draft-ietf-httpbis-p7-auth-04.txt   draft-ietf-httpbis-p7-auth-05.txt 
Network Working Group R. Fielding, Ed. Network Working Group R. Fielding, Ed.
Internet-Draft Day Software Internet-Draft Day Software
Obsoletes: 2616 (if approved) J. Gettys Obsoletes: 2616 (if approved) J. Gettys
Updates: 2617 (if approved) One Laptop per Child Updates: 2617 (if approved) One Laptop per Child
Intended status: Standards Track J. Mogul Intended status: Standards Track J. Mogul
Expires: March 2, 2009 HP Expires: May 20, 2009 HP
H. Frystyk H. Frystyk
Microsoft Microsoft
L. Masinter L. Masinter
Adobe Systems Adobe Systems
P. Leach P. Leach
Microsoft Microsoft
T. Berners-Lee T. Berners-Lee
W3C/MIT W3C/MIT
Y. Lafon, Ed. Y. Lafon, Ed.
W3C W3C
J. Reschke, Ed. J. Reschke, Ed.
greenbytes greenbytes
August 29, 2008 November 16, 2008
HTTP/1.1, part 7: Authentication HTTP/1.1, part 7: Authentication
draft-ietf-httpbis-p7-auth-04 draft-ietf-httpbis-p7-auth-05
Status of this Memo Status of this Memo
By submitting this Internet-Draft, each author represents that any By submitting this Internet-Draft, each author represents that any
applicable patent or other IPR claims of which he or she is aware applicable patent or other IPR claims of which he or she is aware
have been or will be disclosed, and any of which he or she becomes have been or will be disclosed, and any of which he or she becomes
aware will be disclosed, in accordance with Section 6 of BCP 79. aware will be disclosed, in accordance with Section 6 of BCP 79.
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that Task Force (IETF), its areas, and its working groups. Note that
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and may be updated, replaced, or obsoleted by other documents at any and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress." material or to cite them other than as "work in progress."
The list of current Internet-Drafts can be accessed at The list of current Internet-Drafts can be accessed at
http://www.ietf.org/ietf/1id-abstracts.txt. http://www.ietf.org/ietf/1id-abstracts.txt.
The list of Internet-Draft Shadow Directories can be accessed at The list of Internet-Draft Shadow Directories can be accessed at
http://www.ietf.org/shadow.html. http://www.ietf.org/shadow.html.
This Internet-Draft will expire on March 2, 2009. This Internet-Draft will expire on May 20, 2009.
Abstract Abstract
The Hypertext Transfer Protocol (HTTP) is an application-level The Hypertext Transfer Protocol (HTTP) is an application-level
protocol for distributed, collaborative, hypermedia information protocol for distributed, collaborative, hypermedia information
systems. HTTP has been in use by the World Wide Web global systems. HTTP has been in use by the World Wide Web global
information initiative since 1990. This document is Part 7 of the information initiative since 1990. This document is Part 7 of the
seven-part specification that defines the protocol referred to as seven-part specification that defines the protocol referred to as
"HTTP/1.1" and, taken together, obsoletes RFC 2616. Part 7 defines "HTTP/1.1" and, taken together, obsoletes RFC 2616. Part 7 defines
HTTP Authentication. HTTP Authentication.
Editorial Note (To be removed by RFC Editor) Editorial Note (To be removed by RFC Editor)
Discussion of this draft should take place on the HTTPBIS working Discussion of this draft should take place on the HTTPBIS working
group mailing list (ietf-http-wg@w3.org). The current issues list is group mailing list (ietf-http-wg@w3.org). The current issues list is
at <http://www.tools.ietf.org/wg/httpbis/trac/report/11> and related at <http://tools.ietf.org/wg/httpbis/trac/report/11> and related
documents (including fancy diffs) can be found at documents (including fancy diffs) can be found at
<http://www.tools.ietf.org/wg/httpbis/>. <http://tools.ietf.org/wg/httpbis/>.
The changes in this draft are summarized in Appendix B.4. The changes in this draft are summarized in Appendix B.6.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Requirements . . . . . . . . . . . . . . . . . . . . . . . 4 1.1. Requirements . . . . . . . . . . . . . . . . . . . . . . . 4
2. Notational Conventions and Generic Grammar . . . . . . . . . . 4 2. Notational Conventions and Generic Grammar . . . . . . . . . . 4
3. Status Code Definitions . . . . . . . . . . . . . . . . . . . 5 3. Status Code Definitions . . . . . . . . . . . . . . . . . . . 5
3.1. 401 Unauthorized . . . . . . . . . . . . . . . . . . . . . 5 3.1. 401 Unauthorized . . . . . . . . . . . . . . . . . . . . . 5
3.2. 407 Proxy Authentication Required . . . . . . . . . . . . 5 3.2. 407 Proxy Authentication Required . . . . . . . . . . . . 5
4. Header Field Definitions . . . . . . . . . . . . . . . . . . . 5 4. Header Field Definitions . . . . . . . . . . . . . . . . . . . 5
4.1. Authorization . . . . . . . . . . . . . . . . . . . . . . 5 4.1. Authorization . . . . . . . . . . . . . . . . . . . . . . 5
4.2. Proxy-Authenticate . . . . . . . . . . . . . . . . . . . . 6 4.2. Proxy-Authenticate . . . . . . . . . . . . . . . . . . . . 6
4.3. Proxy-Authorization . . . . . . . . . . . . . . . . . . . 7 4.3. Proxy-Authorization . . . . . . . . . . . . . . . . . . . 7
4.4. WWW-Authenticate . . . . . . . . . . . . . . . . . . . . . 7 4.4. WWW-Authenticate . . . . . . . . . . . . . . . . . . . . . 7
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 7
5.1. Message Header Registration . . . . . . . . . . . . . . . 7 5.1. Message Header Registration . . . . . . . . . . . . . . . 8
6. Security Considerations . . . . . . . . . . . . . . . . . . . 8 6. Security Considerations . . . . . . . . . . . . . . . . . . . 8
6.1. Authentication Credentials and Idle Clients . . . . . . . 8 6.1. Authentication Credentials and Idle Clients . . . . . . . 8
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 9 7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 9
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 9 8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 9
8.1. Normative References . . . . . . . . . . . . . . . . . . . 9 8.1. Normative References . . . . . . . . . . . . . . . . . . . 9
8.2. Informative References . . . . . . . . . . . . . . . . . . 9 8.2. Informative References . . . . . . . . . . . . . . . . . . 9
Appendix A. Compatibility with Previous Versions . . . . . . . . 9 Appendix A. Compatibility with Previous Versions . . . . . . . . 10
A.1. Changes from RFC 2616 . . . . . . . . . . . . . . . . . . 9 A.1. Changes from RFC 2616 . . . . . . . . . . . . . . . . . . 10
Appendix B. Change Log (to be removed by RFC Editor before Appendix B. Change Log (to be removed by RFC Editor before
publication) . . . . . . . . . . . . . . . . . . . . 9 publication) . . . . . . . . . . . . . . . . . . . . 10
B.1. Since RFC2616 . . . . . . . . . . . . . . . . . . . . . . 10 B.1. Since RFC2616 . . . . . . . . . . . . . . . . . . . . . . 10
B.2. Since draft-ietf-httpbis-p7-auth-00 . . . . . . . . . . . 10 B.2. Since draft-ietf-httpbis-p7-auth-00 . . . . . . . . . . . 10
B.3. Since draft-ietf-httpbis-p7-auth-01 . . . . . . . . . . . 10 B.3. Since draft-ietf-httpbis-p7-auth-01 . . . . . . . . . . . 10
B.4. Since draft-ietf-httpbis-p7-auth-02 . . . . . . . . . . . 10 B.4. Since draft-ietf-httpbis-p7-auth-02 . . . . . . . . . . . 10
B.5. Since draft-ietf-httpbis-p7-auth-03 . . . . . . . . . . . 10 B.5. Since draft-ietf-httpbis-p7-auth-03 . . . . . . . . . . . 10
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 B.6. Since draft-ietf-httpbis-p7-auth-04 . . . . . . . . . . . 10
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 11 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 11
Intellectual Property and Copyright Statements . . . . . . . . . . 14 Intellectual Property and Copyright Statements . . . . . . . . . . 15
1. Introduction 1. Introduction
This document defines HTTP/1.1 access control and authentication. This document defines HTTP/1.1 access control and authentication.
Right now it includes the extracted relevant sections of RFC 2616 Right now it includes the extracted relevant sections of RFC 2616
with only minor changes. The intention is to move the general with only minor changes. The intention is to move the general
framework for HTTP authentication here, as currently specified in framework for HTTP authentication here, as currently specified in
[RFC2617], and allow the individual authentication mechanisms to be [RFC2617], and allow the individual authentication mechanisms to be
defined elsewhere. This introduction will be rewritten when that defined elsewhere. This introduction will be rewritten when that
occurs. occurs.
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implements. An implementation that satisfies all the MUST or implements. An implementation that satisfies all the MUST or
REQUIRED level and all the SHOULD level requirements for its REQUIRED level and all the SHOULD level requirements for its
protocols is said to be "unconditionally compliant"; one that protocols is said to be "unconditionally compliant"; one that
satisfies all the MUST level requirements but not all the SHOULD satisfies all the MUST level requirements but not all the SHOULD
level requirements for its protocols is said to be "conditionally level requirements for its protocols is said to be "conditionally
compliant." compliant."
2. Notational Conventions and Generic Grammar 2. Notational Conventions and Generic Grammar
This specification uses the ABNF syntax defined in Section 2.1 of This specification uses the ABNF syntax defined in Section 2.1 of
[Part1]. [[abnf.dep: ABNF syntax and basic rules will be adopted from [Part1].
RFC 5234, see <http://tools.ietf.org/wg/httpbis/trac/ticket/36>.]]
The ABNF rules below are defined in other specifications: The ABNF rules below are defined in other specifications:
OWS = <OWS, defined in [Part1], Section 2.2>
challenge = <challenge, defined in [RFC2617], Section 1.2> challenge = <challenge, defined in [RFC2617], Section 1.2>
credentials = <credentials, defined in [RFC2617], Section 1.2> credentials = <credentials, defined in [RFC2617], Section 1.2>
3. Status Code Definitions 3. Status Code Definitions
3.1. 401 Unauthorized 3.1. 401 Unauthorized
The request requires user authentication. The response MUST include The request requires user authentication. The response MUST include
a WWW-Authenticate header field (Section 4.4) containing a challenge a WWW-Authenticate header field (Section 4.4) containing a challenge
applicable to the requested resource. The client MAY repeat the applicable to the requested resource. The client MAY repeat the
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4. Header Field Definitions 4. Header Field Definitions
This section defines the syntax and semantics of HTTP/1.1 header This section defines the syntax and semantics of HTTP/1.1 header
fields related to authentication. fields related to authentication.
4.1. Authorization 4.1. Authorization
A user agent that wishes to authenticate itself with a server-- A user agent that wishes to authenticate itself with a server--
usually, but not necessarily, after receiving a 401 response--does so usually, but not necessarily, after receiving a 401 response--does so
by including an Authorization request-header field with the request. by including an Authorization request-header field with the request.
The Authorization field value consists of credentials containing the The field "Authorization" consists of credentials containing the
authentication information of the user agent for the realm of the authentication information of the user agent for the realm of the
resource being requested. resource being requested.
Authorization = "Authorization" ":" credentials Authorization = "Authorization" ":" OWS Authorization-v
Authorization-v = credentials
HTTP access authentication is described in "HTTP Authentication: HTTP access authentication is described in "HTTP Authentication:
Basic and Digest Access Authentication" [RFC2617]. If a request is Basic and Digest Access Authentication" [RFC2617]. If a request is
authenticated and a realm specified, the same credentials SHOULD be authenticated and a realm specified, the same credentials SHOULD be
valid for all other requests within this realm (assuming that the valid for all other requests within this realm (assuming that the
authentication scheme itself does not require otherwise, such as authentication scheme itself does not require otherwise, such as
credentials that vary according to a challenge value or using credentials that vary according to a challenge value or using
synchronized clocks). synchronized clocks).
When a shared cache (see Section 9 of [Part6]) receives a request When a shared cache (see Section 9 of [Part6]) receives a request
containing an Authorization field, it MUST NOT return the containing an Authorization field, it MUST NOT return the
corresponding response as a reply to any other request, unless one of corresponding response as a reply to any other request, unless one of
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subsequent request. But if the response is stale, all caches subsequent request. But if the response is stale, all caches
MUST first revalidate it with the origin server, using the MUST first revalidate it with the origin server, using the
request-headers from the new request to allow the origin server request-headers from the new request to allow the origin server
to authenticate the new request. to authenticate the new request.
3. If the response includes the "public" cache-control directive, it 3. If the response includes the "public" cache-control directive, it
MAY be returned in reply to any subsequent request. MAY be returned in reply to any subsequent request.
4.2. Proxy-Authenticate 4.2. Proxy-Authenticate
The Proxy-Authenticate response-header field MUST be included as part The response-header field "Proxy-Authenticate" MUST be included as
of a 407 (Proxy Authentication Required) response. The field value part of a 407 (Proxy Authentication Required) response. The field
consists of a challenge that indicates the authentication scheme and value consists of a challenge that indicates the authentication
parameters applicable to the proxy for this Request-URI. scheme and parameters applicable to the proxy for this Request-URI.
Proxy-Authenticate = "Proxy-Authenticate" ":" 1#challenge Proxy-Authenticate = "Proxy-Authenticate" ":" OWS
Proxy-Authenticate-v
Proxy-Authenticate-v = 1#challenge
The HTTP access authentication process is described in "HTTP The HTTP access authentication process is described in "HTTP
Authentication: Basic and Digest Access Authentication" [RFC2617]. Authentication: Basic and Digest Access Authentication" [RFC2617].
Unlike WWW-Authenticate, the Proxy-Authenticate header field applies Unlike WWW-Authenticate, the Proxy-Authenticate header field applies
only to the current connection and SHOULD NOT be passed on to only to the current connection and SHOULD NOT be passed on to
downstream clients. However, an intermediate proxy might need to downstream clients. However, an intermediate proxy might need to
obtain its own credentials by requesting them from the downstream obtain its own credentials by requesting them from the downstream
client, which in some circumstances will appear as if the proxy is client, which in some circumstances will appear as if the proxy is
forwarding the Proxy-Authenticate header field. forwarding the Proxy-Authenticate header field.
4.3. Proxy-Authorization 4.3. Proxy-Authorization
The Proxy-Authorization request-header field allows the client to The request-header field "Proxy-Authorization" allows the client to
identify itself (or its user) to a proxy which requires identify itself (or its user) to a proxy which requires
authentication. The Proxy-Authorization field value consists of authentication. The Proxy-Authorization field value consists of
credentials containing the authentication information of the user credentials containing the authentication information of the user
agent for the proxy and/or realm of the resource being requested. agent for the proxy and/or realm of the resource being requested.
Proxy-Authorization = "Proxy-Authorization" ":" credentials Proxy-Authorization = "Proxy-Authorization" ":" OWS
Proxy-Authorization-v
Proxy-Authorization-v = credentials
The HTTP access authentication process is described in "HTTP The HTTP access authentication process is described in "HTTP
Authentication: Basic and Digest Access Authentication" [RFC2617]. Authentication: Basic and Digest Access Authentication" [RFC2617].
Unlike Authorization, the Proxy-Authorization header field applies Unlike Authorization, the Proxy-Authorization header field applies
only to the next outbound proxy that demanded authentication using only to the next outbound proxy that demanded authentication using
the Proxy-Authenticate field. When multiple proxies are used in a the Proxy-Authenticate field. When multiple proxies are used in a
chain, the Proxy-Authorization header field is consumed by the first chain, the Proxy-Authorization header field is consumed by the first
outbound proxy that was expecting to receive credentials. A proxy outbound proxy that was expecting to receive credentials. A proxy
MAY relay the credentials from the client request to the next proxy MAY relay the credentials from the client request to the next proxy
if that is the mechanism by which the proxies cooperatively if that is the mechanism by which the proxies cooperatively
authenticate a given request. authenticate a given request.
4.4. WWW-Authenticate 4.4. WWW-Authenticate
The WWW-Authenticate response-header field MUST be included in 401 The WWW-Authenticate response-header field MUST be included in 401
(Unauthorized) response messages. The field value consists of at (Unauthorized) response messages. The field value consists of at
least one challenge that indicates the authentication scheme(s) and least one challenge that indicates the authentication scheme(s) and
parameters applicable to the Request-URI. parameters applicable to the Request-URI.
WWW-Authenticate = "WWW-Authenticate" ":" 1#challenge WWW-Authenticate = "WWW-Authenticate" ":" OWS WWW-Authenticate-v
WWW-Authenticate-v = 1#challenge
The HTTP access authentication process is described in "HTTP The HTTP access authentication process is described in "HTTP
Authentication: Basic and Digest Access Authentication" [RFC2617]. Authentication: Basic and Digest Access Authentication" [RFC2617].
User agents are advised to take special care in parsing the WWW- User agents are advised to take special care in parsing the WWW-
Authenticate field value as it might contain more than one challenge, Authenticate field value as it might contain more than one challenge,
or if more than one WWW-Authenticate header field is provided, the or if more than one WWW-Authenticate header field is provided, the
contents of a challenge itself can contain a comma-separated list of contents of a challenge itself can contain a comma-separated list of
authentication parameters. authentication parameters.
5. IANA Considerations 5. IANA Considerations
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[[anchor2: TBD.]] [[anchor2: TBD.]]
8. References 8. References
8.1. Normative References 8.1. Normative References
[Part1] Fielding, R., Ed., Gettys, J., Mogul, J., Frystyk, H., [Part1] Fielding, R., Ed., Gettys, J., Mogul, J., Frystyk, H.,
Masinter, L., Leach, P., Berners-Lee, T., Lafon, Y., Ed., Masinter, L., Leach, P., Berners-Lee, T., Lafon, Y., Ed.,
and J. Reschke, Ed., "HTTP/1.1, part 1: URIs, Connections, and J. Reschke, Ed., "HTTP/1.1, part 1: URIs, Connections,
and Message Parsing", draft-ietf-httpbis-p1-messaging-04 and Message Parsing", draft-ietf-httpbis-p1-messaging-05
(work in progress), August 2008. (work in progress), November 2008.
[Part6] Fielding, R., Ed., Gettys, J., Mogul, J., Frystyk, H., [Part6] Fielding, R., Ed., Gettys, J., Mogul, J., Frystyk, H.,
Masinter, L., Leach, P., Berners-Lee, T., Lafon, Y., Ed., Masinter, L., Leach, P., Berners-Lee, T., Lafon, Y., Ed.,
and J. Reschke, Ed., "HTTP/1.1, part 6: Caching", and J. Reschke, Ed., "HTTP/1.1, part 6: Caching",
draft-ietf-httpbis-p6-cache-04 (work in progress), draft-ietf-httpbis-p6-cache-05 (work in progress),
August 2008. November 2008.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2617] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S., [RFC2617] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,
Leach, P., Luotonen, A., and L. Stewart, "HTTP Leach, P., Luotonen, A., and L. Stewart, "HTTP
Authentication: Basic and Digest Access Authentication", Authentication: Basic and Digest Access Authentication",
RFC 2617, June 1999. RFC 2617, June 1999.
8.2. Informative References 8.2. Informative References
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Appendix B. Change Log (to be removed by RFC Editor before publication) Appendix B. Change Log (to be removed by RFC Editor before publication)
B.1. Since RFC2616 B.1. Since RFC2616
Extracted relevant partitions from [RFC2616]. Extracted relevant partitions from [RFC2616].
B.2. Since draft-ietf-httpbis-p7-auth-00 B.2. Since draft-ietf-httpbis-p7-auth-00
Closed issues: Closed issues:
o <http://www3.tools.ietf.org/wg/httpbis/trac/ticket/35>: "Normative o <http://tools.ietf.org/wg/httpbis/trac/ticket/35>: "Normative and
and Informative references" Informative references"
B.3. Since draft-ietf-httpbis-p7-auth-01 B.3. Since draft-ietf-httpbis-p7-auth-01
Ongoing work on ABNF conversion Ongoing work on ABNF conversion
(<http://www3.tools.ietf.org/wg/httpbis/trac/ticket/36>): (<http://tools.ietf.org/wg/httpbis/trac/ticket/36>):
o Explicitly import BNF rules for "challenge" and "credentials" from o Explicitly import BNF rules for "challenge" and "credentials" from
RFC2617. RFC2617.
o Add explicit references to BNF syntax and rules imported from o Add explicit references to BNF syntax and rules imported from
other parts of the specification. other parts of the specification.
B.4. Since draft-ietf-httpbis-p7-auth-02 B.4. Since draft-ietf-httpbis-p7-auth-02
Ongoing work on IANA Message Header Registration Ongoing work on IANA Message Header Registration
(<http://www3.tools.ietf.org/wg/httpbis/trac/ticket/40>): (<http://tools.ietf.org/wg/httpbis/trac/ticket/40>):
o Reference RFC 3984, and update header registrations for headers o Reference RFC 3984, and update header registrations for headers
defined in this document. defined in this document.
B.5. Since draft-ietf-httpbis-p7-auth-03 B.5. Since draft-ietf-httpbis-p7-auth-03
B.6. Since draft-ietf-httpbis-p7-auth-04
Ongoing work on ABNF conversion
(<http://tools.ietf.org/wg/httpbis/trac/ticket/36>):
o Use "/" instead of "|" for alternatives.
o Introduce new ABNF rules for "bad" whitespace ("BWS"), optional
whitespace ("OWS") and required whitespace ("RWS").
o Rewrite ABNFs to spell out whitespace rules, factor out header
value format definitions.
Index Index
4 4
401 Unauthorized (status code) 5 401 Unauthorized (status code) 5
407 Proxy Authentication Required (status code) 5 407 Proxy Authentication Required (status code) 5
A A
Authorization header 5 Authorization header 5
G G
Grammar Grammar
Authorization 5 Authorization 5
Authorization-v 5
challenge 4 challenge 4
credentials 4 credentials 4
Proxy-Authenticate 6 Proxy-Authenticate 6
Proxy-Authenticate-v 6
Proxy-Authorization 7 Proxy-Authorization 7
Proxy-Authorization-v 7
WWW-Authenticate 7 WWW-Authenticate 7
WWW-Authenticate-v 7
H H
Headers Headers
Authorization 5 Authorization 5
Proxy-Authenticate 6 Proxy-Authenticate 6
Proxy-Authorization 7 Proxy-Authorization 7
WWW-Authenticate 7 WWW-Authenticate 7
P P
Proxy-Authenticate header 6 Proxy-Authenticate header 6
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