Internet-Draft | extendedKeyUsage for IM URIs | October 2024 |
Mahy | Expires 17 April 2025 | [Page] |
RFC 5280 specifies several extended key purpose identifiers (KeyPurposeIds) for X.509 certificates. This document defines Instant Messaging (IM) identity KeyPurposeId for inclusion in the Extended Key Usage (EKU) extension of X.509 v3 public key certificates¶
This note is to be removed before publishing as an RFC.¶
The latest revision of this draft can be found at https://rohanmahy.github.io/mahy-lamps-im-keyusage/draft-ietf-lamps-im-keyusage.html. Status information for this document may be found at https://datatracker.ietf.org/doc/draft-ietf-lamps-im-keyusage/.¶
Discussion of this document takes place on the LAMPS WG Working Group mailing list (mailto:lamps@ietf.org), which is archived at https://mailarchive.ietf.org/arch/browse/lamps/. Subscribe at https://www.ietf.org/mailman/listinfo/lamps/.¶
Source for this draft and an issue tracker can be found at https://github.com/rohanmahy/mahy-lamps-im-keyusage.¶
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/.¶
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 17 April 2025.¶
Copyright (c) 2024 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/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License.¶
Instant Messaging (IM) systems using the Messaging Layer Security (MLS)
[RFC9420] protocol can incorporate per-client identity certificate
credentials. The subjectAltName of these certificates can be an IM URI or
XMPP URI, for example. Since IM clients could be very numerous, operators
are reticent to issue certificates for these users that might accidentally
be used to validate a TLS connection because it has the KeyPurposeId
id-kp-serverAuth
or id-kp-clientAuth
.¶
An explanation of MLS credentials as they apply to Instant Messaging is described in [I-D.barnes-mimi-identity-arch]. These credentials are expected to be heavily used in the More Instant Messaging Interoperability (MIMI) Working Group.¶
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.¶
This specification defines the KeyPurposeId id-kp-imUri, which MAY be used for signing messages to prove the identity of an Instant Messaging client. This Extended Key Usage is optionally critical.¶
id-kp OBJECT IDENTIFIER ::= { iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) kp(3) } id-kp-imUri OBJECT IDENTIFIER ::= { id-kp TBD1 }¶
The Security Considerations of [RFC5280] are applicable to this document. This extended key purpose does not introduce new security risks but instead reduces existing security risks by providing means to identify if the certificate is generated to sign IM identity credentials.¶
IANA is requested to register the following OIDs in the "SMI Security for PKIX Extended Key Purpose" registry (1.3.6.1.5.5.7.3). These OIDs are defined in Section 4.¶
Decimal | Description | References |
---|---|---|
TBD1 | id-kp-imUri | This-RFC |
IANA is also requested to register the following ASN.1 [ITU.X690.2021] module OID in the "SMI Security for PKIX Module Identifier" registry (1.3.6.1.5.5.7.0). This OID is defined in Appendix A.¶
Decimal | Description | References |
---|---|---|
TBD2 | id-mod-im-eku | This-RFC |
The following module adheres to ASN.1 specifications [ITU.X680.2021] and [ITU.X690.2021].¶
<CODE BEGINS> IM-EKU { iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) id-mod(0) id-mod-im-eku (TBD2) } DEFINITIONS IMPLICIT TAGS ::= BEGIN -- OID Arc id-kp OBJECT IDENTIFIER ::= { iso(1) identified-organization(3) dod(6) internet(1) security(5) mechanisms(5) pkix(7) kp(3) } -- Extended Key Usage Values id-kp-imUri OBJECT IDENTIFIER ::= { id-kp TBD1 } END <CODE ENDS>¶
RFC Editor, please remove this section on publication.¶
Thanks to Sean Turner and Russ Housley for reviews, suggestions, corrections, and encouragement.¶