Internet DRAFT - draft-selander-ace-coap-est-oscore
draft-selander-ace-coap-est-oscore
ACE Working Group G. Selander
Internet-Draft Ericsson AB
Intended status: Standards Track S. Raza
Expires: 13 September 2023 RISE
M. Furuhed
Nexus
M. Vučinić
Inria
T. Claeys
12 March 2023
Protecting EST Payloads with OSCORE
draft-selander-ace-coap-est-oscore-06
Abstract
This document specifies public-key certificate enrollment procedures
protected with lightweight application-layer security protocols
suitable for Internet of Things (IoT) deployments. The protocols
leverage payload formats defined in Enrollment over Secure Transport
(EST) and existing IoT standards including the Constrained
Application Protocol (CoAP), Concise Binary Object Representation
(CBOR) and the CBOR Object Signing and Encryption (COSE) format.
Discussion Venues
This note is to be removed before publishing as an RFC.
Discussion of this document takes place on the Authentication and
Authorization for Constrained Environments Working Group mailing list
(ace@ietf.org), which is archived at
https://mailarchive.ietf.org/arch/browse/ace/.
Source for this draft and an issue tracker can be found at
https://github.com/EricssonResearch/EST-OSCORE.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 13 September 2023.
Copyright Notice
Copyright (c) 2023 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 (https://trustee.ietf.org/
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Please review these documents carefully, as they describe your rights
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provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Operational Differences with EST-coaps . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Authentication . . . . . . . . . . . . . . . . . . . . . . . 5
3.1. EDHOC . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.2. Certificate-based Authentication . . . . . . . . . . . . 6
3.3. Channel Binding . . . . . . . . . . . . . . . . . . . . . 6
3.4. Optimizations . . . . . . . . . . . . . . . . . . . . . . 7
4. Protocol Design and Layering . . . . . . . . . . . . . . . . 7
4.1. Discovery and URI . . . . . . . . . . . . . . . . . . . . 8
4.2. Mandatory/optional EST Functions . . . . . . . . . . . . 8
4.3. Payload formats . . . . . . . . . . . . . . . . . . . . . 9
4.4. Message Bindings . . . . . . . . . . . . . . . . . . . . 10
4.5. CoAP response codes . . . . . . . . . . . . . . . . . . . 11
4.6. Message fragmentation . . . . . . . . . . . . . . . . . . 11
4.7. Delayed Responses . . . . . . . . . . . . . . . . . . . . 11
4.8. Enrollment of Static DH Keys . . . . . . . . . . . . . . 11
5. HTTP-CoAP Proxy . . . . . . . . . . . . . . . . . . . . . . . 12
6. Security Considerations . . . . . . . . . . . . . . . . . . . 13
7. Privacy Considerations . . . . . . . . . . . . . . . . . . . 13
8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 13
8.1. EDHOC Exporter Label Registry . . . . . . . . . . . . . . 13
9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 13
10. References . . . . . . . . . . . . . . . . . . . . . . . . . 13
10.1. Normative References . . . . . . . . . . . . . . . . . . 13
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10.2. Informative References . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16
1. Introduction
One of the challenges with deploying a Public Key Infrastructure
(PKI) for the Internet of Things (IoT) is certificate enrollment,
because existing enrollment protocols are not optimized for
constrained environments [RFC7228].
One optimization of certificate enrollment targeting IoT deployments
is specified in EST-coaps ([RFC9148]), which defines a version of
Enrollment over Secure Transport [RFC7030] for transporting EST
payloads over CoAP [RFC7252] and DTLS [RFC6347], instead of secured
HTTP.
This document describes a method for protecting EST payloads over
CoAP or HTTP with OSCORE [RFC8613]. OSCORE specifies an extension to
CoAP which protects the application layer message and can be applied
independently of how CoAP messages are transported. OSCORE can also
be applied to CoAP-mappable HTTP which enables end-to-end security
for mixed CoAP and HTTP transfer of application layer data. Hence
EST payloads can be protected end-to-end independent of underlying
transport and through proxies translating between between CoAP and
HTTP.
OSCORE is designed for constrained environments, building on IoT
standards such as CoAP, CBOR [RFC7049] and COSE [RFC8152], and has in
particular gained traction in settings where message sizes and the
number of exchanged messages needs to be kept at a minimum, such as
6TiSCH [RFC9031], or for securing multicast CoAP messages
[I-D.ietf-core-oscore-groupcomm]. Where OSCORE is implemented and
used for communication security, the reuse of OSCORE for other
purposes, such as enrollment, reduces the code footprint.
In order to protect certificate enrollment with OSCORE, the necessary
keying material (notably, the OSCORE Master Secret, see [RFC8613])
needs to be established between EST-oscore client and EST-oscore
server. For this purpose we assume by default the use of the
lightweight authenticated key exchange protocol EDHOC
[I-D.ietf-lake-edhoc], although pre-shared OSCORE keying material
would also be an option.
Other ways to optimize the performance of certificate enrollment and
certificate based authentication described in this draft include the
use of:
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* Compact representations of X.509 certificates (see
[I-D.ietf-cose-cbor-encoded-cert])
* Certificates by reference (see [I-D.ietf-cose-x509])
* Compact, CBOR representations of EST payloads (see
[I-D.ietf-cose-cbor-encoded-cert])
1.1. Operational Differences with EST-coaps
The protection of EST payloads defined in this document builds on
EST-coaps [RFC9148] but transport layer security is replaced, or
complemented, by protection of the transfer- and application layer
data (i.e., CoAP message fields and payload). This specification
deviates from EST-coaps in the following respects:
* The DTLS record layer is replaced, or complemented, with OSCORE.
* The DTLS handshake is replaced, or complemented, with the
lightweight authenticated key exchange protocol EDHOC
[I-D.ietf-lake-edhoc], and makes use of the following features:
- Authentication based on certificates is complemented with
authentication based on raw public keys.
- Authentication based on signature keys is complemented with
authentication based on static Diffie-Hellman keys, for
certificates/raw public keys.
- Authentication based on certificate by value is complemented
with authentication based on certificate/raw public keys by
reference.
* The EST payloads protected by OSCORE can be proxied between
constrained networks supporting CoAP/CoAPs and non-constrained
networks supporting HTTP/HTTPs with a CoAP-HTTP proxy protection
without any security processing in the proxy (see Section 5). The
concept "Registrar" and its required trust relation with EST
server as described in Section 5 of [RFC9148] is therefore
redundant.
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So, while the same authentication scheme (Diffie-Hellman key exchange
authenticated with transported certificates) and the same EST
payloads as EST-coaps also apply to EST-oscore, the latter specifies
other authentication schemes and a new matching EST function. The
reason for these deviations is that a significant overhead can be
removed in terms of message sizes and round trips by using a
different handshake, public key type or transported credential, and
those are independent of the actual enrollment procedure.
2. Terminology
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. These
words may also appear in this document in lowercase, absent their
normative meanings.
This document uses terminology from [RFC9148] which in turn is based
on [RFC7030] and, in turn, on [RFC5272].
The term "Trust Anchor" follows the terminology of [RFC6024]: "A
trust anchor represents an authoritative entity via a public key and
associated data. The public key is used to verify digital
signatures, and the associated data is used to constrain the types of
information for which the trust anchor is authoritative." One
example of specifying more compact alternatives to X.509 certificates
for exchanging trust anchor information is provided by the
TrustAnchorInfo structure of [RFC5914], the mandatory parts of which
essentially is the SubjectPublicKeyInfo structure [RFC5280], i.e., an
algorithm identifier followed by a public key.
3. Authentication
This specification replaces the DTLS handshake in EST-coaps with the
lightweight authenticated key exchange protocol EDHOC
[I-D.ietf-lake-edhoc]. During initial enrollment the EST-oscore
client and server run EDHOC [I-D.ietf-lake-edhoc] to authenticate and
establish the OSCORE security context with which the EST payloads are
protected.
EST-oscore clients and servers MUST perform mutual authentication.
The EST server and EST client are responsible for ensuring that an
acceptable cipher suite is negotiated. The client MUST authenticate
the server before accepting any server response. The server MUST
authenticate the client and provide relevant information to the CA
for decision about issuing a certificate.
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3.1. EDHOC
EDHOC supports authentication with certificates/raw public keys
(referred to as "credentials"), and the credentials may either be
transported in the protocol, or referenced. This is determined by
the identifier of the credential of the endpoint, ID_CRED_x for x=
Initiator/Responder, which is transported in an EDHOC message. This
identifier may be the credential itself (in which case the credential
is transported), or a pointer such as a URI to the credential (e.g.,
x5t, see [I-D.ietf-cose-x509]) or some other identifier which enables
the receiving endpoint to retrieve the credential.
3.2. Certificate-based Authentication
EST-oscore, like EST-coaps, supports certificate-based authentication
between EST client and server. In this case the client MUST be
configured with an Implicit or Explicit Trust Anchor (TA) [RFC7030]
database, enabling the client to authenticate the server. During the
initial enrollment the client SHOULD populate its Explicit TA
database and use it for subsequent authentications.
The EST client certificate SHOULD conform to [RFC7925]. The EST
client and/or EST server certificate MAY be a (natively signed) CBOR
certificate [I-D.ietf-cose-cbor-encoded-cert].
3.3. Channel Binding
The [RFC5272] specification describes proof-of-possession as the
ability of a client to prove its possession of a private key which is
linked to a certified public key. In case of signature key, a proof-
of-possession is generated by the client when it signs the PKCS#10
Request during the enrollment phase. Connection-based proof-of-
possession is OPTIONAL for EST-oscore clients and servers.
When desired the client can use the EDHOC-Exporter API to extract
channel-binding information and provide a connection-based proof-of
possession. Channel-binding information is obtained as follows
edhoc-unique = EDHOC-Exporter(TBD1, "EDHOC Unique", length),
where TBD1 is a registered label from the EDHOC Exporter Label
registry, length equals the desired length of the edhoc-unique byte
string. The client then adds the edhoc-unique byte string as a
challengePassword (see Section 5.4.1 of [RFC2985]) in the attributes
section of the PKCS#10 Request [RFC2986] to prove to the server that
the authenticated EDHOC client is in possession of the private key
associated with the certification request, and signed the
certification request after the EDHOC session was established.
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3.4. Optimizations
* The last message of the EDHOC protocol, message_3, MAY be combined
with an OSCORE request, enabling authenticated Diffie-Hellman key
exchange and a protected CoAP request/response (which may contain
an enrolment request and response) in two round trips
[I-D.ietf-core-oscore-edhoc].
* The certificates MAY be compressed, e.g. using the CBOR encoding
defined in [I-D.ietf-cose-cbor-encoded-cert].
* The certificate MAY be referenced instead of transported
[I-D.ietf-cose-x509]. The EST-oscore server MAY use information
in the credential identifier field of the EDHOC message
(ID_CRED_x) to access the EST-oscore client certificate, e.g., in
a directory or database provided by the issuer. In this case the
certificate may not need to be transported over a constrained link
between EST client and server.
* Conversely, the response to the PKCS#10 request MAY be a reference
to the enrolled certificate rather than the certificate itself.
The EST-oscore server MAY in the enrolment response to the EST-
oscore client include a pointer to a directory or database where
the certificate can be retrieved.
4. Protocol Design and Layering
EST-oscore uses CoAP [RFC7252] and Block-Wise [RFC7959] to transfer
EST messages in the same way as [RFC9148]. Instead of DTLS record
layer, OSCORE [RFC8613] is used to protect the EST payloads. DTLS
handshake is replaced with EDHOC [I-D.ietf-lake-edhoc]. Figure 1
below shows the layered EST-oscore architecture.
+----------------+
| EST messages |
+------------+----------------+
| EDHOC | OSCORE |
+------------+----------------+
| CoAP or HTTP |
+-----------------------------+
| UDP or TCP |
+-----------------------------+
Figure 1: EST protected with OSCORE.
EST-oscore follows much of the EST-coaps and EST design.
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4.1. Discovery and URI
The discovery of EST resources and the definition of the short EST-
coaps URI paths specified in Section 4.1 of [RFC9148], as well as the
new Resource Type defined in Section 8.2 of [RFC9148] apply to EST-
oscore. Support for OSCORE is indicated by the "osc" attribute
defined in Section 9 of [RFC8613], for example:
REQ: GET /.well-known/core?rt=ace.est.sen
RES: 2.05 Content
</est>; rt="ace.est";osc
4.2. Mandatory/optional EST Functions
The EST-oscore specification has the same set of required-to-
implement functions as EST-coaps. The content of Table 1 is adapted
from Section 4.2 in [RFC9148] and uses the updated URI paths (see
Section 4.1).
+===============+===========================+
| EST functions | EST-oscore implementation |
+===============+===========================+
| /crts | MUST |
+---------------+---------------------------+
| /sen | MUST |
+---------------+---------------------------+
| /sren | MUST |
+---------------+---------------------------+
| /skg | OPTIONAL |
+---------------+---------------------------+
| /skc | OPTIONAL |
+---------------+---------------------------+
| /att | OPTIONAL |
+---------------+---------------------------+
Table 1: Mandatory and optional EST-
oscore functions
4.2.1. /crts
EST-coaps provides the /crts operation. A successful request from
the client to this resource will be answered with a bag of
certificates which is subsequently installed in the Explicit TA.
A trust anchor is commonly a self-signed certificate of the CA public
key. In order to reduce transport overhead, the trust anchor could
be just the CA public key and associated data (see Section 2), e.g.,
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the SubjectPublicKeyInfo, or a public key certificate without the
signature. In either case they can be compactly encoded, e.g. using
CBOR encoding [I-D.ietf-cose-cbor-encoded-cert].
4.3. Payload formats
Similar to EST-coaps, EST-oscore allows transport of the ASN.1
structure of a given Media-Type in binary format. In addition, EST-
oscore uses the same CoAP Content-Format Options to transport EST
requests and responses . Table 2 summarizes the information from
Section 4.3 in [RFC9148].
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+=======+===================================+=======+
| URI | Content-Format | #IANA |
+=======+===================================+=======+
| /crts | N/A (req) | - |
+-------+-----------------------------------+-------+
| | application/pkix-cert (res) | 287 |
+-------+-----------------------------------+-------+
| | application/pkcs-7-mime;smime- | 281 |
| | type=certs-only (res) | |
+-------+-----------------------------------+-------+
| /sen | application/pkcs10 (req) | 286 |
+-------+-----------------------------------+-------+
| | application/pkix-cert (res) | 287 |
+-------+-----------------------------------+-------+
| | application/pkcs-7-mime;smime- | 281 |
| | type=certs-only (res) | |
+-------+-----------------------------------+-------+
| /sren | application/pkcs10 (req) | 286 |
+-------+-----------------------------------+-------+
| | application/pkix-cert (res) | 287 |
+-------+-----------------------------------+-------+
| | application/pkcs-7-mime;smime- | 281 |
| | type=certs-only (res) | |
+-------+-----------------------------------+-------+
| /skg | application/pkcs10 (req) | 286 |
+-------+-----------------------------------+-------+
| | application/multipart-core (res) | 62 |
+-------+-----------------------------------+-------+
| /skc | application/pkcs10 (req) | 286 |
+-------+-----------------------------------+-------+
| | application/multipart-core (res) | 62 |
+-------+-----------------------------------+-------+
| /att | N/A (req) | - |
+-------+-----------------------------------+-------+
| | application/csrattrs (res) | 285 |
+-------+-----------------------------------+-------+
Table 2: EST functions and there associated
Media-Type and IANA numbers
4.4. Message Bindings
The EST-oscore message characteristics are identical to those
specified in Section 4.4 of [RFC9148]. It is RECOMMENDED that
* The EST-oscore endpoints support delayed responses
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* The endpoints supports the following CoAP options: OSCORE, Uri-
Host, Uri-Path, Uri-Port, Content-Format, Block1, Block2, and
Accept.
* The EST URLs based on https:// are translated to coap://, but with
mandatory use of the CoAP OSCORE option.
4.5. CoAP response codes
See Section 4.5 in [RFC9148].
4.6. Message fragmentation
The EDHOC key exchange is optimized for message overhead, in
particular the use of static DH keys instead of signature keys for
authentication (e.g., method 3 of [I-D.ietf-lake-edhoc]). Together
with various measures listed in this document such as CBOR-encoded
payloads ([I-D.ietf-cose-cbor-encoded-cert]), CBOR certificates
[I-D.ietf-cose-cbor-encoded-cert], certificates by reference
(Section 3.4), and trust anchors without signature (Section 4.2.1), a
significant reduction of message sizes can be achieved.
Nevertheless, depending on application, the protocol messages may
become larger than available frame size resulting in fragmentation
and, in resource constrained networks such as IEEE 802.15.4 where
throughput is limited, fragment loss can trigger costly
retransmissions.
It is RECOMMENDED to prevent IP fragmentation, since it involves an
error-prone datagram reconstitution. To limit the size of the CoAP
payload, this specification mandates the implementation of CoAP
option Block1 and Block2 fragmentation mechanism [RFC7959] as
described in Section 4.6 of [RFC9148].
4.7. Delayed Responses
See Section 4.7 in [RFC9148].
4.8. Enrollment of Static DH Keys
This section specifies how the EST client enrolls a static DH key.
Because a DH key pair cannot be used for signing operations, the EST
client attempting to enroll a DH key must use an alternative proof-
of-possesion algorithm. The EST client obtained the CA certs
including the CA's DH certificate using the /crts function. The
certificate indicates the DH group parameters which MUST be respected
by the EST client when generating its own DH key pair. The EST
client prepares the PKCS #10 object and signs it by following the
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steps in Section 4 of [RFC6955]. The Key Derivation Function (KDF)
and the MAC MUST be set to the HDKF and HMAC algorithms used by
OSCORE. As per [RFC8613], the HKDF MUST be one of the HMAC-based
HKDF [RFC5869] algorithms defined for COSE [RFC9052]. The KDF and
MAC is thus defined by the hash algorithm used by OSCORE in HKDF and
HMAC, which by default is SHA-256. When EDHOC is used, then the hash
algorithm is the application hash algorithm of the selected cipher
suite.
5. HTTP-CoAP Proxy
As noted in Section 5 of [RFC9148], in real-world deployments, the
EST server will not always reside within the CoAP boundary. The EST-
server can exist outside the constrained network in a non-constrained
network that supports HTTP but not CoAP, thus requiring an
intermediary CoAP-to-HTTP proxy.
Since OSCORE is applicable to CoAP-mappable HTTP (see Section 11 of
[RFC8613]) the EST payloads can be protected end-to-end between EST
client and EST server independent of transport protocol or potential
transport layer security which may need to be terminated in the
proxy, see Figure 2. Therefore the concept "Registrar" and its
required trust relation with EST server as described in Section 5 of
[RFC9148] is redundant.
The mappings between CoAP and HTTP referred to in Section 8.1 of
[RFC9148] apply, and additional mappings resulting from the use of
OSCORE are specified in Section 11 of [RFC8613].
OSCORE provides end-to-end security between EST Server and EST
Client. The use of TLS and DTLS is optional.
Constrained-Node Network
.---------. .----------------------------.
| CA | |.--------------------------.|
'---------' || ||
| || ||
.------. HTTP .-----------------. CoAP .-----------. ||
| EST |<------->| CoAP-to-HTTP |<-------->| EST Client| ||
|Server| (TLS) | Proxy | (DTLS) '-----------' ||
'------' '-----------------' ||
|| ||
<------------------------------------------------> ||
OSCORE || ||
|'--------------------------'|
'----------------------------'
Figure 2: CoAP-to-HTTP proxy at the CoAP boundary.
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6. Security Considerations
TBD: Compare with RFC9148
TBD: Channel binding security considerations: 3SHAKE attack and
EDHOC.
7. Privacy Considerations
TBD
8. IANA Considerations
8.1. EDHOC Exporter Label Registry
IANA is requested to register the following entry in the "EDHOC
Exporter Label" registry under the group name "Ephemeral Diffie-
Hellman Over COSE (EDHOC).
+-------------+------------------------------+-------------------+
| Label | Description | Reference |
+=============+==============================+===================+
| TBD1 | EDHOC unique | [[this document]] |
+-------------+------------------------------+-------------------+
Figure 3: EDHOC Exporter Label
9. Acknowledgments
10. References
10.1. Normative References
[I-D.ietf-lake-edhoc]
Selander, G., Mattsson, J. P., and F. Palombini,
"Ephemeral Diffie-Hellman Over COSE (EDHOC)", Work in
Progress, Internet-Draft, draft-ietf-lake-edhoc-19, 3
February 2023, <https://datatracker.ietf.org/doc/html/
draft-ietf-lake-edhoc-19>.
[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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[RFC5869] Krawczyk, H. and P. Eronen, "HMAC-based Extract-and-Expand
Key Derivation Function (HKDF)", RFC 5869,
DOI 10.17487/RFC5869, May 2010,
<https://www.rfc-editor.org/info/rfc5869>.
[RFC6955] Schaad, J. and H. Prafullchandra, "Diffie-Hellman Proof-
of-Possession Algorithms", RFC 6955, DOI 10.17487/RFC6955,
May 2013, <https://www.rfc-editor.org/info/rfc6955>.
[RFC7049] Bormann, C. and P. Hoffman, "Concise Binary Object
Representation (CBOR)", RFC 7049, DOI 10.17487/RFC7049,
October 2013, <https://www.rfc-editor.org/info/rfc7049>.
[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>.
[RFC7925] Tschofenig, H., Ed. and T. Fossati, "Transport Layer
Security (TLS) / Datagram Transport Layer Security (DTLS)
Profiles for the Internet of Things", RFC 7925,
DOI 10.17487/RFC7925, July 2016,
<https://www.rfc-editor.org/info/rfc7925>.
[RFC7959] Bormann, C. and Z. Shelby, Ed., "Block-Wise Transfers in
the Constrained Application Protocol (CoAP)", RFC 7959,
DOI 10.17487/RFC7959, August 2016,
<https://www.rfc-editor.org/info/rfc7959>.
[RFC8152] Schaad, J., "CBOR Object Signing and Encryption (COSE)",
RFC 8152, DOI 10.17487/RFC8152, July 2017,
<https://www.rfc-editor.org/info/rfc8152>.
[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>.
[RFC9052] Schaad, J., "CBOR Object Signing and Encryption (COSE):
Structures and Process", STD 96, RFC 9052,
DOI 10.17487/RFC9052, August 2022,
<https://www.rfc-editor.org/info/rfc9052>.
[RFC9148] van der Stok, P., Kampanakis, P., Richardson, M., and S.
Raza, "EST-coaps: Enrollment over Secure Transport with
the Secure Constrained Application Protocol", RFC 9148,
DOI 10.17487/RFC9148, April 2022,
<https://www.rfc-editor.org/info/rfc9148>.
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10.2. Informative References
[I-D.ietf-core-oscore-edhoc]
Palombini, F., Tiloca, M., Höglund, R., Hristozov, S., and
G. Selander, "Profiling EDHOC for CoAP and OSCORE", Work
in Progress, Internet-Draft, draft-ietf-core-oscore-edhoc-
06, 23 November 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-core-
oscore-edhoc-06>.
[I-D.ietf-core-oscore-groupcomm]
Tiloca, M., Selander, G., Palombini, F., Mattsson, J. P.,
and J. Park, "Group OSCORE - Secure Group Communication
for CoAP", Work in Progress, Internet-Draft, draft-ietf-
core-oscore-groupcomm-17, 20 December 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-core-
oscore-groupcomm-17>.
[I-D.ietf-cose-cbor-encoded-cert]
Mattsson, J. P., Selander, G., Raza, S., Höglund, J., and
M. Furuhed, "CBOR Encoded X.509 Certificates (C509
Certificates)", Work in Progress, Internet-Draft, draft-
ietf-cose-cbor-encoded-cert-05, 10 January 2023,
<https://datatracker.ietf.org/doc/html/draft-ietf-cose-
cbor-encoded-cert-05>.
[I-D.ietf-cose-x509]
Schaad, J., "CBOR Object Signing and Encryption (COSE):
Header Parameters for Carrying and Referencing X.509
Certificates", Work in Progress, Internet-Draft, draft-
ietf-cose-x509-09, 13 October 2022,
<https://datatracker.ietf.org/doc/html/draft-ietf-cose-
x509-09>.
[RFC2985] Nystrom, M. and B. Kaliski, "PKCS #9: Selected Object
Classes and Attribute Types Version 2.0", RFC 2985,
DOI 10.17487/RFC2985, November 2000,
<https://www.rfc-editor.org/info/rfc2985>.
[RFC2986] Nystrom, M. and B. Kaliski, "PKCS #10: Certification
Request Syntax Specification Version 1.7", RFC 2986,
DOI 10.17487/RFC2986, November 2000,
<https://www.rfc-editor.org/info/rfc2986>.
[RFC5272] Schaad, J. and M. Myers, "Certificate Management over CMS
(CMC)", RFC 5272, DOI 10.17487/RFC5272, June 2008,
<https://www.rfc-editor.org/info/rfc5272>.
Selander, et al. Expires 13 September 2023 [Page 15]
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[RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List
(CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
<https://www.rfc-editor.org/info/rfc5280>.
[RFC5914] Housley, R., Ashmore, S., and C. Wallace, "Trust Anchor
Format", RFC 5914, DOI 10.17487/RFC5914, June 2010,
<https://www.rfc-editor.org/info/rfc5914>.
[RFC6024] Reddy, R. and C. Wallace, "Trust Anchor Management
Requirements", RFC 6024, DOI 10.17487/RFC6024, October
2010, <https://www.rfc-editor.org/info/rfc6024>.
[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>.
[RFC7030] Pritikin, M., Ed., Yee, P., Ed., and D. Harkins, Ed.,
"Enrollment over Secure Transport", RFC 7030,
DOI 10.17487/RFC7030, October 2013,
<https://www.rfc-editor.org/info/rfc7030>.
[RFC7228] Bormann, C., Ersue, M., and A. Keranen, "Terminology for
Constrained-Node Networks", RFC 7228,
DOI 10.17487/RFC7228, May 2014,
<https://www.rfc-editor.org/info/rfc7228>.
[RFC8392] Jones, M., Wahlstroem, E., Erdtman, S., and H. Tschofenig,
"CBOR Web Token (CWT)", RFC 8392, DOI 10.17487/RFC8392,
May 2018, <https://www.rfc-editor.org/info/rfc8392>.
[RFC9031] Vučinić, M., Ed., Simon, J., Pister, K., and M.
Richardson, "Constrained Join Protocol (CoJP) for 6TiSCH",
RFC 9031, DOI 10.17487/RFC9031, May 2021,
<https://www.rfc-editor.org/info/rfc9031>.
Authors' Addresses
Göran Selander
Ericsson AB
Email: goran.selander@ericsson.com
Shahid Raza
RISE
Email: shahid.raza@ri.se
Selander, et al. Expires 13 September 2023 [Page 16]
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Martin Furuhed
Nexus
Email: martin.furuhed@nexusgroup.com
Mališa Vučinić
Inria
Email: malisa.vucinic@inria.fr
Timothy Claeys
Email: timothy.claeys@gmail.com
Selander, et al. Expires 13 September 2023 [Page 17]
