YANG Data Types and Groupings for Cryptography
draft-ietf-netconf-crypto-types-21
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Active Internet-Draft (netconf WG)
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Kent Watsen
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2021-09-14
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draft-kwatsen-netconf-crypto-types
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Internet Engineering Task Force (IETF)
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(None)
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draft-ietf-netconf-crypto-types-21.txt:
xym 0.5:
Extracting 'ex-crypto-types-usage'
Getting YANG file name from module name: ex-crypto-types-usage.yang
Extracting 'ietf-crypto-types@2021-09-14.yang'
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ietf-crypto-types@2021-09-14.yang:
pyang 2.5.0: pyang --verbose --ietf -p {libs} {model}:
# module search path: a/www/ietf-ftp/yang/rfcmod/:/a/www/ietf-ftp/yang/draftmod/:/a/www/ietf-ftp/yang/ianamod/:/a/www/ietf-ftp/yang/catalogmod/:.:/a/www/ietf-datatracker/7.38.0/env/share/yang/modules
# read ietf-crypto-types@2021-09-14.yang (CL)
# read /a/www/ietf-datatracker/7.38.0/env/share/yang/modules/ietf/ietf-yang-types.yang
# read /a/www/ietf-ftp/yang/draftmod/ietf-yang-types@2021-07-09.yang
# read /a/www/ietf-datatracker/7.38.0/env/share/yang/modules/ietf/ietf-netconf-acm.yang
# read /a/www/ietf-ftp/yang/rfcmod/ietf-netconf-acm@2018-02-14.yang
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NETCONF Working Group K. Watsen
Internet-Draft Watsen Networks
Intended status: Standards Track 14 September 2021
Expires: 18 March 2022
YANG Data Types and Groupings for Cryptography
draft-ietf-netconf-crypto-types-21
Abstract
This document presents a YANG 1.1 (RFC 7950) module defining
identities, typedefs, and groupings useful to cryptographic
applications.
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 this draft
Artwork in this document contains placeholder values for the date of
publication of this draft. Please apply the following replacement:
* "2021-09-14" --> the publication date of this draft
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/.
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Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 18 March 2022.
Copyright Notice
Copyright (c) 2021 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 Simplified BSD License text
as described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Simplified BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1. Relation to other RFCs . . . . . . . . . . . . . . . . . 3
1.2. Specification Language . . . . . . . . . . . . . . . . . 5
1.3. Adherence to the NMDA . . . . . . . . . . . . . . . . . . 5
1.4. Conventions . . . . . . . . . . . . . . . . . . . . . . . 5
2. The "ietf-crypto-types" Module . . . . . . . . . . . . . . . 5
2.1. Data Model Overview . . . . . . . . . . . . . . . . . . . 5
2.2. Example Usage . . . . . . . . . . . . . . . . . . . . . . 18
2.3. YANG Module . . . . . . . . . . . . . . . . . . . . . . . 27
3. Security Considerations . . . . . . . . . . . . . . . . . . . 47
3.1. No Support for CRMF . . . . . . . . . . . . . . . . . . . 47
3.2. No Support for Key Generation . . . . . . . . . . . . . . 48
3.3. Unconstrained Public Key Usage . . . . . . . . . . . . . 48
3.4. Unconstrained Private Key Usage . . . . . . . . . . . . . 48
3.5. Strength of Keys Conveyed . . . . . . . . . . . . . . . . 48
3.6. Encrypting Passwords . . . . . . . . . . . . . . . . . . 49
3.7. Deletion of Cleartext Key Values . . . . . . . . . . . . 49
3.8. The "ietf-crypto-types" YANG Module . . . . . . . . . . . 49
4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 51
4.1. The "IETF XML" Registry . . . . . . . . . . . . . . . . . 51
4.2. The "YANG Module Names" Registry . . . . . . . . . . . . 51
5. References . . . . . . . . . . . . . . . . . . . . . . . . . 51
5.1. Normative References . . . . . . . . . . . . . . . . . . 51
5.2. Informative References . . . . . . . . . . . . . . . . . 53
Appendix A. Change Log . . . . . . . . . . . . . . . . . . . . . 55
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A.1. I-D to 00 . . . . . . . . . . . . . . . . . . . . . . . . 55
A.2. 00 to 01 . . . . . . . . . . . . . . . . . . . . . . . . 56
A.3. 01 to 02 . . . . . . . . . . . . . . . . . . . . . . . . 56
A.4. 02 to 03 . . . . . . . . . . . . . . . . . . . . . . . . 56
A.5. 03 to 04 . . . . . . . . . . . . . . . . . . . . . . . . 57
A.6. 04 to 05 . . . . . . . . . . . . . . . . . . . . . . . . 57
A.7. 05 to 06 . . . . . . . . . . . . . . . . . . . . . . . . 57
A.8. 06 to 07 . . . . . . . . . . . . . . . . . . . . . . . . 58
A.9. 07 to 08 . . . . . . . . . . . . . . . . . . . . . . . . 58
A.10. 08 to 09 . . . . . . . . . . . . . . . . . . . . . . . . 58
A.11. 09 to 10 . . . . . . . . . . . . . . . . . . . . . . . . 58
A.12. 10 to 11 . . . . . . . . . . . . . . . . . . . . . . . . 59
A.13. 11 to 12 . . . . . . . . . . . . . . . . . . . . . . . . 59
A.14. 12 to 13 . . . . . . . . . . . . . . . . . . . . . . . . 59
A.15. 13 to 14 . . . . . . . . . . . . . . . . . . . . . . . . 59
A.16. 14 to 15 . . . . . . . . . . . . . . . . . . . . . . . . 60
A.17. 15 to 16 . . . . . . . . . . . . . . . . . . . . . . . . 60
A.18. 16 to 17 . . . . . . . . . . . . . . . . . . . . . . . . 61
A.19. 17 to 18 . . . . . . . . . . . . . . . . . . . . . . . . 61
A.20. 18 to 19 . . . . . . . . . . . . . . . . . . . . . . . . 61
A.21. 19 to 20 . . . . . . . . . . . . . . . . . . . . . . . . 61
A.22. 20 to 21 . . . . . . . . . . . . . . . . . . . . . . . . 61
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 62
Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 62
1. Introduction
This document presents a YANG 1.1 [RFC7950] module defining
identities, typedefs, and groupings useful to cryptographic
applications.
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,
enable the configuration of the clients and servers of both the
NETCONF [RFC6241] and RESTCONF [RFC8040] protocols.
The modules have been defined in a modular fashion to enable their
use by other efforts, some of which are known to be in progress at
the time of this writing, with many more expected to be defined in
time.
The normative dependency relationship between the various RFCs in the
collection is presented in the below diagram. The labels in the
diagram represent the primary purpose provided by each RFC.
Hyperlinks to each RFC are provided below the diagram.
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crypto-types
^ ^
/ \
/ \
truststore keystore
^ ^ ^ ^
| +---------+ | |
| | | |
| +------------+ |
tcp-client-server | / | |
^ ^ ssh-client-server | |
| | ^ tls-client-server
| | | ^ ^ http-client-server
| | | | | ^
| | | +-----+ +---------+ |
| | | | | |
| +-----------|--------|--------------+ | |
| | | | | |
+-----------+ | | | | |
| | | | | |
| | | | | |
netconf-client-server restconf-client-server
+=======================+===========================================+
|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 to RFC Mapping
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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. Adherence to the NMDA
This document is compliant with the Network Management Datastore
Architecture (NMDA) [RFC8342]. It does not define any protocol
accessible nodes that are "config false".
1.4. Conventions
Various examples used in this document use a placeholder value for
binary data that has been base64 encoded (e.g., "BASE64VALUE=").
This placeholder value is used as real base64 encoded structures are
often many lines long and hence distracting to the example being
presented.
2. The "ietf-crypto-types" Module
This section defines a YANG 1.1 [RFC7950] module called "ietf-crypto-
types". A high-level overview of the module is provided in
Section 2.1. Examples illustrating the module's use are provided in
Examples (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-crypto-types" module
in terms of its features, identities, typedefs, and groupings.
2.1.1. Features
The following diagram lists all the "feature" statements defined in
the "ietf-crypto-types" module:
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Features:
+-- one-symmetric-key-format
+-- one-asymmetric-key-format
+-- certificate-signing-request-generation
+-- certificate-expiration-notification
+-- symmetrically-encrypted-value-format
+-- asymmetrically-encrypted-value-format
+-- cms-encrypted-data-format
+-- cms-enveloped-data-format
| The diagram above uses syntax that is similar to but not
| defined in [RFC8340].
2.1.2. Identities
The following diagram illustrates the relationship amongst the
"identity" statements defined in the "ietf-crypto-types" module:
Identities:
+-- public-key-format
| +-- subject-public-key-info-format
| +-- ssh-public-key-format
+-- private-key-format
| +-- rsa-private-key-format
| +-- ec-private-key-format
| +-- one-asymmetric-key-format
| {one-asymmetric-key-format}?
+-- symmetric-key-format
| +-- octet-string-key-format
| +-- one-symmetric-key-format
| {one-symmetric-key-format}?
+-- encrypted-value-format
+-- symmetrically-encrypted-value-format
| | {symmetrically-encrypted-value-format}?
| +-- cms-encrypted-data-format
| {cms-encrypted-data-format}?
+-- asymmetrically-encrypted-value-format
| {asymmetrically-encrypted-value-format}?
+-- cms-enveloped-data-format
{cms-enveloped-data-format}?
| The diagram above uses syntax that is similar to but not
| defined in [RFC8340].
Comments:
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* The diagram shows that there are four base identities. The first
three identities are used to indicate the format that key data,
while the fourth identity is used to indicate the format for
encrypted values. The base identities are "abstract", in the
object oriented programming sense, in that they only define a
"class" of formats, rather than a specific format.
* The various "leaf" identities define specific encoding formats.
The derived identities defined in this document are sufficient for
the effort described in Section 1.1 but, by nature of them being
identities, additional derived identities MAY be defined by future
efforts.
* Identities used to specify uncommon formats are enabled by
"feature" statements, allowing applications to support them when
needed.
2.1.3. Typedefs
The following diagram illustrates the relationship amongst the
"typedef" statements defined in the "ietf-crypto-types" module:
Typedefs:
binary
+-- csr-info
+-- csr
+-- x509
| +-- trust-anchor-cert-x509
| +-- end-entity-cert-x509
+-- crl
+-- ocsp-request
+-- ocsp-response
+-- cms
+-- data-content-cms
+-- signed-data-cms
| +-- trust-anchor-cert-cms
| +-- end-entity-cert-cms
+-- enveloped-data-cms
+-- digested-data-cms
+-- encrypted-data-cms
+-- authenticated-data-cms
| The diagram above uses syntax that is similar to but not
| defined in [RFC8340].
Comments:
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* All the typedefs defined in the "ietf-crypto-types" module extend
the "binary" type defined in [RFC7950].
* Additionally, all the typedefs define a type for encoding an ASN.1
[ITU.X680.2015] structure using DER [ITU.X690.2015].
* The "trust-anchor-*" and "end-entity-*" typedefs are syntactically
identical to their base typedefs and only distinguish themselves
by the expected nature of their content. These typedefs are
defined to facilitate common modeling needs.
2.1.4. Groupings
The "ietf-crypto-types" module defines the following "grouping"
statements:
* encrypted-value-grouping
* password-grouping
* symmetric-key-grouping
* public-key-grouping
* asymmetric-key-pair-grouping
* trust-anchor-cert-grouping
* end-entity-cert-grouping
* generate-csr-grouping
* asymmetric-key-pair-with-cert-grouping
* asymmetric-key-pair-with-certs-grouping
Each of these groupings are presented in the following subsections.
2.1.4.1. The "encrypted-value-grouping" Grouping
The following tree diagram [RFC8340] illustrates the "encrypted-
value-grouping" grouping:
grouping encrypted-value-grouping
+-- encrypted-by
+-- encrypted-value-format identityref
+-- encrypted-value binary
Comments:
* The "encrypted-by" node is an empty container (difficult to see in
the diagram) that a consuming module MUST augment key references
into. The "ietf-crypto-types" module is unable to populate this
container as the module only defines groupings. Section 2.2.1
presents an example illustrating a consuming module populating the
"encrypted-by" container.
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* The "encrypted-value" node is the value, encrypted by the key
referenced by the "encrypted-by" node, and encoded in the format
appropriate for the kind of key it was encrypted by.
- If the value is encrypted by a symmetric key, then the
encrypted value is encoded using the format associated with the
"symmetrically-encrypted-value-format" identity.
- If the value is encrypted by an asymmetric key, then the
encrypted value is encoded using the format associated with the
"asymmetrically-encrypted-value-format" identity.
See Section 2.1.2 for information about the "format" identities.
2.1.4.2. The "password-grouping" Grouping
This section presents two tree diagrams [RFC8340] illustrating the
"password-grouping" grouping. The first tree diagram does not expand
the internally used grouping statement(s):
grouping password-grouping
+-- (password-type)
+--:(cleartext-password)
| +-- cleartext-password? string
+--:(encrypted-password) {password-encryption}?
+-- encrypted-password
+---u encrypted-value-grouping
The following tree diagram expands the internally used grouping
statement(s), enabling the grouping's full structure to be seen:
grouping password-grouping
+-- (password-type)
+--:(cleartext-password)
| +-- cleartext-password? string
+--:(encrypted-password) {password-encryption}?
+-- encrypted-password
+-- encrypted-by
+-- encrypted-value-format identityref
+-- encrypted-value binary
Comments:
* For the referenced grouping statement(s):
- The "encrypted-value-grouping" grouping is discussed in
Section 2.1.4.1.
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* The "choice" statement enables the password data to be cleartext
or encrypted, as follows:
- The "cleartext-password" node can encode any cleartext value.
- The "encrypted-password" node's structure is discussed in
Section 2.1.4.1.
2.1.4.3. The "symmetric-key-grouping" Grouping
This section presents two tree diagrams [RFC8340] illustrating the
"symmetric-key-grouping" grouping. The first tree diagram does not
expand the internally used grouping statement(s):
grouping symmetric-key-grouping
+-- key-format? identityref
+-- (key-type)
+--:(cleartext-key)
| +-- cleartext-key? binary
+--:(hidden-key)
| +-- hidden-key? empty
+--:(encrypted-key) {symmetric-key-encryption}?
+-- encrypted-key
+---u encrypted-value-grouping
The following tree diagram expands the internally used grouping
statement(s), enabling the grouping's full structure to be seen:
grouping symmetric-key-grouping
+-- key-format? identityref
+-- (key-type)
+--:(cleartext-key)
| +-- cleartext-key? binary
+--:(hidden-key)
| +-- hidden-key? empty
+--:(encrypted-key) {symmetric-key-encryption}?
+-- encrypted-key
+-- encrypted-by
+-- encrypted-value-format identityref
+-- encrypted-value binary
Comments:
* For the referenced grouping statement(s):
- The "encrypted-value-grouping" grouping is discussed in
Section 2.1.4.1.
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* The "key-format" node is an identity-reference to the "symmetric-
key-format" abstract base identity discussed in Section 2.1.2,
enabling the symmetric key to be encoded using the format defined
by any of the derived identities.
* The "choice" statement enables the private key data to be
cleartext, encrypted, or hidden, as follows:
- The "cleartext-key" node can encode any cleartext key value.
- The "hidden-key" node is of type "empty" as the real value
cannot be presented via the management interface.
- The "encrypted-key" node's structure is discussed in
Section 2.1.4.1.
2.1.4.4. The "public-key-grouping" Grouping
The following tree diagram [RFC8340] illustrates the "public-key-
grouping" grouping:
grouping public-key-grouping
+-- public-key-format identityref
+-- public-key binary
Comments:
* The "public-key-format" node is an identity-reference to the
"public-key-format" abstract base identity discussed in
Section 2.1.2, enabling the public key to be encoded using the
format defined by any of the derived identities.
* The "public-key" node is the public key data in the selected
format. No "choice" statement is used to hide or encrypt the
public key data because it is unnecessary to do so for public
keys.
2.1.4.5. The "asymmetric-key-pair-grouping" Grouping
This section presents two tree diagrams [RFC8340] illustrating the
"asymmetric-key-pair-grouping" grouping. The first tree diagram does
not expand the internally used grouping statement(s):
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grouping asymmetric-key-pair-grouping
+---u public-key-grouping
+-- private-key-format? identityref
+-- (private-key-type)
+--:(cleartext-private-key)
| +-- cleartext-private-key? binary
+--:(hidden-private-key)
| +-- hidden-private-key? empty
+--:(encrypted-private-key) {private-key-encryption}?
+-- encrypted-private-key
+---u encrypted-value-grouping
The following tree diagram expands the internally used grouping
statement(s), enabling the grouping's full structure to be seen:
grouping asymmetric-key-pair-grouping
+-- public-key-format identityref
+-- public-key binary
+-- private-key-format? identityref
+-- (private-key-type)
+--:(cleartext-private-key)
| +-- cleartext-private-key? binary
+--:(hidden-private-key)
| +-- hidden-private-key? empty
+--:(encrypted-private-key) {private-key-encryption}?
+-- encrypted-private-key
+-- encrypted-by
+-- encrypted-value-format identityref
+-- encrypted-value binary
Comments:
* For the referenced grouping statement(s):
- The "public-key-grouping" grouping is discussed in
Section 2.1.4.4.
- The "encrypted-value-grouping" grouping is discussed in
Section 2.1.4.1.
* The "private-key-format" node is an identity-reference to the
"private-key-format" abstract base identity discussed in
Section 2.1.2, enabling the private key to be encoded using the
format defined by any of the derived identities.
* The "choice" statement enables the private key data to be
cleartext, encrypted, or hidden, as follows:
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- The "cleartext-private-key" node can encode any cleartext key
value.
- The "hidden-private-key" node is of type "empty" as the real
value cannot be presented via the management interface.
- The "encrypted-private-key" node's structure is discussed in
Section 2.1.4.1.
2.1.4.6. The "certificate-expiration-grouping" Grouping
The following tree diagram [RFC8340] illustrates the "certificate-
expiration-grouping" grouping:
grouping certificate-expiration-grouping
+---n certificate-expiration
{certificate-expiration-notification}?
+-- expiration-date yang:date-and-time
Comments:
* This grouping's only purpose is to define the "certificate-
expiration" notification statement, used by the groupings defined
in Section 2.1.4.7 and Section 2.1.4.8.
* The "certificate-expiration" notification enables servers to
notify clients when certificates are nearing expiration.
* The "expiration-date" node indicates when the designated
certificate will (or did) expire.
* Identification of the certificate that is expiring is built into
the notification itself. For an example, please see
Section 2.2.3.
2.1.4.7. The "trust-anchor-cert-grouping" Grouping
This section presents two tree diagrams [RFC8340] illustrating the
"trust-anchor-cert-grouping" grouping. The first tree diagram does
not expand the internally used grouping statement(s):
grouping trust-anchor-cert-grouping
+-- cert-data? trust-anchor-cert-cms
+---u certificate-expiration-grouping
The following tree diagram expands the internally used grouping
statement(s), enabling the grouping's full structure to be seen:
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grouping trust-anchor-cert-grouping
+-- cert-data? trust-anchor-cert-cms
+---n certificate-expiration
{certificate-expiration-notification}?
+-- expiration-date yang:date-and-time
Comments:
* For the referenced grouping statement(s):
- The "certificate-expiration-grouping" grouping is discussed in
Section 2.1.4.6.
* The "cert-data" node contains a chain of one or more certificates
encoded using a "signed-data-cms" typedef discussed in
Section 2.1.3.
2.1.4.8. The "end-entity-cert-grouping" Grouping
This section presents two tree diagrams [RFC8340] illustrating the
"end-entity-cert-grouping" grouping. The first tree diagram does not
expand the internally used grouping statement(s):
grouping end-entity-cert-grouping
+-- cert-data? end-entity-cert-cms
+---u certificate-expiration-grouping
The following tree diagram expands the internally used grouping
statement(s), enabling the grouping's full structure to be seen:
grouping end-entity-cert-grouping
+-- cert-data? end-entity-cert-cms
+---n certificate-expiration
{certificate-expiration-notification}?
+-- expiration-date yang:date-and-time
Comments:
* For the referenced grouping statement(s):
- The "certificate-expiration-grouping" grouping is discussed in
Section 2.1.4.6.
* The "cert-data" node contains a chain of one or more certificates
encoded using a "signed-data-cms" typedef discussed in
Section 2.1.3.
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2.1.4.9. The "generate-csr-grouping" Grouping
The following tree diagram [RFC8340] illustrates the "generate-csr-
grouping" grouping:
grouping generate-csr-grouping
+---x generate-certificate-signing-request
{certificate-signing-request-generation}?
+---w input
| +---w csr-info ct:csr-info
+--ro output
+--ro certificate-signing-request ct:csr
Comments:
* This grouping's only purpose is to define the "generate-
certificate-signing-request" action statement, used by the
groupings defined in Section 2.1.4.10 and Section 2.1.4.11.
* This action takes as input a "csr-info" type and returns a "csr"
type, both of which are discussed in Section 2.1.3.
* For an example, please see Section 2.2.2.
2.1.4.10. The "asymmetric-key-pair-with-cert-grouping" Grouping
This section presents two tree diagrams [RFC8340] illustrating the
"asymmetric-key-pair-with-cert-grouping" grouping. The first tree
diagram does not expand the internally used grouping statement(s):
grouping asymmetric-key-pair-with-cert-grouping
+---u asymmetric-key-pair-grouping
+---u end-entity-cert-grouping
+---u generate-csr-grouping
The following tree diagram expands the internally used grouping
statement(s), enabling the grouping's full structure to be seen:
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grouping asymmetric-key-pair-with-cert-grouping
+-- public-key-format identityref
+-- public-key binary
+-- private-key-format? identityref
+-- (private-key-type)
| +--:(cleartext-private-key)
| | +-- cleartext-private-key? binary
| +--:(hidden-private-key)
| | +-- hidden-private-key? empty
| +--:(encrypted-private-key) {private-key-encryption}?
| +-- encrypted-private-key
| +-- encrypted-by
| +-- encrypted-value-format identityref
| +-- encrypted-value binary
+-- cert-data? end-entity-cert-cms
+---n certificate-expiration
| {certificate-expiration-notification}?
| +-- expiration-date yang:date-and-time
+---x generate-certificate-signing-request
{certificate-signing-request-generation}?
+---w input
| +---w csr-info ct:csr-info
+--ro output
+--ro certificate-signing-request ct:csr
Comments:
* This grouping defines an asymmetric key with at most one
associated certificate, a commonly needed combination in protocol
models.
* For the referenced grouping statement(s):
- The "asymmetric-key-pair-grouping" grouping is discussed in
Section 2.1.4.5.
- The "end-entity-cert-grouping" grouping is discussed in
Section 2.1.4.8.
- The "generate-csr-grouping" grouping is discussed in
Section 2.1.4.9.
2.1.4.11. The "asymmetric-key-pair-with-certs-grouping" Grouping
This section presents two tree diagrams [RFC8340] illustrating the
"asymmetric-key-pair-with-certs-grouping" grouping. The first tree
diagram does not expand the internally used grouping statement(s):
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grouping asymmetric-key-pair-with-certs-grouping
+---u asymmetric-key-pair-grouping
+-- certificates
| +-- certificate* [name]
| +-- name? string
| +---u end-entity-cert-grouping
+---u generate-csr-grouping
The following tree diagram expands the internally used grouping
statement(s), enabling the grouping's full structure to be seen:
grouping asymmetric-key-pair-with-certs-grouping
+-- public-key-format identityref
+-- public-key binary
+-- private-key-format? identityref
+-- (private-key-type)
| +--:(cleartext-private-key)
| | +-- cleartext-private-key? binary
| +--:(hidden-private-key)
| | +-- hidden-private-key? empty
| +--:(encrypted-private-key) {private-key-encryption}?
| +-- encrypted-private-key
| +-- encrypted-by
| +-- encrypted-value-format identityref
| +-- encrypted-value binary
+-- certificates
| +-- certificate* [name]
| +-- name? string
| +-- cert-data end-entity-cert-cms
| +---n certificate-expiration
| {certificate-expiration-notification}?
| +-- expiration-date yang:date-and-time
+---x generate-certificate-signing-request
{certificate-signing-request-generation}?
+---w input
| +---w csr-info ct:csr-info
+--ro output
+--ro certificate-signing-request ct:csr
Comments:
* This grouping defines an asymmetric key with one or more
associated certificates, a commonly needed combination in
configuration models.
* For the referenced grouping statement(s):
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- The "asymmetric-key-pair-grouping" grouping is discussed in
Section 2.1.4.5.
- The "end-entity-cert-grouping" grouping is discussed in
Section 2.1.4.8.
- The "generate-csr-grouping" grouping is discussed in
Section 2.1.4.9.
2.1.5. Protocol-accessible Nodes
The "ietf-crypto-types" module does not contain any protocol-
accessible nodes, but the module needs to be "implemented", as
described in Section 5.6.5 of [RFC7950], in order for the identities
in Section 2.1.2 to be defined.
2.2. Example Usage
2.2.1. The "symmetric-key-grouping" and "asymmetric-key-pair-with-
certs-grouping" Grouping
The following non-normative module is constructed in order to
illustrate the use of the "symmetric-key-grouping" (Section 2.1.4.3),
the "asymmetric-key-pair-with-certs-grouping" (Section 2.1.4.11), and
the "password-grouping" (Section 2.1.4.2) grouping statements.
Notably, this example illustrates a hidden asymmetric key (ex-hidden-
asymmetric-key) has been used to encrypt a symmetric key (ex-
encrypted-one-symmetric-based-symmetric-key) that has been used to
encrypt another asymmetric key (ex-encrypted-rsa-based-asymmetric-
key). Additionally, the symmetric key is also used to encrypt a
password (ex-encrypted-password).
module ex-crypto-types-usage {
yang-version 1.1;
namespace "http://example.com/ns/example-crypto-types-usage";
prefix ectu;
import ietf-crypto-types {
prefix ct;
reference
"RFC AAAA: YANG Data Types and Groupings for Cryptography";
}
organization
"Example Corporation";
contact
"YANG Designer <mailto:yang.designer@example.com>";
description
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"This module illustrates the 'symmetric-key-grouping'
and 'asymmetric-key-grouping' groupings defined in
the 'ietf-crypto-types' module defined in RFC AAAA.";
revision 2021-09-14 {
description
"Initial version";
reference
"RFC AAAA: Common YANG Data Types for Cryptography";
}
container symmetric-keys {
description
"A container of symmetric keys.";
list symmetric-key {
key "name";
description
"A symmetric key";
leaf name {
type string;
description
"An arbitrary name for this key.";
}
uses ct:symmetric-key-grouping {
augment "key-type/encrypted-key/encrypted-key/"
+ "encrypted-by" {
description
"Augments in a choice statement enabling the
encrypting key to be any other symmetric or
asymmetric key.";
uses encrypted-by-choice-grouping;
}
}
}
}
container asymmetric-keys {
description
"A container of asymmetric keys.";
list asymmetric-key {
key "name";
leaf name {
type string;
description
"An arbitrary name for this key.";
}
uses ct:asymmetric-key-pair-with-certs-grouping {
augment "private-key-type/encrypted-private-key/"
+ "encrypted-private-key/encrypted-by" {
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description
"Augments in a choice statement enabling the
encrypting key to be any other symmetric or
asymmetric key.";
uses encrypted-by-choice-grouping;
}
}
description
"An asymmetric key pair with associated certificates.";
}
}
container passwords {
description
"A container of passwords.";
list password {
key "name";
leaf name {
type string;
description
"An arbitrary name for this password.";
}
uses ct:password-grouping {
augment "password-type/encrypted-password/"
+ "encrypted-password/encrypted-by" {
description
"Augments in a choice statement enabling the
encrypting key to be any symmetric or
asymmetric key.";
uses encrypted-by-choice-grouping;
}
}
description
"A password.";
}
}
grouping encrypted-by-choice-grouping {
description
"A grouping that defines a choice enabling references
to other keys.";
choice encrypted-by-choice {
mandatory true;
description
"A choice amongst other symmetric or asymmetric keys.";
case symmetric-key-ref {
leaf symmetric-key-ref {
type leafref {
path "/ectu:symmetric-keys/ectu:symmetric-key/"
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+ "ectu:name";
}
description
"Identifies the symmetric key that encrypts this key.";
}
}
case asymmetric-key-ref {
leaf asymmetric-key-ref {
type leafref {
path "/ectu:asymmetric-keys/ectu:asymmetric-key/"
+ "ectu:name";
}
description
"Identifies the asymmetric key that encrypts this key.";
}
}
}
}
}
The tree diagram [RFC8340] for this example module follows:
module: ex-crypto-types-usage
+--rw symmetric-keys
| +--rw symmetric-key* [name]
| +--rw name string
| +--rw key-format? identityref
| +--rw (key-type)
| +--:(cleartext-key)
| | +--rw cleartext-key? binary
| +--:(hidden-key)
| | +--rw hidden-key? empty
| +--:(encrypted-key) {symmetric-key-encryption}?
| +--rw encrypted-key
| +--rw encrypted-by
| | +--rw (encrypted-by-choice)
| | +--:(symmetric-key-ref)
| | | +--rw symmetric-key-ref? leafref
| | +--:(asymmetric-key-ref)
| | +--rw asymmetric-key-ref? leafref
| +--rw encrypted-value-format identityref
| +--rw encrypted-value binary
+--rw asymmetric-keys
| +--rw asymmetric-key* [name]
| +--rw name string
| +--rw public-key-format identityref
| +--rw public-key binary
| +--rw private-key-format? identityref
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| +--rw (private-key-type)
| | +--:(cleartext-private-key)
| | | +--rw cleartext-private-key? binary
| | +--:(hidden-private-key)
| | | +--rw hidden-private-key? empty
| | +--:(encrypted-private-key) {private-key-encryption}?
| | +--rw encrypted-private-key
| | +--rw encrypted-by
| | | +--rw (encrypted-by-choice)
| | | +--:(symmetric-key-ref)
| | | | +--rw symmetric-key-ref? leafref
| | | +--:(asymmetric-key-ref)
| | | +--rw asymmetric-key-ref? leafref
| | +--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-certificate-signing-request
| {certificate-signing-request-generation}?
| +---w input
| | +---w csr-info ct:csr-info
| +--ro output
| +--ro certificate-signing-request ct:csr
+--rw passwords
+--rw password* [name]
+--rw name string
+--rw (password-type)
+--:(cleartext-password)
| +--rw cleartext-password? string
+--:(encrypted-password) {password-encryption}?
+--rw encrypted-password
+--rw encrypted-by
| +--rw (encrypted-by-choice)
| +--:(symmetric-key-ref)
| | +--rw symmetric-key-ref? leafref
| +--:(asymmetric-key-ref)
| +--rw asymmetric-key-ref? leafref
+--rw encrypted-value-format identityref
+--rw encrypted-value binary
Finally, the following example illustrates various symmetric and
asymmetric keys as they might appear in configuration:
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=============== NOTE: '\' line wrapping per RFC 8792 ================
<symmetric-keys
xmlns="http://example.com/ns/example-crypto-types-usage"
xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-crypto-types">
<symmetric-key>
<name>ex-hidden-symmetric-key</name>
<hidden-key/>
</symmetric-key>
<symmetric-key>
<name>ex-octet-string-based-symmetric-key</name>
<key-format>ct:octet-string-key-format</key-format>
<cleartext-key>BASE64VALUE=</cleartext-key>
</symmetric-key>
<symmetric-key>
<name>ex-one-symmetric-based-symmetric-key</name>
<key-format>ct:one-symmetric-key-format</key-format>
<cleartext-key>BASE64VALUE=</cleartext-key>
</symmetric-key>
<symmetric-key>
<name>ex-encrypted-one-symmetric-based-symmetric-key</name>
<key-format>ct:one-symmetric-key-format</key-format>
<encrypted-key>
<encrypted-by>
<asymmetric-key-ref>ex-hidden-asymmetric-key</asymmetric-key\
-ref>
</encrypted-by>
<encrypted-value-format>
ct:cms-enveloped-data-format
</encrypted-value-format>
<encrypted-value>BASE64VALUE=</encrypted-value>
</encrypted-key>
</symmetric-key>
</symmetric-keys>
<asymmetric-keys
xmlns="http://example.com/ns/example-crypto-types-usage"
xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-crypto-types">
<asymmetric-key>
<name>ex-hidden-asymmetric-key</name>
<public-key-format>
ct:subject-public-key-info-format
</public-key-format>
<public-key>BASE64VALUE=</public-key>
<hidden-private-key/>
<certificates>
<certificate>
<name>ex-hidden-asymmetric-key-cert</name>
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<cert-data>BASE64VALUE=</cert-data>
</certificate>
</certificates>
</asymmetric-key>
<asymmetric-key>
<name>ex-rsa-based-asymmetric-key</name>
<public-key-format>
ct:subject-public-key-info-format
</public-key-format>
<public-key>BASE64VALUE=</public-key>
<private-key-format>
ct:rsa-private-key-format
</private-key-format>
<cleartext-private-key>BASE64VALUE=</cleartext-private-key>
<certificates>
<certificate>
<name>ex-cert</name>
<cert-data>BASE64VALUE=</cert-data>
</certificate>
</certificates>
</asymmetric-key>
<asymmetric-key>
<name>ex-one-asymmetric-based-asymmetric-key</name>
<public-key-format>
ct:subject-public-key-info-format
</public-key-format>
<public-key>BASE64VALUE=</public-key>
<private-key-format>
ct:one-asymmetric-key-format
</private-key-format>
<cleartext-private-key>BASE64VALUE=</cleartext-private-key>
</asymmetric-key>
<asymmetric-key>
<name>ex-encrypted-rsa-based-asymmetric-key</name>
<public-key-format>
ct:subject-public-key-info-format
</public-key-format>
<public-key>BASE64VALUE=</public-key>
<private-key-format>
ct:rsa-private-key-format
</private-key-format>
<encrypted-private-key>
<encrypted-by>
<symmetric-key-ref>ex-encrypted-one-symmetric-based-symmetri\
c-key</symmetric-key-ref>
</encrypted-by>
<encrypted-value-format>
ct:cms-encrypted-data-format
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</encrypted-value-format>
<encrypted-value>BASE64VALUE=</encrypted-value>
</encrypted-private-key>
</asymmetric-key>
</asymmetric-keys>
<passwords
xmlns="http://example.com/ns/example-crypto-types-usage"
xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-crypto-types">
<password>
<name>ex-cleartext-password</name>
<cleartext-password>super-secret</cleartext-password>
</password>
<password>
<name>ex-encrypted-password</name>
<encrypted-password>
<encrypted-by>
<symmetric-key-ref>ex-encrypted-one-symmetric-based-symmetri\
c-key</symmetric-key-ref>
</encrypted-by>
<encrypted-value-format>
ct:cms-encrypted-data-format
</encrypted-value-format>
<encrypted-value>BASE64VALUE=</encrypted-value>
</encrypted-password>
</password>
</passwords>
2.2.2. The "generate-certificate-signing-request" Action
The following example illustrates the "generate-certificate-signing-
request" action, discussed in Section 2.1.4.9, with the NETCONF
protocol.
REQUEST
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<rpc message-id="101"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<action xmlns="urn:ietf:params:xml:ns:yang:1">
<asymmetric-keys
xmlns="http://example.com/ns/example-crypto-types-usage">
<asymmetric-key>
<name>ex-key-sect571r1</name>
<generate-certificate-signing-request>
<csr-info>BASE64VALUE=</csr-info>
</generate-certificate-signing-request>
</asymmetric-key>
</asymmetric-keys>
</action>
</rpc>
RESPONSE
<rpc-reply message-id="101"
xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
<certificate-signing-request
xmlns="http://example.com/ns/example-crypto-types-usage">
BASE64VALUE=
</certificate-signing-request>
</rpc-reply>
2.2.3. The "certificate-expiration" Notification
The following example illustrates the "certificate-expiration"
notification, discussed in Section 2.1.4.6, with the NETCONF
protocol.
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=============== NOTE: '\' line wrapping per RFC 8792 ================
<notification
xmlns="urn:ietf:params:xml:ns:netconf:notification:1.0">
<eventTime>2018-05-25T00:01:00Z</eventTime>
<asymmetric-keys xmlns="http://example.com/ns/example-crypto-types\
-usage">
<asymmetric-key>
<name>ex-hidden-asymmetric-key</name>
<certificates>
<certificate>
<name>ex-hidden-asymmetric-key</name>
<certificate-expiration>
<expiration-date>2018-08-05T14:18:53-05:00</expiration-d\
ate>
</certificate-expiration>
</certificate>
</certificates>
</asymmetric-key>
</asymmetric-keys>
</notification>
2.3. YANG Module
This module has normative references to [RFC2119], [RFC2986],
[RFC3447], [RFC4253], [RFC5280], [RFC5652], [RFC5915], [RFC5958],
[RFC6031], [RFC6125], [RFC6991], [RFC7093], [RFC8174], [RFC8341], and
[ITU.X690.2015].
<CODE BEGINS> file "ietf-crypto-types@2021-09-14.yang"
module ietf-crypto-types {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-crypto-types";
prefix ct;
import ietf-yang-types {
prefix yang;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-netconf-acm {
prefix nacm;
reference
"RFC 8341: Network Configuration Access Control Model";
}
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organization
"IETF NETCONF (Network Configuration) Working Group";
contact
"WG Web: <http://datatracker.ietf.org/wg/netconf/>
WG List: <mailto:netconf@ietf.org>
Author: Kent Watsen <mailto:kent+ietf@watsen.net>";
description
"This module defines common YANG types for cryptographic
applications.
Copyright (c) 2021 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 Simplified
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 AAAA
(https://www.rfc-editor.org/info/rfcAAAA); 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 2021-09-14 {
description
"Initial version";
reference
"RFC AAAA: YANG Data Types and Groupings for Cryptography";
}
/****************/
/* Features */
/****************/
feature one-symmetric-key-format {
description
"Indicates that the server supports the
'one-symmetric-key-format' identity.";
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}
feature one-asymmetric-key-format {
description
"Indicates that the server supports the
'one-asymmetric-key-format' identity.";
}
feature symmetrically-encrypted-value-format {
description
"Indicates that the server supports the
'symmetrically-encrypted-value-format' identity.";
}
feature asymmetrically-encrypted-value-format {
description
"Indicates that the server supports the
'asymmetrically-encrypted-value-format' identity.";
}
feature cms-enveloped-data-format {
description
"Indicates that the server supports the
'cms-enveloped-data-format' identity.";
}
feature cms-encrypted-data-format {
description
"Indicates that the server supports the
'cms-encrypted-data-format' identity.";
}
feature certificate-signing-request-generation {
description
"Indicates that the server implements the
'generate-certificate-signing-request' action.";
}
feature certificate-expiration-notification {
description
"Indicates that the server implements the
'certificate-expiration' notification.";
}
feature password-encryption {
description
"Indicates that the server supports password
encryption.";
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}
feature symmetric-key-encryption {
description
"Indicates that the server supports encryption
of symmetric keys.";
}
feature private-key-encryption {
description
"Indicates that the server supports encryption
of private keys.";
}
/*************************************************/
/* Base Identities for Key Format Structures */
/*************************************************/
identity symmetric-key-format {
description
"Base key-format identity for symmetric keys.";
}
identity public-key-format {
description
"Base key-format identity for public keys.";
}
identity private-key-format {
description
"Base key-format identity for private keys.";
}
/****************************************************/
/* Identities for Private Key Format Structures */
/****************************************************/
identity rsa-private-key-format {
base private-key-format;
description
"Indicates that the private key value is encoded
as an RSAPrivateKey (from RFC 3447).";
reference
"RFC 3447: PKCS #1: RSA Cryptography
Specifications Version 2.2";
}
identity ec-private-key-format {
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base private-key-format;
description
"Indicates that the private key value is encoded
as an ECPrivateKey (from RFC 5915)";
reference
"RFC 5915: Elliptic Curve Private Key Structure";
}
identity one-asymmetric-key-format {
if-feature "one-asymmetric-key-format";
base private-key-format;
description
"Indicates that the private key value is a CMS
OneAsymmetricKey structure, as defined in RFC 5958,
encoded using ASN.1 distinguished encoding rules
(DER), as specified in ITU-T X.690.";
reference
"RFC 5958: Asymmetric Key Packages
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
/***************************************************/
/* Identities for Public Key Format Structures */
/***************************************************/
identity ssh-public-key-format {
base public-key-format;
description
"Indicates that the public key value is an SSH public key,
as specified by RFC 4253, Section 6.6, i.e.:
string certificate or public key format
identifier
byte[n] key/certificate data.";
reference
"RFC 4253: The Secure Shell (SSH) Transport Layer Protocol";
}
identity subject-public-key-info-format {
base public-key-format;
description
"Indicates that the public key value is a SubjectPublicKeyInfo
structure, as described in RFC 5280 encoded using ASN.1
distinguished encoding rules (DER), as specified in
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ITU-T X.690.";
reference
"RFC 5280:
Internet X.509 Public Key Infrastructure Certificate
and Certificate Revocation List (CRL) Profile
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
/******************************************************/
/* Identities for Symmetric Key Format Structures */
/******************************************************/
identity octet-string-key-format {
base symmetric-key-format;
description
"Indicates that the key is encoded as a raw octet string.
The length of the octet string MUST be appropriate for
the associated algorithm's block size.
How the associated algorithm is known is outside the
scope of this module. This statement also applies when
the octet string has been encrypted.";
}
identity one-symmetric-key-format {
if-feature "one-symmetric-key-format";
base symmetric-key-format;
description
"Indicates that the private key value is a CMS
OneSymmetricKey structure, as defined in RFC 6031,
encoded using ASN.1 distinguished encoding rules
(DER), as specified in ITU-T X.690.";
reference
"RFC 6031: Cryptographic Message Syntax (CMS)
Symmetric Key Package Content Type
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
/*************************************************/
/* Identities for Encrypted Value Structures */
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/*************************************************/
identity encrypted-value-format {
description
"Base format identity for encrypted values.";
}
identity symmetrically-encrypted-value-format {
if-feature "symmetrically-encrypted-value-format";
base encrypted-value-format;
description
"Base format identity for symmetrically encrypted
values.";
}
identity asymmetrically-encrypted-value-format {
if-feature "asymmetrically-encrypted-value-format";
base encrypted-value-format;
description
"Base format identity for asymmetrically encrypted
values.";
}
identity cms-encrypted-data-format {
if-feature "cms-encrypted-data-format";
base symmetrically-encrypted-value-format;
description
"Indicates that the encrypted value conforms to
the 'encrypted-data-cms' type with the constraint
that the 'unprotectedAttrs' value is not set.";
reference
"RFC 5652: Cryptographic Message Syntax (CMS)
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
identity cms-enveloped-data-format {
if-feature "cms-enveloped-data-format";
base asymmetrically-encrypted-value-format;
description
"Indicates that the encrypted value conforms to the
'enveloped-data-cms' type with the following constraints:
The EnvelopedData structure MUST have exactly one
'RecipientInfo'.
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If the asymmetric key supports public key cryptography
(e.g., RSA), then the 'RecipientInfo' must be a
'KeyTransRecipientInfo' with the 'RecipientIdentifier'
using a 'subjectKeyIdentifier' with the value set using
'method 1' in RFC 7093 over the recipient's public key.
Otherwise, if the asymmetric key supports key agreement
(e.g., ECC), then the 'RecipientInfo' must be a
'KeyAgreeRecipientInfo'. The 'OriginatorIdentifierOrKey'
value must use the 'OriginatorPublicKey' alternative.
The 'UserKeyingMaterial' value must not be present.
There must be exactly one 'RecipientEncryptedKeys' value
having the 'KeyAgreeRecipientIdentifier' set to 'rKeyId'
with the value set using 'method 1' in RFC 7093 over the
recipient's public key.";
reference
"RFC 5652: Cryptographic Message Syntax (CMS)
RFC 7093:
Additional Methods for Generating Key
Identifiers Values
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
/***************************************************/
/* Typedefs for ASN.1 structures from RFC 2986 */
/***************************************************/
typedef csr-info {
type binary;
description
"A CertificationRequestInfo structure, as defined in
RFC 2986, encoded using ASN.1 distinguished encoding
rules (DER), as specified in ITU-T X.690.";
reference
"RFC 2986: PKCS #10: Certification Request Syntax
Specification Version 1.7
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
typedef csr {
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type binary;
description
"A CertificationRequest structure, as specified in
RFC 2986, encoded using ASN.1 distinguished encoding
rules (DER), as specified in ITU-T X.690.";
reference
"RFC 2986:
PKCS #10: Certification Request Syntax Specification
Version 1.7
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
/***************************************************/
/* Typedefs for ASN.1 structures from RFC 5280 */
/***************************************************/
typedef x509 {
type binary;
description
"A Certificate structure, as specified in RFC 5280,
encoded using ASN.1 distinguished encoding rules (DER),
as specified in ITU-T X.690.";
reference
"RFC 5280:
Internet X.509 Public Key Infrastructure Certificate
and Certificate Revocation List (CRL) Profile
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
typedef crl {
type binary;
description
"A CertificateList structure, as specified in RFC 5280,
encoded using ASN.1 distinguished encoding rules (DER),
as specified in ITU-T X.690.";
reference
"RFC 5280:
Internet X.509 Public Key Infrastructure Certificate
and Certificate Revocation List (CRL) Profile
ITU-T X.690:
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Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
/***************************************************/
/* Typedefs for ASN.1 structures from RFC 6960 */
/***************************************************/
typedef oscp-request {
type binary;
description
"A OCSPRequest structure, as specified in RFC 6960,
encoded using ASN.1 distinguished encoding rules
(DER), as specified in ITU-T X.690.";
reference
"RFC 6960:
X.509 Internet Public Key Infrastructure Online
Certificate Status Protocol - OCSP
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
typedef oscp-response {
type binary;
description
"A OCSPResponse structure, as specified in RFC 6960,
encoded using ASN.1 distinguished encoding rules
(DER), as specified in ITU-T X.690.";
reference
"RFC 6960:
X.509 Internet Public Key Infrastructure Online
Certificate Status Protocol - OCSP
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
/***********************************************/
/* Typedefs for ASN.1 structures from 5652 */
/***********************************************/
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typedef cms {
type binary;
description
"A ContentInfo structure, as specified in RFC 5652,
encoded using ASN.1 distinguished encoding rules (DER),
as specified in ITU-T X.690.";
reference
"RFC 5652:
Cryptographic Message Syntax (CMS)
ITU-T X.690:
Information technology - ASN.1 encoding rules:
Specification of Basic Encoding Rules (BER),
Canonical Encoding Rules (CER) and Distinguished
Encoding Rules (DER).";
}
typedef data-content-cms {
type cms;
description
"A CMS structure whose top-most content type MUST be the
data content type, as described by Section 4 in RFC 5652.";
reference
"RFC 5652: Cryptographic Message Syntax (CMS)";
}
typedef signed-data-cms {
type cms;
description
"A CMS structure whose top-most content type MUST be the
signed-data content type, as described by Section 5 in
RFC 5652.";
reference
"RFC 5652: Cryptographic Message Syntax (CMS)";
}
typedef enveloped-data-cms {
type cms;
description
"A CMS structure whose top-most content type MUST be the
enveloped-data content type, as described by Section 6
in RFC 5652.";
reference
"RFC 5652: Cryptographic Message Syntax (CMS)";
}
typedef digested-data-cms {
type cms;
description
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"A CMS structure whose top-most content type MUST be the
digested-data content type, as described by Section 7
in RFC 5652.";
reference
"RFC 5652: Cryptographic Message Syntax (CMS)";
}
typedef encrypted-data-cms {
type cms;
description
"A CMS structure whose top-most content type MUST be the
encrypted-data content type, as described by Section 8
in RFC 5652.";
reference
"RFC 5652: Cryptographic Message Syntax (CMS)";
}
typedef authenticated-data-cms {
type cms;
description
"A CMS structure whose top-most content type MUST be the
authenticated-data content type, as described by Section 9
in RFC 5652.";
reference
"RFC 5652: Cryptographic Message Syntax (CMS)";
}
/*********************************************************/
/* Typedefs for ASN.1 structures related to RFC 5280 */
/*********************************************************/
typedef trust-anchor-cert-x509 {
type x509;
description
"A Certificate structure that MUST encode a self-signed
root certificate.";
}
typedef end-entity-cert-x509 {
type x509;
description
"A Certificate structure that MUST encode a certificate
that is neither self-signed nor having Basic constraint
CA true.";
}
/*********************************************************/
/* Typedefs for ASN.1 structures related to RFC 5652 */
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/*********************************************************/
typedef trust-anchor-cert-cms {
type signed-data-cms;
description
"A CMS SignedData structure that MUST contain the chain of
X.509 certificates needed to authenticate the certificate
presented by a client or end-entity.
The CMS MUST contain only a single chain of certificates.
The client or end-entity certificate MUST only authenticate
to last intermediate CA certificate listed in the chain.
In all cases, the chain MUST include a self-signed root
certificate. In the case where the root certificate is
itself the issuer of the client or end-entity certificate,
only one certificate is present.
This CMS structure MAY (as applicable where this type is
used) also contain suitably fresh (as defined by local
policy) revocation objects with which the device can
verify the revocation status of the certificates.
This CMS encodes the degenerate form of the SignedData
structure that is commonly used to disseminate X.509
certificates and revocation objects (RFC 5280).";
reference
"RFC 5280:
Internet X.509 Public Key Infrastructure Certificate
and Certificate Revocation List (CRL) Profile.";
}
typedef end-entity-cert-cms {
type signed-data-cms;
description
"A CMS SignedData structure that MUST contain the end
entity certificate itself, and MAY contain any number
of intermediate certificates leading up to a trust
anchor certificate. The trust anchor certificate
MAY be included as well.
The CMS MUST contain a single end entity certificate.
The CMS MUST NOT contain any spurious certificates.
This CMS structure MAY (as applicable where this type is
used) also contain suitably fresh (as defined by local
policy) revocation objects with which the device can
verify the revocation status of the certificates.
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This CMS encodes the degenerate form of the SignedData
structure that is commonly used to disseminate X.509
certificates and revocation objects (RFC 5280).";
reference
"RFC 5280:
Internet X.509 Public Key Infrastructure Certificate
and Certificate Revocation List (CRL) Profile.";
}
/*****************/
/* Groupings */
/*****************/
grouping encrypted-value-grouping {
description
"A reusable grouping for a value that has been encrypted by
a referenced symmetric or asymmetric key.";
container encrypted-by {
nacm:default-deny-write;
description
"An empty container enabling a reference to the key that
encrypted the value to be augmented in. The referenced
key MUST be a symmetric key or an asymmetric key.
A symmetric key MUST be referenced via a leaf node called
'symmetric-key-ref'. An asymmetric key MUST be referenced
via a leaf node called 'asymmetric-key-ref'.
The leaf nodes MUST be direct descendants in the data tree,
and MAY be direct descendants in the schema tree.";
}
leaf encrypted-value-format {
type identityref {
base encrypted-value-format;
}
mandatory true;
description
"Identifies the format of the 'encrypted-value' leaf.
If 'encrypted-by' points to a symmetric key, then a
'symmetrically-encrypted-value-format' based identity
MUST by set (e.g., cms-encrypted-data-format).
If 'encrypted-by' points to an asymmetric key, then an
'asymmetrically-encrypted-value-format' based identity
MUST by set (e.g., cms-enveloped-data-format).";
}
leaf encrypted-value {
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nacm:default-deny-write;
type binary;
must '../encrypted-by';
mandatory true;
description
"The value, encrypted using the referenced symmetric
or asymmetric key. The value MUST be encoded using
the format associated with the 'encrypted-value-format'
leaf.";
}
}
grouping password-grouping {
description
"A password that MAY be encrypted.";
choice password-type {
nacm:default-deny-write;
mandatory true;
description
"Choice between password types.";
case cleartext-password {
leaf cleartext-password {
nacm:default-deny-all;
type string;
description
"The cleartext value of the password.";
}
}
case encrypted-password {
if-feature "password-encryption";
container encrypted-password {
description
"A container for the encrypted password value.";
uses encrypted-value-grouping;
}
}
}
}
grouping symmetric-key-grouping {
description
"A symmetric key.";
leaf key-format {
nacm:default-deny-write;
type identityref {
base symmetric-key-format;
}
description
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"Identifies the symmetric key's format. Implementations
SHOULD ensure that the incoming symmetric key value is
encoded in the specified format.
For encrypted keys, the value is the same as it would
have been if the key were not encrypted.";
}
choice key-type {
nacm:default-deny-write;
mandatory true;
description
"Choice between key types.";
case cleartext-key {
leaf cleartext-key {
nacm:default-deny-all;
type binary;
must '../key-format';
description
"The binary value of the key. The interpretation of
the value is defined by the 'key-format' field.";
}
}
case hidden-key {
leaf hidden-key {
type empty;
must 'not(../key-format)';
description
"A hidden key. How such keys are created is outside
the scope of this module.";
}
}
case encrypted-key {
if-feature "symmetric-key-encryption";
container encrypted-key {
must '../key-format';
description
"A container for the encrypted symmetric key value.
The interpretation of the 'encrypted-value' node
is via the 'key-format' node";
uses encrypted-value-grouping;
}
}
}
}
grouping public-key-grouping {
description
"A public key.";
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leaf public-key-format {
nacm:default-deny-write;
type identityref {
base public-key-format;
}
mandatory true;
description
"Identifies the public key's format. Implementations SHOULD
ensure that the incoming public key value is encoded in the
specified format.";
}
leaf public-key {
nacm:default-deny-write;
type binary;
mandatory true;
description
"The binary value of the public key. The interpretation
of the value is defined by 'public-key-format' field.";
}
}
grouping asymmetric-key-pair-grouping {
description
"A private key and its associated public key. Implementations
SHOULD ensure that the two keys are a matching pair.";
uses public-key-grouping;
leaf private-key-format {
nacm:default-deny-write;
type identityref {
base private-key-format;
}
description
"Identifies the private key's format. Implementations SHOULD
ensure that the incoming private key value is encoded in the
specified format.
For encrypted keys, the value is the same as it would have
been if the key were not encrypted.";
}
choice private-key-type {
nacm:default-deny-write;
mandatory true;
description
"Choice between key types.";
case cleartext-private-key {
leaf cleartext-private-key {
nacm:default-deny-all;
type binary;
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must '../private-key-format';
description
"The value of the binary key The key's value is
interpreted by the 'private-key-format' field.";
}
}
case hidden-private-key {
leaf hidden-private-key {
type empty;
must 'not(../private-key-format)';
description
"A hidden key. How such keys are created is
outside the scope of this module.";
}
}
case encrypted-private-key {
if-feature "private-key-encryption";
container encrypted-private-key {
must '../private-key-format';
description
"A container for the encrypted asymmetric private key
value. The interpretation of the 'encrypted-value'
node is via the 'private-key-format' node";
uses encrypted-value-grouping;
}
}
}
}
grouping certificate-expiration-grouping {
description
"A notification for when a certificate is about to, or
already has, expired.";
notification certificate-expiration {
if-feature "certificate-expiration-notification";
description
"A notification indicating that the configured certificate
is either about to expire or has already expired. When to
send notifications is an implementation specific decision,
but it is RECOMMENDED that a notification be sent once a
month for 3 months, then once a week for four weeks, and
then once a day thereafter until the issue is resolved.";
leaf expiration-date {
type yang:date-and-time;
mandatory true;
description
"Identifies the expiration date on the certificate.";
}
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}
}
grouping trust-anchor-cert-grouping {
description
"A trust anchor certificate, and a notification for when
it is about to (or already has) expire.";
leaf cert-data {
nacm:default-deny-write;
type trust-anchor-cert-cms;
description
"The binary certificate data for this certificate.";
}
uses certificate-expiration-grouping;
}
grouping end-entity-cert-grouping {
description
"An end entity certificate, and a notification for when
it is about to (or already has) expire. Implementations
SHOULD assert that, where used, the end entity certificate
contains the expected public key.";
leaf cert-data {
nacm:default-deny-write;
type end-entity-cert-cms;
description
"The binary certificate data for this certificate.";
}
uses certificate-expiration-grouping;
}
grouping generate-csr-grouping {
description
"Defines the 'generate-certificate-signing-request' action.";
action generate-certificate-signing-request {
if-feature "certificate-signing-request-generation";
nacm:default-deny-all;
description
"Generates a certificate signing request structure for
the associated asymmetric key using the passed subject
and attribute values.
This action statement is only available when the
associated 'public-key-format' node's value is
'subject-public-key-info-format'.";
reference
"RFC 6125:
Representation and Verification of Domain-Based
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Application Service Identity within Internet Public Key
Infrastructure Using X.509 (PKIX) Certificates in the
Context of Transport Layer Security (TLS)";
input {
leaf csr-info {
type ct:csr-info;
mandatory true;
description
"A CertificationRequestInfo structure, as defined in
RFC 2986.
Enables the client to provide a fully-populated
CertificationRequestInfo structure that the server
only needs to sign in order to generate the complete
'CertificationRequest' structure to return in the
'output'.
The 'AlgorithmIdentifier' field contained inside
the 'SubjectPublicKeyInfo' field MUST be one known
to be supported by the device.";
reference
"RFC 2986:
PKCS #10: Certification Request Syntax Specification
RFC AAAA:
YANG Data Types and Groupings for Cryptography";
}
}
output {
leaf certificate-signing-request {
type ct:csr;
mandatory true;
description
"A CertificationRequest structure, as defined in
RFC 2986.";
reference
"RFC 2986:
PKCS #10: Certification Request Syntax Specification
RFC AAAA:
YANG Data Types and Groupings for Cryptography";
}
}
}
} // generate-csr-grouping
grouping asymmetric-key-pair-with-cert-grouping {
description
"A private/public key pair and an associated certificate.
Implementations SHOULD assert that certificates contain
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the matching public key.";
uses asymmetric-key-pair-grouping;
uses end-entity-cert-grouping;
uses generate-csr-grouping;
} // asymmetric-key-pair-with-cert-grouping
grouping asymmetric-key-pair-with-certs-grouping {
description
"A private/public key pair and associated certificates.
Implementations SHOULD assert that certificates contain
the matching public key.";
uses asymmetric-key-pair-grouping;
container certificates {
nacm:default-deny-write;
description
"Certificates associated with this asymmetric key.";
list certificate {
key "name";
description
"A certificate for this asymmetric key.";
leaf name {
type string;
description
"An arbitrary name for the certificate.";
}
uses end-entity-cert-grouping {
refine "cert-data" {
mandatory true;
}
}
}
}
uses generate-csr-grouping;
} // asymmetric-key-pair-with-certs-grouping
}
<CODE ENDS>
3. Security Considerations
3.1. No Support for CRMF
This document uses PKCS #10 [RFC2986] for the "generate-certificate-
signing-request" action. The use of Certificate Request Message
Format (CRMF) [RFC4211] was considered, but it was unclear if there
was market demand for it. If it is desired to support CRMF in the
future, a backwards compatible solution can be defined at that time.
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3.2. No Support for Key Generation
Early revisions of this document included "rpc" statements for
generating symmetric and asymmetric keys. These statements were
removed due to an inability to obtain consensus for how to identify
the key-algorithm to use. Thusly, the solution presented in this
document only supports keys to be configured via an external client,
which does not support Security best practice.
3.3. Unconstrained Public Key Usage
This module defines the "public-key-grouping" grouping, which enables
the configuration of public keys without constraints on their usage,
e.g., what operations the key is allowed to be used for (encryption,
verification, both).
The "asymmetric-key-pair-grouping" grouping uses the aforementioned
"public-key-grouping" grouping, and carries the same traits.
The "asymmetric-key-pair-with-cert-grouping" grouping uses the
aforementioned "asymmetric-key-pair-grouping" grouping, whereby each
certificate may constrain the usage of the public key according to
local policy.
3.4. Unconstrained Private Key Usage
This module defines the "asymmetric-key-pair-grouping" grouping,
which 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).
The "asymmetric-key-pair-with-cert-grouping" uses the aforementioned
"asymmetric-key-pair-grouping" grouping, whereby configured
certificates (e.g., identity certificates) may constrain the use of
the public key according to local policy.
3.5. Strength of Keys Conveyed
When accessing key values, it is desireable that implementations
ensure that the strength of the keys being accessed is not greater
than the strength of the underlying secure transport connection over
which the keys are conveyed. However, comparing key strengths can be
complicated and difficult to implement in practice.
That said, expert Security opinion suggests that already it is
infeasible to break a 128-bit symmetric key using a classical
computer, and thus the concern for conveying higher-strength keys
begins to lose its allure.
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Implementations SHOULD only use secure transport protocols meeting
local policy. A reasonable policy may, e.g., state that only
ciphersuites listed as "recommended" by the IETF be used (e.g.,
[RFC7525] for TLS).
3.6. Encrypting Passwords
The module contained within this document enables passwords to be
encrypted. Passwords may be encrypted via a symmetric key using the
"cms-encrypted-data-format" format. This format uses the CMS
EncryptedData structure, which allows any encryption algorithm to be
used.
In order to thwart rainbow attacks, algorithms that result in a
unique output for the same input SHOULD NOT be used. For instance,
AES using "ECB" SHOULD NOT be used to encrypt passwords, whereas
"CBC" mode is permissible since an unpredictable initialization
vector (IV) MUST be used for each use.
3.7. Deletion of Cleartext Key Values
This module defines storage for cleartext key values that SHOULD be
zeroized when deleted, so as to prevent the remnants of their
persisted storage locations from being analyzed in any meaningful
way.
The cleartext key values are the "cleartext-key" node defined in the
"symmetric-key-grouping" grouping (Section 2.1.4.3) and the
"cleartext-private-key" node defined in the "asymmetric-key-pair-
grouping" grouping ("Section 2.1.4.5).
3.8. The "ietf-crypto-types" YANG Module
The YANG module in this document defines "grouping" statements that
are 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 NETCONF 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.
Since the module in this document only defines groupings, these
considerations are primarily for the designers of other modules that
use these groupings.
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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. These are the subtrees and
data nodes and their sensitivity/vulnerability:
* The "cleartext-key" node:
The "cleartext-key" node defined in the "symmetric-key-
grouping" grouping 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" has been applied to it.
* The "cleartext-private-key" node:
The "cleartext-private-key" node defined in the "asymmetric-
key-pair-grouping" grouping 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" has been applied.
* The "cert-data" node:
The "cert-data" node, defined in both the "trust-anchor-cert-
grouping" and "end-entity-cert-grouping" groupings, is
additionally sensitive to read operations, as certificates
sometimes convey personally identifying information (especially
end-entity certificates). However, as it is commonly
understood that certificates are "public", the NACM extension
"nacm:default-deny-write" (not "default-deny-all") has been
applied. It is RECOMMENDED that implementations adjust read-
access to certificates to comply with local policy.
All the writable data nodes defined by all the groupings defined in
this module may be considered sensitive or vulnerable in some network
environments. For instance, even the modification of a public key or
a certificate can dramatically alter the implemented security policy.
For this reason, the NACM extension "default-deny-write" has been
applied to all the data nodes defined in the module.
Some of the operations in this YANG module may be considered
sensitive or vulnerable in some network environments. It is thus
important to control access to these operations. These are the
operations and their sensitivity/vulnerability:
* generate-certificate-signing-request:
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This "action" statement SHOULD only be executed by authorized
users. For this reason, the NACM extension "default-deny-all"
has been applied. Note that NACM uses "default-deny-all" to
protect "RPC" and "action" statements; it does not define,
e.g., an extension called "default-deny-execute".
For this action, it is RECOMMENDED that implementations assert
channel binding [RFC5056], so as to ensure that the application
layer that sent the request is the same as the device
authenticated when the secure transport layer was established.
4. IANA Considerations
4.1. 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-crypto-types
Registrant Contact: The IESG
XML: N/A, the requested URI is an XML namespace.
4.2. 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-crypto-types
namespace: urn:ietf:params:xml:ns:yang:ietf-crypto-types
prefix: ct
reference: RFC AAAA
5. References
5.1. Normative References
[ITU.X680.2015]
International Telecommunication Union, "Information
technology - Abstract Syntax Notation One (ASN.1):
Specification of basic notation", ITU-T Recommendation
X.680, ISO/IEC 8824-1:2015, August 2015,
<https://www.itu.int/rec/T-REC-X.680/>.
[ITU.X690.2015]
International Telecommunication Union, "Information
Technology - ASN.1 encoding rules: Specification of Basic
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Encoding Rules (BER), Canonical Encoding Rules (CER) and
Distinguished Encoding Rules (DER)", ITU-T Recommendation
X.690, ISO/IEC 8825-1:2015, August 2015,
<https://www.itu.int/rec/T-REC-X.690/>.
[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>.
[RFC3447] Jonsson, J. and B. Kaliski, "Public-Key Cryptography
Standards (PKCS) #1: RSA Cryptography Specifications
Version 2.1", RFC 3447, DOI 10.17487/RFC3447, February
2003, <https://www.rfc-editor.org/info/rfc3447>.
[RFC4253] Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH)
Transport Layer Protocol", RFC 4253, DOI 10.17487/RFC4253,
January 2006, <https://www.rfc-editor.org/info/rfc4253>.
[RFC5280] Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
Housley, R., and W. Polk, "Internet X.509 Public Key
Infrastructure Certificate and Certificate Revocation List
(CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
<https://www.rfc-editor.org/info/rfc5280>.
[RFC5652] Housley, R., "Cryptographic Message Syntax (CMS)", STD 70,
RFC 5652, DOI 10.17487/RFC5652, September 2009,
<https://www.rfc-editor.org/info/rfc5652>.
[RFC5958] Turner, S., "Asymmetric Key Packages", RFC 5958,
DOI 10.17487/RFC5958, August 2010,
<https://www.rfc-editor.org/info/rfc5958>.
[RFC6031] Turner, S. and R. Housley, "Cryptographic Message Syntax
(CMS) Symmetric Key Package Content Type", RFC 6031,
DOI 10.17487/RFC6031, December 2010,
<https://www.rfc-editor.org/info/rfc6031>.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/info/rfc6991>.
[RFC7093] Turner, S., Kent, S., and J. Manger, "Additional Methods
for Generating Key Identifiers Values", RFC 7093,
DOI 10.17487/RFC7093, December 2013,
<https://www.rfc-editor.org/info/rfc7093>.
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[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>.
[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>.
[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>.
5.2. Informative 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-20, 18 May 2021,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
crypto-types-20>.
[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-07, 18 May 2021,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
http-client-server-07>.
[I-D.ietf-netconf-keystore]
Watsen, K., "A YANG Data Model for a Keystore", Work in
Progress, Internet-Draft, draft-ietf-netconf-keystore-22,
18 May 2021, <https://datatracker.ietf.org/doc/html/draft-
ietf-netconf-keystore-22>.
[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-23, 18 May 2021,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
netconf-client-server-23>.
[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-23, 18 May 2021,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
restconf-client-server-23>.
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[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-25, 18 June 2021,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
ssh-client-server-25>.
[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-10, 18 May 2021,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
tcp-client-server-10>.
[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-25, 18 June 2021,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
tls-client-server-25>.
[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-15, 18 May 2021,
<https://datatracker.ietf.org/doc/html/draft-ietf-netconf-
trust-anchors-15>.
[RFC2986] Nystrom, M. and B. Kaliski, "PKCS #10: Certification
Request Syntax Specification Version 1.7", RFC 2986,
DOI 10.17487/RFC2986, November 2000,
<https://www.rfc-editor.org/info/rfc2986>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/info/rfc3688>.
[RFC4211] Schaad, J., "Internet X.509 Public Key Infrastructure
Certificate Request Message Format (CRMF)", RFC 4211,
DOI 10.17487/RFC4211, September 2005,
<https://www.rfc-editor.org/info/rfc4211>.
[RFC5056] Williams, N., "On the Use of Channel Bindings to Secure
Channels", RFC 5056, DOI 10.17487/RFC5056, November 2007,
<https://www.rfc-editor.org/info/rfc5056>.
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[RFC5915] Turner, S. and D. Brown, "Elliptic Curve Private Key
Structure", RFC 5915, DOI 10.17487/RFC5915, June 2010,
<https://www.rfc-editor.org/info/rfc5915>.
[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>.
[RFC6125] Saint-Andre, P. and J. Hodges, "Representation and
Verification of Domain-Based Application Service Identity
within Internet Public Key Infrastructure Using X.509
(PKIX) Certificates in the Context of Transport Layer
Security (TLS)", RFC 6125, DOI 10.17487/RFC6125, March
2011, <https://www.rfc-editor.org/info/rfc6125>.
[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>.
[RFC7525] Sheffer, Y., Holz, R., and P. Saint-Andre,
"Recommendations for Secure Use of Transport Layer
Security (TLS) and Datagram Transport Layer Security
(DTLS)", BCP 195, RFC 7525, DOI 10.17487/RFC7525, May
2015, <https://www.rfc-editor.org/info/rfc7525>.
[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>.
[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>.
Appendix A. Change Log
This section is to be removed before publishing as an RFC.
A.1. I-D to 00
* Removed groupings and notifications.
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* Added typedefs for identityrefs.
* Added typedefs for other RFC 5280 structures.
* Added typedefs for other RFC 5652 structures.
* Added convenience typedefs for RFC 4253, RFC 5280, and RFC 5652.
A.2. 00 to 01
* Moved groupings from the draft-ietf-netconf-keystore here.
A.3. 01 to 02
* Removed unwanted "mandatory" and "must" statements.
* Added many new crypto algorithms (thanks Haiguang!)
* Clarified in asymmetric-key-pair-with-certs-grouping, in
certificates/certificate/name/description, that if the name MUST
NOT match the name of a certificate that exists independently in
<operational>, enabling certs installed by the manufacturer (e.g.,
an IDevID).
A.4. 02 to 03
* renamed base identity 'asymmetric-key-encryption-algorithm' to
'asymmetric-key-algorithm'.
* added new 'asymmetric-key-algorithm' identities for secp192r1,
secp224r1, secp256r1, secp384r1, and secp521r1.
* removed 'mac-algorithm' identities for mac-aes-128-ccm, mac-aes-
192-ccm, mac-aes-256-ccm, mac-aes-128-gcm, mac-aes-192-gcm, mac-
aes-256-gcm, and mac-chacha20-poly1305.
* for all -cbc and -ctr identities, renamed base identity
'symmetric-key-encryption-algorithm' to 'encryption-algorithm'.
* for all -ccm and -gcm identities, renamed base identity
'symmetric-key-encryption-algorithm' to 'encryption-and-mac-
algorithm' and renamed the identity to remove the "enc-" prefix.
* for all the 'signature-algorithm' based identities, renamed from
'rsa-*' to 'rsassa-*'.
* removed all of the "x509v3-" prefixed 'signature-algorithm' based
identities.
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* added 'key-exchange-algorithm' based identities for 'rsaes-oaep'
and 'rsaes-pkcs1-v1_5'.
* renamed typedef 'symmetric-key-encryption-algorithm-ref' to
'symmetric-key-algorithm-ref'.
* renamed typedef 'asymmetric-key-encryption-algorithm-ref' to
'asymmetric-key-algorithm-ref'.
* added typedef 'encryption-and-mac-algorithm-ref'.
* Updated copyright date, boilerplate template, affiliation, and
folding algorithm.
A.5. 03 to 04
* ran YANG module through formatter.
A.6. 04 to 05
* fixed broken symlink causing reformatted YANG module to not show.
A.7. 05 to 06
* Added NACM annotations.
* Updated Security Considerations section.
* Added 'asymmetric-key-pair-with-cert-grouping' grouping.
* Removed text from 'permanently-hidden' enum regarding such keys
not being backed up or restored.
* Updated the boilerplate text in module-level "description"
statement to match copyeditor convention.
* Added an explanation to the 'public-key-grouping' and 'asymmetric-
key-pair-grouping' statements as for why the nodes are not
mandatory (e.g., because they may exist only in <operational>.
* Added 'must' expressions to the 'public-key-grouping' and
'asymmetric-key-pair-grouping' statements ensuring sibling nodes
are either all exist or do not all exist.
* Added an explanation to the 'permanently-hidden' that the value
cannot be configured directly by clients and servers MUST fail any
attempt to do so.
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* Added 'trust-anchor-certs-grouping' and 'end-entity-certs-
grouping' (the plural form of existing groupings).
* Now states that keys created in <operational> by the *-hidden-key
actions are bound to the lifetime of the parent 'config true'
node, and that subsequent invocations of either action results in
a failure.
A.8. 06 to 07
* Added clarifications that implementations SHOULD assert that
configured certificates contain the matching public key.
* Replaced the 'generate-hidden-key' and 'install-hidden-key'
actions with special 'crypt-hash' -like input/output values.
A.9. 07 to 08
* Removed the 'generate-key and 'hidden-key' features.
* Added grouping symmetric-key-grouping
* Modified 'asymmetric-key-pair-grouping' to have a 'choice'
statement for the keystone module to augment into, as well as
replacing the 'union' with leafs (having different NACM settings.
A.10. 08 to 09
* Converting algorithm from identities to enumerations.
A.11. 09 to 10
* All the below changes are to the algorithm enumerations defined in
ietf-crypto-types.
* Add in support for key exchange over x.25519 and x.448 based on
RFC 8418.
* Add in SHAKE-128, SHAKE-224, SHAKE-256, SHAKE-384 and SHAKE 512
* Revise/add in enum of signature algorithm for x25519 and x448
* Add in des3-cbc-sha1 for IPSec
* Add in sha1-des3-kd for IPSec
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* Add in definit for rc4-hmac and rc4-hmac-exp. These two
algorithms have been deprecated in RFC 8429. But some existing
draft in i2nsf may still want to use them.
* Add x25519 and x448 curve for asymmetric algorithms
* Add signature algorithms ed25519, ed25519-cts, ed25519ph
* add signature algorithms ed448, ed448ph
* Add in rsa-sha2-256 and rsa-sha2-512 for SSH protocols (rfc8332)
A.12. 10 to 11
* Added a "key-format" identity.
* Added symmetric keys to the example in Section 2.2.
A.13. 11 to 12
* Removed all non-essential (to NC/RC) algorithm types.
* Moved remaining algorithm types each into its own module.
* Added a 'config false' "algorithms-supported" list to each of the
algorithm-type modules.
A.14. 12 to 13
* Added the four features: "[encrypted-]one-[a]symmetric-key-
format", each protecting a 'key-format' identity of the same name.
* Added 'must' expressions asserting that the 'key-format' leaf
exists whenever a non-hidden key is specified.
* Improved the 'description' statements and added 'reference'
statements for the 'key-format' identities.
* Added a questionable forward reference to "encrypted-*" leafs in a
couple 'when' expressions.
* Did NOT move "config false" alg-supported lists to SSH/TLS drafts.
A.15. 13 to 14
* Resolved the "FIXME: forward ref" issue by modulating 'must',
'when', and 'mandatory' expressions.
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* Moved the 'generatesymmetric-key' and 'generate-asymmetric-key'
actions from ietf-keystore to ietf-crypto-types, now as RPCs.
* Cleaned up various description statements and removed lingering
FIXMEs.
* Converted the "iana-<alg-type>-algs" YANG modules to IANA
registries with instructions for how to generate modules from the
registries, whenever they may be updated.
A.16. 14 to 15
* Removed the IANA-maintained registries for symmetric, asymmetric,
and hash algorithms.
* Removed the "generate-symmetric-key" and "generate-asymmetric-key"
RPCs.
* Removed the "algorithm" node in the various symmetric and
asymmetric key groupings.
* Added 'typedef csr' and 'feature certificate-signing-request-
generation'.
* Refined a usage of "end-entity-cert-grouping" to make the "cert"
node mandatory true.
* Added a "Note to Reviewers" note to first page.
A.17. 15 to 16
* Updated draft title (refer to "Groupings" too).
* Removed 'end-entity-certs-grouping' as it wasn't being used
anywhere.
* Removed 'trust-anchor-certs-grouping' as it was no longer being
used after modifying 'local-or-truststore-certs-grouping' to use
lists (not leaf-lists).
* Renamed "cert" to "cert-data" in trust-anchor-cert-grouping.
* Added "csr-info" typedef, to complement the existing "csr"
typedef.
* Added "ocsp-request" and "ocsp-response" typedefs, to complement
the existing "crl" typedef.
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* Added "encrypted" cases to both symmetric-key-grouping and
asymmetric-key-pair-grouping (Moved from Keystore draft).
* Expanded "Data Model Overview section(s) [remove "wall" of tree
diagrams].
* Updated the Security Considerations section.
A.18. 16 to 17
* [Re]-added a "Strength of Keys Configured" Security Consideration
* Prefixed "cleartext-" in the "key" and "private-key" node names.
A.19. 17 to 18
* Fixed issues found by the SecDir review of the "keystore" draft.
* Added "password-grouping", discussed during the IETF 108 session.
A.20. 18 to 19
* Added a "Unconstrained Public Key Usage" Security Consideration to
address concern raised by SecDir of the 'truststore' draft.
* Added a "Unconstrained Private Key Usage" Security Consideration
to address concern raised by SecDir of the 'truststore' draft.
* Changed the encryption strategy, after conferring with Russ
Housley.
* Added a "password-grouping" example to the "crypto-types-usage"
example.
* Added an "Encrypting Passwords" section to Security Consideration.
* Addressed other comments raised by YANG Doctor.
A.21. 19 to 20
* Nits found via YANG Doctors reviews.
* Aligned modules with `pyang -f` formatting.
A.22. 20 to 21
* Replaced "base64encodedvalue==" with "BASE64VALUE=".
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* Accommodated SecDir review by Valery Smyslov.
Acknowledgements
The authors would like to thank for following for lively discussions
on list and in the halls (ordered by first name): Balazs Kovacs, Eric
Voit, Juergen Schoenwaelder, Liang Xia, Martin Bjoerklund, Nick
Hancock, Rich Salz, Rob Wilton, Russ Housley, Sandra Murphy, Tom
Petch, Valery Smyslov, and Wang Haiguang.
Author's Address
Kent Watsen
Watsen Networks
Email: kent+ietf@watsen.net
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