HTTPbis Working Group R. Fielding, Ed.
Internet-Draft Adobe
Obsoletes: 2616 (if approved) J. Reschke, Ed.
Updates: 2617 (if approved) greenbytes
Intended status: Standards Track October 4, 2012
Expires: April 7, 2013
Hypertext Transfer Protocol (HTTP/1.1): Authentication
draft-ietf-httpbis-p7-auth-21
Abstract
The Hypertext Transfer Protocol (HTTP) is an application-level
protocol for distributed, collaborative, hypermedia information
systems. This document defines the HTTP Authentication framework.
Editorial Note (To be removed by RFC Editor)
Discussion of this draft takes place on the HTTPBIS working group
mailing list (ietf-http-wg@w3.org), which is archived at
.
The current issues list is at
and related
documents (including fancy diffs) can be found at
.
The changes in this draft are summarized in Appendix D.2.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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This Internet-Draft will expire on April 7, 2013.
Copyright Notice
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.1. Conformance and Error Handling . . . . . . . . . . . . . . 4
1.2. Syntax Notation . . . . . . . . . . . . . . . . . . . . . 4
2. Access Authentication Framework . . . . . . . . . . . . . . . 4
2.1. Challenge and Response . . . . . . . . . . . . . . . . . . 4
2.2. Protection Space (Realm) . . . . . . . . . . . . . . . . . 6
2.3. Authentication Scheme Registry . . . . . . . . . . . . . . 7
2.3.1. Considerations for New Authentication Schemes . . . . 7
3. Status Code Definitions . . . . . . . . . . . . . . . . . . . 9
3.1. 401 Unauthorized . . . . . . . . . . . . . . . . . . . . . 9
3.2. 407 Proxy Authentication Required . . . . . . . . . . . . 9
4. Header Field Definitions . . . . . . . . . . . . . . . . . . . 9
4.1. Authorization . . . . . . . . . . . . . . . . . . . . . . 9
4.2. Proxy-Authenticate . . . . . . . . . . . . . . . . . . . . 10
4.3. Proxy-Authorization . . . . . . . . . . . . . . . . . . . 10
4.4. WWW-Authenticate . . . . . . . . . . . . . . . . . . . . . 11
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12
5.1. Authentication Scheme Registry . . . . . . . . . . . . . . 12
5.2. Status Code Registration . . . . . . . . . . . . . . . . . 12
5.3. Header Field Registration . . . . . . . . . . . . . . . . 12
6. Security Considerations . . . . . . . . . . . . . . . . . . . 12
6.1. Authentication Credentials and Idle Clients . . . . . . . 13
6.2. Protection Spaces . . . . . . . . . . . . . . . . . . . . 13
7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 13
8. References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
8.1. Normative References . . . . . . . . . . . . . . . . . . . 14
8.2. Informative References . . . . . . . . . . . . . . . . . . 14
Appendix A. Changes from RFCs 2616 and 2617 . . . . . . . . . . . 15
Appendix B. Imported ABNF . . . . . . . . . . . . . . . . . . . . 15
Appendix C. Collected ABNF . . . . . . . . . . . . . . . . . . . 16
Appendix D. Change Log (to be removed by RFC Editor before
publication) . . . . . . . . . . . . . . . . . . . . 16
D.1. Since draft-ietf-httpbis-p7-auth-19 . . . . . . . . . . . 16
D.2. Since draft-ietf-httpbis-p7-auth-20 . . . . . . . . . . . 17
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
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1. Introduction
This document defines HTTP/1.1 access control and authentication. It
includes the relevant parts of RFC 2616 with only minor changes
([RFC2616]), plus the general framework for HTTP authentication, as
previously defined in "HTTP Authentication: Basic and Digest Access
Authentication" ([RFC2617]).
HTTP provides several OPTIONAL challenge-response authentication
mechanisms which can be used by a server to challenge a client
request and by a client to provide authentication information. The
"basic" and "digest" authentication schemes continue to be specified
in RFC 2617.
1.1. Conformance and Error Handling
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
Conformance criteria and considerations regarding error handling are
defined in Section 2.5 of [Part1].
1.2. Syntax Notation
This specification uses the Augmented Backus-Naur Form (ABNF)
notation of [RFC5234] with the list rule extension defined in Section
1.2 of [Part1]. Appendix B describes rules imported from other
documents. Appendix C shows the collected ABNF with the list rule
expanded.
2. Access Authentication Framework
2.1. Challenge and Response
HTTP provides a simple challenge-response authentication mechanism
that can be used by a server to challenge a client request and by a
client to provide authentication information. It uses an extensible,
case-insensitive token to identify the authentication scheme,
followed by additional information necessary for achieving
authentication via that scheme. The latter can either be a comma-
separated list of parameters or a single sequence of characters
capable of holding base64-encoded information.
Parameters are name-value pairs where the name is matched case-
insensitively, and each parameter name MUST only occur once per
challenge.
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auth-scheme = token
auth-param = token BWS "=" BWS ( token / quoted-string )
token68 = 1*( ALPHA / DIGIT /
"-" / "." / "_" / "~" / "+" / "/" ) *"="
The "token68" syntax allows the 66 unreserved URI characters
([RFC3986]), plus a few others, so that it can hold a base64,
base64url (URL and filename safe alphabet), base32, or base16 (hex)
encoding, with or without padding, but excluding whitespace
([RFC4648]).
The 401 (Unauthorized) response message is used by an origin server
to challenge the authorization of a user agent. This response MUST
include a WWW-Authenticate header field containing at least one
challenge applicable to the requested resource.
The 407 (Proxy Authentication Required) response message is used by a
proxy to challenge the authorization of a client and MUST include a
Proxy-Authenticate header field containing at least one challenge
applicable to the proxy for the requested resource.
challenge = auth-scheme [ 1*SP ( token68 / #auth-param ) ]
Note: User agents will need to take special care in parsing the
WWW-Authenticate and Proxy-Authenticate header field values
because they can contain more than one challenge, or if more than
one of each is provided, since the contents of a challenge can
itself contain a comma-separated list of authentication
parameters.
Note: Many clients fail to parse challenges containing unknown
schemes. A workaround for this problem is to list well-supported
schemes (such as "basic") first.
A user agent that wishes to authenticate itself with an origin server
-- usually, but not necessarily, after receiving a 401 (Unauthorized)
-- can do so by including an Authorization header field with the
request.
A client that wishes to authenticate itself with a proxy -- usually,
but not necessarily, after receiving a 407 (Proxy Authentication
Required) -- can do so by including a Proxy-Authorization header
field with the request.
Both the Authorization field value and the Proxy-Authorization field
value contain the client's credentials for the realm of the resource
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being requested, based upon a challenge received from the server
(possibly at some point in the past). When creating their values,
the user agent ought to do so by selecting the challenge with what it
considers to be the most secure auth-scheme that it understands,
obtaining credentials from the user as appropriate.
credentials = auth-scheme [ 1*SP ( token68 / #auth-param ) ]
Upon a request for a protected resource that omits credentials,
contains invalid credentials (e.g., a bad password) or partial
credentials (e.g., when the authentication scheme requires more than
one round trip), an origin server SHOULD return a 401 (Unauthorized)
response. Such responses MUST include a WWW-Authenticate header
field containing at least one (possibly new) challenge applicable to
the requested resource.
Likewise, upon a request that requires authentication by proxies that
omit credentials or contain invalid or partial credentials, a proxy
SHOULD return a 407 (Proxy Authentication Required) response. Such
responses MUST include a Proxy-Authenticate header field containing a
(possibly new) challenge applicable to the proxy.
A server receiving credentials that are valid, but not adequate to
gain access, ought to respond with the 403 (Forbidden) status code
(Section 7.5.3 of [Part2]).
The HTTP protocol does not restrict applications to this simple
challenge-response mechanism for access authentication. Additional
mechanisms MAY be used, such as encryption at the transport level or
via message encapsulation, and with additional header fields
specifying authentication information. However, such additional
mechanisms are not defined by this specification.
Proxies MUST forward the WWW-Authenticate and Authorization header
fields unmodified and follow the rules found in Section 4.1.
2.2. Protection Space (Realm)
The authentication parameter realm is reserved for use by
authentication schemes that wish to indicate the scope of protection.
A protection space is defined by the canonical root URI (the scheme
and authority components of the effective request URI; see Section
5.5 of [Part1]) of the server being accessed, in combination with the
realm value if present. These realms allow the protected resources
on a server to be partitioned into a set of protection spaces, each
with its own authentication scheme and/or authorization database.
The realm value is a string, generally assigned by the origin server,
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which can have additional semantics specific to the authentication
scheme. Note that there can be multiple challenges with the same
auth-scheme but different realms.
The protection space determines the domain over which credentials can
be automatically applied. If a prior request has been authorized,
the same credentials MAY be reused for all other requests within that
protection space for a period of time determined by the
authentication scheme, parameters, and/or user preference. Unless
otherwise defined by the authentication scheme, a single protection
space cannot extend outside the scope of its server.
For historical reasons, senders MUST only use the quoted-string
syntax. Recipients might have to support both token and quoted-
string syntax for maximum interoperability with existing clients that
have been accepting both notations for a long time.
2.3. Authentication Scheme Registry
The HTTP Authentication Scheme Registry defines the name space for
the authentication schemes in challenges and credentials.
Registrations MUST include the following fields:
o Authentication Scheme Name
o Pointer to specification text
o Notes (optional)
Values to be added to this name space require IETF Review (see
[RFC5226], Section 4.1).
The registry itself is maintained at
.
2.3.1. Considerations for New Authentication Schemes
There are certain aspects of the HTTP Authentication Framework that
put constraints on how new authentication schemes can work:
o HTTP authentication is presumed to be stateless: all of the
information necessary to authenticate a request MUST be provided
in the request, rather than be dependent on the server remembering
prior requests. Authentication based on, or bound to, the
underlying connection is outside the scope of this specification
and inherently flawed unless steps are taken to ensure that the
connection cannot be used by any party other than the
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authenticated user (see Section 2.3 of [Part1]).
o The authentication parameter "realm" is reserved for defining
Protection Spaces as defined in Section 2.2. New schemes MUST NOT
use it in a way incompatible with that definition.
o The "token68" notation was introduced for compatibility with
existing authentication schemes and can only be used once per
challenge/credentials. New schemes thus ought to use the "auth-
param" syntax instead, because otherwise future extensions will be
impossible.
o The parsing of challenges and credentials is defined by this
specification, and cannot be modified by new authentication
schemes. When the auth-param syntax is used, all parameters ought
to support both token and quoted-string syntax, and syntactical
constraints ought to be defined on the field value after parsing
(i.e., quoted-string processing). This is necessary so that
recipients can use a generic parser that applies to all
authentication schemes.
Note: The fact that the value syntax for the "realm" parameter is
restricted to quoted-string was a bad design choice not to be
repeated for new parameters.
o Definitions of new schemes ought to define the treatment of
unknown extension parameters. In general, a "must-ignore" rule is
preferable over "must-understand", because otherwise it will be
hard to introduce new parameters in the presence of legacy
recipients. Furthermore, it's good to describe the policy for
defining new parameters (such as "update the specification", or
"use this registry").
o Authentication schemes need to document whether they are usable in
origin-server authentication (i.e., using WWW-Authenticate),
and/or proxy authentication (i.e., using Proxy-Authenticate).
o The credentials carried in an Authorization header field are
specific to the User Agent, and therefore have the same effect on
HTTP caches as the "private" Cache-Control response directive,
within the scope of the request they appear in.
Therefore, new authentication schemes which choose not to carry
credentials in the Authorization header field (e.g., using a newly
defined header field) will need to explicitly disallow caching, by
mandating the use of either Cache-Control request directives
(e.g., "no-store") or response directives (e.g., "private").
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3. Status Code Definitions
3.1. 401 Unauthorized
The request requires user authentication. The response MUST include
a WWW-Authenticate header field (Section 4.4) containing a challenge
applicable to the target resource. The client MAY repeat the request
with a suitable Authorization header field (Section 4.1). If the
request already included Authorization credentials, then the 401
response indicates that authorization has been refused for those
credentials. If the 401 response contains the same challenge as the
prior response, and the user agent has already attempted
authentication at least once, then the user SHOULD be presented the
representation that was given in the response, since that
representation might include relevant diagnostic information.
3.2. 407 Proxy Authentication Required
This code is similar to 401 (Unauthorized), but indicates that the
client ought to first authenticate itself with the proxy. The proxy
MUST return a Proxy-Authenticate header field (Section 4.2)
containing a challenge applicable to the proxy for the target
resource. The client MAY repeat the request with a suitable Proxy-
Authorization header field (Section 4.3).
4. Header Field Definitions
This section defines the syntax and semantics of HTTP/1.1 header
fields related to authentication.
4.1. Authorization
The "Authorization" header field allows a user agent to authenticate
itself with a server -- usually, but not necessarily, after receiving
a 401 (Unauthorized) response. Its value consists of credentials
containing information of the user agent for the realm of the
resource being requested.
Authorization = credentials
If a request is authenticated and a realm specified, the same
credentials SHOULD be valid for all other requests within this realm
(assuming that the authentication scheme itself does not require
otherwise, such as credentials that vary according to a challenge
value or using synchronized clocks).
When a shared cache (see Section 1.2 of [Part6]) receives a request
containing an Authorization field, it MUST NOT return the
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corresponding response as a reply to any other request, unless one of
the following specific exceptions holds:
1. If the response includes the "s-maxage" cache-control directive,
the cache MAY use that response in replying to a subsequent
request. But (if the specified maximum age has passed) a proxy
cache MUST first revalidate it with the origin server, using the
header fields from the new request to allow the origin server to
authenticate the new request. (This is the defined behavior for
s-maxage.) If the response includes "s-maxage=0", the proxy MUST
always revalidate it before re-using it.
2. If the response includes the "must-revalidate" cache-control
directive, the cache MAY use that response in replying to a
subsequent request. But if the response is stale, all caches
MUST first revalidate it with the origin server, using the header
fields from the new request to allow the origin server to
authenticate the new request.
3. If the response includes the "public" cache-control directive, it
MAY be returned in reply to any subsequent request.
4.2. Proxy-Authenticate
The "Proxy-Authenticate" header field consists of at least one
challenge that indicates the authentication scheme(s) and parameters
applicable to the proxy for this effective request URI (Section 5.5
of [Part1]). It MUST be included as part of a 407 (Proxy
Authentication Required) response.
Proxy-Authenticate = 1#challenge
Unlike WWW-Authenticate, the Proxy-Authenticate header field applies
only to the current connection, and intermediaries SHOULD NOT forward
it to downstream clients. However, an intermediate proxy might need
to obtain its own credentials by requesting them from the downstream
client, which in some circumstances will appear as if the proxy is
forwarding the Proxy-Authenticate header field.
Note that the parsing considerations for WWW-Authenticate apply to
this header field as well; see Section 4.4 for details.
4.3. Proxy-Authorization
The "Proxy-Authorization" header field allows the client to identify
itself (or its user) to a proxy which requires authentication. Its
value consists of credentials containing the authentication
information of the user agent for the proxy and/or realm of the
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resource being requested.
Proxy-Authorization = credentials
Unlike Authorization, the Proxy-Authorization header field applies
only to the next outbound proxy that demanded authentication using
the Proxy-Authenticate field. When multiple proxies are used in a
chain, the Proxy-Authorization header field is consumed by the first
outbound proxy that was expecting to receive credentials. A proxy
MAY relay the credentials from the client request to the next proxy
if that is the mechanism by which the proxies cooperatively
authenticate a given request.
4.4. WWW-Authenticate
The "WWW-Authenticate" header field consists of at least one
challenge that indicates the authentication scheme(s) and parameters
applicable to the effective request URI (Section 5.5 of [Part1]).
It MUST be included in 401 (Unauthorized) response messages and MAY
be included in other response messages to indicate that supplying
credentials (or different credentials) might affect the response.
WWW-Authenticate = 1#challenge
User agents are advised to take special care in parsing the WWW-
Authenticate field value as it might contain more than one challenge,
or if more than one WWW-Authenticate header field is provided, the
contents of a challenge itself can contain a comma-separated list of
authentication parameters.
For instance:
WWW-Authenticate: Newauth realm="apps", type=1,
title="Login to \"apps\"", Basic realm="simple"
This header field contains two challenges; one for the "Newauth"
scheme with a realm value of "apps", and two additional parameters
"type" and "title", and another one for the "Basic" scheme with a
realm value of "simple".
Note: The challenge grammar production uses the list syntax as
well. Therefore, a sequence of comma, whitespace, and comma can
be considered both as applying to the preceding challenge, or to
be an empty entry in the list of challenges. In practice, this
ambiguity does not affect the semantics of the header field value
and thus is harmless.
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5. IANA Considerations
5.1. Authentication Scheme Registry
The registration procedure for HTTP Authentication Schemes is defined
by Section 2.3 of this document.
The HTTP Method Authentication Scheme shall be created at
.
5.2. Status Code Registration
The HTTP Status Code Registry located at
shall be updated
with the registrations below:
+-------+-------------------------------+-------------+
| Value | Description | Reference |
+-------+-------------------------------+-------------+
| 401 | Unauthorized | Section 3.1 |
| 407 | Proxy Authentication Required | Section 3.2 |
+-------+-------------------------------+-------------+
5.3. Header Field Registration
The Message Header Field Registry located at shall be
updated with the permanent registrations below (see [RFC3864]):
+---------------------+----------+----------+-------------+
| Header Field Name | Protocol | Status | Reference |
+---------------------+----------+----------+-------------+
| Authorization | http | standard | Section 4.1 |
| Proxy-Authenticate | http | standard | Section 4.2 |
| Proxy-Authorization | http | standard | Section 4.3 |
| WWW-Authenticate | http | standard | Section 4.4 |
+---------------------+----------+----------+-------------+
The change controller is: "IETF (iesg@ietf.org) - Internet
Engineering Task Force".
6. Security Considerations
This section is meant to inform application developers, information
providers, and users of the security limitations in HTTP/1.1 as
described by this document. The discussion does not include
definitive solutions to the problems revealed, though it does make
some suggestions for reducing security risks.
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6.1. Authentication Credentials and Idle Clients
Existing HTTP clients and user agents typically retain authentication
information indefinitely. HTTP/1.1 does not provide a method for a
server to direct clients to discard these cached credentials. This
is a significant defect that requires further extensions to HTTP.
Circumstances under which credential caching can interfere with the
application's security model include but are not limited to:
o Clients which have been idle for an extended period following
which the server might wish to cause the client to reprompt the
user for credentials.
o Applications which include a session termination indication (such
as a "logout" or "commit" button on a page) after which the server
side of the application "knows" that there is no further reason
for the client to retain the credentials.
This is currently under separate study. There are a number of work-
arounds to parts of this problem, and we encourage the use of
password protection in screen savers, idle time-outs, and other
methods which mitigate the security problems inherent in this
problem. In particular, user agents which cache credentials are
encouraged to provide a readily accessible mechanism for discarding
cached credentials under user control.
6.2. Protection Spaces
Authentication schemes that solely rely on the "realm" mechanism for
establishing a protection space will expose credentials to all
resources on a server. Clients that have successfully made
authenticated requests with a resource can use the same
authentication credentials for other resources on the same server.
This makes it possible for a different resource to harvest
authentication credentials for other resources.
This is of particular concern when a server hosts resources for
multiple parties under the same canonical root URI (Section 2.2).
Possible mitigation strategies include restricting direct access to
authentication credentials (i.e., not making the content of the
Authorization request header field available), and separating
protection spaces by using a different host name for each party.
7. Acknowledgments
This specification takes over the definition of the HTTP
Authentication Framework, previously defined in RFC 2617. We thank
John Franks, Phillip M. Hallam-Baker, Jeffery L. Hostetler, Scott D.
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Lawrence, Paul J. Leach, Ari Luotonen, and Lawrence C. Stewart for
their work on that specification. See Section 6 of [RFC2617] for
further acknowledgements.
See Section 9 of [Part1] for the Acknowledgments related to this
document revision.
8. References
8.1. Normative References
[Part1] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Message Syntax and Routing",
draft-ietf-httpbis-p1-messaging-21 (work in progress),
October 2012.
[Part2] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Semantics and Content",
draft-ietf-httpbis-p2-semantics-21 (work in progress),
October 2012.
[Part6] Fielding, R., Ed., Nottingham, M., Ed., and J. Reschke,
Ed., "Hypertext Transfer Protocol (HTTP/1.1): Caching",
draft-ietf-httpbis-p6-cache-21 (work in progress),
October 2012.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC5234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", STD 68, RFC 5234, January 2008.
8.2. Informative References
[RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.
[RFC2617] Franks, J., Hallam-Baker, P., Hostetler, J., Lawrence, S.,
Leach, P., Luotonen, A., and L. Stewart, "HTTP
Authentication: Basic and Digest Access Authentication",
RFC 2617, June 1999.
[RFC3864] Klyne, G., Nottingham, M., and J. Mogul, "Registration
Procedures for Message Header Fields", BCP 90, RFC 3864,
September 2004.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
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Resource Identifier (URI): Generic Syntax", STD 66,
RFC 3986, January 2005.
[RFC4648] Josefsson, S., "The Base16, Base32, and Base64 Data
Encodings", RFC 4648, October 2006.
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an
IANA Considerations Section in RFCs", BCP 26, RFC 5226,
May 2008.
Appendix A. Changes from RFCs 2616 and 2617
The "realm" parameter isn't required anymore in general;
consequently, the ABNF allows challenges without any auth parameters.
(Section 2)
The "token68" alternative to auth-param lists has been added for
consistency with legacy authentication schemes such as "Basic".
(Section 2)
Introduce Authentication Scheme Registry. (Section 2.3)
Appendix B. Imported ABNF
The following core rules are included by reference, as defined in
Appendix B.1 of [RFC5234]: ALPHA (letters), CR (carriage return),
CRLF (CR LF), CTL (controls), DIGIT (decimal 0-9), DQUOTE (double
quote), HEXDIG (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
character).
The rules below are defined in [Part1]:
BWS =
OWS =
quoted-string =
token =
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Appendix C. Collected ABNF
Authorization = credentials
BWS =
OWS =
Proxy-Authenticate = *( "," OWS ) challenge *( OWS "," [ OWS
challenge ] )
Proxy-Authorization = credentials
WWW-Authenticate = *( "," OWS ) challenge *( OWS "," [ OWS challenge
] )
auth-param = token BWS "=" BWS ( token / quoted-string )
auth-scheme = token
challenge = auth-scheme [ 1*SP ( token68 / [ ( "," / auth-param ) *(
OWS "," [ OWS auth-param ] ) ] ) ]
credentials = auth-scheme [ 1*SP ( token68 / [ ( "," / auth-param )
*( OWS "," [ OWS auth-param ] ) ] ) ]
quoted-string =
token =
token68 = 1*( ALPHA / DIGIT / "-" / "." / "_" / "~" / "+" / "/" )
*"="
Appendix D. Change Log (to be removed by RFC Editor before publication)
Changes up to the first Working Group Last Call draft are summarized
in .
D.1. Since draft-ietf-httpbis-p7-auth-19
Closed issues:
o : "Realms and
scope"
o : "Strength"
o :
"Authentication exchanges"
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o : "ABNF
requirements for recipients"
o : "note
introduction of new IANA registries as normative changes"
D.2. Since draft-ietf-httpbis-p7-auth-20
Closed issues:
o : "rename
b64token for clarity"
Other changes:
o Conformance criteria and considerations regarding error handling
are now defined in Part 1.
Index
4
401 Unauthorized (status code) 9
407 Proxy Authentication Required (status code) 9
A
Authorization header field 9
C
Canonical Root URI 6
G
Grammar
auth-param 5
auth-scheme 5
Authorization 9
challenge 5
credentials 6
Proxy-Authenticate 10
Proxy-Authorization 11
token68 5
WWW-Authenticate 11
P
Protection Space 6
Proxy-Authenticate header field 10
Proxy-Authorization header field 10
R
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Realm 6
W
WWW-Authenticate header field 11
Authors' Addresses
Roy T. Fielding (editor)
Adobe Systems Incorporated
345 Park Ave
San Jose, CA 95110
USA
EMail: fielding@gbiv.com
URI: http://roy.gbiv.com/
Julian F. Reschke (editor)
greenbytes GmbH
Hafenweg 16
Muenster, NW 48155
Germany
EMail: julian.reschke@greenbytes.de
URI: http://greenbytes.de/tech/webdav/
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