Network Working Group P. Hunt, Ed.
Internet-Draft Oracle
Intended status: Standards Track W. Denniss
Expires: April 2, 2017 Google
M. Ansari
Cisco
M. Jones
Microsoft
September 29, 2016
Security Event Token (SET)
draft-hunt-idevent-token-06
Abstract
This specification defines the Security Event token, which may be
distributed via a protocol such as HTTP. The Security Event Token
(SET) specification profiles the JSON Web Token (JWT) and may be
optionally signed and/or encrypted. A SET describes a statement of
fact that may be shared by an event publisher with event subscribers.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on April 2, 2017.
Copyright Notice
Copyright (c) 2016 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
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carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Table of Contents
1. Introduction and Overview . . . . . . . . . . . . . . . . . . 2
1.1. Notational Conventions . . . . . . . . . . . . . . . . . 4
1.2. Definitions . . . . . . . . . . . . . . . . . . . . . . . 4
2. The Security Event Token (SET) . . . . . . . . . . . . . . . 5
2.1. Core SET Claims . . . . . . . . . . . . . . . . . . . . . 8
2.2. Security Event Token Construction . . . . . . . . . . . . 10
3. Security Considerations . . . . . . . . . . . . . . . . . . . 13
3.1. Confidentiality and Integrity . . . . . . . . . . . . . . 13
3.2. Delivery . . . . . . . . . . . . . . . . . . . . . . . . 13
3.3. Sequencing . . . . . . . . . . . . . . . . . . . . . . . 13
3.4. Timing Issues . . . . . . . . . . . . . . . . . . . . . . 14
3.5. Distinguishing SETs from Access Tokens . . . . . . . . . 14
4. Privacy Considerations . . . . . . . . . . . . . . . . . . . 15
5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15
5.1. JSON Web Token Claims Registration . . . . . . . . . . . 15
5.1.1. Registry Contents . . . . . . . . . . . . . . . . . . 15
6. References . . . . . . . . . . . . . . . . . . . . . . . . . 15
6.1. Normative References . . . . . . . . . . . . . . . . . . 16
6.2. Informative References . . . . . . . . . . . . . . . . . 17
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 17
Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 17
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 18
1. Introduction and Overview
This specification defines an extensible Security Event Token (SET)
format which may be exchanged using protocols such as HTTP. The
specification builds on the JSON Web Token (JWT) format [RFC7519] in
order to provide a self-contained token that can be optionally signed
using JSON Web Signature (JWS) [RFC7515] and/or encrypted using JSON
Web Encryption (JWE) [RFC7516].
For the purpose of this specification, an event is a statement of
fact by a publisher (also known as the event issuer) that the state
of a security subject (e.g., a web resource, token, IP address) it
controls or is aware of, has changed in some way (explicitly or
implicitly). A security subject may be permanent (e.g., a user
account) or temporary (e.g., a login session) in nature. A state
change may include direct changes of entity state, implicit changes
to state or other higher-level security statements such as:
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o The creation, modification, removal of a resource.
o The resetting or suspension of an account.
o The revocation of a security token prior to its expiry.
o The logout of a user session. Or,
o A cumulative conclusion such as to indicate that a user has taken
over an email identifier that may have been used in the past by
another user.
Based on some agreed upon criteria for an event Feed, the publisher
distributes events to the appropriate subscribers. While an event
may be delivered via synchronous means (e.g., HTTP POST), the
distribution of the event often happens asynchronously to the change
of state which generated the security event. As an example, an
OAuth2 Authorization Server [RFC6749], having received a token
revocation request [RFC7009], may issue a token revocation event to
downstream web resource providers. Having been informed of a token
revocation, the OAuth2 web resource service provider may add the
token identifier to its local revocation list assuming the token has
not already expired.
A subscriber having received an event, validates and interprets the
event and takes its own independent action, if any. For example,
having been informed of a personal identifier now being associated
with a different security subject (i.e., is being used by someone
else), the subscriber may choose to ensure that the new user is not
granted access to resources associated with the previous user. Or it
may not have any relationship with the subject, and no action is
taken.
While subscribers will often take actions upon receiving one or more
events, events MUST NOT be assumed to be commands or requests. To do
so requires complex bi-directional signals and error recovery
mechanisms that fall outside the scope of this specification. The
intent of this specification is to define a way of exchanging
statements of fact that subscribers may interpret for their own
purposes. Since events are typically historical statements by a
publisher and are not commands, idempotency or lack thereof, does not
apply.
Unless otherwise specified, this specification uses example events
intended as non-normative examples showing how an event may be used.
It is expected that other specifications will use this specification
to define normative events.
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This specification is scoped to security and identity related events.
While event tokens may be used for other purposes, the specification
only considers security and privacy concerns relevant to identity and
personal information.
1.1. Notational Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. These
keywords are capitalized when used to unambiguously specify
requirements of the protocol or application features and behavior
that affect the inter-operability and security of implementations.
When these words are not capitalized, they are meant in their
natural-language sense.
For purposes of readability, examples are not URL encoded.
Implementers MUST percent encode URLs as described in Section 2.1 of
[RFC3986].
Throughout this document, all figures MAY contain spaces and extra
line-wrapping for readability and space limitations. Similarly, some
URIs contained within examples have been shortened for space and
readability reasons.
1.2. Definitions
The following definitions are used with SETs:
Feed Publisher
The Feed Publisher creates SETs to be distributed to registered
subscribers. In JWT terminology, the Feed Publisher is also known
as the issuer ("iss").
Security Event Token (SET)
An SET is a JWT that is to be distributed to one or more
registered subscribers. A SET MAY be signed or encrypted using
JWS and/or JWE for authentication and confidentiality reasons.
Feed
A Feed is a logical grouping of SETs or a context under which SETs
may be issued. A Subscriber registers with the Feed Publisher to
subscribe to SETs associated with a Feed. How a Feed is defined
or the method for subscription is out-of-scope of this
specification.
Subscriber
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A Subscriber registers to receive SETs from a Feed Publisher using
a protocol such as HTTP. The method of registration and delivery
is out-of-scope of this specification.
Security Subject
A Security Subject is the entity to which a SET refers. A
Security Subject may be a principle (e.g., Section 4.1.2
[RFC7519]), a web resource, or other thing such as an IP address
that a SET might reference.
2. The Security Event Token (SET)
A SET conveys a statement (in the form of a JWT [RFC7519]) about a
single security event in relation to a Security Subject that may be
of interest to a Subscriber or set of Subscribers receiving SETs from
a Feed Publisher.
The schema and structure of a SET follows the JWT [RFC7519]
specification. A SET has the following structure:
o An outer JSON structure that acts as the SET envelope. The
envelope contains a set of JSON attributes, called JWT claims,
typically common to every SET or common to a number of different
Security Events within a single profiling specification or a
related series of specifications. Claims in the envelope SHOULD
be registered in the JWT Token Claims Registry Section 10.1
[RFC7519] or be Public Claims or Private Claims as also defined in
[RFC7519].
o Envelope claims that are profiled and defined in this
specification are used to validate the SET and determine the event
data included. The claim "events" describes the type of SET event
and indicates the data that MAY be present in the SET. While a
SET contains a single event, it MAY have multiple extensions
providing additional data about the same event. The primary event
is the first value in the "events" array, while event extensions
are the 2nd, 3rd, etc.
o For each value of "events", a JSON attribute, whose value is a
JSON object, MAY be added known as an event "payload". The
payload object contains claims typically unique to the events URI
value and are not registered as JWT claims. These claims are
defined within their associated event specification. Event
extensions can be used for many purposes. Some examples include
but are not limited to:
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* A categorization extension applied to multiple event types in
order to provide classification information (e.g. threat type
or level).
* Enhancement of an existing specifications the arise over time.
* Correlation extensions needed to link a potential series of
events.
* Localized contextual extensions needed between a publisher and
subscriber.
The following is a non-normative example showing a hypothetical SCIM
password reset SET. The example also shows an example where the
issuer has provided an extension ("https://example.com/scim/event/
passwordResetExt") that is used to convey additional information such
as the current count of reset attempts:
{
"jti": "3d0c3cf797584bd193bd0fb1bd4e7d30",
"events":[
"urn:ietf:params:scim:event:passwordReset",
"https://example.com/scim/event/passwordResetExt"
],
"iat": 1458496025,
"iss": "https://scim.example.com",
"aud":[
"https://jhub.example.com/Feeds/98d52461fa5bbc879593b7754",
"https://jhub.example.com/Feeds/5d7604516b1d08641d7676ee7"
],
"sub":"https://scim.example.com/Users/44f6142df96bd6ab61e7521d9",
"urn:ietf:params:scim:event:passwordReset":{
"id":"44f6142df96bd6ab61e7521d9"
},
"https://example.com/scim/event/passwordResetExt":{
"resetAttempts":5
}
}
Figure 1: Example SCIM Password Reset Event
The event in the figure above expresses hypothetical password reset
event for SCIM [RFC7644]. The JWT consists of:
o An "events" claim specifying the hypothetical SCIM urn
("urn:ietf:params:scim:event:passwordReset") for a password reset,
and a custom extension, "https://example.com/scim/event/
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passwordResetExt", that is used to provide additional event
information such as the current count of resets.
o An "iss" claims, denotes the event publisher.
o The "sub" claims specifies the SCIM resource URI that was
affected.
o The "aud" claims specifies the intended audience for the event.
In practical terms, this MAY be the URI for the event Feed that a
client has subscribed to.
Additional extensions to an event may be added by adding more values
to the "events" claims. For each event URI value specified, there
MAY be a corresponding claim that has a JSON object that contains the
claims associated with that event (e.g.,
"https://example.com/scim/event/passwordResetExt"). In this example,
the SCIM event indicates that a password has been updated and the
current password reset count is 5. Notice that the value for
"resetAttempts" is actually part of its own JSON object
"https://example.com/scim/event/passwordResetExt".
Here is another example event token, this one for a Logout Token:
{
"iss": "https://server.example.com",
"aud": "https://rp.example.com",
"jti": "3d0c3cf797584bd193bd0fb1bd4e7d30",
"iat": 1458668180,
"exp": 1458668580,
"sub": "248289761001",
"events": [
"https://specs.openid.net/logout"
],
"https://specs.openid.net/logout": {
"iss": "https://token.example.com",
"sid": "08a5019c-17e1-4977-8f42-65a12843ea02"
}
}
Figure 2: Example OpenID Logout Event
In the above example, the event has its own issuer,
"https://server.example.com" while the event is about the logging out
of a user session identified in the event extension by "jti" that was
issued by "https://token.example.com".
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In the following example, a fictional medical service collects
consent for medical actions and notifies other parties. The
individual for whom consent is identified was originally
authenticated via OpenID Connect. In this case, the issuer of the
SET event is an application rather than the OpenID provider:
{
"jti": "fb4e75b5411e4e19b6c0fe87950f7749",
"events":[
"https://openid.net/heart/consent.html"
],
"sub": "248289761001",
"iat": 1458496025,
"iss": "https://my.examplemed.com",
"aud":[
"https://rp.example.com"
],
"https://openid.net/heart/consent":{
"consentUri":[
"https://terms.examplemed.com/labdisclosure.html#Agree"
]
}
}
Figure 3: Example Consent Event
In the above example "iss" and "sub" contained within the claim
"https://openid.net/heart/consent", refer to the subject and issuer
of the original OpendID Provider. They are distinct from the top
level value of "iss" which always refers to the issuer of the event -
a medical consent service that is a relying party to the OpenID
Provider.
2.1. Core SET Claims
The following are claims that are based on [RFC7519] claim
definitions and are profiled for use in an event token:
jti
As defined by Section 4.1.7 [RFC7519] contains a unique identifier
for an event. The identifier SHOULD be unique within a particular
event Feed and MAY be used by clients to track whether a
particular event has already been received. This claim is
REQUIRED.
iss
A single valued String containing the URI of the service provider
publishing the SET (the issuer). This claim is REQUIRED.
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aud
A multi-valued String containing the URIs representing the
audience of the event. Values are typically URLs of the Feeds the
event is associated with. When an event has multiple audiences
that go to the same subscriber, the publisher is not obligated to
deliver repeated events to the same subscriber. This claim is
RECOMMENDED.
iat
As defined by Section 4.1.6 [RFC7519], a value containing a
NumericDate, which represents when the event was issued. Unless
otherwise specified, the value SHOULD be interpreted by the
subscriber as equivalent to the actual time of the event. This
claim is REQUIRED.
nbf
As defined by Section 4.1.5 [RFC7519], a value containing a
NumericDate, which represents a future date when the event will
occur. This claim is OPTIONAL.
sub As defined by Section 4.1.2 [RFC7519], a String or URI value
representing the principal or the subject of the SET. This is
usually the entity whose "state" was changed. For example, an IP
Address was added to a black list. A URI representing a user
resource that was modified. A token identifier for a revoked
token. If used, the profile specification SHOULD define the
content and format semantics for the value. This claim is
OPTIONAL, as the principal for any given profile may already be
identified without the inclusion of a subject claim.
exp As defined by [RFC7519], this claim is time on which the JWT
MUST NOT be accepted for processing. In the context of a SET
however, this notion does not apply since a SET reflects something
that has already been processed and is historical in nature.
While some specifications MAY have a need for this claim, its use
in general cases is NOT RECOMMENDED.
The following are new claims defined by this specification:
events
A multi-valued String that contains one or more URIs representing
the type of event being expressed and the claims that MAY be
available within the JWT. The first value SHALL indicate the type
of SET event and following values represent extensions to that
event. For each value present, there MAY be an associated JSON
sub-objects present in the SET. Each JSON sub-object is denoted
by a claim whose name matches a value in "events". This claim is
REQUIRED to have at least one value.
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txn
An OPTIONAL single-valued String value that represents a unique
transaction identifier. In cases where multiple SETs are issued
based on different event URIs, the transaction identifier MAY be
used to correlate SETs to the same originating event or stateful
change.
2.2. Security Event Token Construction
A SET is a JWT [RFC7519] that is constructed by building a JSON
structure that constitutes an event object and which is then used as
the body of a JWT.
While this specification uses JWT to convey a SET, implementers SHALL
NOT use SETs to convey authentication or authorization assertions.
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The following is an example event token (which has been formatted for
readability):
{
"jti": "4d3559ec67504aaba65d40b0363faad8",
"iat": 1458496404,
"iss": "https://scim.example.com",
"aud":[
"https://scim.example.com/Feeds/98d52461fa5bbc879593b7754",
"https://scim.example.com/Feeds/5d7604516b1d08641d7676ee7"
],
"events":[
"urn:ietf:params:scim:event:create"
],
"urn:ietf:params:scim:event:create":{
"ref": "https://scim.example.com/Users/44f6142df96bd6ab61e7521d9",
"attributes":["id", "name", "userName", "password", "emails"],
"values":{
"emails":[
{"type":"work", "value":"jdoe@example.com"}
],
"password":"not4u2no",
"userName":"jdoe",
"id":"44f6142df96bd6ab61e7521d9",
"name":{
"givenName":"John",
"familyName":"Doe"
}
}
}
}
Figure 4: Example Event JSON Data
When transmitted, the above JSON body must be converted into a JWT as
per [RFC7519]. In this example, because the event contains attribute
values, the token MUST be encrypted per JWE (see [RFC7516]) before
transmission.
The following is an example of a SCIM Event expressed as an unsecured
JWT. The JWT header of:
{"alg":"none"}
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Base64url encoding of the octets of the UTF-8 representation of the
header yields:
eyJhbGciOiJub25lIn0
The example JSON Event Data is encoded as follows: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 encoded JWS signature is the empty string. Concatenating the
parts yields:
eyJhbGciOiJub25lIn0
.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.
Figure 5: Example Unsecured Event Token
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To create and or validate a signed or encrypted SET, follow the
instructions in section 7 of [RFC7519].
3. Security Considerations
3.1. Confidentiality and Integrity
SETs may often contain sensitive information. Therefore, methods for
distribution of events SHOULD require the use of a transport-layer
security mechanism when distributing events. Parties MUST support
TLS 1.2 [RFC5246] and MAY support additional transport-layer
mechanisms meeting its security requirements. When using TLS, the
client MUST perform a TLS/SSL server certificate check, per
[RFC6125]. Implementation security considerations for TLS can be
found in "Recommendations for Secure Use of TLS and DTLS" [RFC7525].
Security Events distributed through third-parties or that carry
personally identifiable information, SHOULD be encrypted using JWE
[RFC7516] or secured for confidentiality by other means.
Security Events distributed without authentication over the channel,
such as via TLS ([RFC5246] and [RFC6125]), and/or OAuth2 [RFC6749],
or Basic Authentication [RFC7617], MUST be signed using JWS [RFC7515]
so that individual events MAY be authenticated and validated by the
subscriber.
3.2. Delivery
This specification does not define a delivery mechanism by itself.
In addition to confidentiality and integrity (discussed above),
implementers and profile specifications MUST consider the
consequences of delivery mechanisms that are not secure and/or not
assured. For example, while a SET may be end-to-end secured using
JWE, that alone will not guarantee that the correct subscribing party
knows they should have received a particular SET.
3.3. Sequencing
As defined in this specification, there is no defined way to order
multiple SETs in a sequence. Depending on the type and nature of SET
event, order may or may not matter. For example, in provisioning,
event order is critical -- an object could not be modified before it
was created. In other SET types, such as a token revocation, the
order of SETs for revoked tokens does not matter. If however, the
event was described as a log-in or logged-out status for a user
subject, then order becomes important.
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Extension specifications and implementers SHOULD take caution when
using timestamps such as "iat" to define order. Distributed systems
will have some amount of clock-skew and thus time by itself will not
guarantee order.
Specifications profiling SET SHOULD define a mechanism for detecting
order or sequence of events. For example, the _txn_ claim could be
defined as an ordered value (e.g. a counter) that the publisher
defines.
3.4. Timing Issues
When SETs are delivered asynchronously and/or out-of-band with
respect to the original action that incurred the security event, it
is important to consider that a SET might be delivered to a
Subscriber in advance or well behind the process that caused the
event. For example, a user having been required to logout and then
log back in again, may cause a logout SET to be issued that may
arrive at the same time as the user-agent accesses a web site having
just logged-in. If timing is not handled properly, the effect would
be to erroneously treat the new user session as logged out.
Profiling specifications SHOULD be careful to anticipate timing and
subject selection information. For example, it might be more
appropriate to cancel a "session" rather than a "user".
Alternatively, the specification could use timestamps that allows new
sessions to be started immediately after a stated logout event time.
3.5. Distinguishing SETs from Access Tokens
Because [RFC7519] states that "all claims that are not understood by
implementations MUST be ignored.", there is a consideration that a
SET token might be confused as an access or authorization token in
the case where a SET is mistakenly or intentionally intercepted and
presented as an access token. To avoid this it is recommended that
implementers consider one or more of the following:
o Avoid use of the JWT claim "exp" within the envelope.
o Where possible, use a separate "aud" claim value to distinguish
between the SET subscriber and the audience of an access token.
For example, a Logout while intended for the same relying party
could use a different audience to distinguish between normal
access and logout notification.
o Modify access validation systems to check for the presence of the
"events" claim as a means to detect SET event tokens. This is
particularly useful if the same endpoint may receive both types of
tokens.
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o Consider avoiding use of the "sub" claim at the top level.
4. Privacy Considerations
If a SET needs to be retained for audit purposes, JWS MAY be used to
provide verification of its authenticity.
Event Publishers SHOULD attempt to specialize Feeds so that the
content is targeted to the specific business and protocol needs of
subscribers.
When sharing personally identifiable information or information that
is otherwise considered confidential to affected users, the
publishers and subscribers MUST have the appropriate legal agreements
and user consent in place.
The propagation of subject identifiers can be perceived as personally
identifiable information. Where possible, publishers and subscribers
should devise approaches that prevent propagation -- for example, the
passing of a hash value that requires the subscriber to already know
the subject.
5. IANA Considerations
5.1. JSON Web Token Claims Registration
This specification registers the "events" and the "txn" claims in the
IANA "JSON Web Token Claims" registry [IANA.JWT.Claims] established
by [RFC7519].
5.1.1. Registry Contents
o Claim Name: "events"
o Claim Description: Security Event URIs
o Change Controller: IESG
o Specification Document(s): Section 2 of [[ this specification ]]
o Claim Name: "txn"
o Claim Description: SET Transaction Identifier
o Change Controller: IESG
o Specification Document(s): Section 2 of [[ this specification ]]
6. References
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6.1. Normative References
[IANA.JWT.Claims]
IANA, "JSON Web Token Claims",
<http://www.iana.org/assignments/jwt>.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<http://www.rfc-editor.org/info/rfc2119>.
[RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
Resource Identifier (URI): Generic Syntax", STD 66,
RFC 3986, DOI 10.17487/RFC3986, January 2005,
<http://www.rfc-editor.org/info/rfc3986>.
[RFC5246] Dierks, T. and E. Rescorla, "The Transport Layer Security
(TLS) Protocol Version 1.2", RFC 5246,
DOI 10.17487/RFC5246, August 2008,
<http://www.rfc-editor.org/info/rfc5246>.
[RFC6125] Saint-Andre, P. and J. Hodges, "Representation and
Verification of Domain-Based Application Service Identity
within Internet Public Key Infrastructure Using X.509
(PKIX) Certificates in the Context of Transport Layer
Security (TLS)", RFC 6125, DOI 10.17487/RFC6125, March
2011, <http://www.rfc-editor.org/info/rfc6125>.
[RFC6749] Hardt, D., Ed., "The OAuth 2.0 Authorization Framework",
RFC 6749, DOI 10.17487/RFC6749, October 2012,
<http://www.rfc-editor.org/info/rfc6749>.
[RFC7159] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", RFC 7159, DOI 10.17487/RFC7159, March
2014, <http://www.rfc-editor.org/info/rfc7159>.
[RFC7519] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token
(JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015,
<http://www.rfc-editor.org/info/rfc7519>.
[RFC7525] Sheffer, Y., Holz, R., and P. Saint-Andre,
"Recommendations for Secure Use of Transport Layer
Security (TLS) and Datagram Transport Layer Security
(DTLS)", BCP 195, RFC 7525, DOI 10.17487/RFC7525, May
2015, <http://www.rfc-editor.org/info/rfc7525>.
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[RFC7617] Reschke, J., "The 'Basic' HTTP Authentication Scheme",
RFC 7617, DOI 10.17487/RFC7617, September 2015,
<http://www.rfc-editor.org/info/rfc7617>.
6.2. Informative References
[idevent-scim]
Oracle Corporation, "SCIM Event Extensions (work in
progress)", <draft-hunt-idevent-scim-00.txt>.
[RFC7009] Lodderstedt, T., Ed., Dronia, S., and M. Scurtescu, "OAuth
2.0 Token Revocation", RFC 7009, DOI 10.17487/RFC7009,
August 2013, <http://www.rfc-editor.org/info/rfc7009>.
[RFC7515] Jones, M., Bradley, J., and N. Sakimura, "JSON Web
Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, May
2015, <http://www.rfc-editor.org/info/rfc7515>.
[RFC7516] Jones, M. and J. Hildebrand, "JSON Web Encryption (JWE)",
RFC 7516, DOI 10.17487/RFC7516, May 2015,
<http://www.rfc-editor.org/info/rfc7516>.
[RFC7517] Jones, M., "JSON Web Key (JWK)", RFC 7517,
DOI 10.17487/RFC7517, May 2015,
<http://www.rfc-editor.org/info/rfc7517>.
[RFC7644] Hunt, P., Ed., Grizzle, K., Ansari, M., Wahlstroem, E.,
and C. Mortimore, "System for Cross-domain Identity
Management: Protocol", RFC 7644, DOI 10.17487/RFC7644,
September 2015, <http://www.rfc-editor.org/info/rfc7644>.
Appendix A. Acknowledgments
The editors would like to thank the participants in the IETF id-event
mailing list and related working groups for their support of this
specification.
Appendix B. Change Log
Draft 01 - PH - Renamed eventUris to events
Draft 00 - PH - First Draft
Draft 01 - PH - Fixed some alignment issues with JWT. Remove event
type attribute.
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Draft 02 - PH - Renamed to Security Events, Removed questions,
clarified examples and intro text, and added security and privacy
section.
Draft 03 - PH
General edit corrections from Sarah Squire
Changed "event" term to "SET"
Corrected author organization for William Denniss to Google
Changed definition of SET to be 2 parts, an envelope and 1 or more
payloads.
Clarified that the intent is to express a single event with
optional extensions only.
- mbj - Registered "events" claim, and proof-reading corrections.
Draft 04 - PH -
o Re-added the "sub" claim with clarifications that any SET type may
use it.
o Added additional clarification on the use of envelope vs. payload
attributes
o Added security consideration for event timing.
o Switched use of "attribute" to "claim" for consistency.
o Revised examples to put "sub" claim back in the top level.
o Added clarification that SETs typically do not use "exp".
o Added security consideration for distinguishing Access Tokens and
SETs.
Draft 05 - PH - Fixed find/replace error that resulted in claim being
spelled claimc
Draft 06 - PH -
o Corrected typos
o New txn claim
o New security considerations Sequencing and Timing Issues
Authors' Addresses
Phil Hunt (editor)
Oracle Corporation
Email: phil.hunt@yahoo.com
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William Denniss
Google
Email: wdenniss@google.com
Morteza Ansari
Cisco
Email: morteza.ansari@cisco.com
Michael B. Jones
Microsoft
Email: mbj@microsoft.com
URI: http://self-issued.info/
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