source: draft-ietf-httpbis/latest/p7-auth.html @ 2584

Last change on this file since 2584 was 2577, checked in by fielding@…, 7 years ago

(editorial) clarify a run-on sentence; see #520

  • Property svn:eol-style set to native
  • Property svn:mime-type set to text/html;charset=utf-8
File size: 88.8 KB
Line 
1<!DOCTYPE html
2  PUBLIC "-//W3C//DTD HTML 4.01//EN">
3<html lang="en">
4   <head profile="http://dublincore.org/documents/2008/08/04/dc-html/">
5      <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
6      <title>Hypertext Transfer Protocol (HTTP/1.1): Authentication</title><script>
7var buttonsAdded = false;
8
9function init() {
10  var fb = document.createElement("div");
11  fb.className = "feedback noprint";
12  fb.setAttribute("onclick", "feedback();");
13  fb.appendChild(document.createTextNode("feedback"));
14
15  var bodyl = document.getElementsByTagName("body");
16  bodyl.item(0).appendChild(fb);
17}
18
19function feedback() {
20  toggleButtonsToElementsByName("h1");
21  toggleButtonsToElementsByName("h2");
22  toggleButtonsToElementsByName("h3");
23  toggleButtonsToElementsByName("h4");
24
25  buttonsAdded = !buttonsAdded;
26}
27
28function toggleButtonsToElementsByName(name) {
29  var list = document.getElementsByTagName(name);
30  for (var i = 0; i < list.length; i++) {
31    toggleButton(list.item(i));
32  }
33}
34
35function toggleButton(node) {
36  if (! buttonsAdded) {
37
38    // docname
39    var template = "mailto:ietf-http-wg@w3.org?subject={docname},%20%22{section}%22&body=<{ref}>:";
40
41    var id = node.getAttribute("id");
42    // better id available?
43    var titlelinks = node.getElementsByTagName("a");
44    for (var i = 0; i < titlelinks.length; i++) {
45      var tl = titlelinks.item(i);
46      if (tl.getAttribute("id")) {
47        id = tl.getAttribute("id");
48      }
49    }
50
51    // ref
52    var ref = window.location.toString();
53    var hash = ref.indexOf("#");
54    if (hash != -1) {
55      ref = ref.substring(0, hash);
56    }
57    if (id != "") {
58      ref += "#" + id;
59    }
60
61    // docname
62    var docname = "draft-ietf-httpbis-p7-auth-latest";
63
64    // section
65    var section = node.textContent;
66    section = section.replace("\u00a0", " ");
67
68    // build URI from template
69    var uri = template.replace("{docname}", encodeURIComponent(docname));
70    uri = uri.replace("{section}", encodeURIComponent(section));
71    uri = uri.replace("{ref}", encodeURIComponent(ref));
72
73    var button = document.createElement("a");
74    button.className = "fbbutton noprint";
75    button.setAttribute("href", uri);
76    button.appendChild(document.createTextNode("send feedback"));
77    node.appendChild(button);
78  }
79  else {
80    var buttons = node.getElementsByTagName("a");
81    for (var i = 0; i < buttons.length; i++) {
82      var b = buttons.item(i);
83      if (b.className == "fbbutton noprint") {
84        node.removeChild(b);
85      }
86    }
87  }
88}</script><style type="text/css" title="Xml2Rfc (sans serif)">
89a {
90  text-decoration: none;
91}
92a.smpl {
93  color: black;
94}
95a:hover {
96  text-decoration: underline;
97}
98a:active {
99  text-decoration: underline;
100}
101address {
102  margin-top: 1em;
103  margin-left: 2em;
104  font-style: normal;
105}
106body {
107  color: black;
108  font-family: cambria, helvetica, arial, sans-serif;
109  font-size: 11pt;
110  margin-right: 2em;
111}
112cite {
113  font-style: normal;
114}
115div.note {
116  margin-left: 2em;
117}
118dl {
119  margin-left: 2em;
120}
121ul.empty {
122  list-style-type: none;
123}
124ul.empty li {
125  margin-top: .5em;
126}
127dl p {
128  margin-left: 0em;
129}
130dt {
131  margin-top: .5em;
132}
133h1 {
134  font-size: 130%;
135  line-height: 21pt;
136  page-break-after: avoid;
137}
138h1.np {
139  page-break-before: always;
140}
141h2 {
142  font-size: 120%;
143  line-height: 15pt;
144  page-break-after: avoid;
145}
146h3 {
147  font-size: 110%;
148  page-break-after: avoid;
149}
150h4, h5, h6 {
151  page-break-after: avoid;
152}
153h1 a, h2 a, h3 a, h4 a, h5 a, h6 a {
154  color: black;
155}
156img {
157  margin-left: 3em;
158}
159li {
160  margin-left: 2em;
161}
162ol {
163  margin-left: 2em;
164}
165ol.la {
166  list-style-type: lower-alpha;
167}
168ol.ua {
169  list-style-type: upper-alpha;
170}
171ol p {
172  margin-left: 0em;
173}
174p {
175  margin-left: 2em;
176}
177pre {
178  margin-left: 3em;
179  background-color: lightyellow;
180  padding: .25em;
181  page-break-inside: avoid;
182}
183pre.text2 {
184  border-style: dotted;
185  border-width: 1px;
186  background-color: #f0f0f0;
187  width: 69em;
188}
189pre.inline {
190  background-color: white;
191  padding: 0em;
192}
193pre.text {
194  border-style: dotted;
195  border-width: 1px;
196  background-color: #f8f8f8;
197  width: 69em;
198}
199pre.drawing {
200  border-style: solid;
201  border-width: 1px;
202  background-color: #f8f8f8;
203  padding: 2em;
204}
205table {
206  margin-left: 2em;
207}
208table.tt {
209  vertical-align: top;
210}
211table.full {
212  border-style: outset;
213  border-width: 1px;
214}
215table.headers {
216  border-style: outset;
217  border-width: 1px;
218}
219table.tt td {
220  vertical-align: top;
221}
222table.full td {
223  border-style: inset;
224  border-width: 1px;
225}
226table.tt th {
227  vertical-align: top;
228}
229table.full th {
230  border-style: inset;
231  border-width: 1px;
232}
233table.headers th {
234  border-style: none none inset none;
235  border-width: 1px;
236}
237table.left {
238  margin-right: auto;
239}
240table.right {
241  margin-left: auto;
242}
243table.center {
244  margin-left: auto;
245  margin-right: auto;
246}
247caption {
248  caption-side: bottom;
249  font-weight: bold;
250  font-size: 10pt;
251  margin-top: .5em;
252}
253
254table.header {
255  border-spacing: 1px;
256  width: 95%;
257  font-size: 11pt;
258  color: white;
259}
260td.top {
261  vertical-align: top;
262}
263td.topnowrap {
264  vertical-align: top;
265  white-space: nowrap;
266}
267table.header td {
268  background-color: gray;
269  width: 50%;
270}
271table.header a {
272  color: white;
273}
274td.reference {
275  vertical-align: top;
276  white-space: nowrap;
277  padding-right: 1em;
278}
279thead {
280  display:table-header-group;
281}
282ul.toc, ul.toc ul {
283  list-style: none;
284  margin-left: 1.5em;
285  padding-left: 0em;
286}
287ul.toc li {
288  line-height: 150%;
289  font-weight: bold;
290  margin-left: 0em;
291}
292ul.toc li li {
293  line-height: normal;
294  font-weight: normal;
295  font-size: 10pt;
296  margin-left: 0em;
297}
298li.excluded {
299  font-size: 0pt;
300}
301ul p {
302  margin-left: 0em;
303}
304.title, .filename, h1, h2, h3, h4 {
305  font-family: candara, helvetica, arial, sans-serif;
306}
307samp, tt, code, pre {
308  font: consolas, monospace;
309}
310ul.ind, ul.ind ul {
311  list-style: none;
312  margin-left: 1.5em;
313  padding-left: 0em;
314  page-break-before: avoid;
315}
316ul.ind li {
317  font-weight: bold;
318  line-height: 200%;
319  margin-left: 0em;
320}
321ul.ind li li {
322  font-weight: normal;
323  line-height: 150%;
324  margin-left: 0em;
325}
326.avoidbreak {
327  page-break-inside: avoid;
328}
329.bcp14 {
330  font-style: normal;
331  text-transform: lowercase;
332  font-variant: small-caps;
333}
334.comment {
335  background-color: yellow;
336}
337.center {
338  text-align: center;
339}
340.error {
341  color: red;
342  font-style: italic;
343  font-weight: bold;
344}
345.figure {
346  font-weight: bold;
347  text-align: center;
348  font-size: 10pt;
349}
350.filename {
351  color: #333333;
352  font-size: 75%;
353  font-weight: bold;
354  line-height: 21pt;
355  text-align: center;
356}
357.fn {
358  font-weight: bold;
359}
360.left {
361  text-align: left;
362}
363.right {
364  text-align: right;
365}
366.title {
367  color: green;
368  font-size: 150%;
369  line-height: 18pt;
370  font-weight: bold;
371  text-align: center;
372  margin-top: 36pt;
373}
374.warning {
375  font-size: 130%;
376  background-color: yellow;
377}
378.feedback {
379  position: fixed;
380  bottom: 1%;
381  right: 1%;
382  padding: 3px 5px;
383  color: white;
384  border-radius: 5px;
385  background: #a00000;
386  border: 1px solid silver;
387}
388.fbbutton {
389  margin-left: 1em;
390  color: #303030;
391  font-size: small;
392  font-weight: normal;
393  background: #d0d000;
394  padding: 1px 4px;
395  border: 1px solid silver;
396  border-radius: 5px;
397}
398
399@media print {
400  .noprint {
401    display: none;
402  }
403
404  a {
405    color: black;
406    text-decoration: none;
407  }
408
409  table.header {
410    width: 90%;
411  }
412
413  td.header {
414    width: 50%;
415    color: black;
416    background-color: white;
417    vertical-align: top;
418    font-size: 110%;
419  }
420
421  ul.toc a:nth-child(2)::after {
422    content: leader('.') target-counter(attr(href), page);
423  }
424
425  ul.ind li li a {
426    content: target-counter(attr(href), page);
427  }
428
429  .print2col {
430    column-count: 2;
431    -moz-column-count: 2;
432    column-fill: auto;
433  }
434}
435
436@page {
437  @top-left {
438       content: "Internet-Draft";
439  }
440  @top-right {
441       content: "January 2014";
442  }
443  @top-center {
444       content: "HTTP/1.1 Authentication";
445  }
446  @bottom-left {
447       content: "Fielding & Reschke";
448  }
449  @bottom-center {
450       content: "Expires July 28, 2014";
451  }
452  @bottom-right {
453       content: "[Page " counter(page) "]";
454  }
455}
456
457@page:first {
458    @top-left {
459      content: normal;
460    }
461    @top-right {
462      content: normal;
463    }
464    @top-center {
465      content: normal;
466    }
467}
468</style><link rel="Contents" href="#rfc.toc">
469      <link rel="Author" href="#rfc.authors">
470      <link rel="Copyright" href="#rfc.copyrightnotice">
471      <link rel="Index" href="#rfc.index">
472      <link rel="Chapter" title="1 Introduction" href="#rfc.section.1">
473      <link rel="Chapter" title="2 Access Authentication Framework" href="#rfc.section.2">
474      <link rel="Chapter" title="3 Status Code Definitions" href="#rfc.section.3">
475      <link rel="Chapter" title="4 Header Field Definitions" href="#rfc.section.4">
476      <link rel="Chapter" title="5 IANA Considerations" href="#rfc.section.5">
477      <link rel="Chapter" title="6 Security Considerations" href="#rfc.section.6">
478      <link rel="Chapter" title="7 Acknowledgments" href="#rfc.section.7">
479      <link rel="Chapter" href="#rfc.section.8" title="8 References">
480      <link rel="Appendix" title="A Changes from RFCs 2616 and 2617" href="#rfc.section.A">
481      <link rel="Appendix" title="B Imported ABNF" href="#rfc.section.B">
482      <link rel="Appendix" title="C Collected ABNF" href="#rfc.section.C">
483      <link rel="Appendix" title="D Change Log (to be removed by RFC Editor before publication)" href="#rfc.section.D">
484      <link href="p6-cache.html" rel="prev">
485      <meta name="generator" content="http://greenbytes.de/tech/webdav/rfc2629.xslt, Revision 1.611, 2013/11/27 12:23:51, XSLT vendor: SAXON 8.9 from Saxonica http://www.saxonica.com/">
486      <link rel="schema.dct" href="http://purl.org/dc/terms/">
487      <meta name="dct.creator" content="Fielding, R.">
488      <meta name="dct.creator" content="Reschke, J. F.">
489      <meta name="dct.identifier" content="urn:ietf:id:draft-ietf-httpbis-p7-auth-latest">
490      <meta name="dct.issued" scheme="ISO8601" content="2014-01-24">
491      <meta name="dct.replaces" content="urn:ietf:rfc:2616">
492      <meta name="dct.abstract" content="The Hypertext Transfer Protocol (HTTP) is a stateless application-level protocol for distributed, collaborative, hypermedia information systems. This document defines the HTTP Authentication framework.">
493      <meta name="description" content="The Hypertext Transfer Protocol (HTTP) is a stateless application-level protocol for distributed, collaborative, hypermedia information systems. This document defines the HTTP Authentication framework.">
494   </head>
495   <body onload="init();">
496      <table class="header">
497         <tbody>
498            <tr>
499               <td class="left">HTTPbis Working Group</td>
500               <td class="right">R. Fielding, Editor</td>
501            </tr>
502            <tr>
503               <td class="left">Internet-Draft</td>
504               <td class="right">Adobe</td>
505            </tr>
506            <tr>
507               <td class="left">Obsoletes: <a href="http://tools.ietf.org/html/rfc2616">2616</a> (if approved)
508               </td>
509               <td class="right">J. Reschke, Editor</td>
510            </tr>
511            <tr>
512               <td class="left">Updates: <a href="http://tools.ietf.org/html/rfc2617">2617</a> (if approved)
513               </td>
514               <td class="right">greenbytes</td>
515            </tr>
516            <tr>
517               <td class="left">Intended status: Standards Track</td>
518               <td class="right">January 24, 2014</td>
519            </tr>
520            <tr>
521               <td class="left">Expires: July 28, 2014</td>
522               <td class="right"></td>
523            </tr>
524         </tbody>
525      </table>
526      <p class="title">Hypertext Transfer Protocol (HTTP/1.1): Authentication<br><span class="filename">draft-ietf-httpbis-p7-auth-latest</span></p>
527      <h1 id="rfc.abstract"><a href="#rfc.abstract">Abstract</a></h1>
528      <p>The Hypertext Transfer Protocol (HTTP) is a stateless application-level protocol for distributed, collaborative, hypermedia
529         information systems. This document defines the HTTP Authentication framework.
530      </p>
531      <h1 id="rfc.note.1"><a href="#rfc.note.1">Editorial Note (To be removed by RFC Editor)</a></h1>
532      <p>Discussion of this draft takes place on the HTTPBIS working group mailing list (ietf-http-wg@w3.org), which is archived at &lt;<a href="http://lists.w3.org/Archives/Public/ietf-http-wg/">http://lists.w3.org/Archives/Public/ietf-http-wg/</a>&gt;.
533      </p>
534      <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;.
535      </p>
536      <p>The changes in this draft are summarized in <a href="#changes.since.25" title="Since draft-ietf-httpbis-p7-auth-25">Appendix&nbsp;D.2</a>.
537      </p>
538      <div id="rfc.status">
539         <h1><a href="#rfc.status">Status of This Memo</a></h1>
540         <p>This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79.</p>
541         <p>Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute
542            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>.
543         </p>
544         <p>Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other
545            documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as “work
546            in progress”.
547         </p>
548         <p>This Internet-Draft will expire on July 28, 2014.</p>
549      </div>
550      <div id="rfc.copyrightnotice">
551         <h1><a href="#rfc.copyrightnotice">Copyright Notice</a></h1>
552         <p>Copyright © 2014 IETF Trust and the persons identified as the document authors. All rights reserved.</p>
553         <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
554            and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License
555            text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified
556            BSD License.
557         </p>
558         <p>This document may contain material from IETF Documents or IETF Contributions published or made publicly available before November
559            10, 2008. The person(s) controlling the copyright in some of this material may not have granted the IETF Trust the right to
560            allow modifications of such material outside the IETF Standards Process. Without obtaining an adequate license from the person(s)
561            controlling the copyright in such materials, this document may not be modified outside the IETF Standards Process, and derivative
562            works of it may not be created outside the IETF Standards Process, except to format it for publication as an RFC or to translate
563            it into languages other than English.
564         </p>
565      </div>
566      <hr class="noprint">
567      <h1 class="np" id="rfc.toc"><a href="#rfc.toc">Table of Contents</a></h1>
568      <ul class="toc">
569         <li><a href="#rfc.section.1">1.</a>&nbsp;&nbsp;&nbsp;<a href="#introduction">Introduction</a><ul>
570               <li><a href="#rfc.section.1.1">1.1</a>&nbsp;&nbsp;&nbsp;<a href="#conformance">Conformance and Error Handling</a></li>
571               <li><a href="#rfc.section.1.2">1.2</a>&nbsp;&nbsp;&nbsp;<a href="#notation">Syntax Notation</a></li>
572            </ul>
573         </li>
574         <li><a href="#rfc.section.2">2.</a>&nbsp;&nbsp;&nbsp;<a href="#access.authentication.framework">Access Authentication Framework</a><ul>
575               <li><a href="#rfc.section.2.1">2.1</a>&nbsp;&nbsp;&nbsp;<a href="#challenge.and.response">Challenge and Response</a></li>
576               <li><a href="#rfc.section.2.2">2.2</a>&nbsp;&nbsp;&nbsp;<a href="#protection.space">Protection Space (Realm)</a></li>
577            </ul>
578         </li>
579         <li><a href="#rfc.section.3">3.</a>&nbsp;&nbsp;&nbsp;<a href="#status.code.definitions">Status Code Definitions</a><ul>
580               <li><a href="#rfc.section.3.1">3.1</a>&nbsp;&nbsp;&nbsp;<a href="#status.401">401 Unauthorized</a></li>
581               <li><a href="#rfc.section.3.2">3.2</a>&nbsp;&nbsp;&nbsp;<a href="#status.407">407 Proxy Authentication Required</a></li>
582            </ul>
583         </li>
584         <li><a href="#rfc.section.4">4.</a>&nbsp;&nbsp;&nbsp;<a href="#header.field.definitions">Header Field Definitions</a><ul>
585               <li><a href="#rfc.section.4.1">4.1</a>&nbsp;&nbsp;&nbsp;<a href="#header.www-authenticate">WWW-Authenticate</a></li>
586               <li><a href="#rfc.section.4.2">4.2</a>&nbsp;&nbsp;&nbsp;<a href="#header.authorization">Authorization</a></li>
587               <li><a href="#rfc.section.4.3">4.3</a>&nbsp;&nbsp;&nbsp;<a href="#header.proxy-authenticate">Proxy-Authenticate</a></li>
588               <li><a href="#rfc.section.4.4">4.4</a>&nbsp;&nbsp;&nbsp;<a href="#header.proxy-authorization">Proxy-Authorization</a></li>
589            </ul>
590         </li>
591         <li><a href="#rfc.section.5">5.</a>&nbsp;&nbsp;&nbsp;<a href="#IANA.considerations">IANA Considerations</a><ul>
592               <li><a href="#rfc.section.5.1">5.1</a>&nbsp;&nbsp;&nbsp;<a href="#authentication.scheme.registry">Authentication Scheme Registry</a><ul>
593                     <li><a href="#rfc.section.5.1.1">5.1.1</a>&nbsp;&nbsp;&nbsp;<a href="#authentication.scheme.registry.procedure">Procedure</a></li>
594                     <li><a href="#rfc.section.5.1.2">5.1.2</a>&nbsp;&nbsp;&nbsp;<a href="#considerations.for.new.authentication.schemes">Considerations for New Authentication Schemes</a></li>
595                  </ul>
596               </li>
597               <li><a href="#rfc.section.5.2">5.2</a>&nbsp;&nbsp;&nbsp;<a href="#status.code.registration">Status Code Registration</a></li>
598               <li><a href="#rfc.section.5.3">5.3</a>&nbsp;&nbsp;&nbsp;<a href="#header.field.registration">Header Field Registration</a></li>
599            </ul>
600         </li>
601         <li><a href="#rfc.section.6">6.</a>&nbsp;&nbsp;&nbsp;<a href="#security.considerations">Security Considerations</a><ul>
602               <li><a href="#rfc.section.6.1">6.1</a>&nbsp;&nbsp;&nbsp;<a href="#confidentiality.of.credentials">Confidentiality of Credentials</a></li>
603               <li><a href="#rfc.section.6.2">6.2</a>&nbsp;&nbsp;&nbsp;<a href="#auth.credentials.and.idle.clients">Authentication Credentials and Idle Clients</a></li>
604               <li><a href="#rfc.section.6.3">6.3</a>&nbsp;&nbsp;&nbsp;<a href="#protection.spaces">Protection Spaces</a></li>
605            </ul>
606         </li>
607         <li><a href="#rfc.section.7">7.</a>&nbsp;&nbsp;&nbsp;<a href="#acks">Acknowledgments</a></li>
608         <li><a href="#rfc.section.8">8.</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.references">References</a><ul>
609               <li><a href="#rfc.section.8.1">8.1</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.references.1">Normative References</a></li>
610               <li><a href="#rfc.section.8.2">8.2</a>&nbsp;&nbsp;&nbsp;<a href="#rfc.references.2">Informative References</a></li>
611            </ul>
612         </li>
613         <li><a href="#rfc.authors">Authors' Addresses</a></li>
614         <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>
615         <li><a href="#rfc.section.B">B.</a>&nbsp;&nbsp;&nbsp;<a href="#imported.abnf">Imported ABNF</a></li>
616         <li><a href="#rfc.section.C">C.</a>&nbsp;&nbsp;&nbsp;<a href="#collected.abnf">Collected ABNF</a></li>
617         <li><a href="#rfc.section.D">D.</a>&nbsp;&nbsp;&nbsp;<a href="#change.log">Change Log (to be removed by RFC Editor before publication)</a><ul>
618               <li><a href="#rfc.section.D.1">D.1</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.24">Since draft-ietf-httpbis-p7-auth-24</a></li>
619               <li><a href="#rfc.section.D.2">D.2</a>&nbsp;&nbsp;&nbsp;<a href="#changes.since.25">Since draft-ietf-httpbis-p7-auth-25</a></li>
620            </ul>
621         </li>
622         <li><a href="#rfc.index">Index</a></li>
623      </ul>
624      <div id="introduction">
625         <h1 id="rfc.section.1" class="np"><a href="#rfc.section.1">1.</a>&nbsp;<a href="#introduction">Introduction</a></h1>
626         <p id="rfc.section.1.p.1">HTTP provides a general framework for access control and authentication, via an extensible set of challenge-response authentication
627            schemes, which can be used by a server to challenge a client request and by a client to provide authentication information.
628            This document defines HTTP/1.1 authentication in terms of the architecture defined in <a href="#Part1" id="rfc.xref.Part1.1"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a>, including the general framework previously described in <cite title="HTTP Authentication: Basic and Digest Access Authentication" id="rfc.xref.RFC2617.1">RFC 2617</cite> and the related fields and status codes previously defined in <cite title="Hypertext Transfer Protocol -- HTTP/1.1" id="rfc.xref.RFC2616.1">RFC 2616</cite>.
629         </p>
630         <p id="rfc.section.1.p.2">The IANA Authentication Scheme Registry (<a href="#authentication.scheme.registry" title="Authentication Scheme Registry">Section&nbsp;5.1</a>) lists registered authentication schemes and their corresponding specifications, including the "basic" and "digest" authentication
631            schemes previously defined by <cite title="HTTP Authentication: Basic and Digest Access Authentication" id="rfc.xref.RFC2617.2">RFC 2617</cite>.
632         </p>
633         <div id="conformance">
634            <h2 id="rfc.section.1.1"><a href="#rfc.section.1.1">1.1</a>&nbsp;<a href="#conformance">Conformance and Error Handling</a></h2>
635            <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"
636               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>.
637            </p>
638            <p id="rfc.section.1.1.p.2">Conformance criteria and considerations regarding error handling are defined in <a href="p1-messaging.html#conformance" title="Conformance and Error Handling">Section 2.5</a> of <a href="#Part1" id="rfc.xref.Part1.2"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a>.
639            </p>
640         </div>
641         <div id="notation">
642            <h2 id="rfc.section.1.2"><a href="#rfc.section.1.2">1.2</a>&nbsp;<a href="#notation">Syntax Notation</a></h2>
643            <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 a list extension, defined in <a href="p1-messaging.html#abnf.extension" title="ABNF list extension: #rule">Section 7</a> of <a href="#Part1" id="rfc.xref.Part1.3"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a>, that allows for compact definition of comma-separated lists using a '#' operator (similar to how the '*' operator indicates
644               repetition). <a href="#imported.abnf" title="Imported ABNF">Appendix&nbsp;B</a> describes rules imported from other documents. <a href="#collected.abnf" title="Collected ABNF">Appendix&nbsp;C</a> shows the collected grammar with all list operators expanded to standard ABNF notation.
645            </p>
646         </div>
647      </div>
648      <div id="access.authentication.framework">
649         <h1 id="rfc.section.2"><a href="#rfc.section.2">2.</a>&nbsp;<a href="#access.authentication.framework">Access Authentication Framework</a></h1>
650         <div id="challenge.and.response">
651            <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>
652            <p id="rfc.section.2.1.p.1">HTTP provides a simple challenge-response authentication framework that can be used by a server to challenge a client request
653               and by a client to provide authentication information. It uses a case-insensitive token as a means to identify the authentication
654               scheme, followed by additional information necessary for achieving authentication via that scheme. The latter can either be
655               a comma-separated list of parameters or a single sequence of characters capable of holding base64-encoded information.
656            </p>
657            <p id="rfc.section.2.1.p.2">Authentication parameters are name=value pairs, where the name token is matched case-insensitively, and each parameter name <em class="bcp14">MUST</em> only occur once per challenge.
658            </p>
659            <div id="rfc.figure.u.1"></div><pre class="inline"><span id="rfc.iref.g.1"></span><span id="rfc.iref.g.2"></span><span id="rfc.iref.g.3"></span>  auth-scheme    = <a href="#imported.abnf" class="smpl">token</a>
660 
661  auth-param     = <a href="#imported.abnf" class="smpl">token</a> <a href="#imported.abnf" class="smpl">BWS</a> "=" <a href="#imported.abnf" class="smpl">BWS</a> ( <a href="#imported.abnf" class="smpl">token</a> / <a href="#imported.abnf" class="smpl">quoted-string</a> )
662
663  token68        = 1*( <a href="#imported.abnf" class="smpl">ALPHA</a> / <a href="#imported.abnf" class="smpl">DIGIT</a> /
664                       "-" / "." / "_" / "~" / "+" / "/" ) *"="
665</pre><p id="rfc.section.2.1.p.4">The "token68" 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,
666               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>).
667            </p>
668            <p id="rfc.section.2.1.p.5">A <a href="#status.401" class="smpl">401 (Unauthorized)</a> response message is used by an origin server to challenge the authorization of a user agent, including a <a href="#header.www-authenticate" class="smpl">WWW-Authenticate</a> header field containing at least one challenge applicable to the requested resource.
669            </p>
670            <p id="rfc.section.2.1.p.6">A <a href="#status.407" class="smpl">407 (Proxy Authentication Required)</a> response message is used by a proxy to challenge the authorization of a client, including a <a href="#header.proxy-authenticate" class="smpl">Proxy-Authenticate</a> header field containing at least one challenge applicable to the proxy for the requested resource.
671            </p>
672            <div id="rfc.figure.u.2"></div><pre class="inline"><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="#imported.abnf" class="smpl">SP</a> ( <a href="#challenge.and.response" class="smpl">token68</a> / #<a href="#challenge.and.response" class="smpl">auth-param</a> ) ]
673</pre><div class="note" id="rfc.section.2.1.p.8">
674               <p><b>Note:</b> Many clients fail to parse a challenge that contains an unknown scheme. A workaround for this problem is to list well-supported
675                  schemes (such as "basic") first.
676               </p>
677            </div>
678            <p id="rfc.section.2.1.p.9">A user agent that wishes to authenticate itself with an origin server — usually, but not necessarily, after receiving a <a href="#status.401" class="smpl">401 (Unauthorized)</a> — can do so by including an <a href="#header.authorization" class="smpl">Authorization</a> header field with the request.
679            </p>
680            <p id="rfc.section.2.1.p.10">A client that wishes to authenticate itself with a proxy — usually, but not necessarily, after receiving a <a href="#status.407" class="smpl">407 (Proxy Authentication Required)</a> — can do so by including a <a href="#header.proxy-authorization" class="smpl">Proxy-Authorization</a> header field with the request.
681            </p>
682            <p id="rfc.section.2.1.p.11">Both the <a href="#header.authorization" class="smpl">Authorization</a> field value and the <a href="#header.proxy-authorization" class="smpl">Proxy-Authorization</a> field value contain the client's credentials for the realm of the resource being requested, based upon a challenge received
683               in a response (possibly at some point in the past). When creating their values, the user agent ought to do so by selecting
684               the challenge with what it considers to be the most secure auth-scheme that it understands, obtaining credentials from the
685               user as appropriate. Transmission of credentials within header field values implies significant security considerations regarding
686               the confidentiality of the underlying connection, as described in <a href="#confidentiality.of.credentials" title="Confidentiality of Credentials">Section&nbsp;6.1</a>.
687            </p>
688            <div id="rfc.figure.u.3"></div><pre class="inline"><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="#imported.abnf" class="smpl">SP</a> ( <a href="#challenge.and.response" class="smpl">token68</a> / #<a href="#challenge.and.response" class="smpl">auth-param</a> ) ]
689</pre><p id="rfc.section.2.1.p.13">Upon receipt of a request for a protected resource that omits credentials, contains invalid credentials (e.g., a bad password)
690               or partial credentials (e.g., when the authentication scheme requires more than one round trip), an origin server <em class="bcp14">SHOULD</em> send a <a href="#status.401" class="smpl">401 (Unauthorized)</a> response that contains a <a href="#header.www-authenticate" class="smpl">WWW-Authenticate</a> header field with at least one (possibly new) challenge applicable to the requested resource.
691            </p>
692            <p id="rfc.section.2.1.p.14">Likewise, upon receipt of a request that omits proxy credentials or contains invalid or partial proxy credentials, a proxy
693               that requires authentication <em class="bcp14">SHOULD</em> generate a <a href="#status.407" class="smpl">407 (Proxy Authentication Required)</a> response that contains a <a href="#header.proxy-authenticate" class="smpl">Proxy-Authenticate</a> header field with at least one (possibly new) challenge applicable to the proxy.
694            </p>
695            <p id="rfc.section.2.1.p.15">A server that receives valid credentials which are not adequate to gain access ought to respond with the <a href="p2-semantics.html#status.403" class="smpl">403 (Forbidden)</a> status code (<a href="p2-semantics.html#status.403" title="403 Forbidden">Section 6.5.3</a> of <a href="#Part2" id="rfc.xref.Part2.1"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content">[Part2]</cite></a>).
696            </p>
697            <p id="rfc.section.2.1.p.16">HTTP does not restrict applications to this simple challenge-response framework for access authentication. Additional mechanisms
698               can be used, such as authentication at the transport level or via message encapsulation, and with additional header fields
699               specifying authentication information. However, such additional mechanisms are not defined by this specification.
700            </p>
701         </div>
702         <div id="protection.space">
703            <div id="rfc.iref.p.1"></div>
704            <div id="rfc.iref.r.1"></div>
705            <div id="rfc.iref.c.1"></div>
706            <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>
707            <p id="rfc.section.2.2.p.1">The "<dfn>realm</dfn>" authentication parameter is reserved for use by authentication schemes that wish to indicate a scope of protection.
708            </p>
709            <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.Part1.4"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a>) of the server being accessed, in combination with the realm value if present. These realms allow the protected resources
710               on a server to be partitioned into a set of protection spaces, each with its own authentication scheme and/or authorization
711               database. The realm value is a string, generally assigned by the origin server, which can have additional semantics specific
712               to the authentication scheme. Note that a response can have multiple challenges with the same auth-scheme but different realms.
713            </p>
714            <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
715               authorized, the user agent <em class="bcp14">MAY</em> reuse the same credentials for all other requests within that protection space for a period of time determined by the authentication
716               scheme, parameters, and/or user preferences (such as a configurable inactivity timeout). Unless specifically allowed by the
717               authentication scheme, a single protection space cannot extend outside the scope of its server.
718            </p>
719            <p id="rfc.section.2.2.p.4">For historical reasons, a sender <em class="bcp14">MUST</em> only generate the quoted-string syntax. Recipients might have to support both token and quoted-string syntax for maximum interoperability
720               with existing clients that have been accepting both notations for a long time.
721            </p>
722         </div>
723      </div>
724      <div id="status.code.definitions">
725         <h1 id="rfc.section.3"><a href="#rfc.section.3">3.</a>&nbsp;<a href="#status.code.definitions">Status Code Definitions</a></h1>
726         <div id="status.401">
727            <div id="rfc.iref.8"></div>
728            <h2 id="rfc.section.3.1"><a href="#rfc.section.3.1">3.1</a>&nbsp;<a href="#status.401">401 Unauthorized</a></h2>
729            <p id="rfc.section.3.1.p.1">The <dfn>401 (Unauthorized)</dfn> status code indicates that the request has not been applied because it lacks valid authentication credentials for the target
730               resource. The server generating a 401 response <em class="bcp14">MUST</em> send a <a href="#header.www-authenticate" class="smpl">WWW-Authenticate</a> header field (<a href="#header.www-authenticate" id="rfc.xref.header.www-authenticate.1" title="WWW-Authenticate">Section&nbsp;4.1</a>) containing at least one challenge applicable to the target resource.
731            </p>
732            <p id="rfc.section.3.1.p.2">If the request included authentication credentials, then the 401 response indicates that authorization has been refused for
733               those credentials. The user agent <em class="bcp14">MAY</em> repeat the request with a new or replaced <a href="#header.authorization" class="smpl">Authorization</a> header field (<a href="#header.authorization" id="rfc.xref.header.authorization.1" title="Authorization">Section&nbsp;4.2</a>). If the 401 response contains the same challenge as the prior response, and the user agent has already attempted authentication
734               at least once, then the user agent <em class="bcp14">SHOULD</em> present the enclosed representation to the user, since it usually contains relevant diagnostic information.
735            </p>
736         </div>
737         <div id="status.407">
738            <div id="rfc.iref.8"></div>
739            <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>
740            <p id="rfc.section.3.2.p.1">The <dfn>407 (Proxy Authentication Required)</dfn> status code is similar to <a href="#status.401" class="smpl">401 (Unauthorized)</a>, but indicates that the client needs to authenticate itself in order to use a proxy. The proxy <em class="bcp14">MUST</em> send a <a href="#header.proxy-authenticate" class="smpl">Proxy-Authenticate</a> header field (<a href="#header.proxy-authenticate" id="rfc.xref.header.proxy-authenticate.1" title="Proxy-Authenticate">Section&nbsp;4.3</a>) containing a challenge applicable to that proxy for the target resource. The client <em class="bcp14">MAY</em> repeat the request with a new or replaced <a href="#header.proxy-authorization" class="smpl">Proxy-Authorization</a> header field (<a href="#header.proxy-authorization" id="rfc.xref.header.proxy-authorization.1" title="Proxy-Authorization">Section&nbsp;4.4</a>).
741            </p>
742         </div>
743      </div>
744      <div id="header.field.definitions">
745         <h1 id="rfc.section.4"><a href="#rfc.section.4">4.</a>&nbsp;<a href="#header.field.definitions">Header Field Definitions</a></h1>
746         <p id="rfc.section.4.p.1">This section defines the syntax and semantics of header fields related to the HTTP authentication framework.</p>
747         <div id="header.www-authenticate">
748            <div id="rfc.iref.w.1"></div>
749            <h2 id="rfc.section.4.1"><a href="#rfc.section.4.1">4.1</a>&nbsp;<a href="#header.www-authenticate">WWW-Authenticate</a></h2>
750            <p id="rfc.section.4.1.p.1">The "WWW-Authenticate" header field indicates the authentication scheme(s) and parameters applicable to the target resource.</p>
751            <div id="rfc.figure.u.4"></div><pre class="inline"><span id="rfc.iref.g.6"></span>  <a href="#header.www-authenticate" class="smpl">WWW-Authenticate</a> = 1#<a href="#challenge.and.response" class="smpl">challenge</a>
752</pre><p id="rfc.section.4.1.p.3">A server generating a <a href="#status.401" class="smpl">401 (Unauthorized)</a> response <em class="bcp14">MUST</em> send a WWW-Authenticate header field containing at least one challenge. A server <em class="bcp14">MAY</em> generate a WWW-Authenticate header field in other response messages to indicate that supplying credentials (or different credentials)
753               might affect the response.
754            </p>
755            <p id="rfc.section.4.1.p.4">A proxy forwarding a response <em class="bcp14">MUST NOT</em> modify any <a href="#header.www-authenticate" class="smpl">WWW-Authenticate</a> fields in that response.
756            </p>
757            <p id="rfc.section.4.1.p.5">User agents are advised to take special care in parsing the field value, as it might contain more than one challenge, and
758               each challenge can contain a comma-separated list of authentication parameters. Furthermore, the header field itself can occur
759               multiple times.
760            </p>
761            <div id="rfc.figure.u.5"></div>
762            <p>For instance:</p><pre class="text">  WWW-Authenticate: Newauth realm="apps", type=1,
763                    title="Login to \"apps\"", Basic realm="simple"
764</pre><p>This header field contains two challenges; one for the "Newauth" scheme with a realm value of "apps", and two additional parameters
765               "type" and "title", and another one for the "Basic" scheme with a realm value of "simple".
766            </p>
767            <div class="note" id="rfc.section.4.1.p.7">
768               <p><b>Note:</b> The challenge grammar production uses the list syntax as well. Therefore, a sequence of comma, whitespace, and comma can be
769                  considered either as applying to the preceding challenge, or to be an empty entry in the list of challenges. In practice,
770                  this ambiguity does not affect the semantics of the header field value and thus is harmless.
771               </p>
772            </div>
773         </div>
774         <div id="header.authorization">
775            <div id="rfc.iref.a.1"></div>
776            <h2 id="rfc.section.4.2"><a href="#rfc.section.4.2">4.2</a>&nbsp;<a href="#header.authorization">Authorization</a></h2>
777            <p id="rfc.section.4.2.p.1">The "Authorization" header field allows a user agent to authenticate itself with an origin server — usually, but not necessarily,
778               after receiving a <a href="#status.401" class="smpl">401 (Unauthorized)</a> response. Its value consists of credentials containing the authentication information of the user agent for the realm of the
779               resource being requested.
780            </p>
781            <div id="rfc.figure.u.6"></div><pre class="inline"><span id="rfc.iref.g.7"></span>  <a href="#header.authorization" class="smpl">Authorization</a> = <a href="#challenge.and.response" class="smpl">credentials</a>
782</pre><p id="rfc.section.4.2.p.3">If a request is authenticated and a realm specified, the same credentials are presumed to be valid for all other requests
783               within this realm (assuming that the authentication scheme itself does not require otherwise, such as credentials that vary
784               according to a challenge value or using synchronized clocks).
785            </p>
786            <p id="rfc.section.4.2.p.4">A proxy forwarding a request <em class="bcp14">MUST NOT</em> modify any <a href="#header.authorization" class="smpl">Authorization</a> fields in that request. See <a href="p6-cache.html#caching.authenticated.responses" title="Storing Responses to Authenticated Requests">Section 3.2</a> of <a href="#Part6" id="rfc.xref.Part6.1"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Caching">[Part6]</cite></a> for details of and requirements pertaining to handling of the Authorization field by HTTP caches.
787            </p>
788         </div>
789         <div id="header.proxy-authenticate">
790            <div id="rfc.iref.p.2"></div>
791            <h2 id="rfc.section.4.3"><a href="#rfc.section.4.3">4.3</a>&nbsp;<a href="#header.proxy-authenticate">Proxy-Authenticate</a></h2>
792            <p id="rfc.section.4.3.p.1">The "Proxy-Authenticate" header field consists of at least one challenge that indicates the authentication scheme(s) and parameters
793               applicable 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.Part1.5"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a>). A proxy <em class="bcp14">MUST</em> send at least one Proxy-Authenticate header field in each <a href="#status.407" class="smpl">407 (Proxy Authentication Required)</a> response that it generates.
794            </p>
795            <div id="rfc.figure.u.7"></div><pre class="inline"><span id="rfc.iref.g.8"></span>  <a href="#header.proxy-authenticate" class="smpl">Proxy-Authenticate</a> = 1#<a href="#challenge.and.response" class="smpl">challenge</a>
796</pre><p id="rfc.section.4.3.p.3">Unlike <a href="#header.www-authenticate" class="smpl">WWW-Authenticate</a>, the Proxy-Authenticate header field applies only to the next outbound client on the response chain. This is because only
797               the client that chose a given proxy is likely to have the credentials necessary for authentication. However, when multiple
798               proxies are used within the same administrative domain, such as office and regional caching proxies within a large corporate
799               network, it is common for credentials to be generated by the user agent and passed through the hierarchy until consumed. Hence,
800               in such a configuration, it will appear as if Proxy-Authenticate is being forwarded because each proxy will send the same
801               challenge set.
802            </p>
803            <p id="rfc.section.4.3.p.4">Note that the parsing considerations for <a href="#header.www-authenticate" class="smpl">WWW-Authenticate</a> 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;4.1</a> for details.
804            </p>
805         </div>
806         <div id="header.proxy-authorization">
807            <div id="rfc.iref.p.3"></div>
808            <h2 id="rfc.section.4.4"><a href="#rfc.section.4.4">4.4</a>&nbsp;<a href="#header.proxy-authorization">Proxy-Authorization</a></h2>
809            <p id="rfc.section.4.4.p.1">The "Proxy-Authorization" header field allows the client to identify itself (or its user) to a proxy that requires authentication.
810               Its value consists of credentials containing the authentication information of the client for the proxy and/or realm of the
811               resource being requested.
812            </p>
813            <div id="rfc.figure.u.8"></div><pre class="inline"><span id="rfc.iref.g.9"></span>  <a href="#header.proxy-authorization" class="smpl">Proxy-Authorization</a> = <a href="#challenge.and.response" class="smpl">credentials</a>
814</pre><p id="rfc.section.4.4.p.3">Unlike <a href="#header.authorization" class="smpl">Authorization</a>, the Proxy-Authorization header field applies only to the next inbound proxy that demanded authentication using the <a href="#header.proxy-authenticate" class="smpl">Proxy-Authenticate</a> field. When multiple proxies are used in a chain, the Proxy-Authorization header field is consumed by the first inbound proxy
815               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
816               authenticate a given request.
817            </p>
818         </div>
819      </div>
820      <div id="IANA.considerations">
821         <h1 id="rfc.section.5"><a href="#rfc.section.5">5.</a>&nbsp;<a href="#IANA.considerations">IANA Considerations</a></h1>
822         <div id="authentication.scheme.registry">
823            <h2 id="rfc.section.5.1"><a href="#rfc.section.5.1">5.1</a>&nbsp;<a href="#authentication.scheme.registry">Authentication Scheme Registry</a></h2>
824            <p id="rfc.section.5.1.p.1">The HTTP Authentication Scheme Registry defines the name space for the authentication schemes in challenges and credentials.
825               It will be created and maintained at (the suggested URI) &lt;<a href="http://www.iana.org/assignments/http-authschemes">http://www.iana.org/assignments/http-authschemes</a>&gt;.
826            </p>
827            <div id="authentication.scheme.registry.procedure">
828               <h3 id="rfc.section.5.1.1"><a href="#rfc.section.5.1.1">5.1.1</a>&nbsp;<a href="#authentication.scheme.registry.procedure">Procedure</a></h3>
829               <p id="rfc.section.5.1.1.p.1">Registrations <em class="bcp14">MUST</em> include the following fields:
830               </p>
831               <ul>
832                  <li>Authentication Scheme Name</li>
833                  <li>Pointer to specification text</li>
834                  <li>Notes (optional)</li>
835               </ul>
836               <p id="rfc.section.5.1.1.p.2">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="http://tools.ietf.org/html/rfc5226#section-4.1">Section 4.1</a>).
837               </p>
838            </div>
839            <div id="considerations.for.new.authentication.schemes">
840               <h3 id="rfc.section.5.1.2"><a href="#rfc.section.5.1.2">5.1.2</a>&nbsp;<a href="#considerations.for.new.authentication.schemes">Considerations for New Authentication Schemes</a></h3>
841               <p id="rfc.section.5.1.2.p.1">There are certain aspects of the HTTP Authentication Framework that put constraints on how new authentication schemes can
842                  work:
843               </p>
844               <p id="rfc.section.5.1.2.p.2"></p>
845               <ul>
846                  <li>
847                     <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
848                        bound to, the underlying connection is outside the scope of this specification and inherently flawed unless steps are taken
849                        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.Part1.6"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a>).
850                     </p>
851                  </li>
852                  <li>
853                     <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.
854                     </p>
855                  </li>
856                  <li>
857                     <p>The "token68" notation was introduced for compatibility with existing authentication schemes and can only be used once per
858                        challenge or credential. New schemes thus ought to use the "auth-param" syntax instead, because otherwise future extensions
859                        will be impossible.
860                     </p>
861                  </li>
862                  <li>
863                     <p>The parsing of challenges and credentials is defined by this specification, and cannot be modified by new authentication schemes.
864                        When the auth-param syntax is used, all parameters ought to support both token and quoted-string syntax, and syntactical constraints
865                        ought to be defined on the field value after parsing (i.e., quoted-string processing). This is necessary so that recipients
866                        can use a generic parser that applies to all authentication schemes.
867                     </p>
868                     <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
869                        repeated for new parameters.
870                     </p>
871                  </li>
872                  <li>
873                     <p>Definitions of new schemes ought to define the treatment of unknown extension parameters. In general, a "must-ignore" rule
874                        is preferable over "must-understand", because otherwise it will be hard to introduce new parameters in the presence of legacy
875                        recipients. Furthermore, it's good to describe the policy for defining new parameters (such as "update the specification",
876                        or "use this registry").
877                     </p>
878                  </li>
879                  <li>
880                     <p>Authentication schemes need to document whether they are usable in origin-server authentication (i.e., using <a href="#header.www-authenticate" class="smpl">WWW-Authenticate</a>), and/or proxy authentication (i.e., using <a href="#header.proxy-authenticate" class="smpl">Proxy-Authenticate</a>).
881                     </p>
882                  </li>
883                  <li>
884                     <p>The credentials carried in an <a href="#header.authorization" class="smpl">Authorization</a> header field are specific to the User Agent, and therefore have the same effect on HTTP caches as the "private" Cache-Control
885                        response directive (<a href="p6-cache.html#cache-response-directive.private" title="private">Section 5.2.2.6</a> of <a href="#Part6" id="rfc.xref.Part6.2"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Caching">[Part6]</cite></a>), within the scope of the request they appear in.
886                     </p>
887                     <p>Therefore, new authentication schemes that choose not to carry credentials in the <a href="#header.authorization" class="smpl">Authorization</a> header field (e.g., using a newly defined header field) will need to explicitly disallow caching, by mandating the use of
888                        either Cache-Control request directives (e.g., "no-store", <a href="p6-cache.html#cache-request-directive.no-store" title="no-store">Section 5.2.1.5</a> of <a href="#Part6" id="rfc.xref.Part6.3"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Caching">[Part6]</cite></a>) or response directives (e.g., "private").
889                     </p>
890                  </li>
891               </ul>
892            </div>
893         </div>
894         <div id="status.code.registration">
895            <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>
896            <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:
897            </p>
898            <div id="rfc.table.1">
899               <div id="iana.status.code.registration.table"></div>
900               <table class="tt full left" cellpadding="3" cellspacing="0">
901                  <thead>
902                     <tr>
903                        <th>Value</th>
904                        <th>Description</th>
905                        <th>Reference</th>
906                     </tr>
907                  </thead>
908                  <tbody>
909                     <tr>
910                        <td class="left">401</td>
911                        <td class="left">Unauthorized</td>
912                        <td class="left"><a href="#status.401" id="rfc.xref.status.401.1" title="401 Unauthorized">Section&nbsp;3.1</a>
913                        </td>
914                     </tr>
915                     <tr>
916                        <td class="left">407</td>
917                        <td class="left">Proxy Authentication Required</td>
918                        <td class="left"><a href="#status.407" id="rfc.xref.status.407.1" title="407 Proxy Authentication Required">Section&nbsp;3.2</a>
919                        </td>
920                     </tr>
921                  </tbody>
922               </table>
923            </div>
924         </div>
925         <div id="header.field.registration">
926            <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>
927            <p id="rfc.section.5.3.p.1">HTTP header fields are registered within the Message Header Field Registry maintained 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;.
928            </p>
929            <p id="rfc.section.5.3.p.2">This document defines the following HTTP header fields, so their associated registry entries shall be updated according to
930               the permanent registrations below (see <a href="#BCP90" id="rfc.xref.BCP90.1"><cite title="Registration Procedures for Message Header Fields">[BCP90]</cite></a>):
931            </p>
932            <div id="rfc.table.2">
933               <div id="iana.header.registration.table"></div>
934               <table class="tt full left" cellpadding="3" cellspacing="0">
935                  <thead>
936                     <tr>
937                        <th>Header Field Name</th>
938                        <th>Protocol</th>
939                        <th>Status</th>
940                        <th>Reference</th>
941                     </tr>
942                  </thead>
943                  <tbody>
944                     <tr>
945                        <td class="left">Authorization</td>
946                        <td class="left">http</td>
947                        <td class="left">standard</td>
948                        <td class="left"><a href="#header.authorization" id="rfc.xref.header.authorization.2" title="Authorization">Section&nbsp;4.2</a>
949                        </td>
950                     </tr>
951                     <tr>
952                        <td class="left">Proxy-Authenticate</td>
953                        <td class="left">http</td>
954                        <td class="left">standard</td>
955                        <td class="left"><a href="#header.proxy-authenticate" id="rfc.xref.header.proxy-authenticate.2" title="Proxy-Authenticate">Section&nbsp;4.3</a>
956                        </td>
957                     </tr>
958                     <tr>
959                        <td class="left">Proxy-Authorization</td>
960                        <td class="left">http</td>
961                        <td class="left">standard</td>
962                        <td class="left"><a href="#header.proxy-authorization" id="rfc.xref.header.proxy-authorization.2" title="Proxy-Authorization">Section&nbsp;4.4</a>
963                        </td>
964                     </tr>
965                     <tr>
966                        <td class="left">WWW-Authenticate</td>
967                        <td class="left">http</td>
968                        <td class="left">standard</td>
969                        <td class="left"><a href="#header.www-authenticate" id="rfc.xref.header.www-authenticate.3" title="WWW-Authenticate">Section&nbsp;4.1</a>
970                        </td>
971                     </tr>
972                  </tbody>
973               </table>
974            </div>
975            <p id="rfc.section.5.3.p.3">The change controller is: "IETF (iesg@ietf.org) - Internet Engineering Task Force".</p>
976         </div>
977      </div>
978      <div id="security.considerations">
979         <h1 id="rfc.section.6"><a href="#rfc.section.6">6.</a>&nbsp;<a href="#security.considerations">Security Considerations</a></h1>
980         <p id="rfc.section.6.p.1">This section is meant to inform developers, information providers, and users of known security concerns specific to HTTP authentication.
981            More general security considerations are addressed in HTTP messaging <a href="#Part1" id="rfc.xref.Part1.7"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a> and semantics <a href="#Part2" id="rfc.xref.Part2.2"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content">[Part2]</cite></a>.
982         </p>
983         <p id="rfc.section.6.p.2">Everything about the topic of HTTP authentication is a security consideration, so the list of considerations below is not
984            exhaustive. Furthermore, it is limited to security considerations regarding the authentication framework, in general, rather
985            than discussing all of the potential considerations for specific authentication schemes (which ought to be documented in the
986            specifications that define those schemes). Various organizations maintain topical information and links to current research
987            on Web application security (e.g., <a href="#OWASP" id="rfc.xref.OWASP.1"><cite title="A Guide to Building Secure Web Applications and Web Services">[OWASP]</cite></a>), including common pitfalls for implementing and using the authentication schemes found in practice.
988         </p>
989         <div id="confidentiality.of.credentials">
990            <h2 id="rfc.section.6.1"><a href="#rfc.section.6.1">6.1</a>&nbsp;<a href="#confidentiality.of.credentials">Confidentiality of Credentials</a></h2>
991            <p id="rfc.section.6.1.p.1">The HTTP authentication framework does not define a single mechanism for maintaining the confidentiality of credentials; instead,
992               each authentication scheme defines how the credentials are encoded prior to transmission. While this provides flexibility
993               for the development of future authentication schemes, it is inadequate for the protection of existing schemes that provide
994               no confidentiality on their own, or that do not sufficiently protect against replay attacks. Furthermore, if the server expects
995               credentials that are specific to each individual user, the exchange of those credentials will have the effect of identifying
996               that user even if the content within credentials remains confidential.
997            </p>
998            <p id="rfc.section.6.1.p.2">HTTP depends on the security properties of the underlying transport or session-level connection to provide confidential transmission
999               of header fields. In other words, if a server limits access to authenticated users using this framework, the server needs
1000               to ensure that the connection is properly secured in accordance with the nature of the authentication scheme used. For example,
1001               services that depend on individual user authentication often require a connection to be secured with TLS ("Transport Layer
1002               Security", <a href="#RFC5246" id="rfc.xref.RFC5246.1"><cite title="The Transport Layer Security (TLS) Protocol Version 1.2">[RFC5246]</cite></a>) prior to exchanging any credentials.
1003            </p>
1004         </div>
1005         <div id="auth.credentials.and.idle.clients">
1006            <h2 id="rfc.section.6.2"><a href="#rfc.section.6.2">6.2</a>&nbsp;<a href="#auth.credentials.and.idle.clients">Authentication Credentials and Idle Clients</a></h2>
1007            <p id="rfc.section.6.2.p.1">Existing HTTP clients and user agents typically retain authentication information indefinitely. HTTP does not provide a mechanism
1008               for the origin server to direct clients to discard these cached credentials, since the protocol has no awareness of how credentials
1009               are obtained or managed by the user agent. The mechanisms for expiring or revoking credentials can be specified as part of
1010               an authentication scheme definition.
1011            </p>
1012            <p id="rfc.section.6.2.p.2">Circumstances under which credential caching can interfere with the application's security model include but are not limited
1013               to:
1014            </p>
1015            <ul>
1016               <li>Clients that have been idle for an extended period, following which the server might wish to cause the client to re-prompt
1017                  the user for credentials.
1018               </li>
1019               <li>Applications that include a session termination indication (such as a "logout" or "commit" button on a page) after which the
1020                  server side of the application "knows" that there is no further reason for the client to retain the credentials.
1021               </li>
1022            </ul>
1023            <p id="rfc.section.6.2.p.3">User agents that cache credentials are encouraged to provide a readily accessible mechanism for discarding cached credentials
1024               under user control.
1025            </p>
1026         </div>
1027         <div id="protection.spaces">
1028            <h2 id="rfc.section.6.3"><a href="#rfc.section.6.3">6.3</a>&nbsp;<a href="#protection.spaces">Protection Spaces</a></h2>
1029            <p id="rfc.section.6.3.p.1">Authentication schemes that solely rely on the "realm" mechanism for establishing a protection space will expose credentials
1030               to all resources on an origin server. Clients that have successfully made authenticated requests with a resource can use the
1031               same authentication credentials for other resources on the same origin server. This makes it possible for a different resource
1032               to harvest authentication credentials for other resources.
1033            </p>
1034            <p id="rfc.section.6.3.p.2">This is of particular concern when an origin server hosts resources for multiple parties under the same canonical root URI
1035               (<a href="#protection.space" title="Protection Space (Realm)">Section&nbsp;2.2</a>). Possible mitigation strategies include restricting direct access to authentication credentials (i.e., not making the content
1036               of the <a href="#header.authorization" class="smpl">Authorization</a> request header field available), and separating protection spaces by using a different host name (or port number) for each
1037               party.
1038            </p>
1039         </div>
1040      </div>
1041      <div id="acks">
1042         <h1 id="rfc.section.7"><a href="#rfc.section.7">7.</a>&nbsp;<a href="#acks">Acknowledgments</a></h1>
1043         <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
1044            Lawrence C. Stewart for their work on that specification. See <a href="http://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.
1045         </p>
1046         <p id="rfc.section.7.p.2">See <a href="p1-messaging.html#acks" title="Acknowledgments">Section 10</a> of <a href="#Part1" id="rfc.xref.Part1.8"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a> for the Acknowledgments related to this document revision.
1047         </p>
1048      </div>
1049      <h1 id="rfc.references"><a id="rfc.section.8" href="#rfc.section.8">8.</a> References
1050      </h1>
1051      <h2 id="rfc.references.1"><a href="#rfc.section.8.1" id="rfc.section.8.1">8.1</a> Normative References
1052      </h2>
1053      <table>
1054         <tr>
1055            <td class="reference"><b id="Part1">[Part1]</b></td>
1056            <td class="top"><a href="mailto:fielding@gbiv.com" title="Adobe Systems Incorporated">Fielding, R., Ed.</a> and <a href="mailto:julian.reschke@greenbytes.de" title="greenbytes GmbH">J. Reschke, Ed.</a>, “<a href="http://tools.ietf.org/html/draft-ietf-httpbis-p1-messaging-latest">Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing</a>”, Internet-Draft&nbsp;draft-ietf-httpbis-p1-messaging-latest (work in progress), January&nbsp;2014.
1057            </td>
1058         </tr>
1059         <tr>
1060            <td class="reference"><b id="Part2">[Part2]</b></td>
1061            <td class="top"><a href="mailto:fielding@gbiv.com" title="Adobe Systems Incorporated">Fielding, R., Ed.</a> and <a href="mailto:julian.reschke@greenbytes.de" title="greenbytes GmbH">J. Reschke, Ed.</a>, “<a href="http://tools.ietf.org/html/draft-ietf-httpbis-p2-semantics-latest">Hypertext Transfer Protocol (HTTP/1.1): Semantics and Content</a>”, Internet-Draft&nbsp;draft-ietf-httpbis-p2-semantics-latest (work in progress), January&nbsp;2014.
1062            </td>
1063         </tr>
1064         <tr>
1065            <td class="reference"><b id="Part6">[Part6]</b></td>
1066            <td class="top"><a href="mailto:fielding@gbiv.com" title="Adobe Systems Incorporated">Fielding, R., Ed.</a>, <a href="mailto:mnot@mnot.net" title="Akamai">Nottingham, M., Ed.</a>, and <a href="mailto:julian.reschke@greenbytes.de" title="greenbytes GmbH">J. Reschke, Ed.</a>, “<a href="http://tools.ietf.org/html/draft-ietf-httpbis-p6-cache-latest">Hypertext Transfer Protocol (HTTP/1.1): Caching</a>”, Internet-Draft&nbsp;draft-ietf-httpbis-p6-cache-latest (work in progress), January&nbsp;2014.
1067            </td>
1068         </tr>
1069         <tr>
1070            <td class="reference"><b id="RFC2119">[RFC2119]</b></td>
1071            <td class="top"><a href="mailto:sob@harvard.edu" title="Harvard University">Bradner, S.</a>, “<a href="http://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.
1072            </td>
1073         </tr>
1074         <tr>
1075            <td class="reference"><b id="RFC5234">[RFC5234]</b></td>
1076            <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="http://tools.ietf.org/html/rfc5234">Augmented BNF for Syntax Specifications: ABNF</a>”, STD&nbsp;68, RFC&nbsp;5234, January&nbsp;2008.
1077            </td>
1078         </tr>
1079      </table>
1080      <h2 id="rfc.references.2"><a href="#rfc.section.8.2" id="rfc.section.8.2">8.2</a> Informative References
1081      </h2>
1082      <table>
1083         <tr>
1084            <td class="reference"><b id="BCP90">[BCP90]</b></td>
1085            <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="http://tools.ietf.org/html/rfc3864">Registration Procedures for Message Header Fields</a>”, BCP&nbsp;90, RFC&nbsp;3864, September&nbsp;2004.
1086            </td>
1087         </tr>
1088         <tr>
1089            <td class="reference"><b id="OWASP">[OWASP]</b></td>
1090            <td class="top">van der Stock, A., Ed., “<a href="https://www.owasp.org/">A Guide to Building Secure Web Applications and Web Services</a>”, The Open Web Application Security Project (OWASP)&nbsp;2.0.1, July&nbsp;2005, &lt;<a href="https://www.owasp.org/">https://www.owasp.org/</a>&gt;.
1091            </td>
1092         </tr>
1093         <tr>
1094            <td class="reference"><b id="RFC2616">[RFC2616]</b></td>
1095            <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="http://tools.ietf.org/html/rfc2616">Hypertext Transfer Protocol -- HTTP/1.1</a>”, RFC&nbsp;2616, June&nbsp;1999.
1096            </td>
1097         </tr>
1098         <tr>
1099            <td class="reference"><b id="RFC2617">[RFC2617]</b></td>
1100            <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="http://tools.ietf.org/html/rfc2617">HTTP Authentication: Basic and Digest Access Authentication</a>”, RFC&nbsp;2617, June&nbsp;1999.
1101            </td>
1102         </tr>
1103         <tr>
1104            <td class="reference"><b id="RFC3986">[RFC3986]</b></td>
1105            <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="http://tools.ietf.org/html/rfc3986">Uniform Resource Identifier (URI): Generic Syntax</a>”, STD&nbsp;66, RFC&nbsp;3986, January&nbsp;2005.
1106            </td>
1107         </tr>
1108         <tr>
1109            <td class="reference"><b id="RFC4648">[RFC4648]</b></td>
1110            <td class="top">Josefsson, S., “<a href="http://tools.ietf.org/html/rfc4648">The Base16, Base32, and Base64 Data Encodings</a>”, RFC&nbsp;4648, October&nbsp;2006.
1111            </td>
1112         </tr>
1113         <tr>
1114            <td class="reference"><b id="RFC5226">[RFC5226]</b></td>
1115            <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="http://tools.ietf.org/html/rfc5226">Guidelines for Writing an IANA Considerations Section in RFCs</a>”, BCP&nbsp;26, RFC&nbsp;5226, May&nbsp;2008.
1116            </td>
1117         </tr>
1118         <tr>
1119            <td class="reference"><b id="RFC5246">[RFC5246]</b></td>
1120            <td class="top">Dierks, T. and E. Rescorla, “<a href="http://tools.ietf.org/html/rfc5246">The Transport Layer Security (TLS) Protocol Version 1.2</a>”, RFC&nbsp;5246, August&nbsp;2008.
1121            </td>
1122         </tr>
1123      </table>
1124      <div class="avoidbreak">
1125         <h1 id="rfc.authors"><a href="#rfc.authors">Authors' Addresses</a></h1>
1126         <p><b>Roy T. Fielding</b>
1127            (editor)
1128            <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>
1129         <p><b>Julian F. Reschke</b>
1130            (editor)
1131            <br>greenbytes GmbH<br>Hafenweg 16<br>Muenster, NW&nbsp;48155<br>Germany<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>
1132      </div>
1133      <div id="changes.from.rfc.2616">
1134         <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>
1135         <p id="rfc.section.A.p.1">The framework for HTTP Authentication is now defined by this document, rather than RFC 2617.</p>
1136         <p id="rfc.section.A.p.2">The "realm" parameter is no longer always required on challenges; consequently, the ABNF allows challenges without any auth
1137            parameters. (<a href="#access.authentication.framework" title="Access Authentication Framework">Section&nbsp;2</a>)
1138         </p>
1139         <p id="rfc.section.A.p.3">The "token68" alternative to auth-param lists has been added for consistency with legacy authentication schemes such as "Basic".
1140            (<a href="#access.authentication.framework" title="Access Authentication Framework">Section&nbsp;2</a>)
1141         </p>
1142         <p id="rfc.section.A.p.4">This specification introduces the Authentication Scheme Registry, along with considerations for new authentication schemes.
1143            (<a href="#authentication.scheme.registry" title="Authentication Scheme Registry">Section&nbsp;5.1</a>)
1144         </p>
1145      </div>
1146      <div id="imported.abnf">
1147         <h1 id="rfc.section.B"><a href="#rfc.section.B">B.</a>&nbsp;<a href="#imported.abnf">Imported ABNF</a></h1>
1148         <p id="rfc.section.B.p.1">The following core rules are included by reference, as defined in <a href="http://tools.ietf.org/html/rfc5234#appendix-B.1">Appendix B.1</a> of <a href="#RFC5234" id="rfc.xref.RFC5234.2"><cite title="Augmented BNF for Syntax Specifications: ABNF">[RFC5234]</cite></a>: ALPHA (letters), CR (carriage return), CRLF (CR LF), CTL (controls), DIGIT (decimal 0-9), DQUOTE (double quote), HEXDIG
1149            (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
1150            character).
1151         </p>
1152         <p id="rfc.section.B.p.2">The rules below are defined in <a href="#Part1" id="rfc.xref.Part1.9"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a>:
1153         </p>
1154         <div id="rfc.figure.u.9"></div><pre class="inline">  <a href="#imported.abnf" class="smpl">BWS</a>           = &lt;BWS, defined in <a href="#Part1" id="rfc.xref.Part1.10"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.3</a>&gt;
1155  <a href="#imported.abnf" class="smpl">OWS</a>           = &lt;OWS, defined in <a href="#Part1" id="rfc.xref.Part1.11"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a>, <a href="p1-messaging.html#whitespace" title="Whitespace">Section 3.2.3</a>&gt;
1156  <a href="#imported.abnf" class="smpl">quoted-string</a> = &lt;quoted-string, defined in <a href="#Part1" id="rfc.xref.Part1.12"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.6</a>&gt;
1157  <a href="#imported.abnf" class="smpl">token</a>         = &lt;token, defined in <a href="#Part1" id="rfc.xref.Part1.13"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a>, <a href="p1-messaging.html#field.components" title="Field value components">Section 3.2.6</a>&gt;
1158</pre></div>
1159      <div id="collected.abnf">
1160         <h1 id="rfc.section.C"><a href="#rfc.section.C">C.</a>&nbsp;<a href="#collected.abnf">Collected ABNF</a></h1>
1161         <p id="rfc.section.C.p.1">In the collected ABNF below, list rules are expanded as per <a href="p1-messaging.html#notation" title="Syntax Notation">Section 1.2</a> of <a href="#Part1" id="rfc.xref.Part1.14"><cite title="Hypertext Transfer Protocol (HTTP/1.1): Message Syntax and Routing">[Part1]</cite></a>.
1162         </p>
1163         <div id="rfc.figure.u.10"></div><pre class="inline"><a href="#header.authorization" class="smpl">Authorization</a> = credentials
1164
1165<a href="#imported.abnf" class="smpl">BWS</a> = &lt;BWS, defined in [Part1], Section 3.2.3&gt;
1166
1167<a href="#imported.abnf" class="smpl">OWS</a> = &lt;OWS, defined in [Part1], Section 3.2.3&gt;
1168
1169<a href="#header.proxy-authenticate" class="smpl">Proxy-Authenticate</a> = *( "," OWS ) challenge *( OWS "," [ OWS
1170 challenge ] )
1171<a href="#header.proxy-authorization" class="smpl">Proxy-Authorization</a> = credentials
1172
1173<a href="#header.www-authenticate" class="smpl">WWW-Authenticate</a> = *( "," OWS ) challenge *( OWS "," [ OWS challenge
1174 ] )
1175
1176<a href="#challenge.and.response" class="smpl">auth-param</a> = token BWS "=" BWS ( token / quoted-string )
1177<a href="#challenge.and.response" class="smpl">auth-scheme</a> = token
1178
1179<a href="#challenge.and.response" class="smpl">challenge</a> = auth-scheme [ 1*SP ( token68 / [ ( "," / auth-param ) *(
1180 OWS "," [ OWS auth-param ] ) ] ) ]
1181<a href="#challenge.and.response" class="smpl">credentials</a> = auth-scheme [ 1*SP ( token68 / [ ( "," / auth-param )
1182 *( OWS "," [ OWS auth-param ] ) ] ) ]
1183
1184<a href="#imported.abnf" class="smpl">quoted-string</a> = &lt;quoted-string, defined in [Part1], Section 3.2.6&gt;
1185
1186<a href="#imported.abnf" class="smpl">token</a> = &lt;token, defined in [Part1], Section 3.2.6&gt;
1187<a href="#challenge.and.response" class="smpl">token68</a> = 1*( ALPHA / DIGIT / "-" / "." / "_" / "~" / "+" / "/" )
1188 *"="
1189</pre></div>
1190      <div id="change.log">
1191         <h1 id="rfc.section.D"><a href="#rfc.section.D">D.</a>&nbsp;<a href="#change.log">Change Log (to be removed by RFC Editor before publication)</a></h1>
1192         <p id="rfc.section.D.p.1">Changes up to the IETF Last Call draft are summarized in &lt;<a href="http://trac.tools.ietf.org/html/draft-ietf-httpbis-p7-auth-24#appendix-D">http://trac.tools.ietf.org/html/draft-ietf-httpbis-p7-auth-24#appendix-D</a>&gt;.
1193         </p>
1194         <div id="changes.since.24">
1195            <h2 id="rfc.section.D.1"><a href="#rfc.section.D.1">D.1</a>&nbsp;<a href="#changes.since.24">Since draft-ietf-httpbis-p7-auth-24</a></h2>
1196            <p id="rfc.section.D.1.p.1">Closed issues: </p>
1197            <ul>
1198               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/510">http://tools.ietf.org/wg/httpbis/trac/ticket/510</a>&gt;: "SECDIR review of draft-ietf-httpbis-p7-auth-24"
1199               </li>
1200               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/513">http://tools.ietf.org/wg/httpbis/trac/ticket/513</a>&gt;: "APPSDIR review of draft-ietf-httpbis-p7-auth-24"
1201               </li>
1202               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/516">http://tools.ietf.org/wg/httpbis/trac/ticket/516</a>&gt;: "note about WWW-A parsing potentially misleading"
1203               </li>
1204            </ul>
1205         </div>
1206         <div id="changes.since.25">
1207            <h2 id="rfc.section.D.2"><a href="#rfc.section.D.2">D.2</a>&nbsp;<a href="#changes.since.25">Since draft-ietf-httpbis-p7-auth-25</a></h2>
1208            <p id="rfc.section.D.2.p.1">Closed issues: </p>
1209            <ul>
1210               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/522">http://tools.ietf.org/wg/httpbis/trac/ticket/522</a>&gt;: "Gen-art review of draft-ietf-httpbis-p7-auth-25"
1211               </li>
1212               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/536">http://tools.ietf.org/wg/httpbis/trac/ticket/536</a>&gt;: "IESG ballot on draft-ietf-httpbis-p7-auth-25"
1213               </li>
1214               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/538">http://tools.ietf.org/wg/httpbis/trac/ticket/538</a>&gt;: "add 'stateless' to Abstract"
1215               </li>
1216               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/539">http://tools.ietf.org/wg/httpbis/trac/ticket/539</a>&gt;: "mention TLS vs plain text passwords or dict attacks?"
1217               </li>
1218               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/542">http://tools.ietf.org/wg/httpbis/trac/ticket/542</a>&gt;: "improve introduction of list rule"
1219               </li>
1220               <li>&lt;<a href="http://tools.ietf.org/wg/httpbis/trac/ticket/549">http://tools.ietf.org/wg/httpbis/trac/ticket/549</a>&gt;: "augment security considerations with pointers to current research"
1221               </li>
1222            </ul>
1223         </div>
1224      </div>
1225      <h1 id="rfc.index"><a href="#rfc.index">Index</a></h1>
1226      <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.O">O</a> <a href="#rfc.index.P">P</a> <a href="#rfc.index.R">R</a> <a href="#rfc.index.W">W</a>
1227      </p>
1228      <div class="print2col">
1229         <ul class="ind">
1230            <li><a id="rfc.index.4" href="#rfc.index.4"><b>4</b></a><ul>
1231                  <li>401 Unauthorized (status code)&nbsp;&nbsp;<a href="#rfc.iref.8"><b>3.1</b></a>, <a href="#rfc.xref.status.401.1">5.2</a></li>
1232                  <li>407 Proxy Authentication Required (status code)&nbsp;&nbsp;<a href="#rfc.iref.8"><b>3.2</b></a>, <a href="#rfc.xref.status.407.1">5.2</a></li>
1233               </ul>
1234            </li>
1235            <li><a id="rfc.index.A" href="#rfc.index.A"><b>A</b></a><ul>
1236                  <li>Authorization header field&nbsp;&nbsp;<a href="#rfc.xref.header.authorization.1">3.1</a>, <a href="#rfc.iref.a.1"><b>4.2</b></a>, <a href="#rfc.xref.header.authorization.2">5.3</a></li>
1237               </ul>
1238            </li>
1239            <li><a id="rfc.index.B" href="#rfc.index.B"><b>B</b></a><ul>
1240                  <li><em>BCP90</em>&nbsp;&nbsp;<a href="#rfc.xref.BCP90.1">5.3</a>, <a href="#BCP90"><b>8.2</b></a></li>
1241               </ul>
1242            </li>
1243            <li><a id="rfc.index.C" href="#rfc.index.C"><b>C</b></a><ul>
1244                  <li>Canonical Root URI&nbsp;&nbsp;<a href="#rfc.iref.c.1">2.2</a></li>
1245               </ul>
1246            </li>
1247            <li><a id="rfc.index.G" href="#rfc.index.G"><b>G</b></a><ul>
1248                  <li><tt>Grammar</tt>&nbsp;&nbsp;
1249                     <ul>
1250                        <li><tt>auth-param</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.2"><b>2.1</b></a></li>
1251                        <li><tt>auth-scheme</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.1"><b>2.1</b></a></li>
1252                        <li><tt>Authorization</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.7"><b>4.2</b></a></li>
1253                        <li><tt>challenge</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.4"><b>2.1</b></a></li>
1254                        <li><tt>credentials</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.5"><b>2.1</b></a></li>
1255                        <li><tt>Proxy-Authenticate</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.8"><b>4.3</b></a></li>
1256                        <li><tt>Proxy-Authorization</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.9"><b>4.4</b></a></li>
1257                        <li><tt>token68</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.3"><b>2.1</b></a></li>
1258                        <li><tt>WWW-Authenticate</tt>&nbsp;&nbsp;<a href="#rfc.iref.g.6"><b>4.1</b></a></li>
1259                     </ul>
1260                  </li>
1261               </ul>
1262            </li>
1263            <li><a id="rfc.index.O" href="#rfc.index.O"><b>O</b></a><ul>
1264                  <li><em>OWASP</em>&nbsp;&nbsp;<a href="#rfc.xref.OWASP.1">6</a>, <a href="#OWASP"><b>8.2</b></a></li>
1265               </ul>
1266            </li>
1267            <li><a id="rfc.index.P" href="#rfc.index.P"><b>P</b></a><ul>
1268                  <li><em>Part1</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.1">1</a>, <a href="#rfc.xref.Part1.2">1.1</a>, <a href="#rfc.xref.Part1.3">1.2</a>, <a href="#rfc.xref.Part1.4">2.2</a>, <a href="#rfc.xref.Part1.5">4.3</a>, <a href="#rfc.xref.Part1.6">5.1.2</a>, <a href="#rfc.xref.Part1.7">6</a>, <a href="#rfc.xref.Part1.8">7</a>, <a href="#Part1"><b>8.1</b></a>, <a href="#rfc.xref.Part1.9">B</a>, <a href="#rfc.xref.Part1.10">B</a>, <a href="#rfc.xref.Part1.11">B</a>, <a href="#rfc.xref.Part1.12">B</a>, <a href="#rfc.xref.Part1.13">B</a>, <a href="#rfc.xref.Part1.14">C</a><ul>
1269                        <li><em>Section 1.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.14">C</a></li>
1270                        <li><em>Section 2.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.6">5.1.2</a></li>
1271                        <li><em>Section 2.5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.2">1.1</a></li>
1272                        <li><em>Section 3.2.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.10">B</a>, <a href="#rfc.xref.Part1.11">B</a></li>
1273                        <li><em>Section 3.2.6</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.12">B</a>, <a href="#rfc.xref.Part1.13">B</a></li>
1274                        <li><em>Section 5.5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.4">2.2</a>, <a href="#rfc.xref.Part1.5">4.3</a></li>
1275                        <li><em>Section 7</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.3">1.2</a></li>
1276                        <li><em>Section 10</em>&nbsp;&nbsp;<a href="#rfc.xref.Part1.8">7</a></li>
1277                     </ul>
1278                  </li>
1279                  <li><em>Part2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.1">2.1</a>, <a href="#rfc.xref.Part2.2">6</a>, <a href="#Part2"><b>8.1</b></a><ul>
1280                        <li><em>Section 6.5.3</em>&nbsp;&nbsp;<a href="#rfc.xref.Part2.1">2.1</a></li>
1281                     </ul>
1282                  </li>
1283                  <li><em>Part6</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.1">4.2</a>, <a href="#rfc.xref.Part6.2">5.1.2</a>, <a href="#rfc.xref.Part6.3">5.1.2</a>, <a href="#Part6"><b>8.1</b></a><ul>
1284                        <li><em>Section 3.2</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.1">4.2</a></li>
1285                        <li><em>Section 5.2.1.5</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.3">5.1.2</a></li>
1286                        <li><em>Section 5.2.2.6</em>&nbsp;&nbsp;<a href="#rfc.xref.Part6.2">5.1.2</a></li>
1287                     </ul>
1288                  </li>
1289                  <li>Protection Space&nbsp;&nbsp;<a href="#rfc.iref.p.1">2.2</a></li>
1290                  <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>4.3</b></a>, <a href="#rfc.xref.header.proxy-authenticate.2">5.3</a></li>
1291                  <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>4.4</b></a>, <a href="#rfc.xref.header.proxy-authorization.2">5.3</a></li>
1292               </ul>
1293            </li>
1294            <li><a id="rfc.index.R" href="#rfc.index.R"><b>R</b></a><ul>
1295                  <li>Realm&nbsp;&nbsp;<a href="#rfc.iref.r.1">2.2</a></li>
1296                  <li><em>RFC2119</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2119.1">1.1</a>, <a href="#RFC2119"><b>8.1</b></a></li>
1297                  <li><em>RFC2616</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2616.1">1</a>, <a href="#RFC2616"><b>8.2</b></a></li>
1298                  <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>
1299                        <li><em>Section 6</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC2617.4">7</a></li>
1300                     </ul>
1301                  </li>
1302                  <li><em>RFC3986</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC3986.1">2.1</a>, <a href="#RFC3986"><b>8.2</b></a></li>
1303                  <li><em>RFC4648</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC4648.1">2.1</a>, <a href="#RFC4648"><b>8.2</b></a></li>
1304                  <li><em>RFC5226</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5226.1">5.1.1</a>, <a href="#RFC5226"><b>8.2</b></a><ul>
1305                        <li><em>Section 4.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5226.1">5.1.1</a></li>
1306                     </ul>
1307                  </li>
1308                  <li><em>RFC5234</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5234.1">1.2</a>, <a href="#RFC5234"><b>8.1</b></a>, <a href="#rfc.xref.RFC5234.2">B</a><ul>
1309                        <li><em>Appendix B.1</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5234.2">B</a></li>
1310                     </ul>
1311                  </li>
1312                  <li><em>RFC5246</em>&nbsp;&nbsp;<a href="#rfc.xref.RFC5246.1">6.1</a>, <a href="#RFC5246"><b>8.2</b></a></li>
1313               </ul>
1314            </li>
1315            <li><a id="rfc.index.W" href="#rfc.index.W"><b>W</b></a><ul>
1316                  <li>WWW-Authenticate header field&nbsp;&nbsp;<a href="#rfc.xref.header.www-authenticate.1">3.1</a>, <a href="#rfc.iref.w.1"><b>4.1</b></a>, <a href="#rfc.xref.header.www-authenticate.2">4.3</a>, <a href="#rfc.xref.header.www-authenticate.3">5.3</a></li>
1317               </ul>
1318            </li>
1319         </ul>
1320      </div>
1321   </body>
1322</html>
Note: See TracBrowser for help on using the repository browser.