Internet DRAFT - draft-ietf-netconf-keystore
draft-ietf-netconf-keystore
NETCONF Working Group K. Watsen
Internet-Draft Watsen Networks
Intended status: Standards Track 1 March 2024
Expires: 2 September 2024
A YANG Data Model for a Keystore and Keystore Operations
draft-ietf-netconf-keystore-34
Abstract
This document presents a YANG module called "ietf-keystore" that
enables centralized configuration of both symmetric and asymmetric
keys. The secret value for both key types may be encrypted or
hidden. Asymmetric keys may be associated with certificates.
Notifications are sent when certificates are about to expire.
Editorial Note (To be removed by RFC Editor)
This draft contains placeholder values that need to be replaced with
finalized values at the time of publication. This note summarizes
all of the substitutions that are needed. No other RFC Editor
instructions are specified elsewhere in this document.
Artwork in this document contains shorthand references to drafts in
progress. Please apply the following replacements:
* AAAA --> the assigned RFC value for draft-ietf-netconf-crypto-
types
* CCCC --> the assigned RFC value for this draft
Artwork in this document contains placeholder values for the date of
publication of this draft. Please apply the following replacement:
* 2024-03-02 --> the publication date of this draft
The "Relation to other RFCs" section Section 1.1 contains the text
"one or more YANG modules" and, later, "modules". This text is
sourced from a file in a context where it is unknown how many modules
a draft defines. The text is not wrong as is, but it may be improved
by stating more directly how many modules are defined.
The "Relation to other RFCs" section Section 1.1 contains a self-
reference to this draft, along with a corresponding reference in the
Appendix. Please replace the self-reference in this section with
"This RFC" (or similar) and remove the self-reference in the
"Normative/Informative References" section, whichever it is in.
Watsen Expires 2 September 2024 [Page 1]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
Tree-diagrams in this draft may use the '\' line-folding mode defined
in RFC 8792. However, nicer-to-the-eye is when the '\\' line-folding
mode is used. The AD suggested suggested putting a request here for
the RFC Editor to help convert "ugly" '\' folded examples to use the
'\\' folding mode. "Help convert" may be interpreted as, identify
what looks ugly and ask the authors to make the adjustment.
The following Appendix section is to be removed prior to publication:
* Appendix A. Change Log
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/.
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 2 September 2024.
Copyright Notice
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.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
Watsen Expires 2 September 2024 [Page 2]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
1.1. Relation to other RFCs . . . . . . . . . . . . . . . . . 4
1.2. Specification Language . . . . . . . . . . . . . . . . . 6
1.3. Terminology . . . . . . . . . . . . . . . . . . . . . . . 6
1.4. Adherence to the NMDA . . . . . . . . . . . . . . . . . . 7
1.5. Conventions . . . . . . . . . . . . . . . . . . . . . . . 7
2. The "ietf-keystore" Module . . . . . . . . . . . . . . . . . 7
2.1. Data Model Overview . . . . . . . . . . . . . . . . . . . 7
2.2. Example Usage . . . . . . . . . . . . . . . . . . . . . . 16
2.3. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 27
3. Support for Built-in Keys . . . . . . . . . . . . . . . . . . 36
4. Encrypting Keys in Configuration . . . . . . . . . . . . . . 38
5. Security Considerations . . . . . . . . . . . . . . . . . . . 42
5.1. Security of Data at Rest and in Motion . . . . . . . . . 42
5.2. Unconstrained Private Key Usage . . . . . . . . . . . . . 42
5.3. Considerations for the "ietf-keystore" YANG Module . . . 42
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 43
6.1. The "IETF XML" Registry . . . . . . . . . . . . . . . . . 44
6.2. The "YANG Module Names" Registry . . . . . . . . . . . . 44
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 44
7.1. Normative References . . . . . . . . . . . . . . . . . . 44
7.2. Informative References . . . . . . . . . . . . . . . . . 45
Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 47
A.1. 00 to 01 . . . . . . . . . . . . . . . . . . . . . . . . 47
A.2. 01 to 02 . . . . . . . . . . . . . . . . . . . . . . . . 47
A.3. 02 to 03 . . . . . . . . . . . . . . . . . . . . . . . . 47
A.4. 03 to 04 . . . . . . . . . . . . . . . . . . . . . . . . 48
A.5. 04 to 05 . . . . . . . . . . . . . . . . . . . . . . . . 48
A.6. 05 to 06 . . . . . . . . . . . . . . . . . . . . . . . . 48
A.7. 06 to 07 . . . . . . . . . . . . . . . . . . . . . . . . 48
A.8. 07 to 08 . . . . . . . . . . . . . . . . . . . . . . . . 48
A.9. 08 to 09 . . . . . . . . . . . . . . . . . . . . . . . . 49
A.10. 09 to 10 . . . . . . . . . . . . . . . . . . . . . . . . 49
A.11. 10 to 11 . . . . . . . . . . . . . . . . . . . . . . . . 49
A.12. 11 to 12 . . . . . . . . . . . . . . . . . . . . . . . . 50
A.13. 12 to 13 . . . . . . . . . . . . . . . . . . . . . . . . 50
A.14. 13 to 14 . . . . . . . . . . . . . . . . . . . . . . . . 50
A.15. 14 to 15 . . . . . . . . . . . . . . . . . . . . . . . . 50
A.16. 15 to 16 . . . . . . . . . . . . . . . . . . . . . . . . 50
A.17. 16 to 17 . . . . . . . . . . . . . . . . . . . . . . . . 50
A.18. 17 to 18 . . . . . . . . . . . . . . . . . . . . . . . . 51
A.19. 18 to 19 . . . . . . . . . . . . . . . . . . . . . . . . 51
A.20. 19 to 20 . . . . . . . . . . . . . . . . . . . . . . . . 51
A.21. 20 to 21 . . . . . . . . . . . . . . . . . . . . . . . . 51
A.22. 21 to 22 . . . . . . . . . . . . . . . . . . . . . . . . 52
A.23. 22 to 23 . . . . . . . . . . . . . . . . . . . . . . . . 52
A.24. 23 to 24 . . . . . . . . . . . . . . . . . . . . . . . . 52
A.25. 24 to 25 . . . . . . . . . . . . . . . . . . . . . . . . 52
A.26. 25 to 26 . . . . . . . . . . . . . . . . . . . . . . . . 53
Watsen Expires 2 September 2024 [Page 3]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
A.27. 26 to 27 . . . . . . . . . . . . . . . . . . . . . . . . 53
A.28. 27 to 28 . . . . . . . . . . . . . . . . . . . . . . . . 53
A.29. 28 to 29 . . . . . . . . . . . . . . . . . . . . . . . . 53
A.30. 29 to 30 . . . . . . . . . . . . . . . . . . . . . . . . 53
A.31. 30 to 31 . . . . . . . . . . . . . . . . . . . . . . . . 53
A.32. 31 to 33 . . . . . . . . . . . . . . . . . . . . . . . . 53
A.33. 33 to 34 . . . . . . . . . . . . . . . . . . . . . . . . 54
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 54
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 54
1. Introduction
This document presents a YANG 1.1 [RFC7950] module called "ietf-
keystore" that enables centralized configuration of both symmetric
and asymmetric keys. The secret value for both key types may be
encrypted or hidden (see [I-D.ietf-netconf-crypto-types]).
Asymmetric keys may be associated with certificates. Notifications
are sent when certificates are about to expire.
The "ietf-keystore" module defines many "grouping" statements
intended for use by other modules that may import it. For instance,
there are groupings that define enabling a key to be either
configured inline (within the defining data model) or as a reference
to a key in the central keystore.
Special consideration has been given for servers that have
cryptographic hardware, such as a Trusted Platform Module (TPM).
These servers are unique in that the cryptographic hardware hides the
secret key values. Additionally, such hardware is commonly
initialized when manufactured to protect a "built-in" asymmetric key
for which its public half is conveyed in an identity certificate
(e.g., an IDevID [Std-802.1AR-2018] certificate). Please see
Section 3 to see how built-in keys are supported.
This document is intended to reflect existing practices that many
server implementations support at the time of writing. To simplify
implementation, advanced key formats may be selectively implemented.
Implementations may utilize operating-system level keystore utilities
(e.g., "Keychain Access" on MacOS) and/or cryptographic hardware
(e.g., TPMs).
1.1. Relation to other RFCs
This document presents one or more YANG modules [RFC7950] that are
part of a collection of RFCs that work together to, ultimately,
support the configuration of both the clients and servers of both the
NETCONF [RFC6241] and RESTCONF [RFC8040] protocols.
Watsen Expires 2 September 2024 [Page 4]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
The dependency relationship between the primary YANG groupings
defined in the various RFCs is presented in the below diagram. In
some cases, a draft may define secondary groupings that introduce
dependencies not illustrated in the diagram. The labels in the
diagram are a shorthand name for the defining RFC. The citation
reference for shorthand name is provided below the diagram.
Please note that the arrows in the diagram point from referencer to
referenced. For example, the "crypto-types" RFC does not have any
dependencies, whilst the "keystore" RFC depends on the "crypto-types"
RFC.
crypto-types
^ ^
/ \
/ \
truststore keystore
^ ^ ^ ^
| +---------+ | |
| | | |
| +------------+ |
tcp-client-server | / | |
^ ^ ssh-client-server | |
| | ^ tls-client-server
| | | ^ ^ http-client-server
| | | | | ^
| | | +-----+ +---------+ |
| | | | | |
| +-----------|--------|--------------+ | |
| | | | | |
+-----------+ | | | | |
| | | | | |
| | | | | |
netconf-client-server restconf-client-server
Watsen Expires 2 September 2024 [Page 5]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
+======================+===========================================+
|Label in Diagram | Originating RFC |
+======================+===========================================+
|crypto-types | [I-D.ietf-netconf-crypto-types] |
+----------------------+-------------------------------------------+
|truststore | [I-D.ietf-netconf-trust-anchors] |
+----------------------+-------------------------------------------+
|keystore | [I-D.ietf-netconf-keystore] |
+----------------------+-------------------------------------------+
|tcp-client-server | [I-D.ietf-netconf-tcp-client-server] |
+----------------------+-------------------------------------------+
|ssh-client-server | [I-D.ietf-netconf-ssh-client-server] |
+----------------------+-------------------------------------------+
|tls-client-server | [I-D.ietf-netconf-tls-client-server] |
+----------------------+-------------------------------------------+
|http-client-server | [I-D.ietf-netconf-http-client-server] |
+----------------------+-------------------------------------------+
|netconf-client-server | [I-D.ietf-netconf-netconf-client-server] |
+----------------------+-------------------------------------------+
|restconf-client-server| [I-D.ietf-netconf-restconf-client-server] |
+----------------------+-------------------------------------------+
Table 1: Label in Diagram to RFC Mapping
1.2. Specification Language
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.
1.3. Terminology
The terms "client" and "server" are defined in [RFC6241] and are not
redefined here.
The term "keystore" is defined in this document as a mechanism that
intends to safeguard secrets.
The nomenclature "<running>" and "<operational>" are defined in
[RFC8342].
The sentence fragments "augmented" and "augmented in" are used herein
as the past tense verbified form of the "augment" statement defined
in Section 7.17 of [RFC7950].
Watsen Expires 2 September 2024 [Page 6]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
The term "key" may be used to mean one of three things in this
document: 1) the YANG-defined "asymmetric-key" or "symmetric-key"
node defined in this document, 2) the raw key data possessed by the
aforementioned key nodes, and 3) the "key" of a YANG "list"
statement. This document attempts to always qualify types '2' and
'3' using, "raw key value" and "YANG list key" where needed. In all
other cases, an unqualified "key" refers to a YANG-defined
"asymmetric-key" or "symmetric-key" node.
1.4. Adherence to the NMDA
This document is compliant with Network Management Datastore
Architecture (NMDA) [RFC8342]. For instance, keys and associated
certificates installed during manufacturing (e.g., for an IDevID
certificate) are expected to appear in <operational> (see Section 3).
1.5. Conventions
Various examples in this document use "BASE64VALUE=" as a placeholder
value for binary data that has been base64 encoded (per Section 9.8
of [RFC7950]). This placeholder value is used because real base64
encoded structures are often many lines long and hence distracting to
the example being presented.
This document uses the adjective "central" to the word "keystore" to
refer to the top-level instance of the "keystore-grouping", when the
"central-keystore-supported" feature is enabled. Please be aware
that consuming YANG modules MAY instantiate the "keystore-grouping"
in other locations. All such other instances are not the "central"
instance.
2. The "ietf-keystore" Module
This section defines a YANG 1.1 [RFC7950] module called "ietf-
keystore". A high-level overview of the module is provided in
Section 2.1. Examples illustrating the module's use are provided in
Section 2.2. The YANG module itself is defined in Section 2.3.
2.1. Data Model Overview
This section provides an overview of the "ietf-keystore" module in
terms of its features, typedefs, groupings, and protocol-accessible
nodes.
2.1.1. Features
The following diagram lists all the "feature" statements defined in
the "ietf-keystore" module:
Watsen Expires 2 September 2024 [Page 7]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
Features:
+-- central-keystore-supported
+-- inline-definitions-supported
+-- asymmetric-keys
+-- symmetric-keys
The diagram above uses syntax that is similar to but not defined in
[RFC8340].
2.1.2. Typedefs
The following diagram lists the "typedef" statements defined in the
"ietf-keystore" module:
Typedefs:
leafref
+-- central-symmetric-key-ref
+-- central-asymmetric-key-ref
The diagram above uses syntax that is similar to but not defined in
[RFC8340].
Comments:
* All the typedefs defined in the "ietf-keystore" module extend the
base "leafref" type defined in [RFC7950].
* The leafrefs refer to symmetric and asymmetric keys in the central
keystore, when this module is implemented.
* These typedefs are provided as an aid to consuming modules that
import the "ietf-keystore" module.
2.1.3. Groupings
The "ietf-keystore" module defines the following "grouping"
statements:
* encrypted-by-grouping
* central-asymmetric-key-certificate-ref-grouping
* inline-or-keystore-symmetric-key-grouping
* inline-or-keystore-asymmetric-key-grouping
* inline-or-keystore-asymmetric-key-with-certs-grouping
* inline-or-keystore-end-entity-cert-with-key-grouping
* keystore-grouping
Each of these groupings are presented in the following subsections.
Watsen Expires 2 September 2024 [Page 8]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
2.1.3.1. The "encrypted-by-grouping" Grouping
The following tree diagram [RFC8340] illustrates the "encrypted-by-
grouping" grouping:
grouping encrypted-by-grouping:
+-- (encrypted-by)
+--:(central-symmetric-key-ref)
| {central-keystore-supported,symmetric-keys}?
| +-- symmetric-key-ref? ks:central-symmetric-key-ref
+--:(central-asymmetric-key-ref)
{central-keystore-supported,asymmetric-keys}?
+-- asymmetric-key-ref? ks:central-asymmetric-key-ref
Comments:
* This grouping defines a "choice" statement with options to
reference either a symmetric or an asymmetric key configured in
the keystore.
* This grouping is usable only when the keystore module is
implemented. Servers defining custom keystore locations MUST
augment in alternate "encrypted-by" references to the alternate
locations.
2.1.3.2. The "central-asymmetric-key-certificate-ref-grouping" Grouping
The following tree diagram [RFC8340] illustrates the "central-
asymmetric-key-certificate-ref-grouping" grouping:
grouping central-asymmetric-key-certificate-ref-grouping:
+-- asymmetric-key? ks:central-asymmetric-key-ref
| {central-keystore-supported,asymmetric-keys}?
+-- certificate? leafref
Comments:
* This grouping defines a reference to a certificate in two parts:
the first being the name of the asymmetric key the certificate is
associated with, and the second being the name of the certificate
itself.
* This grouping is usable only when the keystore module is
implemented. Servers defining custom keystore locations can
define an alternate grouping for references to the alternate
locations.
Watsen Expires 2 September 2024 [Page 9]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
2.1.3.3. The "inline-or-keystore-symmetric-key-grouping" Grouping
The following tree diagram [RFC8340] illustrates the "inline-or-
keystore-symmetric-key-grouping" grouping:
grouping inline-or-keystore-symmetric-key-grouping:
+-- (inline-or-keystore)
+--:(inline) {inline-definitions-supported}?
| +-- inline-definition
| +---u ct:symmetric-key-grouping
+--:(central-keystore)
{central-keystore-supported,symmetric-keys}?
+-- central-keystore-reference?
ks:central-symmetric-key-ref
Comments:
* The "inline-or-keystore-symmetric-key-grouping" grouping is
provided solely as convenience to consuming modules that wish to
offer an option for whether a symmetric key is defined inline or
as a reference to a symmetric key in the keystore.
* A "choice" statement is used to expose the various options. Each
option is enabled by a "feature" statement. Additional "case"
statements MAY be augmented in if, e.g., there is a need to
reference a symmetric key in an alternate location.
* For the "inline-definition" option, the definition uses the
"symmetric-key-grouping" grouping discussed in Section 2.1.4.3 of
[I-D.ietf-netconf-crypto-types].
* For the "central-keystore" option, the "central-keystore-
reference" is an instance of the "symmetric-key-ref" discussed in
Section 2.1.2.
2.1.3.4. The "inline-or-keystore-asymmetric-key-grouping" Grouping
The following tree diagram [RFC8340] illustrates the "inline-or-
keystore-asymmetric-key-grouping" grouping:
Watsen Expires 2 September 2024 [Page 10]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
grouping inline-or-keystore-asymmetric-key-grouping:
+-- (inline-or-keystore)
+--:(inline) {inline-definitions-supported}?
| +-- inline-definition
| +---u ct:asymmetric-key-pair-grouping
+--:(central-keystore)
{central-keystore-supported,asymmetric-keys}?
+-- central-keystore-reference?
ks:central-asymmetric-key-ref
Comments:
* The "inline-or-keystore-asymmetric-key-grouping" grouping is
provided solely as convenience to consuming modules that wish to
offer an option for whether an asymmetric key is defined inline or
as a reference to an asymmetric key in the keystore.
* A "choice" statement is used to expose the various options. Each
option is enabled by a "feature" statement. Additional "case"
statements MAY be augmented in if, e.g., there is a need to
reference an asymmetric key in an alternate location.
* For the "inline-definition" option, the definition uses the
"asymmetric-key-pair-grouping" grouping discussed in
Section 2.1.4.6 of [I-D.ietf-netconf-crypto-types].
* For the "central-keystore" option, the "central-keystore-
reference" is an instance of the "asymmetric-key-ref" typedef
discussed in Section 2.1.2.
2.1.3.5. The "inline-or-keystore-asymmetric-key-with-certs-grouping"
Grouping
The following tree diagram [RFC8340] illustrates the "inline-or-
keystore-asymmetric-key-with-certs-grouping" grouping:
grouping inline-or-keystore-asymmetric-key-with-certs-grouping:
+-- (inline-or-keystore)
+--:(inline) {inline-definitions-supported}?
| +-- inline-definition
| +---u ct:asymmetric-key-pair-with-certs-grouping
+--:(central-keystore)
{central-keystore-supported,asymmetric-keys}?
+-- central-keystore-reference?
ks:central-asymmetric-key-ref
Comments:
Watsen Expires 2 September 2024 [Page 11]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
* The "inline-or-keystore-asymmetric-key-with-certs-grouping"
grouping is provided solely as convenience to consuming modules
that wish to offer an option for whether an asymmetric key is
defined inline or as a reference to an asymmetric key in the
keystore.
* A "choice" statement is used to expose the various options. Each
option is enabled by a "feature" statement. Additional "case"
statements MAY be augmented in if, e.g., there is a need to
reference an asymmetric key in an alternate location.
* For the "inline-definition" option, the definition uses the
"asymmetric-key-pair-with-certs-grouping" grouping discussed in
Section 2.1.4.12 of [I-D.ietf-netconf-crypto-types].
* For the "central-keystore" option, the "central-keystore-
reference" is an instance of the "asymmetric-key-ref" typedef
discussed in Section 2.1.2.
2.1.3.6. The "inline-or-keystore-end-entity-cert-with-key-grouping"
Grouping
The following tree diagram [RFC8340] illustrates the "inline-or-
keystore-end-entity-cert-with-key-grouping" grouping:
grouping inline-or-keystore-end-entity-cert-with-key-grouping:
+-- (inline-or-keystore)
+--:(inline) {inline-definitions-supported}?
| +-- inline-definition
| +---u ct:asymmetric-key-pair-with-cert-grouping
+--:(central-keystore)
{central-keystore-supported,asymmetric-keys}?
+-- central-keystore-reference
+---u central-asymmetric-key-certificate-ref-grouping
Comments:
* The "inline-or-keystore-end-entity-cert-with-key-grouping"
grouping is provided solely as convenience to consuming modules
that wish to offer an option for whether a symmetric key is
defined inline or as a reference to a symmetric key in the
keystore.
* A "choice" statement is used to expose the various options. Each
option is enabled by a "feature" statement. Additional "case"
statements MAY be augmented in if, e.g., there is a need to
reference a symmetric key in an alternate location.
Watsen Expires 2 September 2024 [Page 12]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
* For the "inline-definition" option, the definition uses the
"asymmetric-key-pair-with-certs-grouping" grouping discussed in
Section 2.1.4.12 of [I-D.ietf-netconf-crypto-types].
* For the "central-keystore" option, the "central-keystore-
reference" uses the "central-asymmetric-key-certificate-ref-
grouping" grouping discussed in Section 2.1.3.2.
2.1.3.7. The "keystore-grouping" Grouping
The following tree diagram [RFC8340] illustrates the "keystore-
grouping" grouping:
grouping keystore-grouping:
+-- asymmetric-keys {asymmetric-keys}?
| +-- asymmetric-key* [name]
| +-- name? string
| +---u ct:asymmetric-key-pair-with-certs-grouping
+-- symmetric-keys {symmetric-keys}?
+-- symmetric-key* [name]
+-- name? string
+---u ct:symmetric-key-grouping
Comments:
* The "keystore-grouping" grouping defines a keystore instance as
being composed of symmetric and asymmetric keys. The structure
for the symmetric and asymmetric keys is essentially the same,
being a "list" inside a "container".
* For asymmetric keys, each "asymmetric-key" uses the "asymmetric-
key-pair-with-certs-grouping" grouping discussed in
Section 2.1.4.12 of [I-D.ietf-netconf-crypto-types].
* For symmetric keys, each "symmetric-key" uses the "symmetric-key-
grouping" grouping discussed in Section 2.1.4.3 of
[I-D.ietf-netconf-crypto-types].
2.1.4. Protocol-accessible Nodes
The following tree diagram [RFC8340] lists all the protocol-
accessible nodes defined in the "ietf-keystore" module, without
expanding the "grouping" statements:
module: ietf-keystore
+--rw keystore {central-keystore-supported}?
+---u keystore-grouping
Watsen Expires 2 September 2024 [Page 13]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
The following tree diagram [RFC8340] lists all the protocol-
accessible nodes defined in the "ietf-keystore" module, with all
"grouping" statements expanded, enabling the keystore's full
structure to be seen:
=============== NOTE: '\' line wrapping per RFC 8792 ================
module: ietf-keystore
+--rw keystore {central-keystore-supported}?
+--rw asymmetric-keys {asymmetric-keys}?
| +--rw asymmetric-key* [name]
| +--rw name string
| +--rw public-key-format? identityref
| +--rw public-key? binary
| +--rw private-key-format? identityref
| +--rw (private-key-type)
| | +--:(cleartext-private-key) {cleartext-private-keys}?
| | | +--rw cleartext-private-key? binary
| | +--:(hidden-private-key) {hidden-private-keys}?
| | | +--rw hidden-private-key? empty
| | +--:(encrypted-private-key) {encrypted-private-keys}?
| | +--rw encrypted-private-key
| | +--rw encrypted-by
| | | +--rw (encrypted-by)
| | | +--:(central-symmetric-key-ref)
| | | | {central-keystore-supported,symme\
tric-keys}?
| | | | +--rw symmetric-key-ref?
| | | | ks:central-symmetric-key-ref
| | | +--:(central-asymmetric-key-ref)
| | | {central-keystore-supported,asymm\
etric-keys}?
| | | +--rw asymmetric-key-ref?
| | | ks:central-asymmetric-key-ref
| | +--rw encrypted-value-format identityref
| | +--rw encrypted-value binary
| +--rw certificates
| | +--rw certificate* [name]
| | +--rw name string
| | +--rw cert-data end-entity-cert-cms
| | +---n certificate-expiration
| | {certificate-expiration-notification}?
| | +-- expiration-date yang:date-and-time
| +---x generate-csr {csr-generation}?
| +---w input
| | +---w csr-format identityref
| | +---w csr-info csr-info
| +--ro output
Watsen Expires 2 September 2024 [Page 14]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
| +--ro (csr-type)
| +--:(p10-csr)
| +--ro p10-csr? p10-csr
+--rw symmetric-keys {symmetric-keys}?
+--rw symmetric-key* [name]
+--rw name string
+--rw key-format? identityref
+--rw (key-type)
+--:(cleartext-symmetric-key)
| +--rw cleartext-symmetric-key? binary
| {cleartext-symmetric-keys}?
+--:(hidden-symmetric-key) {hidden-symmetric-keys}?
| +--rw hidden-symmetric-key? empty
+--:(encrypted-symmetric-key)
{encrypted-symmetric-keys}?
+--rw encrypted-symmetric-key
+--rw encrypted-by
| +--rw (encrypted-by)
| +--:(central-symmetric-key-ref)
| | {central-keystore-supported,symme\
tric-keys}?
| | +--rw symmetric-key-ref?
| | ks:central-symmetric-key-ref
| +--:(central-asymmetric-key-ref)
| {central-keystore-supported,asymm\
etric-keys}?
| +--rw asymmetric-key-ref?
| ks:central-asymmetric-key-ref
+--rw encrypted-value-format identityref
+--rw encrypted-value binary
Comments:
* Protocol-accessible nodes are those nodes that are accessible when
the module is "implemented", as described in Section 5.6.5 of
[RFC7950].
* The protocol-accessible nodes for the "ietf-keystore" module are
instances of the "keystore-grouping" grouping discussed in
Section 2.1.3.7.
* The top-level node "keystore" is additionally constrained by the
feature "central-keystore-supported".
* The "keystore-grouping" grouping is discussed in Section 2.1.3.7.
Watsen Expires 2 September 2024 [Page 15]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
* The reason for why "keystore-grouping" exists separate from the
protocol-accessible nodes definition is so as to enable instances
of the keystore to be instantiated in other locations, as may be
needed or desired by some modules.
2.2. Example Usage
The examples in this section are encoded using XML, such as might be
the case when using the NETCONF protocol. Other encodings MAY be
used, such as JSON when using the RESTCONF protocol.
2.2.1. A Keystore Instance
The following example illustrates keys in <running>. Please see
Section 3 for an example illustrating built-in values in
<operational>.
=============== NOTE: '\' line wrapping per RFC 8792 ================
<keystore
xmlns="urn:ietf:params:xml:ns:yang:ietf-keystore"
xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-crypto-types">
<symmetric-keys>
<symmetric-key>
<name>cleartext-symmetric-key</name>
<key-format>ct:octet-string-key-format</key-format>
<cleartext-symmetric-key>BASE64VALUE=</cleartext-symmetric-\
key>
</symmetric-key>
<symmetric-key>
<name>hidden-symmetric-key</name>
<hidden-symmetric-key/>
</symmetric-key>
<symmetric-key>
<name>encrypted-symmetric-key</name>
<key-format>ct:one-symmetric-key-format</key-format>
<encrypted-symmetric-key>
<encrypted-by>
<asymmetric-key-ref>hidden-asymmetric-key</asymmetric-k\
ey-ref>
</encrypted-by>
<encrypted-value-format>ct:cms-enveloped-data-format</enc\
rypted-value-format>
<encrypted-value>BASE64VALUE=</encrypted-value>
</encrypted-symmetric-key>
</symmetric-key>
</symmetric-keys>
Watsen Expires 2 September 2024 [Page 16]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
<asymmetric-keys>
<asymmetric-key>
<name>ssh-rsa-key</name>
<private-key-format>ct:rsa-private-key-format</private-key-\
format>
<cleartext-private-key>BASE64VALUE=</cleartext-private-key>
</asymmetric-key>
<asymmetric-key>
<name>ssh-rsa-key-with-cert</name>
<private-key-format>ct:rsa-private-key-format</private-key-\
format>
<cleartext-private-key>BASE64VALUE=</cleartext-private-key>
<certificates>
<certificate>
<name>ex-rsa-cert2</name>
<cert-data>BASE64VALUE=</cert-data>
</certificate>
</certificates>
</asymmetric-key>
<asymmetric-key>
<name>raw-private-key</name>
<private-key-format>ct:rsa-private-key-format</private-key-\
format>
<cleartext-private-key>BASE64VALUE=</cleartext-private-key>
</asymmetric-key>
<asymmetric-key>
<name>rsa-asymmetric-key</name>
<private-key-format>ct:rsa-private-key-format</private-key-\
format>
<cleartext-private-key>BASE64VALUE=</cleartext-private-key>
<certificates>
<certificate>
<name>ex-rsa-cert</name>
<cert-data>BASE64VALUE=</cert-data>
</certificate>
</certificates>
</asymmetric-key>
<asymmetric-key>
<name>ec-asymmetric-key</name>
<private-key-format>ct:ec-private-key-format</private-key-f\
ormat>
<cleartext-private-key>BASE64VALUE=</cleartext-private-key>
<certificates>
<certificate>
<name>ex-ec-cert</name>
<cert-data>BASE64VALUE=</cert-data>
</certificate>
</certificates>
Watsen Expires 2 September 2024 [Page 17]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
</asymmetric-key>
<asymmetric-key>
<name>hidden-asymmetric-key</name>
<public-key-format>ct:subject-public-key-info-format</publi\
c-key-format>
<public-key>BASE64VALUE=</public-key>
<hidden-private-key/>
<certificates>
<certificate>
<name>builtin-idevid-cert</name>
<cert-data>BASE64VALUE=</cert-data>
</certificate>
<certificate>
<name>my-ldevid-cert</name>
<cert-data>BASE64VALUE=</cert-data>
</certificate>
</certificates>
</asymmetric-key>
<asymmetric-key>
<name>encrypted-asymmetric-key</name>
<private-key-format>ct:one-asymmetric-key-format</private-k\
ey-format>
<encrypted-private-key>
<encrypted-by>
<symmetric-key-ref>encrypted-symmetric-key</symmetric-k\
ey-ref>
</encrypted-by>
<encrypted-value-format>ct:cms-encrypted-data-format</enc\
rypted-value-format>
<encrypted-value>BASE64VALUE=</encrypted-value>
</encrypted-private-key>
</asymmetric-key>
</asymmetric-keys>
</keystore>
2.2.2. A Certificate Expiration Notification
The following example illustrates a "certificate-expiration"
notification for a certificate associated with an asymmetric key
configured in the keystore.
Watsen Expires 2 September 2024 [Page 18]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
=============== NOTE: '\' line wrapping per RFC 8792 ================
<notification
xmlns="urn:ietf:params:xml:ns:netconf:notification:1.0">
<eventTime>2018-05-25T00:01:00Z</eventTime>
<keystore xmlns="urn:ietf:params:xml:ns:yang:ietf-keystore">
<asymmetric-keys>
<asymmetric-key>
<name>hidden-asymmetric-key</name>
<certificates>
<certificate>
<name>my-ldevid-cert</name>
<certificate-expiration>
<expiration-date>2018-08-05T14:18:53-05:00</expiration\
-date>
</certificate-expiration>
</certificate>
</certificates>
</asymmetric-key>
</asymmetric-keys>
</keystore>
</notification>
2.2.3. The "Local or Keystore" Groupings
This section illustrates the various "inline-or-keystore" groupings
defined in the "ietf-keystore" module, specifically the "inline-or-
keystore-symmetric-key-grouping" (Section 2.1.3.3), "inline-or-
keystore-asymmetric-key-grouping" (Section 2.1.3.4), "inline-or-
keystore-asymmetric-key-with-certs-grouping" (Section 2.1.3.5), and
"inline-or-keystore-end-entity-cert-with-key-grouping"
(Section 2.1.3.6) groupings.
These examples assume the existence of an example module called "ex-
keystore-usage" having the namespace "https://example.com/ns/example-
keystore-usage".
The ex-keystore-usage module is first presented using tree diagrams
[RFC8340], followed by an instance example illustrating all the
"inline-or-keystore" groupings in use, followed by the YANG module
itself.
2.2.3.1. Tree Diagrams for the "ex-keystore-usage" Module
The following tree diagram illustrates "ex-keystore-usage" without
expanding the "grouping" statements:
Watsen Expires 2 September 2024 [Page 19]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
=============== NOTE: '\' line wrapping per RFC 8792 ================
module: ex-keystore-usage
+--rw keystore-usage
+--rw symmetric-key* [name]
| +--rw name string
| +---u ks:inline-or-keystore-symmetric-key-grouping
+--rw asymmetric-key* [name]
| +--rw name string
| +---u ks:inline-or-keystore-asymmetric-key-grouping
+--rw asymmetric-key-with-certs* [name]
| +--rw name
| | string
| +---u ks:inline-or-keystore-asymmetric-key-with-certs-groupi\
ng
+--rw end-entity-cert-with-key* [name]
+--rw name
| string
+---u ks:inline-or-keystore-end-entity-cert-with-key-grouping
The following tree diagram illustrates the "ex-keystore-usage"
module, with all "grouping" statements expanded, enabling the usage's
full structure to be seen:
=============== NOTE: '\' line wrapping per RFC 8792 ================
module: ex-keystore-usage
+--rw keystore-usage
+--rw symmetric-key* [name]
| +--rw name string
| +--rw (inline-or-keystore)
| +--:(inline) {inline-definitions-supported}?
| | +--rw inline-definition
| | +--rw key-format? identityref
| | +--rw (key-type)
| | +--:(cleartext-symmetric-key)
| | | +--rw cleartext-symmetric-key? binary
| | | {cleartext-symmetric-keys}?
| | +--:(hidden-symmetric-key)
| | | {hidden-symmetric-keys}?
| | | +--rw hidden-symmetric-key? empty
| | +--:(encrypted-symmetric-key)
| | {encrypted-symmetric-keys}?
| | +--rw encrypted-symmetric-key
| | +--rw encrypted-by
| | +--rw encrypted-value-format identityref
| | +--rw encrypted-value binary
| +--:(central-keystore)
Watsen Expires 2 September 2024 [Page 20]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
| {central-keystore-supported,symmetric-keys}?
| +--rw central-keystore-reference?
| ks:central-symmetric-key-ref
+--rw asymmetric-key* [name]
| +--rw name string
| +--rw (inline-or-keystore)
| +--:(inline) {inline-definitions-supported}?
| | +--rw inline-definition
| | +--rw public-key-format? identityref
| | +--rw public-key? binary
| | +--rw private-key-format? identityref
| | +--rw (private-key-type)
| | +--:(cleartext-private-key)
| | | {cleartext-private-keys}?
| | | +--rw cleartext-private-key? binary
| | +--:(hidden-private-key) {hidden-private-keys}?
| | | +--rw hidden-private-key? empty
| | +--:(encrypted-private-key)
| | {encrypted-private-keys}?
| | +--rw encrypted-private-key
| | +--rw encrypted-by
| | +--rw encrypted-value-format identityref
| | +--rw encrypted-value binary
| +--:(central-keystore)
| {central-keystore-supported,asymmetric-keys}?
| +--rw central-keystore-reference?
| ks:central-asymmetric-key-ref
+--rw asymmetric-key-with-certs* [name]
| +--rw name string
| +--rw (inline-or-keystore)
| +--:(inline) {inline-definitions-supported}?
| | +--rw inline-definition
| | +--rw public-key-format? identityref
| | +--rw public-key? binary
| | +--rw private-key-format? identityref
| | +--rw (private-key-type)
| | | +--:(cleartext-private-key)
| | | | {cleartext-private-keys}?
| | | | +--rw cleartext-private-key? binary
| | | +--:(hidden-private-key) {hidden-private-keys}?
| | | | +--rw hidden-private-key? empty
| | | +--:(encrypted-private-key)
| | | {encrypted-private-keys}?
| | | +--rw encrypted-private-key
| | | +--rw encrypted-by
| | | +--rw encrypted-value-format identityref
| | | +--rw encrypted-value binary
| | +--rw certificates
Watsen Expires 2 September 2024 [Page 21]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
| | | +--rw certificate* [name]
| | | +--rw name string
| | | +--rw cert-data
| | | | end-entity-cert-cms
| | | +---n certificate-expiration
| | | {certificate-expiration-notification}?
| | | +-- expiration-date yang:date-and-time
| | +---x generate-csr {csr-generation}?
| | +---w input
| | | +---w csr-format identityref
| | | +---w csr-info csr-info
| | +--ro output
| | +--ro (csr-type)
| | +--:(p10-csr)
| | +--ro p10-csr? p10-csr
| +--:(central-keystore)
| {central-keystore-supported,asymmetric-keys}?
| +--rw central-keystore-reference?
| ks:central-asymmetric-key-ref
+--rw end-entity-cert-with-key* [name]
+--rw name string
+--rw (inline-or-keystore)
+--:(inline) {inline-definitions-supported}?
| +--rw inline-definition
| +--rw public-key-format? identityref
| +--rw public-key? binary
| +--rw private-key-format? identityref
| +--rw (private-key-type)
| | +--:(cleartext-private-key)
| | | {cleartext-private-keys}?
| | | +--rw cleartext-private-key? binary
| | +--:(hidden-private-key) {hidden-private-keys}?
| | | +--rw hidden-private-key? empty
| | +--:(encrypted-private-key)
| | {encrypted-private-keys}?
| | +--rw encrypted-private-key
| | +--rw encrypted-by
| | +--rw encrypted-value-format identityref
| | +--rw encrypted-value binary
| +--rw cert-data?
| | end-entity-cert-cms
| +---n certificate-expiration
| | {certificate-expiration-notification}?
| | +-- expiration-date yang:date-and-time
| +---x generate-csr {csr-generation}?
| +---w input
| | +---w csr-format identityref
| | +---w csr-info csr-info
Watsen Expires 2 September 2024 [Page 22]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
| +--ro output
| +--ro (csr-type)
| +--:(p10-csr)
| +--ro p10-csr? p10-csr
+--:(central-keystore)
{central-keystore-supported,asymmetric-keys}?
+--rw central-keystore-reference
+--rw asymmetric-key?
| ks:central-asymmetric-key-ref
| {central-keystore-supported,asymmetric-keys\
}?
+--rw certificate? leafref
2.2.3.2. Example Usage for the "ex-keystore-usage" Module
The following example provides two equivalent instances of each
grouping, the first being a reference to a keystore and the second
being inlined. The instance having a reference to a keystore is
consistent with the keystore defined in Section 2.2.1. The two
instances are equivalent, as the inlined instance example contains
the same values defined by the keystore instance referenced by its
sibling example.
=============== NOTE: '\' line wrapping per RFC 8792 ================
<keystore-usage
xmlns="https://example.com/ns/example-keystore-usage"
xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-crypto-types">
<!-- The following two equivalent examples illustrate the -->
<!-- "inline-or-keystore-symmetric-key-grouping" grouping: -->
<symmetric-key>
<name>example 1a</name>
<central-keystore-reference>cleartext-symmetric-key</central-key\
store-reference>
</symmetric-key>
<symmetric-key>
<name>example 1b</name>
<inline-definition>
<key-format>ct:octet-string-key-format</key-format>
<cleartext-symmetric-key>BASE64VALUE=</cleartext-symmetric-key>
</inline-definition>
</symmetric-key>
<!-- The following two equivalent examples illustrate the -->
Watsen Expires 2 September 2024 [Page 23]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
<!-- "inline-or-keystore-asymmetric-key-grouping" grouping: -->
<asymmetric-key>
<name>example 2a</name>
<central-keystore-reference>rsa-asymmetric-key</central-keystore\
-reference>
</asymmetric-key>
<asymmetric-key>
<name>example 2b</name>
<inline-definition>
<public-key-format>ct:subject-public-key-info-format</public-k\
ey-format>
<public-key>BASE64VALUE=</public-key>
<private-key-format>ct:rsa-private-key-format</private-key-for\
mat>
<cleartext-private-key>BASE64VALUE=</cleartext-private-key>
</inline-definition>
</asymmetric-key>
<!-- the following two equivalent examples illustrate -->
<!-- "inline-or-keystore-asymmetric-key-with-certs-grouping": -->
<asymmetric-key-with-certs>
<name>example 3a</name>
<central-keystore-reference>rsa-asymmetric-key</central-keystore\
-reference>
</asymmetric-key-with-certs>
<asymmetric-key-with-certs>
<name>example 3b</name>
<inline-definition>
<public-key-format>ct:subject-public-key-info-format</public-k\
ey-format>
<public-key>BASE64VALUE=</public-key>
<private-key-format>ct:rsa-private-key-format</private-key-for\
mat>
<cleartext-private-key>BASE64VALUE=</cleartext-private-key>
<certificates>
<certificate>
<name>a locally-defined cert</name>
<cert-data>BASE64VALUE=</cert-data>
</certificate>
</certificates>
</inline-definition>
</asymmetric-key-with-certs>
Watsen Expires 2 September 2024 [Page 24]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
<!-- The following two equivalent examples illustrate -->
<!-- "inline-or-keystore-end-entity-cert-with-key-grouping": -->
<end-entity-cert-with-key>
<name>example 4a</name>
<central-keystore-reference>
<asymmetric-key>rsa-asymmetric-key</asymmetric-key>
<certificate>ex-rsa-cert</certificate>
</central-keystore-reference>
</end-entity-cert-with-key>
<end-entity-cert-with-key>
<name>example 4b</name>
<inline-definition>
<public-key-format>ct:subject-public-key-info-format</public-k\
ey-format>
<public-key>BASE64VALUE=</public-key>
<private-key-format>ct:rsa-private-key-format</private-key-for\
mat>
<cleartext-private-key>BASE64VALUE=</cleartext-private-key>
<cert-data>BASE64VALUE=</cert-data>
</inline-definition>
</end-entity-cert-with-key>
</keystore-usage>
2.2.3.3. The "ex-keystore-usage" YANG Module
Following is the "ex-keystore-usage" module's YANG definition:
module ex-keystore-usage {
yang-version 1.1;
namespace "https://example.com/ns/example-keystore-usage";
prefix ex-keystore-usage;
import ietf-keystore {
prefix ks;
reference
"RFC CCCC: A YANG Data Model for a Keystore";
}
organization
"Example Corporation";
contact
"Author: YANG Designer <mailto:yang.designer@example.com>";
description
Watsen Expires 2 September 2024 [Page 25]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
"This example module illustrates notable groupings defined
in the 'ietf-keystore' module.";
revision 2024-03-02 {
description
"Initial version";
reference
"RFC CCCC: A YANG Data Model for a Keystore";
}
container keystore-usage {
description
"An illustration of the various keystore groupings.";
list symmetric-key {
key "name";
leaf name {
type string;
description
"An arbitrary name for this key.";
}
uses ks:inline-or-keystore-symmetric-key-grouping;
description
"An symmetric key that may be configured locally or be a
reference to a symmetric key in the keystore.";
}
list asymmetric-key {
key "name";
leaf name {
type string;
description
"An arbitrary name for this key.";
}
uses ks:inline-or-keystore-asymmetric-key-grouping;
description
"An asymmetric key, with no certs, that may be configured
locally or be a reference to an asymmetric key in the
keystore. The intent is to reference just the asymmetric
key, not any certificates that may also be associated
with the asymmetric key.";
}
list asymmetric-key-with-certs {
key "name";
leaf name {
type string;
description
"An arbitrary name for this key.";
}
uses ks:inline-or-keystore-asymmetric-key-with-certs-grouping;
Watsen Expires 2 September 2024 [Page 26]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
description
"An asymmetric key and its associated certs, that may be
configured locally or be a reference to an asymmetric key
(and its associated certs) in the keystore.";
}
list end-entity-cert-with-key {
key "name";
leaf name {
type string;
description
"An arbitrary name for this key.";
}
uses ks:inline-or-keystore-end-entity-cert-with-key-grouping;
description
"An end-entity certificate and its associated asymmetric
key, that may be configured locally or be a reference
to another certificate (and its associated asymmetric
key) in the keystore.";
}
}
}
2.3. YANG Module
This YANG module has normative references to [RFC8341] and
[I-D.ietf-netconf-crypto-types].
<CODE BEGINS> file "ietf-keystore@2024-03-02.yang"
module ietf-keystore {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-keystore";
prefix ks;
import ietf-netconf-acm {
prefix nacm;
reference
"RFC 8341: Network Configuration Access Control Model";
}
import ietf-crypto-types {
prefix ct;
reference
"RFC AAAA: YANG Data Types and Groupings for Cryptography";
}
organization
"IETF NETCONF (Network Configuration) Working Group";
Watsen Expires 2 September 2024 [Page 27]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
contact
"WG Web: https://datatracker.ietf.org/wg/netconf
WG List: NETCONF WG list <mailto:netconf@ietf.org>
Author: Kent Watsen <mailto:kent+ietf@watsen.net>";
description
"This module defines a 'keystore' to centralize management
of security credentials.
Copyright (c) 2024 IETF Trust and the persons identified
as authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with
or without modification, is permitted pursuant to, and
subject to the license terms contained in, the Revised
BSD License set forth in Section 4.c of the IETF Trust's
Legal Provisions Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC CCCC
(https://www.rfc-editor.org/info/rfcCCCC); see the RFC
itself for full legal notices.
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 (RFC 2119)
(RFC 8174) when, and only when, they appear in all
capitals, as shown here.";
revision 2024-03-02 {
description
"Initial version";
reference
"RFC CCCC: A YANG Data Model for a Keystore";
}
/****************/
/* Features */
/****************/
feature central-keystore-supported {
description
"The 'central-keystore-supported' feature indicates that
the server supports the central keystore (i.e., fully
implements the 'ietf-keystore' module).";
}
Watsen Expires 2 September 2024 [Page 28]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
feature inline-definitions-supported {
description
"The 'inline-definitions-supported' feature indicates that
the server supports locally-defined keys.";
}
feature asymmetric-keys {
description
"The 'asymmetric-keys' feature indicates that the server
implements the /keystore/asymmetric-keys subtree.";
}
feature symmetric-keys {
description
"The 'symmetric-keys' feature indicates that the server
implements the /keystore/symmetric-keys subtree.";
}
/****************/
/* Typedefs */
/****************/
typedef central-symmetric-key-ref {
type leafref {
path "/ks:keystore/ks:symmetric-keys/ks:symmetric-key"
+ "/ks:name";
}
description
"This typedef enables modules to easily define a reference
to a symmetric key stored in the central keystore.";
}
typedef central-asymmetric-key-ref {
type leafref {
path "/ks:keystore/ks:asymmetric-keys/ks:asymmetric-key"
+ "/ks:name";
}
description
"This typedef enables modules to easily define a reference
to an asymmetric key stored in the central keystore.";
}
/*****************/
/* Groupings */
/*****************/
grouping encrypted-by-grouping {
Watsen Expires 2 September 2024 [Page 29]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
description
"A grouping that defines a 'choice' statement that can be
augmented into the 'encrypted-by' node, present in the
'symmetric-key-grouping' and 'asymmetric-key-pair-grouping'
groupings defined in RFC AAAA, enabling references to keys
in the central keystore.";
choice encrypted-by {
nacm:default-deny-write;
mandatory true;
description
"A choice amongst other symmetric or asymmetric keys.";
case central-symmetric-key-ref {
if-feature "central-keystore-supported";
if-feature "symmetric-keys";
leaf symmetric-key-ref {
type ks:central-symmetric-key-ref;
description
"Identifies the symmetric key used to encrypt the
associated key.";
}
}
case central-asymmetric-key-ref {
if-feature "central-keystore-supported";
if-feature "asymmetric-keys";
leaf asymmetric-key-ref {
type ks:central-asymmetric-key-ref;
description
"Identifies the asymmetric key whose public key
encrypted the associated key.";
}
}
}
}
// *-ref groupings
grouping central-asymmetric-key-certificate-ref-grouping {
description
"Grouping for the reference to a certificate associated
with an asymmetric key stored in the central keystore.";
leaf asymmetric-key {
nacm:default-deny-write;
if-feature "central-keystore-supported";
if-feature "asymmetric-keys";
type ks:central-asymmetric-key-ref;
must '../certificate';
description
"A reference to an asymmetric key in the keystore.";
Watsen Expires 2 September 2024 [Page 30]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
}
leaf certificate {
nacm:default-deny-write;
type leafref {
path "/ks:keystore/ks:asymmetric-keys/ks:asymmetric-key"
+ "[ks:name = current()/../asymmetric-key]/"
+ "ks:certificates/ks:certificate/ks:name";
}
must '../asymmetric-key';
description
"A reference to a specific certificate of the
asymmetric key in the keystore.";
}
}
// inline-or-keystore-* groupings
grouping inline-or-keystore-symmetric-key-grouping {
description
"A grouping for the configuration of a symmetric key. The
symmetric key may be defined inline or as a reference to
a symmetric key stored in the central keystore.
Servers that wish to define alternate keystore locations
SHOULD augment in custom 'case' statements enabling
references to those alternate keystore locations.";
choice inline-or-keystore {
nacm:default-deny-write;
mandatory true;
description
"A choice between an inlined definition and a definition
that exists in the keystore.";
case inline {
if-feature "inline-definitions-supported";
container inline-definition {
description
"Container to hold the local key definition.";
uses ct:symmetric-key-grouping;
}
}
case central-keystore {
if-feature "central-keystore-supported";
if-feature "symmetric-keys";
leaf central-keystore-reference {
type ks:central-symmetric-key-ref;
description
"A reference to an symmetric key that exists in
the central keystore.";
Watsen Expires 2 September 2024 [Page 31]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
}
}
}
}
grouping inline-or-keystore-asymmetric-key-grouping {
description
"A grouping for the configuration of an asymmetric key. The
asymmetric key may be defined inline or as a reference to
an asymmetric key stored in the central keystore.
Servers that wish to define alternate keystore locations
SHOULD augment in custom 'case' statements enabling
references to those alternate keystore locations.";
choice inline-or-keystore {
nacm:default-deny-write;
mandatory true;
description
"A choice between an inlined definition and a definition
that exists in the keystore.";
case inline {
if-feature "inline-definitions-supported";
container inline-definition {
description
"Container to hold the local key definition.";
uses ct:asymmetric-key-pair-grouping;
}
}
case central-keystore {
if-feature "central-keystore-supported";
if-feature "asymmetric-keys";
leaf central-keystore-reference {
type ks:central-asymmetric-key-ref;
description
"A reference to an asymmetric key that exists in
the central keystore. The intent is to reference
just the asymmetric key without any regard for
any certificates that may be associated with it.";
}
}
}
}
grouping inline-or-keystore-asymmetric-key-with-certs-grouping {
description
"A grouping for the configuration of an asymmetric key and
its associated certificates. The asymmetric key and its
associated certificates may be defined inline or as a
Watsen Expires 2 September 2024 [Page 32]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
reference to an asymmetric key (and its associated
certificates) in the central keystore.
Servers that wish to define alternate keystore locations
SHOULD augment in custom 'case' statements enabling
references to those alternate keystore locations.";
choice inline-or-keystore {
nacm:default-deny-write;
mandatory true;
description
"A choice between an inlined definition and a definition
that exists in the keystore.";
case inline {
if-feature "inline-definitions-supported";
container inline-definition {
description
"Container to hold the local key definition.";
uses ct:asymmetric-key-pair-with-certs-grouping;
}
}
case central-keystore {
if-feature "central-keystore-supported";
if-feature "asymmetric-keys";
leaf central-keystore-reference {
type ks:central-asymmetric-key-ref;
description
"A reference to an asymmetric-key (and all of its
associated certificates) in the keystore, when
this module is implemented.";
}
}
}
}
grouping inline-or-keystore-end-entity-cert-with-key-grouping {
description
"A grouping for the configuration of an asymmetric key and
its associated end-entity certificate. The asymmetric key
and its associated end-entity certificate may be defined
inline or as a reference to an asymmetric key (and its
associated end-entity certificate) in the central keystore.
Servers that wish to define alternate keystore locations
SHOULD augment in custom 'case' statements enabling
references to those alternate keystore locations.";
choice inline-or-keystore {
nacm:default-deny-write;
mandatory true;
Watsen Expires 2 September 2024 [Page 33]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
description
"A choice between an inlined definition and a definition
that exists in the keystore.";
case inline {
if-feature "inline-definitions-supported";
container inline-definition {
description
"Container to hold the local key definition.";
uses ct:asymmetric-key-pair-with-cert-grouping;
}
}
case central-keystore {
if-feature "central-keystore-supported";
if-feature "asymmetric-keys";
container central-keystore-reference {
uses central-asymmetric-key-certificate-ref-grouping;
description
"A reference to a specific certificate associated with
an asymmetric key stored in the central keystore.";
}
}
}
}
// the keystore grouping
grouping keystore-grouping {
description
"Grouping definition enables use in other contexts. If ever
done, implementations MUST augment new 'case' statements
into the various inline-or-keystore 'choice' statements to
supply leafrefs to the model-specific location(s).";
container asymmetric-keys {
nacm:default-deny-write;
if-feature "asymmetric-keys";
description
"A list of asymmetric keys.";
list asymmetric-key {
key "name";
description
"An asymmetric key.";
leaf name {
type string;
description
"An arbitrary name for the asymmetric key.";
}
uses ct:asymmetric-key-pair-with-certs-grouping;
}
Watsen Expires 2 September 2024 [Page 34]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
}
container symmetric-keys {
nacm:default-deny-write;
if-feature "symmetric-keys";
description
"A list of symmetric keys.";
list symmetric-key {
key "name";
description
"A symmetric key.";
leaf name {
type string;
description
"An arbitrary name for the symmetric key.";
}
uses ct:symmetric-key-grouping;
}
}
}
/*********************************/
/* Protocol accessible nodes */
/*********************************/
container keystore {
if-feature central-keystore-supported;
description
"A central keystore containing a list of symmetric keys and
a list of asymmetric keys.";
nacm:default-deny-write;
uses keystore-grouping {
augment "symmetric-keys/symmetric-key/key-type/encrypted-"
+ "symmetric-key/encrypted-symmetric-key/encrypted-by" {
description
"Augments in a choice statement enabling the encrypting
key to be any other symmetric or asymmetric key in the
central keystore.";
uses encrypted-by-grouping;
}
augment "asymmetric-keys/asymmetric-key/private-key-type/"
+ "encrypted-private-key/encrypted-private-key/"
+ "encrypted-by" {
description
"Augments in a choice statement enabling the encrypting
key to be any other symmetric or asymmetric key in the
central keystore.";
uses encrypted-by-grouping;
}
Watsen Expires 2 September 2024 [Page 35]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
}
}
}
<CODE ENDS>
3. Support for Built-in Keys
In some implementations, a server may support keys built into the
server. Built-in keys MAY be set during the manufacturing process or
be dynamically generated the first time the server is booted or a
particular service (e.g., SSH) is enabled.
Built-in keys are "hidden" keys expected to be set by a vendor-
specific process. Any ability for operators to set and/or modify
built-in keys is outside the scope of this document.
The primary characteristic of the built-in keys is that they are
provided by the server, as opposed to configuration. As such, they
are present in <operational> (Section 5.3 of [RFC8342]), and <system>
[I-D.ietf-netmod-system-config], if implemented.
The example below illustrates what the keystore in <operational>
might look like for a server in its factory default state. Note that
the built-in keys have the "or:origin" annotation value "or:system".
=============== NOTE: '\' line wrapping per RFC 8792 ================
<keystore xmlns="urn:ietf:params:xml:ns:yang:ietf-keystore"
xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-crypto-types"
xmlns:or="urn:ietf:params:xml:ns:yang:ietf-origin"
or:origin="or:intended">
<asymmetric-keys>
<asymmetric-key or:origin="or:system">
<name>Manufacturer-Generated Hidden Key</name>
<public-key-format>ct:subject-public-key-info-format</public-k\
ey-format>
<public-key>BASE64VALUE=</public-key>
<hidden-private-key/>
<certificates>
<certificate>
<name>Manufacturer-Generated IDevID Cert</name>
<cert-data>BASE64VALUE=</cert-data>
</certificate>
</certificates>
</asymmetric-key>
</asymmetric-keys>
</keystore>
Watsen Expires 2 September 2024 [Page 36]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
The following example illustrates how a single built-in key
definition from the previous example has been propagated to
<running>:
=============== NOTE: '\' line wrapping per RFC 8792 ================
<keystore xmlns="urn:ietf:params:xml:ns:yang:ietf-keystore"
xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-crypto-types">
<asymmetric-keys>
<asymmetric-key>
<name>Manufacturer-Generated Hidden Key</name>
<public-key-format>ct:subject-public-key-info-format</public-k\
ey-format>
<public-key>BASE64VALUE=</public-key>
<hidden-private-key/>
<certificates>
<certificate>
<name>Manufacturer-Generated IDevID Cert</name>
<cert-data>BASE64VALUE=</cert-data>
</certificate>
<certificate>
<name>Deployment-Specific LDevID Cert</name>
<cert-data>BASE64VALUE=</cert-data>
</certificate>
</certificates>
</asymmetric-key>
</asymmetric-keys>
</keystore>
After the above configuration is applied, <operational> should appear
as follows:
Watsen Expires 2 September 2024 [Page 37]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
=============== NOTE: '\' line wrapping per RFC 8792 ================
<keystore xmlns="urn:ietf:params:xml:ns:yang:ietf-keystore"
xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-crypto-types"
xmlns:or="urn:ietf:params:xml:ns:yang:ietf-origin"
or:origin="or:intended">
<asymmetric-keys>
<asymmetric-key or:origin="or:system">
<name>Manufacturer-Generated Hidden Key</name>
<public-key-format>ct:subject-public-key-info-format</public-k\
ey-format>
<public-key>BASE64VALUE=</public-key>
<hidden-private-key/>
<certificates>
<certificate>
<name>Manufacturer-Generated IDevID Cert</name>
<cert-data>BASE64VALUE=</cert-data>
</certificate>
<certificate or:origin="or:intended">
<name>Deployment-Specific LDevID Cert</name>
<cert-data>BASE64VALUE=</cert-data>
</certificate>
</certificates>
</asymmetric-key>
</asymmetric-keys>
</keystore>
4. Encrypting Keys in Configuration
This section describes an approach that enables both the symmetric
and asymmetric keys on a server to be encrypted, such that
traditional backup/restore procedures can be used without concern for
raw key data being compromised when in transit.
4.1. Key Encryption Key
The ability to encrypt configured keys is predicated on the existence
of a "key encryption key" (KEK). There may be any number of KEKs in
a server. A KEK, by its namesake, is a key that is used to encrypt
other keys. A KEK MAY be either a symmetric key or an asymmetric
key.
If a KEK is a symmetric key, then the server MUST provide an API for
administrators to encrypt other keys without needing to know the
symmetric key's value. If the KEK is an asymmetric key, then the
server SHOULD provide an API enabling the encryption of other keys
or, alternatively, assume the administrators can do so themselves
using the asymmetric key's public half.
Watsen Expires 2 September 2024 [Page 38]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
A server MUST possess access to the KEK or an API using the KEK, so
that it can decrypt the other keys in the configuration at runtime.
4.2. Configuring Encrypted Keys
Each time a new key is configured, it SHOULD be encrypted by a KEK.
In "ietf-crypto-types" [I-D.ietf-netconf-crypto-types], the format
for encrypted values is described by identity statements derived from
the "symmetrically-encrypted-value-format" and "asymmetrically-
encrypted-value-format" identity statements.
Implementations SHOULD provide an API that simultaneously generates a
key and encrypts the generated key using a KEK. Thus the cleartext
value of the newly generated key may never be known to the
administrators generating the keys.
In case the server implementation does not provide such an API, then
the generating and encrypting steps MAY be performed outside the
server, e.g., by an administrator with special access control rights
(e.g., an organization's crypto officer).
In either case, the encrypted key can be configured into the keystore
using either the "encrypted-symmetric-key" (for symmetric keys) or
the "encrypted-private-key" (for asymmetric keys) nodes. These two
nodes contain both the encrypted raw key value as well as a reference
to the KEK that encrypted the key.
4.3. Migrating Configuration to Another Server
When a KEK is used to encrypt other keys, migrating the configuration
to another server is only possible if the second server has the same
KEK. How the second server comes to have the same KEK is discussed
in this section.
In some deployments, mechanisms outside the scope of this document
may be used to migrate a KEK from one server to another. That said,
beware that the ability to do so typically entails having access to
the first server but, in some scenarios, the first server may no
longer be operational.
In other deployments, an organization's crypto officer, possessing a
KEK's cleartext value, configures the same KEK on the second server,
presumably as a hidden key or a key protected by access-control, so
that the cleartext value is not disclosed to regular administrators.
However, this approach creates high-coupling to and dependency on the
crypto officers that does not scale in production environments.
Watsen Expires 2 September 2024 [Page 39]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
In order to decouple the crypto officers from the regular
administrators, a special KEK, called the "master key" (MK), may be
used.
A MK is commonly a globally-unique built-in (see Section 3)
asymmetric key. The private raw key value, due to its long lifetime,
is hidden (i.e., "hidden-private-key" in Section 2.1.4.5. of
[I-D.ietf-netconf-crypto-types]). The raw public key value is often
contained in an identity certificate (e.g., IDevID). How to
configure a MK during the manufacturing process is outside the scope
of this document.
Assuming the server has a MK, the MK can be used to encrypt a "shared
KEK", which is then used to encrypt the keys configured by regular
administrators.
With this extra level of indirection, it is possible for a crypto
officer to encrypt the same KEK for a multiplicity of servers offline
using the public key contained in their identity certificates. The
crypto officer can then safely handoff the encrypted KEKs to regular
administrators responsible for server installations, including
migrations.
In order to migrate the configuration from a first server, an
administrator would need to make just a single modification to the
configuration before loading it onto a second server, which is to
replace the encrypted KEK keystore entry from the first server with
the encrypted KEK for the second server. Upon doing this, the
configuration (containing many encrypted keys) can be loaded into the
second server while enabling the second server to decrypt all the
encrypted keys in the configuration.
The following diagram illustrates this idea:
Watsen Expires 2 September 2024 [Page 40]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
+-------------+ +-------------+
| shared KEK | | shared KEK |
|(unencrypted)|-------------------------------> | (encrypted) |
+-------------+ encrypts offline using +-------------+
^ each server's MK |
| |
| |
| possesses \o |
+-------------- |\ |
/ \ shares with |
crypto +--------------------+
officer |
|
|
+----------------------+ | +----------------------+
| server-1 | | | server-2 |
| configuration | | | configuration |
| | | | |
| | | | |
| +----------------+ | | | +----------------+ |
| | MK-1 | | | | | MK-2 | |
| | (hidden) | | | | | (hidden) | |
| +----------------+ | | | +----------------+ |
| ^ | | | ^ |
| | | | | | |
| | | | | | |
| | encrypted | | | | encrypted |
| | by | | | | by |
| | | | | | |
| | | | | | |
| +----------------+ | | | +----------------+ |
| | shared KEK | | | | | shared KEK | |
| | (encrypted) | | v | | (encrypted) | |
| +----------------+ | | +----------------+ |
| ^ | regular | ^ |
| | | admin | | |
| | | | | |
| | encrypted | \o | | encrypted |
| | by | |\ | | by |
| | | / \ | | |
| | | | | |
| +----------------+ |----------------->| +----------------+ |
| | all other keys | | migrate | | all other keys | |
| | (encrypted) | | configuration | | (encrypted) | |
| +----------------+ | | +----------------+ |
| | | |
+----------------------+ +----------------------+
Watsen Expires 2 September 2024 [Page 41]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
5. Security Considerations
5.1. Security of Data at Rest and in Motion
The YANG module defined in this document defines a mechanism called a
"keystore" that intends to protect its contents from unauthorized
disclosure and modification.
In order to satisfy the expectations of a "keystore", it is
RECOMMENDED that implementations ensure that the keystore contents
are encrypted when persisted to non-volatile memory, and ensure that
the keystore contents that have been decrypted in volatile memory are
zeroized when not in use.
5.2. Unconstrained Private Key Usage
This module enables the configuration of private keys without
constraints on their usage, e.g., what operations the key is allowed
to be used for (e.g., signature, decryption, both).
This module also does not constrain the usage of the associated
public keys, other than in the context of a configured certificate
(e.g., an identity certificate), in which case the key usage is
constrained by the certificate.
5.3. Considerations for the "ietf-keystore" YANG Module
This section follows the template defined in Section 3.7.1 of
[RFC8407].
The YANG module defined in this document is designed to be accessed
via YANG based management protocols, such as NETCONF [RFC6241] and
RESTCONF [RFC8040]. Both of these protocols have mandatory-to-
implement secure transport layers (e.g., SSH, TLS) with mutual
authentication.
The Network Access Control Model (NACM) [RFC8341] provides the means
to restrict access for particular users to a pre-configured subset of
all available protocol operations and content.
Please be aware that this YANG module uses groupings from other YANG
modules that define nodes that may be considered sensitive or
vulnerable in network environments. Please review the Security
Considerations for dependent YANG modules for information as to which
nodes may be considered sensitive or vulnerable in network
environments.
Watsen Expires 2 September 2024 [Page 42]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
Some of the readable data nodes defined in this YANG module may be
considered sensitive or vulnerable in some network environments. It
is thus important to control read access (e.g., via get, get-config,
or notification) to these data nodes. The following subtrees and
data nodes have particular sensitivity/vulnerability:
* The "cleartext-symmetric-key" node:
The "cleartext-symmetric-key" node, imported from the
"symmetric-key-grouping" grouping defined in
[I-D.ietf-netconf-crypto-types] is additionally sensitive to
read operations such that, in normal use cases, it should never
be returned to a client. For this reason, the NACM extension
"default-deny-all" was applied to it in
[I-D.ietf-netconf-crypto-types].
* The "cleartext-private-key" node:
The "cleartext-private-key" node defined in the "asymmetric-
key-pair-grouping" grouping defined in
[I-D.ietf-netconf-crypto-types] is additionally sensitive to
read operations such that, in normal use cases, it should never
be returned to a client. For this reason, the NACM extension
"default-deny-all" is applied to it in
[I-D.ietf-netconf-crypto-types].
All the writable data nodes defined by this module, both in the
"grouping" statements as well as the protocol-accessible "keystore"
instance, may be considered sensitive or vulnerable in some network
environments. For instance, any modification to a key or reference
to a key may dramatically alter the implemented security policy. For
this reason, the NACM extension "default-deny-write" has been set for
all data nodes defined in this module.
This module does not define any "rpc" or "action" statements, and
thus the security considerations for such is not provided here.
Built-in key types SHOULD be either hidden and/or encrypted (not
cleartext). If this is not possible, access control mechanisms like
NACM SHOULD be used to limit access to the key's secret data to only
the most trusted authorized clients (e.g., belonging to an
organization’s crypto officer).
6. IANA Considerations
Watsen Expires 2 September 2024 [Page 43]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
6.1. The "IETF XML" Registry
This document registers one URI in the "ns" subregistry of the IETF
XML Registry [RFC3688]. Following the format in [RFC3688], the
following registration is requested:
URI: urn:ietf:params:xml:ns:yang:ietf-keystore
Registrant Contact: The IESG
XML: N/A, the requested URI is an XML namespace.
6.2. The "YANG Module Names" Registry
This document registers one YANG module in the YANG Module Names
registry [RFC6020]. Following the format in [RFC6020], the following
registration is requested:
name: ietf-keystore
namespace: urn:ietf:params:xml:ns:yang:ietf-keystore
prefix: ks
reference: RFC CCCC
7. References
7.1. Normative References
[I-D.ietf-netconf-crypto-types]
Watsen, K., "YANG Data Types and Groupings for
Cryptography", Work in Progress, Internet-Draft, draft-
ietf-netconf-crypto-types-32, 22 February 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
crypto-types-32>.
[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>.
[RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for
the Network Configuration Protocol (NETCONF)", RFC 6020,
DOI 10.17487/RFC6020, October 2010,
<https://www.rfc-editor.org/info/rfc6020>.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/info/rfc7950>.
Watsen Expires 2 September 2024 [Page 44]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
[RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration
Access Control Model", STD 91, RFC 8341,
DOI 10.17487/RFC8341, March 2018,
<https://www.rfc-editor.org/info/rfc8341>.
7.2. Informative References
[I-D.ietf-netconf-http-client-server]
Watsen, K., "YANG Groupings for HTTP Clients and HTTP
Servers", Work in Progress, Internet-Draft, draft-ietf-
netconf-http-client-server-18, 22 February 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
http-client-server-18>.
[I-D.ietf-netconf-keystore]
Watsen, K., "A YANG Data Model for a Keystore and Keystore
Operations", Work in Progress, Internet-Draft, draft-ietf-
netconf-keystore-33, 22 February 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
keystore-33>.
[I-D.ietf-netconf-netconf-client-server]
Watsen, K., "NETCONF Client and Server Models", Work in
Progress, Internet-Draft, draft-ietf-netconf-netconf-
client-server-34, 22 February 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
netconf-client-server-34>.
[I-D.ietf-netconf-restconf-client-server]
Watsen, K., "RESTCONF Client and Server Models", Work in
Progress, Internet-Draft, draft-ietf-netconf-restconf-
client-server-34, 22 February 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
restconf-client-server-34>.
[I-D.ietf-netconf-ssh-client-server]
Watsen, K., "YANG Groupings for SSH Clients and SSH
Servers", Work in Progress, Internet-Draft, draft-ietf-
netconf-ssh-client-server-38, 22 February 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
ssh-client-server-38>.
[I-D.ietf-netconf-tcp-client-server]
Watsen, K. and M. Scharf, "YANG Groupings for TCP Clients
and TCP Servers", Work in Progress, Internet-Draft, draft-
ietf-netconf-tcp-client-server-22, 22 February 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
tcp-client-server-22>.
Watsen Expires 2 September 2024 [Page 45]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
[I-D.ietf-netconf-tls-client-server]
Watsen, K., "YANG Groupings for TLS Clients and TLS
Servers", Work in Progress, Internet-Draft, draft-ietf-
netconf-tls-client-server-39, 22 February 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
tls-client-server-39>.
[I-D.ietf-netconf-trust-anchors]
Watsen, K., "A YANG Data Model for a Truststore", Work in
Progress, Internet-Draft, draft-ietf-netconf-trust-
anchors-26, 22 February 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
trust-anchors-26>.
[I-D.ietf-netmod-system-config]
Ma, Q., Wu, Q., and C. Feng, "System-defined
Configuration", Work in Progress, Internet-Draft, draft-
ietf-netmod-system-config-05, 21 February 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-netmod-
system-config-05>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
and A. Bierman, Ed., "Network Configuration Protocol
(NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
<https://www.rfc-editor.org/info/rfc6241>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/info/rfc8040>.
[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>.
[RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
<https://www.rfc-editor.org/info/rfc8340>.
[RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K.,
and R. Wilton, "Network Management Datastore Architecture
(NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018,
<https://www.rfc-editor.org/info/rfc8342>.
Watsen Expires 2 September 2024 [Page 46]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
[RFC8407] Bierman, A., "Guidelines for Authors and Reviewers of
Documents Containing YANG Data Models", BCP 216, RFC 8407,
DOI 10.17487/RFC8407, October 2018,
<https://www.rfc-editor.org/info/rfc8407>.
[Std-802.1AR-2018]
IEEE SA-Standards Board, "IEEE Standard for Local and
metropolitan area networks - Secure Device Identity",
August 2018,
<https://standards.ieee.org/standard/802_1AR-2018.html>.
Appendix A. Change Log
A.1. 00 to 01
* Replaced the 'certificate-chain' structures with PKCS#7
structures. (Issue #1)
* Added 'private-key' as a configurable data node, and removed the
'generate-private-key' and 'load-private-key' actions. (Issue #2)
* Moved 'user-auth-credentials' to the ietf-ssh-client module.
(Issues #4 and #5)
A.2. 01 to 02
* Added back 'generate-private-key' action.
* Removed 'RESTRICTED' enum from the 'private-key' leaf type.
* Fixed up a few description statements.
A.3. 02 to 03
* Changed draft's title.
* Added missing references.
* Collapsed sections and levels.
* Added RFC 8174 to Requirements Language Section.
* Renamed 'trusted-certificates' to 'pinned-certificates'.
* Changed 'public-key' from config false to config true.
* Switched 'host-key' from OneAsymmetricKey to definition from RFC
4253.
Watsen Expires 2 September 2024 [Page 47]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
A.4. 03 to 04
* Added typedefs around leafrefs to common keystore paths
* Now tree diagrams reference ietf-netmod-yang-tree-diagrams
* Removed Design Considerations section
* Moved key and certificate definitions from data tree to groupings
A.5. 04 to 05
* Removed trust anchors (now in their own draft)
* Added back global keystore structure
* Added groupings enabling keys to either be locally defined or a
reference to the keystore.
A.6. 05 to 06
* Added feature "local-keys-supported"
* Added nacm:default-deny-all and nacm:default-deny-write
* Renamed generate-asymmetric-key to generate-hidden-key
* Added an install-hidden-key action
* Moved actions inside fo the "asymmetric-key" container
* Moved some groupings to draft-ietf-netconf-crypto-types
A.7. 06 to 07
* Removed a "require-instance false"
* Clarified some description statements
* Improved the keystore-usage examples
A.8. 07 to 08
* Added "inline-definition" containers to avoid posibility of the
action/notification statements being under a "case" statement.
* Updated copyright date, boilerplate template, affiliation, folding
algorithm, and reformatted the YANG module.
Watsen Expires 2 September 2024 [Page 48]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
A.9. 08 to 09
* Added a 'description' statement to the 'must' in the /keystore/
asymmetric-key node explaining that the descendant values may
exist in <operational> only, and that implementation MUST assert
that the values are either configured or that they exist in
<operational>.
* Copied above 'must' statement (and description) into the inline-
or-keystore-asymmetric-key-grouping, inline-or-keystore-
asymmetric-key-with-certs-grouping, and inline-or-keystore-end-
entity-cert-with-key-grouping statements.
A.10. 09 to 10
* Updated draft title to match new truststore draft title
* Moved everything under a top-level 'grouping' to enable use in
other contexts.
* Renamed feature from 'local-keys-supported' to 'inline-
definitions-supported' (same name used in truststore)
* Removed the either-all-or-none 'must' expressions for the key's
3-tuple values (since the values are now 'mandatory true' in
crypto-types)
* Example updated to reflect 'mandatory true' change in crypto-types
draft
A.11. 10 to 11
* Replaced typedef asymmetric-key-certificate-ref with grouping
asymmetric-key-certificate-ref-grouping.
* Added feature feature 'key-generation'.
* Cloned groupings symmetric-key-grouping, asymmetric-key-pair-
grouping, asymmetric-key-pair-with-cert-grouping, and asymmetric-
key-pair-with-certs-grouping from crypto-keys, augmenting into
each new case statements for values that have been encrypted by
other keys in the keystore. Refactored keystore model to use
these groupings.
* Added new 'symmetric-keys' lists, as a sibling to the existing
'asymmetric-keys' list.
Watsen Expires 2 September 2024 [Page 49]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
* Added RPCs (not actions) 'generate-symmetric-key' and 'generate-
asymmetric-key' to *return* a (potentially encrypted) key.
A.12. 11 to 12
* Updated to reflect crypto-type's draft using enumerations over
identities.
* Added examples for the 'generate-symmetric-key' and 'generate-
asymmetric-key' RPCs.
* Updated the Introduction section.
A.13. 12 to 13
* Updated examples to incorporate new "key-format" identities.
* Made the two "generate-*-key" RPCs be "action" statements instead.
A.14. 13 to 14
* Updated YANG module and examples to incorporate the new
iana-*-algorithm modules in the crypto-types draft.
A.15. 14 to 15
* Added new "Support for Built-in Keys" section.
* Added 'must' expressions asserting that the 'key-format' leaf
whenever an encrypted key is specified.
* Added inline-or-keystore-symmetric-key-grouping for PSK support.
A.16. 15 to 16
* Moved the generate key actions to ietf-crypt-types as RPCs, which
are augmented by ietf-keystore to support encrypted keys.
Examples updated accordingly.
* Added a SSH certificate-based key (RFC 6187) and a raw private key
to the example instance document (partly so they could be
referenced by examples in the SSH and TLS client/server drafts.
A.17. 16 to 17
* Removed augments to the "generate-symmetric-key" and "generate-
asymmetric-key" groupings.
Watsen Expires 2 September 2024 [Page 50]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
* Removed "generate-symmetric-key" and "generate-asymmetric-key"
examples.
* Removed the "algorithm" nodes from remaining examples.
* Updated the "Support for Built-in Keys" section.
* Added new section "Encrypting Keys in Configuration".
* Added a "Note to Reviewers" note to first page.
A.18. 17 to 18
* Removed dangling/unnecessary ref to RFC 8342.
* r/MUST/SHOULD/ wrt strength of keys being configured over
transports.
* Added an example for the "certificate-expiration" notification.
* Clarified that OS MAY have a multiplicity of underlying keystores
and/or TPMs.
* Clarified expected behavior for "built-in" keys in <operational>
* Clarified the "Migrating Configuration to Another Server" section.
* Expanded "Data Model Overview section(s) [remove "wall" of tree
diagrams].
* Updated the Security Considerations section.
A.19. 18 to 19
* Updated examples to reflect new "cleartext-" prefix in the crypto-
types draft.
A.20. 19 to 20
* Addressed SecDir comments from Magnus Nystroem and Sandra Murphy.
A.21. 20 to 21
* Added a "Unconstrained Private Key Usage" Security Consideration
to address concern raised by SecDir.
Watsen Expires 2 September 2024 [Page 51]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
* (Editorial) Removed the output of "grouping" statements in the
tree diagrams for the "ietf-keystore" and "ex-keystore-usage"
modules.
* Addressed comments raised by YANG Doctor.
A.22. 21 to 22
* Added prefixes to 'path' statements per trust-anchors/issues/1
* Renamed feature "keystore-supported" to "central-keystore-
supported".
* Associated with above, generally moved text to refer to a
"central" keystore.
* Aligned modules with `pyang -f` formatting.
* Fixed nits found by YANG Doctor reviews.
A.23. 22 to 23
* Updated 802.1AR ref to latest version
* Replaced "base64encodedvalue==" with "BASE64VALUE=" in examples.
* Minor editorial nits
A.24. 23 to 24
* Added features "asymmetric-keys" and "symmetric-keys"
* fixup the 'WG Web' and 'WG List' lines in YANG module(s)
* fixup copyright (i.e., s/Simplified/Revised/) in YANG module(s)
* Added Informative reference to ma-netmod-with-system
A.25. 24 to 25
* Added a "term" for "key" (IEEE liaison).
* Clarified draft text to ensure proper use of the "key" term.
(IEEE liaison)
* Added statement that built-in keys SHOULD NOT be cleartext. (IEEE
liaison)
Watsen Expires 2 September 2024 [Page 52]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
* Added "if-feature central-keystore-supported" to top-level
"keystore" container.
A.26. 25 to 26
* Updated per Shepherd reviews impacting the suite of drafts.
A.27. 26 to 27
* Updated per Shepherd reviews impacting the suite of drafts.
A.28. 27 to 28
* Updated per Tom Petch review.
* s/local/inline/ in feature names, grouping names, and node names.
* Removed special handling text for built-in keys
* Updated section on built-in keys to read almost the same as the
section in the trust-anchors draft.
A.29. 28 to 29
* Addresses AD review comments.
* Added note to Editor to fix line foldings.
* Renamed "keystore" to "central keystore" throughout.
* Renamed "encrypted-by-choice-grouping" to "encrypted-by-grouping".
* Removed "public-key-format" and "public-key" nodes from examples.
A.30. 29 to 30
* Addresses Gen-ART review by Reese Enghardt.
* Addresses review by Tom Petch.
A.31. 30 to 31
* Addresses 1st-round of IESG reviews.
A.32. 31 to 33
* Addresses issues found in OpsDir review of the ssh-client-server
draft.
Watsen Expires 2 September 2024 [Page 53]
Internet-Draft A YANG Data Model for a Keystore and Key March 2024
* Renamed Security Considerations section s/Template for/
Considerations for/
* s/defines/presents/ in a few places.
* Add refs to where the 'operational' and 'system' datastores are
defined.
A.33. 33 to 34
* Nothing added. Only bumped for automation...
Acknowledgements
The authors would like to thank the following for lively discussions
on list and in the halls (ordered by first name): Alan Luchuk, Andy
Bierman, Benoit Claise, Bert Wijnen, Balázs Kovács, David Lamparter,
Eric Voit, Éric Vyncke, Francesca Palombini, Ladislav Lhotka, Liang
Xia, Jürgen Schönwälder, Mahesh Jethanandani, Magnus Nyström, Martin
Björklund, Mehmet Ersue, Murray Kucherawy, Paul Wouters, Phil Shafer,
Qin Wu, Radek Krejci, Ramkumar Dhanapal, Reese Enghardt, Reshad
Rahman, Rob Wilton, Roman Danyliw, Sandra Murphy, Sean Turner, Tom
Petch, Warren Kumari, and Zaheduzzaman Sarker.
Author's Address
Kent Watsen
Watsen Networks
Email: kent+ietf@watsen.net
Watsen Expires 2 September 2024 [Page 54]
