A YANG Data Model for Terminal Access Controller Access-Control System Plus (TACACS+)
draft-ietf-opsawg-secure-tacacs-yang-01
| Document | Type | Active Internet-Draft (opsawg WG) | |
|---|---|---|---|
| Authors | Mohamed Boucadair , Bo Wu , Guangying Zheng , Zitao Wang | ||
| Last updated | 2024-12-11 | ||
| Replaces | draft-boucadair-opsawg-secure-tacacs-yang | ||
| RFC stream | Internet Engineering Task Force (IETF) | ||
| Intended RFC status | (None) | ||
| Formats | |||
| Yang Validation | 0 errors, 0 warnings | ||
| Additional resources |
GitHub Repository
Mailing list discussion |
||
| Stream | WG state | WG Document | |
| Document shepherd | (None) | ||
| IESG | IESG state | I-D Exists | |
| Consensus boilerplate | Unknown | ||
| Telechat date | (None) | ||
| Responsible AD | (None) | ||
| Send notices to | (None) |
draft-ietf-opsawg-secure-tacacs-yang-01
Operations and Management Area Working Group M. Boucadair, Ed.
Internet-Draft Orange
Obsoletes: 9105 (if approved) B. Wu
Intended status: Standards Track G. Zheng
Expires: 14 June 2025 M. Wang
Huawei Technologies
11 December 2024
A YANG Data Model for Terminal Access Controller Access-Control System
Plus (TACACS+)
draft-ietf-opsawg-secure-tacacs-yang-01
Abstract
This document defines a Terminal Access Controller Access-Control
System Plus (TACACS+) client YANG module that augments the System
Management data model, defined in RFC 7317, to allow devices to make
use of TACACS+ servers for centralized Authentication, Authorization,
and Accounting (AAA). Specifically, this document defines a YANG
module for TACACS+ over TLS 1.3.
This document obsoletes RFC 9105.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF). Note that other groups may also distribute
working documents as Internet-Drafts. The list of current Internet-
Drafts is at https://datatracker.ietf.org/drafts/current/.
Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time. It is inappropriate to use Internet-Drafts as reference
material or to cite them other than as "work in progress."
This Internet-Draft will expire on 14 June 2025.
Copyright Notice
Copyright (c) 2024 IETF Trust and the persons identified as the
document authors. All rights reserved.
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This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents (https://trustee.ietf.org/
license-info) in effect on the date of publication of this document.
Please review these documents carefully, as they describe your rights
and restrictions with respect to this document. Code Components
extracted from this document must include Revised BSD License text as
described in Section 4.e of the Trust Legal Provisions and are
provided without warranty as described in the Revised BSD License.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Changes Since RFC 9105 . . . . . . . . . . . . . . . . . 2
2. Conventions and Definitions . . . . . . . . . . . . . . . . . 3
2.1. Tree Diagrams . . . . . . . . . . . . . . . . . . . . . . 3
3. Design of the TACACS+ Data Model . . . . . . . . . . . . . . 3
4. TACACS+ Client Module . . . . . . . . . . . . . . . . . . . . 7
5. Security Considerations . . . . . . . . . . . . . . . . . . . 23
6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 24
7. References . . . . . . . . . . . . . . . . . . . . . . . . . 24
7.1. Normative References . . . . . . . . . . . . . . . . . . 24
7.2. Informative References . . . . . . . . . . . . . . . . . 27
Appendix A. Full Tree . . . . . . . . . . . . . . . . . . . . . 27
Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . 38
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 38
1. Introduction
[RFC9105] defines a YANG module ("ietf-system-tacacs-plus") that
augments the System Management data model defined in [RFC7317] for
the management of Terminal Access Controller Access-Control System
Plus (TACACS+) clients. Typically, the "ietf-system-tacacs-plus"
module is used to configure a TACACS+ client on a device to support
deployment scenarios with centralized authentication, authorization,
and accounting servers.
This document defines a YANG module for managing TACACS+ client,
including TACACS+ over TLS 1.3 clients
[I-D.ietf-opsawg-tacacs-tls13]. This document obsoletes [RFC9105].
The YANG module in this document conforms to the Network Management
Datastore Architecture (NMDA) defined in [RFC8342].
1.1. Changes Since RFC 9105
The following changes have been made to [RFC9105]:
* Add support for TLS
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2. Conventions and Definitions
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.
The terminology for describing YANG data models is defined in
[RFC7950].
The document uses the terms defined in Section 2 of
[I-D.ietf-opsawg-tacacs-tls13] and Section 3 of [RFC8907].
'client' refers to TACACS+ client, while 'server' refers to TACACS+
server.
2.1. Tree Diagrams
The tree diagram used in this document follows the notation defined
in [RFC8340].
3. Design of the TACACS+ Data Model
This module is used to configure a TACACS+ client on a device to
support deployment scenarios with centralized authentication,
authorization, and accounting servers. Authentication is used to
validate a user's username and password, authorization allows the
user to access and execute commands at various privilege levels
assigned to the user, and accounting keeps track of the activity of a
user who has accessed the device.
The ietf-system-tacacs-plus module augments the "/sys:system" path
defined in the ietf-system module with the contents of the "tacacs-
plus" grouping. Therefore, a device can use local, RADIUS, or
TACACS+ authentication to validate users who attempt to access the
router by several mechanisms, e.g., a command line interface or a
web-based user interface.
The "server" list, which is directly under the "tacacs-plus"
container, holds a list of TACACS+ servers and uses server-type to
distinguish between Authentication, Authorization, and Accounting
(AAA) services. The list of servers is for redundancy.
When there are multiple interfaces connected to the TACACS+ client or
server, the source address of outgoing TACACS+ packets could be
specified, or the source address could be specified through the
interface IP address setting or derived from the outbound interface
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from the local Forwarding Information Base (FIB). For the TACACS+
server located in a Virtual Private Network (VPN), a VPN Routing and
Forwarding (VRF) instance needs to be specified.
The "statistics" container under the "server list" is a collection of
read-only counters for sent and received messages from a configured
server.
The YANG module for TACACS+ client has the following structure:
=============== NOTE: '\' line wrapping per RFC 8792 ================
module: ietf-system-tacacs-plus
augment /sys:system:
+--rw tacacs-plus
+--rw client-credentials* [id] {credential-reference}?
| +--rw id string
| +--rw (auth-type)?
| +--:(certificate)
| | ...
| +--:(raw-public-key) {tlsc:client-ident-raw-public-key}?
| | ...
| +--:(tls13-epsk) {tlsc:client-ident-tls13-epsk}?
| ...
+--rw server-credentials* [id] {credential-reference}?
| +--rw id string
| +--rw ca-certs!
| | ...
| +--rw ee-certs!
| | ...
| +--rw raw-public-keys! {tlsc:server-auth-raw-public-key}?
| | ...
| +--rw tls13-epsks? empty
| {tlsc:server-auth-tls13-epsk}?
+--rw server* [name]
+--rw name string
+--rw server-type
| tacacs-plus-server-type
+--rw domain-name? inet:domain-name
+--rw address inet:host
+--rw port? inet:port-number
+--rw (security)
| +--:(tls)
| | +--rw client-identity!
| | | +--rw (ref-or-explicit)?
| | | +--:(ref)
| | | | +--rw credentials-reference?
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| | | | sys-tcs-plus:client-credentials-ref
| | | | {credential-reference}?
| | | +--:(explicit)
| | | +--rw (auth-type)?
| | | +--:(certificate)
| | | | ...
| | | +--:(raw-public-key)
| | | | {tlsc:client-ident-raw-public-\
key}?
| | | | ...
| | | +--:(tls13-epsk)
| | | {tlsc:client-ident-tls13-epsk}?
| | | ...
| | +--rw server-authentication
| | | +--rw (ref-or-explicit)?
| | | +--:(ref)
| | | | +--rw credentials-reference?
| | | | sys-tcs-plus:server-credentials-ref
| | | | {credential-reference}?
| | | +--:(explicit)
| | | +--rw ca-certs!
| | | | ...
| | | +--rw ee-certs!
| | | | ...
| | | +--rw raw-public-keys!
| | | | {tlsc:server-auth-raw-public-key}?
| | | | ...
| | | +--rw tls13-epsks? empty
| | | {tlsc:server-auth-tls13-epsk}
| | +--rw hello-params {tlscmn:hello-params}?
| | +--rw tls-versions
| | | +--rw min? identityref
| | | +--rw max? identityref
| | +--rw cipher-suites
| | +--rw cipher-suite*
| | tlscsa:tls-cipher-suite-algorithm
| +--:(obfuscation)
| +--rw shared-secret? string
+--rw (source-type)?
| +--:(source-ip)
| | +--rw source-ip? inet:ip-address
| +--:(source-interface)
| +--rw source-interface? if:interface-ref
+--rw vrf-instance?
| -> /ni:network-instances/network-instance/name
+--rw single-connection? boolean
+--rw timeout? uint16
+--ro statistics
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+--ro connection-opens? yang:counter64
+--ro connection-closes? yang:counter64
+--ro connection-aborts? yang:counter64
+--ro connection-failures? yang:counter64
+--ro connection-timeouts? yang:counter64
+--ro messages-sent? yang:counter64
+--ro messages-received? yang:counter64
+--ro errors-received? yang:counter64
+--ro sessions? yang:counter64
The module is designed to cover the following key requirements
specified in [I-D.ietf-opsawg-tacacs-tls13]:
* TLS 1.3 [RFC8446] MUST be used for transport.
* Earlier TLS versions TLS MUST NOT be used.
* The cipher suites offered or accepted SHOULD be configurable.
* Implementations MAY support Raw Public Keys and PSK.
* Implementations MUST support the ability to configure the server's
domain name
The following new data nodes are supported compared to [RFC9105]:
'client-credentials' and 'server-credentials': Defines a set
credentials that can be globally provisioned and then referenced
under specific servers.
'domain-name': Provides a domain name of the server per Section 3.3
of [I-D.ietf-opsawg-tacacs-tls13].
'client-identity': Specifies the identity credentials that the
client may present when establishing a connection to a server.
Client identities can be configured at the top level and then
referenced for specific server instances. Alternatively, client
identities can be configured explicitely under each server
instance.
'server-authentication': Specifies how a client authenticates
servers. Server credentials can be configured at the top level
and then referenced for specific server instances. Alternatively,
client identities can be configured explicitely under each server
instance.
'hello-params': Controls TLS versions and cipher suites.
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'keepalives': Providers a set of parameters for testing the
aliveness of the server.
4. TACACS+ Client Module
This module uses types and groupings defined in [RFC6991], [RFC8341],
[RFC8343], [RFC8529], [RFC9640], [RFC9641], [RFC9642], and [RFC9645].
The module augments [RFC7317].
The module also cites [RFC9257], [RFC9258], [RFC9258], and [RFC6520].
<CODE BEGINS> file "ietf-system-tacacs-plus@2024-12-11.yang"
module ietf-system-tacacs-plus {
yang-version 1.1;
namespace "urn:ietf:params:xml:ns:yang:ietf-system-tacacs-plus";
prefix sys-tcs-plus;
import ietf-inet-types {
prefix inet;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-yang-types {
prefix yang;
reference
"RFC 6991: Common YANG Data Types";
}
import ietf-system {
prefix sys;
reference
"RFC 7317: A YANG Data Model for System Management";
}
import ietf-interfaces {
prefix if;
reference
"RFC 8343: A YANG Data Model for Interface Management";
}
import ietf-netconf-acm {
prefix nacm;
reference
"RFC 8341: Network Configuration Access Control Model";
}
import ietf-network-instance {
prefix ni;
reference
"RFC 8529: YANG Data Model for Network Instances";
}
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import ietf-crypto-types {
prefix ct;
reference
"RFC 9640: YANG Data Types and Groupings for Cryptography";
}
import ietf-truststore {
prefix ts;
reference
"RFC 9641: A YANG Data Model for a Truststore";
}
import ietf-keystore {
prefix ks;
reference
"RFC 9642: A YANG Data Model for a Keystore";
}
import ietf-tls-common {
prefix tlscmn;
reference
"RFC 9645: YANG Groupings for TLS Clients and TLS Servers";
}
import ietf-tls-client {
prefix tlsc;
reference
"RFC 9645: YANG Groupings for TLS Clients and TLS Servers";
}
organization
"IETF OPSAWG (Operations and Management Area Working Group)";
contact
"WG Web: <https://datatracker.ietf.org/wg/opsawg/>
WG List: <mailto:opsawg@ietf.org>
Editor: Mohamed Boucadair
<mailto:mohamed.boucadair@orange.com>
Author: Bo Wu
<lana.wubo@huawei.com>
Author: Guangying Zheng
<zhengguangying@huawei.com>";
description
"This module provides configuration of TACACS+ clients.
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.
Copyright (c) 2024 IETF Trust and the persons identified as
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authors of the code. All rights reserved.
Redistribution and use in source and binary forms, with or
without modification, is permitted pursuant to, and subject
to the license terms contained in, the Revised BSD License
set forth in Section 4.c of the IETF Trust's Legal Provisions
Relating to IETF Documents
(https://trustee.ietf.org/license-info).
This version of this YANG module is part of RFC XXXX; see the
RFC itself for full legal notices.";
revision 2024-12-11 {
description
"This revision adds TLS support";
reference
"RFC XXXX: A YANG Model for Terminal Access Controller
Access-Control System Plus (TACACS+)";
}
revision 2021-08-05 {
description
"Initial revision.";
reference
"RFC 9105: A YANG Data Model for Terminal Access Controller
Access-Control System Plus (TACACS+)";
}
feature credential-reference {
description
"Indicates whether service credentials references are
supported.";
}
identity tacacs-plus {
base sys:authentication-method;
description
"Indicates AAA operation using TACACS+.";
}
typedef tacacs-plus-server-type {
type bits {
bit authentication {
description
"Indicates that the TACACS+ server is providing
authentication services.";
}
bit authorization {
description
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"Indicates that the TACACS+ server is providing
authorization services.";
}
bit accounting {
description
"Indicates that the TACACS+ server is providing accounting
services.";
}
}
description
"tacacs-plus-server-type can be set to
authentication/authorization/accounting
or any combination of the three types.";
}
typedef client-credentials-ref {
type leafref {
path "/sys:system/sys-tcs-plus:tacacs-plus"
+ "/sys-tcs-plus:client-credentials/sys-tcs-plus:id";
}
description
"Defines a type to reference client credentials.";
}
typedef server-credentials-ref {
type leafref {
path "/sys:system/sys-tcs-plus:tacacs-plus"
+ "/sys-tcs-plus:server-credentials/sys-tcs-plus:id";
}
description
"Defines a type to reference server credentials.";
}
grouping statistics {
description
"Grouping for TACACS+ statistics attributes.";
container statistics {
config false;
description
"A collection of server-related statistics objects.";
leaf connection-opens {
type yang:counter64;
description
"Number of new connection requests sent to the server,
e.g., socket open.";
}
leaf connection-closes {
type yang:counter64;
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description
"Number of connection close requests sent to the server,
e.g., socket close.";
}
leaf connection-aborts {
type yang:counter64;
description
"Number of aborted connections to the server. These do
not include connections that are closed gracefully.";
}
leaf connection-failures {
type yang:counter64;
description
"Number of connection failures to the server.";
}
leaf connection-timeouts {
type yang:counter64;
description
"Number of connection timeouts to the server.";
}
leaf messages-sent {
type yang:counter64;
description
"Number of messages sent to the server.";
}
leaf messages-received {
type yang:counter64;
description
"Number of messages received from the server.";
}
leaf errors-received {
type yang:counter64;
description
"Number of error messages received from the server.";
}
leaf sessions {
type yang:counter64;
description
"Number of TACACS+ sessions completed with the server.
If the Single Connection Mode was NOT enabled, the number
of sessions is the same as the number of
'connection-closes'. If the Mode was enabled, a single
TCP connection may contain multiple TACACS+ sessions.";
}
}
}
grouping certificate {
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description
"Specifies the client identity using a certificate.";
uses "ks:inline-or-keystore-end-entity-cert-with-key-"
+ "grouping" {
refine "inline-or-keystore/inline/inline-definition" {
must 'not(public-key-format) or derived-from-or-self'
+ '(public-key-format, "ct:subject-public-key-'
+ 'info-format")';
}
refine "inline-or-keystore/central-keystore/"
+ "central-keystore-reference/asymmetric-key" {
must 'not(deref(.)/../ks:public-key-format) or '
+ 'derived-from-or-self(deref(.)/../ks:public-'
+ 'key-format, "ct:subject-public-key-info-'
+ 'format")';
}
}
}
grouping raw-private-key {
description
"Specifies the client identity using a raw private
key.";
uses ks:inline-or-keystore-asymmetric-key-grouping {
refine "inline-or-keystore/inline/inline-definition" {
must 'not(public-key-format) or derived-from-or-self'
+ '(public-key-format, "ct:subject-public-key-'
+ 'info-format")';
}
refine "inline-or-keystore/central-keystore/"
+ "central-keystore-reference" {
must 'not(deref(.)/../ks:public-key-format) or '
+ 'derived-from-or-self(deref(.)/../ks:public-'
+ 'key-format, "ct:subject-public-key-info-format")';
}
}
}
grouping tls13-epsk {
description
"An External Pre-Shared Key (EPSK) is established
or provisioned out-of-band, i.e., not from a TLS
connection. An EPSK is a tuple of (Base Key,
External Identity, Hash). When PSKs are provisioned
out of band, the PSK identity and the Key Derivation
Function (KDF) hash algorithm to be used with the PSK
must also be provisioned.";
reference
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"RFC 8446: The Transport Layer Security (TLS) Protocol
Version 1.3, Section 4.2.11
RFC 9257: Guidance for External Pre-Shared Key (PSK) Usage
in TLS, Section 6
RFC 9258: Importing External Pre-Shared Keys (PSKs) for
TLS 1.3, Section 5.1";
uses ks:inline-or-keystore-symmetric-key-grouping;
leaf external-identity {
type string;
mandatory true;
description
"A sequence of bytes used to identify an EPSK. A label for
a pre-shared key established externally.";
reference
"RFC 8446: The Transport Layer Security (TLS) Protocol
Version 1.3, Section 4.2.11
RFC 9257: Guidance for External Pre-Shared Key (PSK)
Usage in TLS, Section 4.1";
}
leaf hash {
type tlscmn:epsk-supported-hash;
default "sha-256";
description
"For externally established PSKs, the Hash algorithm must be
set when the PSK is established or default to SHA-256 if no
such algorithm is defined.";
reference
"RFC 8446: The Transport Layer Security (TLS) Protocol
Version 1.3, Section 4.2.11";
}
leaf context {
type string;
description
"The context used to determine the EPSK, if any exists. For
example, context may include information about peer roles or
identities to mitigate Selfie-style reflection attacks.";
reference
"RFC 9258: Importing External Pre-Shared Keys (PSKs) for
TLS 1.3, Section 5.1 ";
}
leaf target-protocol {
type uint16;
description
"Specifies the protocol for which a PSK is imported for
use.";
reference
"RFC 9258: Importing External Pre-Shared Keys (PSKs) for
TLS 1.3, Section 3 ";
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}
leaf target-kdf {
type uint16;
description
"The KDF for which a PSK is imported for use.";
reference
"RFC 9258: Importing External Pre-Shared Keys (PSKs) for
TLS 1.3, Section 3";
}
}
grouping client-identity {
description
"Identity credentials that the TLS client may present when
establishing a connection to a TLS server. When configured,
and requested by the TLS server when establishing a TLS
session, these credentials are passed in the Certificate
message.";
reference
"RFC 8446: The Transport Layer Security (TLS) Protocol
Version 1.3, Section 4.4.2";
nacm:default-deny-write;
choice auth-type {
//default "certificate";
//mandatory true;
description
"A choice amongst authentication types, of which one must
be enabled and selected.";
case certificate {
container certificate {
description
"Specifies the client identity using a certificate.";
uses certificate;
}
}
case raw-public-key {
if-feature "tlsc:client-ident-raw-public-key";
container raw-private-key {
description
"Specifies the client identity using RPK.";
uses raw-private-key;
}
}
case tls13-epsk {
if-feature "tlsc:client-ident-tls13-epsk";
container tls13-epsk {
description
"An EPSK is established or provisioned out-of-band.";
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uses tls13-epsk;
}
}
}
}
grouping client-identity-with-ref {
description
"Identity credentials that the TLS client may present when
establishing a connection to a TLS server. When configured,
and requested by the TLS server when establishing a TLS
session, these credentials are passed in the Certificate
message.";
choice ref-or-explicit {
description
"A choice between a reference of explicit configuration.";
case ref {
description
"Provides a reference.";
leaf credentials-reference {
if-feature credential-reference;
type sys-tcs-plus:client-credentials-ref;
description
"Specifies the client credentials reference.";
}
}
case explicit {
description
"Explicit configuration.";
uses client-identity;
}
}
}
grouping server-authentication {
description
"Specifies how the TLS client can authenticate TLS servers.
Any combination of credentials is additive and unordered.";
nacm:default-deny-write;
container ca-certs {
presence
"Indicates that Certification Authority (CA) certificates
have been configured.
This statement is present so the mandatory descendant
nodes do not imply that this node must be configured.";
description
"A set of CA certificates used by the TLS client to
authenticate TLS server certificates.
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A server certificate is authenticated if it has a valid
chain of trust to a configured CA certificate.";
reference
"RFC 9641: A YANG Data Model for a Truststore";
uses ts:inline-or-truststore-certs-grouping;
}
container ee-certs {
presence
"Indicates that End Entity (EE) certificates have been
configured.
This statement is present so the mandatory descendant
nodes do not imply that this node must be configured.";
description
"A set of server certificates (i.e., end entity certificates)
used by the TLS client to authenticate certificates
presented by TLS servers. A server certificate is
authenticated if it is an exact match to a configured server
certificate.";
reference
"RFC 9641: A YANG Data Model for a Truststore";
uses ts:inline-or-truststore-certs-grouping;
}
container raw-public-keys {
if-feature "tlsc:server-auth-raw-public-key";
presence "Indicates that raw public keys have been configured.
This statement is present so the mandatory descendant
nodes do not imply that this node must be
configured.";
description
"A set of raw public keys used by the TLS client to
authenticate raw public keys presented by the TLS server.
A raw public key is authenticated if it is an exact match
to a configured raw public key.";
reference
"RFC 9641: A YANG Data Model for a Truststore";
uses ts:inline-or-truststore-public-keys-grouping {
refine "inline-or-truststore/inline/inline-definition/"
+ "public-key" {
must 'derived-from-or-self(public-key-format,'
+ ' "ct:subject-public-key-info-format")';
}
refine "inline-or-truststore/central-truststore/"
+ "central-truststore-reference" {
must 'not(deref(.)/../ts:public-key/ts:public-key-'
+ 'format[not(derived-from-or-self(., "ct:subject-'
+ 'public-key-info-format"))])';
}
}
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}
leaf tls13-epsks {
if-feature "tlsc:server-auth-tls13-epsk";
type empty;
description
"Indicates that the TLS client can authenticate TLS servers
using configured external PSKs.";
}
}
grouping server-authentication-with-ref {
description
"Specifies how the TLS client can authenticate TLS servers.";
choice ref-or-explicit {
description
"A choice between a reference of explicit configuration.";
case ref {
description
"Provides a reference.";
leaf credentials-reference {
if-feature credential-reference;
type sys-tcs-plus:server-credentials-ref;
description
"Specifies the server credentials reference.";
}
}
case explicit {
description
"Explicit configuration.";
uses server-authentication;
}
}
}
grouping hello-params {
description
"Configurable parameters for the TLS hello message.";
nacm:default-deny-write;
uses tlscmn:hello-params-grouping {
refine "tls-versions/min" {
must "not(derived-from-or-self(current(), "
+ "'tlscmn:tls12'))" {
error-message
"TLS 1.2 is not supported as min TLS version";
}
}
refine "tls-versions/max" {
must "not(derived-from-or-self(current(), "
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+ "'tlscmn:tls12'))" {
error-message
"TLS 1.2 is not supported as max TLS version";
}
}
}
}
grouping tls-client {
description
"A grouping for configuring a TLS client without any
consideration for how an underlying TCP session is
established.";
container client-identity {
presence
"Indicates that a TLS-level client identity has been
configured.
This statement is present so the mandatory descendant do
not imply that this node must be configured.";
description
"Identity credentials the TLS client may present when
establishing a connection to a TLS server.";
//uses client-identity;
uses client-identity-with-ref;
}
container server-authentication {
must 'ca-certs or ee-certs or raw-public-keys or tls13-epsks';
description
"Specifies how the TLS client can authenticate TLS servers.";
//uses server-authentication;
uses server-authentication-with-ref;
}
container hello-params {
if-feature "tlscmn:hello-params";
description
"Configurable parameters for the TLS hello message.";
uses hello-params;
}
}
grouping tls-grouping-reuse {
description
"A grouping for TLS with TLS1.2 and keepalive removed.";
uses tlsc:tls-client-grouping {
refine "client-identity/auth-type/tls12-psk" {
if-feature "not tlsc:client-ident-tls12-psk";
}
refine "server-authentication/tls12-psks" {
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if-feature "not tlsc:server-auth-tls12-psk";
}
refine "hello-params/tls-versions/min" {
must "not(derived-from-or-self(current(), "
+ "'tlscmn:tls12'))" {
error-message
"TLS 1.2 is not supported as min TLS version";
}
}
refine "hello-params/tls-versions/max" {
must "not(derived-from-or-self(current(), "
+ "'tlscmn:tls12'))" {
error-message
"TLS 1.2 is not supported as max TLS version";
}
}
refine "keepalives" {
if-feature "not tlsc:tls-client-keepalives";
}
}
}
grouping tacacs-plus {
description
"Grouping for TACACS+ attributes.";
container tacacs-plus {
must "not(derived-from-or-self(../sys:authentication"
+ "/sys:user-authentication-order, 'tacacs-plus'))"
+ " or bit-is-set(server/server-type,'authentication')" {
error-message
"When 'tacacs-plus' is used as a system authentication
method, a TACACS+ authentication server must be
configured.";
description
"When 'tacacs-plus' is used as an authentication method,
a TACACS+ server must be configured.";
}
description
"Container for TACACS+ configurations and operations.";
list client-credentials {
if-feature credential-reference;
key "id";
description
"Identity credentials the TLS client may present when
establishing a connection to a TLS server.
A list of client credentials to be referenced.";
nacm:default-deny-write;
leaf id {
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type string;
description
"A credential identifier.";
}
uses client-identity;
}
list server-credentials {
if-feature credential-reference;
key "id";
description
"Identity credentials the TLS client may present when
establishing a connection to a TLS server.";
nacm:default-deny-write;
leaf id {
type string;
description
"A credential identifier.";
}
uses server-authentication;
}
list server {
key "name";
ordered-by user;
description
"List of TACACS+ servers used by the device.";
leaf name {
type string;
description
"An arbitrary name for the TACACS+ server.";
}
leaf server-type {
type tacacs-plus-server-type;
mandatory true;
description
"Server type: authentication/authorization/accounting and
various combinations.";
}
leaf domain-name {
type inet:domain-name;
description
"Provides a domain name of the TACACS+ server.";
}
leaf address {
type inet:host;
mandatory true;
description
"The address of the TACACS+ server.";
}
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leaf port {
type inet:port-number;
default "49"; // to be replaced by TACACS-TLS-PORT
description
"The port number of TACACS+ Sserver port number.";
}
choice security {
mandatory true;
description
"Security mechanism between TACACS+ client and server.
This is modeled as a YANG 'choice' so that it can be
augmented by a YANG module in a backwards-compatible
manner.";
case tls {
description
"TLS is used.";
uses tls-client;
//uses client-identity-with-ref;
}
case obfuscation {
leaf shared-secret {
type string {
length "1..max";
}
description
"The shared secret, which is known to both the
TACACS+ client and server. TACACS+ server
administrators SHOULD configure a shared secret with
a minimum length of 16 characters.
It is highly recommended that this shared secret is
at least 32 characters long and sufficiently complex
with a mix of different character types,
i.e., upper case, lower case, numeric, and
punctuation. Note that this security mechanism is
best described as 'obfuscation' and not 'encryption'
as it does not provide any meaningful integrity,
privacy, or replay protection.";
reference
"RFC 8907: The TACACS+ Protocol";
nacm:default-deny-all;
}
}
}
choice source-type {
description
"The source address type for outbound TACACS+ packets.";
case source-ip {
leaf source-ip {
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type inet:ip-address;
description
"Specifies the source IP address for TACACS+ outbound
packets.";
}
}
case source-interface {
leaf source-interface {
type if:interface-ref;
description
"Specifies the interface from which the IP address
is derived for use as the source for the outbound
TACACS+ packet.";
}
}
}
leaf vrf-instance {
type leafref {
path "/ni:network-instances/ni:network-instance/ni:name";
}
description
"Specifies the VPN Routing and Forwarding (VRF) instance
to use to communicate with the TACACS+ server.";
reference
"RFC 8529: YANG Data Model for Network Instances";
}
leaf single-connection {
type boolean;
default "false";
description
"Indicates whether the Single Connection Mode is enabled
for the server. By default, the Single Connection Mode
is disabled.";
}
leaf timeout {
type uint16 {
range "1..max";
}
units "seconds";
default "5";
description
"The number of seconds the device will wait for a
response from each TACACS+ server before trying with a
different server.";
}
uses statistics;
}
}
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}
augment "/sys:system" {
description
"Augments the system model with the tacacs-plus model.";
uses tacacs-plus;
}
}
<CODE ENDS>
5. Security Considerations
This section is modeled after the template described in Section 3.7
of [I-D.ietf-netmod-rfc8407bis].
The "ietf-ac-common" YANG module defines a data model that is
designed to be accessed via YANG-based management protocols, such as
NETCONF [RFC6241] and RESTCONF [RFC8040]. These protocols have to
use a secure transport layer (e.g., SSH [RFC4252], TLS [RFC8446], and
QUIC [RFC9000]) and have to use mutual authentication.
The Network Configuration Access Control Model (NACM) [RFC8341]
provides the means to restrict access for particular NETCONF or
RESTCONF users to a preconfigured subset of all available NETCONF or
RESTCONF protocol operations and content.
There are a number of data nodes defined in this YANG module that are
writable/creatable/deletable (i.e., config true, which is the
default). These data nodes may be considered sensitive or vulnerable
in some network environments. Write operations (e.g., edit-config)
and delete operations to these data nodes without proper protection
or authentication can have a negative effect on network operations.
Specifically, the following subtrees and data nodes have particular
sensitivities/vulnerabilities:
/system/tacacs-plus/server: This list contains the data nodes used
to control the TACACS+ servers used by the device. Unauthorized
access to this list could enable an attacker to assume complete
control over the device by pointing to a compromised TACACS+
server, or to modify the counters to hide attacks against the
device.
/system/tacacs-plus/server/shared-secret: This leaf controls the key
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known to both the TACACS+ client and server. Unauthorized access
to this leaf could make the device vulnerable to attacks;
therefore, it has been restricted using the "default-deny-all"
access control defined in [RFC8341]. When setting, it is highly
recommended that the leaf is at least 32 characters long and
sufficiently complex with a mix of different character types,
i.e., upper case, lower case, numeric, and punctuation.
Some of the readable data nodes 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. Specifically, the following
subtrees and data nodes have particular sensitivities/
vulnerabilities:
'xxx':
: xxxx.
This YANG module uses groupings from other YANG modules that define
nodes that may be considered sensitive or vulnerable in network
environments. Refer to Section 5.3 of [RFC9645.] for information as
to which nodes may be considered sensitive or vulnerable in network
environments.
6. IANA Considerations
IANA is requested to update the following URI in the "ns" subregistry
within the "IETF XML Registry" [RFC3688]:
URI: urn:ietf:params:xml:ns:yang:ietf-system-tacacs-plus
Registrant Contact: The IESG.
XML: N/A; the requested URI is an XML namespace.
IANA is requested to register the following YANG module in the "YANG
Module Names" registry [RFC6020] within the "YANG Parameters"
registry group:
Name: ietf-system-tacacs-plus
Namespace: urn:ietf:params:xml:ns:yang:ietf-system-tacacs-plus
Prefix: sys-tcs-plus
Maintained by IANA? N
Reference: RFC XXXX
7. References
7.1. Normative References
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[I-D.ietf-opsawg-tacacs-tls13]
Dahm, T., Heasley, J., dcmgash@cisco.com, and A. Ota,
"Terminal Access Controller Access-Control System Plus
(TACACS+) over TLS 1.3", Work in Progress, Internet-Draft,
draft-ietf-opsawg-tacacs-tls13-15, 18 November 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-opsawg-
tacacs-tls13-15>.
[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/rfc/rfc2119>.
[RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
DOI 10.17487/RFC3688, January 2004,
<https://www.rfc-editor.org/rfc/rfc3688>.
[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/rfc/rfc6020>.
[RFC6520] Seggelmann, R., Tuexen, M., and M. Williams, "Transport
Layer Security (TLS) and Datagram Transport Layer Security
(DTLS) Heartbeat Extension", RFC 6520,
DOI 10.17487/RFC6520, February 2012,
<https://www.rfc-editor.org/rfc/rfc6520>.
[RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types",
RFC 6991, DOI 10.17487/RFC6991, July 2013,
<https://www.rfc-editor.org/rfc/rfc6991>.
[RFC7317] Bierman, A. and M. Bjorklund, "A YANG Data Model for
System Management", RFC 7317, DOI 10.17487/RFC7317, August
2014, <https://www.rfc-editor.org/rfc/rfc7317>.
[RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
RFC 7950, DOI 10.17487/RFC7950, August 2016,
<https://www.rfc-editor.org/rfc/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/rfc/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/rfc/rfc8341>.
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[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/rfc/rfc8342>.
[RFC8343] Bjorklund, M., "A YANG Data Model for Interface
Management", RFC 8343, DOI 10.17487/RFC8343, March 2018,
<https://www.rfc-editor.org/rfc/rfc8343>.
[RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol
Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
<https://www.rfc-editor.org/rfc/rfc8446>.
[RFC8529] Berger, L., Hopps, C., Lindem, A., Bogdanovic, D., and X.
Liu, "YANG Data Model for Network Instances", RFC 8529,
DOI 10.17487/RFC8529, March 2019,
<https://www.rfc-editor.org/rfc/rfc8529>.
[RFC9257] Housley, R., Hoyland, J., Sethi, M., and C. A. Wood,
"Guidance for External Pre-Shared Key (PSK) Usage in TLS",
RFC 9257, DOI 10.17487/RFC9257, July 2022,
<https://www.rfc-editor.org/rfc/rfc9257>.
[RFC9258] Benjamin, D. and C. A. Wood, "Importing External Pre-
Shared Keys (PSKs) for TLS 1.3", RFC 9258,
DOI 10.17487/RFC9258, July 2022,
<https://www.rfc-editor.org/rfc/rfc9258>.
[RFC9640] Watsen, K., "YANG Data Types and Groupings for
Cryptography", RFC 9640, DOI 10.17487/RFC9640, October
2024, <https://www.rfc-editor.org/rfc/rfc9640>.
[RFC9641] Watsen, K., "A YANG Data Model for a Truststore",
RFC 9641, DOI 10.17487/RFC9641, October 2024,
<https://www.rfc-editor.org/rfc/rfc9641>.
[RFC9642] Watsen, K., "A YANG Data Model for a Keystore", RFC 9642,
DOI 10.17487/RFC9642, October 2024,
<https://www.rfc-editor.org/rfc/rfc9642>.
[RFC9645] Watsen, K., "YANG Groupings for TLS Clients and TLS
Servers", RFC 9645, DOI 10.17487/RFC9645, October 2024,
<https://www.rfc-editor.org/rfc/rfc9645>.
[RFC9645.] Watsen, K., "YANG Groupings for TLS Clients and TLS
Servers", RFC 9645, DOI 10.17487/RFC9645, October 2024,
<https://www.rfc-editor.org/rfc/rfc9645>.
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7.2. Informative References
[I-D.ietf-netmod-rfc8407bis]
Bierman, A., Boucadair, M., and Q. Wu, "Guidelines for
Authors and Reviewers of Documents Containing YANG Data
Models", Work in Progress, Internet-Draft, draft-ietf-
netmod-rfc8407bis-21, 13 November 2024,
<https://datatracker.ietf.org/doc/html/draft-ietf-netmod-
rfc8407bis-21>.
[RFC4252] Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH)
Authentication Protocol", RFC 4252, DOI 10.17487/RFC4252,
January 2006, <https://www.rfc-editor.org/rfc/rfc4252>.
[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/rfc/rfc6241>.
[RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
<https://www.rfc-editor.org/rfc/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/rfc/rfc8340>.
[RFC8907] Dahm, T., Ota, A., Medway Gash, D.C., Carrel, D., and L.
Grant, "The Terminal Access Controller Access-Control
System Plus (TACACS+) Protocol", RFC 8907,
DOI 10.17487/RFC8907, September 2020,
<https://www.rfc-editor.org/rfc/rfc8907>.
[RFC9000] Iyengar, J., Ed. and M. Thomson, Ed., "QUIC: A UDP-Based
Multiplexed and Secure Transport", RFC 9000,
DOI 10.17487/RFC9000, May 2021,
<https://www.rfc-editor.org/rfc/rfc9000>.
[RFC9105] Wu, B., Ed., Zheng, G., and M. Wang, Ed., "A YANG Data
Model for Terminal Access Controller Access-Control System
Plus (TACACS+)", RFC 9105, DOI 10.17487/RFC9105, August
2021, <https://www.rfc-editor.org/rfc/rfc9105>.
Appendix A. Full Tree
The full tree structure is shown below:
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=============== NOTE: '\' line wrapping per RFC 8792 ================
module: ietf-system-tacacs-plus
augment /sys:system:
+--rw tacacs-plus
+--rw client-credentials* [id] {credential-reference}?
| +--rw id string
| +--rw (auth-type)?
| +--:(certificate)
| | +--rw certificate
| | +--rw (inline-or-keystore)
| | +--:(inline) {inline-definitions-supported}?
| | | +--rw inline-definition
| | | +--rw public-key-format?
| | | | identityref
| | | +--rw public-key?
| | | | binary
| | | +--rw private-key-format?
| | | | identityref
| | | +--rw (private-key-type)
| | | | +--:(cleartext-private-key)
| | | | | {cleartext-private-keys}?
| | | | | +--rw cleartext-private-key?
| | | | | binary
| | | | +--:(hidden-private-key)
| | | | | {hidden-private-keys}?
| | | | | +--rw hidden-private-key?
| | | | | empty
| | | | +--:(encrypted-private-key)
| | | | {encrypted-private-keys}?
| | | | +--rw encrypted-private-key
| | | | +--rw encrypted-by
| | | | +--rw encrypted-value-format
| | | | | identityref
| | | | +--rw encrypted-value
| | | | binary
| | | +--rw cert-data?
| | | | end-entity-cert-cms
| | | +---n certificate-expiration
| | | | {certificate-expiration-\
notification}?
| | | | +-- expiration-date
| | | | yang:date-and-time
| | | +---x generate-csr {csr-generation}?
| | | +---w input
| | | | +---w csr-format identityref
| | | | +---w csr-info csr-info
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| | | +--ro output
| | | +--ro (csr-type)
| | | +--:(p10-csr)
| | | +--ro p10-csr? p10-csr
| | +--:(central-keystore)
| | {central-keystore-supported,\
asymmetric-keys}?
| | +--rw central-keystore-reference
| | +--rw asymmetric-key?
| | | ks:central-asymmetric-key-ref
| | | {central-keystore-supported,\
asymmetric-keys}?
| | +--rw certificate? leafref
| +--:(raw-public-key) {tlsc:client-ident-raw-public-key}?
| | +--rw raw-private-key
| | +--rw (inline-or-keystore)
| | +--:(inline) {inline-definitions-supported}?
| | | +--rw inline-definition
| | | +--rw public-key-format?
| | | | identityref
| | | +--rw public-key?
| | | | binary
| | | +--rw private-key-format?
| | | | identityref
| | | +--rw (private-key-type)
| | | +--:(cleartext-private-key)
| | | | {cleartext-private-keys}?
| | | | +--rw cleartext-private-key?
| | | | binary
| | | +--:(hidden-private-key)
| | | | {hidden-private-keys}?
| | | | +--rw hidden-private-key?
| | | | empty
| | | +--:(encrypted-private-key)
| | | {encrypted-private-keys}?
| | | +--rw encrypted-private-key
| | | +--rw encrypted-by
| | | +--rw encrypted-value-format
| | | | identityref
| | | +--rw encrypted-value
| | | binary
| | +--:(central-keystore)
| | {central-keystore-supported,\
asymmetric-keys}?
| | +--rw central-keystore-reference?
| | ks:central-asymmetric-key-ref
| +--:(tls13-epsk) {tlsc:client-ident-tls13-epsk}?
| +--rw tls13-epsk
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| +--rw (inline-or-keystore)
| | +--:(inline) {inline-definitions-supported}?
| | | +--rw inline-definition
| | | +--rw key-format?
| | | | identityref
| | | +--rw (key-type)
| | | +--:(cleartext-symmetric-key)
| | | | +--rw cleartext-symmetric-key?
| | | | binary
| | | | {cleartext-symmetric-keys}?
| | | +--:(hidden-symmetric-key)
| | | | {hidden-symmetric-keys}?
| | | | +--rw hidden-symmetric-key?
| | | | empty
| | | +--:(encrypted-symmetric-key)
| | | {encrypted-symmetric-keys}?
| | | +--rw encrypted-symmetric-key
| | | +--rw encrypted-by
| | | +--rw encrypted-value-format
| | | | identityref
| | | +--rw encrypted-value
| | | binary
| | +--:(central-keystore)
| | {central-keystore-supported,symmetric\
-keys}?
| | +--rw central-keystore-reference?
| | ks:central-symmetric-key-ref
| +--rw external-identity string
| +--rw hash?
| | tlscmn:epsk-supported-hash
| +--rw context? string
| +--rw target-protocol? uint16
| +--rw target-kdf? uint16
+--rw server-credentials* [id] {credential-reference}?
| +--rw id string
| +--rw ca-certs!
| | +--rw (inline-or-truststore)
| | +--:(inline) {inline-definitions-supported}?
| | | +--rw inline-definition
| | | +--rw certificate* [name]
| | | +--rw name string
| | | +--rw cert-data
| | | | trust-anchor-cert-cms
| | | +---n certificate-expiration
| | | {certificate-expiration-\
notification}?
| | | +-- expiration-date yang:date-and-time
| | +--:(central-truststore)
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| | {central-truststore-supported,certificates}?
| | +--rw central-truststore-reference?
| | ts:central-certificate-bag-ref
| +--rw ee-certs!
| | +--rw (inline-or-truststore)
| | +--:(inline) {inline-definitions-supported}?
| | | +--rw inline-definition
| | | +--rw certificate* [name]
| | | +--rw name string
| | | +--rw cert-data
| | | | trust-anchor-cert-cms
| | | +---n certificate-expiration
| | | {certificate-expiration-\
notification}?
| | | +-- expiration-date yang:date-and-time
| | +--:(central-truststore)
| | {central-truststore-supported,certificates}?
| | +--rw central-truststore-reference?
| | ts:central-certificate-bag-ref
| +--rw raw-public-keys! {tlsc:server-auth-raw-public-key}?
| | +--rw (inline-or-truststore)
| | +--:(inline) {inline-definitions-supported}?
| | | +--rw inline-definition
| | | +--rw public-key* [name]
| | | +--rw name string
| | | +--rw public-key-format identityref
| | | +--rw public-key binary
| | +--:(central-truststore)
| | {central-truststore-supported,public-keys}?
| | +--rw central-truststore-reference?
| | ts:central-public-key-bag-ref
| +--rw tls13-epsks? empty
| {tlsc:server-auth-tls13-epsk}?
+--rw server* [name]
+--rw name string
+--rw server-type
| tacacs-plus-server-type
+--rw domain-name? inet:domain-name
+--rw address inet:host
+--rw port? inet:port-number
+--rw (security)
| +--:(tls)
| | +--rw client-identity!
| | | +--rw (ref-or-explicit)?
| | | +--:(ref)
| | | | +--rw credentials-reference?
| | | | sys-tcs-plus:client-credentials-ref
| | | | {credential-reference}?
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| | | +--:(explicit)
| | | +--rw (auth-type)?
| | | +--:(certificate)
| | | | +--rw certificate
| | | | +--rw (inline-or-keystore)
| | | | +--:(inline)
| | | | | {inline-definitions-\
supported}?
| | | | | +--rw inline-definition
| | | | | +--rw public-key-format?
| | | | | | identityref
| | | | | +--rw public-key?
| | | | | | binary
| | | | | +--rw private-key-format?
| | | | | | identityref
| | | | | +--rw (private-key-type)
| | | | | | +--:(cleartext-private\
-key)
| | | | | | | {cleartext-\
private-keys}?
| | | | | | | +--rw cleartext-\
private-key?
| | | | | | | binary
| | | | | | +--:(hidden-private-\
key)
| | | | | | | {hidden-\
private-keys}?
| | | | | | | +--rw hidden-\
private-key?
| | | | | | | empty
| | | | | | +--:(encrypted-private\
-key)
| | | | | | {encrypted-\
private-keys}?
| | | | | | +--rw encrypted-\
private-key
| | | | | | +--rw encrypted-\
by
| | | | | | +--rw encrypted-\
value-format
| | | | | | | \
identityref
| | | | | | +--rw encrypted-\
value
| | | | | | binary
| | | | | +--rw cert-data?
| | | | | | end-entity-cert-\
cms
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| | | | | +---n certificate-\
expiration
| | | | | | {certificate-\
expiration-notification}?
| | | | | | +-- expiration-date
| | | | | | yang:date-and-\
time
| | | | | +---x generate-csr
| | | | | {csr-generation}?
| | | | | +---w input
| | | | | | +---w csr-format
| | | | | | | identityref
| | | | | | +---w csr-info
| | | | | | csr-info
| | | | | +--ro output
| | | | | +--ro (csr-type)
| | | | | +--:(p10-csr)
| | | | | +--ro p10-csr?
| | | | | p10-\
csr
| | | | +--:(central-keystore)
| | | | {central-keystore-\
supported,asymmetric-keys}?
| | | | +--rw central-keystore-\
reference
| | | | +--rw asymmetric-key?
| | | | | ks:central-\
asymmetric-key-ref
| | | | | {central-keystore\
-supported,asymmetric-keys}?
| | | | +--rw certificate?
| | | | leafref
| | | +--:(raw-public-key)
| | | | {tlsc:client-ident-raw-public-\
key}?
| | | | +--rw raw-private-key
| | | | +--rw (inline-or-keystore)
| | | | +--:(inline)
| | | | | {inline-definitions-\
supported}?
| | | | | +--rw inline-definition
| | | | | +--rw public-key-format?
| | | | | | identityref
| | | | | +--rw public-key?
| | | | | | binary
| | | | | +--rw private-key-format?
| | | | | | identityref
| | | | | +--rw (private-key-type)
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| | | | | +--:(cleartext-private\
-key)
| | | | | | {cleartext-\
private-keys}?
| | | | | | +--rw cleartext-\
private-key?
| | | | | | binary
| | | | | +--:(hidden-private-\
key)
| | | | | | {hidden-\
private-keys}?
| | | | | | +--rw hidden-\
private-key?
| | | | | | empty
| | | | | +--:(encrypted-private\
-key)
| | | | | {encrypted-\
private-keys}?
| | | | | +--rw encrypted-\
private-key
| | | | | +--rw encrypted-\
by
| | | | | +--rw encrypted-\
value-format
| | | | | | \
identityref
| | | | | +--rw encrypted-\
value
| | | | | binary
| | | | +--:(central-keystore)
| | | | {central-keystore-\
supported,asymmetric-keys}?
| | | | +--rw central-keystore-\
reference?
| | | | ks:central-\
asymmetric-key-ref
| | | +--:(tls13-epsk)
| | | {tlsc:client-ident-tls13-epsk}?
| | | +--rw tls13-epsk
| | | +--rw (inline-or-keystore)
| | | | +--:(inline)
| | | | | {inline-definitions-\
supported}?
| | | | | +--rw inline-definition
| | | | | +--rw key-format?
| | | | | | identityref
| | | | | +--rw (key-type)
| | | | | +--:(cleartext-\
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symmetric-key)
| | | | | | +--rw cleartext-\
symmetric-key?
| | | | | | binary
| | | | | | {cleartext-\
symmetric-keys}?
| | | | | +--:(hidden-symmetric-\
key)
| | | | | | {hidden-\
symmetric-keys}?
| | | | | | +--rw hidden-\
symmetric-key?
| | | | | | empty
| | | | | +--:(encrypted-\
symmetric-key)
| | | | | {encrypted-\
symmetric-keys}?
| | | | | +--rw encrypted-\
symmetric-key
| | | | | +--rw encrypted-\
by
| | | | | +--rw encrypted-\
value-format
| | | | | | \
identityref
| | | | | +--rw encrypted-\
value
| | | | | binary
| | | | +--:(central-keystore)
| | | | {central-keystore-\
supported,symmetric-keys}?
| | | | +--rw central-keystore-\
reference?
| | | | ks:central-symmetric\
-key-ref
| | | +--rw external-identity
| | | | string
| | | +--rw hash?
| | | | tlscmn:epsk-supported-hash
| | | +--rw context?
| | | | string
| | | +--rw target-protocol?
| | | | uint16
| | | +--rw target-kdf?
| | | uint16
| | +--rw server-authentication
| | | +--rw (ref-or-explicit)?
| | | +--:(ref)
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| | | | +--rw credentials-reference?
| | | | sys-tcs-plus:server-credentials-ref
| | | | {credential-reference}?
| | | +--:(explicit)
| | | +--rw ca-certs!
| | | | +--rw (inline-or-truststore)
| | | | +--:(inline)
| | | | | {inline-definitions-\
supported}?
| | | | | +--rw inline-definition
| | | | | +--rw certificate* [name]
| | | | | +--rw name
| | | | | | string
| | | | | +--rw cert-data
| | | | | | trust-anchor-cert-cms
| | | | | +---n certificate-expiration
| | | | | {certificate-\
expiration-notification}?
| | | | | +-- expiration-date
| | | | | yang:date-and-time
| | | | +--:(central-truststore)
| | | | {central-truststore-\
supported,certificates}?
| | | | +--rw central-truststore-reference?
| | | | ts:central-certificate-bag\
-ref
| | | +--rw ee-certs!
| | | | +--rw (inline-or-truststore)
| | | | +--:(inline)
| | | | | {inline-definitions-\
supported}?
| | | | | +--rw inline-definition
| | | | | +--rw certificate* [name]
| | | | | +--rw name
| | | | | | string
| | | | | +--rw cert-data
| | | | | | trust-anchor-cert-cms
| | | | | +---n certificate-expiration
| | | | | {certificate-\
expiration-notification}?
| | | | | +-- expiration-date
| | | | | yang:date-and-time
| | | | +--:(central-truststore)
| | | | {central-truststore-\
supported,certificates}?
| | | | +--rw central-truststore-reference?
| | | | ts:central-certificate-bag\
-ref
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| | | +--rw raw-public-keys!
| | | | {tlsc:server-auth-raw-public-key}?
| | | | +--rw (inline-or-truststore)
| | | | +--:(inline)
| | | | | {inline-definitions-\
supported}?
| | | | | +--rw inline-definition
| | | | | +--rw public-key* [name]
| | | | | +--rw name
| | | | | | string
| | | | | +--rw public-key-format
| | | | | | identityref
| | | | | +--rw public-key
| | | | | binary
| | | | +--:(central-truststore)
| | | | {central-truststore-\
supported,public-keys}?
| | | | +--rw central-truststore-reference?
| | | | ts:central-public-key-bag-\
ref
| | | +--rw tls13-epsks? empty
| | | {tlsc:server-auth-tls13-epsk}?
| | +--rw hello-params {tlscmn:hello-params}?
| | +--rw tls-versions
| | | +--rw min? identityref
| | | +--rw max? identityref
| | +--rw cipher-suites
| | +--rw cipher-suite*
| | tlscsa:tls-cipher-suite-algorithm
| +--:(obfuscation)
| +--rw shared-secret? string
+--rw (source-type)?
| +--:(source-ip)
| | +--rw source-ip? inet:ip-address
| +--:(source-interface)
| +--rw source-interface? if:interface-ref
+--rw vrf-instance?
| -> /ni:network-instances/network-instance/name
+--rw single-connection? boolean
+--rw timeout? uint16
+--ro statistics
+--ro connection-opens? yang:counter64
+--ro connection-closes? yang:counter64
+--ro connection-aborts? yang:counter64
+--ro connection-failures? yang:counter64
+--ro connection-timeouts? yang:counter64
+--ro messages-sent? yang:counter64
+--ro messages-received? yang:counter64
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+--ro errors-received? yang:counter64
+--ro sessions? yang:counter64
Acknowledgments
The document leverages data structures defined in [RFC9645].
Thanks toJoe Clarke and Tom Petch for the review and comments.
Authors' Addresses
Mohamed Boucadair (editor)
Orange
Email: mohamed.boucadair@orange.com
Bo Wu
Huawei Technologies
Email: mlana.wubo@huawei.com
Guangying Zheng
Huawei Technologies
Email: zhengguangying@huawei.com
Michael Wang
Huawei Technologies
Email: wangzitao@huawei.com
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