draft-ietf-kitten-sasl-oauth-11.txt   draft-ietf-kitten-sasl-oauth-12.txt 
KITTEN W. Mills KITTEN W. Mills
Internet-Draft Yahoo! Inc. Internet-Draft Yahoo! Inc.
Intended status: Standards Track T. Showalter Intended status: Standards Track T. Showalter
Expires: April 20, 2014 Expires: June 18, 2014
H. Tschofenig H. Tschofenig
Nokia Solutions and Networks Nokia Solutions and Networks
October 17, 2013 December 15, 2013
A set of SASL Mechanisms for OAuth A set of SASL Mechanisms for OAuth
draft-ietf-kitten-sasl-oauth-11.txt draft-ietf-kitten-sasl-oauth-12.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
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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 April 20, 2014. This Internet-Draft will expire on June 18, 2014.
Copyright Notice Copyright Notice
Copyright (c) 2013 IETF Trust and the persons identified as the Copyright (c) 2013 IETF Trust and the persons identified as the
document authors. All rights reserved. document authors. All rights reserved.
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described in the Simplified BSD License. described in the Simplified BSD License.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. OAuth SASL Mechanism Specifications . . . . . . . . . . . . . 5 3. OAuth SASL Mechanism Specifications . . . . . . . . . . . . . 6
3.1. Initial Client Response . . . . . . . . . . . . . . . . . 7 3.1. Initial Client Response . . . . . . . . . . . . . . . . . 7
3.1.1. Reserved Key/Values . . . . . . . . . . . . . . . . . 7 3.1.1. Reserved Key/Values . . . . . . . . . . . . . . . . . 7
3.2. Server's Response . . . . . . . . . . . . . . . . . . . . 8 3.2. Server's Response . . . . . . . . . . . . . . . . . . . . 8
3.2.1. OAuth Identifiers in the SASL Context . . . . . . . . 8 3.2.1. OAuth Identifiers in the SASL Context . . . . . . . . 8
3.2.2. Server Response to Failed Authentication . . . . . . 9 3.2.2. Server Response to Failed Authentication . . . . . . 8
3.2.3. Completing an Error Message Sequence . . . . . . . . 9 3.2.3. Completing an Error Message Sequence . . . . . . . . 9
3.3. OAuth Access Token Types using Keyed Message Digests . . 9 3.3. OAuth Access Token Types using Keyed Message Digests . . 9
3.4. Channel Binding . . . . . . . . . . . . . . . . . . . . . 10 4. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 10
4. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . 11
4.1. Successful Bearer Token Exchange . . . . . . . . . . . . 11 4.1. Successful Bearer Token Exchange . . . . . . . . . . . . 11
4.2. OAuth 1.0a Authorization with Channel Binding . . . . . . 12 4.2. Failed Exchange . . . . . . . . . . . . . . . . . . . . . 11
4.3. Failed Exchange . . . . . . . . . . . . . . . . . . . . . 13 4.3. SMTP Example of a Failed Negotiation . . . . . . . . . . 12
4.4. Failed Channel Binding . . . . . . . . . . . . . . . . . 14 5. Security Considerations . . . . . . . . . . . . . . . . . . . 13
4.5. SMTP Example of a Failed Negotiation . . . . . . . . . . 14 6. Internationalization Considerations . . . . . . . . . . . . . 14
5. Security Considerations . . . . . . . . . . . . . . . . . . . 15 7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14
6. Internationalization Considerations . . . . . . . . . . . . . 16 7.1. SASL Registration . . . . . . . . . . . . . . . . . . . . 14
7. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 17 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 15
7.1. SASL Registration . . . . . . . . . . . . . . . . . . . . 17 8.1. Normative References . . . . . . . . . . . . . . . . . . 15
8. References . . . . . . . . . . . . . . . . . . . . . . . . . 18 8.2. Informative References . . . . . . . . . . . . . . . . . 16
8.1. Normative References . . . . . . . . . . . . . . . . . . 18 Appendix A. Acknowlegements . . . . . . . . . . . . . . . . . . 16
8.2. Informative References . . . . . . . . . . . . . . . . . 19 Appendix B. Document History . . . . . . . . . . . . . . . . . . 16
Appendix A. Acknowlegements . . . . . . . . . . . . . . . . . . 19 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 19
Appendix B. Document History . . . . . . . . . . . . . . . . . . 19
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 22
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
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Note that the IMAP SASL specification requires base64 encoding, see Note that the IMAP SASL specification requires base64 encoding, see
Section 4 of [RFC4648], not this memo. Section 4 of [RFC4648], not this memo.
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) to secure the RFC 6750 uses Transport Layer Security (TLS) to secure the
protocol interaction between the client and the resource protocol interaction between the client and the resource
server. 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].
OAUTH10A-PLUS: Adds channel binding [RFC5056] capability to
OAUTH10A for protection against man-in-the-middle attacks.
OAUTH10A-PLUS mandates the usage of Transport Layer Security
(TLS).
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 simply
registering the new name(s) and citing this specification for the registering the new name(s) and citing this specification for the
further definition. New channel binding enabled "-PLUS" mechanisms further definition.
defined in this way MUST include message integrity protection.
These mechanisms are client initiated and lock-step, the server These mechanisms are client initiated and lock-step, the server
always replying to a client message. In the case where the client always replying to a client message. In the case where the client
has and correctly uses a valid token the flow is: has and correctly uses a valid token the flow is:
o Client sends a valid and correct initial client response. o Client sends a valid and correct initial client response.
o Server responds with a successful authentication. o Server responds with a successful authentication.
In the case where authorization fails the server sends an error In the case where authorization fails the server sends an error
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kvsep = %x01 kvsep = %x01
key = 1*ALPHA key = 1*ALPHA
value = *(VCHAR / SP / HTAB / CR / LF ) value = *(VCHAR / SP / HTAB / CR / LF )
kvpair = key "=" value kvsep kvpair = key "=" value kvsep
client_resp = 0*kvpair kvsep client_resp = 0*kvpair kvsep
The following key/value pairs are defined in the client response: The following key/value pairs are defined in the client response:
auth (REQUIRED): The payload of the HTTP Authorization header for auth (REQUIRED): The payload of the HTTP Authorization header for
an equivalent HTTP OAuth authorization. an equivalent HTTP OAuth authorization.
host: Contains the host name to which the client connected. host: Contains the host name to which the client connected.
port: Contains the port number represented as a decimal positive port: Contains the port number represented as a decimal positive
integer string without leading zeros to which the client integer string without leading zeros to which the client
connected. connected.
qs: The HTTP query string. In non-channel binding mechanisms qs: The HTTP query string. This is reserved for future use, the
this is reserved, the client SHOUD NOT send it, and has the client SHOUD NOT send it, and has the default value of "".
default value of "". In "-PLUS" variants this carries a
single key value pair "cbdata" for the channel binding data
payload formatted as an HTTP query string.
For OAuth token types that use keyed message digests the client MUST For OAuth token types that use keyed message digests the client MUST
send host and port number key/values, and the server MUST fail an send host and port number key/values, and the server MUST fail an
authorization request requiring keyed message digests that do not authorization request requiring keyed message digests that do not
have host and port values. In OAuth 1.0a for example, the so-called have host and port values. In OAuth 1.0a for example, the so-called
"signature base string calculation" includes the reconstructed HTTP "signature base string calculation" includes the reconstructed HTTP
URL. URL.
3.1.1. Reserved Key/Values 3.1.1. Reserved Key/Values
In these mechanisms values for path, query string and post body are In these mechanisms values for path, query string and post body are
assigned default values. OAuth authorization schemes MAY define assigned default values. OAuth authorization schemes MAY define
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 use request keyed message digest For OAuth Access Token Types that use request keyed message digest
the default values MUST be used unless explicit values are provided the default values MUST be used unless explicit values are provided
in the client response. The following key values are reserved for in the client response. The following key values are reserved for
future use: future use:
mthd (RESERVED): HTTP method, the default value is "POST". mthd (RESERVED): HTTP method, the default value is "POST".
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post (RESERVED): HTTP post data, the default value is "". post (RESERVED): HTTP post data, the default value is "".
3.2. Server's Response 3.2. Server's Response
The server validates the response per the specification for the OAuth The server validates the response per the specification for the OAuth
Access Token Types used. If the OAuth Access Token Type utilizes a Access Token Types used. If the OAuth Access Token Type utilizes a
keyed message digest of the request parameters then the client must keyed message digest of the request parameters then the client must
provide a client response that satisfies the data requirements for provide a client response that satisfies the data requirements for
the scheme in use. the scheme in use.
In a "-PLUS" mechanism the server examines the channel binding data,
extracts the channel binding unique prefix, and extracts the raw
channel biding data based on the channel binding type used. It then
computes it's own copy of the channel binding payload and compares
that to the payload sent by the client in the cbdata key/value.
Those two must be equal for 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 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 authz-id is specified by resource. Note that the semantics of the authz-id is specified by
the SASL framework [RFC4422]. the SASL framework [RFC4422].
3.2.1. OAuth Identifiers in the SASL Context 3.2.1. OAuth Identifiers in the SASL Context
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authorization server. OAuth access tokens may contain information authorization server. OAuth access tokens may contain information
about the authentication of the resource owner and about the client about the authentication of the resource owner and about the client
and may therefore make this information accessible to the resource and may therefore make this information accessible to the resource
server. server.
If both identifiers are needed by an application the developer will If both identifiers are needed by an application the developer will
need to provide a way to communicate that from the SASL mechanism need to provide a way to communicate that from the SASL mechanism
back to the application. back to the application.
3.2.2. Server Response to Failed Authentication 3.2.2. Server Response to Failed Authentication
For a failed authentication the server returns a JSON [RFC4627] For a failed authentication the server returns a JSON [RFC4627]
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 [[need registry name]] codes are defined in the IANA [[need registry name]] registry
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 empty which implies that unscoped service. This may be empty which implies that unscoped tokens
tokens are required, or a space separated list. Use of a are required, or a space separated list. Use of a space
space separated list is NOT RECOMMENDED. separated list is NOT RECOMMENDED.
If the resource server provides a scope then the client MUST always If the resource server provides a scope then the client MUST always
request scoped tokens from the token endpoint. If the resource request scoped tokens from the token endpoint. If the resource
server provides no scope to the client then the client SHOULD presume server provides no scope to the client then the client SHOULD presume
an empty scope (unscoped token) is needed. an empty scope (unscoped token) is needed.
If channel binding is in use and the channel binding fails the server 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 responds with a status code set to 412 to indicate that the channel
binding precondition failed. If the authentication scheme in use binding precondition failed. If the authentication scheme in use
does not include signing the server SHOULD revoke the presented does not include signing the server SHOULD revoke the presented
skipping to change at page 10, line 47 skipping to change at page 10, line 44
o The query string defaults to "". o The query string defaults to "".
In this example the signature base string with line breaks added for In this example the signature base string with line breaks added for
readability would be: readability would be:
POST&http%3A%2F%2Fexample.com:143%2F&oauth_consumer_key%3D9djdj82h4 POST&http%3A%2F%2Fexample.com:143%2F&oauth_consumer_key%3D9djdj82h4
8djs9d2%26oauth_nonce%3D7d8f3e4a%26oauth_signature_method%3DHMAC-SH 8djs9d2%26oauth_nonce%3D7d8f3e4a%26oauth_signature_method%3DHMAC-SH
A1%26oauth_timestamp%3D137131201%26oauth_token%3Dkkk9d7dh3k39sjv7 A1%26oauth_timestamp%3D137131201%26oauth_token%3Dkkk9d7dh3k39sjv7
3.4. Channel Binding
The channel binding data is carried in the "qs" (query string) key
value pair formatted as a standard HTTP query parameter with the name
"cbdata". Channel binding requires that the channel binding data be
integrity protected end-to-end in order to protect against man-in-
the-middle attacks. All SASL OAuth mechanisms with a "-PLUS" postfix
MUST provide integrity protection. It should be noted that while the
OAuth 2.0 Bearer Token mandates TLS it does not create keying
material at the application layer and is not suitable for use with
channel bindings.
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. For example, if the client
is using tls-unique for channel binding then the raw channel binding
data is the TLS finished message as specified in Section 3.1 of
[RFC5929].
4. Examples 4. Examples
These examples illustrate exchanges between an IMAP and SMTP clients These examples illustrate exchanges between an IMAP and SMTP clients
and servers. and servers.
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
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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
C: t1 AUTHENTICATE OAUTHBEARER bixhPXVzZXJAZXhhbXBsZS5jb20BaG9zdD1zZX C: t1 AUTHENTICATE OAUTHBEARER bixhPXVzZXJAZXhhbXBsZS5jb20BaG9zdD1zZX
J2ZXIuZXhhbXBsZS5jb20BcG9ydD0xNDMBYXV0aD1CZWFyZXIgdkY5ZGZ0NHFtV J2ZXIuZXhhbXBsZS5jb20BcG9ydD0xNDMBYXV0aD1CZWFyZXIgdkY5ZGZ0NHFtV
GMyTnZiM1JsY2tCaGJIUmhkbWx6ZEdFdVkyOXRDZz09AQE= GMyTnZiM1JsY2tCaGJIUmhkbWx6ZEdFdVkyOXRDZz09AQE=
S: 235 Authentication successful. S: 235 Authentication successful.
[connection continues...] [connection continues...]
4.2. OAuth 1.0a Authorization with Channel Binding 4.2. Failed Exchange
This example shows channel binding in the context of an OAuth 1.0a
request using a keyed message digest. Note that line breaks are
inserted for readability.
S: * OK [CAPABILITY IMAP4rev1 AUTH=OAUTH10A-PLUS SASL-IR]
IMAP4rev1 Server Ready
C: t1 AUTHENTICATE OAUTH10A-PLUS cD10bHMtdW5pcXVlLGE9dXNlckBleGFtcGxlL
mNvbQFob3N0PXNlcnZlci5leGFtcGxlLmNvbQFwb3J0PTE0MwFhdXRoPU9BdXRoI
HJlYWxtPSJFeGFtcGxlIixvYXV0aF9jb25zdW1lcl9rZXk9IjlkamRqODJoNDhka
nM5ZDIiLG9hdXRoX3Rva2VuPSJra2s5ZDdkaDNrMzlzanY3IixvYXV0aF9zaWduY
XR1cmVfbWV0aG9kPSJITUFDLVNIQTEiLG9hdXRoX3RpbWVzdGFtcD0iMTM3MTMxM
jAxIixvYXV0aF9ub25jZT0iN2Q4ZjNlNGEiLG9hdXRoX3NpZ25hdHVyZT0iU1Nkd
ElHRWdiR2wwZEd4bElIUmxZU0J3YjNRdSIBcXM9Y2JkYXRhPXRscy11bmlxdWU6U
0c5M0lHSnBaeUJwY3lCaElGUk1VeUJtYVc1aGJDQnRaWE56WVdkbFB3bz0BAQ==
S: t1 OK SASL authentication succeeded
As required by IMAP [RFC3501], the payloads are base64-encoded. The
decoded initial client response (with %x01 represented as ^A and
lines wrapped for readability) is:
p=tls-unique,a=user@example.com^A
host=server.example.com^A
port=143^A
auth=OAuth realm="Example",
oauth_consumer_key="9djdj82h48djs9d2",
oauth_token="kkk9d7dh3k39sjv7",
oauth_signature_method="HMAC-SHA1",
oauth_timestamp="137131201",
oauth_nonce="7d8f3e4a",
oauth_signature="SSdtIGEgbGl0dGxlIHRlYSBwb3Qu"^A
qs=cbdata=tls-unique:SG93IGJpZyBpcyBhIFRMUyBmaW5hbCBtZXNzYWdlPwo=^A^A
In this example the signature base string with line breaks added for
readability would be:
POST&http%3A%2F%2Fserver.example.com:143%2F&cbdata=tls-unique:SG93I
GJpZyBpcyBhIFRMUyBmaW5hbCBtZXNzYWdlPwo=%26oauth_consumer_key%3D9djd
j82h48djs9d2%26oauth_nonce%3D7d8f3e4a%26oauth_signature_method%3DHM
AC-SHA1%26oauth_timestamp%3D137131201%26oauth_token%3Dkkk9d7dh3k39s
jv7
4.3. 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 the needed Authorization header, which is how a client can query for the needed
scope. Note that line breaks are inserted for readability. scope. Note that line breaks are inserted for readability.
S: * CAPABILITY IMAP4rev1 AUTH=OAUTHBEARER SASL-IR IMAP4rev1 Server S: * CAPABILITY IMAP4rev1 AUTH=OAUTHBEARER SASL-IR IMAP4rev1 Server
Ready Ready
S: t0 OK Completed S: t0 OK Completed
C: t1 AUTHENTICATE OAUTHBEARER cD10bHMtdW5pcXVlLGE9dXNlckBleGFtcG C: t1 AUTHENTICATE OAUTHBEARER cD10bHMtdW5pcXVlLGE9dXNlckBleGFtcG
xlLmNvbQFob3N0PXNlcnZlci5leGFtcGxlLmNvbQFwb3J0PTE0MwFhdXRoP xlLmNvbQFob3N0PXNlcnZlci5leGFtcGxlLmNvbQFwb3J0PTE0MwFhdXRoP
skipping to change at page 14, line 12 skipping to change at page 12, line 29
The decoded server error response is: The decoded server error response is:
{ {
"status":"401", "status":"401",
"scope":"example_scope" "scope":"example_scope"
} }
The client responds with the required dummy response. The client responds with the required dummy response.
4.4. Failed Channel Binding 4.3. SMTP Example of a Failed Negotiation
This example shows a channel binding failure in an empty request.
The channel binding information is empty. Note that line breaks are
inserted for readability.
S: * CAPABILITY IMAP4rev1 AUTH=OAUTH10A-PLUS SASL-IR IMAP4rev1 Server
Ready
S: t0 OK Completed
C: t1 AUTHENTICATE OAUTH10A-PLUS cCxhPXVzZXJAZXhhbXBsZS5jb20BaG9z
dD1zZXJ2ZXIuZXhhbXBsZS5jb20BcG9ydD0xNDMBYXV0aD0BY2JkYXRhPQEB
S: + ewoic3RhdHVzIjoiNDEyIiwKInNjb3BlIjoiZXhhbXBsZV9zY29wZSIKfQ==
C: + AQ==
S: t1 NO SASL authentication failed
The decoded initial client response is:
p=tls-unique,a=user@example.com,^Ahost=server.example.com^A
port=143^Aauth=^Acbdata=^A^A
The decoded server response is:
{
"status":"412",
"scope":"example_scope"
}
The client responds with the required dummy response.
4.5. 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.
Note that line breaks are inserted for readability, and that the SMTP Note that line breaks are inserted for readability, and that the SMTP
protocol terminates lines with CR and LF characters (ASCII values protocol terminates lines with CR and LF characters (ASCII values
0x0D and 0x0A), these are not displayed explicitly in the example. 0x0D and 0x0A), these are not displayed explicitly in the example.
[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
C: AUTH OAUTHBEARER bixhPT1zb21ldXNlckBleGFtcGxlLmNvbQFhdXRoPUJlYXJlciB2 C: AUTH OAUTHBEARER bixhPT1zb21ldXNlckBleGFtcGxlLmNvbQFhdXRoPUJlYXJlciB2
RjlkZnQ0cW1UYzJOdmIzUmxja0JoZEhSaGRtbHpkR0V1WTI5dENnPT0BAQ== RjlkZnQ0cW1UYzJOdmIzUmxja0JoZEhSaGRtbHpkR0V1WTI5dENnPT0BAQ==
S: 334 eyJzdGF0dXMiOiI0MDEiLCJzY2hlbWVzIjoiYmVhcmVyIG1hYyIsInNjb3BlIjoia S: 334 eyJzdGF0dXMiOiI0MDEiLCJzY2hlbWVzIjoiYmVhcmVyIG1hYyIsInNjb3BlIjoia
HR0cHM6Ly9tYWlsLmdvb2dsZS5jb20vIn0K HR0cHM6Ly9tYWlsLmdvb2dsZS5jb20vIn0K
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 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.
5. Security Considerations 5. Security Considerations
OAuth 1.0a and OAuth 2 allows for a variety of deployment scenarios, OAuth 1.0a and OAuth 2 allows 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
skipping to change at page 16, line 4 skipping to change at page 13, line 33
OAUTHBEARER: This mechanism borrows from OAuth 2.0 bearer tokens OAUTHBEARER: This mechanism borrows from OAuth 2.0 bearer tokens
[RFC6750]. It relies on the application using TLS to protect the [RFC6750]. It relies on the application using TLS to protect the
OAuth 2.0 Bearer Token exchange; without TLS usage at the OAuth 2.0 Bearer Token exchange; without TLS usage at the
application layer this method is completely insecure. application layer this method is completely insecure.
Consequently, TLS MUST be provided by the application when Consequently, TLS MUST be provided by the application when
choosing this authentication mechanism. choosing this authentication mechanism.
OAUTH10A: This mechanism re-uses OAuth 1.0a MAC tokens (using the OAUTH10A: This mechanism re-uses OAuth 1.0a MAC tokens (using the
HMAC-SHA1 keyed message digest), as described in Section 3.4.2 of HMAC-SHA1 keyed message digest), as described in Section 3.4.2 of
[RFC5849]. To compute the keyed message digest in the same way [RFC5849]. To compute the keyed message digest in the same way
was in RFC 5839 this specification conveys additional parameters was in RFC 5839 this specification conveys additional parameters
between the client and the server. This SASL mechanism only between the client and the server. This SASL mechanism only
supports client authentication. If server-side authentication is supports client authentication. If server-side authentication is
desireable then it must be provided by the application underneath desireable then it must be provided by the application underneath
the SASL layer. The use of TLS is strongly RECOMMENDED. the SASL layer. The use of TLS is strongly RECOMMENDED.
OAUTH10A-PLUS: This mechanism adds the channel binding [RFC5056]
capability to OAUTH10A for protection against man-in-the-middle
attacks. OAUTH10A-PLUS mandates the usage of Transport Layer
Security (TLS) at the application layer.
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). The resource server should ensure that protocols, e.g., XMPP). The resource server should ensure that
actions taken in the authenticated channel are appropriate to the actions taken in the authenticated channel are appropriate to the
strength of the presented credential. strength of the presented credential.
skipping to change at page 17, line 48 skipping to change at page 15, line 24
Security Considerations: See this document Security Considerations: See this document
Published Specification: See this document Published Specification: See this document
For further information: Contact the authors of this document. For further information: Contact the authors of this document.
Owner/Change controller: the IETF Owner/Change controller: the IETF
Note: None Note: None
The IANA is requested to register the following SASL profile:
SASL mechanism profile: OAUTH10A-PLUS
Security Considerations: See this document
Published Specification: See this document
For further information: Contact the authors of this document.
Owner/Change controller: the IETF
Note: None
8. References 8. References
8.1. Normative References 8.1. Normative References
[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.
[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.
skipping to change at page 18, line 45 skipping to change at page 16, line 8
[RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax [RFC5234] Crocker, D. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", STD 68, RFC 5234, January 2008. Specifications: ABNF", STD 68, RFC 5234, January 2008.
[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.
[RFC5849] Hammer-Lahav, E., "The OAuth 1.0 Protocol", RFC 5849, [RFC5849] Hammer-Lahav, E., "The OAuth 1.0 Protocol", RFC 5849,
April 2010. April 2010.
[RFC5929] Altman, J., Williams, N., and L. Zhu, "Channel Bindings
for TLS", RFC 5929, July 2010.
[RFC6749] Hardt, D., "The OAuth 2.0 Authorization Framework", RFC [RFC6749] Hardt, D., "The OAuth 2.0 Authorization Framework", RFC
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.
8.2. Informative References 8.2. Informative References
[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-12 (work in (JWT)", draft-ietf-oauth-json-web-token-13 (work in
progress), October 2013. progress), November 2013.
[I-D.ietf-oauth-v2-http-mac] [I-D.ietf-oauth-v2-http-mac]
Richer, J., Mills, W., Tschofenig, H., and P. Hunt, "OAuth Richer, J., Mills, W., Tschofenig, H., and P. Hunt, "OAuth
2.0 Message Authentication Code (MAC) Tokens", draft-ietf- 2.0 Message Authentication Code (MAC) Tokens", draft-ietf-
oauth-v2-http-mac-04 (work in progress), July 2013. oauth-v2-http-mac-04 (work in progress), July 2013.
[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.
[RFC5321] Klensin, J., "Simple Mail Transfer Protocol", RFC 5321, [RFC5321] Klensin, J., "Simple Mail Transfer Protocol", RFC 5321,
skipping to change at page 19, line 47 skipping to change at page 17, line 4
Lodderstadt, Ryan Troll, Alexey Melnikov, Jeffrey Hutzelman, and Nico Lodderstadt, Ryan Troll, Alexey Melnikov, Jeffrey Hutzelman, and Nico
Williams. Williams.
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
directors was Stephen Farrell. directors 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 ]]
-12 -12
o Removed GSS-API components from the specification. o Removed -PLUS components from the specification.
-11 -11
o Removed GSS-API components from the specification.
o Updated security consideration section. o Updated security consideration section.
-10 -10
o Clarifications throughout the document in response to the feedback o Clarifications throughout the document in response to the feedback
from Jeffrey Hutzelman. from Jeffrey Hutzelman.
-09 -09
o Incorporated review by Alexey and Hannes. o Incorporated review by Alexey and Hannes.
skipping to change at page 20, line 31 skipping to change at page 17, line 39
-08 -08
o Fixed the channel binding examples for p=$cbtype o Fixed the channel binding examples for p=$cbtype
o More tuning of the authcid language and edited and renamed 3.2.1. o More tuning of the authcid language and edited and renamed 3.2.1.
-07 -07
o Struck the MUST langiage from authzid. o Struck the MUST langiage from authzid.
o
-06 -06
o Removed the user field. Fixed the examples again. o Removed the user field. Fixed the examples again.
o Added canonicalization language. o Added canonicalization language.
o
-05 -05
o Fixed the GS2 header language again. o Fixed the GS2 header language again.
o Separated out different OAuth schemes into different SASL o Separated out different OAuth schemes into different SASL
mechanisms. Took out the scheme in the error return. Tuned up mechanisms. Took out the scheme in the error return. Tuned up
the IANA registrations. the IANA registrations.
o Added the user field back into the SASL message. o Added the user field back into the SASL message.
o Fixed the examples (again). o Fixed the examples (again).
o
-04 -04
o Changed user field to be carried in the gs2-header, and made gs2 o Changed user field to be carried in the gs2-header, and made gs2
header explicit in all cases. header explicit in all cases.
o Converted MAC examples to OAuth 1.0a. Moved MAC to an informative o Converted MAC examples to OAuth 1.0a. Moved MAC to an informative
reference. reference.
o Changed to sending an empty client response (single control-A) as o Changed to sending an empty client response (single control-A) as
the second message of a failed sequence. the second message of a failed sequence.
o Fixed channel binding prose to refer to the normative specs and o Fixed channel binding prose to refer to the normative specs and
skipping to change at page 22, line 10 skipping to change at page 19, line 17
o Renamed draft into proper IETF naming format now that it's o Renamed draft into proper IETF naming format now that it's
adopted. adopted.
o Minor fixes. o Minor fixes.
Authors' Addresses Authors' Addresses
William Mills William Mills
Yahoo! Inc. Yahoo! Inc.
Email: wmills@yahoo-inc.com Email: wmills_92105@yahoo.com
Tim Showalter Tim Showalter
Email: tjs@psaux.com Email: tjs@psaux.com
Hannes Tschofenig Hannes Tschofenig
Nokia Solutions and Networks Nokia Solutions and Networks
Linnoitustie 6 Linnoitustie 6
Espoo 02600 Espoo 02600
Finland Finland
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