class="bcp14">MAY</em> do so by including a Proxy-Authorization header field with the request.
752            </p>
753            <p id="rfc.section.2.1.p.12">Both the Authorization field value and the Proxy-Authorization field value consist of credentials containing the authentication
754               information of the client for the realm of the resource being requested. The user agent <em class="bcp14">MUST</em> choose to use one of the challenges with the strongest auth-scheme it understands and request credentials from the user based
755               upon that challenge.
756            </p>
757            <div id="rfc.figure.u.4"></div><pre class="inline"><span id="rfc.iref.c.2"></span><span id="rfc.iref.g.5"></span>  <a href="#challenge.and.response" class="smpl">credentials</a> = <a href="#challenge.and.response" class="smpl">auth-scheme</a> [ 1*<a href="#notation" class="smpl">SP</a> ( <a href="#challenge.and.response" class="smpl">b64token</a> / #<a href="#challenge.and.response" class="smpl">auth-param</a> ) ]
758</pre><p id="rfc.section.2.1.p.14">If the origin server does not wish to accept the credentials sent with a request, it <em class="bcp14">SHOULD</em> return a 401 (Unauthorized) response. The response <em class="bcp14">MUST</em> include a WWW-Authenticate header field containing at least one (possibly new) challenge applicable to the requested resource.
759            </p>
760            <p id="rfc.section.2.1.p.15">If a proxy does not accept the credentials sent with a request, it <em class="bcp14">SHOULD</em> return a 407 (Proxy Authentication Required). The response <em class="bcp14">MUST</em> include a Proxy-Authenticate header field containing a (possibly new) challenge applicable to the proxy for the requested
761               resource.
762            </p>
763            <p id="rfc.section.2.1.p.16">The HTTP protocol does not restrict applications to this simple challenge-response mechanism for access authentication. Additional
764               mechanisms <em class="bcp14">MAY</em> be used, such as encryption at the transport level or via message encapsulation, and with additional header fields specifying
765               authentication information. However, such additional mechanisms are not defined by this specification.
766            </p>
767            <p id="rfc.section.2.1.p.17">Proxies <em class="bcp14">MUST</em> forward the WWW-Authenticate and Authorization headers unmodified and follow the rules found in <a href="#header.authorization" id="rfc.xref.header.authorization.1" title="Authorization">Section&nbsp;4.1</a>.
768            </p>
769         </div>
770         <div id="protection.space">
771            <div id="rfc.iref.p.1"></div>
772            <div id="rfc.iref.r.1"></div>
773            <h2 id="rfc.section.2.2"><a href="#rfc.section.2.2">2.2</a>&nbsp;<a href="#protection.space">Protection Space (Realm)</a></h2>
774            <p id="rfc.section.2.2.p.1">The authentication parameter realm is reserved for use by authentication schemes that wish to indicate the scope of protection.</p>
775            <p id="rfc.section.2.2.p.2">A <dfn>protection space</dfn> is defined by the canonical root URI (the scheme and authority components of the effective request URI; see <a href="p1-messaging.html#effective.request.uri" title="Effective Request URI">Section 5.5</a> of <a href="#Part1" id="rfc.xref.Part1.8"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>) of the server being accessed, in combination with the realm value if present. These realms allow the protected resources
776               on a server to be partitioned into a set of protection spaces, each with its own authentication scheme and/or authorization
777               database. The realm value is a string, generally assigned by the origin server, which can have additional semantics specific
778               to the authentication scheme. Note that there can be multiple challenges with the same auth-scheme but different realms.
779            </p>
780            <p id="rfc.section.2.2.p.3">The protection space determines the domain over which credentials can be automatically applied. If a prior request has been
781               authorized, the same credentials <em class="bcp14">MAY</em> be reused for all other requests within that protection space for a period of time determined by the authentication scheme,
782               parameters, and/or user preference. Unless otherwise defined by the authentication scheme, a single protection space cannot
783               extend outside the scope of its server.
784            </p>
785            <p id="rfc.section.2.2.p.4">For historical reasons, senders <em class="bcp14">MUST</em> only use the quoted-string syntax. Recipients might have to support both token and quoted-string syntax for maximum interoperability
786               with existing clients that have been accepting both notations for a long time.
787            </p>
788         </div>
789         <div id="authentication.scheme.registry">
790            <h2 id="rfc.section.2.3"><a href="#rfc.section.2.3">2.3</a>&nbsp;<a href="#authentication.scheme.registry">Authentication Scheme Registry</a></h2>
791            <p id="rfc.section.2.3.p.1">The HTTP Authentication Scheme Registry defines the name space for the authentication schemes in challenges and credentials.</p>
792            <p id="rfc.section.2.3.p.2">Registrations <em class="bcp14">MUST</em> include the following fields:
793            </p>
794            <ul>
795               <li>Authentication Scheme Name</li>
796               <li>Pointer to specification text</li>
797               <li>Notes (optional)</li>
798            </ul>
799            <p id="rfc.section.2.3.p.3">Values to be added to this name space require IETF Review (see <a href="#RFC5226" id="rfc.xref.RFC5226.1"><cite title="Guidelines for Writing an IANA Considerations Section in RFCs">[RFC5226]</cite></a>, <a href="https://tools.ietf.org/html/rfc5226#section-4.1">Section 4.1</a>).
800            </p>
801            <p id="rfc.section.2.3.p.4">The registry itself is maintained at &lt;<a href="http://www.iana.org/assignments/http-authschemes">http://www.iana.org/assignments/http-authschemes</a>&gt;.
802            </p>
803            <div id="considerations.for.new.authentication.schemes">
804               <h3 id="rfc.section.2.3.1"><a href="#rfc.section.2.3.1">2.3.1</a>&nbsp;<a href="#considerations.for.new.authentication.schemes">Considerations for New Authentication Schemes</a></h3>
805               <p id="rfc.section.2.3.1.p.1">There are certain aspects of the HTTP Authentication Framework that put constraints on how new authentication schemes can
806                  work:
807               </p>
808               <p id="rfc.section.2.3.1.p.2"></p>
809               <ul>
810                  <li>
811                     <p>HTTP authentication is presumed to be stateless: all of the information necessary to authenticate a request <em class="bcp14">MUST</em> be provided in the request, rather than be dependent on the server remembering prior requests. Authentication based on, or
812                        bound to, the underlying connection is outside the scope of this specification and inherently flawed unless steps are taken
813                        to ensure that the connection cannot be used by any party other than the authenticated user (see <a href="p1-messaging.html#intermediaries" title="Intermediaries">Section 2.3</a> of <a href="#Part1" id="rfc.xref.Part1.9"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
814                     </p>
815                  </li>
816                  <li>
817                     <p>The authentication parameter "realm" is reserved for defining Protection Spaces as defined in <a href="#protection.space" title="Protection Space (Realm)">Section&nbsp;2.2</a>. New schemes <em class="bcp14">MUST NOT</em> use it in a way incompatible with that definition.
818                     </p>
819                  </li>
820                  <li>
821                     <p>The "b64token" notation was introduced for compatibility with existing authentication schemes and can only be used once per
822                        challenge/credentials. New schemes thus ought to use the "auth-param" syntax instead, because otherwise future extensions
823                        will be impossible.
824                     </p>
825                  </li>
826                  <li>
827                     <p>The parsing of challenges and credentials is defined by this specification, and cannot be modified by new authentication schemes.
828                        When the auth-param syntax is used, all parameters ought to support both token and quoted-string syntax, and syntactical constraints
829                        ought to be defined on the field value after parsing (i.e., quoted-string processing). This is necessary so that recipients
830                        can use a generic parser that applies to all authentication schemes.
831                     </p>
832                     <p><b>Note:</b> the fact that the value syntax for the "realm" parameter is restricted to quoted-string was a bad design choice not to be
833                        repeated for new parameters.
834                     </p>
835                  </li>
836                  <li>
837                     <p>Definitions of new schemes ought to define the treatment of unknown extension parameters. In general, a "must-ignore" rule
838                        is preferable over "must-understand", because otherwise it will be hard to introduce new parameters in the presence of legacy
839                        recipients. Furthermore, it's good to describe the policy for defining new parameters (such as "update the specification",
840                        or "use this registry").
841                     </p>
842                  </li>
843                  <li>
844                     <p>Authentication schemes need to document whether they are usable in origin-server authentication (i.e., using WWW-Authenticate),
845                        and/or proxy authentication (i.e., using Proxy-Authenticate).
846                     </p>
847                  </li>
848                  <li>
849                     <p>The credentials carried in an Authorization header field are specific to the User Agent, and therefore have the same effect
850                        on HTTP caches as the "private" Cache-Control response directive, within the scope of the request they appear in.
851                     </p>
852                     <p>Therefore, new authentication schemes which choose not to carry credentials in the Authorization header (e.g., using a newly
853                        defined header) will need to explicitly disallow caching, by mandating the use of either Cache-Control request directives
854                        (e.g., "no-store") or response directives (e.g., "private").
855                     </p>
856                  </li>
857               </ul>
858            </div>
859         </div>
860      </div>
861      <div id="status.code.definitions">
862         <h1 id="rfc.section.3"><a href="#rfc.section.3">3.</a>&nbsp;<a href="#status.code.definitions">Status Code Definitions</a></h1>
863         <div id="status.401">
864            <div id="rfc.iref.4.1"></div>
865            <div id="rfc.iref.s.1"></div>
866            <h2 id="rfc.section.3.1"><a href="#rfc.section.3.1">3.1</a>&nbsp;<a href="#status.401">401 Unauthorized</a></h2>
867            <p id="rfc.section.3.1.p.1">The request requires user authentication. The response <em class="bcp14">MUST</em> include a WWW-Authenticate header field (<a href="#header.www-authenticate" id="rfc.xref.header.www-authenticate.1" title="WWW-Authenticate">Section&nbsp;4.4</a>) containing a challenge applicable to the target resource. The client <em class="bcp14">MAY</em> repeat the request with a suitable Authorization header field (<a href="#header.authorization" id="rfc.xref.header.authorization.2" title="Authorization">Section&nbsp;4.1</a>). If the request already included Authorization credentials, then the 401 response indicates that authorization has been
868               refused for those credentials. If the 401 response contains the same challenge as the prior response, and the user agent has
869               already attempted authentication at least once, then the user <em class="bcp14">SHOULD</em> be presented the representation that was given in the response, since that representation might include relevant diagnostic
870               information.
871            </p>
872         </div>
873         <div id="status.407">
874            <div id="rfc.iref.4.2"></div>
875            <div id="rfc.iref.s.2"></div>
876            <h2 id="rfc.section.3.2"><a href="#rfc.section.3.2">3.2</a>&nbsp;<a href="#status.407">407 Proxy Authentication Required</a></h2>
877            <p id="rfc.section.3.2.p.1">This code is similar to 401 (Unauthorized), but indicates that the client ought to first authenticate itself with the proxy.
878               The proxy <em class="bcp14">MUST</em> return a Proxy-Authenticate header field (<a href="#header.proxy-authenticate" id="rfc.xref.header.proxy-authenticate.1" title="Proxy-Authenticate">Section&nbsp;4.2</a>) containing a challenge applicable to the proxy for the target resource. The client <em class="bcp14">MAY</em> repeat the request with a suitable Proxy-Authorization header field (<a href="#header.proxy-authorization" id="rfc.xref.header.proxy-authorization.1" title="Proxy-Authorization">Section&nbsp;4.3</a>).
879            </p>
880         </div>
881      </div>
882      <div id="header.field.definitions">
883         <h1 id="rfc.section.4"><a href="#rfc.section.4">4.</a>&nbsp;<a href="#header.field.definitions">Header Field Definitions</a></h1>
884         <p id="rfc.section.4.p.1">This section defines the syntax and semantics of HTTP/1.1 header fields related to authentication.</p>
885         <div id="header.authorization">
886            <div id="rfc.iref.a.3"></div>
887            <div id="rfc.iref.h.1"></div>
888            <h2 id="rfc.section.4.1"><a href="#rfc.section.4.1">4.1</a>&nbsp;<a href="#header.authorization">Authorization</a></h2>
889            <p id="rfc.section.4.1.p.1">The "Authorization" header field allows a user agent to authenticate itself with a server — usually, but not necessarily,
890               after receiving a 401 (Unauthorized) response. Its value consists of credentials containing information of the user agent
891               for the realm of the resource being requested.
892            </p>
893            <div id="rfc.figure.u.5"></div><pre class="inline"><span id="rfc.iref.g.6"></span>  <a href="#header.authorization" class="smpl">Authorization</a> = <a href="#challenge.and.response" class="smpl">credentials</a>
894</pre><p id="rfc.section.4.1.p.3">If a request is authenticated and a realm specified, the same credentials <em class="bcp14">SHOULD</em> be valid for all other requests within this realm (assuming that the authentication scheme itself does not require otherwise,
895               such as credentials that vary according to a challenge value or using synchronized clocks).
896            </p>
897            <p id="rfc.section.4.1.p.4">When a shared cache (see <a href="p6-cache.html#shared.and.non-shared.caches">Section 1.2</a> of <a href="#Part6" id="rfc.xref.Part6.1"><cite title="HTTP/1.1, part 6: Caching">[Part6]</cite></a>) receives a request containing an Authorization field, it <em class="bcp14">MUST NOT</em> return the corresponding response as a reply to any other request, unless one of the following specific exceptions holds:
898            </p>
899            <p id="rfc.section.4.1.p.5"></p>
900            <ol>
901               <li>If the response includes the "s-maxage" cache-control directive, the cache <em class="bcp14">MAY</em> use that response in replying to a subsequent request. But (if the specified maximum age has passed) a proxy cache <em class="bcp14">MUST</em> first revalidate it with the origin server, using the header fields from the new request to allow the origin server to authenticate
902                  the new request. (This is the defined behavior for s-maxage.) If the response includes "s-maxage=0", the proxy <em class="bcp14">MUST</em> always revalidate it before re-using it.
903               </li>
904               <li>If the response includes the "must-revalidate" cache-control directive, the cache <em class="bcp14">MAY</em> use that response in replying to a subsequent request. But if the response is stale, all caches <em class="bcp14">MUST</em> first revalidate it with the origin server, using the header fields from the new request to allow the origin server to authenticate
905                  the new request.
906               </li>
907               <li>If the response includes the "public" cache-control directive, it <em class="bcp14">MAY</em> be returned in reply to any subsequent request.
908               </li>
909            </ol>
910         </div>
911         <div id="header.proxy-authenticate">
912            <div id="rfc.iref.p.2"></div>
913            <div id="rfc.iref.h.2"></div>
914            <h2 id="rfc.section.4.2"><a href="#rfc.section.4.2">4.2</a>&nbsp;<a href="#header.proxy-authenticate">Proxy-Authenticate</a></h2>
915            <p id="rfc.section.4.2.p.1">The "Proxy-Authenticate" header field consists of a challenge that indicates the authentication scheme and parameters applicable
916               to the proxy for this effective request URI (<a href="p1-messaging.html#effective.request.uri" title="Effective Request URI">Section 5.5</a> of <a href="#Part1" id="rfc.xref.Part1.10"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>). It <em class="bcp14">MUST</em> be included as part of a 407 (Proxy Authentication Required) response.
917            </p>
918            <div id="rfc.figure.u.6"></div><pre class="inline"><span id="rfc.iref.g.7"></span>  <a href="#header.proxy-authenticate" class="smpl">Proxy-Authenticate</a> = 1#<a href="#challenge.and.response" class="smpl">challenge</a>
919</pre><p id="rfc.section.4.2.p.3">Unlike WWW-Authenticate, the Proxy-Authenticate header field applies only to the current connection and <em class="bcp14">SHOULD NOT</em> be passed on to downstream clients. However, an intermediate proxy might need to obtain its own credentials by requesting
920               them from the downstream client, which in some circumstances will appear as if the proxy is forwarding the Proxy-Authenticate
921               header field.
922            </p>
923            <p id="rfc.section.4.2.p.4">Note that the parsing considerations for WWW-Authenticate apply to this header field as well; see <a href="#header.www-authenticate" id="rfc.xref.header.www-authenticate.2" title="WWW-Authenticate">Section&nbsp;4.4</a> for details.
924            </p>
925         </div>
926         <div id="header.proxy-authorization">
927            <div id="rfc.iref.p.3"></div>
928            <div id="rfc.iref.h.3"></div>
929            <h2 id="rfc.section.4.3"><a href="#rfc.section.4.3">4.3</a>&nbsp;<a href="#header.proxy-authorization">Proxy-Authorization</a></h2>
930            <p id="rfc.section.4.3.p.1">The "Proxy-Authorization" header field allows the client to identify itself (or its user) to a proxy which requires authentication.
931               Its value consists of credentials containing the authentication information of the user agent for the proxy and/or realm of
932               the resource being requested.
933            </p>
934            <div id="rfc.figure.u.7"></div><pre class="inline"><span id="rfc.iref.g.8"></span>  <a href="#header.proxy-authorization" class="smpl">Proxy-Authorization</a> = <a href="#challenge.and.response" class="smpl">credentials</a>
935</pre><p id="rfc.section.4.3.p.3">Unlike Authorization, the Proxy-Authorization header field applies only to the next outbound proxy that demanded authentication
936               using the Proxy-Authenticate field. When multiple proxies are used in a chain, the Proxy-Authorization header field is consumed
937               by the first outbound proxy that was expecting to receive credentials. A proxy <em class="bcp14">MAY</em> relay the credentials from the client request to the next proxy if that is the mechanism by which the proxies cooperatively
938               authenticate a given request.
939            </p>
940         </div>
941         <div id="header.www-authenticate">
942            <div id="rfc.iref.w.1"></div>
943            <div id="rfc.iref.h.4"></div>
944            <h2 id="rfc.section.4.4"><a href="#rfc.section.4.4">4.4</a>&nbsp;<a href="#header.www-authenticate">WWW-Authenticate</a></h2>
945            <p id="rfc.section.4.4.p.1">The "WWW-Authenticate" header field consists of at least one challenge that indicates the authentication scheme(s) and parameters
946               applicable to the effective request URI (<a href="p1-messaging.html#effective.request.uri" title="Effective Request URI">Section 5.5</a> of <a href="#Part1" id="rfc.xref.Part1.11"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a>).
947            </p>
948            <p id="rfc.section.4.4.p.2">It <em class="bcp14">MUST</em> be included in 401 (Unauthorized) response messages and <em class="bcp14">MAY</em> be included in other response messages to indicate that supplying credentials (or different credentials) might affect the
949               response.
950            </p>
951            <div id="rfc.figure.u.8"></div><pre class="inline"><span id="rfc.iref.g.9"></span>  <a href="#header.www-authenticate" class="smpl">WWW-Authenticate</a> = 1#<a href="#challenge.and.response" class="smpl">challenge</a>
952</pre><p id="rfc.section.4.4.p.4">User agents are advised to take special care in parsing the WWW-Authenticate field value as it might contain more than one
953               challenge, or if more than one WWW-Authenticate header field is provided, the contents of a challenge itself can contain a
954               comma-separated list of authentication parameters.
955            </p>
956            <div id="rfc.figure.u.9"></div>
957            <p>For instance:</p><pre class="text">  WWW-Authenticate: Newauth realm="apps", type=1,
958                    title="Login to \"apps\"", Basic realm="simple"
959</pre><p>This header field contains two challenges; one for the "Newauth" scheme with a realm value of "apps", and two additional parameters
960               "type" and "title", and another one for the "Basic" scheme with a realm value of "simple".
961            </p>
962            <div class="note" id="rfc.section.4.4.p.6">
963               <p><b>Note:</b> The challenge grammar production uses the list syntax as well. Therefore, a sequence of comma, whitespace, and comma can be
964                  considered both as applying to the preceding challenge, or to be an empty entry in the list of challenges. In practice, this
965                  ambiguity does not affect the semantics of the header field value and thus is harmless.
966               </p>
967            </div>
968         </div>
969      </div>
970      <div id="IANA.considerations">
971         <h1 id="rfc.section.5"><a href="#rfc.section.5">5.</a>&nbsp;<a href="#IANA.considerations">IANA Considerations</a></h1>
972         <div id="authentication.scheme.registration">
973            <h2 id="rfc.section.5.1"><a href="#rfc.section.5.1">5.1</a>&nbsp;<a href="#authentication.scheme.registration">Authenticaton Scheme Registry</a></h2>
974            <p id="rfc.section.5.1.p.1">The registration procedure for HTTP Authentication Schemes is defined by <a href="#authentication.scheme.registry" title="Authentication Scheme Registry">Section&nbsp;2.3</a> of this document.
975            </p>
976            <p id="rfc.section.5.1.p.2">The HTTP Method Authentication Scheme shall be created at &lt;<a href="http://www.iana.org/assignments/http-authschemes">http://www.iana.org/assignments/http-authschemes</a>&gt;.
977            </p>
978         </div>
979         <div id="status.code.registration">
980            <h2 id="rfc.section.5.2"><a href="#rfc.section.5.2">5.2</a>&nbsp;<a href="#status.code.registration">Status Code Registration</a></h2>
981            <p id="rfc.section.5.2.p.1">The HTTP Status Code Registry located at &lt;<a href="http://www.iana.org/assignments/http-status-codes">http://www.iana.org/assignments/http-status-codes</a>&gt; shall be updated with the registrations below:
982            </p>
983            <div id="rfc.table.1">
984               <div id="iana.status.code.registration.table"></div>
985               <table class="tt full left" cellpadding="3" cellspacing="0">
986                  <thead>
987                     <tr>
988                        <th>Value</th>
989                        <th>Description</th>
990                        <th>Reference</th>
991                     </tr>
992                  </thead>
993                  <tbody>
994                     <tr>
995                        <td class="left">401</td>
996                        <td class="left">Unauthorized</td>
997                        <td class="left"><a href="#status.401" id="rfc.xref.status.401.1" title="401 Unauthorized">Section&nbsp;3.1</a>
998                        </td>
999                     </tr>
1000                     <tr>
1001                        <td class="left">407</td>
1002                        <td class="left">Proxy Authentication Required</td>
1003                        <td class="left"><a href="#status.407" id="rfc.xref.status.407.1" title="407 Proxy Authentication Required">Section&nbsp;3.2</a>
1004                        </td>
1005                     </tr>
1006                  </tbody>
1007               </table>
1008            </div>
1009         </div>
1010         <div id="header.field.registration">
1011            <h2 id="rfc.section.5.3"><a href="#rfc.section.5.3">5.3</a>&nbsp;<a href="#header.field.registration">Header Field Registration</a></h2>
1012            <p id="rfc.section.5.3.p.1">The Message Header Field Registry located at &lt;<a href="http://www.iana.org/assignments/message-headers/message-header-index.html">http://www.iana.org/assignments/message-headers/message-header-index.html</a>&gt; shall be updated with the permanent registrations below (see <a href="#RFC3864" id="rfc.xref.RFC3864.1"><cite title="Registration Procedures for Message Header Fields">[RFC3864]</cite></a>):
1013            </p>
1014            <div id="rfc.table.2">
1015               <div id="iana.header.registration.table"></div>
1016               <table class="tt full left" cellpadding="3" cellspacing="0">
1017                  <thead>
1018                     <tr>
1019                        <th>Header Field Name</th>
1020                        <th>Protocol</th>
1021                        <th>Status</th>
1022                        <th>Reference</th>
1023                     </tr>
1024                  </thead>
1025                  <tbody>
1026                     <tr>
1027                        <td class="left">Authorization</td>
1028                        <td class="left">http</td>
1029                        <td class="left">standard</td>
1030                        <td class="left"><a href="#header.authorization" id="rfc.xref.header.authorization.3" title="Authorization">Section&nbsp;4.1</a>
1031                        </td>
1032                     </tr>
1033                     <tr>
1034                        <td class="left">Proxy-Authenticate</td>
1035                        <td class="left">http</td>
1036                        <td class="left">standard</td>
1037                        <td class="left"><a href="#header.proxy-authenticate" id="rfc.xref.header.proxy-authenticate.2" title="Proxy-Authenticate">Section&nbsp;4.2</a>
1038                        </td>
1039                     </tr>
1040                     <tr>
1041                        <td class="left">Proxy-Authorization</td>
1042                        <td class="left">http</td>
1043                        <td class="left">standard</td>
1044                        <td class="left"><a href="#header.proxy-authorization" id="rfc.xref.header.proxy-authorization.2" title="Proxy-Authorization">Section&nbsp;4.3</a>
1045                        </td>
1046                     </tr>
1047                     <tr>
1048                        <td class="left">WWW-Authenticate</td>
1049                        <td class="left">http</td>
1050                        <td class="left">standard</td>
1051                        <td class="left"><a href="#header.www-authenticate" id="rfc.xref.header.www-authenticate.3" title="WWW-Authenticate">Section&nbsp;4.4</a>
1052                        </td>
1053                     </tr>
1054                  </tbody>
1055               </table>
1056            </div>
1057            <p id="rfc.section.5.3.p.2">The change controller is: "IETF (iesg@ietf.org) - Internet Engineering Task Force".</p>
1058         </div>
1059      </div>
1060      <div id="security.considerations">
1061         <h1 id="rfc.section.6"><a href="#rfc.section.6">6.</a>&nbsp;<a href="#security.considerations">Security Considerations</a></h1>
1062         <p id="rfc.section.6.p.1">This section is meant to inform application developers, information providers, and users of the security limitations in HTTP/1.1
1063            as described by this document. The discussion does not include definitive solutions to the problems revealed, though it does
1064            make some suggestions for reducing security risks.
1065         </p>
1066         <div id="auth.credentials.and.idle.clients">
1067            <h2 id="rfc.section.6.1"><a href="#rfc.section.6.1">6.1</a>&nbsp;<a href="#auth.credentials.and.idle.clients">Authentication Credentials and Idle Clients</a></h2>
1068            <p id="rfc.section.6.1.p.1">Existing HTTP clients and user agents typically retain authentication information indefinitely. HTTP/1.1 does not provide
1069               a method for a server to direct clients to discard these cached credentials. This is a significant defect that requires further
1070               extensions to HTTP. Circumstances under which credential caching can interfere with the application's security model include
1071               but are not limited to:
1072            </p>
1073            <ul>
1074               <li>Clients which have been idle for an extended period following which the server might wish to cause the client to reprompt
1075                  the user for credentials.
1076               </li>
1077               <li>Applications which include a session termination indication (such as a "logout" or "commit" button on a page) after which
1078                  the server side of the application "knows" that there is no further reason for the client to retain the credentials.
1079               </li>
1080            </ul>
1081            <p id="rfc.section.6.1.p.2">This is currently under separate study. There are a number of work-arounds to parts of this problem, and we encourage the
1082               use of password protection in screen savers, idle time-outs, and other methods which mitigate the security problems inherent
1083               in this problem. In particular, user agents which cache credentials are encouraged to provide a readily accessible mechanism
1084               for discarding cached credentials under user control.
1085            </p>
1086         </div>
1087      </div>
1088      <div id="acks">
1089         <h1 id="rfc.section.7"><a href="#rfc.section.7">7.</a>&nbsp;<a href="#acks">Acknowledgments</a></h1>
1090         <p id="rfc.section.7.p.1">This specification takes over the definition of the HTTP Authentication Framework, previously defined in <cite title="HTTP Authentication: Basic and Digest Access Authentication" id="rfc.xref.RFC2617.3">RFC 2617</cite>. We thank John Franks, Phillip M. Hallam-Baker, Jeffery L. Hostetler, Scott D. Lawrence, Paul J. Leach, Ari Luotonen, and
1091            Lawrence C. Stewart for their work on that specification. See <a href="https://tools.ietf.org/html/rfc2617#section-6">Section 6</a> of <a href="#RFC2617" id="rfc.xref.RFC2617.4"><cite title="HTTP Authentication: Basic and Digest Access Authentication">[RFC2617]</cite></a> for further acknowledgements.
1092         </p>
1093         <p id="rfc.section.7.p.2">See <a href="p1-messaging.html#acks" title="Acknowledgments">Section 9</a> of <a href="#Part1" id="rfc.xref.Part1.12"><cite title="HTTP/1.1, part 1: URIs, Connections, and Message Parsing">[Part1]</cite></a> for the Acknowledgments related to this document revision.
1094         </p>
1095      </div>
1096      <h1 id="rfc.references"><a id="rfc.section.8" href="#rfc.section.8">8.</a> References
1097      </h1>
1098      <h2 id="rfc.references.1"><a href="#rfc.section.8.1" id="rfc.section.8.1">8.1</a> Normative References
1099      </h2>
1100      <table>
1101         <tr>
1102            <td class="reference"><b id="Part1">[Part1]</b></td>
1103            <td class="top"><a href="mailto:fielding@gbiv.com" title="Adobe Systems Incorporated">Fielding, R., Ed.</a>, <a href="mailto:ylafon@w3.org" title="World Wide Web Consortium">Lafon, Y., Ed.</a>, and <a href="mailto:julian.reschke@greenbytes.de" title="greenbytes GmbH">J. Reschke, Ed.</a>, “<a href="https://tools.ietf.org/html/draft-ietf-httpbis-p1-messaging-19">HTTP/1.1, part 1: URIs, Connections, and Message Parsing</a>”, Internet-Draft&nbsp;draft-ietf-httpbis-p1-messaging-19 (work in progress), March&nbsp;2012.
1104            </td>
1105         </tr>
1106         <tr>
1107            <td class="reference"><b id="Part6">[Part6]</b></td>
1108            <td class="top"><a href="mailto:fielding@gbiv.com" title="Adobe Systems Incorporated">Fielding, R., Ed.</a>, <a href="mailto:ylafon@w3.org" title="World Wide Web Consortium">Lafon, Y., Ed.</a>, <a href="mailto:mnot@mnot.net" title="Rackspace">Nottingham, M., Ed.</a>, and <a href="mailto:julian.reschke@greenbytes.de" title="greenbytes GmbH">J. Reschke, Ed.</a>, “<a href="https://tools.ietf.org/html/draft-ietf-httpbis-p6-cache-19">HTTP/1.1, part 6: Caching</a>”, Internet-Draft&nbsp;draft-ietf-httpbis-p6-cache-19 (work in progress), March&nbsp;2012.
1109            </td>
1110         </tr>
1111         <tr>
1112            <td class="reference"><b id="RFC2119">[RFC2119]</b></td>
1113            <td class="top"><a href="mailto:sob@harvard.edu" title="Harvard University">Bradner, S.</a>, “<a href="https://tools.ietf.org/html/rfc2119">Key words for use in RFCs to Indicate Requirement Levels</a>”, BCP&nbsp;14, RFC&nbsp;2119, March&nbsp;1997.
1114            </td>
1115         </tr>
1116         <tr>
1117            <td class="reference"><b id="RFC5234">[RFC5234]</b></td>
1118            <td class="top"><a href="mailto:dcrocker@bbiw.net" title="Brandenburg InternetWorking">Crocker, D., Ed.</a> and <a href="mailto:paul.overell@thus.net" title="THUS plc.">P. Overell</a>, “<a href="https://tools.ietf.org/html/rfc5234">Augmented BNF for Syntax Specifications: ABNF</a>”, STD&nbsp;68, RFC&nbsp;5234, January&nbsp;2008.
1119            </td>
1120         </tr>
1121      </table>
1122      <h2 id="rfc.references.2"><a href="#rfc.section.8.2" id="rfc.section.8.2">8.2</a> Informative References
1123      </h2>
1124      <table>
1125         <tr>
1126            <td class="reference"><b id="RFC2616">[RFC2616]</b></td>
1127            <td class="top"><a href="mailto:fielding@ics.uci.edu" title="University of California, Irvine">Fielding, R.</a>, <a href="mailto:jg@w3.org" title="W3C">Gettys, J.</a>, <a href="mailto:mogul@wrl.dec.com" title="Compaq Computer Corporation">Mogul, J.</a>, <a href="mailto:frystyk@w3.org" title="MIT Laboratory for Computer Science">Frystyk, H.</a>, <a href="mailto:masinter@parc.xerox.com" title="Xerox Corporation">Masinter, L.</a>, <a href="mailto:paulle@microsoft.com" title="Microsoft Corporation">Leach, P.</a>, and <a href="mailto:timbl@w3.org" title="W3C">T. Berners-Lee</a>, “<a href="https://tools.ietf.org/html/rfc2616">Hypertext Transfer Protocol -- HTTP/1.1</a>”, RFC&nbsp;2616, June&nbsp;1999.
1128            </td>
1129         </tr>
1130         <tr>
1131            <td class="reference"><b id="RFC2617">[RFC2617]</b></td>
1132            <td class="top"><a href="mailto:john@math.nwu.edu" title="Northwestern University, Department of Mathematics">Franks, J.</a>, <a href="mailto:pbaker@verisign.com" title="Verisign Inc.">Hallam-Baker, P.</a>, <a href="mailto:jeff@AbiSource.com" title="AbiSource, Inc.">Hostetler, J.</a>, <a href="mailto:lawrence@agranat.com" title="Agranat Systems, Inc.">Lawrence, S.</a>, <a href="mailto:paulle@microsoft.com" title="Microsoft Corporation">Leach, P.</a>, Luotonen, A., and <a href="mailto:stewart@OpenMarket.com" title="Open Market, Inc.">L. Stewart</a>, “<a href="https://tools.ietf.org/html/rfc2617">HTTP Authentication: Basic and Digest Access Authentication</a>”, RFC&nbsp;2617, June&nbsp;1999.
1133            </td>
1134         </tr>
1135         <tr>
1136            <td class="reference"><b id="RFC3864">[RFC3864]</b></td>
1137            <td class="top"><a href="mailto:GK-IETF@ninebynine.org" title="Nine by Nine">Klyne, G.</a>, <a href="mailto:mnot@pobox.com" title="BEA Systems">Nottingham, M.</a>, and <a href="mailto:JeffMogul@acm.org" title="HP Labs">J. Mogul</a>, “<a href="https://tools.ietf.org/html/rfc3864">Registration Procedures for Message Header Fields</a>”, BCP&nbsp;90, RFC&nbsp;3864, September&nbsp;2004.
1138            </td>
1139         </tr>
1140         <tr>
1141            <td class="reference"><b id="RFC3986">[RFC3986]</b></td>
1142            <td class="top"><a href="mailto:timbl@w3.org" title="World Wide Web Consortium">Berners-Lee, T.</a>, <a href="mailto:fielding@gbiv.com" title="Day Software">Fielding, R.</a>, and <a href="mailto:LMM@acm.org" title="Adobe Systems Incorporated">L. Masinter</a>, “<a href="https://tools.ietf.org/html/rfc3986">Uniform Resource Identifier (URI): Generic Syntax</a>”, STD&nbsp;66, RFC&nbsp;3986, January&nbsp;2005.
1143            </td>
1144         </tr>
1145         <tr>
1146            <td class="reference"><b id="RFC4648">[RFC4648]</b></td>
1147            <td class="top">Josefsson, S., “<a href="https://tools.ietf.org/html/rfc4648">The Base16, Base32, and Base64 Data Encodings</a>”, RFC&nbsp;4648, October&nbsp;2006.
1148            </td>
1149         </tr>
1150         <tr>
1151            <td class="reference"><b id="RFC5226">[RFC5226]</b></td>
1152            <td class="top"><a href="mailto:narten@us.ibm.com" title="IBM">Narten, T.</a> and <a href="mailto:Harald@Alvestrand.no" title="Google">H. Alvestrand</a>, “<a href="https://tools.ietf.org/html/rfc5226">Guidelines for Writing an IANA Considerations Section in RFCs</a>”, BCP&nbsp;26, RFC&nbsp;5226, May&nbsp;2008.
1153            </td>
1154         </tr>
1155      </table>
1156      <div id="changes.from.rfc.2616">
1157         <h1 id="rfc.section.A" class="np"><a href="#rfc.section.A">A.</a>&nbsp;<a href="#changes.from.rfc.2616">Changes from RFCs 2616 and 2617</a></h1>
1158         <p id="rfc.section.A.p.1">The "realm" parameter isn't required anymore in general; consequently, the ABNF allows challenges without any auth parameters.
1159            (<a href="#access.authentication.framework" title="Access Authentication Framework">Section&nbsp;2</a>)
1160         </p>
1161         <p id="rfc.section.A.p.2">The "b64token" alternative to auth-param lists has been added for consistency with legacy authentication schemes such as "Basic".
1162            (<a href="#access.authentication.framework" title="Access Authentication Framework">Section&nbsp;2</a>)
1163         </p>
1164         <p id="rfc.section.A.p.3">Change ABNF productions for header fields to only define the field value. (<a href="#header.field.definitions" title="Header Field Definitions">Section&nbsp;4</a>)
1165         </p>
1166      </div>
1167      <div id="collected.abnf">
1168         <h1 id="rfc.section.B"><a href="#rfc.section.B">B.</a>&nbsp;<a href="#collected.abnf">Collected ABNF</a></h1>
1169         <div id="rfc.figure.u.10"></div><pre class="inline"><a href="#header.authorization" class="smpl">Authorization</a> = credentials
1170
1171<a href="#core.rules" class="smpl">BWS</a> = &lt;BWS, defined in [Part1], Section 3.2.1&gt;
1172
1173<a href="#core.rules" class="smpl">OWS</a> = &lt;OWS, defined in [Part1], Section 3.2.1&gt;
1174
1175<a href="#header.proxy-authenticate" class="smpl">Proxy-Authenticate</a> = *( "," OWS ) challenge *( OWS "," [ OWS
1176 challenge ] )
1177<a href="#header.proxy-authorization" class="smpl">Proxy-Authorization</a> = credentials
1178
1179<a href="#header.www-authenticate" class="smpl">WWW-Authenticate</a> = *( "," OWS ) challenge *( OWS "," [ OWS challenge
1180 ] )
1181
1182<a href="#challenge.and.response" class="smpl">auth-param</a> = token BWS "=" BWS ( token / quoted-string )
1183<a href="#challenge.and.response" class="smpl">auth-scheme</a> = token
1184
1185<a href="#challenge.and.response" class="smpl">b64token</a> = 1*( ALPHA / DIGIT / "-" / "." / "_" / "~" / "+" / "/" )
1186 *"="
1187
1188<a href="#challenge.and.response" class="smpl">challenge</a> = auth-scheme [ 1*SP ( b64token / [ ( "," / auth-param ) *(
1189 OWS "," [ OWS auth-param ] ) ] ) ]
1190<a href="#challenge.and.response" class="smpl">credentials</a> = auth-scheme [ 1*SP ( b64token / [ ( "," / auth-param )
1191 *( OWS "," [ OWS auth-param ] ) ] ) ]
1192
1193<a href="#core.rules" class="smpl">quoted-string</a> = &lt;quoted-string, defined in [Part1], Section 3.2.4&gt;
1194
1195<a href="#core.rules" class="smpl">token</a> = &lt;token, defined in [Part1], Section 3.2.4&gt;
1196</pre><div id="rfc.figure.u.11"></div>
1197         <p>ABNF diagnostics:</p><pre class="inline">; Authorization defined but not used
1198; Proxy-Authenticate defined but not used
1199; Proxy-Authorization defined but not used
1200; WWW-Authenticate defined but not used
1201</pre></div>
1202      <div id="change.log">
1203         <h1 id="rfc.section.C"><a href="#rfc.section.C">C.</a>&nbsp;<a href="#change.log">Change Log (to be removed by RFC Editor before publication)</a></h1>
1204         <div>
1205            <h2 id="rfc.section.C.1"><a href="#rfc.section.C.1">C.1</a>&nbsp;Since RFC 2616
1206            </h2>
1207            <p id="rfc.section.C.1.p.1">Extracted relevant partitions from <a href="#RFC2616" id="rfc.xref.RFC2616.2"><cite title="Hypertext Transfer Protocol -- HTTP/1.1">[RFC2616]</cite></a>.
1208            </p>
1209         </div>
1210         <div>
1211            <h2 id="rfc.section.C.2"><a href="#rfc.section.C.2">C.2</a>&nbsp;Since draft-ietf-httpbis-p7-auth-00
1212            </h2>
1213            <p id="rfc.section.C.2.p.1">Closed issues: </p>
1214            <ul>
1215               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/35">http://tools.ietf.org/wg/httpbis/trac/ticket/35</a>&gt;: "Normative and Informative references"
1216               </li>
1217            </ul>
1218         </div>
1219         <div>
1220            <h2 id="rfc.section.C.3"><a href="#rfc.section.C.3">C.3</a>&nbsp;Since draft-ietf-httpbis-p7-auth-01
1221            </h2>
1222            <p id="rfc.section.C.3.p.1">Ongoing work on ABNF conversion (&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/36">http://tools.ietf.org/wg/httpbis/trac/ticket/36</a>&gt;):
1223            </p>
1224            <ul>
1225               <li>Explicitly import BNF rules for "challenge" and "credentials" from RFC2617.</li>
1226               <li>Add explicit references to BNF syntax and rules imported from other parts of the specification.</li>
1227            </ul>
1228         </div>
1229         <div id="changes.since.02">
1230            <h2 id="rfc.section.C.4"><a href="#rfc.section.C.4">C.4</a>&nbsp;<a href="#changes.since.02">Since draft-ietf-httpbis-p7-auth-02</a></h2>
1231            <p id="rfc.section.C.4.p.1">Ongoing work on IANA Message Header Field Registration (&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/40">http://tools.ietf.org/wg/httpbis/trac/ticket/40</a>&gt;):
1232            </p>
1233            <ul>
1234               <li>Reference RFC 3984, and update header field registrations for header fields defined in this document.</li>
1235            </ul>
1236         </div>
1237         <div id="changes.since.03">
1238            <h2 id="rfc.section.C.5"><a href="#rfc.section.C.5">C.5</a>&nbsp;<a href="#changes.since.03">Since draft-ietf-httpbis-p7-auth-03</a></h2>
1239            <p id="rfc.section.C.5.p.1">None.</p>
1240         </div>
1241         <div id="changes.since.04">
1242            <h2 id="rfc.section.C.6"><a href="#rfc.section.C.6">C.6</a>&nbsp;<a href="#changes.since.04">Since draft-ietf-httpbis-p7-auth-04</a></h2>
1243            <p id="rfc.section.C.6.p.1">Ongoing work on ABNF conversion (&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/36">http://tools.ietf.org/wg/httpbis/trac/ticket/36</a>&gt;):
1244            </p>
1245            <ul>
1246               <li>Use "/" instead of "|" for alternatives.</li>
1247               <li>Introduce new ABNF rules for "bad" whitespace ("BWS"), optional whitespace ("OWS") and required whitespace ("RWS").</li>
1248               <li>Rewrite ABNFs to spell out whitespace rules, factor out header field value format definitions.</li>
1249            </ul>
1250         </div>
1251         <div id="changes.since.05">
1252            <h2 id="rfc.section.C.7"><a href="#rfc.section.C.7">C.7</a>&nbsp;<a href="#changes.since.05">Since draft-ietf-httpbis-p7-auth-05</a></h2>
1253            <p id="rfc.section.C.7.p.1">Final work on ABNF conversion (&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/36">http://tools.ietf.org/wg/httpbis/trac/ticket/36</a>&gt;):
1254            </p>
1255            <ul>
1256               <li>Add appendix containing collected and expanded ABNF, reorganize ABNF introduction.</li>
1257            </ul>
1258         </div>
1259         <div id="changes.since.06">
1260            <h2 id="rfc.section.C.8"><a href="#rfc.section.C.8">C.8</a>&nbsp;<a href="#changes.since.06">Since draft-ietf-httpbis-p7-auth-06</a></h2>
1261            <p id="rfc.section.C.8.p.1">None.</p>
1262         </div>
1263         <div id="changes.since.07">
1264            <h2 id="rfc.section.C.9"><a href="#rfc.section.C.9">C.9</a>&nbsp;<a href="#changes.since.07">Since draft-ietf-httpbis-p7-auth-07</a></h2>
1265            <p id="rfc.section.C.9.p.1">Closed issues: </p>
1266            <ul>
1267               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/198">http://tools.ietf.org/wg/httpbis/trac/ticket/198</a>&gt;: "move IANA registrations for optional status codes"
1268               </li>
1269            </ul>
1270         </div>
1271         <div id="changes.since.08">
1272            <h2 id="rfc.section.C.10"><a href="#rfc.section.C.10">C.10</a>&nbsp;<a href="#changes.since.08">Since draft-ietf-httpbis-p7-auth-08</a></h2>
1273            <p id="rfc.section.C.10.p.1">No significant changes.</p>
1274         </div>
1275         <div id="changes.since.09">
1276            <h2 id="rfc.section.C.11"><a href="#rfc.section.C.11">C.11</a>&nbsp;<a href="#changes.since.09">Since draft-ietf-httpbis-p7-auth-09</a></h2>
1277            <p id="rfc.section.C.11.p.1">Partly resolved issues: </p>
1278            <ul>
1279               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/196">http://tools.ietf.org/wg/httpbis/trac/ticket/196</a>&gt;: "Term for the requested resource's URI"
1280               </li>
1281            </ul>
1282         </div>
1283         <div id="changes.since.10">
1284            <h2 id="rfc.section.C.12"><a href="#rfc.section.C.12">C.12</a>&nbsp;<a href="#changes.since.10">Since draft-ietf-httpbis-p7-auth-10</a></h2>
1285            <p id="rfc.section.C.12.p.1">None.</p>
1286         </div>
1287         <div id="changes.since.11">
1288            <h2 id="rfc.section.C.13"><a href="#rfc.section.C.13">C.13</a>&nbsp;<a href="#changes.since.11">Since draft-ietf-httpbis-p7-auth-11</a></h2>
1289            <p id="rfc.section.C.13.p.1">Closed issues: </p>
1290            <ul>
1291               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/130">http://tools.ietf.org/wg/httpbis/trac/ticket/130</a>&gt;: "introduction to part 7 is work-in-progress"
1292               </li>
1293               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/195">http://tools.ietf.org/wg/httpbis/trac/ticket/195</a>&gt;: "auth-param syntax"
1294               </li>
1295               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/224">http://tools.ietf.org/wg/httpbis/trac/ticket/224</a>&gt;: "Header Classification"
1296               </li>
1297               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/237">http://tools.ietf.org/wg/httpbis/trac/ticket/237</a>&gt;: "absorbing the auth framework from 2617"
1298               </li>
1299            </ul>
1300            <p id="rfc.section.C.13.p.2">Partly resolved issues: </p>
1301            <ul>
1302               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/141">http://tools.ietf.org/wg/httpbis/trac/ticket/141</a>&gt;: "should we have an auth scheme registry"
1303               </li>
1304            </ul>
1305         </div>
1306         <div id="changes.since.12">
1307            <h2 id="rfc.section.C.14"><a href="#rfc.section.C.14">C.14</a>&nbsp;<a href="#changes.since.12">Since draft-ietf-httpbis-p7-auth-12</a></h2>
1308            <p id="rfc.section.C.14.p.1">None.</p>
1309         </div>
1310         <div id="changes.since.13">
1311            <h2 id="rfc.section.C.15"><a href="#rfc.section.C.15">C.15</a>&nbsp;<a href="#changes.since.13">Since draft-ietf-httpbis-p7-auth-13</a></h2>
1312            <p id="rfc.section.C.15.p.1">Closed issues: </p>
1313            <ul>
1314               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/276">http://tools.ietf.org/wg/httpbis/trac/ticket/276</a>&gt;: "untangle ABNFs for header fields"
1315               </li>
1316            </ul>
1317         </div>
1318         <div id="changes.since.14">
1319            <h2 id="rfc.section.C.16"><a href="#rfc.section.C.16">C.16</a>&nbsp;<a href="#changes.since.14">Since draft-ietf-httpbis-p7-auth-14</a></h2>
1320            <p id="rfc.section.C.16.p.1">None.</p>
1321         </div>
1322         <div id="changes.since.15">
1323            <h2 id="rfc.section.C.17"><a href="#rfc.section.C.17">C.17</a>&nbsp;<a href="#changes.since.15">Since draft-ietf-httpbis-p7-auth-15</a></h2>
1324            <p id="rfc.section.C.17.p.1">Closed issues: </p>
1325            <ul>
1326               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/78">http://tools.ietf.org/wg/httpbis/trac/ticket/78</a>&gt;: "Relationship between 401, Authorization and WWW-Authenticate"
1327               </li>
1328               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/177">http://tools.ietf.org/wg/httpbis/trac/ticket/177</a>&gt;: "Realm required on challenges"
1329               </li>
1330               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/195">http://tools.ietf.org/wg/httpbis/trac/ticket/195</a>&gt;: "auth-param syntax"
1331               </li>
1332               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/257">http://tools.ietf.org/wg/httpbis/trac/ticket/257</a>&gt;: "Considerations for new authentications schemes"
1333               </li>
1334               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/287">http://tools.ietf.org/wg/httpbis/trac/ticket/287</a>&gt;: "LWS in auth-param ABNF"
1335               </li>
1336               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/309">http://tools.ietf.org/wg/httpbis/trac/ticket/309</a>&gt;: "credentials ABNF missing SP (still using implied LWS?)"
1337               </li>
1338            </ul>
1339         </div>
1340         <div id="changes.since.16">
1341            <h2 id="rfc.section.C.18"><a href="#rfc.section.C.18">C.18</a>&nbsp;<a href="#changes.since.16">Since draft-ietf-httpbis-p7-auth-16</a></h2>
1342            <p id="rfc.section.C.18.p.1">Closed issues: </p>
1343            <ul>
1344               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/186">http://tools.ietf.org/wg/httpbis/trac/ticket/186</a>&gt;: "Document HTTP's error-handling philosophy"
1345               </li>
1346               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/320">http://tools.ietf.org/wg/httpbis/trac/ticket/320</a>&gt;: "add advice on defining auth scheme parameters"
1347               </li>
1348            </ul>
1349         </div>
1350         <div id="changes.since.17">
1351            <h2 id="rfc.section.C.19"><a href="#rfc.section.C.19">C.19</a>&nbsp;<a href="#changes.since.17">Since draft-ietf-httpbis-p7-auth-17</a></h2>
1352            <p id="rfc.section.C.19.p.1">Closed issues: </p>
1353            <ul>
1354               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/314">http://tools.ietf.org/wg/httpbis/trac/ticket/314</a>&gt;: "allow unquoted realm parameters"
1355               </li>
1356               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/321">http://tools.ietf.org/wg/httpbis/trac/ticket/321</a>&gt;: "Repeating auth-params"
1357               </li>
1358            </ul>
1359         </div>
1360         <div id="changes.since.18">
1361            <h2 id="rfc.section.C.20"><a href="#rfc.section.C.20">C.20</a>&nbsp;<a href="#changes.since.18">Since draft-ietf-httpbis-p7-auth-18</a></h2>
1362            <p id="rfc.section.C.20.p.1">Closed issues: </p>
1363            <ul>
1364               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/334">http://tools.ietf.org/wg/httpbis/trac/ticket/334</a>&gt;: "recipient behavior for new auth parameters"
1365               </li>
1366               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/342">http://tools.ietf.org/wg/httpbis/trac/ticket/342</a>&gt;: "WWW-Authenticate ABNF slightly ambiguous"
1367               </li>
1368            </ul>
1369         </div>
1370      </div>
1371      <h1 id="rfc.index"><a href="#rfc.index">Index</a></h1>
1372      <p class="noprint"><a href="#rfc.index.4">4</a> <a href="#rfc.index.A">A</a> <a href="#rfc.index.B">B</a> <a href="#rfc.index.C">C</a> <a href="#rfc.index.G">G</a> <a href="#rfc.index.H">H</a> <a href="#rfc.index.P">P</a> <a href="#rfc.index.R">R</a> <a href="#rfc.index.S">S</a> <a href="#rfc.index.W">W</a>
1373      </p>
1374      <div class="print2col">
1375         <ul class="ind">
1376            <li><a id="rfc.index.4" href="#rfc.index.4"><b>4</b></a><ul>
1377                  <li>401 Unauthorized (status code)&nbsp;&nbsp;<a href="#rfc.iref.4.1"><b>3.1</b></a>, <a href="#rfc.xref.status.401.1">5.2</a></li>
1378                  <li>407 Proxy Authentication Required (status code)&nbsp;&nbsp;<a href="#rfc.iref.4.2"><b>3.2</b></a>, <a href="#rfc.xref.status.407.1">5.2</a></li>
1379               </ul>
1380            </li>
1381            <li><a id="rfc.index.A" href="#rfc.index.A"><b>A</b></a><ul>
1382                  <li><tt>auth-param</tt>&nbsp;&nbsp;<a href="#rfc.iref.a.2"><b>2.1</b></a></li>
1383                  <li><tt>auth-scheme</tt>&nbsp;&nbsp;<a href="#rfc.iref.a.1"><b>2.1</b></a></li>
1384                  <li>Authorization header field&nbsp;&nbsp;<a href="#rfc.xref.header.authorization.1">2.1</a>, <a href="#rfc.xref.header.authorization.2">3.1</a>, <a href="#rfc.iref.a.3"><b>4.1</b></a>, <a href="#rfc.xref.header.authorization.3">5.3</a></li>
1385               </ul>
1386            </li>
1387            <li><a id="rfc.index.B" href="#rfc.index.B"><b>B</b></a><ul>
1388                  <li><tt>b64token</tt>&nbsp;&nbsp;<a href="#rfc.iref.b.1"><b>2.1</b></a></li>
1389               </ul>
1390            </li>
1391            <li><a id="rfc.index.C" href="#rfc.index.C"><b>C</b></a><ul>
1392                  <li><tt>challenge</tt>&nbsp;&nbsp;<a href="#rfc.iref.c.1"><b>2.1</b></a></li>
1393                  <li><tt>credentials</tt>&nbsp;&nbsp;<a href="#rfc.iref.c.2"><b>2.1</b></a></li>
1394               </ul>
1395            </li>
1396            <li><a id="rfc.index.G" href="#rfc.index.G"><b>G</b></a><ul>
1397                  <li><tt>Grammar</tt>&nbsp;&nbsp;
1398                     <ul>
1399                        <li><tt>auth-param</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.2"><b>2.1</b></a></li>
1400                        <li><tt>auth-scheme</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.1"><b>2.1</b></a></li>
1401                        <li><tt>Authorization</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.6"><b>4.1</b></a></li>
1402                        <li><tt>b64token</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.3"><b>2.1</b></a></li>
1403                        <li><tt>challenge</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.4"><b>2.1</b></a></li>
1404                        <li><tt>credentials</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.5"><b>2.1</b></a></li>
1405                        <li><tt>Proxy-Authenticate</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.7"><b>4.2</b></a></li>
1406                        <li><tt>Proxy-Authorization</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.8"><b>4.3</b></a></li>
1407                        <li><tt>WWW-Authenticate</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.9"><b>4.4</b></a></li>
1408                     </ul>
1409                  </li>
1410               </ul>
1411            </li>
1412            <li><a id="rfc.index.H" href="#rfc.index.H"><b>H</b></a><ul>
1413                  <li>Header Fields&nbsp;&nbsp;
1414                     <ul>
1415                        <li>Authorization&nbsp;&nbsp;<a href="#rfc.xref.header.authorization.1">2.1</a>, <a href="#rfc.xref.header.authorization.2">3.1</a>, <a href="#rfc.iref.h.1"><b>4.1</b></a>, <a href="#rfc.xref.header.authorization.3">5.3</a></li>
1416                        <li>Proxy-Authenticate&nbsp;&nbsp;<a href="#rfc.xref.header.proxy-authenticate.1">3.2</a>, <a href="#rfc.iref.h.2"><b>4.2</b></a>, <a href="#rfc.xref.header.proxy-authenticate.2">5.3</a></li>
1417                        <li>Proxy-Authorization&nbsp;&nbsp;<a href="#rfc.xref.header.proxy-authorization.1">3.2</a>, <a href="#rfc.iref.h.3"><b>4.3</b></a>, <a href="#rfc.xref.header.proxy-authorization.2">5.3</a></li>
1418                        <li>WWW-Authenticate&nbsp;&nbsp;<a href="#rfc.xref.header.www-authenticate.1">3.1</a>, <a href="#rfc.xref.header.www-authenticate.2">4.2</a>, <a href="#rfc.iref.h.4"><b>4.4</b></a>, <a href="#rfc.xref.header.www-authenticate.3">5.3</a></li>
1419                     </ul>
1420                  </li>
1421               </ul>
1422            </li>
1423            <li><a id="rfc.index.P" href="#rfc.index.P"><b>P</b></a><ul>
1424                  <li><em>Part1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.1">1.1</a>, <a href="#rfc.xref.Part1.2">1.2</a>, <a href="#rfc.xref.Part1.3">1.2.1</a>, <a href="#rfc.xref.Part1.4">1.2.1</a>, <a href="#rfc.xref.Part1.5">1.2.1</a>, <a href="#rfc.xref.Part1.6">1.2.1</a>, <a href="#rfc.xref.Part1.7">1.2.1</a>, <a href="#rfc.xref.Part1.8">2.2</a>, <a href="#rfc.xref.Part1.9">2.3.1</a>, <a href="#rfc.xref.Part1.10">4.2</a>, <a href="#rfc.xref.Part1.11">4.4</a>, <a href="#rfc.xref.Part1.12">7</a>, <a href="#Part1"><b>8.1</b></a><ul>
1425                        <li><em>Section 1.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.2">1.2</a></li>
1426                        <li><em>Section 2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.1">1.1</a></li>
1427                        <li><em>Section 2.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.9">2.3.1</a></li>
1428                        <li><em>Section 3.2.1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.4">1.2.1</a>, <a href="#rfc.xref.Part1.5">1.2.1</a></li>
1429                        <li><em>Section 3.2.4</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.6">1.2.1</a>, <a href="#rfc.xref.Part1.7">1.2.1</a></li>
1430                        <li><em>Section 5.5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.8">2.2</a>, <a href="#rfc.xref.Part1.10">4.2</a>, <a href="#rfc.xref.Part1.11">4.4</a></li>
1431                        <li><em>Section 9</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.12">7</a></li>
1432                     </ul>
1433                  </li>
1434                  <li><em>Part6</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.1">4.1</a>, <a href="#Part6"><b>8.1</b></a><ul>
1435                        <li><em>Section 1.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.1">4.1</a></li>
1436                     </ul>
1437                  </li>
1438                  <li>Protection Space&nbsp;&nbsp;<a href="#rfc.iref.p.1">2.2</a></li>
1439                  <li>Proxy-Authenticate header field&nbsp;&nbsp;<a href="#rfc.xref.header.proxy-authenticate.1">3.2</a>, <a href="#rfc.iref.p.2"><b>4.2</b></a>, <a href="#rfc.xref.header.proxy-authenticate.2">5.3</a></li>
1440                  <li>Proxy-Authorization header field&nbsp;&nbsp;<a href="#rfc.xref.header.proxy-authorization.1">3.2</a>, <a href="#rfc.iref.p.3"><b>4.3</b></a>, <a href="#rfc.xref.header.proxy-authorization.2">5.3</a></li>
1441               </ul>
1442            </li>
1443            <li><a id="rfc.index.R" href="#rfc.index.R"><b>R</b></a><ul>
1444                  <li>Realm&nbsp;&nbsp;<a href="#rfc.iref.r.1">2.2</a></li>
1445                  <li><em>RFC2119</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2119.1">1.1</a>, <a href="#RFC2119"><b>8.1</b></a></li>
1446                  <li><em>RFC2616</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2616.1">1</a>, <a href="#RFC2616"><b>8.2</b></a>, <a href="#rfc.xref.RFC2616.2">C.1</a></li>
1447                  <li><em>RFC2617</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2617.1">1</a>, <a href="#rfc.xref.RFC2617.2">1</a>, <a href="#rfc.xref.RFC2617.3">7</a>, <a href="#rfc.xref.RFC2617.4">7</a>, <a href="#RFC2617"><b>8.2</b></a><ul>
1448                        <li><em>Section 6</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2617.4">7</a></li>
1449                     </ul>
1450                  </li>
1451                  <li><em>RFC3864</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3864.1">5.3</a>, <a href="#RFC3864"><b>8.2</b></a></li>
1452                  <li><em>RFC3986</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3986.1">2.1</a>, <a href="#RFC3986"><b>8.2</b></a></li>
1453                  <li><em>RFC4648</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC4648.1">2.1</a>, <a href="#RFC4648"><b>8.2</b></a></li>
1454                  <li><em>RFC5226</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5226.1">2.3</a>, <a href="#RFC5226"><b>8.2</b></a><ul>
1455                        <li><em>Section 4.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5226.1">2.3</a></li>
1456                     </ul>
1457                  </li>
1458                  <li><em>RFC5234</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5234.1">1.2</a>, <a href="#rfc.xref.RFC5234.2">1.2</a>, <a href="#RFC5234"><b>8.1</b></a><ul>
1459                        <li><em>Appendix B.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5234.2">1.2</a></li>
1460                     </ul>
1461                  </li>
1462               </ul>
1463            </li>
1464            <li><a id="rfc.index.S" href="#rfc.index.S"><b>S</b></a><ul>
1465                  <li>Status Codes&nbsp;&nbsp;
1466                     <ul>
1467                        <li>401 Unauthorized&nbsp;&nbsp;<a href="#rfc.iref.s.1"><b>3.1</b></a>, <a href="#rfc.xref.status.401.1">5.2</a></li>
1468                        <li>407 Proxy Authentication Required&nbsp;&nbsp;<a href="#rfc.iref.s.2"><b>3.2</b></a>, <a href="#rfc.xref.status.407.1">5.2</a></li>
1469                     </ul>
1470                  </li>
1471               </ul>
1472            </li>
1473            <li><a id="rfc.index.W" href="#rfc.index.W"><b>W</b></a><ul>
1474                  <li>WWW-Authenticate header field&nbsp;&nbsp;<a href="#rfc.xref.header.www-authenticate.1">3.1</a>, <a href="#rfc.xref.header.www-authenticate.2">4.2</a>, <a href="#rfc.iref.w.1"><b>4.4</b></a>, <a href="#rfc.xref.header.www-authenticate.3">5.3</a></li>
1475               </ul>
1476            </li>
1477         </ul>
1478      </div>
1479      <div class="avoidbreak">
1480         <h1 id="rfc.authors"><a href="#rfc.authors">Authors' Addresses</a></h1>
1481         <p><b>Roy T. Fielding</b>
1482            (editor)
1483            <br>Adobe Systems Incorporated<br>345 Park Ave<br>San Jose, CA&nbsp;95110<br>USA<br>Email: <a href="mailto:fielding@gbiv.com">fielding@gbiv.com</a><br>URI: <a href="http://roy.gbiv.com/">http://roy.gbiv.com/</a></p>
1484         <p><b>Yves Lafon</b>
1485            (editor)
1486            <br>World Wide Web Consortium<br>W3C / ERCIM<br>2004, rte des Lucioles<br>Sophia-Antipolis, AM&nbsp;06902<br>France<br>Email: <a href="mailto:ylafon@w3.org">ylafon@w3.org</a><br>URI: <a href="http://www.raubacapeu.net/people/yves/">http://www.raubacapeu.net/people/yves/</a></p>
1487         <p><b>Julian F. Reschke</b>
1488            (editor)
1489            <br>greenbytes GmbH<br>Hafenweg 16<br>Muenster, NW&nbsp;48155<br>Germany<br>Phone: <a href="tel:+492512807760">+49 251 2807760</a><br>Fax: <a href="fax:+492512807761">+49 251 2807761</a><br>Email: <a href="mailto:julian.reschke@greenbytes.de">julian.reschke@greenbytes.de</a><br>URI: <a href="http://greenbytes.de/tech/webdav/">http://greenbytes.de/tech/webdav/</a></p>
1490      </div>
1491   </body>
1492</html>
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