draft-ietf-kitten-sasl-oauth-00.txt   draft-ietf-kitten-sasl-oauth-01.txt 
KITTEN W. Mills KITTEN W. Mills
Internet-Draft T. Showalter Internet-Draft Yahoo! Inc.
Intended status: Standards Track Yahoo! Inc. Intended status: Standards Track T. Showalter
Expires: May 17, 2012 H. Tschofenig Expires: December 1, 2012
H. Tschofenig
Nokia Siemens Networks Nokia Siemens Networks
November 14, 2011 May 30, 2012
A SASL and GSS-API Mechanism for OAuth A SASL and GSS-API Mechanism for OAuth
draft-ietf-kitten-sasl-oauth-00.txt draft-ietf-kitten-sasl-oauth-01
Abstract Abstract
OAuth enables a third-party application to obtain limited access to a OAuth enables a third-party application to obtain limited access to a
protected resource, either on behalf of a resource owner by protected resource, either on behalf of a resource owner by
orchestrating an approval interaction, or by allowing the third-party orchestrating an approval interaction, or by allowing the third-party
application to obtain access on its own behalf. application to obtain access on its own behalf.
This document defines how an application client uses OAuth over the This document defines how an application client uses OAuth over the
Simple Authentication and Security Layer (SASL) or the Generic Simple Authentication and Security Layer (SASL) or the Generic
Security Service Application Program Interface (GSS-API) to access a Security Service Application Program Interface (GSS-API) to access a
protected resource at a resource serve, and additionally defines protected resource at a resource serve. Thereby, it enables schemes
authorization and token issuing endpoint discovery. Thereby, it defined within the OAuth framework for non-HTTP-based application
enables schemes defined within the OAuth framework for non-HTTP-based protocols.
application protocols.
Clients typically store the user's long term credential. This does, Clients typically store the user's long term credential. This does,
however, lead to significant security vulnerabilities, for example, however, lead to significant security vulnerabilities, for example,
when such a credential leaks. A significant benefit of OAuth for when such a credential leaks. A significant benefit of OAuth for
usage in those clients is that the password is replaced by a token. usage in those clients is that the password is replaced by a token.
Tokens typically provided limited access rights and can be managed Tokens typically provided limited access rights and can be managed
and revoked separately from the user's long-term credential and revoked separately from the user's long-term credential
(password). (password).
Status of this Memo Status of this Memo
skipping to change at page 2, line 4 skipping to change at page 2, line 4
Internet-Drafts are working documents of the Internet Engineering Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet- working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/. Drafts is at http://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months Internet-Drafts are draft documents valid for a maximum of six months
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."
This Internet-Draft will expire on May 17, 2012. This Internet-Draft will expire on December 1, 2012.
Copyright Notice Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the Copyright (c) 2012 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of (http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 7 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 7
3. OAuth SASL Mechanism Specification . . . . . . . . . . . . . . 8 3. OAuth SASL Mechanism Specification . . . . . . . . . . . . . . 8
3.1. Channel Binding . . . . . . . . . . . . . . . . . . . . . 8 3.1. Initial Client Response . . . . . . . . . . . . . . . . . 8
3.2. Initial Client Response . . . . . . . . . . . . . . . . . 8 3.1.1. Reserved Key/Values in OAUTH . . . . . . . . . . . . . 8
3.2.1. Query String in OAUTH-PLUS . . . . . . . . . . . . . . 9 3.2. Server's Response . . . . . . . . . . . . . . . . . . . . 9
3.3. Server's Response . . . . . . . . . . . . . . . . . . . . 9 3.2.1. Mapping to SASL Identities . . . . . . . . . . . . . . 9
3.4. Mapping to SASL Identities . . . . . . . . . . . . . . . . 10 3.2.2. Server response to failed authentication. . . . . . . 10
3.5. Discovery Information . . . . . . . . . . . . . . . . . . 10 3.3. Use of Signature Type Authorization . . . . . . . . . . . 10
3.6. Use of Signature Type Authorization . . . . . . . . . . . 12 3.4. Channel Binding . . . . . . . . . . . . . . . . . . . . . 11
4. GSS-API OAuth Mechanism Specification . . . . . . . . . . . . 14 4. GSS-API OAuth Mechanism Specification . . . . . . . . . . . . 12
5. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 5. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
5.1. Successful Bearer Token Exchange . . . . . . . . . . . . . 15 5.1. Successful Bearer Token Exchange . . . . . . . . . . . . . 13
5.2. MAC Authentication with Channel Binding . . . . . . . . . 15 5.2. MAC Authentication with Channel Binding . . . . . . . . . 13
5.3. Failed Exchange . . . . . . . . . . . . . . . . . . . . . 16 5.3. Failed Exchange . . . . . . . . . . . . . . . . . . . . . 14
5.4. Failed Channel Binding . . . . . . . . . . . . . . . . . . 17 5.4. Failed Channel Binding . . . . . . . . . . . . . . . . . . 15
6. Security Considerations . . . . . . . . . . . . . . . . . . . 18 6. Security Considerations . . . . . . . . . . . . . . . . . . . 16
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 19 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
7.1. SASL Registration . . . . . . . . . . . . . . . . . . . . 19 7.1. SASL Registration . . . . . . . . . . . . . . . . . . . . 17
7.2. GSS-API Registration . . . . . . . . . . . . . . . . . . . 19 7.2. GSS-API Registration . . . . . . . . . . . . . . . . . . . 17
7.3. Link Type Registration . . . . . . . . . . . . . . . . . . 19 8. Appendix A -- Document History . . . . . . . . . . . . . . . . 18
7.3.1. OAuth 2 Authentication Endpoint . . . . . . . . . . . 19 9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 19
7.3.2. OAuth 2 Token Endpoint . . . . . . . . . . . . . . . . 20 9.1. Normative References . . . . . . . . . . . . . . . . . . . 19
7.3.3. OAuth 1.0a Request Initiation Endpoint . . . . . . . . 20 9.2. Informative References . . . . . . . . . . . . . . . . . . 20
7.3.4. OAuth 1.0a Authorization Endpoint . . . . . . . . . . 21 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 21
7.3.5. OAuth 1.0a Token Endpoint . . . . . . . . . . . . . . 21
8. Appendix A -- Document History . . . . . . . . . . . . . . . . 22
9. References . . . . . . . . . . . . . . . . . . . . . . . . . . 23
9.1. Normative References . . . . . . . . . . . . . . . . . . . 23
9.2. Informative References . . . . . . . . . . . . . . . . . . 24
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 25
1. Introduction 1. Introduction
OAuth [I-D.ietf-oauth-v2] enables a third-party application to obtain OAuth [I-D.ietf-oauth-v2] enables a third-party application to obtain
limited access to a protected resource, either on behalf of a limited access to a protected resource, either on behalf of a
resource owner by orchestrating an approval interaction, or by resource owner by orchestrating an approval interaction, or by
allowing the third-party application to obtain access on its own allowing the third-party application to obtain access on its own
behalf. The core OAuth specification [I-D.ietf-oauth-v2] does not behalf. The core OAuth specification [I-D.ietf-oauth-v2] does not
define the interaction between the client and the resource server define the interaction between the client and the resource server
with the access to a protected resource using an Access Token. This with the access to a protected resource using an Access Token. This
skipping to change at page 6, line 4 skipping to change at page 6, line 4
validates the authorization grant, and if valid issues an access validates the authorization grant, and if valid issues an access
token. token.
(E) The client requests the protected resource from the resource (E) The client requests the protected resource from the resource
server and authenticates by presenting the access token. server and authenticates by presenting the access token.
(F) The resource server validates the access token, and if valid, (F) The resource server validates the access token, and if valid,
serves the request. serves the request.
Steps (E) and (F) are not defined in [I-D.ietf-oauth-v2] and are the Steps (E) and (F) are not defined in [I-D.ietf-oauth-v2] and are the
main functionality specified within this document. Additionally, an main functionality specified within this document. Consequently, the
optional discovery exchange is defined. Consequently, the message message exchange shown in Figure 2 is the result of this
exchange shown in Figure 2 is the result of this specification. (1) specification. The client will genrally need to determine the
and (2) denote the optional discovery exchange steps that may happen authentication endpoints (and perhaps the service endpoints) before
before the OAuth 2.0 protocol exchange messages in steps (A)-(D) are the OAuth 2.0 protocol exchange messages in steps (A)-(D) are
executed. Steps (E) and (F) also defined in this specification. executed. The discovery of the resource owner and authorization
server endpoints is outside the scope of this specification. The
client must discover those endpoints using a discovery mechanisms
such as Webfinger using host-meta [I-D.jones-appsawg-webfinger]. In
band discovery is not tenable if clients support the OAuth 2.0
password grant. Once credentials are obtained the client proceeds to
steps (E) and (F) defined in this specification.
----+ ----+
+--------+ +---------------+ | +--------+ +---------------+ |
| |--(A)-- Authorization Request --->| Resource | | | |--(A)-- Authorization Request --->| Resource | |
| | | Owner | |Plain | | | Owner | |Plain
| |<-(B)------ Access Grant ---------| | |OAuth | |<-(B)------ Access Grant ---------| | |OAuth
| | +---------------+ |2.0 | | +---------------+ |2.0
| | | | | |
| | Client Credentials & +---------------+ | | | Client Credentials & +---------------+ |
| |--(C)------ Access Grant -------->| Authorization | | | |--(C)------ Access Grant -------->| Authorization | |
| Client | | Server | | | Client | | Server | |
| |<-(D)------ Access Token ---------| | | | |<-(D)------ Access Token ---------| | |
| | (w/ Optional Refresh Token) +---------------+ | | | (w/ Optional Refresh Token) +---------------+ |
| | ----+ | | ----+
| |
| | ----+ | | ----+
| | (Optional discovery) +---------------+ | | | +---------------+ |
| |--(1)------- User Name --------->| | | | | | | |OAuth
| Client | | | | | |--(E)------ Access Token -------->| Resource | |over
| |<-(2)------ Authentication -------| | | | | | Server | |SASL/
| | endpoint information | Resource | |OAuth | |<-(F)---- Protected Resource -----| | |GSS-
| | | Server | |over | | | | |API
| |--(E)------ Access Token -------->| | |SASL/
| | | | |GSS-
| |<-(F)---- Protected Resource -----| | |API
+--------+ +---------------+ | +--------+ +---------------+ |
----+ ----+
Figure 2: OAuth SASL Architecture Figure 2: OAuth SASL Architecture
Note: The discovery procedure in OAuth is still work in progress.
Hence, the discovery components described in this document should
be considered incomplete and a tentative proposal. In general,
there is a trade off between a generic, externally available
defined discovery mechanisms (such as Webfinger using host-meta
[I-D.hammer-hostmeta], or [I-D.jones-simple-web-discovery]) and
configuration information exchanged in-band between the SASL
communication endpoints.
It is worthwhile to note that this specification is also compatible It is worthwhile to note that this specification is also compatible
with OAuth 1.0a [RFC5849]. with OAuth 1.0a [RFC5849].
2. Terminology 2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
The reader is assumed to be familiar with the terms used in the OAuth The reader is assumed to be familiar with the terms used in the OAuth
skipping to change at page 8, line 10 skipping to change at page 8, line 10
server respectively. Line breaks have been inserted for readability. server respectively. Line breaks have been inserted for readability.
Note that the IMAP SASL specification requires base64 encoding Note that the IMAP SASL specification requires base64 encoding
message, not this memo. message, not this memo.
3. OAuth SASL Mechanism Specification 3. OAuth SASL Mechanism Specification
SASL is used as a generalized authentication method in a variety of SASL is used as a generalized authentication method in a variety of
application layer protocols. This document defines two SASL application layer protocols. This document defines two SASL
mechanisms for usage with OAuth: "OAUTH" and "OAUTH-PLUS". The mechanisms for usage with OAuth: "OAUTH" and "OAUTH-PLUS". The
"OAUTH" SASL mechanism provides bearer token alike semantic for SASL "OAUTH" SASL mechanism enables OAuth authorizattion schemes for SASL,
while "OAUTH-PLUS" provides a semantic similar to OAuth MAC "OAUTH-PLUS" adds channel binding [RFC5056] capability for additional
authentication by utilizing a channel binding mechanism [RFC5056]. security guarantees.
3.1. Channel Binding
If the specification for the underlying authorization scheme requires
a security layer, such as TLS [RFC5246], the server SHOULD only offer
a mechanism where channel binding can be enabled.
The channel binding data is computed by the client based on it's 3.1. Initial Client Response
choice of preferred channel binding type. As specified in [RFC5056],
the channel binding information MUST start with the channel binding
unique prefix, followed by a colon (ASCII 0x3A), followed by a base64
encoded channel binding payload. The channel binding payload is the
raw data from the channel binding type if the raw channel binding
data is less than 500 bytes. If the raw channel binding data is 500
bytes or larger then a SHA-1 [RFC3174] hash of the raw channel
binding data is computed.
If the client is using tls-unique for a channel binding then the raw Client responses are a key/value pair sequence. These key/value
channel binding data equals the first TLS finished message. This is pairs carry the equivalent values form an HTTP context in order to be
under the 500 byte limit, so the channel binding payload sent to the able to complete an OAuth style HTTP authorization. The ABNF
server would be the base64 encoded first TLS finished message. [RFC2234] syntax is:
In the case where the client has chosen tls-endpoint, the raw channel kvsep = %x01
binding data is the certificate of the server the client connected key = 1*ALPHA
to, which will frequently be 500 bytes or more. If it is then the value = *(VCHAR | SP | HTAB | CR | LF )
channel binding payload is the base64 encoded SHA-1 hash of the kvpair = key "=" value kvsep
server certificate. client_resp = 1*kvpair kvsep
3.2. Initial Client Response The following key/value pairs are defined in the client response:
The SASL client response is formatted as an HTTP [RFC2616] request. auth (REQUIRED): The payload of the HTTP Authorization header for
The HTTP request is limited in that the path MUST be "/". In the an equivalent HTTP OAuth authroization.
OAUTH mechanism no query string is allowed. The following header
lines are defined in the client response:
User (OPTIONAL): Contains the user identifier being host: Contains the host name to which the client connected.
authenticated, and is provided to allow correct discovery
information to be returned.
Host (REQUIRED): Contains the host name to which the client port: Contains the port number represented as a decimal positive
integer string without leading zeros to which the client
connected. connected.
Authorization (REQUIRED): An HTTP Authorization header. In authorization schemes that use signatures, the client MUST send
host and port number key/values, and the server MUST fail
authorization request requiring signatures that do not have host and
port values.
The user name is provided by the client to allow the discovery 3.1.1. Reserved Key/Values in OAUTH
information to be customized for the user, a given server could allow
multiple authenticators and it needs to return the correct one. For
instance, a large ISP could provide mail service for several domains
who manage their own user information. For instance, users at foo-
example.com could be authenticated by an OAuth service at
https://oauth.foo-example.com/, and users at bar-example.com could be
authenticated by https://oauth.bar-example.com, but both could be
served by a hypothetical IMAP server running at a third domain,
imap.example.net.
3.2.1. Query String in OAUTH-PLUS In the OAUTH mechanism values for path, query string and post body
are assigned default values. OAuth authorization schemes MAY define
usage of these in the SASL context and extend this specification.
For OAuth schemes that use request signatures the default values MUST
be used unless explict values are provided in the client response.
The following key values are reserved for future use:
In the OAUTH-PLUS mechanism the channel binding information is path (RESERVED): HTTP path data, the default value is "/".
carried in the query string. OAUTH-PLUS defines following query
parameter(s):
cbdata (REQUIRED): Contains the base64 encoded channel binding qs (RESERVED): HTTP query string, the default value is "".
data, properly escaped as an HTML query parameter value.
3.3. Server's Response post (RESERVED): HTTP post data, the default value is "".
3.2. Server's Response
The server validates the response per the specification for the The server validates the response per the specification for the
authorization scheme used. If the authorization scheme used includes authorization scheme used. If the authorization scheme used includes
signing of the request parameters the client must provide a complete signing of the request parameters the client must provide a client
HTTP style request that satisfies the data requirements for the response that satisfies the data requirements for the scheme in use.
scheme in use.
In the OAUTH-PLUS mechanism the server examines the channel binding In the OAUTH-PLUS mechanism the server examines the channel binding
data, extracts the channel binding unique prefix, and extracts the data, extracts the channel binding unique prefix, and extracts the
raw channel biding data based on the channel binding type used. It raw channel biding data based on the channel binding type used. It
then computes it's own copy of the channel binding payload and then computes it's own copy of the channel binding payload and
compares that to the payload sent by the client in the query compares that to the payload sent by the client in the cbdata key/
parameters of the tunneled HTTP request. Those two must be equal for value. Those two must be equal for channel binding to succeed.
channel binding to succeed.
The server responds to a successfully verified client message by The server responds to a successfully verified client message by
completing the SASL negotiation. The authentication scheme MUST completing the SASL negotiation. The authentication scheme MUST
carry the user ID to be used as the authorization identity (identity carry the user ID to be used as the authorization identity (identity
to act as). The server MUST use that ID as the user being to act as). The server MUST use the ID obtained from the credential
authorized, that is the user assertion we accept and not other as the user being authorized.
information such as from the URL or "User:" header.
The server responds to failed authentication by sending discovery
information in an HTTP style response with the HTTP status code set
to 401, and then failing the authentication.
If channel binding is in use and the channel binding fails the server
responds with a minimal HTTP response without discovery information
and the HTTP status code set to 412 to indicate that the channel
binding precondition failed. If the authentication scheme in use
does not include signing the server SHOULD revoke the presented
credential and the client SHOULD discard that credential.
3.4. Mapping to SASL Identities 3.2.1. Mapping to SASL Identities
Some OAuth mechanisms can provide both an authorization identity and Some OAuth mechanisms can provide both an authorization identity and
an authentication identity. An example of this is OAuth 1.0a an authentication identity. An example of this is OAuth 1.0a
[RFC5849] where the consumer key (oauth_consumer_key) identifies the [RFC5849] where the consumer key (oauth_consumer_key) identifies the
entity using to token which equates to the SASL authentication entity using to token which equates to the SASL authentication
identity, and is authenticated using the shared secret. The identity, and is authenticated using the shared secret. The
authorization identity in the OAuth 1.0a case is carried in the token authorization identity in the OAuth 1.0a case is carried in the token
(per the requirement above), which SHOULD validated independently. (per the requirement above), which SHOULD validated independently.
The server MAY use a consumer key or other comparable identity in the The server MAY use a consumer key, a value derived from it, or other
OAuth authorization scheme as the SASL authentication identity. If comparable identity in the OAuth authorization scheme as the SASL
an appropriate authentication identity is not available the server authentication identity. If an appropriate authentication identity
MUST use the identity asserted in the token. is not available the server MUST use the authorization identity as
the wuthentication identity.
3.5. Discovery Information
The server MUST send discovery information in response to a failed
authentication exchange or a request with an empty Authorization
header. If discovery information is returned it MUST include an
authentication endpoint appropriate for the user. If the "User"
header is present the discovery information MUST be for that user.
Discovery information is provided by the server to the client to
allow a client to discover the appropriate OAuth authentication and
token endpoints. The client then uses that information to obtain the
access token needed for OAuth authentication. The client SHOULD
cache and re-use the user specific discovery information for service
endpoints.
Discovery information makes use of both the WWW-Authenticate header
as defined in HTTP Authentication: Basic and Digest Access
Authentication [RFC2617] and Link headers as defined in [RFC5988].
The following elements are defined for discovery information:
WWW-Authenticate A WWW-Authenticate header for each authentication
scheme supported by the server. Authentication scheme names are
case insensitive. The following [RFC2617] authentication
parameters are defined:
realm REQUIRED -- (as defined by RFC2617)
scope OPTIONAL -- A quoted string. This provides the client an
OAuth 2 scope known to be valid for the resource.
oauth2-authenticator An [RFC5988] Link header specifying the
[I-D.ietf-oauth-v2] authentication endpoint. This link has an
OPTIONAL link-extension "scheme", if included this link applies
ONLY to the specified scheme.
oauth2-token An [RFC5988] Link header specifying the
[I-D.ietf-oauth-v2] token endpoint. This link has an OPTIONAL
link-extension "scheme", if included this link applies ONLY to the
specified scheme.
oauth-initiate (Optional) An [RFC5988] Link header specifying the 3.2.2. Server response to failed authentication.
OAuth1.0a [RFC5849] initiation endpoint. The server MUST send
this if "OAuth" is included in the supported list of HTTP
authentication schemes for the server.
oauth-authorize (Optional) An [RFC5988] Link header specifying the For a failed authentication the server returns a JSON [RFC4627]
OAuth1.0a [RFC5849] authentication endpoint. The server MUST send formatted error result, and fails the authentication. The error
this if "OAuth" is included in the supported list of HTTP result consists of the following values:
authentication schemes for the server.
oauth-token (Optional) An [RFC5988] Link header specifying the status (REQUIRED): The authorization error code. Valid error
OAuth1.0a [RFC5849] token endpoint. The server MUST send this if codes are defined in the IANA [[need registry name]] registry
"OAuth" is included in the supported list of HTTP authentication specified in the OAuth 2 core specification.
schemes for the server. This link type has one link-extension
"grant-types" which is a space separated list of the OAuth 2.0
grant types that can be used at the token endpoint to obtain a
token.
Usage of the URLs provided in the discovery information is defined in scope (OPTIONAL): The OAuth scope required to access the service.
the relevant specifications. If the server supports multiple
authenticators the discovery information returned for unknown users
MUST be consistent with the discovery information for known users to
prevent user enumeration. The OAuth 2.0 specification
[I-D.ietf-oauth-v2] supports multiple types of authentication schemes
and the server MUST specify at least one supported authentication
scheme in the discovery information. The server MAY support multiple
schemes and MAY support schemes not listed in the discovery
information.
If the resource server provides a scope the client SHOULD always If the resource server provides a scope the client SHOULD always
request scoped tokens from the token endpoint. The client MAY use a request scoped tokens from the token endpoint. The client MAY use a
scope other than the one provided by the resource server. Scopes scope other than the one provided by the resource server. Scopes
other than those advertised by the resource server must be defined by other than those advertised by the resource server are be defined by
the resource owner and provided in service documentation (which is the resource owner and provided in service documentation or discovery
beyond the scope of this memo). information (which is beyond the scope of this memo). If not present
then the client SHOULD presume an empty scope (unscoped token) is
needed.
3.6. Use of Signature Type Authorization If channel binding is in use and the channel binding fails the server
responds with a status code set to 412 to indicate that the channel
binding precondition failed. If the authentication scheme in use
does not include signing the server SHOULD revoke the presented
credential and the client SHOULD discard that credential.
3.3. Use of Signature Type Authorization
This mechanism supports authorization using signatures, which This mechanism supports authorization using signatures, which
requires that both client and server construct the string to be requires that both client and server construct the string to be
signed. OAuth 2 is designed for authentication/authorization to signed. OAuth 2 is designed for authentication/authorization to
access specific URIs. SASL is designed for user authentication, and access specific URIs. SASL is designed for user authentication, and
has no facility for being more specific. In this mechanism we has no facility for being more specific. In this mechanism we
require an HTTP style format specifically to support signature type require or define default values for the data elements from an HTTP
authentication, but this is extremely limited. The HTTP style request which allow the signature base string to be constructed
request is limited to a path of "/". This mechanism is in the SASL properly. The default HTTP path is "/" and the default post body is
model, but is designed so that no changes are needed if there is a empty. These atoms are defined as extension points so that no
revision of SASL which supports more specific resource authorization, changes are needed if there is a revision of SASL which supports more
e.g. IMAP access to a specific folder or FTP access limited to a specific resource authorization, e.g. IMAP access to a specific
specific directory. folder or FTP access limited to a specific directory.
Using the example in the MAC specification Using the example in the MAC specification
[I-D.ietf-oauth-v2-http-mac] as a starting point, on an IMAP server [I-D.ietf-oauth-v2-http-mac] as a starting point, on an IMAP server
running on port 143 and given the MAC style authorization request running on port 143 and given the MAC style authorization request
(with long lines wrapped for readability) below: (with %x01 shown as ^A and long lines wrapped for readability) below:
GET / HTTP/1.1 host=server.example.com^A
Host: server.example.com port=143^A
User: user@example.com auth=MAC token="h480djs93hd8",timestamp="137131200",nonce="dj83hs9s",
Authorization: MAC token="h480djs93hd8",timestamp="137131200", signature="YTVjyNSujYs1WsDurFnvFi4JK6o="^A^A
nonce="dj83hs9s",signature="YTVjyNSujYs1WsDurFnvFi4JK6o="
The normalized request string would be constructed per the MAC The normalized request string would be constructed per the MAC
specification [I-D.ietf-oauth-v2-http-mac]. In this example the specification [I-D.ietf-oauth-v2-http-mac]. In this example the
normalized request string with the new line separator character is normalized request string with the new line separator character is
represented by "\n" for display purposes only would be: represented by "\n" for display purposes only would be:
h480djs93hi8\n h480djs93hi8\n
137131200\n 137131200\n
dj83hs9s\n dj83hs9s\n
\n \n
GET\n GET\n
server.example.com\n server.example.com\n
143\n 143\n
/\n /\n
\n \n
3.4. Channel Binding
If the specification for the underlying authorization scheme requires
a security layer, such as TLS [RFC5246], the server SHOULD only offer
a mechanism where channel binding can be enabled.
The channel binding data is computed by the client based on it's
choice of preferred channel binding type. As specified in [RFC5056],
the channel binding information MUST start with the channel binding
unique prefix, followed by a colon (ASCII 0x3A), followed by a base64
encoded channel binding payload. The channel binding payload is the
raw data from the channel binding type if the raw channel binding
data is less than 500 bytes. If the raw channel binding data is 500
bytes or larger then a SHA-1 [RFC3174] hash of the raw channel
binding data is computed.
If the client is using tls-unique for a channel binding then the raw
channel binding data equals the first TLS finished message. This is
under the 500 byte limit, so the channel binding payload sent to the
server would be the base64 encoded first TLS finished message.
In the case where the client has chosen tls-endpoint, the raw channel
binding data is the certificate of the server the client connected
to, which will frequently be 500 bytes or more. If it is then the
channel binding payload is the base64 encoded SHA-1 hash of the
server certificate.
4. GSS-API OAuth Mechanism Specification 4. GSS-API OAuth Mechanism Specification
Note: The normative references in this section are informational for Note: The normative references in this section are informational for
SASL implementers, but they are normative for GSS-API implementers. SASL implementers, but they are normative for GSS-API implementers.
The SASL OAuth mechanism is also a GSS-API mechanism and the messages The SASL OAuth mechanism is also a GSS-API mechanism and the messages
described in Section 3 are the same, but described in Section 3 are the same, but
1. the GS2 header on the client's first message is excluded when 1. the GS2 header on the client's first message is excluded when
OAUTH is used as a GSS-API mechanism, and OAUTH is used as a GSS-API mechanism, and
skipping to change at page 15, line 20 skipping to change at page 13, line 20
5.1. Successful Bearer Token Exchange 5.1. Successful Bearer Token Exchange
This example shows a successful OAuth 2.0 bearer token exchange with This example shows a successful OAuth 2.0 bearer token exchange with
an initial client response. Note that line breaks are inserted for an initial client response. Note that line breaks are inserted for
readability. readability.
S: * IMAP4rev1 Server Ready S: * IMAP4rev1 Server Ready
C: t0 CAPABILITY C: t0 CAPABILITY
S: * CAPABILITY IMAP4rev1 AUTH=OAUTH S: * CAPABILITY IMAP4rev1 AUTH=OAUTH
S: t0 OK Completed S: t0 OK Completed
C: t1 AUTHENTICATE OAUTH R0VUIC8gSFRUUC8xLjENCkhvc3Q6IGltYXAuZXhhbXBs C: t1 AUTHENTICATE OAUTH aG9zdD1zZXJ2ZXIuZXhhbXBsZS5jb20BcG9ydD0xNDMB
ZS5jb20NCkF1dGhvcml6YXRpb246IEJFQVJFUiAidkY5ZGZ0NHFtVGMyTnZiM1J YXV0aD1CRUFSRVIgdkY5ZGZ0NHFtVGMyTnZiM1JsY2tCaGJIUmhkbWx6ZEdFdVk
sY2tCaGJIUmhkbWx6ZEdFdVkyOXRDZz09Ig0KDQo= yOXRDZz09AQE=
S: + S: +
S: t1 OK SASL authentication succeeded S: t1 OK SASL authentication succeeded
As required by IMAP [RFC3501], the payloads are base64-encoded. The As required by IMAP [RFC3501], the payloads are base64-encoded. The
decoded initial client response is: decoded initial client response (with %x01 represented as ^A and long
lines wrapped for readability) is:
GET / HTTP/1.1 host=server.example.com^Aport=143^A
Host: imap.example.com auth=BEARER "vF9dft4qmTc2Nvb3RlckBhbHRhdmlzdGEuY29tCg=="^A^A
Authorization: BEARER "vF9dft4qmTc2Nvb3RlckBhbHRhdmlzdGEuY29tCg=="
The line containing just a "+" and a space is an empty response from The line containing just a "+" and a space is an empty response from
the server. This response contains discovery information, and in the the server. This response contains error information, and in the
success case no discovery information is necessary so the response is success case the error response is empty. Like other messages, and
empty. Like other messages, and in accordance with the IMAP SASL in accordance with the IMAP SASL binding, the empty response is
binding, the empty response is base64-encoded. base64-encoded.
5.2. MAC Authentication with Channel Binding 5.2. MAC Authentication with Channel Binding
This example shows a channel binding failure. The example sends the This example shows a channel binding failure. The example sends the
same request as above, but in the context of an OAUTH-PLUS exchange same request as above, but in the context of an OAUTH-PLUS exchange
the channel binding information is missing. Note that line breaks the channel binding information is missing. Note that line breaks
are inserted for readability. are inserted for readability.
S: * CAPABILITY IMAP4rev1 AUTH=OAUTH SASL-IR IMAP4rev1 Server Ready S: * CAPABILITY IMAP4rev1 AUTH=OAUTH SASL-IR IMAP4rev1 Server Ready
S: t0 OK Completed S: t0 OK Completed
C: t1 AUTHENTICATE MAC R0VUIC8/Y2JkYXRhPSJTRzkzSUdKcFp5QnBjeUJoSUZSTVV5Q C: t1 AUTHENTICATE MAC aG9zdD1zZXJ2ZXIuZXhhbXBsZS5jb20BcG9ydD0xNDMBYXV0a
m1hVzVoYkNCdFpYTnpZV2RsUHdvPSIgSFRUUC8xLjENCkhvc3Q6IHNlcnZlci5leGFtcG D1NQUMgdG9rZW49Img0ODBkanM5M2hkOCIsdGltZXN0YW1wPSIxMzcxMzEyMDAiLG5vbm
xlLmNvbQ0KVXNlcjogdXNlckBleGFtcGxlLmNvbQ0KQXV0aG9yaXphdGlvbjogTUFDIHR NlPSJkajgzaHM5cyIsc2lnbmF0dXJlPSJZVFZqeU5TdWpZczFXc0R1ckZudkZpNEpLNm8
va2VuPSJoNDgwZGpzOTNoZDgiLHRpbWVzdGFtcD0iMTM3MTMxMjAwIixub25jZT0iZGo4 9IgFjYmRhdGE9U0c5M0lHSnBaeUJwY3lCaElGUk1VeUJtYVc1aGJDQnRaWE56WVdkbFB3
M2hzOXMiLHNpZ25hdHVyZT0iV1c5MUlHMTFjM1FnWW1VZ1ltOXlaV1F1SUFvPSINCg0K bz0BAQ==
S: + S: +
S: t1 OK SASL authentication succeeded S: t1 OK SASL authentication succeeded
As required by IMAP [RFC3501], the payloads are base64-encoded. The As required by IMAP [RFC3501], the payloads are base64-encoded. The
decoded initial client response is: decoded initial client response (with %x01 represented as ^A and long
lines wrapped for readability) is:
GET /?cbdata="SG93IGJpZyBpcyBhIFRMUyBmaW5hbCBtZXNzYWdlPwo=" HTTP/1.1 -
Host: server.example.com host=server.example.com^A
User: user@example.com port=143^A
Authorization: MAC token="h480djs93hd8",timestamp="137131200", auth=MAC token="h480djs93hd8",timestamp="137131200",nonce="dj83hs9s",
nonce="dj83hs9s",signature="WW91IG11c3QgYmUgYm9yZWQuIAo=" signature="YTVjyNSujYs1WsDurFnvFi4JK6o="^A
cbdata=SG93IGJpZyBpcyBhIFRMUyBmaW5hbCBtZXNzYWdlPwo=^A^A
The line containing just a "+" and a space is an empty response from The line containing just a "+" and a space is an empty response from
the server. This response contains discovery information, and in the the server. This response contains discovery information, and in the
success case no discovery information is necessary so the response is success case no discovery information is necessary so the response is
empty. Like other messages, and in accordance with the IMAP SASL empty. Like other messages, and in accordance with the IMAP SASL
binding, the empty response is base64-encoded. binding, the empty response is base64-encoded.
5.3. Failed Exchange 5.3. Failed Exchange
This example shows a failed exchange because of the empty This example shows a failed exchange because of the empty
Authorization header, which is how a client can query for discovery Authorization header, which is how a client can query for the needed
information. Note that line breaks are inserted for readability. scope. Note that line breaks are inserted for readability.
S: * CAPABILITY IMAP4rev1 AUTH=OAUTH SASL-IR IMAP4rev1 Server Ready S: * CAPABILITY IMAP4rev1 AUTH=OAUTH SASL-IR IMAP4rev1 Server Ready
S: t0 OK Completed S: t0 OK Completed
C: t1 AUTHENTICATE OAUTH R0VUIC8gSFRUUC8xLjENClVzZXI6IHNjb290ZXJAYW C: t1 AUTHENTICATE OAUTH aG9zdD1zZXJ2ZXIuZXhhbXBsZS5jb20BcG9ydD0xND
x0YXZpc3RhLmNvbQ0KSG9zdDogaW1hcC55YWhvby5jb20NCkF1dGhlbnRpY2F0ZT MBYXV0aD0BAQ==
ogDQoNCg== S: + ewoic3RhdHVzIjoiNDAxIiwKInNjb3BlIjoiZXhhbXBsZV9zY29wZSIKfQo=
S: + SFRUUC8xLjEgNDAxIFVuYXV0aG9yaXplZA0KV1dXLUF1dGhlbnRpY2F0ZTogQk
VBUkVSIHJlYWxtPSJleGFtcGxlLmNvbSINCkxpbms6IDxodHRwczovL2xvZ2luLn
lhaG9vLmNvbS9vYXV0aD4gcmVsPSJvYXV0aDItYXV0aGVudGljYXRvciIgIA0KTG
luazogPGh0dHBzOi8vbG9naW4ueWFob28uY29tL29hdXRoPiByZWw9Im91YXRoMi
10b2tlbiINCg0K
S: t1 NO SASL authentication failed S: t1 NO SASL authentication failed
The decoded initial client response is: The decoded initial client response is:
GET / HTTP/1.1 host=server.example.com^Aport=143^Aauth=^A^A
User: alice@example.com
Host: imap.example.com
Authorization:
The decoded server discovery response is: The decoded server error response is:
HTTP/1.1 401 Unauthorized {
WWW-Authenticate: BEARER realm="example.com" "status":"401",
Link: <https://login.example.com/oauth> rel="oauth2-authenticator" "scope":"example_scope"
Link: <https://login.example.com/oauth> rel="oauth2-token" }
5.4. Failed Channel Binding 5.4. Failed Channel Binding
This example shows a channel binding failure in a discovery request. This example shows a channel binding failure in an empty request.
The channel binding information is empty. Note that line breaks are The channel binding information is empty. Note that line breaks are
inserted for readability. inserted for readability.
S: * CAPABILITY IMAP4rev1 AUTH=OAUTH SASL-IR IMAP4rev1 Server Ready S: * CAPABILITY IMAP4rev1 AUTH=OAUTH SASL-IR IMAP4rev1 Server Ready
S: t0 OK Completed S: t0 OK Completed
C: t1 AUTHENTICATE OAUTH R0VUIC8/Y2JkYXRhPSIiIEhUVFAvMS4xDQpVc2VyOi C: t1 AUTHENTICATE OAUTH aG9zdD1zZXJ2ZXIuZXhhbXBsZS5jb20BcG9ydD0xND
BhbGljZUBleGFtcGxlLmNvbQ0KSG9zdDogaW1hcC5leGFtcGxlLmNvbQ0KQXV0aG MBYXV0aD0BY2JkYXRhPQEB
9yaXphdGlvbjoNCg0K S: + ewoic3RhdHVzIjoiNDEyIiwKInNjb3BlIjoiZXhhbXBsZV9zY29wZSIKfQ==
S: + SFRUUC8xLjEgNDEyIFByZWNvbmRpdGlvbiBGYWlsZWQNCg0KDQo=
S: t1 NO SASL authentication failed S: t1 NO SASL authentication failed
The decoded initial client response is: The decoded initial client response is:
GET /?cbdata="" HTTP/1.1 host=server.example.com^Aport=143^Aauth=^Acbdata=^A^A
User: alice@example.com
Host: imap.example.com
Authorization:
The decoded server response is: The decoded server response is:
HTTP/1.1 412 Precondition Failed {
"status":"412",
"scope":"example_scope"
}
6. Security Considerations 6. Security Considerations
This mechanism does not provide a security layer, but does provide a This mechanism does not provide a security layer, but does provide a
provision for channel binding. The OAuth 2 specification provision for channel binding. The OAuth 2 specification
[I-D.ietf-oauth-v2] allows for a variety of usages, and the security [I-D.ietf-oauth-v2] allows for a variety of usages, and the security
properties of these profiles vary. The usage of bearer tokens, for properties of these profiles vary. The usage of bearer tokens, for
example, provide security features similar to cookies. Applications example, provide security features similar to cookies. Applications
using this mechanism SHOULD exercise the same level of care using using this mechanism SHOULD exercise the same level of care using
this mechanism as they would in using the SASL PLAIN mechanism. In this mechanism as they would in using the SASL PLAIN mechanism. In
particular, TLS 1.2 or an equivalent secure channel MUST be particular, TLS 1.2 or an equivalent secure channel MUST be
implemented and its usage is RECOMMENDED. implemented and its usage is RECOMMENDED.
Channel binding in this mechanism has different properties based on Channel binding in this mechanism has different properties based on
the authentication scheme used. Channel binding to TLS with a bearer the authentication scheme used. Channel binding to TLS with a bearer
token provides only a binding to the TLS layer. Authentication token provides only a binding to the TLS layer. Authentication
schemes like MAC tokens have a signature over the channel binding schemes like MAC tokens can implement a signature over the channel
information. These provide additional protection against a man in binding information. These provide additional protection against a
the middle attacks, and the MAC authorization header is bound to the man in the middle attacks, and the MAC authorization header is bound
channel and only valid in that context. to the channel and only valid in that context.
It is possible that SASL will be authenticating a connection and the It is possible that SASL will be authenticating a connection and the
life of that connection may outlast the life of the token used to life of that connection may outlast the life of the token used to
authenticate it. This is a common problem in application protocols authenticate it. This is a common problem in application protocols
where connections are long-lived, and not a problem with this where connections are long-lived, and not a problem with this
mechanism per se. Servers MAY unilaterally disconnect clients in mechanism per se. Servers MAY unilaterally disconnect clients in
accordance with the application protocol. accordance with the application protocol.
An OAuth credential is not equivalent to the password or primary An OAuth credential is not equivalent to the password or primary
account credential. There are protocols like XMPP that allow actions account credential. There are protocols like XMPP that allow actions
like change password. The server SHOULD ensure that actions taken in like change password. The server SHOULD ensure that actions taken in
the authenticated channel are appropriate to the strength of the the authenticated channel are appropriate to the strength of the
presented credential. presented credential.
It is possible for an application server running on Evil.example.com Tokens have a lifetime associated with them. Reducing the lifetime
to tell a client to request a token from Good.example.org. A client of a token provides security benefits in case that tokens leak. In
following these instructions will pass a token from Good to Evil. addition a previously obtained token MAY be revoked or rendered
This is by design, since it is possible that Good and Evil are merely invalid at any time. The client MAY request a new access token for
names, not descriptive, and that this is an innocuous activity each connection to a resource server, but it SHOULD cache and re-use
between cooperating two servers in different domains. For instance, access credentials that appear to be valid.
a site might operate their authentication service in-house, but
outsource their mail systems to an external entity.
Tokens have a lifetime associated with them. Reducing both the
lifetime of a token provides security benefits in case that tokens
leak. In addition a previously obtained token MAY be revoked or
rendered invalid at any time. The client MAY request a new access
token for each connection to a resource server, but it SHOULD cache
and re-use access credentials that appear to be valid.
7. IANA Considerations 7. IANA Considerations
7.1. SASL Registration 7.1. SASL Registration
The IANA is requested to register the following SASL profile: The IANA is requested to register the following SASL profile:
SASL mechanism profile: OAUTH SASL mechanism profile: OAUTH
Security Considerations: See this document Security Considerations: See this document
skipping to change at page 19, line 44 skipping to change at page 18, line 5
Note: None Note: None
7.2. GSS-API Registration 7.2. GSS-API Registration
IANA is further requested to assign an OID for this GSS mechanism in IANA is further requested to assign an OID for this GSS mechanism in
the SMI numbers registry, with the prefix of the SMI numbers registry, with the prefix of
iso.org.dod.internet.security.mechanisms (1.3.6.1.5.5) and to iso.org.dod.internet.security.mechanisms (1.3.6.1.5.5) and to
reference this specification in the registry. reference this specification in the registry.
7.3. Link Type Registration
Pursuant to [RFC5988] The following link type registrations [[will
be]] registered by mail to link-relations@ietf.org.
7.3.1. OAuth 2 Authentication Endpoint
o Relation Name: oauth2-authenticator
o Description: An OAuth 2.0 authentication endpoint.
o Reference:
o Notes: This link type indicates an OAuth 2.0 authentication
endpoint that can be used for user authentication/authorization
for the endpoint providing the link.
o Application Data: [optional]
7.3.2. OAuth 2 Token Endpoint
o Relation Name: oauth2-token
o Description: The OAuth token endpoint used to get tokens for
access.
o Reference:
o Notes: The OAuth 2.0 token endpoint to be used for obtaining
tokens to access the endpoint providing the link.
o Application Data: This link type has one link-extension "grant-
types", which is the OAuth 2.0 grant types that can be used at the
token endpoint to obtain a token. This is not an exclusive list,
it provides a hint to the application of what SHOULD be valid. A
token endpoint MAY support additional grant types not advertised
by a resource endpoint.
7.3.3. OAuth 1.0a Request Initiation Endpoint
o Relation Name: oauth-initiate
o Description: The OAuth 1.0a request initiation endpoint used to
get tokens for access.
o Reference:
o Notes: The OAuth 1.0a endpoint used to initiate the sequence, this
temporary request is what the user approves to grant access to the
resource.
o Application Data:
7.3.4. OAuth 1.0a Authorization Endpoint
o Relation Name: oauth-authorize
o Description: The OAuth 1.0a authorization endpoint used to approve
an access request.
o Reference:
o Notes:
o Application Data:
7.3.5. OAuth 1.0a Token Endpoint
o Relation Name: oauth-token
o Description: The OAuth 1.0a token endpoint used to get tokens for
access.
o Reference:
o Notes:
o Application Data:
8. Appendix A -- Document History 8. Appendix A -- Document History
[[ to be removed by RFC editor before publication as an RFC ]] [[ to be removed by RFC editor before publication as an RFC ]]
-04 -01
o Editorial clean-up and text in introduction improved.
o Added GSS-API support
-03
o Fixing channel binding, not tls-unique specific. Also defining
how the CB data is properly generated.
o Various small editorial changes and embarassing spelling fixes.
-02
o Filling out Channel Binding
o Added text clarifying how to bind to the 2 kinds of SASL o Ripping out discovery. Changed to refer to I-D.jones-appsawg-
identities. webfinger instead of WF and SWD older drafts.
-01 o Replacing HTTP as the message format and adjusted all examples.
o Bringing this into line with draft 12 of the core spec, the bearer -00
token spec, and references the MAC token spec
o Changing discovery over to using the Link header construct from o Renamed draft into proper IETF naming format now that it's
RFC5988. adopted.
o Added the seeds of channel binding. o Minor fixes.
-00 -00
o Initial revision o Initial revision
9. References 9. References
9.1. Normative References 9.1. Normative References
[I-D.ietf-oauth-v2] [I-D.ietf-oauth-v2]
Hammer-Lahav, E., Recordon, D., and D. Hardt, "The OAuth Hammer-Lahav, E., Recordon, D., and D. Hardt, "The OAuth
2.0 Authorization Protocol", draft-ietf-oauth-v2-22 (work 2.0 Authorization Framework", draft-ietf-oauth-v2-26 (work
in progress), September 2011. in progress), May 2012.
[I-D.ietf-oauth-v2-bearer] [I-D.ietf-oauth-v2-bearer]
Jones, M., Hardt, D., and D. Recordon, "The OAuth 2.0 Jones, M., Hardt, D., and D. Recordon, "The OAuth 2.0
Authorization Protocol: Bearer Tokens", Authorization Protocol: Bearer Tokens",
draft-ietf-oauth-v2-bearer-14 (work in progress), draft-ietf-oauth-v2-bearer-19 (work in progress),
November 2011. April 2012.
[I-D.ietf-oauth-v2-http-mac] [I-D.ietf-oauth-v2-http-mac]
Hammer-Lahav, E., Barth, A., and B. Adida, "HTTP Hammer-Lahav, E., "HTTP Authentication: MAC Access
Authentication: MAC Access Authentication", Authentication", draft-ietf-oauth-v2-http-mac-01 (work in
draft-ietf-oauth-v2-http-mac-00 (work in progress), progress), February 2012.
May 2011.
[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.
[RFC2234] Crocker, D., Ed. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", RFC 2234, November 1997.
[RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., [RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H.,
Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext
Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999. Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999.
[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.
[RFC2743] Linn, J., "Generic Security Service Application Program [RFC2743] Linn, J., "Generic Security Service Application Program
Interface Version 2, Update 1", RFC 2743, January 2000. Interface Version 2, Update 1", RFC 2743, January 2000.
[RFC3174] Eastlake, D. and P. Jones, "US Secure Hash Algorithm 1 [RFC3174] Eastlake, D. and P. Jones, "US Secure Hash Algorithm 1
(SHA1)", RFC 3174, September 2001. (SHA1)", RFC 3174, September 2001.
[RFC4422] Melnikov, A. and K. Zeilenga, "Simple Authentication and [RFC4422] Melnikov, A. and K. Zeilenga, "Simple Authentication and
Security Layer (SASL)", RFC 4422, June 2006. Security Layer (SASL)", RFC 4422, June 2006.
[RFC4627] Crockford, D., "The application/json Media Type for
JavaScript Object Notation (JSON)", RFC 4627, July 2006.
[RFC5056] Williams, N., "On the Use of Channel Bindings to Secure [RFC5056] Williams, N., "On the Use of Channel Bindings to Secure
Channels", RFC 5056, November 2007. Channels", RFC 5056, November 2007.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security [RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246, August 2008. (TLS) Protocol Version 1.2", RFC 5246, August 2008.
[RFC5801] Josefsson, S. and N. Williams, "Using Generic Security [RFC5801] Josefsson, S. and N. Williams, "Using Generic Security
Service Application Program Interface (GSS-API) Mechanisms Service Application Program Interface (GSS-API) Mechanisms
in Simple Authentication and Security Layer (SASL): The in Simple Authentication and Security Layer (SASL): The
GS2 Mechanism Family", RFC 5801, July 2010. GS2 Mechanism Family", RFC 5801, July 2010.
skipping to change at page 24, line 26 skipping to change at page 20, line 30
[RFC5988] Nottingham, M., "Web Linking", RFC 5988, October 2010. [RFC5988] Nottingham, M., "Web Linking", RFC 5988, October 2010.
[RFC6125] Saint-Andre, P. and J. Hodges, "Representation and [RFC6125] Saint-Andre, P. and J. Hodges, "Representation and
Verification of Domain-Based Application Service Identity Verification of Domain-Based Application Service Identity
within Internet Public Key Infrastructure Using X.509 within Internet Public Key Infrastructure Using X.509
(PKIX) Certificates in the Context of Transport Layer (PKIX) Certificates in the Context of Transport Layer
Security (TLS)", RFC 6125, March 2011. Security (TLS)", RFC 6125, March 2011.
9.2. Informative References 9.2. Informative References
[I-D.hammer-hostmeta] [I-D.jones-appsawg-webfinger]
Hammer-Lahav, E. and B. Cook, "Web Host Metadata", Jones, P., Salgueiro, G., and J. Smarr, "WebFinger",
draft-hammer-hostmeta-17 (work in progress), draft-jones-appsawg-webfinger-05 (work in progress),
September 2011. May 2012.
[I-D.jones-simple-web-discovery]
Jones, M. and Y. Goland, "Simple Web Discovery (SWD)",
draft-jones-simple-web-discovery-01 (work in progress),
July 2011.
[RFC3501] Crispin, M., "INTERNET MESSAGE ACCESS PROTOCOL - VERSION [RFC3501] Crispin, M., "INTERNET MESSAGE ACCESS PROTOCOL - VERSION
4rev1", RFC 3501, March 2003. 4rev1", RFC 3501, March 2003.
Authors' Addresses Authors' Addresses
William Mills William Mills
Yahoo! Inc. Yahoo! Inc.
Phone: Phone:
Email: wmills@yahoo-inc.com Email: wmills@yahoo-inc.com
Tim Showalter Tim Showalter
Yahoo! Inc.
Phone: Phone:
Email: timshow@yahoo-inc.com Email: tjs@psaux.com
Hannes Tschofenig Hannes Tschofenig
Nokia Siemens Networks Nokia Siemens Networks
Linnoitustie 6 Linnoitustie 6
Espoo 02600 Espoo 02600
Finland Finland
Phone: +358 (50) 4871445 Phone: +358 (50) 4871445
Email: Hannes.Tschofenig@gmx.net Email: Hannes.Tschofenig@gmx.net
URI: http://www.tschofenig.priv.at URI: http://www.tschofenig.priv.at
 End of changes. 73 change blocks. 
416 lines changed or deleted 237 lines changed or added

This html diff was produced by rfcdiff 1.41. The latest version is available from http://tools.ietf.org/tools/rfcdiff/