Network Working Group A. Backman, Ed.
Internet-Draft Amazon
Intended status: Standards Track M. Jones, Ed.
Expires: September 11, 2019 Microsoft
M. Scurtescu
Coinbase
M. Ansari
Cisco
A. Nadalin
Microsoft
March 10, 2019
Poll-Based Security Event Token (SET) Delivery Using HTTP
draft-ietf-secevent-http-poll-02
Abstract
This specification defines how a series of Security Event Tokens
(SETs) may be delivered to an intended recipient using HTTP POST over
TLS initiated as a poll by the recipient. The specification also
defines how delivery can be assured, subject to the SET Recipient'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
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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 11, 2019.
Copyright Notice
Copyright (c) 2019 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
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Table of Contents
1. Introduction and Overview . . . . . . . . . . . . . . . . . . 2
1.1. Notational Conventions . . . . . . . . . . . . . . . . . 3
1.2. Definitions . . . . . . . . . . . . . . . . . . . . . . . 3
2. SET Delivery . . . . . . . . . . . . . . . . . . . . . . . . 3
2.1. Polling Delivery using HTTP . . . . . . . . . . . . . . . 4
2.2. Polling HTTP Request Attributes . . . . . . . . . . . . . 4
2.3. Polling HTTP Response Attributes . . . . . . . . . . . . 5
2.4. Poll Request . . . . . . . . . . . . . . . . . . . . . . 6
2.4.1. Poll Only Request . . . . . . . . . . . . . . . . . . 7
2.4.2. Acknowledge Only Request . . . . . . . . . . . . . . 8
2.4.3. Poll with Acknowledgement . . . . . . . . . . . . . . 8
2.4.4. Poll with Acknowledgement and Errors . . . . . . . . 9
2.5. Poll Response . . . . . . . . . . . . . . . . . . . . . . 10
2.6. Error Response Handling . . . . . . . . . . . . . . . . . 12
3. Authentication and Authorization . . . . . . . . . . . . . . 12
3.1. Use of Tokens as Authorizations . . . . . . . . . . . . . 13
4. Security Considerations . . . . . . . . . . . . . . . . . . . 14
4.1. Authentication Using Signed SETs . . . . . . . . . . . . 14
4.2. HTTP Considerations . . . . . . . . . . . . . . . . . . . 14
4.3. TLS Support Considerations . . . . . . . . . . . . . . . 14
4.4. Access Token Considerations . . . . . . . . . . . . . . . 15
4.4.1. Bearer Token Considerations . . . . . . . . . . . . . 15
5. Privacy Considerations . . . . . . . . . . . . . . . . . . . 15
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 16
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 16
7.1. Normative References . . . . . . . . . . . . . . . . . . 16
7.2. Informative References . . . . . . . . . . . . . . . . . 17
Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 18
Appendix B. Change Log . . . . . . . . . . . . . . . . . . . . . 18
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 19
1. Introduction and Overview
This specification defines how a stream of Security Event Tokens
(SETs) [RFC8417] can be transmitted to an intended SET Recipient
using HTTP [RFC7231] over TLS. The specification defines a method to
poll for SETs using HTTP POST.
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1.1. Notational Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
"OPTIONAL" in this document are to be interpreted as described in BCP
14 [RFC2119] [RFC8174] when, and only when, they appear in all
capitals, as shown here.
Throughout this document, all figures MAY contain spaces and extra
line wrapping for readability and due to space limitations.
1.2. Definitions
This specification utilizes terminology defined in [RFC8417], as well
as the terms defined below:
SET Transmitter
An entity that delivers SETs in its possession to one or more SET
Recipients.
2. SET Delivery
When an event occurs, the SET Transmitter constructs a SET [RFC8417]
that describes the event. The SET Transmitter determines the SET
Recipients that the SET should be distributed to.
How SETs are defined and the process by which events are identified
for SET Recipients is out of scope of this specification.
When a SET is available for a SET Recipient, the SET Transmitter
attempts to deliver the SET by queueing s the SET in a buffer so that
a SET Recipient can poll for SETs using HTTP/1.1 POST.
In Poll-Based SET Delivery Using HTTP, zero or more SETs are
delivered in a JSON [RFC8259] document to a SET Recipient in response
to an HTTP POST request to the SET Transmitter. Then in a following
request, the SET Recipient acknowledges received SETs and can poll
for more. All requests and responses are JSON documents and use a
"Content-Type" of "application/json", as described in Section 2.1.
After successful (acknowledged) SET delivery, SET Transmitters are
not be required to retain or record SETs for recovery. Once a SET is
acknowledged, the SET Recipient SHALL be responsible for retention
and recovery.
Transmitted SETs SHOULD be self-validating (e.g., signed) if there is
a requirement to verify they were issued by the SET Transmitter at a
later date when de-coupled from the original delivery where
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authenticity could be checked via the HTTP or TLS mutual
authentication.
Upon receiving a SET, the SET Recipient reads the SET and validates
it. The SET Recipient MUST acknowledge receipt to the SET
Transmitter.
The SET Recipient SHALL NOT use the event acknowledgement mechanism
to report event errors other than relating to the parsing and
validation of the SET.
2.1. Polling Delivery using HTTP
This method allows a SET Recipient to use HTTP POST (Section 4.3.3 of
[RFC7231]) to acknowledge SETs and to check for and receive zero or
more SETs. Requests MAY be made at a periodic interval (short
polling) or requests MAY wait, pending availability of new SETs using
long polling, per Section 2 of [RFC6202].
The delivery of SETs in this method is facilitated by HTTP POST
requests initiated by the SET Recipient in which:
o The SET Recipient makes a request for available SETs using an HTTP
POST to a pre-arranged endpoint provided by the SET Transmitter.
Or,
o After validating previously received SETs, the SET Recipient
initiates another poll request using HTTP POST that includes
acknowledgement of previous SETs and waits for the next batch of
SETs.
The purpose of the acknowledgement is to inform the SET Transmitter
that delivery has succeeded and redelivery is no longer required.
Before acknowledgement, SET Recipients SHOULD ensure that received
SETs have been validated and retained in a manner appropriate to the
recipient's requirements. The level and method of retention of SETs
by SET Recipients is out of scope of this specification.
2.2. Polling HTTP Request Attributes
When initiating a poll request, the SET Recipient constructs a JSON
document that consists of polling request parameters and SET
acknowledgement parameters in the form of JSON attributes. The
request payloads are delivered in a JSON document, as described in
Section 2.4 and Section 2.5.
When making a request, the HTTP header "Content-Type" is set to
"application/json".
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The following JSON attributes are used in a polling request:
Request Processing Parameters
maxEvents
An OPTIONAL JSON integer value indicating the maximum number of
unacknowledged SETs that SHOULD be returned. If more than the
maximum number of SETs are available, the oldest SETs available
SHOULD be returned first. A value of "0" MAY be used by SET
Recipients that would like to perform an acknowledge only
request. This enables the Recipient to use separate HTTP
requests for acknowledgement and reception of SETs. If this
parameter is omitted, no limit is placed on the number of SETs
to be returned.
returnImmediately
An OPTIONAL JSON boolean value that indicates the SET
Transmitter SHOULD return an immediate response even if no
results are available (short polling). The default value is
"false" indicates the request is to be treated as an HTTP Long
Poll, per Section 2 of [RFC6202]. The timeout for the request
is part of the configuration between the participants, which is
out of scope of this specification.
SET Acknowledgment Parameters
ack
Which is an array of Strings that each correspond to the "jti"
of a successfully received SET. If there are no outstanding
SETs to acknowledge, the attribute MAY be omitted. When
acknowledging a SET, the SET Transmitter is released from any
obligation to retain the SET (e.g., for a future retry to
receive).
setErrs
A JSON Object that contains one or more nested JSON attributes
that correspond to the "jti" of each invalid SET received. The
value of each is a JSON object whose contents is an "err"
attribute and "description" attribute whose value correspond to
the errors described in Section 2.6.
2.3. Polling HTTP Response Attributes
In response to a poll request, the SET Transmitter checks for
available SETs and responds with a JSON document containing the
following JSON attributes:
sets
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A JSON object that contains zero or more nested JSON attributes.
Each nested attribute corresponds to the "jti" of a SET to be
delivered and whose value is a JSON String containing the value of
the encoded corresponding SET. If there are no outstanding SETs
to be transmitted, the JSON object SHALL be empty.
moreAvailable
A JSON boolean value that indicates if more unacknowledged SETs
are available to be returned.
When making a response, the HTTP header "Content-Type" is set to
"application/json".
2.4. Poll Request
The SET Recipient performs an HTTP POST (see Section 4.3.4 of
[RFC7231]) to a pre-arranged polling endpoint URI to check for SETs
that are available. Because the SET Recipient has no prior SETs to
acknowledge, the "ack" and "errs" request parameters are omitted.
If after a period of time, negotiated between the SET Transmitter and
Recipient, a SET Transmitter MAY redeliver SETs it has previously
delivered. The SET Recipient SHOULD accept repeat SETs and
acknowledge the SETs regardless of whether the Recipient believes it
has already acknowledged the SETs previously. A SET Transmitter MAY
limit the number of times it attempts to deliver a SET.
If the SET Recipient has received SETs from the SET Transmitter, the
SET Recipient SHOULD parse and validate received SETs to meet its own
requirements and SHOULD acknowledge receipt in a timely fashion
(e.g., seconds or minutes) so that the SET Transmitter can mark the
SETs as received. SET Recipients SHOULD acknowledge receipt before
taking any local actions based on the SETs to avoid unnecessary delay
in acknowledgement, where possible.
Poll requests have three variations:
Poll Only
In which a SET Recipient asks for the next set of events where no
previous SET deliveries are acknowledged (such as in the initial
poll request).
Acknowledge Only
In which a SET Recipient sets the "maxEvents" attribute to "0"
along with "ack" and "err" attributes indicating the SET Recipient
is acknowledging previously received SETs and does not want to
receive any new SETs in response to the request.
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Combined Acknowledge and Poll
In which a SET Recipient is both acknowledging previously received
SETs using the "ack" and "err" attributes and will wait for the
next group of SETs in the SET Transmitters response.
2.4.1. Poll Only Request
In the case where no SETs were received in a previous poll (see
Figure 7), the SET Recipient simply polls without acknowledgement
parameters ("sets" and "setErrs").
The following is an example request made by a SET Recipient that has
no outstanding SETs to acknowledge and is polling for available SETs.
The following is a non-normative example poll request to the
endpoint: "https://nofity.exampleidp.com/Events".
POST /Events HTTP/1.1
Host: notify.exampleidp.com
Authorization: Bearer h480djs93hd8
Accept: application/json
{
"returnImmediately": true
}
Figure 1: Example Initial Poll Request
A SET Recipient can poll using default parameter values by passing an
empty JSON object.
The following is a non-normative example default poll request to the
endpoint: "https://nofity.exampleidp.com/Events".
POST /Events HTTP/1.1
Host: notify.exampleidp.com
Authorization: Bearer h480djs93hd8
Accept: application/json
{}
Figure 2: Example Default Poll Request
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2.4.2. Acknowledge Only Request
In this variation, the SET Recipient acknowledges previously received
SETs and indicates it does not want to receive SETs in response by
setting the "maxEvents" attribute to "0".
This variation might be used, for instance, when a SET Recipient
needs to acknowledge received SETs independently (e.g., on separate
threads) from the process of receiving SETs.
The following is a non-normative example poll with acknowledgement of
SETs received (for example as shown in Figure 6).
POST /Events HTTP/1.1
Host: notify.exampleidp.com
Authorization: Bearer h480djs93hd8
Content-Type: application/json
Authorization: Bearer h480djs93hd8
{
"ack": [
"4d3559ec67504aaba65d40b0363faad8",
"3d0c3cf797584bd193bd0fb1bd4e7d30"
],
"maxEvents": 0,
"returnImmediately": true
}
Figure 3: Example Acknowledge Only Request
2.4.3. Poll with Acknowledgement
This variation allows a recipient thread to simultaneously
acknowledge previously received SETs and wait for the next group of
SETs in a single request.
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The following is a non-normative example poll with acknowledgement of
SETs received in Figure 6.
POST /Events HTTP/1.1
Host: notify.exampleidp.com
Authorization: Bearer h480djs93hd8
Content-Type: application/json
Authorization: Bearer h480djs93hd8
{
"ack": [
"4d3559ec67504aaba65d40b0363faad8",
"3d0c3cf797584bd193bd0fb1bd4e7d30"
],
"returnImmediately": false
}
Figure 4: Example Poll with Acknowledgement and No Errors
In the above acknowledgement, the SET Recipient has acknowledged
receipt of two SETs and has indicated it wants to wait until the next
SET is available.
2.4.4. Poll with Acknowledgement and Errors
In the case where errors were detected in previously delivered SETs,
the SET Recipient MAY use the "setErrs" attribute to communicate the
errors in the following poll request.
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The following is a non-normative example of a response acknowledging
one successfully received SET and one SET with an error from the two
SETs received in in Figure 6.
POST /Events HTTP/1.1
Host: notify.exampleidp.com
Authorization: Bearer h480djs93hd8
Content-Type: application/json
Authorization: Bearer h480djs93hd8
{
"ack": ["3d0c3cf797584bd193bd0fb1bd4e7d30"],
"setErrs": {
"4d3559ec67504aaba65d40b0363faad8": {
"err": "jwtAud",
"description": "The audience value was invalid."
}
},
"returnImmediately": true
}
Figure 5: Example Poll Acknowledgement with Error
2.5. Poll Response
In response to a poll request, the service provider MAY respond
immediately if SETs are available to be delivered. If no SETs are
available at the time of the request, the SET Transmitter SHALL delay
responding until a SET is available or the timeout interval has
elapsed unless the poll request parameter "returnImmediately" is
"true".
As described in Section 2.3, a JSON document is returned containing a
number of attributes including "sets" which SHALL contain zero or
more SETs.
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The following is a non-normative example response to the request
shown Section 2.4. This example shows two SETs are returned.
HTTP/1.1 200 OK
Content-Type: application/json
Location: https://notify.exampleidp/Events
{
"sets": {
"4d3559ec67504aaba65d40b0363faad8":
"eyJhbGciOiJub25lIn0.
eyJqdGkiOiI0ZDM1NTllYzY3NTA0YWFiYTY1ZDQwYjAzNjNmYWFkOCIsImlhdCI6MTQ
1ODQ5NjQwNCwiaXNzIjoiaHR0cHM6Ly9zY2ltLmV4YW1wbGUuY29tIiwiYXVkIjpbIm
h0dHBzOi8vc2NpbS5leGFtcGxlLmNvbS9GZWVkcy85OGQ1MjQ2MWZhNWJiYzg3OTU5M
2I3NzU0IiwiaHR0cHM6Ly9zY2ltLmV4YW1wbGUuY29tL0ZlZWRzLzVkNzYwNDUxNmIx
ZDA4NjQxZDc2NzZlZTciXSwiZXZlbnRzIjp7InVybjppZXRmOnBhcmFtczpzY2ltOmV
2ZW50OmNyZWF0ZSI6eyJyZWYiOiJodHRwczovL3NjaW0uZXhhbXBsZS5jb20vVXNlcn
MvNDRmNjE0MmRmOTZiZDZhYjYxZTc1MjFkOSIsImF0dHJpYnV0ZXMiOlsiaWQiLCJuY
W1lIiwidXNlck5hbWUiLCJwYXNzd29yZCIsImVtYWlscyJdfX19.",
"3d0c3cf797584bd193bd0fb1bd4e7d30":
"eyJhbGciOiJub25lIn0.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."
}
}
Figure 6: Example Poll Response
In the above example, a two SETs whose "jti" are
"4d3559ec67504aaba65d40b0363faad8" and
"3d0c3cf797584bd193bd0fb1bd4e7d30" are delivered.
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The following is a non-normative example response to the request
shown Section 2.4 showing no new SETs or unacknowledged SETs are
available.
HTTP/1.1 200 OK
Content-Type: application/json
Location: https://notify.exampleidp/Events
{
"sets": {}
}
Figure 7: Example No SETs Poll Response
Upon receiving the JSON document (e.g., as shown in Figure 6), the
SET Recipient parses and verifies the received SETs and notifies the
SET Transmitter via the next poll request to the SET Transmitter, as
described in Section 2.4.3 or Section 2.4.4.
2.6. Error Response Handling
If a SET is invalid, error codes from the IANA "Security Event Token
Delivery Error Codes" registry established by
[I-D.ietf-secevent-http-push] are used in error responses. An error
response SHALL include a JSON object that provides details about the
error. The JSON object includes the JSON attributes:
err
A value from the IANA "Security Event Token Delivery Error Codes"
registry that identifies the error.
description
A human-readable string that provides additional diagnostic
information.
When included as part of a batch of SETs, the above JSON is included
as part of the "setErrs" attribute, as defined in Section 2.3 and
Section 2.4.4.
3. Authentication and Authorization
The SET delivery method described in this specification is based upon
HTTP and depends on the use of TLS and/or standard HTTP
authentication and authorization schemes as per [RFC7235]. For
example, the following methodologies could be used among others:
TLS Client Authentication
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Event delivery endpoints MAY request TLS mutual client
authentication, per Section 7.3 of [RFC5246].
Bearer Tokens
Bearer tokens [RFC6750] MAY be used when combined with TLS and a
token framework such as OAuth 2.0 [RFC6749]. For security
considerations regarding the use of bearer tokens in SET delivery,
see Section 4.4.1.
Basic Authentication
Use of HTTP BASIC authentication should be avoided due to its use
of a single factor that is based upon a relatively static,
symmetric secret. When used, implementers SHOULD combine the use
of basic authentication with other factors. The security
considerations of HTTP BASIC are well documented in [RFC7617] and
SHOULD be considered along with using signed SETs (see SET Payload
Authentication below).
As per Section 4.1 of [RFC7235], a SET delivery endpoint SHALL
indicate supported HTTP authentication schemes via the "WWW-
Authenticate" header.
Because SET Delivery describes a simple function, authorization for
the ability to pick-up or deliver SETs can be derived by considering
the identity of the SET issuer, or via an authentication method
above. This specification considers authentication as a feature to
prevent denial-of-service attacks. Because SETs are not commands,
SET Recipients are free to ignore SETs that are not of interest after
acknowledging their receipt.
For illustrative purposes only, SET delivery examples show an OAuth2
bearer token value [RFC6750] in the authorization header. This is
not intended to imply that bearer tokens are preferred. However, the
use of bearer tokens in the specification does reflect common
practice.
3.1. Use of Tokens as Authorizations
When using bearer tokens or proof-of-possession tokens that represent
an authorization grant such as issued by OAuth (see [RFC6749]),
implementers SHOULD consider the type of authorization granted, any
authorized scopes (see Section 3.3 of [RFC6749]), and the security
subject(s) that SHOULD be mapped from the authorization when
considering local access control rules. Section 6 of the OAuth
Assertions draft [RFC7521], documents common scenarios for
authorization including:
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o Clients using an assertion to authenticate and/or act on behalf of
itself;
o Clients acting on behalf of a user; and,
o A Client acting on behalf of an anonymous user (e.g., see next
section).
When using OAuth access tokens, implementers MUST take into account
the threats and countermeasures documented in the security
considerations for the use of client authorizations (see Section 8 of
[RFC7521]). When using other token formats or frameworks,
implementers MUST take into account similar threats and
countermeasures, especially those documented by the relevant
specifications.
4. Security Considerations
4.1. Authentication Using Signed SETs
In scenarios where HTTP authorization or TLS mutual authentication
are not used or are considered weak, JWS signed SETs SHOULD be used
(see [RFC7515] and Security Considerations [RFC8417]). This enables
the SET Recipient to validate that the SET issuer is authorized to
deliver the SET.
4.2. HTTP Considerations
SET delivery depends on the use of Hypertext Transfer Protocol and
thus subject to the security considerations of HTTP Section 9 of
[RFC7230] and its related specifications.
As stated in Section 2.7.1 of [RFC7230], an HTTP requestor MUST NOT
generate the "userinfo" (i.e., username and password) component (and
its "@" delimiter) when an "http" URI reference is generated with a
message as they are now disallowed in HTTP.
4.3. TLS Support Considerations
SETs may contain sensitive information that is considered PII (e.g.,
subject claims). In such cases, SET Transmitters and SET Recipients
MUST encrypt the SET, either with a transport-layer security
mechanism, with JWE [RFC7516], or both. Event delivery endpoints
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].
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4.4. Access Token Considerations
When using access tokens such as those issued by OAuth 2.0 [RFC6749],
implementers MUST take into account threats and countermeasures
documented in Section 8 of [RFC7521].
4.4.1. Bearer Token Considerations
Due to the possibility of interception, Bearer tokens MUST be
exchanged using TLS.
Bearer tokens MUST have a limited lifetime that can be determined
directly or indirectly (e.g., by checking with a validation service)
by the service provider. By expiring tokens, clients are forced to
obtain a new token (which usually involves re-authentication) for
continued authorized access. For example, in OAuth2, a client MAY
use an OAuth refresh token to obtain a new bearer token after
authenticating to an authorization server, per Section 6 of
[RFC6749].
Implementations supporting OAuth bearer tokens need to factor in
security considerations of this authorization method [RFC7521].
Since security is only as good as the weakest link, implementers also
need to consider authentication choices coupled with OAuth bearer
tokens. The security considerations of the default authentication
method for OAuth bearer tokens, HTTP BASIC, are well documented in
[RFC7617], therefore implementers are encouraged to prefer stronger
authentication methods. Designating the specific methods of
authentication and authorization are out of scope for the delivery of
SETs, however this information is provided as a resource to
implementers.
5. Privacy Considerations
If a SET needs to be retained for audit purposes, a JWS signature MAY
be used to provide verification of its authenticity.
SET Transmitters SHOULD attempt to deliver SETs that are 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, SET
Transmitters and Recipients MUST have the appropriate legal
agreements and user consent or terms of service in place.
The propagation of subject identifiers can be perceived as personally
identifiable information. Where possible, SET Transmitters and
Recipients SHOULD devise approaches that prevent propagation, for
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example, the passing of a hash value that requires the subscriber to
already know the subject.
6. IANA Considerations
There are no IANA considerations.
7. References
7.1. Normative References
[I-D.ietf-secevent-http-push]
Backman, A., Jones, M., Scurtescu, M., Ansari, M., and A.
Nadalin, "Push-Based Security Event Token (SET) Delivery
Using HTTP", draft-ietf-secevent-http-push-04 (work in
progress), January 2019.
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119,
DOI 10.17487/RFC2119, March 1997,
<https://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,
<https://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,
<https://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, <https://www.rfc-editor.org/info/rfc6125>.
[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,
<https://www.rfc-editor.org/info/rfc7231>.
[RFC7515] Jones, M., Bradley, J., and N. Sakimura, "JSON Web
Signature (JWS)", RFC 7515, DOI 10.17487/RFC7515, May
2015, <https://www.rfc-editor.org/info/rfc7515>.
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[RFC7516] Jones, M. and J. Hildebrand, "JSON Web Encryption (JWE)",
RFC 7516, DOI 10.17487/RFC7516, May 2015,
<https://www.rfc-editor.org/info/rfc7516>.
[RFC7519] Jones, M., Bradley, J., and N. Sakimura, "JSON Web Token
(JWT)", RFC 7519, DOI 10.17487/RFC7519, May 2015,
<https://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, <https://www.rfc-editor.org/info/rfc7525>.
[RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
May 2017, <https://www.rfc-editor.org/info/rfc8174>.
[RFC8259] Bray, T., Ed., "The JavaScript Object Notation (JSON) Data
Interchange Format", STD 90, RFC 8259,
DOI 10.17487/RFC8259, December 2017,
<https://www.rfc-editor.org/info/rfc8259>.
[RFC8417] Hunt, P., Ed., Jones, M., Denniss, W., and M. Ansari,
"Security Event Token (SET)", RFC 8417,
DOI 10.17487/RFC8417, July 2018,
<https://www.rfc-editor.org/info/rfc8417>.
7.2. Informative References
[RFC3339] Klyne, G. and C. Newman, "Date and Time on the Internet:
Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002,
<https://www.rfc-editor.org/info/rfc3339>.
[RFC6202] Loreto, S., Saint-Andre, P., Salsano, S., and G. Wilkins,
"Known Issues and Best Practices for the Use of Long
Polling and Streaming in Bidirectional HTTP", RFC 6202,
DOI 10.17487/RFC6202, April 2011,
<https://www.rfc-editor.org/info/rfc6202>.
[RFC6749] Hardt, D., Ed., "The OAuth 2.0 Authorization Framework",
RFC 6749, DOI 10.17487/RFC6749, October 2012,
<https://www.rfc-editor.org/info/rfc6749>.
[RFC6750] Jones, M. and D. Hardt, "The OAuth 2.0 Authorization
Framework: Bearer Token Usage", RFC 6750,
DOI 10.17487/RFC6750, October 2012,
<https://www.rfc-editor.org/info/rfc6750>.
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[RFC7230] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Message Syntax and Routing",
RFC 7230, DOI 10.17487/RFC7230, June 2014,
<https://www.rfc-editor.org/info/rfc7230>.
[RFC7235] Fielding, R., Ed. and J. Reschke, Ed., "Hypertext Transfer
Protocol (HTTP/1.1): Authentication", RFC 7235,
DOI 10.17487/RFC7235, June 2014,
<https://www.rfc-editor.org/info/rfc7235>.
[RFC7521] Campbell, B., Mortimore, C., Jones, M., and Y. Goland,
"Assertion Framework for OAuth 2.0 Client Authentication
and Authorization Grants", RFC 7521, DOI 10.17487/RFC7521,
May 2015, <https://www.rfc-editor.org/info/rfc7521>.
[RFC7617] Reschke, J., "The 'Basic' HTTP Authentication Scheme",
RFC 7617, DOI 10.17487/RFC7617, September 2015,
<https://www.rfc-editor.org/info/rfc7617>.
Appendix A. Acknowledgments
The editors would like to thank the members of the SCIM working
group, which began discussions of provisioning events starting with
draft-hunt-scim-notify-00 in 2015.
The editors would like to thank Phil Hunt and the other the authors
of draft-ietf-secevent-delivery-02, on which this draft is based.
The editors would like to thank the participants in the SecEvents
working group for their contributions to this specification.
Appendix B. Change Log
[[ to be removed by the RFC Editor before publication as an RFC ]]
Draft 00 - AB - Based on draft-ietf-secevent-delivery-02 with the
following additions:
o Renamed to "Poll-Based SET Token Delivery Using HTTP"
o Removed references to the HTTP Push delivery method.
Draft 01 - mbj:
o Addressed problems identified in my 18-Jul-18 review message
titled "Issues for both the Push and Poll Specs".
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o Changes to align terminology with RFC 8417, for instance, by using
the already defined term SET Recipient rather than SET Receiver.
o Applied editorial and minor normative corrections.
o Updated Marius' contact information.
o Begun eliminating redundancies between this specification and
"Push-Based Security Event Token (SET) Delivery Using HTTP"
[I-D.ietf-secevent-http-push], referencing, rather that
duplicating common normative text.
Draft 02 - mbj:
o Removed vestigial language remaining from when the push and poll
delivery methods were defined in a common specification.
o Replaced remaining uses of the terms Event Transmitter and Event
Recipient with the correct terms SET Transmitter and SET
Recipient.
o Removed uses of the unnecessary term "Event Stream".
o Removed dependencies between the semantics of "maxEvents" and
"returnImmediately".
o Said that PII in SETs is to be encrypted with TLS, JWE, or both.
o Corrected grammar and spelling errors.
Authors' Addresses
Annabelle Backman (editor)
Amazon
Email: richanna@amazon.com
Michael B. Jones (editor)
Microsoft
Email: mbj@microsoft.com
URI: http://self-issued.info/
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Marius Scurtescu
Coinbase
Email: marius.scurtescu@coinbase.com
Morteza Ansari
Cisco
Email: morteza.ansari@cisco.com
Anthony Nadalin
Microsoft
Email: tonynad@microsoft.com
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