Internet DRAFT - draft-hunt-secevent-distribution
draft-hunt-secevent-distribution
Network Working Group P. Hunt, Ed.
Internet-Draft Oracle
Intended status: Standards Track M. Scurtescu
Expires: September 9, 2017 Google
March 8, 2017
SET Token Delivery Using HTTP
draft-hunt-secevent-distribution-01
Abstract
This specification defines how a series of security event tokens
(SETs) may be delivered to a previously registered receiver using
HTTP over TLS. The specification defines the metadata the an Event
Transmitter uses to describe the Event Receiver's HTTP endpoint and
the SET token delivery configuration. The specification defines how
the Event Receiver may check the current configuration metadata and
delivery status using HTTP GET over TLS. The specification also
defines how delivery can be assured subject to the SET Token
Receiver's need for assurance.
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
working documents as Internet-Drafts. The list of current Internet-
Drafts is at http://datatracker.ietf.org/drafts/current/.
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 September 9, 2017.
Copyright Notice
Copyright (c) 2017 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. Control Plane - Monitoring . . . . . . . . . . . . . . . . . 6
2.1. Event Stream Configuration . . . . . . . . . . . . . . . 6
2.2. Event Stream State Model . . . . . . . . . . . . . . . . 9
2.3. Checking Stream Configuration and Stream State . . . . . 11
3. Data Plane . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.1. Event Delivery Process . . . . . . . . . . . . . . . . . 13
3.2. Event Stream State . . . . . . . . . . . . . . . . . . . 14
3.3. HTTP POST Delivery . . . . . . . . . . . . . . . . . . . 15
3.4. Event Stream Verification . . . . . . . . . . . . . . . . 18
4. Control Plane - Management and Provisioning . . . . . . . . . 20
4.1. Event Stream Resource Type Definition . . . . . . . . . . 20
4.2. Creating A New Event Stream . . . . . . . . . . . . . . . 22
4.3. Updating An Event Stream . . . . . . . . . . . . . . . . 24
5. Security Considerations . . . . . . . . . . . . . . . . . . . 25
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 25
6.1. SCIM Schema Registration . . . . . . . . . . . . . . . . 26
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 26
7.1. Normative References . . . . . . . . . . . . . . . . . . 26
7.2. Informative References . . . . . . . . . . . . . . . . . 27
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 27
Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 28
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 28
1. Introduction and Overview
This specification defines how a stream of SETs (see
[I-D.ietf-secevent-token]) can be transmitted to a previously
registered Event Receiver using HTTP POST [RFC7231] over TLS. The
specification defines the metadata the Event Transmitter uses to
describe the Event Receiver's HTTP endpoint and the SET token
delivery configuration. The specification defines how the Event
Receiver may check the current configuration metadata and delivery
status using HTTP GET over TLS. The specification also defines how
delivery can be assured subject to the SET Token Receiver's need for
assurance.
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The following diagram shows a typical SET Event Stream. A stream
consists of a pair of HTTP endpoints, one for the event stream
transmitter and one for the receiver. The receiver endpoint is used
by the transmitter to deliver SET events via HTTPS POST and is known
as the "Data Plane". The transmitter's HTTP endpoint is used by the
receiver to perform HTTPS GET requests to check the stream status and
is known as the "Control Plane". In the diagram, the arrow heads
point to the service provider (the direction of an HTTP request):
+-----------+ Data Plane +----------+
|Transmitter+------HTTP POST--------> Receiver |
| <------HTTP GET---------+ |
+-----------+ Control Plane +----------+
Figure 1: SET Event Stream
In some service provider relationships, for example between Identity
Providers and Relying Parties, there may be a need to have bi-
directional SET event exchange. This involves establishing a second
event stream that works with transmitter and receiver roles reversed.
Identity Relying
Provider Party
IDP to RP Stream
+-----------+ Data Plane +------------+
|Transmitter+-----------------------> Receiver |
| <-----------------------+ |
+-----------+ Control Plane +------------+
RP to IDP Stream
+-----------+ Data Plane +------------+
| Receiver <-----------------------+ Transmitter|
| +-----------------------> |
+-----------+ Control Plane +------------+
Figure 2: Duplexed Streams
This specification contains two major sections:
Control Plane The service through which Event Receivers can review
and optionally managed Event Streams. It defines the metadata
associated with Event Streams along with stream status reporting.
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Data Plane Through which SET Events are delivered by an Event
Transmitter to an Event Receiver using a defined Event Stream.
The Data Plane includes a verification process which tests and
validates Event Stream configuration. The Data plan defines
processing and error signaling used in the delivery of SETs.
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 documents all figures MAY contain spaces and extra
line-wrapping for readability and space limitations. Similarly, some
URI's contained within examples, have been shortened for space and
readability reasons.
1.2. Definitions
This specification assumes terminology defined in the Security Event
Token specification[I-D.ietf-secevent-token] .
The following definitions are defined for Security Event
distribution:
Identity Provider
An Identity Provider is a service provider that issues
authentication assertions that may be used by Relying Party
service providers to establish login sessions with users.
Examples of Identity Providers are defined in: OpenID Connect
[openid-connect-core] and SAML2 [saml-core-2.0]. For the purpose
of this specification an Identity Provider also includes any
provider of services where the compromise of an account may open
up relying parties to attack. For example for the purposes of
security events, an email service provider could be considered an
"implicit" Identity Provider.
Relying Party
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A Relying Party is a service provider that accepts assertions from
Identity Providers to establish sessions. Examples of Relying
Parties are defined in: OpenID Connect [openid-connect-core] and
SAML2 [saml-core-2.0]
Event Transmitter
A service provider that delivers SETs to other providers known as
Event Receivers. Some examples of Event Transmitters are Identity
Providers and Relying Parties. An Event Transmitter is
responsible for offering a service that allows the Event Receiver
to check the Event Stream configuration and status known as the
"Control Plane".
Event Receiver
A service provider that registers to receive SETs from an Event
Transmitter and provides an endpoint to receive SETs via HTTP POST
(known as the "Data Plane"). Some examples of Event Receivers are
Identity Providers and Relying Parties. Event Receivers can check
current Event Stream configuration and status by accessing the
Event Transmitters "Control Plane".
Event Stream
An Event Stream establishes Event Receiver communication
endpoints, security configuration and feed content that is used by
an Event Transmitter to send a series of SET Events to an Event
Receiver. An Event Stream defines a "Data Plane" and "Control
Plane" service relationship between an Event Transmitter and and
Event Receiver.
Control Plane
A Control Plane represents an service offered by an Event
Transmitter that lets an Event Receiver query the current
operational and/or error status of an Event Stream. The Control
Plane MAY also be used to retrieve Event Stream and SET
configuration data.
Data Plane
The Data Plane represents the HTTP service offered by an Event
Receiver that allows the Event Transmitter to deliver multiple
SETs via HTTP POST as part of an Event Stream.
Event Family
An Event Family is a URI that describes the set of events types be
issued in an Event Stream.
Subject
The security subject around which a security event has occurred.
For example, a security subject might per a user, a person, an
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email address, a service provider entity, an IP address, an OAuth
Client, a mobile device, or any identifiable thing referenced in
security and authorization systems.
2. Control Plane - Monitoring
The Control Plane is provided by the Event Transmitter and enables
Event Receivers to check the Event Stream configuration and check for
transmission errors. This section describes mandatory to implement
functionality to enable Event Receivers to detect SET delivery
problems that may occur when an Event Transmitter fails to deliver
SETs.
Implementers MAY optionally implement and support full Event Stream
provisioning and management as described in Section 4. This
functionality also allows Event Receivers to "pause", "disable", or
re-enable Event Streams in scenario where the operational needs of
the receiver need to be co-ordinated with Event Transmitters (see
Section 2.2 and Section 4.3).
SCIM defines flexible mechanisms to ease adaptability to different
underlying data systems while maximizing inter-operabilty. Section 2
[RFC7643] SHALL provide the processing rule that enable Control Plane
providers and clients negotiate specific attributes (metadata)
including differing provider definitions of attribute types,
mutability, cardinality, or returnability that MAY differ. For HTTP
method handling and error signaling, the processing rules in
[RFC7644] SHALL apply.
2.1. Event Stream Configuration
An Event Stream represents an agreement to deliver SETs from a
specified Feed URI from an Event Transmitter to an Event Receiver.
The method of delivery and the parameters for delivery are specified
a set of parameters called Event Stream metadata (see Section 2.1).
An Event Stream is defined by the following metadata:
feedUri
An OPTIONAL JSON String value containing the URI for a feed
supported by the feed provider. It describes the content of the
feed and MAY also be a resolvable URI where the feed meta data may
be returned as a JSON object. REQUIRED.
methodUri
A REQUIRED JSON String value which is a URI with a prefix of
"urn:ietf:params:set:method". This specification defines HTTP
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POST delivery method:
"urn:ietf:params:set:method:HTTP:webCallback"
in which the Feed Provider delivers events using HTTP POST to a
specified callback URI.
deliveryUri
A JSON String value containing a URI that describes the location
where SETs are received (e.g. via HTTP POST). Its format and
usage requirements are defined by the associated "methodUri".
aud
An OPTIONAL JSON Array of JSON String values which are URIs
representing the audience(s) of the Event Stream. The value SHALL
be the value of SET "aud" claim sent to the Event Receiver.
feedJwk
An OPTIONAL public JSON Web Key (see [RFC7517]) from the Event
Transmitter that will be used by the Event Receiver to verify the
authenticity of issued SETs.
confidentialJwk
An OPTIONAL public JSON Web Key (see [RFC7517]) for the Event
Receiver that MAY be used by the Feed Provider to encrypt SET
tokens for the specified Event Receiver.
subStatus
An OPTIONAL JSON String keyword that indicates the current state
of an Event Stream. More information on the Event Stream state
can be found in Section 2.2. Valid keywords are:
"on" - indicates the Event Stream has been verified and that
the Feed Provider MAY pass SETs to the Event Receiver.
"verify" - indicates the Event Stream is pending verification.
While in "verify", SETs, except for the verify SET (see
Section 3.4) are not delivered to the Event Receiver. Once
verified, the status returns to "on".
"paused" - indicates the Event Stream is temporarily suspended.
While "paused", SETs SHOULD be retained and delivered when
state returns to "on". If delivery is paused for an extended
period defined by the Event Transmitter, the Event Transmitter
MAY change the state to "off" indicating SETs are no longer
retained.
"off" - indicates that the Event Stream is no longer passing
SETs. While in off mode, the Event Stream metadata is
maintained, but new events are ignored, not delivered or
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retained. Before returning to "on", a verification MUST be
performed.
"fail" - indicates that the Event Stream was unable to deliver
SETs to the Event Receiver due an unrecoverable error or for an
extended period of time. Unlike paused status, a failed Event
Stream does not retain existing or new SETs that are issued.
Before returning to "on", a verification MUST be performed.
maxRetries
An OPTIONAL JSON number indicating the maximum number of attempts
to deliver a SET. A value of '0' indicates there is no maximum.
Upon reaching the maximum, the Event Stream "subStatus" attribute
is set to "failed".
maxDeliveryTime
An OPTIONAL number indicating the maximum amount of time in
seconds a SET MAY take for successful delivery per request or
cumulatively across multiple retries. Upon reaching the maximum,
the Event Stream "subStatus" is set to "failed". If undefined,
there is no maximum time.
minDeliveryInterval
An OPTIONAL JSON integer that represents the minimum interval in
seconds between deliveries. A value of '0' indicates delivery
should happen immediately. When delivery is a polling method
(e.g. HTTP GET), it is the expected time between Event Receiver
attempts. When in push mode (e.g. HTTP POST), it is the interval
the server will wait before sending a new event or events.
txErr
An OPTIONAL JSON String keyword value. When the Event Stream has
"subState" set to "fail", one of the following error keywords is
set:
"connection" indicates an error occurred attempting to open a
TCP connection with the assigned endpoint.
"tls" indicates an error occurred establishing a TLS connection
with the assigned endpoint.
"dnsname" indicates an error occurred establishing a TLS
connection where the dnsname was not validated.
"receiver" indicates an error occurred whereby the Event
Receiver has indicated an error for which the Event Transmitter
is unable to correct.
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[[Editors note: other conditions?]]
txErrDesc
An OPTIONAL String value that is usually human readable that
provides further diagnostic detail by the indicated "txErr" error
code.
Additional Event Stream metadata (attributes) MAY be defined as
extensions. The method for adding new attributes is defined in
Section 3.3 [RFC7643].
2.2. Event Stream State Model
The Event Stream configuration attribute "subStatus" tracks the state
of any particular Event Stream with regards to whether SETs are ready
or able to be delivered. The impact on delivery processing is
described in Table 1.
The following is the state machine representation of a Event Stream
on a Event Transmitter. Note that a Event Stream cannot be made
active until a verification process has been completed. As such, a
newly created Event Stream begins with state "verify".
+
|
Create
v
+------+ +----------+
| fail +->Restart---->| verify |
+------+ +----+-----+
^ |
|<----Confirm Fail<----+
| Confirm
| v
| +----------+ +--------+
| | +--->Suspend--->| |
+------Timeout<---+ on | | paused |
| |<--Resume<-----+ |
+-+--------+ +----+---+
| ^ |
Disable Enable |
v | |
+--------+-+ |
| off |<----Limited<-------+
+----------+
Figure 3: Event Stream States at Event Transmitter
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In the above diagram, the following actions impact the state of an
Event Stream. "subStatus" values are shown in the boxes, and change
based on the following actions:
Create
A Event Receiver or an administrator creates a new Event Stream
using SCIM as described in Section 4.2. The initial state is
"verify".
Confirm
The Event Transmitter sends a verification SET to the Event
Receiver which confirms with the correct response as described in
Section 3.4. If it succeeds to deliver, the Event Transmitter
SHALL set state to "on".
Confirm Fail
If the confirmation fails, the Event Transmitter sets the state to
"fail" requiring administrative action to correct the issue and
"Restart".
Timeout
A Event Transmitter who has not been able to deliver a SET over
one or more retries which has reached a limit of attempts
("maxRetries") or time ("maxDeliveryTime") MAY set the Event
Stream state to "fail". In general, the intention is to indicate
the maximum number of retries or time a Event Transmitter is able
to wait until SET event loss begins to occur resulting in the
failed state.
Limited
A paused Event Stream has reached a limit and the Event
Transmitter can no longer retain SETs. The Event Transmitter
changes the state to "off".
Restart
An administrator having corrected the failed delivery condition
modifies the Event Stream state to "verify" (e.g. see
Section 4.3).
Suspend and Resume
An Event Stream MAY be suspended and resumed by updating the Event
Stream state to "paused" or "on". For example, see see
Section 4.3. While suspended, the Event Transmitter MAY retain
undelivered SETs for a period of time. If the Event Transmitter
is no longer able to retain SETs, the Event Stream state SHOULD be
set to "off" to indicate SETs are being lost.
Enable and Disable
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A Event Stream MAY be disabled and enabled by updating the Event
Stream state to "off" or "on". For example, see see Section 4.3.
While the Event Stream is disabled, all SETs that occur at the
Event Transmitter are lost.
2.3. Checking Stream Configuration and Stream State
An Event Receiver MAY check the current status of a Stream with the
Event Transmitter, by performing an HTTP GET using the provided URI
from the Transmitter.
The format of the response is defined by Section TBD [RFC7644].
In addition to the attributes defined in Section 2.1, the response
SHALL include an additional JSON attribute "schemas" with at least a
single value of "urn:ietf:params:scim:schemas:event:2.0:EventStream".
This static attribute is provided to enable optional SCIM client
compatibility and informs the client of the type of JSON object being
returned. Service providers may offer additional attributes by
adding additional schema values as per [RFC7644].
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The response below shows an example response to an HTTP GET, in this
case to "https://example.com/v2/
EventStreams/767aad7853d240debc8e3c962051c1c0".
HTTP/1.1 200 OK
Content-Type: application/json
Location:
https://example.com/v2/EventStreams/767aad7853d240debc8e3c962051c1c0
{
"schemas":["urn:ietf:params:scim:schemas:event:2.0:EventStream"],
"id":"767aad7853d240debc8e3c962051c1c0",
"feedName":"OIDCLogoutFeed",
"feedUri":
"https://example.com/v2/Feeds/88bc00de776d49d5b535ede882d98f74",
"methodUri":"urn:ietf:params:set:method:HTTP:webCallback",
"deliveryUri":"https://notify.examplerp.com/Events",
"aud":"https://sets.myexamplerp.com",
"subStatus":"fail",
"txErr":"connection",
"txErrDesc":"TCP connect error to notify.examplerp.com.",
"maxDeliveryTime":3600,
"minDeliveryInterval":0,
"description":"Logout events from oidc.example.com",
"meta":{
... SCIM meta attributes ...
}
}
Figure 4: Example Stream GET Response
In the above figure, the Event Stream is showing a failed status due
to a TCP connection error. The Event Receiver is able to discover
that its endpoint was unavailable and has been marked failed by the
Event Transmitter. It is expected that the appropriate operations
staff would be alerted and some corrective action would be taken.
The frequency with which Event Receivers should poll the Event Stream
status depends on the following factors:
o The level of technical fault tolerance and availability of the
receiving endpoint.
o A frequency appropriate to the amount of risk that can be
tolerated for lost events. For example, if Security Events are
considered informational, then infrequent (hourly or daily) may be
sufficient.
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In most cases Event Stream status polling can be triggered on a
timeout basis. Event Receivers would typically poll if they have not
received a SET for some period during which SETs would be expected
based on past experience.
3. Data Plane
The data plane represent the HTTP request channel by which the Event
Transmitter delivers SET Events to an Event Receiver.
3.1. Event Delivery Process
When a Security Event occurs, the Feed Provider constructs a SET
token [I-D.ietf-secevent-token] that describes the event. The feed
provider determines the feeds that the event should be distributed
to, and determines which Event Receivers need to be notified.
How SET Events are defined and the process by which events are
identified for Event Receivers is out-of-scope of this specification.
When a SET is available for a Event Receiver, the Feed Transmitter
attempts to deliver the SET based on the Event Receiver's registered
delivery mechanism:
o The Event Transmitter uses an HTTP/1.1 POST to the Event Receiver
endpoint to deliver the SET;
o Or, the Feed Transmitter delivers the event through a different
method not defined by this specification.
Feed Transmitters SHALL NOT be required to main or record SETs. As
such, transmitted SETs SHOULD be self-validating (e.g. signed).
If delivery to any particular Event Receiver has been delayed for an
extended period of time, the Feed Transmitter MAY suspend the
affected Event Stream and even stop maintaining outstanding SETs for
the Event Receiver at its discretion and available resources. See
Event Stream "subState" in Section 2.1.
Upon receiving a SET, the Event Receiver reads the SET and validates
it. Based upon the content of the token, the Event Receiver decides
what, if any, action needs to be taken in response to the received
SET. For example, in response to a SCIM provisioning event
[idevent-scim] indicating a changed resource, the Event Receiver
might perform a SCIM GET request (see Section 3.4 [RFC7644]) to the
affected resource URI in order to confidentially obtain the current
state of the transmitter's affected SCIM resource in order to
reconcile local corresponding state changes.
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The action a Event Receiver takes in response to a SET MAY be
substantially different than merely copying the action of the SET
issuer. A single SET can trigger one or more receiver actions or it
can be ignored. For example, upon receiving notification that a user
resource has been added to a group, the Event Receiver may first
determine that the user does not exist in the Event Receiver's
domain. The Event Receiver translates the event into two actions:
1. Retrieve the user (e.g. using SCIM GET) and then provisions the
user locally. After enabling the user,
2. The Event Receiver then enables the user for the application
associated with membership in the issuer's group.
3.2. Event Stream State
As mentioned in Section 2.1, the attribute "subStatus" defines the
current state of an Event Stream. Figure 3 shows a state diagram for
Event Streams. The following describes that actions taken by the
Event Transmitter based upon "subStatus".
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+--------+----------------------------------------------------------+
| Status | Action |
+--------+----------------------------------------------------------+
| on | Delivery SHALL be attempted based on the method defined |
| | in the Event Stream attribute "methodUri". If the SET |
| | fails to deliver it MAY be retained for a retry delivery |
| | in a minimum of "minDeliveryInterval" seconds. If new |
| | SETs arrive before the interval, the SETs MUST be held |
| | for delivery in order of reception. If this is a repeat |
| | attempt to deliver, the Event Transmitter MAY discard |
| | the SET if "maxRetries" or "maxDeliveryTime" is |
| | exceeded. If a SET is discarded, the Event Transmitter |
| | MAY set "subStatus" to "failed". |
| verify | If the SET is not a Verify SET, the SET MAY be retained |
| | for a retry at the Event Transmitter's discretion. If a |
| | Verify SET fails to deliver, the Event Transmitter SHALL |
| | set "subStatus" to "failed". The Event Transmitter MAY |
| | opt to make multiple attempts to complete a verification |
| | during which status remains as "verify". |
| paused | The SET is held for delivery in a queue. The Event |
| | Transmitter MAY at its own discretion set the Event |
| | Stream state to "failed" if "subStatus" is not returned |
| | to "on" in what the Event Transmitter determines to be a |
| | reasonable amount of time. |
| off | The SET is ignored. |
| fail | The SET is ignored due to a previous unrecoverable |
| | error. |
+--------+----------------------------------------------------------+
Table 1: Delivery Processing By Status
3.3. HTTP POST Delivery
This method allows a feed provider to use HTTP POST (Section 4.3.3
[RFC7231]) to deliver SETs to the registered web callback URI
identified in the Event Stream configuration. The Event Stream
"methodUri" value for this method is
"urn:ietf:params:set:method:HTTP:webCallback".
The SET to be delivered MAY be signed and/or encrypted as defined in
[I-D.ietf-secevent-token].
The Event Stream's "deliveryUri" attribute indicates the location of
a Event Receiver provided endpoint which accepts HTTP POST requests
(e.g. "https://notify.examplerp.com/Events").
The content-type for the HTTP POST is "application/jwt" and SHALL
consists of a single SET token (see [I-D.ietf-secevent-token]).
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WVkcy81ZDc2MDQ1MTZiMWQwODY0MWQ3Njc2ZWU3Il0sInJlc291cmNlVXJpcyI6
WyJodHRwczovL3NjaW0uZXhhbXBsZS5jb20vVXNlcnMvNDRmNjE0MmRmOTZiZDZ
hYjYxZTc1MjFkOSJdLCJldmVudFR5cGVzIjpbIkNSRUFURSJdLCJhdHRyaWJ1dG
VzIjpbImlkIiwibmFtZSIsInVzZXJOYW1lIiwicGFzc3dvcmQiLCJlbWFpbHMiX
SwidmFsdWVzIjp7ImVtYWlscyI6W3sidHlwZSI6IndvcmsiLCJ2YWx1ZSI6Impk
b2VAZXhhbXBsZS5jb20ifV0sInBhc3N3b3JkIjoibm90NHUybm8iLCJ1c2VyTmF
tZSI6Impkb2UiLCJpZCI6IjQ0ZjYxNDJkZjk2YmQ2YWI2MWU3NTIxZDkiLCJuYW
1lIjp7ImdpdmVuTmFtZSI6IkpvaG4iLCJmYW1pbHlOYW1lIjoiRG9lIn19fQ
.
Figure 5: Encoded SET To Be Transmitted
To deliver an event, the Event Transmitter generates an event
delivery message and uses HTTP POST to the EventStream configured
endpoint. The content-type of the message is "application/jwt" and
the expected response type (accept) is "application/json".
POST /Events HTTP/1.1
Host: notify.examplerp.com
Accept: application/json
Content-Type: application/jwt
"eyJhbGciOiJub25lIn0
.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.
Figure 6: Example Web Callback POST Request
Upon receipt of the request, the Event Receiver SHALL validate the
JWT structure of the SET as defined in Section 7.2 [RFC7519]. The
Event Receiver SHALL also validate the SET information as described
in Section 2 [I-D.ietf-secevent-token].
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If the SET is determined to be valid, the Event Receiver SHALL
indicate successful submission by responding with HTTP Status 202 as
"Accepted" (see Section 6.3.3 [RFC7231]).
If SET or JWT is invalid, or there is an HTTP error, the Event
Receiver SHALL respond with the appropriate HTTP error or an HTTP
Status 400 Bad Request error as follows:
+----------+--------------------------------------------------------+
| Err | Description |
| Value | |
+----------+--------------------------------------------------------+
| jwtParse | Invalid or unparsable JWT or JSON structure. |
| jwtHdr | In invalid JWT header was detected. |
| jwtCypto | Unable to parse due to unsupported algorithm. |
| jws | Signature was not validated. |
| jwe | Unable to decrypt JWE encoded data. |
| jwtAud | Invalid audience value. |
| jwtIss | Issuer not recognized. |
| setType | An unexpected event type was received. |
| setParse | Invalid structure was encountered such as inability to |
| | parse SET event payload. |
| setData | SET event claims incomplete or invalid. |
| dup | A duplicate SET was received and has been ignored. |
+----------+--------------------------------------------------------+
Table 2: HTTP Status 400 Errors
The following is a non-normative example of a successful receipt of a
SET.
HTTP/1.1 202 Accepted
Figure 7: Example Successful Delivery Response
An HTTP Status 400 Bad Request response includes a JSON object which
provides details about the error. The JSON object includes the JSON
attributes:
err
A value which is a keyword that describes the error (see Table 2).
description
A human-readable text that provides additional diagnostic
information.
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The following is an example non-normative Bad Request error.
HTTP/1.1 400 Bad Request
Content-Type: application/json
{
"err":"dup",
"description":"SET already received. Ignored."
}
Figure 8: Example Bad Request Response
3.4. Event Stream Verification
To confirm an Event Stream configuration, the Event Transmitter SHALL
send a verification SET to the Event Receiver using the registered
"methodUri" mechanism which in this case is
"urn:ietf:params:set:method:HTTP:webCallback".
The Verify SET contains the following attributes:
events Set with a value of "[[this RFC URL]]#verify".
iss Set to the URI defined in the Event Stream metadata (see
Section 2.1).
aud MUST be set to a value that matches the EventStream "aud" value
(see Section 2.1).
exp A value that indicates the time the verification request will
expire. Once expired, the server will set the Event Stream state
to "fail".
If the Event Stream "confidentialJWK" value was supplied, then the
SET SHOULD be encrypted with the provided key. Successful parsing of
the message confirms that provides confirmation of correct
configuration and possession of keys.
A payload attribute "confirmChallenge" is provided with a JSON String
value that the Event Receiver SHALL echo back in its response. The
intent is to confirm that the Event Receiver has successfully parsed
the SET and is not just echoing back HTTP success.
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A non-normative JSON representation of an event to be sent to a Event
Receiver as a Event Stream confirmation. Note the event is not yet
encoded as a JWT token:
{
"jti": "4d3559ec67504aaba65d40b0363faad8",
"events":["[[this RFC URL]]#verify"],
"iat": 1458496404,
"iss": "https://scim.example.com",
"exp": 1458497000,
"aud":[
"https://scim.example.com/Feeds/98d52461fa5bbc879593b7754",
"https://scim.example.com/Feeds/5d7604516b1d08641d7676ee7"
],
"[[this RFC URL]]#verify":{
"confirmChallenge":"ca2179f4-8936-479a-a76d-5486e2baacd7"
}
}
Figure 9: Example Verification SET with Challenge
The above SET is encoded as a JWT and transmitted to the Event
Receiver as shown in Figure 6.
Upon receiving a verify SET, the Event Receiver SHALL respond with a
JSON object that includes a "challengeResponse" attribute and the
value that was provided in "confirmChallenge". The content type
header is set to "application/json".
The following is a non-normative example response to a Verify SET
received via HTTP/1.1 POST and includes a JSON object containing the
confirmation attribute and value.
HTTP/1.1 200 OK
Content-Type: application/json
{
"challengeResponse":"ca2179f4-8936-479a-a76d-5486e2baacd7"
}
Figure 10: Example Response to Verify SET with Challenge
If the Event Receiver returns a non-matching value or an HTTP status
other than a 200 series response, the Event Stream "state" SHALL be
set to "fail". A declining Event Receiver MAY simply respond with
any 400 series HTTP error (e.g. 404).
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4. Control Plane - Management and Provisioning
This section describes how SCIM [RFC7644] and [RFC7643] MAY be used
to add create, read, update, delete capability to the Control Plane
to enable provisioning and operational management of Event Streams.
In addition to provisioning of Event Streams, it can also be used by
Event Receivers to change or reset the operational state of Event
Streams such as pausing, stopping, or re-enabling after a failure.
SCIM is a protocol used by many security systems for provisioning and
co-ordinating identities and other security subjects in cross-domain
scenarios. SCIM is a RESTful profile of HTTP that is intended to be
implemented by applications that need provisioning and management of
security subjects and is ideal to the task of provisioning related
security event signal systems. Examples of provisioning endpoints
(SCIM service providers) include both Identity Providers and Relying
Party applications (e.g. business and consumer web applications) as
well as security and authorization infrastructure components.
[[Editors Note: At the time of writing, some groups feel a CRUD API
is not required and participants would prefer to manage streams using
an out-of-band workflow approach.]]
4.1. Event Stream Resource Type Definition
To extend SCIM to support Event Streams, requires defining an
"EventStream" SCIM resource type, and implementing the corresponding
RESTful HTTP operations to create, update, retrieve EventStream
Resources. For SCIM service provider capability and schema discovery
(see Sections 3 and 4 [RFC7644]).
The "EventStream" resource type definition is defined as follows:
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{
"schemas": ["urn:ietf:params:scim:schemas:core:2.0:ResourceType"],
"id": "EventStream",
"name": "EventStream",
"endpoint": "/EventStreams",
"description": "Endpoint and event configuration and status for SEC EVENT streams.",
"schema": "urn:ietf:params:scim:schemas:event:2.0:EventStream",
"schemaExtensions": []
}
The resource type above is discoverable in the "/ResourceTypes" and
informs SCIM clients about the endpoint location of EventStream
resources and the SCIM schema used to define the resource. The
corresponding schema for the EventStream resource MAY be retrieved
from the SCIM "/Schemas" endpoint (see Section 3.2 [RFC7644]).
Figure 11: SCIM EventStream Resource Type Definition
To retrieve information about one or more Event Streams, authorized
clients MAY query the "/EventStreams" endpoint as defined in
Section 3.4 [RFC7644].
The example below retrieves a specific "EventStream" resource whose
"id" is "548b7c3f77c8bab33a4fef40".
GET /EventStreams/767aad7853d240debc8e3c962051c1c0
Host: example.com
Accept: application/json
Authorization: Bearer h480djs93hd8
Figure 12: Example SCIM EventStream HTTP GET Request
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The response below shows an example Feed resource that describes an
available feed.
HTTP/1.1 200 OK
Content-Type: application/json
Location:
https://example.com/v2/EventStreams/767aad7853d240debc8e3c962051c1c0
{
"schemas":["urn:ietf:params:scim:schemas:event:2.0:EventStream"],
"id":"767aad7853d240debc8e3c962051c1c0",
"feedName":"OIDCLogoutFeed",
"feedUri":
"https://example.com/v2/Feeds/88bc00de776d49d5b535ede882d98f74",
"methodUri":"urn:ietf:params:set:method:HTTP:webCallback",
"deliveryUri":"https://notify.examplerp.com/Events",
"aud":"https://sets.myexamplerp.com",
"subStatus":"verify",
"maxDeliveryTime":3600,
"minDeliveryInterval":0,
"description":"Logout events from oidc.example.com",
"meta":{
... SCIM meta attributes ...
}
}
Figure 13: Example EventStream HTTP GET Response
In the above example (Figure 13) the EventStream is for the the Feed
"https://example.com/v2/Feeds/88bc00de776d49d5b535ede882d98f74". The
current Event Stream state is "verify" which suggest the Event Stream
Verification (see Section 3.4) process has not yet completed. Since
there is no value for "feedJwk", ) or "confidentialJwk", SETs will be
sent without signing or encryption (plain text).
4.2. Creating A New Event Stream
To subscribe to a feed, the Event Receiver first obtains an
authorization credential authorizing to to make the request (this
process is out of scope of the specification but is often completed
through OAuth). Upon obtaining authorization, the Event Receiver
organization uses the SCIM Create operation (HTTP POST) as defined in
Section 3.3 [RFC7644]. Event Transmitter's Control Plane service MAY
have additional schema requirements for Event Stream creation which
MAY be discovered using SCIM service configuration and schema
discovery, see Section 4 [RFC7644].
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In the following non-normative example, a new EventStream is created.
Note that the Event Transmitter's control-plane automatically assigns
the "id" attribute.
POST /EventStreams
Host: example.com
Accept: application/scim+json
Content-Type: application/scim+json
Authorization: Bearer h480djs93hd8
{
"schemas":["urn:ietf:params:scim:schemas:event:2.0:EventStream"],
"feedName":"OIDCLogoutFeed",
"feedUri":
"https://example.com/v2/Feeds/88bc00de776d49d5b535ede882d98f74",
"methodUri":"urn:ietf:params:set:method:HTTP:webCallback",
"deliveryUri":"https://notify.examplerp.com/Events",
"aud":"https://sets.myexamplerp.com",
"maxDeliveryTime":3600,
"minDeliveryInterval":0,
"description":"Logout events from oidc.example.com"
}
Figure 14: Example Create Event Stream Request
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In following non-normative response, the Event service provider has
automatically assigned a resource location as well as an "id".
Usually upon creation, the initial value of "subStatus" is "pending"
indicating that the Stream Verification process (see Section 3.4) has
not been completed.
HTTP/1.1 201 Created
Content-Type: application/scim+json
Location:
https://example.com/v2/EventStreams/767aad7853d240debc8e3c962051c1c0
{
"schemas":["urn:ietf:params:scim:schemas:event:2.0:EventStream"],
"id":"767aad7853d240debc8e3c962051c1c0",
"feedName":"OIDCLogoutFeed",
"feedUri":
"https://example.com/v2/Feeds/88bc00de776d49d5b535ede882d98f74",
"methodUri":"urn:ietf:params:set:method:HTTP:webCallback",
"deliveryUri":"https://notify.examplerp.com/Events",
"aud":"https://sets.myexamplerp.com",
"subStatus":"verify",
"maxDeliveryTime":3600,
"minDeliveryInterval":0,
"description":"Logout events from oidc.example.com",
"meta":{
... SCIM meta attributes ...
}
}
Figure 15: Example Response to Create EventStream Request
4.3. Updating An Event Stream
Periodically, Event Receivers MAY have need to update an Event Stream
configuration for the purpose of:
o Rotating access credentials or keys
o Updating endpoint configuration
o Making operational changes such as pausing, resetting, or
disabling an Event Stream.
o Other operations (e.g. such as adding or removing subjects) as
defined by profiling Event specifications.
To modify an EventStream, an Event Receiver or authorized management
client MAY use the HTTP PUT operation (see Section 3.5.1 [RFC7644])
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or MAY use the HTTP PATCH operation (see Section 3.5.2 [RFC7644]) if
supported by the Event Transmitter's control plane service. Note
that HTTP PATCH enables more specific changes. This is particularly
useful when updating multi-valued attributes that may contain large
numbers of values. An example of this would be an EventStream that
uses a "members" attribute to define the subjects of the Event
Stream.
In the following non-normative example, the client is requesting that
"subStatus" be changed to "paused" for the EventStream whose path is
identified by the request URI path.
PATCH /EventStreams/767aad7853d240debc8e3c962051c1c0
Host: example.com
Accept: application/scim+json
Content-Type: application/scim+json
Authorization: Bearer h480djs93hd8
{
"schemas":
["urn:ietf:params:scim:api:messages:2.0:PatchOp"],
"Operations": [{
"op":"replace",
"path":"subStatus",
"value":"paused"
}]
}
Upon receiving the request, the Event Transmitter would stop sending
Events to the Receiver. Note that while the request MAY seem complex
it avoids the need for the requestor to have all of the current
EventStream values in order to make a PUT request. In other words,
an HTTP PATCH can be typically done in a single request response
whereas an HTTP POST usually is preceded by an HTTP GET.
Figure 16: Example EventStream PATCH Request
5. Security Considerations
[TO BE COMPLETED]
6. IANA Considerations
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6.1. SCIM Schema Registration
As per the "SCIM Schema URIs for Data Resources" registry established
by Section 10.3 [RFC7643], the following defines and registers the
following SCIM URIs and Resource Types for Feeds and Event Streams.
+---------------------------+----------+--------------+-------------+
| Schema URI | Name | ResourceType | Reference |
+---------------------------+----------+--------------+-------------+
| urn:ietf:params:scim: | SET | EventStream | Section 2.1 |
| schemas:event:2.0: | Event | | |
| EventStream | Stream | | |
+---------------------------+----------+--------------+-------------+
7. References
7.1. Normative References
[I-D.ietf-secevent-token]
Hunt, P., Denniss, W., Ansari, M., and M. Jones, "Security
Event Token (SET)", draft-ietf-secevent-token-00 (work in
progress), January 2017.
[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>.
[RFC5988] Nottingham, M., "Web Linking", RFC 5988,
DOI 10.17487/RFC5988, October 2010,
<http://www.rfc-editor.org/info/rfc5988>.
[RFC7231] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Semantics and Content", RFC 7231,
DOI 10.17487/RFC7231, June 2014,
<http://www.rfc-editor.org/info/rfc7231>.
[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>.
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7.2. Informative References
[idevent-scim]
Oracle Corporation, "SCIM Event Extensions (work in
progress)".
[openid-connect-core]
NRI, "OpenID Connect Core 1.0", Nov 2014.
[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>.
[RFC7643] Hunt, P., Ed., Grizzle, K., Wahlstroem, E., and C.
Mortimore, "System for Cross-domain Identity Management:
Core Schema", RFC 7643, DOI 10.17487/RFC7643, September
2015, <http://www.rfc-editor.org/info/rfc7643>.
[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>.
[saml-core-2.0]
Internet2, "Assertions and Protocols for the OASIS
Security Assertion Markup Language (SAML) V2.0", March
2005.
Appendix A. Acknowledgments
The editors would like to thanks the members of the SCIM WG which
began discussions of provisioning events starting with: draft-hunt-
scim-notify-00 in 2015.
The editor would like to thank the participants in the the SECEVENTS
working group for their support of this specification.
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Appendix B. Change Log
Draft 00 - PH - First Draft based on reduced version of draft-hunt-
idevent-distribution
Draft 01 - PH -
o Reworked terminology to match new WG Transmitter/Receiver terms
o Reworked sections into Data Plane vs. Control Plane
o Removed method transmission registry in order to simplify the
specification
o Made Create, Update operations optional for Control Plane (Read is
MTI)
Authors' Addresses
Phil Hunt (editor)
Oracle Corporation
Email: phil.hunt@yahoo.com
Marius Scurtescu
Google
Email: mscurtescu@google.com
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