ACE Working Group M. Tiloca
Internet-Draft R. Hoeglund
Intended status: Standards Track RISE AB
Expires: May 6, 2021 P. van der Stok
Consultant
F. Palombini
K. Hartke
Ericsson AB
November 02, 2020
Admin Interface for the OSCORE Group Manager
draft-ietf-ace-oscore-gm-admin-01
Abstract
Group communication for CoAP can be secured using Group Object
Security for Constrained RESTful Environments (Group OSCORE). A
Group Manager is responsible to handle the joining of new group
members, as well as to manage and distribute the group key material.
This document defines a RESTful admin interface at the Group Manager,
that allows an Administrator entity to create and delete OSCORE
groups, as well as to retrieve and update their configuration. The
ACE framework for Authentication and Authorization is used to enforce
authentication and authorization of the Administrator at the Group
Manager. Protocol-specific transport profiles of ACE are used to
achieve communication security, proof-of-possession and server
authentication.
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 May 6, 2021.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 4
2. Group Administration . . . . . . . . . . . . . . . . . . . . 6
2.1. Getting Access to the Group Manager . . . . . . . . . . . 6
2.2. Managing OSCORE Groups . . . . . . . . . . . . . . . . . 7
2.3. Collection Representation . . . . . . . . . . . . . . . . 8
2.4. Discovery . . . . . . . . . . . . . . . . . . . . . . . . 8
3. Group Configurations . . . . . . . . . . . . . . . . . . . . 9
3.1. Group Configuration Representation . . . . . . . . . . . 9
3.1.1. Configuration Properties . . . . . . . . . . . . . . 9
3.1.2. Status Properties . . . . . . . . . . . . . . . . . . 11
3.2. Default Values . . . . . . . . . . . . . . . . . . . . . 12
3.2.1. Configuration Parameters . . . . . . . . . . . . . . 12
3.2.2. Status Parameters . . . . . . . . . . . . . . . . . . 12
4. Interactions with the Group Manager . . . . . . . . . . . . . 13
4.1. Retrieve the Full List of Groups Configurations . . . . . 13
4.2. Retrieve a List of Group Configurations by Filters . . . 14
4.3. Create a New Group Configuration . . . . . . . . . . . . 15
4.4. Retrieve a Group Configuration . . . . . . . . . . . . . 20
4.5. Retrieve Part of a Group Configuration by Filters . . . . 22
4.6. Overwrite a Group Configuration . . . . . . . . . . . . . 24
4.6.1. Effects on Joining Nodes . . . . . . . . . . . . . . 26
4.6.2. Effects on the Group Members . . . . . . . . . . . . 27
4.7. Delete a Group Configuration . . . . . . . . . . . . . . 28
4.7.1. Effects on the Group Members . . . . . . . . . . . . 29
5. Security Considerations . . . . . . . . . . . . . . . . . . . 29
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 30
6.1. ACE Groupcomm Parameters Registry . . . . . . . . . . . . 30
6.2. Resource Types . . . . . . . . . . . . . . . . . . . . . 32
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 32
7.1. Normative References . . . . . . . . . . . . . . . . . . 32
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7.2. Informative References . . . . . . . . . . . . . . . . . 34
Appendix A. Document Updates . . . . . . . . . . . . . . . . . . 35
A.1. Version -00 to -01 . . . . . . . . . . . . . . . . . . . 35
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 35
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 36
1. Introduction
The Constrained Application Protocol (CoAP) [RFC7252] can be used in
group communication environments where messages are also exchanged
over IP multicast [I-D.ietf-core-groupcomm-bis]. Applications
relying on CoAP can achieve end-to-end security at the application
layer by using Object Security for Constrained RESTful Environments
(OSCORE) [RFC8613], and especially Group OSCORE
[I-D.ietf-core-oscore-groupcomm] in group communication scenarios.
When group communication for CoAP is protected with Group OSCORE,
nodes are required to explicitly join the correct OSCORE group. To
this end, a joining node interacts with a Group Manager (GM) entity
responsible for that group, and retrieves the required key material
to securely communicate with other group members using Group OSCORE.
The method in [I-D.ietf-ace-key-groupcomm-oscore] specifies how nodes
can join an OSCORE group through the respective Group Manager. Such
a method builds on the ACE framework for Authentication and
Authorization [I-D.ietf-ace-oauth-authz], so ensuring a secure
joining process as well as authentication and authorization of
joining nodes (clients) at the Group Manager (resource server).
In some deployments, the application running on the Group Manager may
know when a new OSCORE group has to be created, as well as how it
should be configured and later on updated or deleted, e.g. based on
the current application state or on pre-installed policies. In this
case, the Group Manager application can create and configure OSCORE
groups when needed, by using a local application interface. However,
this requires the Group Manager to be application-specific, which in
turn leads to error prone deployments and is poorly flexible.
In other deployments, a separate Administrator entity, such as a
Commissioning Tool, is directly responsible for creating and
configuring the OSCORE groups at a Group Manager, as well as for
maintaining them during their whole lifetime until their deletion.
This allows the Group Manager to be agnostic of the specific
applications using secure group communication.
This document specifies a RESTful admin interface at the Group
Manager, intended for an Administrator as a separate entity external
to the Group Manager and its application. The interface allows the
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Administrator to create and delete OSCORE groups, as well as to
configure and update their configuration.
Interaction examples are provided, in Link Format [RFC6690] and CBOR
[I-D.ietf-cbor-7049bis], as well as in CoRAL [I-D.ietf-core-coral].
While all the CoRAL examples use the CoRAL textual serialization
format, the CBOR or JSON [RFC8259] binary serialization format is
used when sending such messages on the wire.
The ACE framework is used to ensure authentication and authorization
of the Administrator (client) at the Group Manager (resource server).
In order to achieve communication security, proof-of-possession and
server authentication, the Administrator and the Group Manager
leverage protocol-specific transport profiles of ACE, such as
[I-D.ietf-ace-oscore-profile][I-D.ietf-ace-dtls-authorize]. These
include also possible forthcoming transport profiles that comply with
the requirements in Appendix C of [I-D.ietf-ace-oauth-authz].
1.1. Terminology
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.
Readers are expected to be familiar with the terms and concepts from
the following specifications:
o CBOR [I-D.ietf-cbor-7049bis] and COSE
[I-D.ietf-cose-rfc8152bis-struct][I-D.ietf-cose-rfc8152bis-algs].
o The CoAP protocol [RFC7252], also in group communication scenarios
[I-D.ietf-core-groupcomm-bis]. These include the concepts of:
* "application group", as a set of CoAP nodes that share a common
set of resources; and of
* "security group", as a set of CoAP nodes that share the same
security material, and use it to protect and verify exchanged
messages.
o The OSCORE [RFC8613] and Group OSCORE
[I-D.ietf-core-oscore-groupcomm] security protocols. These
include the concept of Group Manager, as the entity responsible
for a set of OSCORE groups where communications among members are
secured using Group OSCORE. An OSCORE group is used as security
group for one or many application groups.
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o The ACE framework for authentication and authorization
[I-D.ietf-ace-oauth-authz]. The terminology for entities in the
considered architecture is defined in OAuth 2.0 [RFC6749]. In
particular, this includes Client (C), Resource Server (RS), and
Authorization Server (AS).
o The management of keying material for groups in ACE
[I-D.ietf-ace-key-groupcomm] and specifically for OSCORE groups
[I-D.ietf-ace-key-groupcomm-oscore]. These include the concept of
group-membership resource hosted by the Group Manager, that new
members access to join the OSCORE group, while current members can
access to retrieve updated keying material.
Note that, unless otherwise indicated, the term "endpoint" is used
here following its OAuth definition, aimed at denoting resources such
as /token and /introspect at the AS, and /authz-info at the RS. This
document does not use the CoAP definition of "endpoint", which is "An
entity participating in the CoAP protocol".
This document also refers to the following terminology.
o Administrator: entity responsible to create, configure and delete
OSCORE groups at a Group Manager.
o Group name: stable and invariant name of an OSCORE group. The
group name MUST be unique under the same Group Manager, and MUST
include only characters that are valid for a URI path segment.
o Group-collection resource: a single-instance resource hosted by
the Group Manager. An Administrator accesses a group-collection
resource to create a new OSCORE group, or to retrieve the list of
existing OSCORE groups, under that Group Manager. As an example,
this document uses /manage as the url-path of the group-collection
resource; implementations are not required to use this name, and
can define their own instead.
o Group-configuration resource: a resource hosted by the Group
Manager, associated to an OSCORE group under that Group Manager.
A group-configuration resource is identifiable with the invariant
group name of the respective OSCORE group. An Administrator
accesses a group-configuration resource to retrieve or update the
configuration of the respective OSCORE group, or to delete that
group. The url-path to a group-configuration resource has
GROUPNAME as last segment, with GROUPNAME the invariant group name
assigned upon its creation. Building on the considered url-path
of the group-collection resource, this document uses /manage/
GROUPNAME as the url-path of a group-configuration resource;
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implementations are not required to use this name, and can define
their own instead.
o Admin endpoint: an endpoint at the Group Manager associated to the
group-collection resource or to a group-configuration resource
hosted by that Group Manager.
2. Group Administration
With reference to the ACE framework and the terminology defined in
OAuth 2.0 [RFC6749]:
o The Group Manager acts as Resource Server (RS). It provides one
single group-collection resource, and one group-configuration
resource per existing OSCORE group. Each of those is exported by
a distinct admin endpoint.
o The Administrator acts as Client (C), and requests to access the
group-collection resource and group-configuration resources, by
accessing the respective admin endpoint at the Group Manager.
o The Authorization Server (AS) authorizes the Administrator to
access the group-collection resource and group-configuration
resources at a Group Manager. Multiple Group Managers can be
associated to the same AS. The AS MAY release Access Tokens to
the Administrator for other purposes than accessing admin
endpoints of registered Group Managers.
2.1. Getting Access to the Group Manager
All communications between the involved entities rely on the CoAP
protocol and MUST be secured.
In particular, communications between the Administrator and the Group
Manager leverage protocol-specific transport profiles of ACE to
achieve communication security, proof-of-possession and server
authentication. To this end, the AS may explicitly signal the
specific transport profile to use, consistently with requirements and
assumptions defined in the ACE framework [I-D.ietf-ace-oauth-authz].
With reference to the AS, communications between the Administrator
and the AS (/token endpoint) as well as between the Group Manager and
the AS (/introspect endpoint) can be secured by different means, for
instance using DTLS [RFC6347][I-D.ietf-tls-dtls13] or OSCORE
[RFC8613]. Further details on how the AS secures communications
(with the Administrator and the Group Manager) depend on the
specifically used transport profile of ACE, and are out of the scope
of this specification.
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In order to get access to the Group Manager for managing OSCORE
groups, an Administrator performs the following steps.
1. The Administrator requests an Access Token from the AS, in order
to access the group-collection and group-configuration resources
on the Group Manager. The Administrator will start or continue
using secure communications with the Group Manager, according to
the response from the AS.
2. The Administrator transfers authentication and authorization
information to the Group Manager by posting the obtained Access
Token, according to the used profile of ACE, such as
[I-D.ietf-ace-dtls-authorize] and [I-D.ietf-ace-oscore-profile].
After that, the Administrator must have secure communication
established with the Group Manager, before performing any admin
operation on that Group Manager. Possible ways to provide secure
communication are DTLS [RFC6347][I-D.ietf-tls-dtls13] and OSCORE
[RFC8613]. The Administrator and the Group Manager maintain the
secure association, to support possible future communications.
3. The Administrator performs admin operations at the Group Manager,
as described in the following sections. These include the
retrieval of the existing OSCORE groups, the creation of new
OSCORE groups, the update and retrieval of OSCORE group
configurations, and the removal of OSCORE groups. Messages
exchanged among the Administrator and the Group Manager are
specified in Section 4.
2.2. Managing OSCORE Groups
Figure 1 shows the resources of a Group Manager available to an
Administrator.
___
Group / \
Collection \___/
\
\____________________
\___ \___ \___
/ \ / \ ... / \ Group
\___/ \___/ \___/ Configurations
Figure 1: Resources of a Group Manager
The Group Manager exports a single group-collection resource, with
resource type "core.osc.gcoll" defined in Section 6.2 of this
specification. The interface for the group-collection resource
defined in Section 4 allows the Administrator to:
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o Retrieve the complete list of existing OSCORE groups.
o Retrieve a partial list of existing OSCORE groups, by applying
filter criteria.
o Create a new OSCORE group, specifying its invariant group name
and, optionally, its configuration.
The Group Manager exports one group-configuration resource for each
of its OSCORE groups. Each group-configuration resource has resource
type "core.osc.gconf" defined in Section 6.2 of this specification,
and is identified by the group name specified upon creating the
OSCORE group. The interface for a group-configuration resource
defined in Section 4 allows the Administrator to:
o Retrieve the complete current configuration of the OSCORE group.
o Retrieve part of the current configuration of the OSCORE group, by
applying filter criteria.
o Overwrite the current configuration of the OSCORE group.
o Delete the OSCORE group.
2.3. Collection Representation
A list of group configurations is represented as a document
containing the corresponding group-configuration resources in the
list. Each group-configuration is represented as a link, where the
link target is the URI of the group-configuration resource.
The list can be represented as a Link Format document [RFC6690] or a
CoRAL document [I-D.ietf-core-coral].
In the former case, the link to each group-configuration resource
specifies the link target attribute 'rt' (Resource Type), with value
"core.osc.gconf" defined in Section 6.2 of this specification.
In the latter case, the CoRAL document specifies the group-
configuration resources in the list as top-level elements. In
particular, the link to each group-configuration resource has
http://coreapps.org/core.osc.gcoll#item as relation type.
2.4. Discovery
The Administrator can discover the group-collection resource from a
Resource Directory, for instance [I-D.ietf-core-resource-directory]
and [I-D.hartke-t2trg-coral-reef], or from .well-known/core, by using
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the resource type "core.osc.gcoll" defined in Section 6.2 of this
specification.
The Administrator can discover group-configuration resources for the
group-collection resource as specified in Section 4.1 and
Section 4.2.
3. Group Configurations
A group configuration consists of a set of parameters.
3.1. Group Configuration Representation
The group configuration representation is a CBOR map which MUST
include configuration properties and status properties.
3.1.1. Configuration Properties
The CBOR map MUST include the following configuration parameters:
o 'hkdf', defined in Section 6.1 of this document, specifies the
HKDF algorithm used in the OSCORE group, encoded as a CBOR text
string or a CBOR integer. Possible values are the same ones
admitted for the 'hkdf' parameter of the "OSCORE Security Context
Parameters" registry, defined in Section 3.2.1 of
[I-D.ietf-ace-oscore-profile].
o 'alg', defined in Section 6.1 of this document, specifies the AEAD
algorithm used in the OSCORE group, encoded as a CBOR text string
or a CBOR integer. Possible values are the same ones admitted for
the 'alg' parameter of the "OSCORE Security Context Parameters"
registry, defined in Section 3.2.1 of
[I-D.ietf-ace-oscore-profile].
o 'cs_alg', defined in Section 6.1 of this document, specifies the
countersignature algorithm used in the OSCORE group, encoded as a
CBOR text string or a CBOR integer. Possible values are the same
ones admitted for the 'cs_alg' parameter of the "OSCORE Security
Context Parameters" registry, defined in Section 6.4 of
[I-D.ietf-ace-key-groupcomm-oscore].
o 'cs_params', defined in Section 6.1 of this document, specifies
the additional parameters for the countersignature algorithm used
in the OSCORE group, encoded as a CBOR array. Possible formats
and values are the same ones admitted for the 'cs_params'
parameter of the "OSCORE Security Context Parameters" registry,
defined in Section 6.4 of [I-D.ietf-ace-key-groupcomm-oscore].
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o 'cs_key_params', defined in Section 6.1 of this document,
specifies the additional parameters for the key used with the
countersignature algorithm in the OSCORE group, encoded as a CBOR
array. Possible formats and values are the same ones admitted for
the 'cs_key_params' parameter of the "OSCORE Security Context
Parameters" registry, defined in Section 6.4 of
[I-D.ietf-ace-key-groupcomm-oscore].
o 'cs_key_enc', defined in Section 6.1 of this document, specifies
the encoding of the public keys of group members, encoded as a
CBOR integer. Possible values are the same ones admitted for the
'cs_key_enc' parameter of the "OSCORE Security Context Parameters"
registry, defined in Section 6.4 of
[I-D.ietf-ace-key-groupcomm-oscore].
o 'pairwise_mode', defined in Section 6.1 of this document and
encoded as a CBOR simple value. Its value is True if the OSCORE
group supports the pairwise mode of Group OSCORE
[I-D.ietf-core-oscore-groupcomm], or False otherwise.
o 'ecdh_alg', defined in Section 6.1 of this document and formatted
as follows. If the configuration parameter 'pairwise_mode' has
value False, this parameter has as value the CBOR simple value
Null. Otherwise, this parameter specifies the ECDH algorithm used
in the OSCORE group, encoded as a CBOR text string or a CBOR
integer. Possible values are the same ones admitted for the
'ecdh_alg' parameter of the "OSCORE Security Context Parameters"
registry, defined in Section 6.4 of
[I-D.ietf-ace-key-groupcomm-oscore].
o 'ecdh_params', defined in Section 6.1 of this document and
formatted as follows. If the configuration parameter
'pairwise_mode' has value False, this parameter has as value the
CBOR simple value Null. Otherwise, this parameter specifies the
parameters for the ECDH algorithm used in the OSCORE group,
encoded as a CBOR array. Possible formats and values are the same
ones admitted for the 'ecdh_params' parameter of the "OSCORE
Security Context Parameters" registry, defined in Section 6.4 of
[I-D.ietf-ace-key-groupcomm-oscore].
o 'ecdh_key_params', defined in Section 6.1 of this document and
formatted as follows. If the configuration parameter
'pairwise_mode' has value False, this parameter has as value the
CBOR simple value Null. Otherwise, this parameter specifies the
additional parameters for the key used with the ECDH algorithm in
the OSCORE group, encoded as a CBOR array. Possible formats and
values are the same ones admitted for the 'ecdh_key_params'
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parameter of the "OSCORE Security Context Parameters" registry,
defined in Section 6.4 of [I-D.ietf-ace-key-groupcomm-oscore].
3.1.2. Status Properties
The CBOR map MUST include the following status parameters:
o 'rt', with value the resource type "core.osc.gconf" associated to
group-configuration resources, encoded as a CBOR text string.
o 'active', encoding the CBOR simple value True if the OSCORE group
is currently active, or the CBOR simple value False otherwise.
This parameter is defined in Section 6.1 of this specification.
o 'group_name', with value the group name of the OSCORE group
encoded as a CBOR text string. This parameter is defined in
Section 6.1 of this specification.
o 'group_title', with value either a human-readable description of
the OSCORE group encoded as a CBOR text string, or the CBOR simple
value Null if no description is specified. This parameter is
defined in Section 6.1 of this specification.
o 'ace-groupcomm-profile', defined in Section 4.1.2.1 of
[I-D.ietf-ace-key-groupcomm], with value "coap_group_oscore_app"
defined in Section 21.3 of [I-D.ietf-ace-key-groupcomm-oscore]
encoded as a CBOR integer.
o 'exp', defined in Section 4.1.2.1 of [I-D.ietf-ace-key-groupcomm].
o 'app_groups', with value a list of names of application groups,
encoded as a CBOR array. Each element of the array is a CBOR text
string, specifying the name of an application group using the
OSCORE group as security group (see Section 2.1 of
[I-D.ietf-core-groupcomm-bis]).
o 'joining_uri', with value the URI of the group-membership resource
for joining the newly created OSCORE group as per Section 6.2 of
[I-D.ietf-ace-key-groupcomm-oscore], encoded as a CBOR text
string. This parameter is defined in Section 6.1 of this
specification.
The CBOR map MAY include the following status parameters:
o 'group_policies', defined in Section 4.1.2.1 of
[I-D.ietf-ace-key-groupcomm], and consistent with the format and
content defined in Section 6.4 of
[I-D.ietf-ace-key-groupcomm-oscore].
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o 'as_uri', defined in Section 6.1 of this document, specifies the
URI of the Authorization Server associated to the Group Manager
for the OSCORE group, encoded as a CBOR text string. Candidate
group members will have to obtain an Access Token from that
Authorization Server, before starting the joining process with the
Group Manager to join the OSCORE group (see Section 4 and
Section 6 of [I-D.ietf-ace-key-groupcomm-oscore]).
3.2. Default Values
This section defines the default values that the Group Manager
assumes for configuration and status parameters.
3.2.1. Configuration Parameters
For each configuration parameter, the Group Manager MUST use a pre-
configured default value, if none is specified by the Administrator.
In particular:
o For 'pairwise_mode', the Group Manager SHOULD use the CBOR simple
value False.
o If 'pairwise_mode' has value True, the Group Manager SHOULD use
the same default values defined in Section 19 of
[I-D.ietf-ace-key-groupcomm-oscore] for the parameters 'ecdh_alg',
'ecdh_params' and 'ecdh_key_params'.
o For any other configuration parameter, the Group Manager SHOULD
use the same default values defined in Section 19 of
[I-D.ietf-ace-key-groupcomm-oscore].
3.2.2. Status Parameters
For the following status parameters, the Group Manager MUST use a
pre-configured default value, if none is specified by the
Administrator. In particular:
o For 'active', the Group Manager SHOULD use the CBOR simple value
False.
o For 'group_title', the Group Manager SHOULD use the CBOR simple
value Null.
o For 'app_groups', the Group Manager SHOULD use the empty CBOR
array.
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4. Interactions with the Group Manager
This section describes the operations available on the group-
collection resource and the group-configuration resources.
When custom CBOR is used, the Content-Format in messages containing a
payload is set to application/ace-groupcomm+cbor, defined in
Section 8.2 of [I-D.ietf-ace-key-groupcomm]. Furthermore, the entry
labels defined in Section 6.1 of this document MUST be used, when
specifying the corresponding configuration and status parameters.
4.1. Retrieve the Full List of Groups Configurations
The Administrator can send a GET request to the group-collection
resource, in order to retrieve the complete list of the existing
OSCORE groups at the Group Manager. This is returned as a list of
links to the corresponding group-configuration resources.
Example in Link Format:
=> 0.01 GET
Uri-Path: manage
<= 2.05 Content
Content-Format: 40 (application/link-format)
<coap://[2001:db8::ab]/manage/gp1>;rt="core.osc.gconf",
<coap://[2001:db8::ab]/manage/gp2>;rt="core.osc.gconf",
<coap://[2001:db8::ab]/manage/gp3>;rt="core.osc.gconf"
Example in CoRAL:
=> 0.01 GET
Uri-Path: manage
<= 2.05 Content
Content-Format: TBD1 (application/coral+cbor)
#using <http://coreapps.org/core.osc.gcoll#>
#base </manage/>
item <gp1>
item <gp2>
item <gp3>
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4.2. Retrieve a List of Group Configurations by Filters
The Administrator can send a FETCH request to the group-collection
resource, in order to retrieve the list of the existing OSCORE groups
that fully match a set of specified filter criteria. This is
returned as a list of links to the corresponding group-configuration
resources.
When custom CBOR is used, the set of filter criteria is specified in
the request payload as a CBOR map, whose possible entries are
specified in Section 3.1 and use the same abbreviations defined in
Section 6.1. Entry values are the ones admitted for the
corresponding labels in the POST request for creating a group
configuration (see Section 4.3). A valid request MUST NOT include
the same entry multiple times.
When CoRAL is used, the filter criteria are specified in the request
payload with top-level elements, each of which corresponds to an
entry specified in Section 3.1, with the exception of the 'app_names'
status parameter. If names of application groups are used as filter
criteria, each element of the 'app_groups' array from the status
properties is included as a separate element with name 'app_group'.
With the exception of the 'app_group' element, a valid request MUST
NOT include the same element multiple times. Element values are the
ones admitted for the corresponding labels in the POST request for
creating a group configuration (see Section 4.3).
Example in custom CBOR and Link Format:
=> 0.05 FETCH
Uri-Path: manage
Content-Format: TBD2 (application/ace-groupcomm+cbor)
{
"alg" : 10,
"hkdf" : 5
}
<= 2.05 Content
Content-Format: 40 (application/link-format)
<coap://[2001:db8::ab]/manage/gp1>;rt="core.osc.gconf",
<coap://[2001:db8::ab]/manage/gp2>;rt="core.osc.gconf",
<coap://[2001:db8::ab]/manage/gp3>;rt="core.osc.gconf"
Example in CoRAL:
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=> 0.05 FETCH
Uri-Path: manage
Content-Format: TBD1 (application/coral+cbor)
alg 10
hkdf 5
<= 2.05 Content
Content-Format: TBD1 (application/coral+cbor)
#using <http://coreapps.org/core.osc.gcoll#>
#base </manage/>
item <gp1>
item <gp2>
item <gp3>
4.3. Create a New Group Configuration
The Administrator can send a POST request to the group-collection
resource, in order to create a new OSCORE group at the Group Manager.
The request MAY specify the intended group name GROUPNAME and group
title, and MAY specify pieces of information concerning the group
configuration.
When custom CBOR is used, the request payload is a CBOR map, whose
possible entries are specified in Section 3.1 and use the same
abbreviations defined in Section 6.1.
When CoRAL is used, each element of the request payload corresponds
to an entry specified in Section 3.1, with the exception of the
'app_names' status parameter (see below).
In particular:
o The payload MAY include any of the configuration parameter defined
in Section 3.1.1.
o The payload MAY include any of the status parameter 'group_name',
'group_title', 'exp', 'app_groups, 'group_policies', 'as_uri' and
'active' defined in Section 3.1.2.
* When CoRAL is used, each element of the 'app_groups' array from
the status properties is included as a separate element with
name 'app_group'.
o The payload MUST NOT include any of the status parameter 'rt',
'ace-groupcomm-profile' and 'joining_uri' defined in
Section 3.1.2.
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If any of the following occurs, the Group Manager MUST respond with a
4.00 (Bad Request) response, which MAY include additional information
to clarify what went wrong.
o Any of the received parameters is specified multiple times, with
the exception of the 'app_group' element when using CoRAL.
o Any of the received parameters is not recognized, or not valid, or
not consistent with respect to other related parameters.
o The 'group_name' parameter specifies the group name of an already
existing OSCORE group.
o The Group Manager does not trust the Authorization Server with URI
specified in the 'as_uri' parameter, and has no alternative
Authorization Server to consider for the OSCORE group to create.
After a successful processing of the request above, the Group Manager
performs the following actions.
First, the Group Manager creates a new group-configuration resource,
accessible to the Administrator at /manage/GROUPNAME, where GROUPNAME
is the name of the OSCORE group as either indicated in the parameter
'group_name' of the request or uniquely assigned by the Group
Manager. Note that the final decision about the name assigned to the
OSCORE group is of the Group Manager, which may have more constraints
than the Administrator can be aware of, possibly beyond the
availability of suggested names.
The value of the status parameter 'rt' is set to "core.osc.gconf".
The values of other parameters specified in the request are used as
group configuration information for the newly created OSCORE group.
For each configuration parameter not specified in the request, the
Group Manager MUST use default values as specified in Section 3.2.
After that, the Group Manager creates a new group-membership resource
accessible at ace-group/GROUPNAME to nodes that want to join the
OSCORE group, as specified in Section 6.2 of
[I-D.ietf-ace-key-groupcomm-oscore]. Note that such group
membership-resource comprises a number of sub-resources intended to
current group members, as defined in Section 4.1 of
[I-D.ietf-ace-key-groupcomm] and Section 5 of
[I-D.ietf-ace-key-groupcomm-oscore].
From then on, the Group Manager will rely on the current group
configuration to build the Joining Response message defined in
Section 6.4 of [I-D.ietf-ace-key-groupcomm-oscore], when handling the
joining of a new group member. Furthermore, the Group Manager
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generates the following pieces of information, and assigns them to
the newly created OSCORE group.
o The OSCORE Master Secret.
o The OSCORE Master Salt (optionally).
o The Group ID, used as OSCORE ID Context, which MUST be unique
within the set of OSCORE groups under the Group Manager.
Finally, the Group Manager replies to the Administrator with a 2.01
(Created) response. The Location-Path option MUST be included in the
response, indicating the location of the just created group-
configuration resource. The response MUST NOT include a Location-
Query option.
The response payload specifies the parameters 'group_name',
'joining_uri' and 'as_uri', from the status properties of the newly
created OSCORE group (see Section 3.1), as detailed below.
When custom CBOR is used, the response payload is a CBOR map, where
entries use the same abbreviations defined in Section 6.1. When
CoRAL is used, the response payload includes one element for each
specified parameter.
o 'group_name', with value the group name of the OSCORE group. This
value can be different from the group name possibly specified by
the Administrator in the POST request, and reflects the final
choice of the Group Manager as 'group_name' status property for
the OSCORE group. This parameter MUST be included.
o 'joining_uri', with value the URI of the group-membership resource
for joining the newly created OSCORE group. This parameter MUST
be included.
o 'as_uri', with value the URI of the Authorization Server
associated to the Group Manager for the newly created OSCORE
group. This parameter MUST be included if specified in the status
properties of the group. This value can be different from the URI
possibly specified by the Administrator in the POST request, and
reflects the final choice of the Group Manager as 'as_uri' status
property for the OSCORE group.
The Group Manager can register the link to the group-membership
resource with URI specified in 'joining_uri' to a Resource Directory
[I-D.ietf-core-resource-directory][I-D.hartke-t2trg-coral-reef], as
defined in Section 2 of [I-D.tiloca-core-oscore-discovery]. The
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Group Manager considers the current group configuration when
specifying additional information for the link to register.
Alternatively, the Administrator can perform the registration in the
Resource Directory on behalf of the Group Manager, acting as
Commissioning Tool. The Administrator considers the following when
specifying additional information for the link to register.
o The name of the OSCORE group MUST take the value specified in
'group_name' from the 2.01 (Created) response above.
o The names of the application groups using the OSCORE group MUST
take the values possibly specified by the elements of the
'app_groups' parameter (when custom CBOR is used) or by the
different 'app_group' elements (when CoRAL is used) in the POST
request above.
o If present, parameters describing the cryptographic algorithms
used in the OSCORE group MUST follow the values that the
Administrator specified in the POST request above, or the
corresponding default values specified in Section 3.2.1 otherwise.
o If also registering a related link to the Authorization Server
associated to the OSCORE group, the related link MUST have as link
target the URI in 'as_uri' from the 2.01 (Created) response above,
if the 'as_uri' parameter was included in the response.
Note that, compared to the Group Manager, the Administrator is less
likely to remain closely aligned with possible changes and updates
that would require a prompt update to the registration in the
Resource Directory. This applies especially to the address of the
Group Manager, as well as the URI of the group-membership resource or
of the Authorization Server associated to the Group Manager.
Therefore, it is RECOMMENDED that registrations of links to group-
membership resources in the Resource Directory are made (and possibly
updated) directly by the Group Manager, rather than by the
Administrator.
Example in custom CBOR:
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=> 0.02 POST
Uri-Path: manage
Content-Format: TBD2 (application/ace-groupcomm+cbor)
{
"alg" : 10,
"hkdf" : 5,
"pairwise_mode" : True,
"active" : True,
"group_title" : "rooms 1 and 2",
"app_groups": : ["room1", "room2"],
"as_uri" : "coap://as.example.com/token"
}
<= 2.01 Created
Location-Path: manage
Location-Path: gp4
Content-Format: TBD2 (application/ace-groupcomm+cbor)
{
"group_name" : "gp4",
"joining_uri" : "coap://[2001:db8::ab]/ace-group/gp4/",
"as_uri" : "coap://as.example.com/token"
}
Example in CoRAL:
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=> 0.02 POST
Uri-Path: manage
Content-Format: TBD1 (application/coral+cbor)
#using <http://coreapps.org/core.osc.gconf#>
alg 10
hkdf 5
pairwise_mode True
active True
group_title "rooms 1 and 2"
app_group "room1"
app_group "room2"
as_uri <coap://as.example.com/token>
<= 2.01 Created
Location-Path: manage
Location-Path: gp4
Content-Format: TBD1 (application/coral+cbor)
#using <http://coreapps.org/core.osc.gconf#>
group_name "gp4"
joining_uri <coap://[2001:db8::ab]/ace-group/gp4/>
as_uri <coap://as.example.com/token>
4.4. Retrieve a Group Configuration
The Administrator can send a GET request to the group-configuration
resource manage/GROUPNAME associated to an OSCORE group with group
name GROUPNAME, in order to retrieve the complete current
configuration of that group.
After a successful processing of the request above, the Group Manager
replies to the Administrator with a 2.05 (Content) response. The
response has as payload the representation of the group configuration
as specified in Section 3.1. The exact content of the payload
reflects the current configuration of the OSCORE group. This
includes both configuration properties and status properties.
When custom CBOR is used, the response payload is a CBOR map, whose
possible entries are specified in Section 3.1 and use the same
abbreviations defined in Section 6.1.
When CoRAL is used, the response payload includes one element for
each entry specified in Section 3.1, with the exception of the
'app_names' status parameter. That is, each element of the
'app_groups' array from the status properties is included as a
separate element with name 'app_group'.
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Example in custom CBOR:
=> 0.01 GET
Uri-Path: manage
Uri-Path: gp4
<= 2.05 Content
Content-Format: TBD2 (application/ace-groupcomm+cbor)
{
"alg" : 10,
"hkdf" : 5,
"cs_alg" : -8,
"cs_params" : [[1], [1, 6]],
"cs_key_params" : [1, 6],
"cs_key_enc" : 1,
"pairwise_mode" : True,
"ecdh_alg" : -27,
"ecdh_params" : [[1], [1, 6]],
"ecdh_key_params" : [1, 6],
"rt" : "core.osc.gconf",
"active" : True,
"group_name" : "gp4",
"group_title" : "rooms 1 and 2",
"ace-groupcomm-profile" : "coap_group_oscore_app",
"exp" : "1360289224",
"app_groups": : ["room1", "room2"],
"joining_uri" : "coap://[2001:db8::ab]/ace-group/gp4/",
"as_uri" : "coap://as.example.com/token"
}
Example in CoRAL:
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=> 0.01 GET
Uri-Path: manage
Uri-Path: gp4
<= 2.05 Content
Content-Format: TBD1 (application/coral+cbor)
#using <http://coreapps.org/core.osc.gconf#>
alg 10
hkdf 5
cs_alg -8
cs_params.alg_capab.key_type 1
cs_params.key_type_capab.key_type 1
cs_params.key_type_capab.curve 6
cs_key_params.key_type 1
cs_key_params.curve 6
cs_key_enc 1
pairwise_mode True
ecdh_alg -27
ecdh_params.alg_capab.key_type 1
ecdh_params.key_type_capab.key_type 1
ecdh_params.key_type_capab.curve 6
ecdh_key_params.key_type 1
ecdh_key_params.curve 6
rt "core.osc.gconf",
active True
group_name "gp4"
group_title "rooms 1 and 2"
ace-groupcomm-profile "coap_group_oscore_app"
exp "1360289224"
app_group "room1"
app_group "room2"
joining_uri <coap://[2001:db8::ab]/ace-group/gp4/>
as_uri <coap://as.example.com/token>
4.5. Retrieve Part of a Group Configuration by Filters
The Administrator can send a FETCH request to the group-configuration
resource manage/GROUPNAME associated to an OSCORE group with group
name GROUPNAME, in order to retrieve part of the current
configuration of that group.
When custom CBOR is used, the request payload is a CBOR map, which
contains the following fields:
o 'conf_filter', defined in Section 6.1 of this document and encoded
as a CBOR array. Each element of the array specifies one
requested configuration parameter or status parameter of the
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current group configuration (see Section 3.1), using the
corresponding abbreviation defined in Section 6.1.
When CoRAL is used, the request payload includes one element for each
requested configuration parameter or status parameter of the current
group configuration (see Section 3.1). All the specified elements
have no value.
After a successful processing of the request above, the Group Manager
replies to the Administrator with a 2.05 (Content) response. The
response has as payload a partial representation of the group
configuration (see Section 3.1). The exact content of the payload
reflects the current configuration of the OSCORE group, and is
limited to the configuration properties and status properties
requested by the Administrator in the FETCH request.
The response payload includes the requested configuration parameters
and status parameters, and is formatted as in the response payload of
a GET request to a group-configuration resource (see Section 4.4).
Example in custom CBOR:
=> 0.05 FETCH
Uri-Path: manage
Uri-Path: gp4
Content-Format: TBD2 (application/ace-groupcomm+cbor)
{
"conf_filter" : ["alg",
"hkdf",
"pairwise_mode",
"active",
"group_title",
"app_groups"]
}
<= 2.05 Content
Content-Format: TBD2 (application/ace-groupcomm+cbor)
{
"alg" : 10,
"hkdf" : 5,
"pairwise_mode" : True,
"active" : True,
"group_title" : "rooms 1 and 2",
"app_groups": : ["room1", "room2"]
}
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Example in CoRAL:
=> 0.05 FETCH
Uri-Path: manage
Uri-Path: gp4
Content-Format: TBD1 (application/coral+cbor)
#using <http://coreapps.org/core.osc.gconf#>
alg
hkdf
pairwise_mode
active
group_title
app_groups
<= 2.05 Content
Content-Format: TBD1 (application/coral+cbor)
#using <http://coreapps.org/core.osc.gconf#>
alg 10
hkdf 5
pairwise_mode True
active True
group_title "rooms 1 and 2"
app_group "room1"
app_group "room2"
4.6. Overwrite a Group Configuration
The Administrator can send a PUT request to the group-configuration
resource associated to an OSCORE group, in order to overwrite the
current configuration of that group with a new one. The payload of
the request has the same format of the POST request defined in
Section 4.3, with the exception of the status parameter 'group_name'
that MUST NOT be included.
The error handling for the PUT request is the same as for the POST
request defined in Section 4.3. If no error occurs, the Group
Manager performs the following actions.
First, the Group Manager updates the configuration of the OSCORE
group, consistently with the values indicated in the PUT request from
the Administrator. For each parameter not specified in the PUT
request, the Group Manager MUST use the default value as specified in
Section 3.2. From then on, the Group Manager relies on the latest
updated configuration to build the Joining Response message defined
in Section 6.4 of [I-D.ietf-ace-key-groupcomm-oscore], when handling
the joining of a new group member.
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Then, the Group Manager replies to the Administrator with a 2.04
(Changed) response. The payload of the response has the same format
of the 2.01 (Created) response defined in Section 4.3.
If the link to the group-membership resource was registered in the
Resource Directory (see [I-D.ietf-core-resource-directory]), the GM
is responsible to refresh the registration, as defined in Section 3
of [I-D.tiloca-core-oscore-discovery].
Alternatively, the Administrator can update the registration in the
Resource Directory on behalf of the Group Manager, acting as
Commissioning Tool. The Administrator considers the following when
specifying additional information for the link to update.
o The name of the OSCORE group MUST take the value specified in
'group_name' from the 2.04 (Changed) response above.
o The names of the application groups using the OSCORE group MUST
take the values possibly specified by the elements of the
'app_groups' parameter (when custom CBOR is used) or by the
different 'app_group' elements (when CoRAL is used) in the PUT
request above.
o If present, parameters describing the cryptographic algorithms
used in the OSCORE group MUST follow the values that the
Administrator specified in the PUT request above, or the
corresponding default values as specified in Section 3.2.1
otherwise.
o If also registering a related link to the Authorization Server
associated to the OSCORE group, the related link MUST have as link
target the URI in 'as_uri' from the 2.04 (Changed) response above,
if the 'as_uri' parameter was included in the response.
As discussed in Section 4.3, it is RECOMMENDED that registrations of
links to group-membership resources in the Resource Directory are
made (and possibly updated) directly by the Group Manager, rather
than by the Administrator.
Example in custom CBOR:
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=> PUT
Uri-Path: manage
Uri-Path: gp4
Content-Format: TBD2 (application/ace-groupcomm+cbor)
{
"alg" : 11 ,
"hkdf" : 5
}
<= 2.04 Changed
Content-Format: TBD2 (application/ace-groupcomm+cbor)
{
"group_name" : "gp4",
"joining_uri" : "coap://[2001:db8::ab]/ace-group/gp4/",
"as_uri" : "coap://as.example.com/token"
}
Example in CoRAL:
=> PUT
Uri-Path: manage
Uri-Path: gp4
Content-Format: TBD1 (application/coral+cbor)
#using <http://coreapps.org/core.osc.gconf#>
alg 11
hkdf 5
<= 2.04 Changed
Content-Format: TBD1 (application/coral+cbor)
#using <http://coreapps.org/core.osc.gconf#>
group_name "gp4"
joining_uri <coap://[2001:db8::ab]/ace-group/gp4/>
as_uri <coap://as.example.com/token>
4.6.1. Effects on Joining Nodes
If the value of the status parameter 'active' is changed from True to
False, the Group Manager MUST stop admitting new members in the
OSCORE group. In particular, upon receiving a Joining Request (see
Section 6.3 of [I-D.ietf-ace-key-groupcomm-oscore]), the Group
Manager MUST respond with a 5.03 (Service Unavailable) response to
the joining node, and MAY include additional information to clarify
what went wrong.
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If the value of the status parameter 'active' is changed from False
to True, the Group Manager resumes admitting new members in the
OSCORE group, by processing their Joining Requests (see Section 6.3
of [I-D.ietf-ace-key-groupcomm-oscore]).
4.6.2. Effects on the Group Members
After having updated a group configuration, the Group Manager informs
the members of the OSCORE group, over the pairwise secure
communication channels established when joining the group (see
Section 6 of [I-D.ietf-ace-key-groupcomm-oscore]).
To this end, the Group Manager can individually target the
'control_path' URI of each group member (see Section 4.1.2.1 of
[I-D.ietf-ace-key-groupcomm]), if provided by the intended recipient
upon joining the OSCORE group (see Section 6.2 of
[I-D.ietf-ace-key-groupcomm-oscore]). Alternatively, group members
can subscribe for updates to the group-membership resource of the
OSCORE group, e.g. by using CoAP Observe [RFC7641].
Every group member, upon learning that the OSCORE group has been
deactivated (i.e. 'active' has value False), SHOULD stop
communicating in the group.
Every group member, upon learning that the OSCORE group has been
reactivated (i.e. 'active' has value True again), can resume
communicating in the group.
Every group member, upon learning that the OSCORE group has stopped
supporting the pairwise mode of Group OSCORE (i.e. 'pairwise_mode'
has value False), SHOULD stop using the pairwise mode to process
messages in the group.
Every group member, upon learning that the OSCORE group has resumed
supporting the pairwise mode of Group OSCORE (i.e. 'pairwise_mode'
has value True again), can resume using the pairwise mode to process
messages in the group.
Every group member, upon receiving updated values for 'alg' and
'hkdf', MUST either:
o Leave the OSCORE group (see Section 16 of
[I-D.ietf-ace-key-groupcomm-oscore]), e.g. if not supporting the
indicated new algorithms; or
o Use the new parameter values, and accordingly re-derive the OSCORE
Security Context for the OSCORE group (see Section 2 of
[I-D.ietf-core-oscore-groupcomm]).
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Every group member, upon receiving updated values for 'cs_alg',
'cs_params', 'cs_key_params', 'cs_key_enc', 'ecdh_alg', 'ecdh_params'
and 'ecdh_key_params' MUST either:
o Leave the OSCORE group, e.g. if not supporting the indicated new
algorithm, parameters and encoding; or
o Leave the OSCORE group and rejoin it (see Section 6 of
[I-D.ietf-ace-key-groupcomm-oscore]), providing the Group Manager
with a public key which is compatible with the indicated new
algorithm, parameters and encoding; or
o Use the new parameter values, and, if required, provide the Group
Manager with a new public key to use in the OSCORE group, as
compatible with the indicated parameters (see Section 11 of
[I-D.ietf-ace-key-groupcomm-oscore]).
4.7. Delete a Group Configuration
The Administrator can send a DELETE request to the group-
configuration resource, in order to delete that OSCORE group. The
deletion would be successful only on an inactive OSCORE group.
That is, the DELETE request actually yields a successful deletion of
the OSCORE group, only if the corresponding status parameter 'active'
has current value False. The Administrator can ensure that, by first
performing an update of the group-configuration resource associated
to the OSCORE group (see Section 4.6), and setting the corresponding
status parameter 'active' to False.
If, upon receiving the DELETE request, the current value of the
status parameter 'active' is True, the Group Manager MUST respond
with a 4.09 (Conflict) response, which MAY include additional
information to clarify what went wrong.
After a successful processing of the request above, the Group Manager
performs the following actions.
First, the Group Manager deletes the OSCORE group and deallocates
both the group-configuration resource as well as the group-membership
resource associated to that group.
Then, the Group Manager replies to the Administrator with a 2.02
(Deleted) response.
Example:
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=> DELETE
Uri-Path: manage
Uri-Path: gp4
<= 2.02 Deleted
4.7.1. Effects on the Group Members
After having deleted an OSCORE group, the Group Manager can inform
the group members by means of the following two methods. When
contacting a group member, the Group Manager uses the pairwise secure
communication association established with that member during its
joining process (see Section 6 of
[I-D.ietf-ace-key-groupcomm-oscore]).
o The Group Manager sends an individual request message to each
group member, targeting the respective resource used to perform
the group rekeying process (see Section 18 of
[I-D.ietf-ace-key-groupcomm-oscore]). The Group Manager uses the
same format of the Joining Response message in Section 6.4 of
[I-D.ietf-ace-key-groupcomm-oscore], where only the parameters
'gkty', 'key', and 'ace-groupcomm-profile' are present, and the
'key' parameter is empty.
o A group member may subscribe for updates to the group-membership
resource associated to the OSCORE group. In particular, if this
relies on CoAP Observe [RFC7641], a group member would receive a
4.04 (Not Found) notification response from the Group Manager,
since the group-configuration resource has been deallocated upon
deleting the OSCORE group.
When being informed about the deletion of the OSCORE group, a group
member deletes the OSCORE Security Context that it stores as
associated to that group, and possibly deallocates any dedicated
control resource intended for the Group Manager that it has for that
group.
5. Security Considerations
Security considerations are inherited from the ACE framework for
Authentication and Authorization [I-D.ietf-ace-oauth-authz], and from
the specific transport profile of ACE used between the Administrator
and the Group Manager, such as [I-D.ietf-ace-dtls-authorize] and
[I-D.ietf-ace-oscore-profile].
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6. IANA Considerations
This document has the following actions for IANA.
6.1. ACE Groupcomm Parameters Registry
IANA is asked to register the following entries in the "ACE Groupcomm
Parameters" Registry defined in Section 8.5 of
[I-D.ietf-ace-key-groupcomm].
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+-----------------+----------+--------------+-------------------+
| Name | CBOR Key | CBOR Type | Reference |
+-----------------+----------+--------------+-------------------+
| | | | |
| hkdf | TBD | tstr / int | [[this document]] |
| | | | |
| alg | TBD | tstr / int | [[this document]] |
| | | | |
| cs_alg | TBD | tstr / int | [[this document]] |
| | | | |
| cs_params | TBD | array | [[this document]] |
| | | | |
| cs_key_params | TBD | array | [[this document]] |
| | | | |
| cs_key_enc | TBD | int | [[this document]] |
| | | | |
| pairwise_mode | TBD | simple value | [[this document]] |
| | | | |
| ecdh_alg | TBD | tstr / int / | [[this document]] |
| | | simple value | |
| | | | |
| ecdh_params | TBD | array / | [[this document]] |
| | | simple value | |
| | | | |
| ecdh_key_params | TBD | array / | [[this document]] |
| | | simple value | |
| | | | |
| active | TBD | simple value | [[this document]] |
| | | | |
| group_name | TBD | tstr | [[this document]] |
| | | | |
| group_title | TBD | tstr / | [[this document]] |
| | | simple value | |
| | | | |
| app_groups | TBD | array | [[this document]] |
| | | | |
| joining_uri | TBD | tstr | [[this document]] |
| | | | |
| as_uri | TBD | tstr | [[this document]] |
| | | | |
| conf_filter | TBD | array | [[this document]] |
| | | | |
+-----------------+----------+--------------+-------------------+
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6.2. Resource Types
IANA is asked to enter the following values into the Resource Type
(rt=) Link Target Attribute Values subregistry within the Constrained
Restful Environments (CoRE) Parameters registry defined in [RFC6690].
+----------------+------------------------------+-------------------+
| Value | Description | Reference |
+----------------+------------------------------+-------------------+
| | | |
| core.osc.gcoll | Group-collection resource | [[this document]] |
| | of an OSCORE Group Manager | |
| | | |
| core.osc.gconf | Group-configuration resource | [[this document]] |
| | of an OSCORE Group Manager | |
| | | |
+----------------+------------------------------+-------------------+
7. References
7.1. Normative References
[COSE.Algorithms]
IANA, "COSE Algorithms",
<https://www.iana.org/assignments/cose/
cose.xhtml#algorithms>.
[COSE.Elliptic.Curves]
IANA, "COSE Elliptic Curves",
<https://www.iana.org/assignments/cose/
cose.xhtml#elliptic-curves>.
[COSE.Key.Types]
IANA, "COSE Key Types",
<https://www.iana.org/assignments/cose/cose.xhtml#key-
type>.
[I-D.ietf-ace-key-groupcomm]
Palombini, F. and M. Tiloca, "Key Provisioning for Group
Communication using ACE", draft-ietf-ace-key-groupcomm-10
(work in progress), November 2020.
[I-D.ietf-ace-key-groupcomm-oscore]
Tiloca, M., Park, J., and F. Palombini, "Key Management
for OSCORE Groups in ACE", draft-ietf-ace-key-groupcomm-
oscore-09 (work in progress), November 2020.
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[I-D.ietf-ace-oauth-authz]
Seitz, L., Selander, G., Wahlstroem, E., Erdtman, S., and
H. Tschofenig, "Authentication and Authorization for
Constrained Environments (ACE) using the OAuth 2.0
Framework (ACE-OAuth)", draft-ietf-ace-oauth-authz-35
(work in progress), June 2020.
[I-D.ietf-ace-oscore-profile]
Palombini, F., Seitz, L., Selander, G., and M. Gunnarsson,
"OSCORE Profile of the Authentication and Authorization
for Constrained Environments Framework", draft-ietf-ace-
oscore-profile-13 (work in progress), October 2020.
[I-D.ietf-cbor-7049bis]
Bormann, C. and P. Hoffman, "Concise Binary Object
Representation (CBOR)", draft-ietf-cbor-7049bis-16 (work
in progress), September 2020.
[I-D.ietf-core-coral]
Hartke, K., "The Constrained RESTful Application Language
(CoRAL)", draft-ietf-core-coral-03 (work in progress),
March 2020.
[I-D.ietf-core-groupcomm-bis]
Dijk, E., Wang, C., and M. Tiloca, "Group Communication
for the Constrained Application Protocol (CoAP)", draft-
ietf-core-groupcomm-bis-02 (work in progress), November
2020.
[I-D.ietf-core-oscore-groupcomm]
Tiloca, M., Selander, G., Palombini, F., and J. Park,
"Group OSCORE - Secure Group Communication for CoAP",
draft-ietf-core-oscore-groupcomm-10 (work in progress),
November 2020.
[I-D.ietf-cose-rfc8152bis-algs]
Schaad, J., "CBOR Object Signing and Encryption (COSE):
Initial Algorithms", draft-ietf-cose-rfc8152bis-algs-12
(work in progress), September 2020.
[I-D.ietf-cose-rfc8152bis-struct]
Schaad, J., "CBOR Object Signing and Encryption (COSE):
Structures and Process", draft-ietf-cose-rfc8152bis-
struct-14 (work in progress), September 2020.
[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>.
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[RFC6690] Shelby, Z., "Constrained RESTful Environments (CoRE) Link
Format", RFC 6690, DOI 10.17487/RFC6690, August 2012,
<https://www.rfc-editor.org/info/rfc6690>.
[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>.
[RFC7252] Shelby, Z., Hartke, K., and C. Bormann, "The Constrained
Application Protocol (CoAP)", RFC 7252,
DOI 10.17487/RFC7252, June 2014,
<https://www.rfc-editor.org/info/rfc7252>.
[RFC7641] Hartke, K., "Observing Resources in the Constrained
Application Protocol (CoAP)", RFC 7641,
DOI 10.17487/RFC7641, September 2015,
<https://www.rfc-editor.org/info/rfc7641>.
[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>.
[RFC8613] Selander, G., Mattsson, J., Palombini, F., and L. Seitz,
"Object Security for Constrained RESTful Environments
(OSCORE)", RFC 8613, DOI 10.17487/RFC8613, July 2019,
<https://www.rfc-editor.org/info/rfc8613>.
7.2. Informative References
[I-D.hartke-t2trg-coral-reef]
Hartke, K., "Resource Discovery in Constrained RESTful
Environments (CoRE) using the Constrained RESTful
Application Language (CoRAL)", draft-hartke-t2trg-coral-
reef-04 (work in progress), May 2020.
[I-D.ietf-ace-dtls-authorize]
Gerdes, S., Bergmann, O., Bormann, C., Selander, G., and
L. Seitz, "Datagram Transport Layer Security (DTLS)
Profile for Authentication and Authorization for
Constrained Environments (ACE)", draft-ietf-ace-dtls-
authorize-14 (work in progress), October 2020.
[I-D.ietf-core-resource-directory]
Shelby, Z., Koster, M., Bormann, C., Stok, P., and C.
Amsuess, "CoRE Resource Directory", draft-ietf-core-
resource-directory-25 (work in progress), July 2020.
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[I-D.ietf-tls-dtls13]
Rescorla, E., Tschofenig, H., and N. Modadugu, "The
Datagram Transport Layer Security (DTLS) Protocol Version
1.3", draft-ietf-tls-dtls13-38 (work in progress), May
2020.
[I-D.tiloca-core-oscore-discovery]
Tiloca, M., Amsuess, C., and P. Stok, "Discovery of OSCORE
Groups with the CoRE Resource Directory", draft-tiloca-
core-oscore-discovery-07 (work in progress), November
2020.
[RFC6347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer
Security Version 1.2", RFC 6347, DOI 10.17487/RFC6347,
January 2012, <https://www.rfc-editor.org/info/rfc6347>.
[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>.
Appendix A. Document Updates
RFC EDITOR: PLEASE REMOVE THIS SECTION.
A.1. Version -00 to -01
o Names of application groups as status parameter.
o Parameters related to the pairwise mode of Group OSCORE.
o Defined FETCH for group-configuration resources.
o Policies on registration of links to the Resource Directory.
o Added resource type for group-configuration resources.
o Fixes, clarifications and editorial improvements.
Acknowledgments
The authors sincerely thank Christian Amsuess, Carsten Bormann and
Jim Schaad for their comments and feedback.
The work on this document has been partly supported by VINNOVA and
the Celtic-Next project CRITISEC; and by the H2020 project SIFIS-Home
(Grant agreement 952652).
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Authors' Addresses
Marco Tiloca
RISE AB
Isafjordsgatan 22
Kista SE-16440 Stockholm
Sweden
Email: marco.tiloca@ri.se
Rikard Hoeglund
RISE AB
Isafjordsgatan 22
Kista SE-16440 Stockholm
Sweden
Email: rikard.hoglund@ri.se
Peter van der Stok
Consultant
Phone: +31-492474673 (Netherlands), +33-966015248 (France)
Email: consultancy@vanderstok.org
URI: www.vanderstok.org
Francesca Palombini
Ericsson AB
Torshamnsgatan 23
Kista SE-16440 Stockholm
Sweden
Email: francesca.palombini@ericsson.com
Klaus Hartke
Ericsson AB
Torshamnsgatan 23
Kista SE-16440 Stockholm
Sweden
Email: klaus.hartke@ericsson.com
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