draft-ietf-kitten-sasl-oauth-22.txt		draft-ietf-kitten-sasl-oauth-23.txt
	KITTEN W. Mills		KITTEN W. Mills
	Internet-Draft Microsoft		Internet-Draft Microsoft
	Intended status: Standards Track T. Showalter		Intended status: Standards Track T. Showalter
	Expires: November 1, 2015		Expires: November 30, 2015
	H. Tschofenig		H. Tschofenig
	ARM Ltd.		ARM Ltd.
	April 30, 2015		May 29, 2015
	A set of SASL Mechanisms for OAuth		A set of SASL Mechanisms for OAuth
	draft-ietf-kitten-sasl-oauth-22.txt		draft-ietf-kitten-sasl-oauth-23.txt
	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 credentials		This document defines how an application client uses credentials
	obtained via OAuth over the Simple Authentication and Security Layer		obtained via OAuth over the Simple Authentication and Security Layer
	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 November 1, 2015.		This Internet-Draft will expire on November 30, 2015.
	Copyright Notice		Copyright Notice
	Copyright (c) 2015 IETF Trust and the persons identified as the		Copyright (c) 2015 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
	skipping to change at page 2, line 31		skipping to change at page 2, line 31
	Table of Contents		Table of Contents
	1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3		1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
	2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5		2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
	3. OAuth SASL Mechanism Specifications . . . . . . . . . . . . . 6		3. OAuth SASL Mechanism Specifications . . . . . . . . . . . . . 6
	3.1. Initial Client Response . . . . . . . . . . . . . . . . . 7		3.1. Initial Client Response . . . . . . . . . . . . . . . . . 7
	3.1.1. Reserved Key/Values . . . . . . . . . . . . . . . . . 8		3.1.1. Reserved Key/Values . . . . . . . . . . . . . . . . . 8
	3.2. Server's Response . . . . . . . . . . . . . . . . . . . . 8		3.2. Server's Response . . . . . . . . . . . . . . . . . . . . 8
	3.2.1. OAuth Identifiers in the SASL Context . . . . . . . . 9		3.2.1. OAuth Identifiers in the SASL Context . . . . . . . . 9
	3.2.2. Server Response to Failed Authentication . . . . . . 9		3.2.2. Server Response to Failed Authentication . . . . . . 9
	3.2.3. Completing an Error Message Sequence . . . . . . . . 10		3.2.3. Completing an Error Message Sequence . . . . . . . . 11
	3.3. OAuth Access Token Types using Keyed Message Digests . . 11		3.3. OAuth Access Token Types using Keyed Message Digests . . 11
	4. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 12		4. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 12
	4.1. Successful Bearer Token Exchange . . . . . . . . . . . . 12		4.1. Successful Bearer Token Exchange . . . . . . . . . . . . 12
	4.2. Successful OAuth 1.0a Token Exchange . . . . . . . . . . 13		4.2. Successful OAuth 1.0a Token Exchange . . . . . . . . . . 13
	4.3. Failed Exchange . . . . . . . . . . . . . . . . . . . . . 14		4.3. Failed Exchange . . . . . . . . . . . . . . . . . . . . . 14
	4.4. SMTP Example of a Failed Negotiation . . . . . . . . . . 15		4.4. SMTP Example of a Failed Negotiation . . . . . . . . . . 15
	5. Security Considerations . . . . . . . . . . . . . . . . . . . 16		5. Security Considerations . . . . . . . . . . . . . . . . . . . 16
	6. Internationalization Considerations . . . . . . . . . . . . . 17		6. Internationalization Considerations . . . . . . . . . . . . . 17
	7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17		7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17
	7.1. SASL Registration . . . . . . . . . . . . . . . . . . . . 17		7.1. SASL Registration . . . . . . . . . . . . . . . . . . . . 18
	8. References . . . . . . . . . . . . . . . . . . . . . . . . . 18		8. References . . . . . . . . . . . . . . . . . . . . . . . . . 18
	8.1. Normative References . . . . . . . . . . . . . . . . . . 18		8.1. Normative References . . . . . . . . . . . . . . . . . . 18
	8.2. Informative References . . . . . . . . . . . . . . . . . 19		8.2. Informative References . . . . . . . . . . . . . . . . . 19
	Appendix A. Acknowlegements . . . . . . . . . . . . . . . . . . 20		Appendix A. Acknowlegements . . . . . . . . . . . . . . . . . . 20
	Appendix B. Document History . . . . . . . . . . . . . . . . . . 20		Appendix B. Document History . . . . . . . . . . . . . . . . . . 20
	Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 23		Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 24
	1. Introduction		1. Introduction
	OAuth 1.0a [RFC5849] and OAuth 2.0 [RFC6749] are protocol frameworks		OAuth 1.0a [RFC5849] and OAuth 2.0 [RFC6749] are protocol frameworks
	that enable a third-party application to obtain limited access to a		that enable 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.
	The core OAuth 2.0 specification [RFC6749] specifies the interaction		The core OAuth 2.0 specification [RFC6749] specifies the interaction
	skipping to change at page 3, line 31		skipping to change at page 3, line 31
	[RFC5849].		[RFC5849].
	The main use cases for OAuth 2.0 and OAuth 1.0a have so far focused		The main use cases for OAuth 2.0 and OAuth 1.0a have so far focused
	on an HTTP-based [RFC7230] environment only. This document		on an HTTP-based [RFC7230] environment only. This document
	integrates OAuth 1.0a and OAuth 2.0 into non-HTTP-based applications		integrates OAuth 1.0a and OAuth 2.0 into non-HTTP-based applications
	using the integration into SASL. Hence, this document takes		using the integration into SASL. Hence, this document takes
	advantage of the OAuth protocol and its deployment base to provide a		advantage of the OAuth protocol and its deployment base to provide a
	way to use the Simple Authentication and Security Layer (SASL)		way to use the Simple Authentication and Security Layer (SASL)
	[RFC4422] to gain access to resources when using non-HTTP-based		[RFC4422] to gain access to resources when using non-HTTP-based
	protocols, such as the Internet Message Access Protocol (IMAP)		protocols, such as the Internet Message Access Protocol (IMAP)
	[RFC3501] and the Simple Mail Transfer Protocol (SMTP) [RFC5321],		[RFC3501] and the Simple Mail Transfer Protocol (SMTP) [RFC5321].
	which is what this memo uses in the examples.		This document gives examples of use in IMAP and SMTP.
	To illustrate the impact of integrating this specification into an		To illustrate the impact of integrating this specification into an
	OAuth-enabled application environment, Figure 1 shows the abstract		OAuth-enabled application environment, Figure 1 shows the abstract
	message flow of OAuth 2.0 [RFC6749]. As indicated in the figure,		message flow of OAuth 2.0 [RFC6749]. As indicated in the figure,
	this document impacts the exchange of messages (E) and (F) since SASL		this document impacts the exchange of messages (E) and (F) since SASL
	is used for interaction between the client and the resource server		is used for interaction between the client and the resource server
	instead of HTTP.		instead of HTTP.
	----+		----+
	+--------+ +---------------+ |		+--------+ +---------------+ |
	skipping to change at page 4, line 45		skipping to change at page 4, line 45
	existing authentication mechanisms and allows old protocols to make		existing authentication mechanisms and allows old protocols to make
	use of new authentication mechanisms. The framework also provides a		use of new authentication mechanisms. The framework also provides a
	protocol for securing subsequent exchanges within a data security		protocol for securing subsequent exchanges within a data security
	layer.		layer.
	When OAuth is integrated into SASL the high-level steps are as		When OAuth is integrated into SASL the high-level steps are as
	follows:		follows:
	(A) The client requests authorization from the resource owner.		(A) The client requests authorization from the resource owner.
	The authorization request can be made directly to the resource		The authorization request can be made directly to the resource
	owner (as shown), or preferably indirectly via the authorization		owner (as shown), or indirectly via the authorization server as an
	server as an intermediary.		intermediary.
	(B) The client receives an authorization grant which is a		(B) The client receives an authorization grant which is a
	credential representing the resource owner's authorization,		credential representing the resource owner's authorization,
	expressed using one of the grant types defined in [RFC6749] or		expressed using one of the grant types defined in [RFC6749] or
	[RFC5849] or using an extension grant type. The authorization		[RFC5849] or using an extension grant type. The authorization
	grant type depends on the method used by the client to request		grant type depends on the method used by the client to request
	authorization and the types supported by the authorization server.		authorization and the types supported by the authorization server.
	(C) The client requests an access token by authenticating with the		(C) The client requests an access token by authenticating with the
	authorization server and presenting the authorization grant.		authorization server and presenting the authorization grant.
	skipping to change at page 6, line 8		skipping to change at page 6, line 8
	"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and		"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
	"OPTIONAL" in this document are to be interpreted as described in		"OPTIONAL" in this document are to be interpreted as described in
	[RFC2119].		[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
	2.0 specification [RFC6749] and SASL [RFC4422].		2.0 specification [RFC6749] and SASL [RFC4422].
	In examples, "C:" and "S:" indicate lines sent by the client and		In examples, "C:" and "S:" indicate lines sent by the client and
	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, see		Note that the IMAP SASL specification requires base64 encoding, as
	Section 4 of [RFC4648], not this memo.		specified in Section 4 of [RFC4648].
	3. OAuth SASL Mechanism Specifications		3. OAuth SASL Mechanism Specifications
	SASL is used as an authentication framework in a variety of		SASL is used as an authentication framework in a variety of
	application layer protocols. This document defines the following		application layer protocols. This document defines the following
	SASL mechanisms for usage with OAuth:		SASL mechanisms for usage with OAuth:
	OAUTHBEARER: OAuth 2.0 bearer tokens, as described in [RFC6750].		OAUTHBEARER: OAuth 2.0 bearer tokens, as described in [RFC6750].
	RFC 6750 uses Transport Layer Security (TLS) [RFC5246] to		RFC 6750 uses Transport Layer Security (TLS) [RFC5246] to
	secure the protocol interaction between the client and the		secure the protocol interaction between the client and the
	resource server.		resource server.
	OAUTH10A: OAuth 1.0a MAC tokens (using the HMAC-SHA1 keyed		OAUTH10A: OAuth 1.0a MAC tokens (using the HMAC-SHA1 keyed
	message digest), as described in Section 3.4.2 of [RFC5849].		message digest), as described in Section 3.4.2 of [RFC5849].
	New extensions may be defined to add additional OAuth Access Token		New extensions may be defined to add additional OAuth Access Token
	Types. Such a new SASL OAuth mechanism can be added by simply		Types. Such a new SASL OAuth mechanism can be added by registering
	registering the new name(s) and citing this specification for the		the new name(s) with IANA in the SASL Mechanisms registry and citing
	further definition.		this specification for the further definition.
	SASL mechanisms using this document as their definition do not		SASL mechanisms using this document as their definition do not
	provide a data security layer; that is, they cannot provide integrity		provide a data security layer; that is, they cannot provide integrity
	or confidentiality protection for application messages after the		or confidentiality protection for application messages after the
	initial authentication. If such protection is needed, TLS or some		initial authentication. If such protection is needed, TLS or some
	similar solution should be used. Additionally, for the two		similar solution should be used. Additionally, for the two
	mechanisms specified in this document, TLS MUST be used for		mechanisms specified in this document, TLS MUST be used for
	OAUTHBEARER to protect the bearer token; for OAUTH10A the use of TLS		OAUTHBEARER to protect the bearer token; for OAUTH10A the use of TLS
	is RECOMMENDED.		is RECOMMENDED.
	skipping to change at page 8, line 12		skipping to change at page 8, line 12
	The following keys and corresponding values are defined in the client		The following keys and corresponding values are defined in the client
	response:		response:
	auth (REQUIRED): The payload that would be in the HTTP		auth (REQUIRED): The payload that would be in the HTTP
	Authorization header if this OAuth exchange was being carried		Authorization header if this OAuth exchange was being carried
	out over HTTP.		out over HTTP.
	host: Contains the host name to which the client connected. In		host: Contains the host name to which the client connected. In
	an HTTP context this is the value of the HTTP Host header.		an HTTP context this is the value of the HTTP Host header.
	port: Contains the port number represented as a decimal positive		port: Contains the destination port that the client connected to,
	integer string without leading zeros to which the client		represented as a decimal positive integer string without
	connected.		leading zeros.
	For OAuth token types such as OAuth 1.0a that use keyed message		For OAuth token types such as OAuth 1.0a that use keyed message
	digests the client MUST send host and port number key/values, and the		digests the client MUST send host and port number key/values, and the
	server MUST fail an authorization request requiring keyed message		server MUST fail an authorization request requiring keyed message
	digests that are not accompanied by host and port values. In OAuth		digests that are not accompanied by host and port values. In OAuth
	1.0a for example, the so-called "signature base string calculation"		1.0a for example, the so-called "signature base string calculation"
	includes the reconstructed HTTP URL.		includes the reconstructed HTTP URL.
	3.1.1. Reserved Key/Values		3.1.1. Reserved Key/Values
	skipping to change at page 8, line 37		skipping to change at page 8, line 37
	usage of these in the SASL context and extend this specification.		usage of these in the SASL context and extend this specification.
	For OAuth Access Token Types that include a keyed message digest of		For OAuth Access Token Types that include a keyed message digest of
	the request the default values MUST be used unless explicit values		the request the default values MUST be used unless explicit values
	are provided in the client response. The following key values are		are provided in the client response. The following key values are
	reserved for future use:		reserved for future use:
	mthd (RESERVED): HTTP method, the default value is "POST".		mthd (RESERVED): HTTP method, the default value is "POST".
	path (RESERVED): HTTP path data, the default value is "/".		path (RESERVED): HTTP path data, the default value is "/".
	post (RESERVED): HTTP post data, the default value is "".		post (RESERVED): HTTP post data, the default value is the empty
			string ("").
	qs (RESERVED): The HTTP query string, the default value is "".		qs (RESERVED): The HTTP query string, the default value is the
			empty string ("").
	3.2. Server's Response		3.2. Server's Response
	The server validates the response according the specification for the		The server validates the response according to the specification for
	OAuth Access Token Types used. If the OAuth Access Token Type		the OAuth Access Token Types used. If the OAuth Access Token Type
	utilizes a keyed message digest of the request parameters then the		utilizes a keyed message digest of the request parameters then the
	client must provide a client response that satisfies the data		client must provide a client response that satisfies the data
	requirements for the scheme in use.		requirements for the scheme in use.
	The server fully validates the client response before generating a		The server fully validates the client response before generating a
	server response; this will necessarily include the validation steps		server response; this will necessarily include the validation steps
	listed in the specification for the OAuth Access Token Type used.		listed in the specification for the OAuth Access Token Type used.
	However, additional validation steps may be needed, depending on the		However, additional validation steps may be needed, depending on the
	particular application protocol making use of SASL. In particular,		particular application protocol making use of SASL. In particular,
	values included as kvpairs in the client response (such as host and		values included as kvpairs in the client response (such as host and
	port) which correspond to values known to the application by some		port) which correspond to values known to the application server by
	other mechanism (such as an application protocol data unit or pre-		some other mechanism (such as an application protocol data unit or
	configured values) MUST be validated to match between the initial		pre-configured values) MUST be validated to match between the initial
	client response and the the other source(s) of such information. As		client response and the the other source(s) of such information. As
	a concrete example, when SASL is used over IMAP to an IMAP server for		a concrete example, when SASL is used over IMAP to an IMAP server for
	a single domain the hostname can be vaialble via configuration; this		a single domain the hostname can be available via configuration; this
	hostname must be validated to match the value sent in the 'host'		hostname must be validated to match the value sent in the 'host'
	kvpair.		kvpair.
	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 authenticated identity reported		completing the SASL negotiation. The authenticated identity reported
	by the SASL mechanism is the identity securely established for the		by the SASL mechanism is the identity securely established for the
	client with the OAuth credential. The application, not the SASL		client with the OAuth credential. The application, not the SASL
	mechanism, based on local access policy determines whether the		mechanism, based on local access policy determines whether the
	identity reported by the mechanism is allowed access to the requested		identity reported by the mechanism is allowed access to the requested
	resource. Note that the semantics of the authzid is specified by the		resource. Note that the semantics of the authzid is specified by the
	skipping to change at page 10, line 8		skipping to change at page 10, line 8
	formatted error result, and fails the authentication. The error		formatted error result, and fails the authentication. The error
	result consists of the following values:		result consists of the following values:
	status (REQUIRED): The authorization error code. Valid error		status (REQUIRED): The authorization error code. Valid error
	codes are defined in the IANA "OAuth Extensions Error Registry"		codes are defined in the IANA "OAuth Extensions Error Registry"
	specified in the OAuth 2 core specification.		specified in the OAuth 2 core specification.
	scope (OPTIONAL): An OAuth scope which is valid to access the		scope (OPTIONAL): An OAuth scope which is valid to access the
	service. This may be omitted which implies that unscoped		service. This may be omitted which implies that unscoped
	tokens are required. If a scope is specified then a single		tokens are required. If a scope is specified then a single
	scope is preferred, use of a space separated list of scopes is		scope is preferred. At the time this document was written
	NOT RECOMMENDED.		there are several implementations that do not properly support
			space separated lists of scopes, so the use of a space
			separated list of scopes is NOT RECOMMENDED.
	openid-configuration (OPTIONAL): The URL for a document following		openid-configuration (OPTIONAL): The URL for a document following
	the OpenID Provider Configuration Information schema as		the OpenID Provider Configuration Information schema as
	described in OpenID Connect Discovery (OIDCD)		described in OpenID Connect Discovery (OIDCD)
	[OpenID.Discovery] section 3 that is appropriate for the user.		[OpenID.Discovery] section 3 that is appropriate for the user.
	As specified in OIDCD this will have the "https" URL scheme.		As specified in OIDCD this will have the "https" URL scheme.
	This document MUST have all OAuth related data elements		This document MUST have all OAuth related data elements
	populated. The server MAY return different URLs for users in		populated. The server MAY return different URLs for users in
	different domains and the client SHOULD NOT cache a single		different domains and the client SHOULD NOT cache a single
	returned value and assume it applies for all users/domains that		returned value and assume it applies for all users/domains that
	skipping to change at page 12, line 30		skipping to change at page 12, line 35
	then STARTTLS MUST be used as TLS is required in the Bearer Token		then STARTTLS MUST be used as TLS is required in the Bearer Token
	specification.		specification.
	Note to implementers: The SASL OAuth method names are case		Note to implementers: The SASL OAuth method names are case
	insensitive. One example uses "Bearer" but that could as easily be		insensitive. One example uses "Bearer" but that could as easily be
	"bearer", "BEARER", or "BeArEr".		"bearer", "BEARER", or "BeArEr".
	4.1. Successful Bearer Token Exchange		4.1. Successful Bearer Token Exchange
	This example shows a successful OAuth 2.0 bearer token exchange in		This example shows a successful OAuth 2.0 bearer token exchange in
	IMAP. Note that line breaks are inserted for readability. The		IMAP. Note that line breaks are inserted for readability.
	underlying TLS establishment is not shown but is required for using
	Bearer Tokens per that specification.
			[Initial connection and TLS establishment...]
	S: * OK IMAP4rev1 Server Ready		S: * OK IMAP4rev1 Server Ready
	C: t0 CAPABILITY		C: t0 CAPABILITY
	S: * CAPABILITY IMAP4rev1 AUTH=OAUTHBEARER SASL-IR		S: * CAPABILITY IMAP4rev1 AUTH=OAUTHBEARER SASL-IR
	S: t0 OK Completed		S: t0 OK Completed
	C: t1 AUTH OAUTHBEARER bixhPXVzZXJAZXhhbXBsZS5jb20sAWhvc3Q9c2Vy		C: t1 AUTH OAUTHBEARER bixhPXVzZXJAZXhhbXBsZS5jb20sAWhvc3Q9c2Vy
	dmVyLmV4YW1wbGUuY29tAXBvcnQ9MTQzAWF1dGg9QmVhcmVyIHZGOWRmd		dmVyLmV4YW1wbGUuY29tAXBvcnQ9MTQzAWF1dGg9QmVhcmVyIHZGOWRmd
	DRxbVRjMk52YjNSbGNrQmhiSFJoZG1semRHRXVZMjl0Q2c9PQEB		DRxbVRjMk52YjNSbGNrQmhiSFJoZG1semRHRXVZMjl0Q2c9PQEB
	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 (with %x01 represented as ^A and long		decoded initial client response (with %x01 represented as ^A and long
	lines wrapped for readability) is:		lines wrapped for readability) is:
	n,a=user@example.com,^Ahost=server.example.com^Aport=143^A		n,a=user@example.com,^Ahost=server.example.com^Aport=143^A
	auth=Bearer vF9dft4qmTc2Nvb3RlckBhbHRhdmlzdGEuY29tCg==^A^A		auth=Bearer vF9dft4qmTc2Nvb3RlckBhbHRhdmlzdGEuY29tCg==^A^A
			The same credential used in an SMTP exchange is shown below. Again
	The same credential used in an SMTP exchange is shown below. Note		this example assumes that TLS is already established per the Bearer
	that line breaks are inserted for readability, and that the SMTP		Token specification requirements.
	protocol terminates lines with CR and LF characters (ASCII values
	0x0D and 0x0A), these are not displayed explicitly in the example.
	Again this example assumes that TLS is already established per the
	Bearer Token specification requirements.
	[connection begins]		[connection begins]
	S: 220 mx.example.com ESMTP 12sm2095603fks.9		S: 220 mx.example.com ESMTP 12sm2095603fks.9
	C: EHLO sender.example.com		C: EHLO sender.example.com
	S: 250-mx.example.com at your service,[172.31.135.47]		S: 250-mx.example.com at your service,[172.31.135.47]
	S: 250-SIZE 35651584		S: 250-SIZE 35651584
	S: 250-8BITMIME		S: 250-8BITMIME
	S: 250-AUTH LOGIN PLAIN OAUTHBEARER		S: 250-AUTH LOGIN PLAIN OAUTHBEARER
	S: 250-ENHANCEDSTATUSCODES		S: 250-ENHANCEDSTATUSCODES
	S: 250-STARTTLS		S: 250-STARTTLS
	S: 250 PIPELINING		S: 250 PIPELINING
	[Negotiate TLS...]		[Negotiate TLS...]
	C: t1 AUTH OAUTHBEARER bixhPXVzZXJAZXhhbXBsZS5jb20sAWhvc3Q9c2Vy		C: t1 AUTH OAUTHBEARER bixhPXVzZXJAZXhhbXBsZS5jb20sAWhvc3Q9c2Vy
	dmVyLmV4YW1wbGUuY29tAXBvcnQ9MTQzAWF1dGg9QmVhcmVyIHZGOWRmd		dmVyLmV4YW1wbGUuY29tAXBvcnQ9NTg3AWF1dGg9QmVhcmVyIHZGOWRmd
	DRxbVRjMk52YjNSbGNrQmhiSFJoZG1semRHRXVZMjl0Q2c9PQEB		DRxbVRjMk52YjNSbGNrQmhiSFJoZG1semRHRXVZMjl0Q2c9PQEB
	S: 235 Authentication successful.		S: 235 Authentication successful.
	[connection continues...]		[connection continues...]
			The decoded initial client response is:
			n,a=user@example.com,^Ahost=server.example.com^Aport=587^A
			auth=Bearer vF9dft4qmTc2Nvb3RlckBhbHRhdmlzdGEuY29tCg==^A^A
	4.2. Successful OAuth 1.0a Token Exchange		4.2. Successful OAuth 1.0a Token Exchange
	This IMAP example shows a successful OAuth 1.0a token exchange. Note		This IMAP example shows a successful OAuth 1.0a token exchange. Note
	that line breaks are inserted for readability. This example assumes		that line breaks are inserted for readability. This example assumes
	that TLS is already established. Signature computation is discussed		that TLS is already established. Signature computation is discussed
	in Section 3.3.		in Section 3.3.
	S: * OK IMAP4rev1 Server Ready		S: * OK IMAP4rev1 Server Ready
	C: t0 CAPABILITY		C: t0 CAPABILITY
	S: * CAPABILITY IMAP4rev1 AUTH=OAUTHBEARER OAUTH10A SASL-IR		S: * CAPABILITY IMAP4rev1 AUTH=OAUTHBEARER OAUTH10A SASL-IR
	skipping to change at page 15, line 20		skipping to change at page 15, line 22
	hvc3Q9c2VydmVyLmV4YW1wbGUuY29tAXBvcnQ9MTQzAWF1dGg9AQE=		hvc3Q9c2VydmVyLmV4YW1wbGUuY29tAXBvcnQ9MTQzAWF1dGg9AQE=
	S: + eyJzdGF0dXMiOiJpbnZhbGlkX3Rva2VuIiwic2NvcGUiOiJleGFtcGxl		S: + eyJzdGF0dXMiOiJpbnZhbGlkX3Rva2VuIiwic2NvcGUiOiJleGFtcGxl
	X3Njb3BlIiwib3BlbmlkLWNvbmZpZ3VyYXRpb24iOiJodHRwczovL2V4		X3Njb3BlIiwib3BlbmlkLWNvbmZpZ3VyYXRpb24iOiJodHRwczovL2V4
	YW1wbGUuY29tLy53ZWxsLWtub3duL29wZW5pZC1jb25maWd1cmF0aW9u		YW1wbGUuY29tLy53ZWxsLWtub3duL29wZW5pZC1jb25maWd1cmF0aW9u
	In0=		In0=
	C: *		C: *
	S: t1 NO SASL authentication failed		S: t1 NO SASL authentication failed
	4.4. SMTP Example of a Failed Negotiation		4.4. SMTP Example of a Failed Negotiation
	This example shows an authorization failure in an SMTP exchange.		This example shows an authorization failure in an SMTP exchange. TLS
	Note that line breaks are inserted for readability, and that the SMTP		negotiation is not shown but as noted above it is required for the
	protocol terminates lines with CR and LF characters (ASCII values		use of Bearer Tokens.
	0x0D and 0x0A), these are not displayed explicitly in the example.
	TLS negotiation is not shown but as noted above it is required for
	the use of Bearer Tokens.
	[connection begins]		[connection begins]
	S: 220 mx.example.com ESMTP 12sm2095603fks.9		S: 220 mx.example.com ESMTP 12sm2095603fks.9
	C: EHLO sender.example.com		C: EHLO sender.example.com
	S: 250-mx.example.com at your service,[172.31.135.47]		S: 250-mx.example.com at your service,[172.31.135.47]
	S: 250-SIZE 35651584		S: 250-SIZE 35651584
	S: 250-8BITMIME		S: 250-8BITMIME
	S: 250-AUTH LOGIN PLAIN OAUTHBEARER		S: 250-AUTH LOGIN PLAIN OAUTHBEARER
	S: 250-ENHANCEDSTATUSCODES		S: 250-ENHANCEDSTATUSCODES
	S: 250 PIPELINING		S: 250 PIPELINING
			[Negotiate TLS...]
	C: AUTH OAUTHBEARER bix1c2VyPXNvbWV1c2VyQGV4YW1wbGUuY29tLAFhdXRoPUJlYXJl		C: AUTH OAUTHBEARER bix1c2VyPXNvbWV1c2VyQGV4YW1wbGUuY29tLAFhdXRoPUJlYXJl
	ciB2RjlkZnQ0cW1UYzJOdmIzUmxja0JoZEhSaGRtbHpkR0V1WTI5dENnPT0BAQ==		ciB2RjlkZnQ0cW1UYzJOdmIzUmxja0JoZEhSaGRtbHpkR0V1WTI5dENnPT0BAQ==
	S: 334 eyJzdGF0dXMiOiJpbnZhbGlkX3Rva2VuIiwic2NoZW1lcyI6ImJlYXJlciBtYWMiL		S: 334 eyJzdGF0dXMiOiJpbnZhbGlkX3Rva2VuIiwic2NoZW1lcyI6ImJlYXJlciBtYWMiL
	CJzY29wZSI6Imh0dHBzOi8vbWFpbC5nb29nbGUuY29tLyJ9		CJzY29wZSI6Imh0dHBzOi8vbWFpbC5leGFtcGxlLmNvbS8ifQ==
	C: AQ==		C: AQ==
	S: 535-5.7.1 Username and Password not accepted. Learn more at		S: 535-5.7.1 Username and Password not accepted. Learn more at
	S: 535 5.7.1 http://support.example.com/mail/oauth		S: 535 5.7.1 http://support.example.com/mail/oauth
	[connection continues...]		[connection continues...]
			The initial client response is:
			n,user=someuser@example.com,^A
			auth=Bearer vF9dft4qmTc2Nvb3RlckBhdHRhdmlzdGEuY29tCg==^A^A
	The server returned an error message in the 334 SASL message, the		The server returned an error message in the 334 SASL message, the
	client responds with the required dummy response, and the server		client responds with the required dummy response, and the server
	finalizes the negotiation.		finalizes the negotiation.
			{
			"status":"invalid_token",
			"schemes":"bearer mac",
			"scope":"https://mail.example.com/"
			}
	5. Security Considerations		5. Security Considerations
	OAuth 1.0a and OAuth 2 allow for a variety of deployment scenarios,		OAuth 1.0a and OAuth 2 allow for a variety of deployment scenarios,
	and the security properties of these profiles vary. As shown in		and the security properties of these profiles vary. As shown in
	Figure 1 this specification is aimed to be integrated into a larger		Figure 1 this specification is aimed to be integrated into a larger
	OAuth deployment. Application developers therefore need to		OAuth deployment. Application developers therefore need to
	understand their security requirements based on a threat assessment		understand their security requirements based on a threat assessment
	before selecting a specific SASL OAuth mechanism. For OAuth 2.0 a		before selecting a specific SASL OAuth mechanism. For OAuth 2.0 a
	detailed security document [RFC6819] provides guidance to select		detailed security document [RFC6819] provides guidance to select
	those OAuth 2.0 components that help to mitigate threats for a given		those OAuth 2.0 components that help to mitigate threats for a given
	skipping to change at page 16, line 47		skipping to change at page 17, line 8
	Additionally, the following aspects are worth pointing out:		Additionally, the following aspects are worth pointing out:
	An access token is not equivalent to the user's long term password.		An access token is not equivalent to the user's long term password.
	Care has to be taken when these OAuth credentials are used for		Care has to be taken when these OAuth credentials are used for
	actions like changing passwords (as it is possible with some		actions like changing passwords (as it is possible with some
	protocols, e.g., XMPP [RFC6120]). The resource server should		protocols, e.g., XMPP [RFC6120]). The resource server should
	ensure that actions taken in the authenticated channel are		ensure that actions taken in the authenticated channel are
	appropriate to the strength of the presented credential.		appropriate to the strength of the presented credential.
	Lifetime of the appliation sessions.		Lifetime of the application sessions.
	It is possible that SASL will be authenticating a connection and		It is possible that SASL will be used to authenticate a connection
	the life of that connection may outlast the life of the access		and the life of that connection may outlast the life of the access
	token used to establish it. This is a common problem in		token used to establish it. This is a common problem in
	application protocols where connections are long-lived, and not a		application protocols where connections are long-lived, and not a
	problem with this mechanism per se. Resource servers may		problem with this mechanism per se. Resource servers may
	unilaterally disconnect clients in accordance with the application		unilaterally disconnect clients in accordance with the application
	protocol.		protocol.
	Access tokens have a lifetime.		Access tokens have a lifetime.
	Reducing the lifetime of an access token provides security		Reducing the lifetime of an access token provides security
	benefits and OAuth 2.0 introduces refresh tokens to obtain new		benefits and OAuth 2.0 introduces refresh tokens to obtain new
	skipping to change at page 18, line 29		skipping to change at page 18, line 44
	Intended usage: common		Intended usage: common
	Owner/Change controller: the IESG		Owner/Change controller: the IESG
	Note: None		Note: None
	8. References		8. References
	8.1. Normative References		8.1. Normative References
			[I-D.ietf-oauth-dyn-reg]
			Richer, J., Jones, M., Bradley, J., Machulak, M., and P.
			Hunt, "OAuth 2.0 Dynamic Client Registration Protocol",
			draft-ietf-oauth-dyn-reg-27 (work in progress), March
			2015.
	[OpenID.Core]		[OpenID.Core]
	Sakimura, N., Bradley, J., Jones, M., de Medeiros, B., and		Sakimura, N., Bradley, J., Jones, M., de Medeiros, B., and
	C. Mortimore, "OpenID Connect Core 1.0", February 2014.		C. Mortimore, "OpenID Connect Core 1.0", February 2014.
	[OpenID.Discovery]		[OpenID.Discovery]
	Sakimura, N., Bradley, J., Jones, M., and E. Jay, "OpenID		Sakimura, N., Bradley, J., Jones, M., and E. Jay, "OpenID
	Connect Discovery 1.0", July 2011.		Connect Discovery 1.0", July 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.
	skipping to change at page 19, line 24		skipping to change at page 19, line 47
	6749, October 2012.		6749, October 2012.
	[RFC6750] Jones, M. and D. Hardt, "The OAuth 2.0 Authorization		[RFC6750] Jones, M. and D. Hardt, "The OAuth 2.0 Authorization
	Framework: Bearer Token Usage", RFC 6750, October 2012.		Framework: Bearer Token Usage", RFC 6750, October 2012.
	[RFC7159] Bray, T., "The JavaScript Object Notation (JSON) Data		[RFC7159] Bray, T., "The JavaScript Object Notation (JSON) Data
	Interchange Format", RFC 7159, March 2014.		Interchange Format", RFC 7159, March 2014.
	8.2. Informative References		8.2. Informative References
	[I-D.ietf-oauth-dyn-reg]
	Richer, J., Jones, M., Bradley, J., Machulak, M., and P.
	Hunt, "OAuth 2.0 Dynamic Client Registration Protocol",
	draft-ietf-oauth-dyn-reg-27 (work in progress), March
	2015.
	[I-D.ietf-oauth-json-web-token]		[I-D.ietf-oauth-json-web-token]
	Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token		Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token
	(JWT)", draft-ietf-oauth-json-web-token-32 (work in		(JWT)", draft-ietf-oauth-json-web-token-32 (work in
	progress), December 2014.		progress), December 2014.
	[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.
	[RFC4959] Siemborski, R. and A. Gulbrandsen, "IMAP Extension for		[RFC4959] Siemborski, R. and A. Gulbrandsen, "IMAP Extension for
	Simple Authentication and Security Layer (SASL) Initial		Simple Authentication and Security Layer (SASL) Initial
	skipping to change at page 20, line 27		skipping to change at page 20, line 44
	Williams, Matt Miller, and Benjamin Kaduk.		Williams, Matt Miller, and Benjamin Kaduk.
	This document was produced under the chairmanship of Alexey Melnikov,		This document was produced under the chairmanship of Alexey Melnikov,
	Tom Yu, Shawn Emery, Josh Howlett, Sam Hartman. The supervising area		Tom Yu, Shawn Emery, Josh Howlett, Sam Hartman. The supervising area
	director was Stephen Farrell.		director was Stephen Farrell.
	Appendix B. Document History		Appendix B. Document History
	[[ to be removed by RFC editor before publication as an RFC ]]		[[ to be removed by RFC editor before publication as an RFC ]]
			-23
			o AD feedback from IESG review and comments.
			o Fixed port number in SMTP examples.
			o Minor editorial changes.
			o Dyn-Reg draft becomes normative.
			o Added explicit TLS start indicator in all examples, removed text
			that said we assume that.
	-19		-19
	o Last call feedback agaiun.		o Last call feedback agaiun.
	o Clarified usage of TLS in examples and fixed them some more.		o Clarified usage of TLS in examples and fixed them some more.
	Adding reference to RFC4422 and cancellation token and an example		Adding reference to RFC4422 and cancellation token and an example
	for that.		for that.
	-18		-18
End of changes. 33 change blocks.
	56 lines changed or deleted		81 lines changed or added
This html diff was produced by rfcdiff 1.42. The latest version is available from http://tools.ietf.org/tools/rfcdiff/