YANG Groupings for SSH Clients and SSH Servers
draft-ietf-netconf-ssh-client-server-25

Document Type Active Internet-Draft (netconf WG)
Author Kent Watsen 
Last updated 2021-06-18
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NETCONF Working Group                                          K. Watsen
Internet-Draft                                           Watsen Networks
Intended status: Standards Track                            18 June 2021
Expires: 20 December 2021

             YANG Groupings for SSH Clients and SSH Servers
                draft-ietf-netconf-ssh-client-server-25

Abstract

   This document defines three YANG 1.1 modules: the first defines
   features and groupings common to both SSH clients and SSH servers,
   the second defines a grouping for a generic SSH client, and the third
   defines a grouping for a generic SSH server.

Editorial Note (To be removed by RFC Editor)

   This draft contains placeholder values that need to be replaced with
   finalized values at the time of publication.  This note summarizes
   all of the substitutions that are needed.  No other RFC Editor
   instructions are specified elsewhere in this document.

   Artwork in this document contains shorthand references to drafts in
   progress.  Please apply the following replacements:

   *  "AAAA" --> the assigned RFC value for draft-ietf-netconf-crypto-
      types

   *  "BBBB" --> the assigned RFC value for draft-ietf-netconf-trust-
      anchors

   *  "CCCC" --> the assigned RFC value for draft-ietf-netconf-keystore

   *  "DDDD" --> the assigned RFC value for draft-ietf-netconf-tcp-
      client-server

   *  "EEEE" --> 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:

   *  "2021-06-18" --> the publication date of this draft

   The following Appendix section is to be removed prior to publication:

   *  Appendix B.  Change Log

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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 20 December 2021.

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  . . . . . . . . . . . . . . . . . . . . . . . .   4
     1.1.  Relation to other RFCs  . . . . . . . . . . . . . . . . .   5
     1.2.  Specification Language  . . . . . . . . . . . . . . . . .   6
     1.3.  Adherence to the NMDA . . . . . . . . . . . . . . . . . .   6
   2.  The "ietf-ssh-common" Module  . . . . . . . . . . . . . . . .   6
     2.1.  Data Model Overview . . . . . . . . . . . . . . . . . . .   7
     2.2.  Example Usage . . . . . . . . . . . . . . . . . . . . . .   8
     2.3.  YANG Module . . . . . . . . . . . . . . . . . . . . . . .   9
   3.  The "ietf-ssh-client" Module  . . . . . . . . . . . . . . . .  13
     3.1.  Data Model Overview . . . . . . . . . . . . . . . . . . .  13
     3.2.  Example Usage . . . . . . . . . . . . . . . . . . . . . .  16
     3.3.  YANG Module . . . . . . . . . . . . . . . . . . . . . . .  20
   4.  The "ietf-ssh-server" Module  . . . . . . . . . . . . . . . .  27
     4.1.  Data Model Overview . . . . . . . . . . . . . . . . . . .  27
     4.2.  Example Usage . . . . . . . . . . . . . . . . . . . . . .  30

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     4.3.  YANG Module . . . . . . . . . . . . . . . . . . . . . . .  34
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  43
     5.1.  The "iana-ssh-key-exchange-algs" Module . . . . . . . . .  43
     5.2.  The "iana-ssh-encryption-algs" Module . . . . . . . . . .  43
     5.3.  The "iana-ssh-mac-algs" Module  . . . . . . . . . . . . .  44
     5.4.  The "iana-ssh-public-key-algs" Module . . . . . . . . . .  44
     5.5.  The "ietf-ssh-common" YANG Module . . . . . . . . . . . .  45
     5.6.  The "ietf-ssh-client" YANG Module . . . . . . . . . . . .  46
     5.7.  The "ietf-ssh-server" YANG Module . . . . . . . . . . . .  47
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  47
     6.1.  The "IETF XML" Registry . . . . . . . . . . . . . . . . .  47
     6.2.  The "YANG Module Names" Registry  . . . . . . . . . . . .  48
     6.3.  The "iana-ssh-encryption-algs" Module . . . . . . . . . .  49
     6.4.  The "iana-ssh-mac-algs" Module  . . . . . . . . . . . . .  50
     6.5.  The "iana-ssh-public-key-algs" Module . . . . . . . . . .  50
     6.6.  The "iana-ssh-key-exchange-algs" Module . . . . . . . . .  51
   7.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  51
     7.1.  Normative References  . . . . . . . . . . . . . . . . . .  51
     7.2.  Informative References  . . . . . . . . . . . . . . . . .  53
   Appendix A.  YANG Modules for IANA  . . . . . . . . . . . . . . .  55
     A.1.  Initial Module for the "Encryption Algorithm Names"
           Registry  . . . . . . . . . . . . . . . . . . . . . . . .  55
       A.1.1.  Data Model Overview . . . . . . . . . . . . . . . . .  56
       A.1.2.  Example Usage . . . . . . . . . . . . . . . . . . . .  56
       A.1.3.  YANG Module . . . . . . . . . . . . . . . . . . . . .  57
     A.2.  Initial Module for the "MAC Algorithm Names" Registry . .  65
       A.2.1.  Data Model Overview . . . . . . . . . . . . . . . . .  65
       A.2.2.  Example Usage . . . . . . . . . . . . . . . . . . . .  66
       A.2.3.  YANG Module . . . . . . . . . . . . . . . . . . . . .  66
     A.3.  Initial Module for the "Public Key Algorithm Names"
           Registry  . . . . . . . . . . . . . . . . . . . . . . . .  69
       A.3.1.  Data Model Overview . . . . . . . . . . . . . . . . .  69
       A.3.2.  Example Usage . . . . . . . . . . . . . . . . . . . .  70
       A.3.3.  YANG Module . . . . . . . . . . . . . . . . . . . . .  71
     A.4.  Initial Module for the "Key Exchange Method Names"
           Registry  . . . . . . . . . . . . . . . . . . . . . . . .  80
       A.4.1.  Data Model Overview . . . . . . . . . . . . . . . . .  80
       A.4.2.  Example Usage . . . . . . . . . . . . . . . . . . . .  80
       A.4.3.  YANG Module . . . . . . . . . . . . . . . . . . . . .  81
   Appendix B.  Change Log . . . . . . . . . . . . . . . . . . . . . 127
     B.1.  00 to 01  . . . . . . . . . . . . . . . . . . . . . . . . 127
     B.2.  01 to 02  . . . . . . . . . . . . . . . . . . . . . . . . 127
     B.3.  02 to 03  . . . . . . . . . . . . . . . . . . . . . . . . 128
     B.4.  03 to 04  . . . . . . . . . . . . . . . . . . . . . . . . 128
     B.5.  04 to 05  . . . . . . . . . . . . . . . . . . . . . . . . 128
     B.6.  05 to 06  . . . . . . . . . . . . . . . . . . . . . . . . 128
     B.7.  06 to 07  . . . . . . . . . . . . . . . . . . . . . . . . 129
     B.8.  07 to 08  . . . . . . . . . . . . . . . . . . . . . . . . 129

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     B.9.  08 to 09  . . . . . . . . . . . . . . . . . . . . . . . . 129
     B.10. 09 to 10  . . . . . . . . . . . . . . . . . . . . . . . . 129
     B.11. 10 to 11  . . . . . . . . . . . . . . . . . . . . . . . . 129
     B.12. 11 to 12  . . . . . . . . . . . . . . . . . . . . . . . . 129
     B.13. 12 to 13  . . . . . . . . . . . . . . . . . . . . . . . . 130
     B.14. 13 to 14  . . . . . . . . . . . . . . . . . . . . . . . . 130
     B.15. 14 to 15  . . . . . . . . . . . . . . . . . . . . . . . . 130
     B.16. 15 to 16  . . . . . . . . . . . . . . . . . . . . . . . . 130
     B.17. 16 to 17  . . . . . . . . . . . . . . . . . . . . . . . . 131
     B.18. 17 to 18  . . . . . . . . . . . . . . . . . . . . . . . . 131
     B.19. 18 to 19  . . . . . . . . . . . . . . . . . . . . . . . . 131
     B.20. 19 to 20  . . . . . . . . . . . . . . . . . . . . . . . . 132
     B.21. 20 to 21  . . . . . . . . . . . . . . . . . . . . . . . . 132
     B.22. 21 to 22  . . . . . . . . . . . . . . . . . . . . . . . . 132
     B.23. 22 to 23  . . . . . . . . . . . . . . . . . . . . . . . . 132
     B.24. 23 to 24  . . . . . . . . . . . . . . . . . . . . . . . . 133
     B.25. 24 to 25  . . . . . . . . . . . . . . . . . . . . . . . . 133
   Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . . 133
   Contributors  . . . . . . . . . . . . . . . . . . . . . . . . . . 133
   Author's Address  . . . . . . . . . . . . . . . . . . . . . . . . 134

1.  Introduction

   This document defines three YANG 1.1 [RFC7950] modules: the first
   defines features and groupings common to both SSH clients and SSH
   servers, the second defines a grouping for a generic SSH client, and
   the third defines a grouping for a generic SSH server.  It is
   intended that these groupings will be used by applications using the
   SSH protocol [RFC4252], [RFC4253], and [RFC4254].  For instance,
   these groupings could be used to help define the data model for an
   OpenSSH [OPENSSH] server or a NETCONF over SSH [RFC6242] based
   server.

   The client and server YANG modules in this document each define one
   grouping, which is focused on just SSH-specific configuration, and
   specifically avoids any transport-level configuration, such as what
   ports to listen on or connect to.  This affords applications the
   opportunity to define their own strategy for how the underlying TCP
   connection is established.  For instance, applications supporting
   NETCONF Call Home [RFC8071] could use the "ssh-server-grouping"
   grouping for the SSH parts it provides, while adding data nodes for
   the TCP-level call-home configuration.

   The modules defined in this document use groupings defined in
   [I-D.ietf-netconf-keystore] enabling keys to be either locally
   defined or a reference to globally configured values.

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   The modules defined in this document optionally support [RFC6187]
   enabling X.509v3 certificate based host keys and public keys.

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.

                                  crypto-types
                                    ^      ^
                                   /        \
                                  /          \
                         truststore         keystore
                          ^     ^             ^  ^
                          |     +---------+   |  |
                          |               |   |  |
                          |      +------------+  |
   tcp-client-server      |     /         |      |
      ^    ^        ssh-client-server     |      |
      |    |           ^            tls-client-server
      |    |           |              ^     ^        http-client-server
      |    |           |              |     |                 ^
      |    |           |        +-----+     +---------+       |
      |    |           |        |                     |       |
      |    +-----------|--------|--------------+      |       |
      |                |        |              |      |       |
      +-----------+    |        |              |      |       |
                  |    |        |              |      |       |
                  |    |        |              |      |       |
               netconf-client-server       restconf-client-server

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   +=======================+===========================================+
   |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

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].  For instance, as described in
   [I-D.ietf-netconf-trust-anchors] and [I-D.ietf-netconf-keystore],
   trust anchors and keys installed during manufacturing are expected to
   appear in <operational>.

2.  The "ietf-ssh-common" Module

   The SSH common model presented in this section contains features and
   groupings common to both SSH clients and SSH servers.  The
   "transport-params-grouping" grouping can be used to configure the
   list of SSH transport algorithms permitted by the SSH client or SSH
   server.  The lists of algorithms are ordered such that, if multiple
   algorithms are permitted by the client, the algorithm that appears

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   first in its list that is also permitted by the server is used for
   the SSH transport layer connection.  The ability to restrict the
   algorithms allowed is provided in this grouping for SSH clients and
   SSH servers that are capable of doing so and may serve to make SSH
   clients and SSH servers compliant with security policies.

2.1.  Data Model Overview

   This section provides an overview of the "ietf-ssh-common" module in
   terms of its features, identities, and groupings.

2.1.1.  Features

   The following diagram lists all the "feature" statements defined in
   the "ietf-ssh-common" module:

   Features:
     +-- ssh-x509-certs
     +-- transport-params

      |  The diagram above uses syntax that is similar to but not
      |  defined in [RFC8340].

2.1.2.  Groupings

   The "ietf-ssh-common" module defines the following "grouping"
   statement:

   *  transport-params-grouping

   This grouping is presented in the following subsection.

2.1.2.1.  The "transport-params-grouping" Grouping

   The following tree diagram [RFC8340] illustrates the "transport-
   params-grouping" grouping:

     grouping transport-params-grouping
       +-- host-key
       |  +-- host-key-alg*   identityref
       +-- key-exchange
       |  +-- key-exchange-alg*   identityref
       +-- encryption
       |  +-- encryption-alg*   identityref
       +-- mac
          +-- mac-alg*   identityref

   Comments:

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   *  This grouping is used by both the "ssh-client-grouping" and the
      "ssh-server-grouping" groupings defined in Section 3.1.2.1 and
      Section 4.1.2.1, respectively.

   *  This grouping enables client and server configurations to specify
      the algorithms that are to be used when establishing SSH sessions.

   *  Each list is "ordered-by user".

2.1.3.  Protocol-accessible Nodes

   The "ietf-ssh-common" module defines only "grouping" statements that
   are used by other modules to instantiate protocol-accessible nodes.

2.2.  Example Usage

   This following example illustrates how the "transport-params-
   grouping' grouping appears when populated with some data.

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   =============== NOTE: '\' line wrapping per RFC 8792 ================

   <!-- The outermost element below doesn't exist in the data model. -->
   <!--  It simulates if the "grouping" were a "container" instead.  -->

   <transport-params
     xmlns="urn:ietf:params:xml:ns:yang:ietf-ssh-common"
     xmlns:sshea="urn:ietf:params:xml:ns:yang:iana-ssh-encryption-algs"
     xmlns:sshkea="urn:ietf:params:xml:ns:yang:iana-ssh-key-exchange-al\
   gs"
     xmlns:sshma="urn:ietf:params:xml:ns:yang:iana-ssh-mac-algs"
     xmlns:sshpka="urn:ietf:params:xml:ns:yang:iana-ssh-public-key-algs\
   ">
     <host-key>
       <host-key-alg>sshpka:x509v3-rsa2048-sha256</host-key-alg>
       <host-key-alg>sshpka:ssh-rsa</host-key-alg>
     </host-key>
     <key-exchange>
       <key-exchange-alg>
         sshkea:diffie-hellman-group-exchange-sha256
       </key-exchange-alg>
     </key-exchange>
     <encryption>
       <encryption-alg>sshea:aes256-ctr</encryption-alg>
       <encryption-alg>sshea:aes192-ctr</encryption-alg>
       <encryption-alg>sshea:aes128-ctr</encryption-alg>
       <encryption-alg>sshea:aes256-cbc</encryption-alg>
       <encryption-alg>sshea:aes192-cbc</encryption-alg>
       <encryption-alg>sshea:aes128-cbc</encryption-alg>
     </encryption>
     <mac>
       <mac-alg>sshma:hmac-sha2-256</mac-alg>
       <mac-alg>sshma:hmac-sha2-512</mac-alg>
     </mac>
   </transport-params>

2.3.  YANG Module

   This YANG module has normative references to [RFC4253], [RFC4344],
   [RFC4419], [RFC5656], [RFC6187], and [RFC6668].

   <CODE BEGINS> file "ietf-ssh-common@2021-06-18.yang"

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   module ietf-ssh-common {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-ssh-common";
     prefix sshcmn;

     import iana-ssh-encryption-algs {
       prefix sshea;
       reference
         "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
     }

     import iana-ssh-key-exchange-algs {
       prefix sshkea;
       reference
         "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
     }

     import iana-ssh-mac-algs {
       prefix sshma;
       reference
         "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
     }

     import iana-ssh-public-key-algs {
       prefix sshpka;
       reference
         "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
     }

     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>
        Author:   Gary Wu <mailto:garywu@cisco.com>";

     description
       "This module defines a common features and groupings for
        Secure Shell (SSH).

        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

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        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 EEEE
        (https://www.rfc-editor.org/info/rfcEEEE); 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 2021-06-18 {
       description
         "Initial version";
       reference
         "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
     }

     // Features

     feature ssh-x509-certs {
       description
         "X.509v3 certificates are supported for SSH.";
       reference
         "RFC 6187: X.509v3 Certificates for Secure Shell
                    Authentication";
     }

     feature transport-params {
       description
         "SSH transport layer parameters are configurable.";
     }

     // Groupings

     grouping transport-params-grouping {
       description
         "A reusable grouping for SSH transport parameters.";
       reference
         "RFC 4253: The Secure Shell (SSH) Transport Layer Protocol";
       container host-key {
         description
           "Parameters regarding host key.";
         leaf-list host-key-alg {

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           type identityref {
             base sshpka:public-key-alg-base;
           }
           ordered-by user;
           description
             "Acceptable host key algorithms in order of descending
              preference.  The configured host key algorithms should
              be compatible with the algorithm used by the configured
              private key.  Please see Section 5 of RFC EEEE for
              valid combinations.

              If this leaf-list is not configured (has zero elements)
              the acceptable host key algorithms are implementation-
              defined.";
           reference
             "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
         }
       }
       container key-exchange {
         description
           "Parameters regarding key exchange.";
         leaf-list key-exchange-alg {
           type identityref {
             base sshkea:key-exchange-alg-base;
           }
           ordered-by user;
           description
             "Acceptable key exchange algorithms in order of descending
              preference.

              If this leaf-list is not configured (has zero elements)
              the acceptable key exchange algorithms are implementation
              defined.";
         }
       }
       container encryption {
         description
           "Parameters regarding encryption.";
         leaf-list encryption-alg {
           type identityref {
             base sshea:encryption-alg-base;
           }
           ordered-by user;
           description
             "Acceptable encryption algorithms in order of descending
              preference.

              If this leaf-list is not configured (has zero elements)

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              the acceptable encryption algorithms are implementation
              defined.";
         }
       }
       container mac {
         description
           "Parameters regarding message authentication code (MAC).";
         leaf-list mac-alg {
           type identityref {
             base sshma:mac-alg-base;
           }
           ordered-by user;
           description
             "Acceptable MAC algorithms in order of descending
              preference.

              If this leaf-list is not configured (has zero elements)
              the acceptable MAC algorithms are implementation-
              defined.";
         }
       }
     }

   }

   <CODE ENDS>

3.  The "ietf-ssh-client" Module

   This section defines a YANG 1.1 [RFC7950] module called "ietf-ssh-
   client".  A high-level overview of the module is provided in
   Section 3.1.  Examples illustrating the module's use are provided in
   Examples (Section 3.2).  The YANG module itself is defined in
   Section 3.3.

3.1.  Data Model Overview

   This section provides an overview of the "ietf-ssh-client" module in
   terms of its features and groupings.

3.1.1.  Features

   The following diagram lists all the "feature" statements defined in
   the "ietf-ssh-client" module:

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   Features:
     +-- ssh-client-keepalives
     +-- client-ident-password
     +-- client-ident-publickey
     +-- client-ident-hostbased
     +-- client-ident-none

      |  The diagram above uses syntax that is similar to but not
      |  defined in [RFC8340].

3.1.2.  Groupings

   The "ietf-ssh-client" module defines the following "grouping"
   statement:

   *  ssh-client-grouping

   This grouping is presented in the following subsection.

3.1.2.1.  The "ssh-client-grouping" Grouping

   The following tree diagram [RFC8340] illustrates the "ssh-client-
   grouping" grouping:

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   =============== NOTE: '\' line wrapping per RFC 8792 ================

     grouping ssh-client-grouping
       +-- client-identity
       |  +-- username?      string
       |  +-- public-key! {client-ident-publickey}?
       |  |  +---u ks:local-or-keystore-asymmetric-key-grouping
       |  +-- password! {client-ident-password}?
       |  |  +---u ct:password-grouping
       |  +-- hostbased! {client-ident-hostbased}?
       |  |  +---u ks:local-or-keystore-asymmetric-key-grouping
       |  +-- none?          empty {client-ident-none}?
       |  +-- certificate! {sshcmn:ssh-x509-certs}?
       |     +---u ks:local-or-keystore-end-entity-cert-with-key-groupi\
   ng
       +-- server-authentication
       |  +-- ssh-host-keys!
       |  |  +---u ts:local-or-truststore-public-keys-grouping
       |  +-- ca-certs! {sshcmn:ssh-x509-certs}?
       |  |  +---u ts:local-or-truststore-certs-grouping
       |  +-- ee-certs! {sshcmn:ssh-x509-certs}?
       |     +---u ts:local-or-truststore-certs-grouping
       +-- transport-params {sshcmn:transport-params}?
       |  +---u sshcmn:transport-params-grouping
       +-- keepalives! {ssh-client-keepalives}?
          +-- max-wait?       uint16
          +-- max-attempts?   uint8

   Comments:

   *  The "client-identity" node configures a "username" and
      authentication methods, each enabled by a "feature" statement
      defined in Section 3.1.1.

   *  The "server-authentication" node configures trust anchors for
      authenticating the SSH server, with each option enabled by a
      "feature" statement.

   *  The "transport-params" node, which must be enabled by a feature,
      configures parameters for the SSH sessions established by this
      configuration.

   *  The "keepalives" node, which must be enabled by a feature,
      configures a "presence" container for testing the aliveness of the
      SSH server.  The aliveness-test occurs at the SSH protocol layer.

   *  For the referenced grouping statement(s):

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      -  The "local-or-keystore-asymmetric-key-grouping" grouping is
         discussed in Section 2.1.3.4 of [I-D.ietf-netconf-keystore].
      -  The "local-or-keystore-end-entity-cert-with-key-grouping"
         grouping is discussed in Section 2.1.3.6 of
         [I-D.ietf-netconf-keystore].
      -  The "local-or-truststore-public-keys-grouping" grouping is
         discussed in Section 2.1.3.2 of
         [I-D.ietf-netconf-trust-anchors].
      -  The "local-or-truststore-certs-grouping" grouping is discussed
         in Section 2.1.3.1 of [I-D.ietf-netconf-trust-anchors].
      -  The "transport-params-grouping" grouping is discussed in
         Section 2.1.2.1 in this document.

3.1.3.  Protocol-accessible Nodes

   The "ietf-ssh-client" module defines only "grouping" statements that
   are used by other modules to instantiate protocol-accessible nodes.

3.2.  Example Usage

   This section presents two examples showing the "ssh-client-grouping"
   grouping populated with some data.  These examples are effectively
   the same except the first configures the client identity using a
   local key while the second uses a key configured in a keystore.  Both
   examples are consistent with the examples presented in Section 2 of
   [I-D.ietf-netconf-trust-anchors] and Section 3.2 of
   [I-D.ietf-netconf-keystore].

   The following configuration example uses local-definitions for the
   client identity and server authentication:

   =============== NOTE: '\' line wrapping per RFC 8792 ================

   <!-- The outermost element below doesn't exist in the data model. -->
   <!--  It simulates if the "grouping" were a "container" instead.  -->

   <ssh-client
     xmlns="urn:ietf:params:xml:ns:yang:ietf-ssh-client"
     xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-crypto-types"
     xmlns:algs="urn:ietf:params:xml:ns:yang:ietf-ssh-common">

     <!-- how this client will authenticate itself to the server -->
     <client-identity>
       <username>foobar</username>
       <public-key>
         <local-definition>
           <public-key-format>ct:ssh-public-key-format</public-key-form\
   at>

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           <public-key>base64encodedvalue==</public-key>
           <private-key-format>ct:rsa-private-key-format</private-key-f\
   ormat>
           <cleartext-private-key>base64encodedvalue==</cleartext-priva\
   te-key>
         </local-definition>
       </public-key>
     </client-identity>

     <!-- which host keys will this client trust -->
     <server-authentication>
       <ssh-host-keys>
         <local-definition>
           <public-key>
             <name>corp-fw1</name>
             <public-key-format>ct:ssh-public-key-format</public-key-fo\
   rmat>
             <public-key>base64encodedvalue==</public-key>
           </public-key>
           <public-key>
             <name>corp-fw2</name>
             <public-key-format>ct:ssh-public-key-format</public-key-fo\
   rmat>
             <public-key>base64encodedvalue==</public-key>
           </public-key>
         </local-definition>
       </ssh-host-keys>
       <ca-certs>
         <local-definition>
           <certificate>
             <name>Server Cert Issuer #1</name>
             <cert-data>base64encodedvalue==</cert-data>
           </certificate>
           <certificate>
             <name>Server Cert Issuer #2</name>
             <cert-data>base64encodedvalue==</cert-data>
           </certificate>
         </local-definition>
       </ca-certs>
       <ee-certs>
         <local-definition>
           <certificate>
             <name>My Application #1</name>
             <cert-data>base64encodedvalue==</cert-data>
           </certificate>
           <certificate>
             <name>My Application #2</name>
             <cert-data>base64encodedvalue==</cert-data>

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           </certificate>
         </local-definition>
       </ee-certs>
     </server-authentication>

     <keepalives>
       <max-wait>30</max-wait>
       <max-attempts>3</max-attempts>
     </keepalives>

   </ssh-client>

   The following configuration example uses keystore-references for the
   client identity and truststore-references for server authentication:
   from the keystore:

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   =============== NOTE: '\' line wrapping per RFC 8792 ================

   <!-- The outermost element below doesn't exist in the data model. -->
   <!--  It simulates if the "grouping" were a "container" instead.  -->

   <ssh-client
     xmlns="urn:ietf:params:xml:ns:yang:ietf-ssh-client"
     xmlns:algs="urn:ietf:params:xml:ns:yang:ietf-ssh-common">

     <!-- how this client will authenticate itself to the server -->
     <client-identity>
       <username>foobar</username>
       <!-- can an SSH client have move than one key?
       <public-key>
         <keystore-reference>ssh-rsa-key</keystore-reference>
       </public-key>
       -->
       <certificate>
         <keystore-reference>
           <asymmetric-key>ssh-rsa-key-with-cert</asymmetric-key>
           <certificate>ex-rsa-cert2</certificate>
         </keystore-reference>
       </certificate>
     </client-identity>

     <!-- which host-keys will this client trust -->
     <server-authentication>
       <ssh-host-keys>
         <truststore-reference>trusted-ssh-public-keys</truststore-refe\
   rence>
       </ssh-host-keys>
       <ca-certs>
         <truststore-reference>trusted-server-ca-certs</truststore-refe\
   rence>
       </ca-certs>
       <ee-certs>
         <truststore-reference>trusted-server-ee-certs</truststore-refe\
   rence>
       </ee-certs>
     </server-authentication>

     <keepalives>
       <max-wait>30</max-wait>
       <max-attempts>3</max-attempts>
     </keepalives>

   </ssh-client>

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3.3.  YANG Module

   This YANG module has normative references to
   [I-D.ietf-netconf-trust-anchors], and [I-D.ietf-netconf-keystore].

   <CODE BEGINS> file "ietf-ssh-client@2021-06-18.yang"

   module ietf-ssh-client {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-ssh-client";
     prefix sshc;

     import ietf-netconf-acm {
       prefix nacm;
       reference
         "RFC 8341: Network Configuration Access Control Model";
     }

     import ietf-crypto-types {
       prefix ct;
       reference
         "RFC AAAA: YANG Data Types and Groupings for Cryptography";
     }

     import ietf-truststore {
       prefix ts;
       reference
         "RFC BBBB: A YANG Data Model for a Truststore";
     }

     import ietf-keystore {
       prefix ks;
       reference
         "RFC CCCC: A YANG Data Model for a Keystore";
     }

     import ietf-ssh-common {
       prefix sshcmn;
       revision-date 2021-06-18; // stable grouping definitions
       reference
         "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
     }

     organization
       "IETF NETCONF (Network Configuration) Working Group";

     contact
       "WG Web:   <http://datatracker.ietf.org/wg/netconf/>

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        WG List:  <mailto:netconf@ietf.org>
        Author:   Kent Watsen <mailto:kent+ietf@watsen.net>
        Author:   Gary Wu <mailto:garywu@cisco.com>";

     description
       "This module defines reusable groupings for SSH clients that
        can be used as a basis for specific SSH client instances.

        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 EEEE
        (https://www.rfc-editor.org/info/rfcEEEE); 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 2021-06-18 {
       description
         "Initial version";
       reference
         "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
     }

     // Features

     feature ssh-client-keepalives {
       description
         "Per socket SSH keepalive parameters are configurable for
          SSH clients on the server implementing this feature.";
     }

     feature client-ident-publickey {
       description
         "Indicates that the 'publickey' authentication type, per
          RFC 4252, is supported for client identification.

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          The 'publickey' authentication type is required by
          RFC 4252, but common implementations enable it to
          be disabled.";
       reference
         "RFC 4252:
           The Secure Shell (SSH) Authentication Protocol";
     }

     feature client-ident-password {
       description
         "Indicates that the 'password' authentication type, per
          RFC 4252, is supported for client identification.";
       reference
         "RFC 4252:
           The Secure Shell (SSH) Authentication Protocol";
     }

     feature client-ident-hostbased {
       description
         "Indicates that the 'hostbased' authentication type, per
          RFC 4252, is supported for client identification.";
       reference
         "RFC 4252:
           The Secure Shell (SSH) Authentication Protocol";
     }

     feature client-ident-none {
       description
         "Indicates that the 'none' authentication type, per
          RFC 4252, is supported for client identification.";
       reference
         "RFC 4252:
           The Secure Shell (SSH) Authentication Protocol";
     }

     // Groupings

     grouping ssh-client-grouping {
       description
         "A reusable grouping for configuring a SSH client without
          any consideration for how an underlying TCP session is
          established.

          Note that this grouping uses fairly typical descendant
          node names such that a stack of 'uses' statements will
          have name conflicts.  It is intended that the consuming
          data model will resolve the issue (e.g., by wrapping
          the 'uses' statement in a container called

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          'ssh-client-parameters').  This model purposely does
          not do this itself so as to provide maximum flexibility
          to consuming models.";

       container client-identity {
         nacm:default-deny-write;
         description
           "The username and authentication methods for the client.
            The authentication methods are unordered.  Clients may
            initially send any configured method or, per RFC 4252,
            Section 5.2, send the 'none' method to prompt the server
            to provide a list of productive methods.  Whenever a
            choice amongst methods arises, implementations SHOULD
            use a default ordering that prioritizes automation
            over human-interaction.";
         leaf username {
           type string;
           description
             "The username of this user.  This will be the username
              used, for instance, to log into an SSH server.";
         }
         container public-key {
           if-feature "client-ident-publickey";
           presence
             "Indicates that publickey-based authentication has been
              configured.  This statement is present so the mandatory
              descendent nodes do not imply that this node must be
              configured.";
           description
             "A locally-defined or referenced asymmetric key
              pair to be used for client identification.";
           reference
             "RFC CCCC: A YANG Data Model for a Keystore";
           uses ks:local-or-keystore-asymmetric-key-grouping {
             refine "local-or-keystore/local/local-definition" {
               must 'public-key-format = "ct:ssh-public-key-format"';
             }
             refine "local-or-keystore/keystore/keystore-reference" {
               must 'deref(.)/../ks:public-key-format'
                  + ' = "ct:ssh-public-key-format"';
             }
           }
         }
         container password {
           if-feature "client-ident-password";
           presence
             "Indicates that password-based authentication has been
              configured.  This statement is present so the mandatory

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              descendent nodes do not imply that this node must be
              configured.";
           description
             "A password to be used to authenticate the client's
              identity.";
           uses ct:password-grouping;
         }
         container hostbased {
           if-feature "client-ident-hostbased";
           presence
             "Indicates that hostbased authentication is configured.
              This statement is present so the mandatory descendent
              nodes do not imply that this node must be configured.";
           description
             "A locally-defined or referenced asymmetric key
              pair to be used for host identification.";
           reference
             "RFC CCCC: A YANG Data Model for a Keystore";
           uses ks:local-or-keystore-asymmetric-key-grouping {
             refine "local-or-keystore/local/local-definition" {
               must 'public-key-format = "ct:ssh-public-key-format"';
             }
             refine "local-or-keystore/keystore/keystore-reference" {
               must 'deref(.)/../ks:public-key-format'
                  + ' = "ct:ssh-public-key-format"';
             }
           }
         }
         leaf none {
           if-feature "client-ident-none";
           type empty;
           description
             "Indicates that 'none' algorithm is used for client
              identification.";
         }
         container certificate {
           if-feature "sshcmn:ssh-x509-certs";
           presence
             "Indicates that certificate-based authentication has been
              configured.  This statement is present so the mandatory
              descendant nodes do not imply that this node must be
              configured.";
           description
             "A locally-defined or referenced certificate
              to be used for client identification.";
           reference
             "RFC CCCC: A YANG Data Model for a Keystore";
           uses ks:local-or-keystore-end-entity-cert-with-key-grouping {

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             refine "local-or-keystore/local/local-definition" {
               must 'public-key-format'
                  + ' = "ct:subject-public-key-info-format"';
             }
             refine "local-or-keystore/keystore/keystore-reference"
                  + "/asymmetric-key" {
               must 'deref(.)/../ks:public-key-format'
                  + ' = "ct:subject-public-key-info-format"';
             }
           }
         }
       } // container client-identity

       container server-authentication {
         nacm:default-deny-write;
         must 'ssh-host-keys or ca-certs or ee-certs';
         description
           "Specifies how the SSH client can authenticate SSH servers.
            Any combination of authentication methods is additive and
            unordered.";
         container ssh-host-keys {
           presence
             "Indicates that the SSH host key have been configured.
              This statement is present so the mandatory descendant
              nodes do not imply that this node must be configured.";
           description
             "A bag of SSH host keys used by the SSH client to
              authenticate SSH server host keys.  A server host key
              is authenticated if it is an exact match to a
              configured SSH host key.";
           reference
             "RFC BBBB: A YANG Data Model for a Truststore";
           uses ts:local-or-truststore-public-keys-grouping {
             refine
               "local-or-truststore/local/local-definition/public-key" {
               must 'public-key-format = "ct:ssh-public-key-format"';
             }
             refine
               "local-or-truststore/truststore/truststore-reference" {
               must 'deref(.)/../*/ts:public-key-format'
                  + ' = "ct:ssh-public-key-format"';
             }
           }
         }
         container ca-certs {
           if-feature "sshcmn:ssh-x509-certs";
           presence
             "Indicates that the CA certificates have been configured.

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              This statement is present so the mandatory descendant
              nodes do not imply that this node must be configured.";
           description
             "A set of certificate authority (CA) certificates used by
              the SSH client to authenticate SSH servers.  A server
              is authenticated if its certificate  has a valid chain
              of trust to a configured CA certificate.";
           reference
             "RFC BBBB: A YANG Data Model for a Truststore";
           uses ts:local-or-truststore-certs-grouping;
         }
         container ee-certs {
           if-feature "sshcmn:ssh-x509-certs";
           presence
             "Indicates that the 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 end-entity certificates used by the SSH client
              to authenticate SSH servers.  A server is authenticated
              if its certificate is an exact match to a configured
              end-entity certificate.";
           reference
             "RFC BBBB: A YANG Data Model for a Truststore";
           uses ts:local-or-truststore-certs-grouping;
         }
       } // container server-authentication

       container transport-params {
         nacm:default-deny-write;
         if-feature "sshcmn:transport-params";
         description
           "Configurable parameters of the SSH transport layer.";
         uses sshcmn:transport-params-grouping;
       } // container transport-parameters

       container keepalives {
         nacm:default-deny-write;
         if-feature "ssh-client-keepalives";
         presence
           "Indicates that the SSH client proactively tests the
            aliveness of the remote SSH server.";
         description
           "Configures the keep-alive policy, to proactively test
            the aliveness of the SSH server.  An unresponsive TLS
            server is dropped after approximately max-wait *
            max-attempts seconds.  Per Section 4 of RFC 4254,
            the SSH client SHOULD send an SSH_MSG_GLOBAL_REQUEST

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            message with a purposely nonexistent 'request name'
            value (e.g., keepalive@ietf.org) and the 'want reply'
            value set to '1'.";
         reference
           "RFC 4254: The Secure Shell (SSH) Connection Protocol";
         leaf max-wait {
           type uint16 {
             range "1..max";
           }
           units "seconds";
           default "30";
           description
             "Sets the amount of time in seconds after which if
              no data has been received from the SSH server, a
              TLS-level message will be sent to test the
              aliveness of the SSH server.";
         }
         leaf max-attempts {
           type uint8;
           default "3";
           description
             "Sets the maximum number of sequential keep-alive
              messages that can fail to obtain a response from
              the SSH server before assuming the SSH server is
              no longer alive.";
         }
       } // container keepalives
     } // grouping ssh-client-grouping

   }

   <CODE ENDS>

4.  The "ietf-ssh-server" Module

   This section defines a YANG 1.1 module called "ietf-ssh-server".  A
   high-level overview of the module is provided in Section 4.1.
   Examples illustrating the module's use are provided in Examples
   (Section 4.2).  The YANG module itself is defined in Section 4.3.

4.1.  Data Model Overview

   This section provides an overview of the "ietf-ssh-server" module in
   terms of its features and groupings.

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4.1.1.  Features

   The following diagram lists all the "feature" statements defined in
   the "ietf-ssh-server" module:

   Features:
     +-- ssh-server-keepalives
     +-- local-users-supported
     +-- local-user-auth-publickey {local-users-supported}?
     +-- local-user-auth-password {local-users-supported}?
     +-- local-user-auth-hostbased {local-users-supported}?
     +-- local-user-auth-none {local-users-supported}?

      |  The diagram above uses syntax that is similar to but not
      |  defined in [RFC8340].

4.1.2.  Groupings

   The "ietf-ssh-server" module defines the following "grouping"
   statement:

   *  ssh-server-grouping

   This grouping is presented in the following subsection.

4.1.2.1.  The "ssh-server-grouping" Grouping

   The following tree diagram [RFC8340] illustrates the "ssh-server-
   grouping" grouping:

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   =============== NOTE: '\' line wrapping per RFC 8792 ================

     grouping ssh-server-grouping
       +-- server-identity
       |  +-- host-key* [name]
       |     +-- name?                string
       |     +-- (host-key-type)
       |        +--:(public-key)
       |        |  +-- public-key
       |        |     +---u ks:local-or-keystore-asymmetric-key-grouping
       |        +--:(certificate)
       |           +-- certificate {sshcmn:ssh-x509-certs}?
       |              +---u ks:local-or-keystore-end-entity-cert-with-k\
   ey-grouping
       +-- client-authentication
       |  +-- users {local-users-supported}?
       |  |  +-- user* [name]
       |  |     +-- name?          string
       |  |     +-- public-keys! {local-user-auth-publickey}?
       |  |     |  +---u ts:local-or-truststore-public-keys-grouping
       |  |     +-- password?      ianach:crypt-hash
       |  |     |       {local-user-auth-password}?
       |  |     +-- hostbased! {local-user-auth-hostbased}?
       |  |     |  +---u ts:local-or-truststore-public-keys-grouping
       |  |     +-- none?          empty {local-user-auth-none}?
       |  +-- ca-certs! {sshcmn:ssh-x509-certs}?
       |  |  +---u ts:local-or-truststore-certs-grouping
       |  +-- ee-certs! {sshcmn:ssh-x509-certs}?
       |     +---u ts:local-or-truststore-certs-grouping
       +-- transport-params {sshcmn:transport-params}?
       |  +---u sshcmn:transport-params-grouping
       +-- keepalives! {ssh-server-keepalives}?
          +-- max-wait?       uint16
          +-- max-attempts?   uint8

   Comments:

   *  The "server-identity" node configures the authentication methods
      the server can use to identify itself to clients.  The ability to
      use a certificate is enabled by a "feature".

   *  The "client-authentication" node configures trust anchors for
      authenticating the SSH client, with each option enabled by a
      "feature" statement.

   *  The "transport-params" node, which must be enabled by a feature,
      configures parameters for the SSH sessions established by this
      configuration.

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   *  The "keepalives" node, which must be enabled by a feature,
      configures a "presence" container for testing the aliveness of the
      SSH client.  The aliveness-test occurs at the SSH protocol layer.

   *  For the referenced grouping statement(s):

      -  The "local-or-keystore-asymmetric-key-grouping" grouping is
         discussed in Section 2.1.3.4 of [I-D.ietf-netconf-keystore].
      -  The "local-or-keystore-end-entity-cert-with-key-grouping"
         grouping is discussed in Section 2.1.3.6 of
         [I-D.ietf-netconf-keystore].
      -  The "local-or-truststore-public-keys-grouping" grouping is
         discussed in Section 2.1.3.2 of
         [I-D.ietf-netconf-trust-anchors].
      -  The "local-or-truststore-certs-grouping" grouping is discussed
         in Section 2.1.3.1 of [I-D.ietf-netconf-trust-anchors].
      -  The "transport-params-grouping" grouping is discussed in
         Section 2.1.2.1 in this document.

4.1.3.  Protocol-accessible Nodes

   The "ietf-ssh-server" module defines only "grouping" statements that
   are used by other modules to instantiate protocol-accessible nodes.

4.2.  Example Usage

   This section presents two examples showing the "ssh-server-grouping"
   grouping populated with some data.  These examples are effectively
   the same except the first configures the server identity using a
   local key while the second uses a key configured in a keystore.  Both
   examples are consistent with the examples presented in Section 2 of
   [I-D.ietf-netconf-trust-anchors] and Section 3.2 of
   [I-D.ietf-netconf-keystore].

   The following configuration example uses local-definitions for the
   server identity and client authentication:

   =============== NOTE: '\' line wrapping per RFC 8792 ================

   <!-- The outermost element below doesn't exist in the data model. -->
   <!--  It simulates if the "grouping" were a "container" instead.  -->

   <ssh-server
     xmlns="urn:ietf:params:xml:ns:yang:ietf-ssh-server"
     xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-crypto-types"
     xmlns:algs="urn:ietf:params:xml:ns:yang:ietf-ssh-common">

     <!-- the host-key this SSH server will present -->

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     <server-identity>
       <host-key>
         <name>my-pubkey-based-host-key</name>
         <public-key>
           <local-definition>
             <public-key-format>ct:ssh-public-key-format</public-key-fo\
   rmat>
             <public-key>base64encodedvalue==</public-key>
             <private-key-format>ct:rsa-private-key-format</private-key\
   -format>
             <cleartext-private-key>base64encodedvalue==</cleartext-pri\
   vate-key>
           </local-definition>
         </public-key>
       </host-key>
       <host-key>
         <name>my-cert-based-host-key</name>
         <certificate>
           <local-definition>
             <public-key-format>ct:subject-public-key-info-format</publ\
   ic-key-format>
             <public-key>base64encodedvalue==</public-key>
             <private-key-format>ct:rsa-private-key-format</private-key\
   -format>
             <cleartext-private-key>base64encodedvalue==</cleartext-pri\
   vate-key>
             <cert-data>base64encodedvalue==</cert-data>
           </local-definition>
         </certificate>
       </host-key>
     </server-identity>

     <!-- the client credentials this SSH server will trust -->
     <client-authentication>
       <users>
         <user>
           <name>mary</name>
           <password>$0$secret</password>
           <public-keys>
             <local-definition>
               <public-key>
                 <name>User A</name>
                 <public-key-format>ct:ssh-public-key-format</public-ke\
   y-format>
                 <public-key>base64encodedvalue==</public-key>
               </public-key>
               <public-key>
                 <name>User B</name>

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                 <public-key-format>ct:ssh-public-key-format</public-ke\
   y-format>
                 <public-key>base64encodedvalue==</public-key>
               </public-key>
             </local-definition>
           </public-keys>
         </user>
       </users>
       <ca-certs>
         <local-definition>
           <certificate>
             <name>Identity Cert Issuer #1</name>
             <cert-data>base64encodedvalue==</cert-data>
           </certificate>
           <certificate>
             <name>Identity Cert Issuer #2</name>
             <cert-data>base64encodedvalue==</cert-data>
           </certificate>
         </local-definition>
       </ca-certs>
       <ee-certs>
         <local-definition>
           <certificate>
             <name>Application #1</name>
             <cert-data>base64encodedvalue==</cert-data>
           </certificate>
           <certificate>
             <name>Application #2</name>
             <cert-data>base64encodedvalue==</cert-data>
           </certificate>
         </local-definition>
       </ee-certs>
     </client-authentication>

     <keepalives>
       <max-wait>30</max-wait>
       <max-attempts>3</max-attempts>
     </keepalives>

   </ssh-server>

   The following configuration example uses keystore-references for the
   server identity and truststore-references for client authentication:
   from the keystore:

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   =============== NOTE: '\' line wrapping per RFC 8792 ================

   <!-- The outermost element below doesn't exist in the data model. -->
   <!--  It simulates if the "grouping" were a "container" instead.  -->

   <ssh-server
     xmlns="urn:ietf:params:xml:ns:yang:ietf-ssh-server"
     xmlns:algs="urn:ietf:params:xml:ns:yang:ietf-ssh-common">

     <!-- the host-key this SSH server will present -->
     <server-identity>
       <host-key>
         <name>my-pubkey-based-host-key</name>
         <public-key>
           <keystore-reference>ssh-rsa-key</keystore-reference>
         </public-key>
       </host-key>
       <host-key>
         <name>my-cert-based-host-key</name>
         <certificate>
           <keystore-reference>
             <asymmetric-key>ssh-rsa-key-with-cert</asymmetric-key>
             <certificate>ex-rsa-cert2</certificate>
           </keystore-reference>
         </certificate>
       </host-key>
     </server-identity>

     <!-- the client credentials this SSH server will trust -->
     <client-authentication>
       <users>
         <user>
           <name>mary</name>
           <password>$0$secret</password>
           <public-keys>
             <truststore-reference>SSH Public Keys for Application A</t\
   ruststore-reference>
           </public-keys>
         </user>
       </users>
       <ca-certs>
         <truststore-reference>trusted-client-ca-certs</truststore-refe\
   rence>
       </ca-certs>
       <ee-certs>
         <truststore-reference>trusted-client-ee-certs</truststore-refe\
   rence>
       </ee-certs>

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     </client-authentication>

     <keepalives>
       <max-wait>30</max-wait>
       <max-attempts>3</max-attempts>
     </keepalives>

   </ssh-server>

4.3.  YANG Module

   This YANG module has normative references to
   [I-D.ietf-netconf-trust-anchors] and [I-D.ietf-netconf-keystore] and
   informative references to [RFC4253] and [RFC7317].

   <CODE BEGINS> file "ietf-ssh-server@2021-06-18.yang"

   module ietf-ssh-server {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-ssh-server";
     prefix sshs;

     import iana-crypt-hash {
       prefix ianach;
       reference
         "RFC 7317: A YANG Data Model for System Management";
     }

     import ietf-netconf-acm {
       prefix nacm;
       reference
         "RFC 8341: Network Configuration Access Control Model";
     }

     import ietf-crypto-types {
       prefix ct;
       reference
         "RFC AAAA: YANG Data Types and Groupings for Cryptography";
     }

     import ietf-truststore {
       prefix ts;
       reference
         "RFC BBBB: A YANG Data Model for a Truststore";
     }

     import ietf-keystore {
       prefix ks;

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       reference
         "RFC CCCC: A YANG Data Model for a Keystore";
     }

     import ietf-ssh-common {
       prefix sshcmn;
       revision-date 2021-06-18; // stable grouping definitions
       reference
         "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
     }

     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>
        Author:   Gary Wu <mailto:garywu@cisco.com>";

     description
       "This module defines reusable groupings for SSH servers that
        can be used as a basis for specific SSH server instances.

        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 EEEE
        (https://www.rfc-editor.org/info/rfcEEEE); 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 2021-06-18 {
       description
         "Initial version";

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       reference
         "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
     }

     // Features

     feature ssh-server-keepalives {
       description
         "Per socket SSH keepalive parameters are configurable for
          SSH servers on the server implementing this feature.";
     }

     feature local-users-supported {
       description
         "Indicates that the configuration for users can be
          configured herein, as opposed to in an application
          specific location.";
     }

     feature local-user-auth-publickey {
       if-feature "local-users-supported";
       description
         "Indicates that the 'publickey' authentication type,
          per RFC 4252, is supported for locally-defined users.

          The 'publickey' authentication type is required by
          RFC 4252, but common implementations enable it to
          be disabled.";
       reference
         "RFC 4252:
           The Secure Shell (SSH) Authentication Protocol";
     }

     feature local-user-auth-password {
       if-feature "local-users-supported";
       description
         "Indicates that the 'password' authentication type,
          per RFC 4252, is supported for locally-defined users.";
       reference
         "RFC 4252:
           The Secure Shell (SSH) Authentication Protocol";
     }

     feature local-user-auth-hostbased {
       if-feature "local-users-supported";
       description
         "Indicates that the 'hostbased' authentication type,
          per RFC 4252, is supported for locally-defined users.";

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       reference
         "RFC 4252:
           The Secure Shell (SSH) Authentication Protocol";
     }

     feature local-user-auth-none {
       if-feature "local-users-supported";
       description
         "Indicates that the 'none' authentication type, per
          RFC 4252, is supported.  It is NOT RECOMMENDED to
          enable this feature.";
       reference
         "RFC 4252:
           The Secure Shell (SSH) Authentication Protocol";
     }

     // Groupings

     grouping ssh-server-grouping {
       description
         "A reusable grouping for configuring a SSH server without
          any consideration for how underlying TCP sessions are
          established.

          Note that this grouping uses fairly typical descendant
          node names such that a stack of 'uses' statements will
          have name conflicts.  It is intended that the consuming
          data model will resolve the issue (e.g., by wrapping
          the 'uses' statement in a container called
          'ssh-server-parameters').  This model purposely does
          not do this itself so as to provide maximum flexibility
          to consuming models.";

       container server-identity {
         nacm:default-deny-write;
         description
           "The list of host keys the SSH server will present when
            establishing a SSH connection.";
         list host-key {
           key "name";
           min-elements 1;
           ordered-by user;
           description
             "An ordered list of host keys the SSH server will use to
              construct its ordered list of algorithms, when sending
              its SSH_MSG_KEXINIT message, as defined in Section 7.1
              of RFC 4253.";
           reference

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             "RFC 4253: The Secure Shell (SSH) Transport Layer
                        Protocol";
           leaf name {
             type string;
             description
               "An arbitrary name for this host key";
           }
           choice host-key-type {
             mandatory true;
             description
               "The type of host key being specified";
             container public-key {
               description
                 "A locally-defined or referenced asymmetric key pair
                  to be used for the SSH server's host key.";
               reference
                 "RFC CCCC: A YANG Data Model for a Keystore";
               uses ks:local-or-keystore-asymmetric-key-grouping {
                 refine "local-or-keystore/local/local-definition" {
                   must
                     'public-key-format = "ct:ssh-public-key-format"';
                 }
                 refine "local-or-keystore/keystore/"
                      + "keystore-reference" {
                   must 'deref(.)/../ks:public-key-format'
                      + ' = "ct:ssh-public-key-format"';
                 }
               }
             }
             container certificate {
               if-feature "sshcmn:ssh-x509-certs";
               description
                 "A locally-defined or referenced end-entity
                  certificate to be used for the SSH server's
                  host key.";
               reference
                 "RFC CCCC: A YANG Data Model for a Keystore";
               uses
               ks:local-or-keystore-end-entity-cert-with-key-grouping {
                 refine "local-or-keystore/local/local-definition" {
                   must 'public-key-format'
                      + ' = "ct:subject-public-key-info-format"';
                 }
                 refine "local-or-keystore/keystore/keystore-reference"
                        + "/asymmetric-key" {
                   must 'deref(.)/../ks:public-key-format'
                        + ' = "ct:subject-public-key-info-format"';
                 }

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               }
             }
           }
         }
       } // container server-identity

       container client-authentication {
         nacm:default-deny-write;
         description
           "Specifies how the SSH server can authenticate SSH clients.";
         container users {
           if-feature "local-users-supported";
           description
             "A list of locally configured users.";
           list user {
             key "name";
             description
               "A locally configured user.

                The server SHOULD derive the list of authentication
                'method names' returned to the SSH client from the
                descendant nodes configured herein, per Sections
                5.1 and 5.2 in RFC 4252.

                The authentication methods are unordered.  Clients
                must authenticate to all configured methods.
                Whenever a choice amongst methods arises,
                implementations SHOULD use a default ordering
                that prioritizes automation over human-interaction.";
             leaf name {
               type string;
               description
                 "The 'user name' for the SSH client, as defined in
                  the SSH_MSG_USERAUTH_REQUEST message in RFC 4253.";
             }
             container public-keys {
               if-feature "local-user-auth-publickey";
               presence
                 "Indicates that 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 SSH public keys may be used by the SSH
                  server to authenticate this user.  A user is
                  authenticated if its public key is an exact
                  match to a configured public key.";
               reference

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                 "RFC BBBB: A YANG Data Model for a Truststore";
               uses ts:local-or-truststore-public-keys-grouping {
                 refine "local-or-truststore/local/local-definition"
                        + "/public-key" {
                   must 'public-key-format'
                        + ' = "ct:ssh-public-key-format"';
                 }
                 refine "local-or-truststore/truststore/"
                        + "truststore-reference" {
                   must 'deref(.)/../*/ts:public-key-format'
                        + ' = "ct:ssh-public-key-format"';
                 }
               }
             }
             leaf password {
               if-feature "local-user-auth-password";
               type ianach:crypt-hash;
               description
                 "The password for this user.";
             }
             container hostbased {
               if-feature "local-user-auth-hostbased";
               presence
                 "Indicates that hostbased 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 SSH host keys used by the SSH server to
                  authenticate this user's host.  A user's host is
                  authenticated if its host key is an exact match
                  to a configured host key.";
               reference
                 "RFC 4253: The Secure Shell (SSH) Transport Layer
                  RFC BBBB: A YANG Data Model for a Truststore";
               uses ts:local-or-truststore-public-keys-grouping {
                 refine "local-or-truststore/local/local-definition"
                        + "/public-key" {
                   must 'public-key-format'
                        + ' = "ct:ssh-public-key-format"';
                 }
                 refine "local-or-truststore/truststore"
                        + "/truststore-reference" {
                   must 'deref(.)/../*/ts:public-key-format'
                        + ' = "ct:ssh-public-key-format"';
                 }
               }
             }

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             leaf none {
               if-feature "local-user-auth-none";
               type empty;
               description
                 "Indicates that the 'none' method is configured
                  for this user.";
               reference
                 "RFC 4252: The Secure Shell (SSH) Authentication
                            Protocol.";
             }
           }
         }
         container ca-certs {
           if-feature "sshcmn:ssh-x509-certs";
           presence
             "Indicates that CA certificates have been configured.
              This statement is present so the mandatory descendant
              nodes do not imply this node must be configured.";
           description
             "A set of certificate authority (CA) certificates used by
              the SSH server to authenticate SSH client certificates.
              A client certificate is authenticated if it has a valid
              chain of trust to a configured CA certificate.";
           reference
             "RFC BBBB: A YANG Data Model for a Truststore";
           uses ts:local-or-truststore-certs-grouping;
         }
         container ee-certs {
           if-feature "sshcmn:ssh-x509-certs";
           presence
             "Indicates that EE certificates have been configured.
              This statement is present so the mandatory descendant
              nodes do not imply this node must be configured.";
           description
             "A set of client certificates (i.e., end entity
              certificates) used by the SSH server to authenticate
              the certificates presented by SSH clients.  A client
              certificate is authenticated if it is an exact match
              to a configured end-entity certificate.";
           reference
             "RFC BBBB: A YANG Data Model for a Truststore";
           uses ts:local-or-truststore-certs-grouping;
         }
       } // container client-authentication

       container transport-params {
         nacm:default-deny-write;
         if-feature "sshcmn:transport-params";

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         description
           "Configurable parameters of the SSH transport layer.";
         uses sshcmn:transport-params-grouping;
       } // container transport-params

       container keepalives {
         nacm:default-deny-write;
         if-feature "ssh-server-keepalives";
         presence
           "Indicates that the SSH server proactively tests the
            aliveness of the remote SSH client.";
         description
           "Configures the keep-alive policy, to proactively test
            the aliveness of the SSL client.  An unresponsive SSL
            client is dropped after approximately max-wait *
            max-attempts seconds.  Per Section 4 of RFC 4254,
            the SSH server SHOULD send an SSH_MSG_GLOBAL_REQUEST
            message with a purposely nonexistent 'request name'
            value (e.g., keepalive@ietf.org) and the 'want reply'
            value set to '1'.";
         reference
           "RFC 4254: The Secure Shell (SSH) Connection Protocol";
         leaf max-wait {
           type uint16 {
             range "1..max";
           }
           units "seconds";
           default "30";
           description
             "Sets the amount of time in seconds after which
              if no data has been received from the SSL client,
              a SSL-level message will be sent to test the
              aliveness of the SSL client.";
         }
         leaf max-attempts {
           type uint8;
           default "3";
           description
             "Sets the maximum number of sequential keep-alive
              messages that can fail to obtain a response from
              the SSL client before assuming the SSL client is
              no longer alive.";
         }
       }
     } // grouping ssh-server-grouping

   }

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   <CODE ENDS>

5.  Security Considerations

5.1.  The "iana-ssh-key-exchange-algs" Module

   The "iana-ssh-key-exchange-algs" YANG module defines a data model
   that is designed to be accessed via YANG based management protocols,
   such as NETCONF [RFC6241] and RESTCONF [RFC8040].  Both of these
   protocols have mandatory-to-implement secure transport layers (e.g.,
   SSH, TLS) with mutual authentication.

   The 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.

   This YANG module defines YANG identities, for a public IANA-
   maintained registry, and a single protocol-accessible read-only node
   for the subset of those identities supported by a server.

   YANG identities are not security-sensitive, as they are statically
   defined in the publicly-accessible YANG module.

   The protocol-accessible read-only node for the algorithms supported
   by a server is mildly sensitive, but not to the extent that special
   NACM annotations are needed to prevent read-access to regular
   authenticated administrators.

   This module does not define any writable-nodes, RPCs, actions, or
   notifications, and thus the security consideration for such is not
   provided here.

5.2.  The "iana-ssh-encryption-algs" Module

   The "iana-ssh-encryption-algs" YANG module defines a data model that
   is designed to be accessed via YANG based management protocols, such
   as NETCONF [RFC6241] and RESTCONF [RFC8040].  Both of these protocols
   have mandatory-to-implement secure transport layers (e.g., SSH, TLS)
   with mutual authentication.

   The 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.

   This YANG module defines YANG identities, for a public IANA-
   maintained registry, and a single protocol-accessible read-only node
   for the subset of those identities supported by a server.

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   YANG identities are not security-sensitive, as they are statically
   defined in the publicly-accessible YANG module.

   The protocol-accessible read-only node for the algorithms supported
   by a server is mildly sensitive, but not to the extent that special
   NACM annotations are needed to prevent read-access to regular
   authenticated administrators.

   This module does not define any writable-nodes, RPCs, actions, or
   notifications, and thus the security consideration for such is not
   provided here.

5.3.  The "iana-ssh-mac-algs" Module

   The "iana-ssh-mac-algs" YANG module defines a data model that is
   designed to be accessed via YANG based management protocols, such as
   NETCONF [RFC6241] and RESTCONF [RFC8040].  Both of these protocols
   have mandatory-to-implement secure transport layers (e.g., SSH, TLS)
   with mutual authentication.

   The 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.

   This YANG module defines YANG identities, for a public IANA-
   maintained registry, and a single protocol-accessible read-only node
   for the subset of those identities supported by a server.

   YANG identities are not security-sensitive, as they are statically
   defined in the publicly-accessible YANG module.

   The protocol-accessible read-only node for the algorithms supported
   by a server is mildly sensitive, but not to the extent that special
   NACM annotations are needed to prevent read-access to regular
   authenticated administrators.

   This module does not define any writable-nodes, RPCs, actions, or
   notifications, and thus the security consideration for such is not
   provided here.

5.4.  The "iana-ssh-public-key-algs" Module

   The "iana-ssh-public-key-algs" YANG module defines a data model that
   is designed to be accessed via YANG based management protocols, such
   as NETCONF [RFC6241] and RESTCONF [RFC8040].  Both of these protocols
   have mandatory-to-implement secure transport layers (e.g., SSH, TLS)
   with mutual authentication.

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   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.

   This YANG module defines YANG identities, for a public IANA-
   maintained registry, and a single protocol-accessible read-only node
   for the subset of those identities supported by a server.

   YANG identities are not security-sensitive, as they are statically
   defined in the publicly-accessible YANG module.

   The protocol-accessible read-only node for the algorithms supported
   by a server is mildly sensitive, but not to the extent that special
   NACM annotations are needed to prevent read-access to regular
   authenticated administrators.

   This module does not define any writable-nodes, RPCs, actions, or
   notifications, and thus the security consideration for such is not
   provided here.

5.5.  The "ietf-ssh-common" YANG Module

   The "ietf-ssh-common" YANG module 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 define groupings, these
   considerations are primarily for the designers of other modules that
   use these groupings.

   None of the readable data nodes defined in this YANG module are
   considered sensitive or vulnerable in network environments.  The NACM
   "default-deny-all" extension has not been set for any data nodes
   defined in this module.

   None of the writable data nodes defined in this YANG module are
   considered sensitive or vulnerable in network environments.  The NACM
   "default-deny-write" extension has not been set for any data nodes
   defined in this module.

   This module does not define any RPCs, actions, or notifications, and
   thus the security consideration for such is not provided here.

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5.6.  The "ietf-ssh-client" YANG Module

   The "ietf-ssh-client" YANG module 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 define groupings, these
   considerations are primarily for the designers of other modules that
   use these groupings.

   One readable data node defined in this YANG module may be considered
   sensitive or vulnerable in some network environments.  This node is
   as follows:

   *  The "client-identity/password" node:

         The cleartext "password" node defined in the "ssh-client-
         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.

      |  Please be aware that this module uses the "key" and "private-
      |  key" nodes from the "ietf-crypto-types" module
      |  [I-D.ietf-netconf-crypto-types], where said nodes have the NACM
      |  extension "default-deny-all" set, thus preventing unrestricted
      |  read-access to the cleartext key values.

   All of the writable data nodes defined by this module may be
   considered sensitive or vulnerable in some network environments.  For
   instance, any modification to a key or reference to a key may
   dramatically alter the implemented security policy.  For this reason,
   the NACM extension "default-deny-write" has been set for all data
   nodes defined in this module.

   This module does not define any RPCs, actions, or notifications, and
   thus the security consideration for such is not provided here.

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5.7.  The "ietf-ssh-server" YANG Module

   The "ietf-ssh-server" YANG module 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 define groupings, these
   considerations are primarily for the designers of other modules that
   use these groupings.

   None of the readable data nodes defined in this YANG module are
   considered sensitive or vulnerable in network environments.  The NACM
   "default-deny-all" extension has not been set for any data nodes
   defined in this module.

      |  Please be aware that this module uses the "key" and "private-
      |  key" nodes from the "ietf-crypto-types" module
      |  [I-D.ietf-netconf-crypto-types], where said nodes have the NACM
      |  extension "default-deny-all" set, thus preventing unrestricted
      |  read-access to the cleartext key values.

   All of the writable data nodes defined by this module may be
   considered sensitive or vulnerable in some network environments.  For
   instance, the addition or removal of references to keys,
   certificates, trusted anchors, etc., or even the modification of
   transport or keepalive parameters can dramatically alter the
   implemented security policy.  For this reason, the NACM extension
   "default-deny-write" has been set for all data nodes defined in this
   module.

   This module does not define any RPCs, actions, or notifications, and
   thus the security consideration for such is not provided here.

6.  IANA Considerations

6.1.  The "IETF XML" Registry

   This document registers seven URIs in the "ns" subregistry of the
   IETF XML Registry [RFC3688].  Following the format in [RFC3688], the
   following registrations are requested:

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   URI: urn:ietf:params:xml:ns:yang:iana-ssh-key-exchange-algs
   Registrant Contact: IANA
   XML: N/A, the requested URI is an XML namespace.

   URI: urn:ietf:params:xml:ns:yang:iana-ssh-encryption-algs
   Registrant Contact: IANA
   XML: N/A, the requested URI is an XML namespace.

   URI: urn:ietf:params:xml:ns:yang:iana-ssh-mac-algs
   Registrant Contact: IANA
   XML: N/A, the requested URI is an XML namespace.

   URI: urn:ietf:params:xml:ns:yang:iana-ssh-public-key-algs
   Registrant Contact: IANA
   XML: N/A, the requested URI is an XML namespace.

   URI: urn:ietf:params:xml:ns:yang:ietf-ssh-common
   Registrant Contact: The IESG
   XML: N/A, the requested URI is an XML namespace.

   URI: urn:ietf:params:xml:ns:yang:ietf-ssh-client
   Registrant Contact: The IESG
   XML: N/A, the requested URI is an XML namespace.

   URI: urn:ietf:params:xml:ns:yang:ietf-ssh-server
   Registrant Contact: The IESG
   XML: N/A, the requested URI is an XML namespace.

6.2.  The "YANG Module Names" Registry

   This document registers seven YANG modules in the YANG Module Names
   registry [RFC6020].  Following the format in [RFC6020], the following
   registrations are requested:

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   name:         iana-ssh-key-exchange-algs
   namespace:    urn:ietf:params:xml:ns:yang:iana-ssh-key-exchange-algs
   prefix:       sshkea
   reference:    RFC EEEE

   name:         iana-ssh-encryption-algs
   namespace:    urn:ietf:params:xml:ns:yang:iana-ssh-encryption-algs
   prefix:       sshea
   reference:    RFC EEEE

   name:         iana-ssh-mac-algs
   namespace:    urn:ietf:params:xml:ns:yang:iana-ssh-mac-algs
   prefix:       sshma
   reference:    RFC EEEE

   name:         iana-ssh-public-key-algs
   namespace:    urn:ietf:params:xml:ns:yang:iana-ssh-public-key-algs
   prefix:       sshpka
   reference:    RFC EEEE

   name:         ietf-ssh-common
   namespace:    urn:ietf:params:xml:ns:yang:ietf-ssh-common
   prefix:       sshcmn
   reference:    RFC EEEE

   name:         ietf-ssh-client
   namespace:    urn:ietf:params:xml:ns:yang:ietf-ssh-client
   prefix:       sshc
   reference:    RFC EEEE

   name:         ietf-ssh-server
   namespace:    urn:ietf:params:xml:ns:yang:ietf-ssh-server
   prefix:       sshs
   reference:    RFC EEEE

6.3.  The "iana-ssh-encryption-algs" Module

   IANA is requested to maintain a YANG module called "iana-ssh-
   encryption-algs" that shadows the "Encryption Algorithm Names" sub-
   registry of the "Secure Shell (SSH) Protocol Parameters" registry
   [IANA-ENC-ALGS].

   This registry defines a YANG identity for each encryption algorithm,
   and a "base" identity from which all of the other identities are
   derived.

   An initial version of this module can be found in Appendix A.1

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   *  Please note that this module was created on June 1st, 2021, and
      that additional entries may have been added in the interim before
      this document's publication.  If this is that case, IANA may
      either publish just an updated module containing the new entries,
      or publish the initial module as is immediately followed by a
      "revision" containing the additional algorithm names.

6.4.  The "iana-ssh-mac-algs" Module

   IANA is requested to maintain a YANG module called "iana-ssh-mac-
   algs" that shadows the "MAC Algorithm Names" sub-registry of the
   "Secure Shell (SSH) Protocol Parameters" registry [IANA-MAC-ALGS].

   This registry defines a YANG identity for each MAC algorithm, and a
   "base" identity from which all of the other identities are derived.

   An initial version of this module can be found in Appendix A.2.

   *  Please note that this module was created on June 1st, 2021, and
      that additional entries may have been added in the interim before
      this document's publication.  If this is that case, IANA may
      either publish just an updated module containing the new entries,
      or publish the initial module as is immediately followed by a
      "revision" containing the additional algorithm names.

6.5.  The "iana-ssh-public-key-algs" Module

   IANA is requested to maintain a YANG module called "iana-ssh-public-
   key-algs" that shadows the "Public Key Algorithm Names" sub-registry
   of the "Secure Shell (SSH) Protocol Parameters" registry
   [IANA-PUBKEY-ALGS].

   This registry defines a YANG identity for each public key algorithm,
   and a "base" identity from which all of the other identities are
   derived.

   Registry entries for which the '*All values beginning with the
   specified string and not containing "@".' note applies MUST be
   expanded so that there is a distinct YANG identity for each
   enumeration.

   An initial version of this module can be found in Appendix A.3.

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   *  Please note that this module was created on June 1st, 2021, and
      that additional entries may have been added in the interim before
      this document's publication.  If this is that case, IANA may
      either publish just an updated module containing the new entries,
      or publish the initial module as is immediately followed by a
      "revision" containing the additional algorithm names.

6.6.  The "iana-ssh-key-exchange-algs" Module

   IANA is requested to maintain a YANG module called "iana-ssh-key-
   exchange-algs" that shadows the "Key Exchange Method Names" sub-
   registry of the "Secure Shell (SSH) Protocol Parameters" registry
   [IANA-KEYEX-ALGS].

   This registry defines a YANG identity for each key exchange
   algortihm, and a "base" identity from which all of the other
   identities are derived.

   Registry entries for which the '*All values beginning with the
   specified string and not containing "@".' note applies MUST be
   expanded so that there is a distinct YANG identity for each
   enumeration.

   An initial version of this module can be found in Appendix A.4.

   *  Please note that this module was created on June 1st, 2021, and
      that additional entries may have been added in the interim before
      this document's publication.  If this is that case, IANA may
      either publish just an updated module containing the new entries,
      or publish the initial module as is immediately followed by a
      "revision" containing the additional algorithm names.

   *  Please also note that the "status" statement has been set to
      "deprecated" https://datatracker.ietf.org/doc/html/
      rfc8732#section-6.  It is recommended that IANA adds a column to
      the registry to more easily track the deprecation status of
      algorithms.

7.  References

7.1.  Normative References

   [I-D.ietf-netconf-crypto-types]
              Watsen, K., "YANG Data Types and Groupings for
              Cryptography", Work in Progress, Internet-Draft, draft-
              ietf-netconf-crypto-types-19, 10 February 2021,
              <https://tools.ietf.org/html/draft-ietf-netconf-crypto-
              types-19>.

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   [I-D.ietf-netconf-keystore]
              Watsen, K., "A YANG Data Model for a Keystore", Work in
              Progress, Internet-Draft, draft-ietf-netconf-keystore-21,
              10 February 2021, <https://tools.ietf.org/html/draft-ietf-
              netconf-keystore-21>.

   [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-14, 10 February 2021,
              <https://tools.ietf.org/html/draft-ietf-netconf-trust-
              anchors-14>.

   [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>.

   [RFC4344]  Bellare, M., Kohno, T., and C. Namprempre, "The Secure
              Shell (SSH) Transport Layer Encryption Modes", RFC 4344,
              DOI 10.17487/RFC4344, January 2006,
              <https://www.rfc-editor.org/info/rfc4344>.

   [RFC4419]  Friedl, M., Provos, N., and W. Simpson, "Diffie-Hellman
              Group Exchange for the Secure Shell (SSH) Transport Layer
              Protocol", RFC 4419, DOI 10.17487/RFC4419, March 2006,
              <https://www.rfc-editor.org/info/rfc4419>.

   [RFC5656]  Stebila, D. and J. Green, "Elliptic Curve Algorithm
              Integration in the Secure Shell Transport Layer",
              RFC 5656, DOI 10.17487/RFC5656, December 2009,
              <https://www.rfc-editor.org/info/rfc5656>.

   [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>.

   [RFC6187]  Igoe, K. and D. Stebila, "X.509v3 Certificates for Secure
              Shell Authentication", RFC 6187, DOI 10.17487/RFC6187,
              March 2011, <https://www.rfc-editor.org/info/rfc6187>.

   [RFC6668]  Bider, D. and M. Baushke, "SHA-2 Data Integrity
              Verification for the Secure Shell (SSH) Transport Layer
              Protocol", RFC 6668, DOI 10.17487/RFC6668, July 2012,
              <https://www.rfc-editor.org/info/rfc6668>.

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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>.

7.2.  Informative References

   [I-D.ietf-netconf-http-client-server]
              Watsen, K., "YANG Groupings for HTTP Clients and HTTP
              Servers", Work in Progress, Internet-Draft, draft-ietf-
              netconf-http-client-server-07, 18 May 2021,
              <https://tools.ietf.org/html/draft-ietf-netconf-http-
              client-server-07>.

   [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://tools.ietf.org/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://tools.ietf.org/html/draft-ietf-netconf-restconf-
              client-server-23>.

   [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-24, 18 May 2021,
              <https://tools.ietf.org/html/draft-ietf-netconf-ssh-
              client-server-24>.

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   [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://tools.ietf.org/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-24, 18 May 2021,
              <https://tools.ietf.org/html/draft-ietf-netconf-tls-
              client-server-24>.

   [IANA-ENC-ALGS]
              (IANA), I. A. N. A., "IANA "Encryption Algorithm Names"
              Sub-registry of the "Secure Shell (SSH) Protocol
              Parameters" Registry", <https://www.iana.org/assignments/
              ssh-parameters/ssh-parameters.xhtml#ssh-parameters-17>.

   [IANA-KEYEX-ALGS]
              (IANA), I. A. N. A., "IANA "Key Exchange Method Names"
              Sub-registry of the "Secure Shell (SSH) Protocol
              Parameters" Registry", <https://www.iana.org/assignments/
              ssh-parameters/ssh-parameters.xhtml#ssh-parameters-16>.

   [IANA-MAC-ALGS]
              (IANA), I. A. N. A., "IANA "MAC Algorithm Names" Sub-
              registry of the "Secure Shell (SSH) Protocol Parameters"
              Registry", <https://www.iana.org/assignments/ssh-
              parameters/ssh-parameters.xhtml#ssh-parameters-18>.

   [IANA-PUBKEY-ALGS]
              (IANA), I. A. N. A., "IANA "Public Key Algorithm Names"
              Sub-registry of the "Secure Shell (SSH) Protocol
              Parameters" Registry", <https://www.iana.org/assignments/
              ssh-parameters/ssh-parameters.xhtml#ssh-parameters-19>.

   [OPENSSH]  Project, T. O., "OpenSSH", <http://www.openssh.com>.

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              DOI 10.17487/RFC3688, January 2004,
              <https://www.rfc-editor.org/info/rfc3688>.

   [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/info/rfc4252>.

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   [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>.

   [RFC4254]  Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH)
              Connection Protocol", RFC 4254, DOI 10.17487/RFC4254,
              January 2006, <https://www.rfc-editor.org/info/rfc4254>.

   [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>.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011,
              <https://www.rfc-editor.org/info/rfc6242>.

   [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/info/rfc7317>.

   [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>.

   [RFC8071]  Watsen, K., "NETCONF Call Home and RESTCONF Call Home",
              RFC 8071, DOI 10.17487/RFC8071, February 2017,
              <https://www.rfc-editor.org/info/rfc8071>.

   [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.  YANG Modules for IANA

   The modules contained in this section were generated by scripts using
   the contents of the associated sub-registry as they existed on June
   1st, 2021.

A.1.  Initial Module for the "Encryption Algorithm Names" Registry

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A.1.1.  Data Model Overview

   This section provides an overview of the "iana-ssh-encryption-algs"
   module in terms of its identities and protocol-accessible nodes.

A.1.1.1.  Identities

   The following diagram lists the base "identity" statements defined in
   the module, of which there is just one, and illustrates that all the
   derived identity statements are generated from the associated IANA-
   maintained registry [IANA-ENC-ALGS].

   Identities:
     +-- encryption-alg-base
       +-- <identity-name from IANA registry>

      |  The diagram above uses syntax that is similar to but not
      |  defined in [RFC8340].

A.1.1.2.  Protocol-accessible Nodes

   The following tree diagram [RFC8340] lists all the protocol-
   accessible nodes defined in the "iana-ssh-encryption-alg" module:

   module: iana-ssh-encryption-algs
     +--ro supported-algorithms
        +--ro supported-algorithm*   identityref

   Comments:

   *  Protocol-accessible nodes are those nodes that are accessible when
      the module is "implemented", as described in Section 5.6.5 of
      [RFC7950].

A.1.2.  Example Usage

   The following example illustrates operational state data indicating
   the SSH encryption algorithms supported by the server:

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   <supported-algorithms
     xmlns="urn:ietf:params:xml:ns:yang:iana-ssh-encryption-algs"
     xmlns:sshea="urn:ietf:params:xml:ns:yang:iana-ssh-encryption-algs">
     <supported-algorithm>sshea:aes256-ctr</supported-algorithm>
     <supported-algorithm>sshea:aes256-cbc</supported-algorithm>
     <supported-algorithm>sshea:twofish256-cbc</supported-algorithm>
     <supported-algorithm>sshea:serpent256-cbc</supported-algorithm>
     <supported-algorithm>sshea:arcfour256</supported-algorithm>
     <supported-algorithm>sshea:serpent256-ctr</supported-algorithm>
     <supported-algorithm>sshea:aead-aes-256-gcm</supported-algorithm>
   </supported-algorithms>

A.1.3.  YANG Module

   Following are the complete contents to the initial IANA-maintained
   YANG module.  Please note that the date "2021-06-01" reflects the day
   on which the extraction occurred.

   <CODE BEGINS> file "iana-ssh-encryption-algs@2021-06-01.yang"

   module iana-ssh-encryption-algs {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:iana-ssh-encryption-algs";
     prefix sshea;

     organization
       "Internet Assigned Numbers Authority (IANA)";

     contact
       "Postal: ICANN
                12025 Waterfront Drive, Suite 300
                Los Angeles, CA  90094-2536
                United States of America
        Tel:    +1 310 301 5800
        Email:  iana@iana.org";

     description
       "This module defines identities for the encryption algorithms
        defined in the 'Encryption Algorithm Names' sub-registry of the
        'Secure Shell (SSH) Protocol Parameters' registry maintained
        by IANA.

        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

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        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).

        The initial version of this YANG module is part of RFC EEEE
        (https://www.rfc-editor.org/info/rfcEEEE); see the RFC
        itself for full legal notices.";

     revision 2021-06-01 {
       description
         "Initial version";
       reference
         "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
     }

     identity encryption-alg-base {
       description
         "Base identity used to identify encryption algorithms.";
     }

     identity triple-des-cbc { // YANG IDs cannot begin with a number
       base encryption-alg-base;
       description
         "3DES-CBC";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity blowfish-cbc {
       base encryption-alg-base;
       description
         "BLOWFISH-CBC";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity twofish256-cbc {
       base encryption-alg-base;
       description
         "TWOFISH256-CBC";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity twofish-cbc {

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       base encryption-alg-base;
       description
         "TWOFISH-CBC";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity twofish192-cbc {
       base encryption-alg-base;
       description
         "TWOFISH192-CBC";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity twofish128-cbc {
       base encryption-alg-base;
       description
         "TWOFISH128-CBC";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity aes256-cbc {
       base encryption-alg-base;
       description
         "AES256-CBC";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity aes192-cbc {
       base encryption-alg-base;
       description
         "AES192-CBC";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity aes128-cbc {
       base encryption-alg-base;
       description
         "AES128-CBC";

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       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity serpent256-cbc {
       base encryption-alg-base;
       description
         "SERPENT256-CBC";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity serpent192-cbc {
       base encryption-alg-base;
       description
         "SERPENT192-CBC";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity serpent128-cbc {
       base encryption-alg-base;
       description
         "SERPENT128-CBC";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity arcfour {
       base encryption-alg-base;
       status obsolete;
       description
         "ARCFOUR";
       reference
         "RFC 8758:
            Deprecating RC4 in Secure Shell (SSH)";
     }

     identity idea-cbc {
       base encryption-alg-base;
       description
         "IDEA-CBC";
       reference
         "RFC 4253:

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            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity cast128-cbc {
       base encryption-alg-base;
       description
         "CAST128-CBC";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity none {
       base encryption-alg-base;
       description
         "NONE";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity des-cbc {
       base encryption-alg-base;
       status obsolete;
       description
         "DES-CBC";
       reference
         "FIPS 46-3:
            Data Encryption Standard (DES)";
     }

     identity arcfour128 {
       base encryption-alg-base;
       status obsolete;
       description
         "ARCFOUR128";
       reference
         "RFC 8758:
            Deprecating RC4 in Secure Shell (SSH)";
     }

     identity arcfour256 {
       base encryption-alg-base;
       status obsolete;
       description
         "ARCFOUR256";
       reference
         "RFC 8758:

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            Deprecating RC4 in Secure Shell (SSH)";
     }

     identity aes128-ctr {
       base encryption-alg-base;
       description
         "AES128-CTR";
       reference
         "RFC 4344:
            The Secure Shell (SSH) Transport Layer Encryption Modes";
     }

     identity aes192-ctr {
       base encryption-alg-base;
       description
         "AES192-CTR";
       reference
         "RFC 4344:
            The Secure Shell (SSH) Transport Layer Encryption Modes";
     }

     identity aes256-ctr {
       base encryption-alg-base;
       description
         "AES256-CTR";
       reference
         "RFC 4344:
            The Secure Shell (SSH) Transport Layer Encryption Modes";
     }

     identity triple-des-ctr { // YANG IDs cannot begin with a number
       base encryption-alg-base;
       description
         "3DES-CTR";
       reference
         "RFC 4344:
            The Secure Shell (SSH) Transport Layer Encryption Modes";
     }

     identity blowfish-ctr {
       base encryption-alg-base;
       description
         "BLOWFISH-CTR";
       reference
         "RFC 4344:
            The Secure Shell (SSH) Transport Layer Encryption Modes";
     }

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     identity twofish128-ctr {
       base encryption-alg-base;
       description
         "TWOFISH128-CTR";
       reference
         "RFC 4344:
            The Secure Shell (SSH) Transport Layer Encryption Modes";
     }

     identity twofish192-ctr {
       base encryption-alg-base;
       description
         "TWOFISH192-CTR";
       reference
         "RFC 4344:
            The Secure Shell (SSH) Transport Layer Encryption Modes";
     }

     identity twofish256-ctr {
       base encryption-alg-base;
       description
         "TWOFISH256-CTR";
       reference
         "RFC 4344:
            The Secure Shell (SSH) Transport Layer Encryption Modes";
     }

     identity serpent128-ctr {
       base encryption-alg-base;
       description
         "SERPENT128-CTR";
       reference
         "RFC 4344:
            The Secure Shell (SSH) Transport Layer Encryption Modes";
     }

     identity serpent192-ctr {
       base encryption-alg-base;
       description
         "SERPENT192-CTR";
       reference
         "RFC 4344:
            The Secure Shell (SSH) Transport Layer Encryption Modes";
     }

     identity serpent256-ctr {
       base encryption-alg-base;
       description

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         "SERPENT256-CTR";
       reference
         "RFC 4344:
            The Secure Shell (SSH) Transport Layer Encryption Modes";
     }

     identity idea-ctr {
       base encryption-alg-base;
       description
         "IDEA-CTR";
       reference
         "RFC 4344:
            The Secure Shell (SSH) Transport Layer Encryption Modes";
     }

     identity cast128-ctr {
       base encryption-alg-base;
       description
         "CAST128-CTR";
       reference
         "RFC 4344:
            The Secure Shell (SSH) Transport Layer Encryption Modes";
     }

     identity aead-aes-128-gcm {
       base encryption-alg-base;
       description
         "AEAD_AES_128_GCM";
       reference
         "RFC 5647:
            AES Galois Counter Mode for the
            Secure Shell Transport Layer Protocol";
     }

     identity aead-aes-256-gcm {
       base encryption-alg-base;
       description
         "AEAD_AES_256_GCM";
       reference
         "RFC 5647:
            AES Galois Counter Mode for the
            Secure Shell Transport Layer Protocol";
     }

     // Protocol-accessible Nodes

     container supported-algorithms {
       config false;

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       description
         "A container for a list of encryption algorithms
          supported by the server.";
       leaf-list supported-algorithm {
         type identityref {
           base "sshea:encryption-alg-base";
         }
         description
           "A encryption algorithm supported by the server.";
       }
     }

   }

   <CODE ENDS>

A.2.  Initial Module for the "MAC Algorithm Names" Registry

A.2.1.  Data Model Overview

   This section provides an overview of the "iana-ssh-mac-algs" module
   in terms of its identities and protocol-accessible nodes.

A.2.1.1.  Identities

   The following diagram lists the base "identity" statements defined in
   the module, of which there is just one, and illustrates that all the
   derived identity statements are generated from the associated IANA-
   maintained registry [IANA-MAC-ALGS].

   Identities:
     +-- mac-alg-base
       +-- <identity-name from IANA registry>

      |  The diagram above uses syntax that is similar to but not
      |  defined in [RFC8340].

A.2.1.2.  Protocol-accessible Nodes

   The following tree diagram [RFC8340] lists all the protocol-
   accessible nodes defined in the "iana-ssh-mac-alg" module:

   module: iana-ssh-mac-algs
     +--ro supported-algorithms
        +--ro supported-algorithm*   identityref

   Comments:

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   *  Protocol-accessible nodes are those nodes that are accessible when
      the module is "implemented", as described in Section 5.6.5 of
      [RFC7950].

A.2.2.  Example Usage

   The following example illustrates operational state data indicating
   the SSH MAC algorithms supported by the server:

   <supported-algorithms
     xmlns="urn:ietf:params:xml:ns:yang:iana-ssh-mac-algs"
     xmlns:sshma="urn:ietf:params:xml:ns:yang:iana-ssh-mac-algs">
     <supported-algorithm>sshma:hmac-sha2-256</supported-algorithm>
     <supported-algorithm>sshma:hmac-sha2-512</supported-algorithm>
     <supported-algorithm>sshma:aead-aes-256-gcm</supported-algorithm>
   </supported-algorithms>

A.2.3.  YANG Module

   Following are the complete contents to the initial IANA-maintained
   YANG module.  Please note that the date "2021-06-01" reflects the day
   on which the extraction occurred.

   <CODE BEGINS> file "iana-ssh-mac-algs@2021-06-01.yang"

   module iana-ssh-mac-algs {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:iana-ssh-mac-algs";
     prefix sshma;

     organization
       "Internet Assigned Numbers Authority (IANA)";

     contact
       "Postal: ICANN
                12025 Waterfront Drive, Suite 300
                Los Angeles, CA  90094-2536
                United States of America
        Tel:    +1 310 301 5800
        Email:  iana@iana.org";

     description
       "This module defines identities for the MAC algorithms
        defined in the 'MAC Algorithm Names' sub-registry of the
        'Secure Shell (SSH) Protocol Parameters' registry maintained
        by IANA.

        Copyright (c) 2021 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 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).

        The initial version of this YANG module is part of RFC EEEE
        (https://www.rfc-editor.org/info/rfcEEEE); see the RFC
        itself for full legal notices.";

     revision 2021-06-01 {
       description
         "Initial version";
       reference
         "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
     }

     identity mac-alg-base {
       description
         "Base identity used to identify message authentication
          code (MAC) algorithms.";
     }

     identity hmac-sha1 {
       base mac-alg-base;
       description
         "HMAC-SHA1";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity hmac-sha1-96 {
       base mac-alg-base;
       description
         "HMAC-SHA1-96";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity hmac-md5 {
       base mac-alg-base;
       description
         "HMAC-MD5";

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       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity hmac-md5-96 {
       base mac-alg-base;
       description
         "HMAC-MD5-96";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity none {
       base mac-alg-base;
       description
         "NONE";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity aead-aes-128-gcm {
       base mac-alg-base;
       description
         "AEAD_AES_128_GCM";
       reference
         "RFC 5647:
            AES Galois Counter Mode for the
            Secure Shell Transport Layer Protocol";
     }

     identity aead-aes-256-gcm {
       base mac-alg-base;
       description
         "AEAD_AES_256_GCM";
       reference
         "RFC 5647:
            AES Galois Counter Mode for the
            Secure Shell Transport Layer Protocol";
     }

     identity hmac-sha2-256 {
       base mac-alg-base;
       description
         "HMAC-SHA2-256";
       reference

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         "RFC 6668:
            SHA-2 Data Integrity Verification for the
            Secure Shell (SSH) Transport Layer Protocol";
     }

     identity hmac-sha2-512 {
       base mac-alg-base;
       description
         "HMAC-SHA2-512";
       reference
         "RFC 6668:
            SHA-2 Data Integrity Verification for the
            Secure Shell (SSH) Transport Layer Protocol";
     }

     // Protocol-accessible Nodes

     container supported-algorithms {
       config false;
       description
         "A container for a list of MAC algorithms
          supported by the server.";
       leaf-list supported-algorithm {
         type identityref {
           base "sshma:mac-alg-base";
         }
         description
           "A MAC algorithm supported by the server.";
       }
     }

   }

   <CODE ENDS>

A.3.  Initial Module for the "Public Key Algorithm Names" Registry

A.3.1.  Data Model Overview

   This section provides an overview of the "iana-ssh-public-key-algs"
   module in terms of its identities and protocol-accessible nodes.

A.3.1.1.  Identities

   The following diagram lists the base "identity" statements defined in
   the module, of which there is just one, and illustrates that all the
   derived identity statements are generated from the associated IANA-
   maintained registry [IANA-PUBKEY-ALGS].

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   Identities:
     +-- public-key-alg-base
       +-- <identity-name from IANA registry>

      |  The diagram above uses syntax that is similar to but not
      |  defined in [RFC8340].

A.3.1.2.  Protocol-accessible Nodes

   The following tree diagram [RFC8340] lists all the protocol-
   accessible nodes defined in the "iana-ssh-public-key-alg" module:

   module: iana-ssh-public-key-algs
     +--ro supported-algorithms
        +--ro supported-algorithm*   identityref

   Comments:

   *  Protocol-accessible nodes are those nodes that are accessible when
      the module is "implemented", as described in Section 5.6.5 of
      [RFC7950].

A.3.2.  Example Usage

   The following example illustrates operational state data indicating
   the SSH public key algorithms supported by the server:

   =============== NOTE: '\' line wrapping per RFC 8792 ================

   <supported-algorithms
     xmlns="urn:ietf:params:xml:ns:yang:iana-ssh-public-key-algs"
     xmlns:sshpka="urn:ietf:params:xml:ns:yang:iana-ssh-public-key-algs\
   ">
     <supported-algorithm>sshpka:rsa-sha2-256</supported-algorithm>
     <supported-algorithm>sshpka:rsa-sha2-512</supported-algorithm>
     <supported-algorithm>sshpka:spki-sign-rsa</supported-algorithm>
     <supported-algorithm>sshpka:pgp-sign-dss</supported-algorithm>
     <supported-algorithm>sshpka:x509v3-rsa2048-sha256</supported-algor\
   ithm>
     <supported-algorithm>sshpka:ecdsa-sha2-nistp256</supported-algorit\
   hm>
     <supported-algorithm>sshpka:ecdsa-sha2-1.3.132.0.37</supported-alg\
   orithm>
     <supported-algorithm>sshpka:ssh-ed25519</supported-algorithm>
   </supported-algorithms>

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A.3.3.  YANG Module

   Following are the complete contents to the initial IANA-maintained
   YANG module.  Please note that the date "2021-06-01" reflects the day
   on which the extraction occurred.

   <CODE BEGINS> file "iana-ssh-public-key-algs@2021-06-01.yang"

   module iana-ssh-public-key-algs {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:iana-ssh-public-key-algs";
     prefix sshpka;

     organization
       "Internet Assigned Numbers Authority (IANA)";

     contact
       "Postal: ICANN
                12025 Waterfront Drive, Suite 300
                Los Angeles, CA  90094-2536
                United States of America
        Tel:    +1 310 301 5800
        Email:  iana@iana.org";

     description
       "This module defines identities for the public key algorithms
        defined in the 'Public Key Algorithm Names' sub-registry of the
        'Secure Shell (SSH) Protocol Parameters' registry maintained
        by IANA.

        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).

        The initial version of this YANG module is part of RFC EEEE
        (https://www.rfc-editor.org/info/rfcEEEE); see the RFC
        itself for full legal notices.";

     revision 2021-06-01 {
       description
         "Initial version";
       reference

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         "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
     }

     identity public-key-alg-base {
       description
         "Base identity used to identify public key algorithms.";
     }

     identity ssh-dss {
       base public-key-alg-base;
       description
         "SSH-DSS";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity ssh-rsa {
       base public-key-alg-base;
       description
         "SSH-RSA";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity rsa-sha2-256 {
       base public-key-alg-base;
       description
         "RSA-SHA2-256";
       reference
         "RFC 8332:
            Use of RSA Keys with SHA-256 and SHA-512
            in the Secure Shell (SSH) Protocol";
     }

     identity rsa-sha2-512 {
       base public-key-alg-base;
       description
         "RSA-SHA2-512";
       reference
         "RFC 8332:
            Use of RSA Keys with SHA-256 and SHA-512
            in the Secure Shell (SSH) Protocol";
     }

     identity spki-sign-rsa {
       base public-key-alg-base;

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       description
         "SPKI-SIGN-RSA";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity spki-sign-dss {
       base public-key-alg-base;
       description
         "SPKI-SIGN-DSS";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity pgp-sign-rsa {
       base public-key-alg-base;
       description
         "PGP-SIGN-RSA";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity pgp-sign-dss {
       base public-key-alg-base;
       description
         "PGP-SIGN-DSS";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity null {
       base public-key-alg-base;
       description
         "NULL";
       reference
         "RFC 4462:
            Generic Security Service Application Program Interface
            (GSS-API) Authentication and Key Exchange for the
            Secure Shell (SSH) Protocol";
     }

     identity ecdsa-sha2-nistp256 {
       base public-key-alg-base;
       description

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         "ECDSA-SHA2-NISTP256 (secp256r1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdsa-sha2-nistp384 {
       base public-key-alg-base;
       description
         "ECDSA-SHA2-NISTP384 (secp384r1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdsa-sha2-nistp521 {
       base public-key-alg-base;
       description
         "ECDSA-SHA2-NISTP521 (secp521r1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdsa-sha2-1.3.132.0.1 {
       base public-key-alg-base;
       description
         "ECDSA-SHA2-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdsa-sha2-1.2.840.10045.3.1.1 {
       base public-key-alg-base;
       description
         "ECDSA-SHA2-1.2.840.10045.3.1.1 (nistp192, secp192r1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdsa-sha2-1.3.132.0.33 {

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       base public-key-alg-base;
       description
         "ECDSA-SHA2-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdsa-sha2-1.3.132.0.26 {
       base public-key-alg-base;
       description
         "ECDSA-SHA2-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdsa-sha2-1.3.132.0.27 {
       base public-key-alg-base;
       description
         "ECDSA-SHA2-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdsa-sha2-1.3.132.0.16 {
       base public-key-alg-base;
       description
         "ECDSA-SHA2-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdsa-sha2-1.3.132.0.36 {
       base public-key-alg-base;
       description
         "ECDSA-SHA2-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

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     identity ecdsa-sha2-1.3.132.0.37 {
       base public-key-alg-base;
       description
         "ECDSA-SHA2-1.3.132.0.37 (nistb409, sect409r1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdsa-sha2-1.3.132.0.38 {
       base public-key-alg-base;
       description
         "ECDSA-SHA2-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity x509v3-ssh-dss {
       base public-key-alg-base;
       description
         "X509V3-SSH-DSS";
       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";
     }

     identity x509v3-ssh-rsa {
       base public-key-alg-base;
       description
         "X509V3-SSH-RSA";
       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";
     }

     identity x509v3-rsa2048-sha256 {
       base public-key-alg-base;
       description
         "X509V3-RSA2048-SHA256";
       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";
     }

     identity x509v3-ecdsa-sha2-nistp256 {

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       base public-key-alg-base;
       description
         "X509V3-ECDSA-SHA2-NISTP256 (secp256r1)";
       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";
     }

     identity x509v3-ecdsa-sha2-nistp384 {
       base public-key-alg-base;
       description
         "X509V3-ECDSA-SHA2-NISTP384 (secp384r1)";
       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";
     }

     identity x509v3-ecdsa-sha2-nistp521 {
       base public-key-alg-base;
       description
         "X509V3-ECDSA-SHA2-NISTP521 (secp521r1)";
       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";
     }

     identity x509v3-ecdsa-sha2-1.3.132.0.1 {
       base public-key-alg-base;
       description
         "X509V3-ECDSA-SHA2-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";
     }

     identity x509v3-ecdsa-sha2-1.2.840.10045.3.1.1 {
       base public-key-alg-base;
       description
         "X509V3-ECDSA-SHA2-1.2.840.10045.3.1.1 (nistp192, secp192r1)";
       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";
     }

     identity x509v3-ecdsa-sha2-1.3.132.0.33 {
       base public-key-alg-base;
       description
         "X509V3-ECDSA-SHA2-1.3.132.0.33 (nistp224, secp224r1)";

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       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";
     }

     identity x509v3-ecdsa-sha2-1.3.132.0.26 {
       base public-key-alg-base;
       description
         "X509V3-ECDSA-SHA2-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";
     }

     identity x509v3-ecdsa-sha2-1.3.132.0.27 {
       base public-key-alg-base;
       description
         "X509V3-ECDSA-SHA2-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";
     }

     identity x509v3-ecdsa-sha2-1.3.132.0.16 {
       base public-key-alg-base;
       description
         "X509V3-ECDSA-SHA2-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";
     }

     identity x509v3-ecdsa-sha2-1.3.132.0.36 {
       base public-key-alg-base;
       description
         "X509V3-ECDSA-SHA2-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";
     }

     identity x509v3-ecdsa-sha2-1.3.132.0.37 {
       base public-key-alg-base;
       description
         "X509V3-ECDSA-SHA2-1.3.132.0.37 (nistb409, sect409r1)";
       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";

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     }

     identity x509v3-ecdsa-sha2-1.3.132.0.38 {
       base public-key-alg-base;
       description
         "X509V3-ECDSA-SHA2-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 6187:
            X.509v3 Certificates for Secure Shell Authentication";
     }

     identity ssh-ed25519 {
       base public-key-alg-base;
       description
         "SSH-ED25519";
       reference
         "RFC 8709:
            Ed25519 and Ed448 Public Key Algorithms for the
            Secure Shell (SSH) Protocol";
     }

     identity ssh-ed448 {
       base public-key-alg-base;
       description
         "SSH-ED448";
       reference
         "RFC 8709:
            Ed25519 and Ed448 Public Key Algorithms for the
            Secure Shell (SSH) Protocol";
     }

     // Protocol-accessible Nodes

     container supported-algorithms {
       config false;
       description
         "A container for a list of public key algorithms
          supported by the server.";
       leaf-list supported-algorithm {
         type identityref {
           base "sshpka:public-key-alg-base";
         }
         description
           "A public key algorithm supported by the server.";
       }
     }

   }

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   <CODE ENDS>

A.4.  Initial Module for the "Key Exchange Method Names" Registry

A.4.1.  Data Model Overview

   This section provides an overview of the "iana-ssh-key-exchange-algs"
   module in terms of its identities and protocol-accessible nodes.

A.4.1.1.  Identities

   The following diagram lists the base "identity" statements defined in
   the module, of which there is just one, and illustrates that all the
   derived identity statements are generated from the associated IANA-
   maintained registry [IANA-KEYEX-ALGS].

   Identities:
     +-- key-exchange-alg-base
       +-- <identity-name from IANA registry>

      |  The diagram above uses syntax that is similar to but not
      |  defined in [RFC8340].

A.4.1.2.  Protocol-accessible Nodes

   The following tree diagram [RFC8340] lists all the protocol-
   accessible nodes defined in the "iana-ssh-key-exchange-alg" module:

   module: iana-ssh-key-exchange-algs
     +--ro supported-algorithms
        +--ro supported-algorithm*   identityref

   Comments:

   *  Protocol-accessible nodes are those nodes that are accessible when
      the module is "implemented", as described in Section 5.6.5 of
      [RFC7950].

A.4.2.  Example Usage

   The following example illustrates operational state data indicating
   the SSH key exchange algorithms supported by the server:

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   =============== NOTE: '\' line wrapping per RFC 8792 ================

   <supported-algorithms
     xmlns="urn:ietf:params:xml:ns:yang:iana-ssh-key-exchange-algs"
     xmlns:sshkea="urn:ietf:params:xml:ns:yang:iana-ssh-key-exchange-al\
   gs">
     <supported-algorithm>sshkea:diffie-hellman-group-exchange-sha256</\
   supported-algorithm>
     <supported-algorithm>sshkea:ecdh-sha2-nistp256</supported-algorith\
   m>
     <supported-algorithm>sshkea:rsa2048-sha256</supported-algorithm>
     <supported-algorithm>sshkea:gss-group1-sha1-curve25519-sha256</sup\
   ported-algorithm>
     <supported-algorithm>sshkea:gss-group14-sha1-nistp256</supported-a\
   lgorithm>
     <supported-algorithm>sshkea:gss-gex-sha1-nistp256</supported-algor\
   ithm>
     <supported-algorithm>sshkea:gss-group14-sha256-1.2.840.10045.3.1.1\
   </supported-algorithm>
     <supported-algorithm>sshkea:curve25519-sha256</supported-algorithm>
   </supported-algorithms>

A.4.3.  YANG Module

   Following are the complete contents to the initial IANA-maintained
   YANG module.  Please note that the date "2021-06-01" reflects the day
   on which the extraction occurred.

   <CODE BEGINS> file "iana-ssh-key-exchange-algs@2021-06-01.yang"

   module iana-ssh-key-exchange-algs {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:iana-ssh-key-exchange-algs";
     prefix sshkea;

     organization
       "Internet Assigned Numbers Authority (IANA)";

     contact
       "Postal: ICANN
                12025 Waterfront Drive, Suite 300
                Los Angeles, CA  90094-2536
                United States of America
        Tel:    +1 310 301 5800
        Email:  iana@iana.org";

     description
       "This module defines identities for the key exchange algorithms

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        defined in the 'Key Exchange Method Names' sub-registry of the
        'Secure Shell (SSH) Protocol Parameters' registry maintained
        by IANA.

        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).

        The initial version of this YANG module is part of RFC EEEE
        (https://www.rfc-editor.org/info/rfcEEEE); see the RFC
        itself for full legal notices.";

     revision 2021-06-01 {
       description
         "Initial version";
       reference
         "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
     }

     identity key-exchange-alg-base {
       description
         "Base identity used to identify key exchange algorithms.";
     }

     identity diffie-hellman-group-exchange-sha1 {
       base key-exchange-alg-base;
       description
         "DIFFIE-HELLMAN-GROUP-EXCHANGE-SHA1";
       reference
         "RFC 4419:
            Diffie-Hellman Group Exchange for the
            Secure Shell (SSH) Transport Layer Protocol";
     }

     identity diffie-hellman-group-exchange-sha256 {
       base key-exchange-alg-base;
       description
         "DIFFIE-HELLMAN-GROUP-EXCHANGE-SHA256";
       reference
         "RFC 4419:
            Diffie-Hellman Group Exchange for the
            Secure Shell (SSH) Transport Layer Protocol";

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     }

     identity diffie-hellman-group1-sha1 {
       base key-exchange-alg-base;
       description
         "DIFFIE-HELLMAN-GROUP1-SHA1";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity diffie-hellman-group14-sha1 {
       base key-exchange-alg-base;
       description
         "DIFFIE-HELLMAN-GROUP14-SHA1";
       reference
         "RFC 4253:
            The Secure Shell (SSH) Transport Layer Protocol";
     }

     identity diffie-hellman-group14-sha256 {
       base key-exchange-alg-base;
       description
         "DIFFIE-HELLMAN-GROUP14-SHA256";
       reference
         "RFC 8268:
            More Modular Exponentiation (MODP) Diffie-Hellman (DH)
            Key Exchange (KEX) Groups for Secure Shell (SSH)";
     }

     identity diffie-hellman-group15-sha512 {
       base key-exchange-alg-base;
       description
         "DIFFIE-HELLMAN-GROUP15-SHA512";
       reference
         "RFC 8268:
            More Modular Exponentiation (MODP) Diffie-Hellman (DH)
            Key Exchange (KEX) Groups for Secure Shell (SSH)";
     }

     identity diffie-hellman-group16-sha512 {
       base key-exchange-alg-base;
       description
         "DIFFIE-HELLMAN-GROUP16-SHA512";
       reference
         "RFC 8268:
            More Modular Exponentiation (MODP) Diffie-Hellman (DH)
            Key Exchange (KEX) Groups for Secure Shell (SSH)";

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     }

     identity diffie-hellman-group17-sha512 {
       base key-exchange-alg-base;
       description
         "DIFFIE-HELLMAN-GROUP17-SHA512";
       reference
         "RFC 8268:
            More Modular Exponentiation (MODP) Diffie-Hellman (DH)
            Key Exchange (KEX) Groups for Secure Shell (SSH)";
     }

     identity diffie-hellman-group18-sha512 {
       base key-exchange-alg-base;
       description
         "DIFFIE-HELLMAN-GROUP18-SHA512";
       reference
         "RFC 8268:
            More Modular Exponentiation (MODP) Diffie-Hellman (DH)
            Key Exchange (KEX) Groups for Secure Shell (SSH)";
     }

     identity ecdh-sha2-nistp256 {
       base key-exchange-alg-base;
       description
         "ECDH-SHA2-NISTP256 (secp256r1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdh-sha2-nistp384 {
       base key-exchange-alg-base;
       description
         "ECDH-SHA2-NISTP384 (secp384r1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdh-sha2-nistp521 {
       base key-exchange-alg-base;
       description
         "ECDH-SHA2-NISTP521 (secp521r1)";
       reference
         "RFC 5656:

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            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdh-sha2-1.3.132.0.1 {
       base key-exchange-alg-base;
       description
         "ECDH-SHA2-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdh-sha2-1.2.840.10045.3.1.1 {
       base key-exchange-alg-base;
       description
         "ECDH-SHA2-1.2.840.10045.3.1.1 (nistp192, secp192r1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdh-sha2-1.3.132.0.33 {
       base key-exchange-alg-base;
       description
         "ECDH-SHA2-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdh-sha2-1.3.132.0.26 {
       base key-exchange-alg-base;
       description
         "ECDH-SHA2-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdh-sha2-1.3.132.0.27 {
       base key-exchange-alg-base;
       description
         "ECDH-SHA2-1.3.132.0.27 (nistb233, sect233r1)";

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       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdh-sha2-1.3.132.0.16 {
       base key-exchange-alg-base;
       description
         "ECDH-SHA2-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdh-sha2-1.3.132.0.36 {
       base key-exchange-alg-base;
       description
         "ECDH-SHA2-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdh-sha2-1.3.132.0.37 {
       base key-exchange-alg-base;
       description
         "ECDH-SHA2-1.3.132.0.37 (nistb409, sect409r1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecdh-sha2-1.3.132.0.38 {
       base key-exchange-alg-base;
       description
         "ECDH-SHA2-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity ecmqv-sha2 {
       base key-exchange-alg-base;

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       description
         "ECMQV-SHA2";
       reference
         "RFC 5656:
            Elliptic Curve Algorithm Integration in the
            Secure Shell Transport Layer";
     }

     identity gss-group1-sha1-nistp256 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP1-SHA1-NISTP256 (secp256r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group1-sha1-nistp384 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP1-SHA1-NISTP384 (secp384r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group1-sha1-nistp521 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP1-SHA1-NISTP521 (secp521r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group1-sha1-1.3.132.0.1 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP1-SHA1-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 8732:

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            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group1-sha1-1.2.840.10045.3.1.1 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP1-SHA1-1.2.840.10045.3.1.1 (nistp192, secp192r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group1-sha1-1.3.132.0.33 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP1-SHA1-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group1-sha1-1.3.132.0.26 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP1-SHA1-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group1-sha1-1.3.132.0.27 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP1-SHA1-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

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     identity gss-group1-sha1-1.3.132.0.16 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP1-SHA1-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group1-sha1-1.3.132.0.36 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP1-SHA1-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group1-sha1-1.3.132.0.37 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP1-SHA1-1.3.132.0.37 (nistb409, sect409r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group1-sha1-1.3.132.0.38 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP1-SHA1-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group1-sha1-curve25519-sha256 {
       base key-exchange-alg-base;
       status deprecated;
       description

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         "GSS-GROUP1-SHA1-CURVE25519-SHA256";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group1-sha1-curve448-sha512 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP1-SHA1-CURVE448-SHA512";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha1-nistp256 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP14-SHA1-NISTP256 (secp256r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha1-nistp384 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP14-SHA1-NISTP384 (secp384r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha1-nistp521 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP14-SHA1-NISTP521 (secp521r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface

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            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha1-1.3.132.0.1 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP14-SHA1-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha1-1.2.840.10045.3.1.1 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP14-SHA1-1.2.840.10045.3.1.1 (nistp192, secp192r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha1-1.3.132.0.33 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP14-SHA1-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha1-1.3.132.0.26 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP14-SHA1-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha1-1.3.132.0.27 {

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       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP14-SHA1-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha1-1.3.132.0.16 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP14-SHA1-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha1-1.3.132.0.36 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP14-SHA1-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha1-1.3.132.0.37 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP14-SHA1-1.3.132.0.37 (nistb409, sect409r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha1-1.3.132.0.38 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP14-SHA1-1.3.132.0.38 (nistt571, sect571k1)";

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       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha1-curve25519-sha256 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP14-SHA1-CURVE25519-SHA256";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha1-curve448-sha512 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GROUP14-SHA1-CURVE448-SHA512";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-gex-sha1-nistp256 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GEX-SHA1-NISTP256 (secp256r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-gex-sha1-nistp384 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GEX-SHA1-NISTP384 (secp384r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";

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     }

     identity gss-gex-sha1-nistp521 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GEX-SHA1-NISTP521 (secp521r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-gex-sha1-1.3.132.0.1 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GEX-SHA1-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-gex-sha1-1.2.840.10045.3.1.1 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GEX-SHA1-1.2.840.10045.3.1.1 (nistp192, secp192r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-gex-sha1-1.3.132.0.33 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GEX-SHA1-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-gex-sha1-1.3.132.0.26 {
       base key-exchange-alg-base;

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       status deprecated;
       description
         "GSS-GEX-SHA1-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-gex-sha1-1.3.132.0.27 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GEX-SHA1-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-gex-sha1-1.3.132.0.16 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GEX-SHA1-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-gex-sha1-1.3.132.0.36 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GEX-SHA1-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-gex-sha1-1.3.132.0.37 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GEX-SHA1-1.3.132.0.37 (nistb409, sect409r1)";
       reference

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         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-gex-sha1-1.3.132.0.38 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GEX-SHA1-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-gex-sha1-curve25519-sha256 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GEX-SHA1-CURVE25519-SHA256";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-gex-sha1-curve448-sha512 {
       base key-exchange-alg-base;
       status deprecated;
       description
         "GSS-GEX-SHA1-CURVE448-SHA512";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity rsa1024-sha1 {
       base key-exchange-alg-base;
       description
         "RSA1024-SHA1";
       reference
         "RFC 4432:
            RSA Key Exchange for the Secure Shell (SSH)
            Transport Layer Protocol";
     }

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     identity rsa2048-sha256 {
       base key-exchange-alg-base;
       description
         "RSA2048-SHA256";
       reference
         "RFC 4432:
            RSA Key Exchange for the Secure Shell (SSH)
            Transport Layer Protocol";
     }

     identity ext-info-s {
       base key-exchange-alg-base;
       description
         "EXT-INFO-S";
       reference
         "RFC 8308:
            Extension Negotiation in the Secure Shell (SSH) Protocol";
     }

     identity ext-info-c {
       base key-exchange-alg-base;
       description
         "EXT-INFO-C";
       reference
         "RFC 8308:
            Extension Negotiation in the Secure Shell (SSH) Protocol";
     }

     identity gss-group14-sha256-nistp256 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP14-SHA256-NISTP256 (secp256r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha256-nistp384 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP14-SHA256-NISTP384 (secp384r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

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     identity gss-group14-sha256-nistp521 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP14-SHA256-NISTP521 (secp521r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha256-1.3.132.0.1 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP14-SHA256-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha256-1.2.840.10045.3.1.1 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP14-SHA256-1.2.840.10045.3.1.1 (nistp192, secp192r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha256-1.3.132.0.33 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP14-SHA256-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha256-1.3.132.0.26 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP14-SHA256-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";

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     }

     identity gss-group14-sha256-1.3.132.0.27 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP14-SHA256-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha256-1.3.132.0.16 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP14-SHA256-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha256-1.3.132.0.36 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP14-SHA256-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha256-1.3.132.0.37 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP14-SHA256-1.3.132.0.37 (nistb409, sect409r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha256-1.3.132.0.38 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP14-SHA256-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 8732:

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            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha256-curve25519-sha256 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP14-SHA256-CURVE25519-SHA256";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group14-sha256-curve448-sha512 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP14-SHA256-CURVE448-SHA512";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group15-sha512-nistp256 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP15-SHA512-NISTP256 (secp256r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group15-sha512-nistp384 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP15-SHA512-NISTP384 (secp384r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group15-sha512-nistp521 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP15-SHA512-NISTP521 (secp521r1)";

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       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group15-sha512-1.3.132.0.1 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP15-SHA512-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group15-sha512-1.2.840.10045.3.1.1 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP15-SHA512-1.2.840.10045.3.1.1 (nistp192, secp192r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group15-sha512-1.3.132.0.33 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP15-SHA512-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group15-sha512-1.3.132.0.26 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP15-SHA512-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group15-sha512-1.3.132.0.27 {
       base key-exchange-alg-base;

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       description
         "GSS-GROUP15-SHA512-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group15-sha512-1.3.132.0.16 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP15-SHA512-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group15-sha512-1.3.132.0.36 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP15-SHA512-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group15-sha512-1.3.132.0.37 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP15-SHA512-1.3.132.0.37 (nistb409, sect409r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group15-sha512-1.3.132.0.38 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP15-SHA512-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

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     identity gss-group15-sha512-curve25519-sha256 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP15-SHA512-CURVE25519-SHA256";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group15-sha512-curve448-sha512 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP15-SHA512-CURVE448-SHA512";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group16-sha512-nistp256 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP16-SHA512-NISTP256 (secp256r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group16-sha512-nistp384 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP16-SHA512-NISTP384 (secp384r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group16-sha512-nistp521 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP16-SHA512-NISTP521 (secp521r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";

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     }

     identity gss-group16-sha512-1.3.132.0.1 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP16-SHA512-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group16-sha512-1.2.840.10045.3.1.1 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP16-SHA512-1.2.840.10045.3.1.1 (nistp192, secp192r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group16-sha512-1.3.132.0.33 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP16-SHA512-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group16-sha512-1.3.132.0.26 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP16-SHA512-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group16-sha512-1.3.132.0.27 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP16-SHA512-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 8732:

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            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group16-sha512-1.3.132.0.16 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP16-SHA512-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group16-sha512-1.3.132.0.36 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP16-SHA512-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group16-sha512-1.3.132.0.37 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP16-SHA512-1.3.132.0.37 (nistb409, sect409r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group16-sha512-1.3.132.0.38 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP16-SHA512-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group16-sha512-curve25519-sha256 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP16-SHA512-CURVE25519-SHA256";

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       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group16-sha512-curve448-sha512 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP16-SHA512-CURVE448-SHA512";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group17-sha512-nistp256 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP17-SHA512-NISTP256 (secp256r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group17-sha512-nistp384 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP17-SHA512-NISTP384 (secp384r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group17-sha512-nistp521 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP17-SHA512-NISTP521 (secp521r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group17-sha512-1.3.132.0.1 {
       base key-exchange-alg-base;

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       description
         "GSS-GROUP17-SHA512-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group17-sha512-1.2.840.10045.3.1.1 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP17-SHA512-1.2.840.10045.3.1.1 (nistp192, secp192r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group17-sha512-1.3.132.0.33 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP17-SHA512-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group17-sha512-1.3.132.0.26 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP17-SHA512-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group17-sha512-1.3.132.0.27 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP17-SHA512-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

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     identity gss-group17-sha512-1.3.132.0.16 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP17-SHA512-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group17-sha512-1.3.132.0.36 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP17-SHA512-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group17-sha512-1.3.132.0.37 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP17-SHA512-1.3.132.0.37 (nistb409, sect409r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group17-sha512-1.3.132.0.38 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP17-SHA512-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group17-sha512-curve25519-sha256 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP17-SHA512-CURVE25519-SHA256";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";

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     }

     identity gss-group17-sha512-curve448-sha512 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP17-SHA512-CURVE448-SHA512";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group18-sha512-nistp256 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP18-SHA512-NISTP256 (secp256r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group18-sha512-nistp384 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP18-SHA512-NISTP384 (secp384r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group18-sha512-nistp521 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP18-SHA512-NISTP521 (secp521r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group18-sha512-1.3.132.0.1 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP18-SHA512-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 8732:

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            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group18-sha512-1.2.840.10045.3.1.1 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP18-SHA512-1.2.840.10045.3.1.1 (nistp192, secp192r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group18-sha512-1.3.132.0.33 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP18-SHA512-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group18-sha512-1.3.132.0.26 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP18-SHA512-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group18-sha512-1.3.132.0.27 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP18-SHA512-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group18-sha512-1.3.132.0.16 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP18-SHA512-1.3.132.0.16 (nistk283, sect283k1)";

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       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group18-sha512-1.3.132.0.36 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP18-SHA512-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group18-sha512-1.3.132.0.37 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP18-SHA512-1.3.132.0.37 (nistb409, sect409r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group18-sha512-1.3.132.0.38 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP18-SHA512-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group18-sha512-curve25519-sha256 {
       base key-exchange-alg-base;
       description
         "GSS-GROUP18-SHA512-CURVE25519-SHA256";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-group18-sha512-curve448-sha512 {
       base key-exchange-alg-base;

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       description
         "GSS-GROUP18-SHA512-CURVE448-SHA512";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp256-sha256-nistp256 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP256-SHA256-NISTP256 (secp256r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp256-sha256-nistp384 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP256-SHA256-NISTP384 (secp384r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp256-sha256-nistp521 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP256-SHA256-NISTP521 (secp521r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp256-sha256-1.3.132.0.1 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP256-SHA256-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

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     identity gss-nistp256-sha256-1.2.840.10045.3.1.1 {
       base key-exchange-alg-base;
       description
        "GSS-NISTP256-SHA256-1.2.840.10045.3.1.1 (nistp192, secp192r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp256-sha256-1.3.132.0.33 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP256-SHA256-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp256-sha256-1.3.132.0.26 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP256-SHA256-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp256-sha256-1.3.132.0.27 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP256-SHA256-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp256-sha256-1.3.132.0.16 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP256-SHA256-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";

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     }

     identity gss-nistp256-sha256-1.3.132.0.36 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP256-SHA256-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp256-sha256-1.3.132.0.37 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP256-SHA256-1.3.132.0.37 (nistb409, sect409r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp256-sha256-1.3.132.0.38 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP256-SHA256-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp256-sha256-curve25519-sha256 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP256-SHA256-CURVE25519-SHA256";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp256-sha256-curve448-sha512 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP256-SHA256-CURVE448-SHA512";
       reference
         "RFC 8732:

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            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp384-sha384-nistp256 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP384-SHA384-NISTP256 (secp256r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp384-sha384-nistp384 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP384-SHA384-NISTP384 (secp384r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp384-sha384-nistp521 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP384-SHA384-NISTP521 (secp521r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp384-sha384-1.3.132.0.1 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP384-SHA384-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp384-sha384-1.2.840.10045.3.1.1 {
       base key-exchange-alg-base;
       description
        "GSS-NISTP384-SHA384-1.2.840.10045.3.1.1 (nistp192, secp192r1)";

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       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp384-sha384-1.3.132.0.33 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP384-SHA384-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp384-sha384-1.3.132.0.26 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP384-SHA384-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp384-sha384-1.3.132.0.27 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP384-SHA384-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp384-sha384-1.3.132.0.16 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP384-SHA384-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp384-sha384-1.3.132.0.36 {
       base key-exchange-alg-base;

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       description
         "GSS-NISTP384-SHA384-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp384-sha384-1.3.132.0.37 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP384-SHA384-1.3.132.0.37 (nistb409, sect409r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp384-sha384-1.3.132.0.38 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP384-SHA384-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp384-sha384-curve25519-sha256 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP384-SHA384-CURVE25519-SHA256";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp384-sha384-curve448-sha512 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP384-SHA384-CURVE448-SHA512";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

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     identity gss-nistp521-sha512-nistp256 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP521-SHA512-NISTP256 (secp256r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp521-sha512-nistp384 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP521-SHA512-NISTP384 (secp384r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp521-sha512-nistp521 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP521-SHA512-NISTP521 (secp521r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp521-sha512-1.3.132.0.1 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP521-SHA512-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp521-sha512-1.2.840.10045.3.1.1 {
       base key-exchange-alg-base;
       description
        "GSS-NISTP521-SHA512-1.2.840.10045.3.1.1 (nistp192, secp192r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";

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     }

     identity gss-nistp521-sha512-1.3.132.0.33 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP521-SHA512-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp521-sha512-1.3.132.0.26 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP521-SHA512-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp521-sha512-1.3.132.0.27 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP521-SHA512-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp521-sha512-1.3.132.0.16 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP521-SHA512-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp521-sha512-1.3.132.0.36 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP521-SHA512-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 8732:

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            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp521-sha512-1.3.132.0.37 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP521-SHA512-1.3.132.0.37 (nistb409, sect409r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp521-sha512-1.3.132.0.38 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP521-SHA512-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp521-sha512-curve25519-sha256 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP521-SHA512-CURVE25519-SHA256";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-nistp521-sha512-curve448-sha512 {
       base key-exchange-alg-base;
       description
         "GSS-NISTP521-SHA512-CURVE448-SHA512";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve25519-sha256-nistp256 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE25519-SHA256-NISTP256 (secp256r1)";

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       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve25519-sha256-nistp384 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE25519-SHA256-NISTP384 (secp384r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve25519-sha256-nistp521 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE25519-SHA256-NISTP521 (secp521r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve25519-sha256-1.3.132.0.1 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE25519-SHA256-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve25519-sha256-1.2.840.10045.3.1.1 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE25519-SHA256-1.2.840.10045.3.1.1 (nistp192,
          secp192r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve25519-sha256-1.3.132.0.33 {

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       base key-exchange-alg-base;
       description
         "GSS-CURVE25519-SHA256-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve25519-sha256-1.3.132.0.26 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE25519-SHA256-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve25519-sha256-1.3.132.0.27 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE25519-SHA256-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve25519-sha256-1.3.132.0.16 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE25519-SHA256-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve25519-sha256-1.3.132.0.36 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE25519-SHA256-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

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     identity gss-curve25519-sha256-1.3.132.0.37 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE25519-SHA256-1.3.132.0.37 (nistb409, sect409r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve25519-sha256-1.3.132.0.38 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE25519-SHA256-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve25519-sha256-curve25519-sha256 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE25519-SHA256-CURVE25519-SHA256";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve25519-sha256-curve448-sha512 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE25519-SHA256-CURVE448-SHA512";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve448-sha512-nistp256 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE448-SHA512-NISTP256 (secp256r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";

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     }

     identity gss-curve448-sha512-nistp384 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE448-SHA512-NISTP384 (secp384r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve448-sha512-nistp521 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE448-SHA512-NISTP521 (secp521r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve448-sha512-1.3.132.0.1 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE448-SHA512-1.3.132.0.1 (nistk163, sect163k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve448-sha512-1.2.840.10045.3.1.1 {
       base key-exchange-alg-base;
       description
        "GSS-CURVE448-SHA512-1.2.840.10045.3.1.1 (nistp192, secp192r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve448-sha512-1.3.132.0.33 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE448-SHA512-1.3.132.0.33 (nistp224, secp224r1)";
       reference
         "RFC 8732:

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            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve448-sha512-1.3.132.0.26 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE448-SHA512-1.3.132.0.26 (nistk233, sect233k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve448-sha512-1.3.132.0.27 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE448-SHA512-1.3.132.0.27 (nistb233, sect233r1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve448-sha512-1.3.132.0.16 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE448-SHA512-1.3.132.0.16 (nistk283, sect283k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve448-sha512-1.3.132.0.36 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE448-SHA512-1.3.132.0.36 (nistk409, sect409k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve448-sha512-1.3.132.0.37 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE448-SHA512-1.3.132.0.37 (nistb409, sect409r1)";

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       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve448-sha512-1.3.132.0.38 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE448-SHA512-1.3.132.0.38 (nistt571, sect571k1)";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve448-sha512-curve25519-sha256 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE448-SHA512-CURVE25519-SHA256";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity gss-curve448-sha512-curve448-sha512 {
       base key-exchange-alg-base;
       description
         "GSS-CURVE448-SHA512-CURVE448-SHA512";
       reference
         "RFC 8732:
            Generic Security Service Application Program Interface
            (GSS-API) Key Exchange with SHA-2";
     }

     identity curve25519-sha256 {
       base key-exchange-alg-base;
       description
         "CURVE25519-SHA256";
       reference
         "RFC 8731:
            Secure Shell (SSH) Key Exchange Method
            Using Curve25519 and Curve448";
     }

     identity curve448-sha512 {
       base key-exchange-alg-base;

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       description
         "CURVE448-SHA512";
       reference
         "RFC 8731:
            Secure Shell (SSH) Key Exchange Method
            Using Curve25519 and Curve448";
     }

     // Protocol-accessible Nodes

     container supported-algorithms {
       config false;
       description
         "A container for a list of key exchange algorithms
          supported by the server.";
       leaf-list supported-algorithm {
         type identityref {
           base "sshkea:key-exchange-alg-base";
         }
         description
           "A key exchange algorithm supported by the server.";
       }
     }

   }

   <CODE ENDS>

Appendix B.  Change Log

   This section is to be removed before publishing as an RFC.

B.1.  00 to 01

   *  Noted that '0.0.0.0' and '::' might have special meanings.

   *  Renamed "keychain" to "keystore".

B.2.  01 to 02

   *  Removed the groupings 'listening-ssh-client-grouping' and
      'listening-ssh-server-grouping'.  Now modules only contain the
      transport-independent groupings.

   *  Simplified the "client-auth" part in the ietf-ssh-client module.
      It now inlines what it used to point to keystore for.

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   *  Added cipher suites for various algorithms into new 'ietf-ssh-
      common' module.

B.3.  02 to 03

   *  Removed 'RESTRICTED' enum from 'password' leaf type.

   *  Added a 'must' statement to container 'server-auth' asserting that
      at least one of the various auth mechanisms must be specified.

   *  Fixed description statement for leaf 'trusted-ca-certs'.

B.4.  03 to 04

   *  Change title to "YANG Groupings for SSH Clients and SSH Servers"

   *  Added reference to RFC 6668

   *  Added RFC 8174 to Requirements Language Section.

   *  Enhanced description statement for ietf-ssh-server's "trusted-ca-
      certs" leaf.

   *  Added mandatory true to ietf-ssh-client's "client-auth" 'choice'
      statement.

   *  Changed the YANG prefix for module ietf-ssh-common from 'sshcom'
      to 'sshcmn'.

   *  Removed the compression algorithms as they are not commonly
      configurable in vendors' implementations.

   *  Updating descriptions in transport-params-grouping and the
      servers's usage of it.

   *  Now tree diagrams reference ietf-netmod-yang-tree-diagrams

   *  Updated YANG to use typedefs around leafrefs to common keystore
      paths

   *  Now inlines key and certificates (no longer a leafref to keystore)

B.5.  04 to 05

   *  Merged changes from co-author.

B.6.  05 to 06

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   *  Updated to use trust anchors from trust-anchors draft (was
      keystore draft)

   *  Now uses new keystore grouping enabling asymmetric key to be
      either locally defined or a reference to the keystore.

B.7.  06 to 07

   *  factored the ssh-[client|server]-groupings into more reusable
      groupings.

   *  added if-feature statements for the new "ssh-host-keys" and
      "x509-certificates" features defined in draft-ietf-netconf-trust-
      anchors.

B.8.  07 to 08

   *  Added a number of compatibility matrices to Section 5 (thanks
      Frank!)

   *  Clarified that any configured "host-key-alg" values need to be
      compatible with the configured private key.

B.9.  08 to 09

   *  Updated examples to reflect update to groupings defined in the
      keystore -09 draft.

   *  Add SSH keepalives features and groupings.

   *  Prefixed top-level SSH grouping nodes with 'ssh-' and support
      mashups.

   *  Updated copyright date, boilerplate template, affiliation, and
      folding algorithm.

B.10.  09 to 10

   *  Reformatted the YANG modules.

B.11.  10 to 11

   *  Reformatted lines causing folding to occur.

B.12.  11 to 12

   *  Collapsed all the inner groupings into the top-level grouping.

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   *  Added a top-level "demux container" inside the top-level grouping.

   *  Added NACM statements and updated the Security Considerations
      section.

   *  Added "presence" statements on the "keepalive" containers, as was
      needed to address a validation error that appeared after adding
      the "must" statements into the NETCONF/RESTCONF client/server
      modules.

   *  Updated the boilerplate text in module-level "description"
      statement to match copyeditor convention.

B.13.  12 to 13

   *  Removed the "demux containers", floating the nacm:default-deny-
      write to each descendent node, and adding a note to model
      designers regarding the potential need to add their own demux
      containers.

   *  Fixed a couple references (section 2 --> section 3)

   *  In the server model, replaced <client-cert-auth> with <client-
      authentication> and introduced 'local-or-external' choice.

B.14.  13 to 14

   *  Updated to reflect changes in trust-anchors drafts (e.g., s/trust-
      anchors/truststore/g + s/pinned.//)

B.15.  14 to 15

   *  Updated examples to reflect ietf-crypto-types change (e.g.,
      identities --> enumerations)

   *  Updated "server-authentication" and "client-authentication" nodes
      from being a leaf of type "ts:host-keys-ref" or "ts:certificates-
      ref" to a container that uses "ts:local-or-truststore-host-keys-
      grouping" or "ts:local-or-truststore-certs-grouping".

B.16.  15 to 16

   *  Removed unnecessary if-feature statements in the -client and
      -server modules.

   *  Cleaned up some description statements in the -client and -server
      modules.

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   *  Fixed a canonical ordering issue in ietf-ssh-common detected by
      new pyang.

B.17.  16 to 17

   *  Removed choice local-or-external by removing the 'external' case
      and flattening the 'local' case and adding a "local-users-
      supported" feature.

   *  Updated examples to include the "*-key-format" nodes.

   *  Augmented-in "must" expressions ensuring that locally-defined
      public-key-format are "ct:ssh-public-key-format" (must expr for
      ref'ed keys are TBD).

B.18.  17 to 18

   *  Removed leaf-list 'other' from ietf-ssh-server.

   *  Removed unused 'external-client-auth-supported' feature.

   *  Added features client-auth-password, client-auth-hostbased, and
      client-auth-none.

   *  Renamed 'host-key' to 'public-key' for when refering to
      'publickey' based auth.

   *  Added new feature-protected 'hostbased' and 'none' to the 'user'
      node's config.

   *  Added new feature-protected 'hostbased' and 'none' to the 'client-
      identity' node's config.

   *  Updated examples to reflect new "bag" addition to truststore.

   *  Refined truststore/keystore groupings to ensure the key formats
      "must" be particular values.

   *  Switched to using truststore's new "public-key" bag (instead of
      separate "ssh-public-key" and "raw-public-key" bags.

   *  Updated client/server examples to cover ALL cases (local/ref x
      cert/raw-key/psk).

B.19.  18 to 19

   *  Updated the "keepalives" containers to address Michal Vasko's
      request to align with RFC 8071.

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   *  Removed algorithm-mapping tables from the "SSH Common Model"
      section

   *  Removed 'algorithm' node from examples.

   *  Added feature "userauth-publickey"

   *  Removed "choice auth-type", as auth-types are not exclusive.

   *  Renamed both "client-certs" and "server-certs" to "ee-certs"

   *  Switch "must" to assert the public-key-format is "subject-public-
      key-info-format" when certificates are used.

   *  Added a "Note to Reviewers" note to first page.

B.20.  19 to 20

   *  Added a "must 'public-key or password or hostbased or none or
      certificate'" statement to the "user" node in ietf-ssh-client

   *  Expanded "Data Model Overview section(s) [remove "wall" of tree
      diagrams].

   *  Moved the "ietf-ssh-common" module section to proceed the other
      two module sections.

   *  Updated the Security Considerations section.

B.21.  20 to 21

   *  Updated examples to reflect new "cleartext-" prefix in the crypto-
      types draft.

B.22.  21 to 22

   *  Cleaned up the SSH-client examples (i.e., removing FIXMEs)

   *  Fixed issues found by the SecDir review of the "keystore" draft.

   *  Updated the "ietf-ssh-client" module to use the new "password-
      grouping" grouping from the "crypto-types" module.

B.23.  22 to 23

   *  Addressed comments raised by YANG Doctor in the ct/ts/ks drafts.

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B.24.  23 to 24

   *  Removed the 'supported-authentication-methods' from {grouping ssh-
      server-grouping}/client-authentication.

   *  Added XML-comment above examples explaining the reason for the
      unexepected top-most element's presence.

   *  Added RFC-references to various 'feature' statements.

   *  Renamed "credentials" to "authentication methods"

   *  Renamed "client-auth-*" to "userauth-*"

   *  Renamed "client-identity-*" to "userauth-*"

   *  Fixed nits found by YANG Doctor reviews.

   *  Aligned modules with `pyang -f` formatting.

   *  Added a 'Contributors' section.

B.25.  24 to 25

   *  Renamed "{ietf-ssh-client}userauth-*" to "client-ident-*"

   *  Renamed "{ietf-ssh-server}userauth-*" to "local-user-auth-*"

   *  Moved algorithms in ietf-ssh-common (plus more) to IANA-maintained
      modules

   *  Added "config false" lists for algorithms supported by the server.

   *  Fixed issues found during YANG Doctor review.

Acknowledgements

   The authors would like to thank for following for lively discussions
   on list and in the halls (ordered by first name): Alan Luchuk, Andy
   Bierman, Balazs Kovacs, Benoit Claise, Bert Wijnen, David Lamparter,
   Gary Wu, Juergen Schoenwaelder, Ladislav Lhotka, Liang Xia, Martin
   Bjoerklund, Mehmet Ersue, Michal Vasko, Phil Shafer, Radek Krejci,
   Sean Turner, Tom Petch.

Contributors

   Special acknowledgement goes to Gary Wu for his work on the "ietf-
   ssh-common" module.

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Author's Address

   Kent Watsen
   Watsen Networks

   Email: kent+ietf@watsen.net

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