YANG Groupings for SSH Clients and SSH Servers

Internet-Draft	Groupings for SSH Clients and Servers	February 2024
Watsen	Expires 11 August 2024	[Page]

Abstract

This document defines seven YANG 1.1 modules. Three "IETF" modules, and four supporting "IANA" modules.¶

The three IETF modules are: ietf-ssh-common, ietf-ssh-client, and ietf-ssh-server. The "ietf-ssh-client" and "ietf-ssh-server" modules are the primary productions of this work, enabling the configuration and monitoring of SSH clients and servers.¶

The four IANA modules are: iana-ssh-encryption-algs, iana-ssh-key-exchange-algs, iana-ssh-mac-algs, and iana-ssh-public-key-algs. These modules each define YANG identities for an IANA-maintained algorithm registry.¶

Table 1: Label in Diagram to RFC Mapping
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]

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 permitted algorithms are in decreasing order of usage preference. The algorithm that appears first in the client list that also appears in the server list is the one that 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
  +-- asymmetric-key-pair-generation
  +-- algorithm-discovery

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:¶

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 following tree diagram [RFC8340] lists all the protocol-accessible nodes defined in the "ietf-ssh-common" module, without expanding the "grouping" statements:¶

module: ietf-ssh-common
  +--ro supported-algorithms {algorithm-discovery}?
     +--ro public-key-algorithms
     |  +--ro supported-algorithm*   sshpka:public-key-algorithm-ref
     +--ro encryption-algorithms
     |  +--ro supported-algorithm*   sshea:encryption-algorithm-ref
     +--ro key-exchange-algorithms
     |  +--ro supported-algorithm*
     |          sshkea:key-exchange-algorithm-ref
     +--ro mac-algorithms
        +--ro supported-algorithm*   sshma:mac-algorithm-ref

  rpcs:
    +---x generate-asymmetric-key-pair
            {asymmetric-key-pair-generation}?
       +---w input
       |  +---w algorithm
       |  |       sshpka:public-key-algorithm-ref
       |  +---w num-bits?               uint16
       |  +---w private-key-encoding
       |     +---w (private-key-encoding)
       |        +--:(cleartext) {ct:cleartext-private-keys}?
       |        |  +---w cleartext?   empty
       |        +--:(encrypted) {ct:encrypted-private-keys}?
       |        |  +---w encrypted
       |        |     +---w ks:encrypted-by-grouping
       |        +--:(hidden) {ct:hidden-private-keys}?
       |           +---w hidden?      empty
       +--ro output
          +---u ct:asymmetric-key-pair-grouping

Comments:¶

Protocol-accessible nodes are those nodes that are accessible when the module is "implemented", as described in Section 5.6.5 of [RFC7950].¶
The protocol-accessible nodes for the "ietf-ssh-common" module are limited to "supported-algorithms" container, which is constrained by the "algorithm-discovery" feature, and the RPC "generate-asymmetric-key-pair", which is constrained by the "asymmetric-key-pair-generation" feature.¶
The "encrypted-by-grouping" grouping is discussed in Section 2.1.3.1 of [I-D.ietf-netconf-keystore].¶
The "asymmetric-key-pair-grouping" grouping is discussed in Section 2.1.4.6 of [I-D.ietf-netconf-crypto-types].¶

2.2. Example Usage

The following example illustrates the "transport-params-grouping' grouping when populated with some data.¶

=============== 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</k\
ey-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>

The following example illustrates operational state data indicating the SSH algorithms supported by the server.¶

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

<supported-algorithms
  xmlns="urn:ietf:params:xml:ns:yang:ietf-ssh-common">
  <encryption-algorithms
    xmlns:sshea="urn:ietf:params:xml:ns:yang:iana-ssh-encryption-alg\
s">
    <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>
  </encryption-algorithms>
  <key-exchange-algorithms
    xmlns:sshkea="urn:ietf:params:xml:ns:yang:iana-ssh-key-exchange-\
algs">
    <supported-algorithm>sshkea:diffie-hellman-group-exchange-sha256\
</supported-algorithm>
    <supported-algorithm>sshkea:ecdh-sha2-nistp256</supported-algori\
thm>
    <supported-algorithm>sshkea:rsa2048-sha256</supported-algorithm>
    <supported-algorithm>sshkea:gss-group1-sha1-curve25519-sha256</s\
upported-algorithm>
    <supported-algorithm>sshkea:gss-group14-sha1-nistp256</supported\
-algorithm>
    <supported-algorithm>sshkea:gss-gex-sha1-nistp256</supported-alg\
orithm>
    <supported-algorithm>sshkea:gss-group14-sha256-1.2.840.10045.3.1\
.1</supported-algorithm>
    <supported-algorithm>sshkea:curve25519-sha256</supported-algorit\
hm>
  </key-exchange-algorithms>
  <mac-algorithms
    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>
  </mac-algorithms>
  <public-key-algorithms
    xmlns:sshpka="urn:ietf:params:xml:ns:yang:iana-ssh-public-key-al\
gs">
    <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-alg\
orithm>
    <supported-algorithm>sshpka:ecdsa-sha2-nistp256</supported-algor\
ithm>
    <supported-algorithm>sshpka:ecdsa-sha2-1.3.132.0.37</supported-a\
lgorithm>
    <supported-algorithm>sshpka:ssh-ed25519</supported-algorithm>
  </public-key-algorithms>
</supported-algorithms>

The following example illustrates the "generate-asymmetric-key-pair" RPC.¶

REQUEST¶

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

<rpc message-id="101"
  xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
  <generate-asymmetric-key-pair
    xmlns="urn:ietf:params:xml:ns:yang:ietf-ssh-common"
    xmlns:sshpka="urn:ietf:params:xml:ns:yang:iana-ssh-public-key-al\
gs">
    <algorithm>sshpka:ecdsa-sha2-nistp256</algorithm>
    <num-bits>521</num-bits>
    <private-key-encoding>
      <encrypted>
        <asymmetric-key-ref>hidden-asymmetric-key</asymmetric-key-re\
f>
      </encrypted>
    </private-key-encoding>
  </generate-asymmetric-key-pair>
</rpc>

RESPONSE¶

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

<rpc-reply message-id="101"
  xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"
  xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-crypto-types"
  xmlns:sshcmn="urn:ietf:params:xml:ns:yang:ietf-ssh-common">
  <sshcmn:public-key-format>ct:subject-public-key-info-format</sshcm\
n:public-key-format>
  <sshcmn:public-key>BASE64VALUE=</sshcmn:public-key>
  <sshcmn:private-key-format>ct:ec-private-key-format</sshcmn:privat\
e-key-format>
  <sshcmn:cleartext-private-key>BASE64VALUE=</sshcmn:cleartext-priva\
te-key>
</rpc-reply>

2.3. YANG Module

This YANG module has normative references to [RFC4253], [RFC4344], [RFC4419], [RFC5656], [RFC6187], [RFC6668], and [FIPS_186-6].¶

<CODE BEGINS> file "ietf-ssh-common@2024-02-08.yang"¶

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";
  }

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

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

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

  contact
    "WG Web:   https://datatracker.ietf.org/wg/netconf
     WG List:  NETCONF WG list <mailto:netconf@ietf.org>
     Author:   Kent Watsen <mailto:kent+ietf@watsen.net>
     Author:   Gary Wu <mailto:garywu@cisco.com>";

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

     Copyright (c) 2024 IETF Trust and the persons identified
     as authors of the code. All rights reserved.

     Redistribution and use in source and binary forms, with
     or without modification, is permitted pursuant to, and
     subject to the license terms contained in, the Revised
     BSD License set forth in Section 4.c of the IETF Trust's
     Legal Provisions Relating to IETF Documents
     (https://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC 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 2024-02-08 {
    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.";
  }

  feature asymmetric-key-pair-generation {
    description
      "Indicates that the server implements the
       'generate-asymmetric-key-pair' RPC.";
  }

  feature algorithm-discovery {
    description
      "Indicates that the server implements the
       'supported-algorithms' container.";
  }


  // 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 {
        type identityref {
          base sshpka:public-key-alg-base;
        }
        ordered-by user;
        description
          "Acceptable host key algorithms in order of decreasing
           preference.

           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 decreasing
           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 decreasing
           preference.

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

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

  // Protocol-accessible Nodes

  container supported-algorithms {
    if-feature "algorithm-discovery";
    config false;
    description
      "Identifies all of the supported algorithms.";
    container public-key-algorithms {
      description
        "A container for a list of public key algorithms
         supported by the server.";
      leaf-list supported-algorithm {
        type sshpka:public-key-algorithm-ref;
        description
          "A public key algorithm supported by the server.";
      }
    }
    container encryption-algorithms {
      description
        "A container for a list of encryption algorithms
         supported by the server.";
      leaf-list supported-algorithm {
        type sshea:encryption-algorithm-ref;
        description
          "An encryption algorithm supported by the server.";
      }
    }
    container key-exchange-algorithms {
      config false;
      description
        "A container for a list of key exchange algorithms
         supported by the server.";
      leaf-list supported-algorithm {
        type sshkea:key-exchange-algorithm-ref;
        description
          "A key exchange algorithm supported by the server.";
      }
    }
    container mac-algorithms {
      config false;
      description
        "A container for a list of MAC algorithms
         supported by the server.";
      leaf-list supported-algorithm {
        type sshma:mac-algorithm-ref;
        description
          "A MAC algorithm supported by the server.";
      }
    }
  }

  rpc generate-asymmetric-key-pair {
    if-feature "asymmetric-key-pair-generation";
    description
      "Requests the device to generate an public key using
       the specified key algorithm.";
    input {
      leaf algorithm {
        type sshpka:public-key-algorithm-ref;
        mandatory true;
        description
          "The algorithm to be used when generating the key.";
      }
      leaf num-bits {
        type uint16;
        description
          "Specifies the number of bits in the key to create.
           For RSA keys, the minimum size is 1024 bits and
           the default is 3072 bits. Generally, 3072 bits is
           considered sufficient. DSA keys must be exactly 1024
           bits as specified by FIPS 186-6.  For ECDSA keys, the
           'num-bits' value determines the key length by selecting
           from one of three elliptic curve sizes: 256, 384 or
           521 bits. Attempting to use bit lengths other than
           these three values for ECDSA keys will fail. ECDSA-SK,
           Ed25519 and Ed25519-SK keys have a fixed length and
           thus the 'num-bits' value is not specified.";
        reference
          "FIPS 186-6: Digital Signature Standard (DSS)";
      }
      container private-key-encoding {
        description
          "Indicates how the private key is to be encoded.";
        choice private-key-encoding {
          mandatory true;
          description
            "A choice amongst optional private key handling.";
          case cleartext {
            if-feature "ct:cleartext-private-keys";
            leaf cleartext {
              type empty;
              description
                "Indicates that the private key is to be returned
                 as a cleartext value.";
            }
          }
          case encrypted {
            if-feature "ct:encrypted-private-keys";
            container encrypted {
              description
                 "Indicates that the private key is to be encrypted
                  using the specified symmetric or asymmetric key.";
              uses ks:encrypted-by-grouping;
            }
          }
          case hidden {
            if-feature "ct:hidden-private-keys";
            leaf hidden {
              type empty;
              description
                "Indicates that the private key is to be hidden.

                 Unlike the 'cleartext' and 'encrypt' options, the
                 key returned is a placeholder for an internally
                 stored key.  See the 'Support for Built-in Keys'
                 section in RFC CCCC for information about hidden
                 keys.";
            }
          }
        }
      }
    }
    output {
      uses ct:asymmetric-key-pair-grouping;
    }
  } // end generate-asymmetric-key-pair

}

<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:¶

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:¶

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

  grouping ssh-client-grouping:
    +-- client-identity
    |  +-- username?      string
    |  +-- public-key! {client-ident-publickey}?
    |  |  +---u ks:inline-or-keystore-asymmetric-key-grouping
    |  +-- password! {client-ident-password}?
    |  |  +---u ct:password-grouping
    |  +-- hostbased! {client-ident-hostbased}?
    |  |  +---u ks:inline-or-keystore-asymmetric-key-grouping
    |  +-- none?          empty {client-ident-none}?
    |  +-- certificate! {sshcmn:ssh-x509-certs}?
    |     +---u ks:inline-or-keystore-end-entity-cert-with-key-group\
ing
    +-- server-authentication
    |  +-- ssh-host-keys!
    |  |  +---u ts:inline-or-truststore-public-keys-grouping
    |  +-- ca-certs! {sshcmn:ssh-x509-certs}?
    |  |  +---u ts:inline-or-truststore-certs-grouping
    |  +-- ee-certs! {sshcmn:ssh-x509-certs}?
    |     +---u ts:inline-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):¶
- The "inline-or-keystore-asymmetric-key-grouping" grouping is discussed in Section 2.1.3.4 of [I-D.ietf-netconf-keystore].¶
- The "inline-or-keystore-end-entity-cert-with-key-grouping" grouping is discussed in Section 2.1.3.6 of [I-D.ietf-netconf-keystore].¶
- The "inline-or-truststore-public-keys-grouping" grouping is discussed in Section 2.1.3.4 of [I-D.ietf-netconf-trust-anchors].¶
- The "inline-or-truststore-certs-grouping" grouping is discussed in Section 2.1.3.3 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. Thus this module, when implemented, does not itself define any 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 inlined key while the second uses a key configured in a keystore. Both examples are consistent with the examples presented in Section 2.2.1 of [I-D.ietf-netconf-trust-anchors] and Section 2.2.1 of [I-D.ietf-netconf-keystore].¶

The following configuration example uses inline-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">

  <!-- how this client will authenticate itself to the server -->
  <client-identity>
    <username>foobar</username>
    <public-key>
      <inline-definition>
        <private-key-format>ct:rsa-private-key-format</private-key-f\
ormat>
        <cleartext-private-key>BASE64VALUE=</cleartext-private-key>
      </inline-definition>
    </public-key>
  </client-identity>

  <!-- which host keys will this client trust -->
  <server-authentication>
    <ssh-host-keys>
      <inline-definition>
        <public-key>
          <name>corp-fw1</name>
          <public-key-format>ct:ssh-public-key-format</public-key-fo\
rmat>
          <public-key>BASE64VALUE=</public-key>
        </public-key>
        <public-key>
          <name>corp-fw2</name>
          <public-key-format>ct:ssh-public-key-format</public-key-fo\
rmat>
          <public-key>BASE64VALUE=</public-key>
        </public-key>
      </inline-definition>
    </ssh-host-keys>
    <ca-certs>
      <inline-definition>
        <certificate>
          <name>Server Cert Issuer #1</name>
          <cert-data>BASE64VALUE=</cert-data>
        </certificate>
        <certificate>
          <name>Server Cert Issuer #2</name>
          <cert-data>BASE64VALUE=</cert-data>
        </certificate>
      </inline-definition>
    </ca-certs>
    <ee-certs>
      <inline-definition>
        <certificate>
          <name>My Application #1</name>
          <cert-data>BASE64VALUE=</cert-data>
        </certificate>
        <certificate>
          <name>My Application #2</name>
          <cert-data>BASE64VALUE=</cert-data>
        </certificate>
      </inline-definition>
    </ee-certs>
  </server-authentication>

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

</ssh-client>

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

=============== 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>
    <public-key>
      <central-keystore-reference>ssh-rsa-key</central-keystore-refe\
rence>
    </public-key>
    <certificate>
      <central-keystore-reference>
        <asymmetric-key>ssh-rsa-key-with-cert</asymmetric-key>
        <certificate>ex-rsa-cert2</certificate>
      </central-keystore-reference>
    </certificate>
  </client-identity>

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

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

</ssh-client>

3.3. YANG Module

This YANG module has normative references to [RFC4252], [RFC4254], [RFC8341], [I-D.ietf-netconf-crypto-types], [I-D.ietf-netconf-trust-anchors], and [I-D.ietf-netconf-keystore].¶

<CODE BEGINS> file "ietf-ssh-client@2024-02-08.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;
    reference
      "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
  }

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

  contact
    "WG Web:   https://datatracker.ietf.org/wg/netconf
     WG List:  NETCONF WG list <mailto:netconf@ietf.org>
     Author:   Kent Watsen <mailto:kent+ietf@watsen.net>";

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

     Copyright (c) 2024 IETF Trust and the persons identified
     as authors of the code. All rights reserved.

     Redistribution and use in source and binary forms, with
     or without modification, is permitted pursuant to, and
     subject to the license terms contained in, the Revised
     BSD License set forth in Section 4.c of the IETF Trust's
     Legal Provisions Relating to IETF Documents
     (https://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC 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 2024-02-08 {
    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.
       The 'publickey' authentication type is required by
       RFC 4252, but common implementations allow 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.
       It is NOT RECOMMENDED to enable this feature.";
    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 nesting 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-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
           descendant 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:inline-or-keystore-asymmetric-key-grouping {
          refine "inline-or-keystore/inline/inline-definition" {
            must 'not(public-key-format) or derived-from-or-self'
               + '(public-key-format, "ct:ssh-public-key-format")';
          }
          refine "inline-or-keystore/central-keystore/"
               + "central-keystore-reference" {
            must 'not(deref(.)/../ks:public-key-format) or derived-'
               + 'from-or-self(deref(.)/../ks:public-key-format, '
               + '"ct: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
           descendant 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 descendant
           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:inline-or-keystore-asymmetric-key-grouping {
          refine "inline-or-keystore/inline/inline-definition" {
            must 'not(public-key-format) or derived-from-or-self('
               + 'public-key-format, "ct:ssh-public-key-format")';
          }
          refine "inline-or-keystore/central-keystore/"
               + "central-keystore-reference" {
            must 'not(deref(.)/../ks:public-key-format) or derived-'
               + 'from-or-self(deref(.)/../ks:public-key-format, '
               + '"ct: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:inline-or-keystore-end-entity-cert-with-key-grouping {
          refine "inline-or-keystore/inline/inline-definition" {
            must 'not(public-key-format) or derived-from-or-self('
               + 'public-key-format, "ct:subject-public-key-info-'
               + 'format")';
          }
          refine "inline-or-keystore/central-keystore/"
               + "central-keystore-reference/asymmetric-key" {
            must 'not(deref(.)/../ks:public-key-format) or derived-'
               + 'from-or-self(deref(.)/../ks:public-key-format, '
               + '"ct:subject-public-key-info-format")';
          }
        }
      }
    } // 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:inline-or-truststore-public-keys-grouping {
          refine
            "inline-or-truststore/inline/inline-definition/public"
            + "-key" {
            must 'derived-from-or-self(public-key-format,'
               + ' "ct:ssh-public-key-format")';
          }
          refine "inline-or-truststore/central-truststore/"
               + "central-truststore-reference" {
            must 'not(deref(.)/../ts:public-key/ts:public-key-'
               + 'format[not(derived-from-or-self(., "ct:ssh-'
               + 'public-key-format"))])';
          }
        }
      }
      container ca-certs {
        if-feature "sshcmn:ssh-x509-certs";
        presence
          "Indicates that the CA certificates have been configured.
           This statement is present so the mandatory descendant
           nodes do not imply that this node must be configured.";
        description
          "A set of 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:inline-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:inline-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 SSH
         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
         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
           SSH-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.¶

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:¶

=============== 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:inline-or-keystore-asymmetric-key-groupi\
ng
    |        +--:(certificate)
    |           +-- certificate {sshcmn:ssh-x509-certs}?
    |              +---u ks:inline-or-keystore-end-entity-cert-with-\
key-grouping
    +-- client-authentication
    |  +-- users {local-users-supported}?
    |  |  +-- user* [name]
    |  |     +-- name?          string
    |  |     +-- public-keys! {local-user-auth-publickey}?
    |  |     |  +---u ts:inline-or-truststore-public-keys-grouping
    |  |     +-- password
    |  |     |  +-- hashed-password?   ianach:crypt-hash
    |  |     |  |       {local-user-auth-password}?
    |  |     |  +--ro last-modified?     yang:date-and-time
    |  |     +-- hostbased! {local-user-auth-hostbased}?
    |  |     |  +---u ts:inline-or-truststore-public-keys-grouping
    |  |     +-- none?          empty {local-user-auth-none}?
    |  +-- ca-certs! {sshcmn:ssh-x509-certs}?
    |  |  +---u ts:inline-or-truststore-certs-grouping
    |  +-- ee-certs! {sshcmn:ssh-x509-certs}?
    |     +---u ts:inline-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.¶
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 "inline-or-keystore-asymmetric-key-grouping" grouping is discussed in Section 2.1.3.4 of [I-D.ietf-netconf-keystore].¶
- The "inline-or-keystore-end-entity-cert-with-key-grouping" grouping is discussed in Section 2.1.3.6 of [I-D.ietf-netconf-keystore].¶
- The "inline-or-truststore-public-keys-grouping" grouping is discussed in Section 2.1.3.4 of [I-D.ietf-netconf-trust-anchors].¶
- The "inline-or-truststore-certs-grouping" grouping is discussed in Section 2.1.3.3 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. Thus this module, when implemented, does not itself define any 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 inlined key while the second uses a key configured in a keystore. Both examples are consistent with the examples presented in Section 2.2.1 of [I-D.ietf-netconf-trust-anchors] and Section 2.2.1 of [I-D.ietf-netconf-keystore].¶

The following configuration example uses inline-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">

  <!-- the host-key this SSH server will present -->
  <server-identity>
    <host-key>
      <name>my-pubkey-based-host-key</name>
      <public-key>
        <inline-definition>
          <private-key-format>ct:rsa-private-key-format</private-key\
-format>
          <cleartext-private-key>BASE64VALUE=</cleartext-private-key>
        </inline-definition>
      </public-key>
    </host-key>
    <host-key>
      <name>my-cert-based-host-key</name>
      <certificate>
        <inline-definition>
          <private-key-format>ct:rsa-private-key-format</private-key\
-format>
          <cleartext-private-key>BASE64VALUE=</cleartext-private-key>
          <cert-data>BASE64VALUE=</cert-data>
        </inline-definition>
      </certificate>
    </host-key>
  </server-identity>

  <!-- the client credentials this SSH server will trust -->
  <client-authentication>
    <users>
      <user>
        <name>mary</name>
        <password>
          <hashed-password>$0$secret</hashed-password>
        </password>
        <public-keys>
          <inline-definition>
            <public-key>
              <name>Mary-Key-1</name>
              <public-key-format>ct:ssh-public-key-format</public-ke\
y-format>
              <public-key>BASE64VALUE=</public-key>
            </public-key>
            <public-key>
              <name>Mary-Key-2</name>
              <public-key-format>ct:ssh-public-key-format</public-ke\
y-format>
              <public-key>BASE64VALUE=</public-key>
            </public-key>
          </inline-definition>
        </public-keys>
      </user>
    </users>
    <ca-certs>
      <inline-definition>
        <certificate>
          <name>Identity Cert Issuer #1</name>
          <cert-data>BASE64VALUE=</cert-data>
        </certificate>
        <certificate>
          <name>Identity Cert Issuer #2</name>
          <cert-data>BASE64VALUE=</cert-data>
        </certificate>
      </inline-definition>
    </ca-certs>
    <ee-certs>
      <inline-definition>
        <certificate>
          <name>Application #1</name>
          <cert-data>BASE64VALUE=</cert-data>
        </certificate>
        <certificate>
          <name>Application #2</name>
          <cert-data>BASE64VALUE=</cert-data>
        </certificate>
      </inline-definition>
    </ee-certs>
  </client-authentication>

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

</ssh-server>

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

=============== 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">

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

  <!-- the client credentials this SSH server will trust -->
  <client-authentication>
    <users>
      <user>
        <name>mary</name>
        <password>
          <hashed-password>$0$secret</hashed-password>
        </password>
        <public-keys>
          <central-truststore-reference>SSH Public Keys for Applicat\
ion A</central-truststore-reference>
        </public-keys>
      </user>
    </users>
    <ca-certs>
      <central-truststore-reference>trusted-client-ca-certs</central\
-truststore-reference>
    </ca-certs>
    <ee-certs>
      <central-truststore-reference>trusted-client-ee-certs</central\
-truststore-reference>
    </ee-certs>
  </client-authentication>

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

</ssh-server>

4.3. YANG Module

This YANG module has references to [RFC4251], [RFC4252], [RFC4253], [RFC4254], [RFC7317], [RFC8341], [I-D.ietf-netconf-crypto-types], [I-D.ietf-netconf-trust-anchors], and [I-D.ietf-netconf-keystore].¶

<CODE BEGINS> file "ietf-ssh-server@2024-02-08.yang"¶

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

  import ietf-yang-types {
    prefix yang;
    reference
      "RFC 6991: Common YANG Data Types";
  }

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

  import ietf-ssh-common {
    prefix sshcmn;
    reference
      "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
  }

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

  contact
    "WG Web:   https://datatracker.ietf.org/wg/netconf
     WG List:  NETCONF WG list <mailto:netconf@ietf.org>
     Author:   Kent Watsen <mailto:kent+ietf@watsen.net>";

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

     Copyright (c) 2024 IETF Trust and the persons identified
     as authors of the code. All rights reserved.

     Redistribution and use in source and binary forms, with
     or without modification, is permitted pursuant to, and
     subject to the license terms contained in, the Revised
     BSD License set forth in Section 4.c of the IETF Trust's
     Legal Provisions Relating to IETF Documents
     (https://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC 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 2024-02-08 {
    description
      "Initial version";
    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 allow 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.";
    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 nesting 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 (see RFC 4251) 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
          "RFC 4251: The Secure Shell (SSH) Protocol Architecture
           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:inline-or-keystore-asymmetric-key-grouping {
              refine "inline-or-keystore/inline/inline-definition" {
                must 'not(public-key-format) or derived-from-or-self'
                 + '(public-key-format, "ct:ssh-public-key-format")';

              }
              refine "inline-or-keystore/central-keystore/"
                   + "central-keystore-reference" {
                must 'not(deref(.)/../ks:public-key-format) or '
                   + 'derived-from-or-self(deref(.)/../ks:public-'
                   + 'key-format, "ct: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:inline-or-keystore-end-entity-cert-with-key-grouping{
              refine "inline-or-keystore/inline/inline-definition" {
                must 'not(public-key-format) or derived-from-or-self'
                   + '(public-key-format, "ct:subject-public-key-'
                   + 'info-format")';
              }
              refine "inline-or-keystore/central-keystore/"
                   + "central-keystore-reference/asymmetric-key" {
                must 'not(deref(.)/../ks:public-key-format) or '
                   + 'derived-from-or-self(deref(.)/../ks:public-key'
                   + '-format, "ct:subject-public-key-info-format")';
              }
            }
          }
        }
      }
    } // container server-identity

    container client-authentication {
      nacm:default-deny-write;
      description
        "Specifies how the SSH server can be configured to
         authenticate SSH clients.  See RFC 4252 for a general
         discussion about SSH authentication.";
      reference
        "RFC 4252: The Secure Shell (SSH) Transport Layer";
      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.";
            reference
              "RFC 4253: The Secure Shell (SSH) Transport Layer
                         Protocol";
          }
          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
              "RFC BBBB: A YANG Data Model for a Truststore";
            uses ts:inline-or-truststore-public-keys-grouping {
              refine "inline-or-truststore/inline/inline-definition/"
                   + "public-key" {
                must 'derived-from-or-self(public-key-format,'
                   + ' "ct:ssh-public-key-format")';
              }
              refine "inline-or-truststore/central-truststore/"
                   + "central-truststore-reference" {
                must 'not(deref(.)/../ts:public-key/ts:public-key-'
                   + 'format[not(derived-from-or-self(., "ct:ssh-'
                   + 'public-key-format"))])';
              }
            }
          }
          container password {
            description
              "A password the SSH server may use to authenticate
               this user.  A user is authenticated if the hash
               of the supplied password matches this value.";
            leaf hashed-password {
              if-feature "local-user-auth-password";
              type ianach:crypt-hash;
              description
                "The password for this user.";
            }
            leaf last-modified {
              type yang:date-and-time;
              config false;
              description
                "Identifies when the password was last set.";
            }
          }
          container hostbased {
            if-feature "local-user-auth-hostbased";
            presence
              "Indicates that hostbased [RFC4252] 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 4252: The Secure Shell (SSH) Transport Layer
               RFC BBBB: A YANG Data Model for a Truststore";
            uses ts:inline-or-truststore-public-keys-grouping {
              refine "inline-or-truststore/inline/inline-definition/"
                   + "public-key" {
                must 'derived-from-or-self(public-key-format,'
                   + ' "ct:ssh-public-key-format")';
              }
              refine "inline-or-truststore/central-truststore/"
                   + "central-truststore-reference" {
                must 'not(deref(.)/../ts:public-key/ts:public-key-'
                   + 'format[not(derived-from-or-self(., "ct:ssh-'
                   + 'public-key-format"))])';
              }
            }
          }
          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.";
          }
        }
      } // users
      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:inline-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:inline-or-truststore-certs-grouping;
      }
    } // container client-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-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 SSH client.  An unresponsive SSH
         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 SSH client,
           a SSH-level message will be sent to test the
           aliveness of the SSH 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 SSH client before assuming the SSH client is
           no longer alive.";
      }
    }
  } // grouping ssh-server-grouping

}

<CODE ENDS>¶

Appendix A. YANG Modules for IANA

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

The modules contained in this section were generated by the following script. Run the script using the command `python gen-idenities.py`, to produce four YANG module files in the current directory.¶

<CODE BEGINS> file "gen-identities.py"¶

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

import re
import csv
import textwrap
import requests
import requests_cache
from io import StringIO
from datetime import datetime

# Metadata for the four YANG modules produced by this script
MODULES = [
    {
        "csv_url": "https://www.iana.org/assignments/ssh-parameters/\
ssh-parameters-17.csv",
        "spaced_name": "encryption",
        "hypenated_name": "encryption",
        "prefix": "sshea",
        "description": """    "This module defines identities for th\
e encryption algorithms
     defined in the 'Encryption Algorithm Names' sub-registry of the
     'Secure Shell (SSH) Protocol Parameters' registry maintained
     by IANA.""",
    },
    {
        "csv_url": "https://www.iana.org/assignments/ssh-parameters/\
ssh-parameters-19.csv",
        "spaced_name": "public key",
        "hypenated_name": "public-key",
        "prefix": "sshpka",
        "description": """    "This module defines identities for th\
e public key algorithms
     defined in the 'Public Key Algorithm Names' sub-registry of the
     'Secure Shell (SSH) Protocol Parameters' registry maintained
     by IANA."""
    },
    {
        "csv_url": "https://www.iana.org/assignments/ssh-parameters/\
ssh-parameters-18.csv",
        "spaced_name": "mac",
        "hypenated_name": "mac",
        "prefix": "sshma",
        "description": """    "This module defines identities for th\
e MAC algorithms
     defined in the 'MAC Algorithm Names' sub-registry of the
     'Secure Shell (SSH) Protocol Parameters' registry maintained
     by IANA."""
    },
    {
        "csv_url": "https://www.iana.org/assignments/ssh-parameters/\
ssh-parameters-16.csv",
        "spaced_name": "key exchange",
        "hypenated_name": "key-exchange",
        "prefix": "sshkea",
        "description": """    "This module defines identities for th\
e key exchange algorithms
     defined in the 'Key Exchange Method Names' sub-registry of the
     'Secure Shell (SSH) Protocol Parameters' registry maintained
     by IANA."""
    },
]




def create_module_begin(module, f):

    # Define template for all four modules
    PREAMBLE_TEMPLATE="""
module iana-ssh-HNAME-algs {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:iana-ssh-HNAME-algs";
  prefix PREFIX;

  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
DESCRIPTION

     Copyright (c) YEAR IETF Trust and the persons identified as
     authors of the code. All rights reserved.

     Redistribution and use in source and binary forms, with
     or without modification, is permitted pursuant to, and
     subject to the license terms contained in, the Revised
     BSD License set forth in Section 4.c of the IETF Trust's
     Legal Provisions Relating to IETF Documents
     (https://trustee.ietf.org/license-info).

     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 DATE {
    description
      "Reflects contents of the SNAME algorithms registry.";
    reference
      "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
  }

  // Typedefs

  typedef HNAME-algorithm-ref {
    type identityref {
      base "HNAME-alg-base";
    }
    description
      "A reference to an SSH SNAME algorithm identifier.";
  }


  // Identities

  identity HNAME-alg-base {
    description
      "Base identity for SSH SNAME algorithms.";
  }
"""
    # Replacements
    rep = {
      "DATE": datetime.today().strftime('%Y-%m-%d'),
      "YEAR": datetime.today().strftime('%Y'),
      "SNAME": module["spaced_name"],
      "HNAME": module["hypenated_name"],
      "PREFIX": module["prefix"],
      "DESCRIPTION": module["description"]
    }

    # Do the replacement
    rep = dict((re.escape(k), v) for k, v in rep.items())
    pattern = re.compile("|".join(rep.keys()))
    text = pattern.sub(lambda m: rep[re.escape(m.group(0))], PREAMBL\
E_TEMPLATE)

    # Write preamble into the file
    f.write(text)


def create_module_body(module, f):

    # Fetch the current CSV file from IANA
    r = requests.get(module["csv_url"])
    assert(r.status_code == 200)

    # Ascertain the first CSV column's name
    with StringIO(r.text) as csv_file:
        csv_reader = csv.reader(csv_file)
        for row in csv_reader:
            first_colname = row[0]
            break

    # Parse each CSV line
    with StringIO(r.text) as csv_file:
        csv_reader = csv.DictReader(csv_file)
        for row in csv_reader:

            # Extract just the ref
            refs = row["Reference"][1:-1]  # remove the '[' and ']' \
chars
            refs = refs.split("][")

            # There may be more than one ref
            titles = []
            for ref in refs:

                # Ascertain the ref's title
                if ref.startswith("RFC"):

                    # Fetch the current BIBTEX entry
                    bibtex_url="https://datatracker.ietf.org/doc/"+ \
ref.lower() + "/bibtex/"
                    r = requests.get(bibtex_url)
                    assert r.status_code == 200, "Could not GET " + \
bibtex_url

                    # Append to 'titles' value from the "title" line
                    for item in r.text.split("\n"):
                        if "title =" in item:
                            titles.append(re.sub('.*{{(.*)}}.*', r'\\
g<1>', item))
                            break
                    else:
                        raise Exception("RFC title not found")


                    # Insert a space: "RFCXXXX" --> "RFC XXXX"
                    index = refs.index(ref)
                    refs[index] = "RFC " + ref[3:]

                elif ref.startswith("FIPS"):
                    # Special case for FIPS, since no bibtex to fetch
                    if ref == "FIPS 46-3" or ref == "FIPS-46-3":
                        titles.append("Data Encryption Standard (DES\
)")
                    else:
                        raise Exception("FIPS ref not found")

                else:
                    raise Exception("ref not found")

            # Function used below
            def write_identity(alg):
                f.write('\n')
                if row[first_colname].startswith("3des"):
                    f.write(f'  identity {re.sub("3des", "triple-des\
", alg)} {{\n')
                else:
                    f.write(f'  identity {alg} {{\n')
                f.write(f'    base {module["hypenated_name"]}-alg-ba\
se;\n')
                if "HISTORIC" in row["Note"]:
                    f.write(f'    status obsolete;\n')
                elif "OK to Implement" in row:
                    if "MUST NOT" in row["OK to Implement"]:
                        f.write(f'    status obsolete;\n')
                    elif "SHOULD NOT" in row["OK to Implement"]:
                        f.write(f'    status deprecated;\n')
                f.write(f'    description\n')
                description = f'      "Identity for the \'{alg}\' al\
gorithm.'
                if "Section" in row["Note"]:
                    description += "  " + row["Note"]
                description += '";'
                description = textwrap.fill(description, width=69, s\
ubsequent_indent="       ")
                f.write(f'{description}\n')
                f.write('    reference\n')
                f.write('      "')
                if row["Reference"] == "":
                    f.write('Missing in IANA registry.')
                else:
                    ref_len = len(refs)
                    for i in range(ref_len):
                        ref = refs[i]
                        f.write(f'{ref}:\n')
                        title = "         " + titles[i]
                        title = textwrap.fill(title, width=69, subse\
quent_indent="         ")
                        f.write(f'{title}')
                        if i != ref_len - 1:
                            f.write('\n       ')
                f.write('";\n')
                f.write('  }\n')


            # Write one or more "identity" statements
            if not row[first_colname].endswith("-*"): # just one ide\
ntity
                # Avoid duplicate entries caused by the "ecdh-sha2-*\
" family expansion
                if not row[first_colname].startswith("ecdh-sha2-nist\
p"):
                    write_identity(row[first_colname])
            else: # a family of identities
                curve_ids = [
                    "nistp256",
                    "nistp384",
                    "nistp521",
                    "1.3.132.0.1",
                    "1.2.840.10045.3.1.1",
                    "1.3.132.0.33",
                    "1.3.132.0.26",
                    "1.3.132.0.27",
                    "1.3.132.0.16",
                    "1.3.132.0.36",
                    "1.3.132.0.37",
                    "1.3.132.0.38",
                ]
                for curve_id in curve_ids:
                    write_identity(row[first_colname][:-1] + curve_i\
d)


def create_module_end(f):

    # Install cache for 8x speedup
    requests_cache.install_cache()

    # Write module's closing brace
    f.write('\n}\n')


def create_module(module):

    # ascertain yang module's name
    yang_module_name = "iana-ssh-" + module["hypenated_name"] + "-al\
gs.yang"

    # create yang module file
    with open(yang_module_name, "w") as f:
        create_module_begin(module, f)
        create_module_body(module, f)
        create_module_end(f)


def main():
    for module in MODULES:
        create_module(module)


if __name__ == "__main__":
    main()

<CODE ENDS>¶

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

A.1.1. Data Model Overview

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

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. Typedefs

The following diagram illustrates the "typedef" statements defined in the "iana-ssh-encryption-algs" module:¶

Typedefs:
  identityref
    +-- encryption-algorithm-ref

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

Comments:¶

The typedef defined in the "iana-ssh-encryption-algs" module extends the "identityref" type defined in [RFC7950].¶

A.1.2. YANG Module

Following are the complete contents to the initial IANA-maintained YANG module. Please note that the date "2024-02-08" reflects the day on which the extraction occurred. Applications SHOULD use the IANA-maintained module, not the module defined in this draft.¶

This YANG module has normative references to [FIPS 46-3], [RFC4253], [RFC4344], [RFC5647], and [RFC8758].¶

<CODE BEGINS> file "iana-ssh-encryption-algs@2024-02-08.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) 2024 IETF Trust and the persons identified as
     authors of the code. All rights reserved.

     Redistribution and use in source and binary forms, with
     or without modification, is permitted pursuant to, and
     subject to the license terms contained in, the Revised
     BSD License set forth in Section 4.c of the IETF Trust's
     Legal Provisions Relating to IETF Documents
     (https://trustee.ietf.org/license-info).

     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 2024-02-08 {
    description
      "Reflects contents of the encryption algorithms registry.";
    reference
      "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
  }

  // Typedefs

  typedef encryption-algorithm-ref {
    type identityref {
      base "encryption-alg-base";
    }
    description
      "A reference to an SSH encryption algorithm identifier.";
  }


  // Identities

  identity encryption-alg-base {
    description
      "Base identity for SSH encryption algorithms.";
  }

  identity triple-des-cbc {
    base encryption-alg-base;
    description
      "Identity for the '3des-cbc' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity blowfish-cbc {
    base encryption-alg-base;
    description
      "Identity for the 'blowfish-cbc' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity twofish256-cbc {
    base encryption-alg-base;
    description
      "Identity for the 'twofish256-cbc' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity twofish-cbc {
    base encryption-alg-base;
    description
      "Identity for the 'twofish-cbc' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity twofish192-cbc {
    base encryption-alg-base;
    description
      "Identity for the 'twofish192-cbc' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity twofish128-cbc {
    base encryption-alg-base;
    description
      "Identity for the 'twofish128-cbc' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity aes256-cbc {
    base encryption-alg-base;
    description
      "Identity for the 'aes256-cbc' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity aes192-cbc {
    base encryption-alg-base;
    description
      "Identity for the 'aes192-cbc' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity aes128-cbc {
    base encryption-alg-base;
    description
      "Identity for the 'aes128-cbc' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity serpent256-cbc {
    base encryption-alg-base;
    description
      "Identity for the 'serpent256-cbc' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity serpent192-cbc {
    base encryption-alg-base;
    description
      "Identity for the 'serpent192-cbc' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity serpent128-cbc {
    base encryption-alg-base;
    description
      "Identity for the 'serpent128-cbc' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity arcfour {
    base encryption-alg-base;
    status obsolete;
    description
      "Identity for the 'arcfour' algorithm.";
    reference
      "RFC 8758:
         Deprecating RC4 in Secure Shell (SSH)";
  }

  identity idea-cbc {
    base encryption-alg-base;
    description
      "Identity for the 'idea-cbc' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity cast128-cbc {
    base encryption-alg-base;
    description
      "Identity for the 'cast128-cbc' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity none {
    base encryption-alg-base;
    description
      "Identity for the 'none' algorithm.  Section 6.3";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity des-cbc {
    base encryption-alg-base;
    status obsolete;
    description
      "Identity for the 'des-cbc' algorithm.";
    reference
      "FIPS-46-3:
         Data Encryption Standard (DES)";
  }

  identity arcfour128 {
    base encryption-alg-base;
    status obsolete;
    description
      "Identity for the 'arcfour128' algorithm.";
    reference
      "RFC 8758:
         Deprecating RC4 in Secure Shell (SSH)";
  }

  identity arcfour256 {
    base encryption-alg-base;
    status obsolete;
    description
      "Identity for the 'arcfour256' algorithm.";
    reference
      "RFC 8758:
         Deprecating RC4 in Secure Shell (SSH)";
  }

  identity aes128-ctr {
    base encryption-alg-base;
    description
      "Identity for the 'aes128-ctr' algorithm.";
    reference
      "RFC 4344:
         The Secure Shell (SSH) Transport Layer Encryption Modes";
  }

  identity aes192-ctr {
    base encryption-alg-base;
    description
      "Identity for the 'aes192-ctr' algorithm.";
    reference
      "RFC 4344:
         The Secure Shell (SSH) Transport Layer Encryption Modes";
  }

  identity aes256-ctr {
    base encryption-alg-base;
    description
      "Identity for the 'aes256-ctr' algorithm.";
    reference
      "RFC 4344:
         The Secure Shell (SSH) Transport Layer Encryption Modes";
  }

  identity triple-des-ctr {
    base encryption-alg-base;
    description
      "Identity for the '3des-ctr' algorithm.";
    reference
      "RFC 4344:
         The Secure Shell (SSH) Transport Layer Encryption Modes";
  }

  identity blowfish-ctr {
    base encryption-alg-base;
    description
      "Identity for the 'blowfish-ctr' algorithm.";
    reference
      "RFC 4344:
         The Secure Shell (SSH) Transport Layer Encryption Modes";
  }

  identity twofish128-ctr {
    base encryption-alg-base;
    description
      "Identity for the 'twofish128-ctr' algorithm.";
    reference
      "RFC 4344:
         The Secure Shell (SSH) Transport Layer Encryption Modes";
  }

  identity twofish192-ctr {
    base encryption-alg-base;
    description
      "Identity for the 'twofish192-ctr' algorithm.";
    reference
      "RFC 4344:
         The Secure Shell (SSH) Transport Layer Encryption Modes";
  }

  identity twofish256-ctr {
    base encryption-alg-base;
    description
      "Identity for the 'twofish256-ctr' algorithm.";
    reference
      "RFC 4344:
         The Secure Shell (SSH) Transport Layer Encryption Modes";
  }

  identity serpent128-ctr {
    base encryption-alg-base;
    description
      "Identity for the 'serpent128-ctr' algorithm.";
    reference
      "RFC 4344:
         The Secure Shell (SSH) Transport Layer Encryption Modes";
  }

  identity serpent192-ctr {
    base encryption-alg-base;
    description
      "Identity for the 'serpent192-ctr' algorithm.";
    reference
      "RFC 4344:
         The Secure Shell (SSH) Transport Layer Encryption Modes";
  }

  identity serpent256-ctr {
    base encryption-alg-base;
    description
      "Identity for the 'serpent256-ctr' algorithm.";
    reference
      "RFC 4344:
         The Secure Shell (SSH) Transport Layer Encryption Modes";
  }

  identity idea-ctr {
    base encryption-alg-base;
    description
      "Identity for the 'idea-ctr' algorithm.";
    reference
      "RFC 4344:
         The Secure Shell (SSH) Transport Layer Encryption Modes";
  }

  identity cast128-ctr {
    base encryption-alg-base;
    description
      "Identity for the 'cast128-ctr' algorithm.";
    reference
      "RFC 4344:
         The Secure Shell (SSH) Transport Layer Encryption Modes";
  }

  identity AEAD_AES_128_GCM {
    base encryption-alg-base;
    description
      "Identity for the 'AEAD_AES_128_GCM' algorithm.  Section 6.1";
    reference
      "RFC 5647:
         AES Galois Counter Mode for the Secure Shell Transport Layer
         Protocol";
  }

  identity AEAD_AES_256_GCM {
    base encryption-alg-base;
    description
      "Identity for the 'AEAD_AES_256_GCM' algorithm.  Section 6.2";
    reference
      "RFC 5647:
         AES Galois Counter Mode for the Secure Shell Transport Layer
         Protocol";
  }

}

<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 typedefs.¶

A.2.1.1. Identities

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. Typedefs

The following diagram illustrates the "typedef" statements defined in the "iana-ssh-mac-algs" module:¶

Typedefs:
  identityref
    +-- mac-algorithm-ref

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

Comments:¶

The typedef defined in the "iana-ssh-mac-algs" module extends the "identityref" type defined in [RFC7950].¶

A.2.2. YANG Module

This YANG module has normative references [RFC4253], [RFC5647], and [RFC6668].¶

<CODE BEGINS> file "iana-ssh-mac-algs@2024-02-08.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) 2024 IETF Trust and the persons identified as
     authors of the code. All rights reserved.

     Redistribution and use in source and binary forms, with
     or without modification, is permitted pursuant to, and
     subject to the license terms contained in, the Revised
     BSD License set forth in Section 4.c of the IETF Trust's
     Legal Provisions Relating to IETF Documents
     (https://trustee.ietf.org/license-info).

     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 2024-02-08 {
    description
      "Reflects contents of the mac algorithms registry.";
    reference
      "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
  }

  // Typedefs

  typedef mac-algorithm-ref {
    type identityref {
      base "mac-alg-base";
    }
    description
      "A reference to an SSH mac algorithm identifier.";
  }


  // Identities

  identity mac-alg-base {
    description
      "Base identity for SSH mac algorithms.";
  }

  identity hmac-sha1 {
    base mac-alg-base;
    description
      "Identity for the 'hmac-sha1' algorithm.  Section 6.4";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity hmac-sha1-96 {
    base mac-alg-base;
    description
      "Identity for the 'hmac-sha1-96' algorithm.  Section 6.4";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity hmac-md5 {
    base mac-alg-base;
    description
      "Identity for the 'hmac-md5' algorithm.  Section 6.4";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity hmac-md5-96 {
    base mac-alg-base;
    description
      "Identity for the 'hmac-md5-96' algorithm.  Section 6.4";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity none {
    base mac-alg-base;
    description
      "Identity for the 'none' algorithm.  Section 6.4";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity AEAD_AES_128_GCM {
    base mac-alg-base;
    description
      "Identity for the 'AEAD_AES_128_GCM' algorithm.  Section 6.1";
    reference
      "RFC 5647:
         AES Galois Counter Mode for the Secure Shell Transport Layer
         Protocol";
  }

  identity AEAD_AES_256_GCM {
    base mac-alg-base;
    description
      "Identity for the 'AEAD_AES_256_GCM' algorithm.  Section 6.2";
    reference
      "RFC 5647:
         AES Galois Counter Mode for the Secure Shell Transport Layer
         Protocol";
  }

  identity hmac-sha2-256 {
    base mac-alg-base;
    description
      "Identity for the 'hmac-sha2-256' algorithm.  Section 2";
    reference
      "RFC 6668:
         SHA-2 Data Integrity Verification for the Secure Shell (SSH)
         Transport Layer Protocol";
  }

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

}

<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 typedefs.¶

A.3.1.1. Identities

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. Typedefs

The following diagram illustrates the "typedef" statements defined in the "iana-ssh-public-key-algs" module:¶

Typedefs:
  identityref
    +-- public-key-algorithm-ref

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

Comments:¶

The typedef defined in the "iana-ssh-public-key-algs" module extends the "identityref" type defined in [RFC7950].¶

A.3.2. YANG Module

This YANG module has normative references [RFC4253], [RFC4462], [RFC5656], [RFC6187], [RFC8332], and [RFC8709].¶

<CODE BEGINS> file "iana-ssh-public-key-algs@2024-02-08.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) 2024 IETF Trust and the persons identified as
     authors of the code. All rights reserved.

     Redistribution and use in source and binary forms, with
     or without modification, is permitted pursuant to, and
     subject to the license terms contained in, the Revised
     BSD License set forth in Section 4.c of the IETF Trust's
     Legal Provisions Relating to IETF Documents
     (https://trustee.ietf.org/license-info).

     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 2024-02-08 {
    description
      "Reflects contents of the public key algorithms registry.";
    reference
      "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
  }

  // Typedefs

  typedef public-key-algorithm-ref {
    type identityref {
      base "public-key-alg-base";
    }
    description
      "A reference to an SSH public key algorithm identifier.";
  }


  // Identities

  identity public-key-alg-base {
    description
      "Base identity for SSH public key algorithms.";
  }

  identity ssh-dss {
    base public-key-alg-base;
    description
      "Identity for the 'ssh-dss' algorithm.  Section 6.6";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity ssh-rsa {
    base public-key-alg-base;
    description
      "Identity for the 'ssh-rsa' algorithm.  Section 6.6";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity rsa-sha2-256 {
    base public-key-alg-base;
    description
      "Identity for the 'rsa-sha2-256' algorithm.  Section 3";
    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
      "Identity for the 'rsa-sha2-512' algorithm.  Section 3";
    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;
    description
      "Identity for the 'spki-sign-rsa' algorithm.  Section 6.6";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity spki-sign-dss {
    base public-key-alg-base;
    description
      "Identity for the 'spki-sign-dss' algorithm.  Section 6.6";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity pgp-sign-rsa {
    base public-key-alg-base;
    description
      "Identity for the 'pgp-sign-rsa' algorithm.  Section 6.6";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity pgp-sign-dss {
    base public-key-alg-base;
    description
      "Identity for the 'pgp-sign-dss' algorithm.  Section 6.6";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity null {
    base public-key-alg-base;
    description
      "Identity for the 'null' algorithm.  Section 5";
    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
      "Identity for the 'ecdsa-sha2-nistp256' algorithm.";
    reference
      "RFC 5656:
         Elliptic Curve Algorithm Integration in the Secure Shell
         Transport Layer";
  }

  identity ecdsa-sha2-nistp384 {
    base public-key-alg-base;
    description
      "Identity for the 'ecdsa-sha2-nistp384' algorithm.";
    reference
      "RFC 5656:
         Elliptic Curve Algorithm Integration in the Secure Shell
         Transport Layer";
  }

  identity ecdsa-sha2-nistp521 {
    base public-key-alg-base;
    description
      "Identity for the 'ecdsa-sha2-nistp521' algorithm.";
    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
      "Identity for the 'ecdsa-sha2-1.3.132.0.1' algorithm.";
    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
      "Identity for the 'ecdsa-sha2-1.2.840.10045.3.1.1' algorithm.";
    reference
      "RFC 5656:
         Elliptic Curve Algorithm Integration in the Secure Shell
         Transport Layer";
  }

  identity ecdsa-sha2-1.3.132.0.33 {
    base public-key-alg-base;
    description
      "Identity for the 'ecdsa-sha2-1.3.132.0.33' algorithm.";
    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
      "Identity for the 'ecdsa-sha2-1.3.132.0.26' algorithm.";
    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
      "Identity for the 'ecdsa-sha2-1.3.132.0.27' algorithm.";
    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
      "Identity for the 'ecdsa-sha2-1.3.132.0.16' algorithm.";
    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
      "Identity for the 'ecdsa-sha2-1.3.132.0.36' algorithm.";
    reference
      "RFC 5656:
         Elliptic Curve Algorithm Integration in the Secure Shell
         Transport Layer";
  }

  identity ecdsa-sha2-1.3.132.0.37 {
    base public-key-alg-base;
    description
      "Identity for the 'ecdsa-sha2-1.3.132.0.37' algorithm.";
    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
      "Identity for the 'ecdsa-sha2-1.3.132.0.38' algorithm.";
    reference
      "RFC 5656:
         Elliptic Curve Algorithm Integration in the Secure Shell
         Transport Layer";
  }

  identity x509v3-ssh-dss {
    base public-key-alg-base;
    description
      "Identity for the 'x509v3-ssh-dss' algorithm.";
    reference
      "RFC 6187:
         X.509v3 Certificates for Secure Shell Authentication";
  }

  identity x509v3-ssh-rsa {
    base public-key-alg-base;
    description
      "Identity for the 'x509v3-ssh-rsa' algorithm.";
    reference
      "RFC 6187:
         X.509v3 Certificates for Secure Shell Authentication";
  }

  identity x509v3-rsa2048-sha256 {
    base public-key-alg-base;
    description
      "Identity for the 'x509v3-rsa2048-sha256' algorithm.";
    reference
      "RFC 6187:
         X.509v3 Certificates for Secure Shell Authentication";
  }

  identity x509v3-ecdsa-sha2-nistp256 {
    base public-key-alg-base;
    description
      "Identity for the 'x509v3-ecdsa-sha2-nistp256' algorithm.";
    reference
      "RFC 6187:
         X.509v3 Certificates for Secure Shell Authentication";
  }

  identity x509v3-ecdsa-sha2-nistp384 {
    base public-key-alg-base;
    description
      "Identity for the 'x509v3-ecdsa-sha2-nistp384' algorithm.";
    reference
      "RFC 6187:
         X.509v3 Certificates for Secure Shell Authentication";
  }

  identity x509v3-ecdsa-sha2-nistp521 {
    base public-key-alg-base;
    description
      "Identity for the 'x509v3-ecdsa-sha2-nistp521' algorithm.";
    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
      "Identity for the 'x509v3-ecdsa-sha2-1.3.132.0.1' algorithm.";
    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
      "Identity for the 'x509v3-ecdsa-sha2-1.2.840.10045.3.1.1'
       algorithm.";
    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
      "Identity for the 'x509v3-ecdsa-sha2-1.3.132.0.33' algorithm.";
    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
      "Identity for the 'x509v3-ecdsa-sha2-1.3.132.0.26' algorithm.";
    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
      "Identity for the 'x509v3-ecdsa-sha2-1.3.132.0.27' algorithm.";
    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
      "Identity for the 'x509v3-ecdsa-sha2-1.3.132.0.16' algorithm.";
    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
      "Identity for the 'x509v3-ecdsa-sha2-1.3.132.0.36' algorithm.";
    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
      "Identity for the 'x509v3-ecdsa-sha2-1.3.132.0.37' algorithm.";
    reference
      "RFC 6187:
         X.509v3 Certificates for Secure Shell Authentication";
  }

  identity x509v3-ecdsa-sha2-1.3.132.0.38 {
    base public-key-alg-base;
    description
      "Identity for the 'x509v3-ecdsa-sha2-1.3.132.0.38' algorithm.";
    reference
      "RFC 6187:
         X.509v3 Certificates for Secure Shell Authentication";
  }

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

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

}

<CODE ENDS>¶

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. Typedefs

The following diagram illustrates the "typedef" statements defined in the "iana-ssh-key-exchange-algs" module:¶

Typedefs:
  identityref
    +-- key-exchange-algorithm-ref

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

Comments:¶

The typedef defined in the "iana-ssh-key-exchange-algs" module extends the "identityref" type defined in [RFC7950].¶

A.4.2. YANG Module

This YANG module has normative references to [RFC4419], [RFC4432], [RFC5656], [RFC8268], [RFC8308], [RFC8731], [RFC8732].¶

<CODE BEGINS> file "iana-ssh-key-exchange-algs@2024-02-08.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
     defined in the 'Key Exchange Method Names' sub-registry of the
     'Secure Shell (SSH) Protocol Parameters' registry maintained
     by IANA.

     Copyright (c) 2024 IETF Trust and the persons identified as
     authors of the code. All rights reserved.

     Redistribution and use in source and binary forms, with
     or without modification, is permitted pursuant to, and
     subject to the license terms contained in, the Revised
     BSD License set forth in Section 4.c of the IETF Trust's
     Legal Provisions Relating to IETF Documents
     (https://trustee.ietf.org/license-info).

     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 2024-02-08 {
    description
      "Reflects contents of the key exchange algorithms registry.";
    reference
      "RFC EEEE: YANG Groupings for SSH Clients and SSH Servers";
  }

  // Typedefs

  typedef key-exchange-algorithm-ref {
    type identityref {
      base "key-exchange-alg-base";
    }
    description
      "A reference to an SSH key exchange algorithm identifier.";
  }


  // Identities

  identity key-exchange-alg-base {
    description
      "Base identity for SSH key exchange algorithms.";
  }

  identity diffie-hellman-group-exchange-sha1 {
    base key-exchange-alg-base;
    status deprecated;
    description
      "Identity for the 'diffie-hellman-group-exchange-sha1'
       algorithm.  Section 4.1";
    reference
      "RFC 4419:
         Diffie-Hellman Group Exchange for the Secure Shell (SSH)
         Transport Layer Protocol
       RFC 8270:
         Increase the Secure Shell Minimum Recommended Diffie-Hellman
         Modulus Size to 2048 Bits";
  }

  identity diffie-hellman-group-exchange-sha256 {
    base key-exchange-alg-base;
    description
      "Identity for the 'diffie-hellman-group-exchange-sha256'
       algorithm.  Section 4.2";
    reference
      "RFC 4419:
         Diffie-Hellman Group Exchange for the Secure Shell (SSH)
         Transport Layer Protocol
       RFC 8270:
         Increase the Secure Shell Minimum Recommended Diffie-Hellman
         Modulus Size to 2048 Bits";
  }

  identity diffie-hellman-group1-sha1 {
    base key-exchange-alg-base;
    status deprecated;
    description
      "Identity for the 'diffie-hellman-group1-sha1' algorithm.
       Section 8.1";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity diffie-hellman-group14-sha1 {
    base key-exchange-alg-base;
    description
      "Identity for the 'diffie-hellman-group14-sha1' algorithm.
       Section 8.2";
    reference
      "RFC 4253:
         The Secure Shell (SSH) Transport Layer Protocol";
  }

  identity diffie-hellman-group14-sha256 {
    base key-exchange-alg-base;
    description
      "Identity for the 'diffie-hellman-group14-sha256' algorithm.";
    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
      "Identity for the 'diffie-hellman-group15-sha512' algorithm.";
    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
      "Identity for the 'diffie-hellman-group16-sha512' algorithm.";
    reference
      "RFC 8268:
         More Modular Exponentiation (MODP) Diffie-Hellman (DH) Key
         Exchange (KEX) Groups for Secure Shell (SSH)";
  }

  identity diffie-hellman-group17-sha512 {
    base key-exchange-alg-base;
    description
      "Identity for the 'diffie-hellman-group17-sha512' algorithm.";
    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
      "Identity for the 'diffie-hellman-group18-sha512' algorithm.";
    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
      "Identity for the 'ecdh-sha2-nistp256' algorithm.";
    reference
      "RFC 5656:
         Elliptic Curve Algorithm Integration in the Secure Shell
         Transport Layer";
  }

  identity ecdh-sha2-nistp384 {
    base key-exchange-alg-base;
    description
      "Identity for the 'ecdh-sha2-nistp384' algorithm.";
    reference
      "RFC 5656:
         Elliptic Curve Algorithm Integration in the Secure Shell
         Transport Layer";
  }

  identity ecdh-sha2-nistp521 {
    base key-exchange-alg-base;
    description
      "Identity for the 'ecdh-sha2-nistp521' algorithm.";
    reference
      "RFC 5656:
         Elliptic Curve Algorithm Integration in the Secure Shell
         Transport Layer";
  }

  identity ecdh-sha2-1.3.132.0.1 {
    base key-exchange-alg-base;
    description
      "Identity for the 'ecdh-sha2-1.3.132.0.1' algorithm.";
    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
      "Identity for the 'ecdh-sha2-1.2.840.10045.3.1.1' algorithm.";
    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
      "Identity for the 'ecdh-sha2-1.3.132.0.33' algorithm.";
    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
      "Identity for the 'ecdh-sha2-1.3.132.0.26' algorithm.";
    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
      "Identity for the 'ecdh-sha2-1.3.132.0.27' algorithm.";
    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
      "Identity for the 'ecdh-sha2-1.3.132.0.16' algorithm.";
    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
      "Identity for the 'ecdh-sha2-1.3.132.0.36' algorithm.";
    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
      "Identity for the 'ecdh-sha2-1.3.132.0.37' algorithm.";
    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
      "Identity for the 'ecdh-sha2-1.3.132.0.38' algorithm.";
    reference
      "RFC 5656:
         Elliptic Curve Algorithm Integration in the Secure Shell
         Transport Layer";
  }

  identity ecmqv-sha2 {
    base key-exchange-alg-base;
    description
      "Identity for the 'ecmqv-sha2' algorithm.";
    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
      "Identity for the 'gss-group1-sha1-nistp256' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group1-sha1-nistp384' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group1-sha1-nistp521' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group1-sha1-1.3.132.0.1' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       RFC 8732:
         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
      "Identity for the 'gss-group1-sha1-1.2.840.10045.3.1.1'
       algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group1-sha1-1.3.132.0.33' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group1-sha1-1.3.132.0.26' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group1-sha1-1.3.132.0.27' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-group1-sha1-1.3.132.0.16 {
    base key-exchange-alg-base;
    status deprecated;
    description
      "Identity for the 'gss-group1-sha1-1.3.132.0.16' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group1-sha1-1.3.132.0.36' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group1-sha1-1.3.132.0.37' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group1-sha1-1.3.132.0.38' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group14-sha1-nistp256' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group14-sha1-nistp384' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group14-sha1-nistp521' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-group14-sha1-1.3.132.0.1 {
    base key-exchange-alg-base;
    status deprecated;
    description
      "Identity for the 'gss-group14-sha1-1.3.132.0.1' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group14-sha1-1.2.840.10045.3.1.1'
       algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group14-sha1-1.3.132.0.33' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group14-sha1-1.3.132.0.26' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-group14-sha1-1.3.132.0.27 {
    base key-exchange-alg-base;
    status deprecated;
    description
      "Identity for the 'gss-group14-sha1-1.3.132.0.27' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group14-sha1-1.3.132.0.16' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group14-sha1-1.3.132.0.36' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group14-sha1-1.3.132.0.37' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-group14-sha1-1.3.132.0.38' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-gex-sha1-nistp256' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-gex-sha1-nistp384' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-gex-sha1-nistp521 {
    base key-exchange-alg-base;
    status deprecated;
    description
      "Identity for the 'gss-gex-sha1-nistp521' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-gex-sha1-1.3.132.0.1' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-gex-sha1-1.2.840.10045.3.1.1'
       algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-gex-sha1-1.3.132.0.33' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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;
    status deprecated;
    description
      "Identity for the 'gss-gex-sha1-1.3.132.0.26' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-gex-sha1-1.3.132.0.27' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-gex-sha1-1.3.132.0.16' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-gex-sha1-1.3.132.0.36' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-gex-sha1-1.3.132.0.37' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       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
      "Identity for the 'gss-gex-sha1-1.3.132.0.38' algorithm.";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol
       RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss- {
    base key-exchange-alg-base;
    description
      "Identity for the 'gss-' algorithm.  Section 2.6";
    reference
      "RFC 4462:
         Generic Security Service Application Program Interface (GSS-
         API) Authentication and Key Exchange for the Secure Shell
         (SSH) Protocol";
  }

  identity rsa1024-sha1 {
    base key-exchange-alg-base;
    status obsolete;
    description
      "Identity for the 'rsa1024-sha1' algorithm.";
    reference
      "RFC 4432:
         RSA Key Exchange for the Secure Shell (SSH) Transport Layer
         Protocol";
  }

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

  identity ext-info-s {
    base key-exchange-alg-base;
    description
      "Identity for the 'ext-info-s' algorithm.  Section 2";
    reference
      "RFC 8308:
         Extension Negotiation in the Secure Shell (SSH) Protocol";
  }

  identity ext-info-c {
    base key-exchange-alg-base;
    description
      "Identity for the 'ext-info-c' algorithm.  Section 2";
    reference
      "RFC 8308:
         Extension Negotiation in the Secure Shell (SSH) Protocol";
  }

  identity gss-group14-sha256-nistp256 {
    base key-exchange-alg-base;
    description
      "Identity for the 'gss-group14-sha256-nistp256' algorithm.";
    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
      "Identity for the 'gss-group14-sha256-nistp384' algorithm.";
    reference
      "RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-group14-sha256-nistp521 {
    base key-exchange-alg-base;
    description
      "Identity for the 'gss-group14-sha256-nistp521' algorithm.";
    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
      "Identity for the 'gss-group14-sha256-1.3.132.0.1' algorithm.";
    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
      "Identity for the 'gss-group14-sha256-1.2.840.10045.3.1.1'
       algorithm.";
    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
      "Identity for the 'gss-group14-sha256-1.3.132.0.33'
       algorithm.";
    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
      "Identity for the 'gss-group14-sha256-1.3.132.0.26'
       algorithm.";
    reference
      "RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-group14-sha256-1.3.132.0.27 {
    base key-exchange-alg-base;
    description
      "Identity for the 'gss-group14-sha256-1.3.132.0.27'
       algorithm.";
    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
      "Identity for the 'gss-group14-sha256-1.3.132.0.16'
       algorithm.";
    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
      "Identity for the 'gss-group14-sha256-1.3.132.0.36'
       algorithm.";
    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
      "Identity for the 'gss-group14-sha256-1.3.132.0.37'
       algorithm.";
    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
      "Identity for the 'gss-group14-sha256-1.3.132.0.38'
       algorithm.";
    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
      "Identity for the 'gss-group15-sha512-nistp256' algorithm.";
    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
      "Identity for the 'gss-group15-sha512-nistp384' algorithm.";
    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
      "Identity for the 'gss-group15-sha512-nistp521' algorithm.";
    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
      "Identity for the 'gss-group15-sha512-1.3.132.0.1' algorithm.";
    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
      "Identity for the 'gss-group15-sha512-1.2.840.10045.3.1.1'
       algorithm.";
    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
      "Identity for the 'gss-group15-sha512-1.3.132.0.33'
       algorithm.";
    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
      "Identity for the 'gss-group15-sha512-1.3.132.0.26'
       algorithm.";
    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;
    description
      "Identity for the 'gss-group15-sha512-1.3.132.0.27'
       algorithm.";
    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
      "Identity for the 'gss-group15-sha512-1.3.132.0.16'
       algorithm.";
    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
      "Identity for the 'gss-group15-sha512-1.3.132.0.36'
       algorithm.";
    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
      "Identity for the 'gss-group15-sha512-1.3.132.0.37'
       algorithm.";
    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
      "Identity for the 'gss-group15-sha512-1.3.132.0.38'
       algorithm.";
    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
      "Identity for the 'gss-group16-sha512-nistp256' algorithm.";
    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
      "Identity for the 'gss-group16-sha512-nistp384' algorithm.";
    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
      "Identity for the 'gss-group16-sha512-nistp521' algorithm.";
    reference
      "RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-group16-sha512-1.3.132.0.1 {
    base key-exchange-alg-base;
    description
      "Identity for the 'gss-group16-sha512-1.3.132.0.1' algorithm.";
    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
      "Identity for the 'gss-group16-sha512-1.2.840.10045.3.1.1'
       algorithm.";
    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
      "Identity for the 'gss-group16-sha512-1.3.132.0.33'
       algorithm.";
    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
      "Identity for the 'gss-group16-sha512-1.3.132.0.26'
       algorithm.";
    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
      "Identity for the 'gss-group16-sha512-1.3.132.0.27'
       algorithm.";
    reference
      "RFC 8732:
         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
      "Identity for the 'gss-group16-sha512-1.3.132.0.16'
       algorithm.";
    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
      "Identity for the 'gss-group16-sha512-1.3.132.0.36'
       algorithm.";
    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
      "Identity for the 'gss-group16-sha512-1.3.132.0.37'
       algorithm.";
    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
      "Identity for the 'gss-group16-sha512-1.3.132.0.38'
       algorithm.";
    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
      "Identity for the 'gss-group17-sha512-nistp256' algorithm.";
    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
      "Identity for the 'gss-group17-sha512-nistp384' algorithm.";
    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
      "Identity for the 'gss-group17-sha512-nistp521' algorithm.";
    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;
    description
      "Identity for the 'gss-group17-sha512-1.3.132.0.1' algorithm.";
    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
      "Identity for the 'gss-group17-sha512-1.2.840.10045.3.1.1'
       algorithm.";
    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
      "Identity for the 'gss-group17-sha512-1.3.132.0.33'
       algorithm.";
    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
      "Identity for the 'gss-group17-sha512-1.3.132.0.26'
       algorithm.";
    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
      "Identity for the 'gss-group17-sha512-1.3.132.0.27'
       algorithm.";
    reference
      "RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-group17-sha512-1.3.132.0.16 {
    base key-exchange-alg-base;
    description
      "Identity for the 'gss-group17-sha512-1.3.132.0.16'
       algorithm.";
    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
      "Identity for the 'gss-group17-sha512-1.3.132.0.36'
       algorithm.";
    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
      "Identity for the 'gss-group17-sha512-1.3.132.0.37'
       algorithm.";
    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
      "Identity for the 'gss-group17-sha512-1.3.132.0.38'
       algorithm.";
    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
      "Identity for the 'gss-group18-sha512-nistp256' algorithm.";
    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
      "Identity for the 'gss-group18-sha512-nistp384' algorithm.";
    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
      "Identity for the 'gss-group18-sha512-nistp521' algorithm.";
    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
      "Identity for the 'gss-group18-sha512-1.3.132.0.1' algorithm.";
    reference
      "RFC 8732:
         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
      "Identity for the 'gss-group18-sha512-1.2.840.10045.3.1.1'
       algorithm.";
    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
      "Identity for the 'gss-group18-sha512-1.3.132.0.33'
       algorithm.";
    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
      "Identity for the 'gss-group18-sha512-1.3.132.0.26'
       algorithm.";
    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
      "Identity for the 'gss-group18-sha512-1.3.132.0.27'
       algorithm.";
    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
      "Identity for the 'gss-group18-sha512-1.3.132.0.16'
       algorithm.";
    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
      "Identity for the 'gss-group18-sha512-1.3.132.0.36'
       algorithm.";
    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
      "Identity for the 'gss-group18-sha512-1.3.132.0.37'
       algorithm.";
    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
      "Identity for the 'gss-group18-sha512-1.3.132.0.38'
       algorithm.";
    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
      "Identity for the 'gss-nistp256-sha256-nistp256' algorithm.";
    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
      "Identity for the 'gss-nistp256-sha256-nistp384' algorithm.";
    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
      "Identity for the 'gss-nistp256-sha256-nistp521' algorithm.";
    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
      "Identity for the 'gss-nistp256-sha256-1.3.132.0.1'
       algorithm.";
    reference
      "RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-nistp256-sha256-1.2.840.10045.3.1.1 {
    base key-exchange-alg-base;
    description
      "Identity for the 'gss-nistp256-sha256-1.2.840.10045.3.1.1'
       algorithm.";
    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
      "Identity for the 'gss-nistp256-sha256-1.3.132.0.33'
       algorithm.";
    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
      "Identity for the 'gss-nistp256-sha256-1.3.132.0.26'
       algorithm.";
    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
      "Identity for the 'gss-nistp256-sha256-1.3.132.0.27'
       algorithm.";
    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
      "Identity for the 'gss-nistp256-sha256-1.3.132.0.16'
       algorithm.";
    reference
      "RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-nistp256-sha256-1.3.132.0.36 {
    base key-exchange-alg-base;
    description
      "Identity for the 'gss-nistp256-sha256-1.3.132.0.36'
       algorithm.";
    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
      "Identity for the 'gss-nistp256-sha256-1.3.132.0.37'
       algorithm.";
    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
      "Identity for the 'gss-nistp256-sha256-1.3.132.0.38'
       algorithm.";
    reference
      "RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-nistp384-sha384-nistp256 {
    base key-exchange-alg-base;
    description
      "Identity for the 'gss-nistp384-sha384-nistp256' algorithm.";
    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
      "Identity for the 'gss-nistp384-sha384-nistp384' algorithm.";
    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
      "Identity for the 'gss-nistp384-sha384-nistp521' algorithm.";
    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
      "Identity for the 'gss-nistp384-sha384-1.3.132.0.1'
       algorithm.";
    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
      "Identity for the 'gss-nistp384-sha384-1.2.840.10045.3.1.1'
       algorithm.";
    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
      "Identity for the 'gss-nistp384-sha384-1.3.132.0.33'
       algorithm.";
    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
      "Identity for the 'gss-nistp384-sha384-1.3.132.0.26'
       algorithm.";
    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
      "Identity for the 'gss-nistp384-sha384-1.3.132.0.27'
       algorithm.";
    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
      "Identity for the 'gss-nistp384-sha384-1.3.132.0.16'
       algorithm.";
    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;
    description
      "Identity for the 'gss-nistp384-sha384-1.3.132.0.36'
       algorithm.";
    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
      "Identity for the 'gss-nistp384-sha384-1.3.132.0.37'
       algorithm.";
    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
      "Identity for the 'gss-nistp384-sha384-1.3.132.0.38'
       algorithm.";
    reference
      "RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-nistp521-sha512-nistp256 {
    base key-exchange-alg-base;
    description
      "Identity for the 'gss-nistp521-sha512-nistp256' algorithm.";
    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
      "Identity for the 'gss-nistp521-sha512-nistp384' algorithm.";
    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
      "Identity for the 'gss-nistp521-sha512-nistp521' algorithm.";
    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
      "Identity for the 'gss-nistp521-sha512-1.3.132.0.1'
       algorithm.";
    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
      "Identity for the 'gss-nistp521-sha512-1.2.840.10045.3.1.1'
       algorithm.";
    reference
      "RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-nistp521-sha512-1.3.132.0.33 {
    base key-exchange-alg-base;
    description
      "Identity for the 'gss-nistp521-sha512-1.3.132.0.33'
       algorithm.";
    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
      "Identity for the 'gss-nistp521-sha512-1.3.132.0.26'
       algorithm.";
    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
      "Identity for the 'gss-nistp521-sha512-1.3.132.0.27'
       algorithm.";
    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
      "Identity for the 'gss-nistp521-sha512-1.3.132.0.16'
       algorithm.";
    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
      "Identity for the 'gss-nistp521-sha512-1.3.132.0.36'
       algorithm.";
    reference
      "RFC 8732:
         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
      "Identity for the 'gss-nistp521-sha512-1.3.132.0.37'
       algorithm.";
    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
      "Identity for the 'gss-nistp521-sha512-1.3.132.0.38'
       algorithm.";
    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
      "Identity for the 'gss-curve25519-sha256-nistp256' algorithm.";
    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
      "Identity for the 'gss-curve25519-sha256-nistp384' algorithm.";
    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
      "Identity for the 'gss-curve25519-sha256-nistp521' algorithm.";
    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
      "Identity for the 'gss-curve25519-sha256-1.3.132.0.1'
       algorithm.";
    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
      "Identity for the 'gss-curve25519-sha256-1.2.840.10045.3.1.1'
       algorithm.";
    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 {
    base key-exchange-alg-base;
    description
      "Identity for the 'gss-curve25519-sha256-1.3.132.0.33'
       algorithm.";
    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
      "Identity for the 'gss-curve25519-sha256-1.3.132.0.26'
       algorithm.";
    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
      "Identity for the 'gss-curve25519-sha256-1.3.132.0.27'
       algorithm.";
    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
      "Identity for the 'gss-curve25519-sha256-1.3.132.0.16'
       algorithm.";
    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
      "Identity for the 'gss-curve25519-sha256-1.3.132.0.36'
       algorithm.";
    reference
      "RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-curve25519-sha256-1.3.132.0.37 {
    base key-exchange-alg-base;
    description
      "Identity for the 'gss-curve25519-sha256-1.3.132.0.37'
       algorithm.";
    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
      "Identity for the 'gss-curve25519-sha256-1.3.132.0.38'
       algorithm.";
    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
      "Identity for the 'gss-curve448-sha512-nistp256' algorithm.";
    reference
      "RFC 8732:
         Generic Security Service Application Program Interface (GSS-
         API) Key Exchange with SHA-2";
  }

  identity gss-curve448-sha512-nistp384 {
    base key-exchange-alg-base;
    description
      "Identity for the 'gss-curve448-sha512-nistp384' algorithm.";
    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
      "Identity for the 'gss-curve448-sha512-nistp521' algorithm.";
    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
      "Identity for the 'gss-curve448-sha512-1.3.132.0.1'
       algorithm.";
    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
      "Identity for the 'gss-curve448-sha512-1.2.840.10045.3.1.1'
       algorithm.";
    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
      "Identity for the 'gss-curve448-sha512-1.3.132.0.33'
       algorithm.";
    reference
      "RFC 8732:
         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
      "Identity for the 'gss-curve448-sha512-1.3.132.0.26'
       algorithm.";
    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
      "Identity for the 'gss-curve448-sha512-1.3.132.0.27'
       algorithm.";
    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
      "Identity for the 'gss-curve448-sha512-1.3.132.0.16'
       algorithm.";
    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
      "Identity for the 'gss-curve448-sha512-1.3.132.0.36'
       algorithm.";
    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
      "Identity for the 'gss-curve448-sha512-1.3.132.0.37'
       algorithm.";
    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
      "Identity for the 'gss-curve448-sha512-1.3.132.0.38'
       algorithm.";
    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
      "Identity for the 'curve25519-sha256' algorithm.";
    reference
      "RFC 8731:
         Secure Shell (SSH) Key Exchange Method Using Curve25519 and
         Curve448";
  }

  identity curve448-sha512 {
    base key-exchange-alg-base;
    description
      "Identity for the 'curve448-sha512' algorithm.";
    reference
      "RFC 8731:
         Secure Shell (SSH) Key Exchange Method Using Curve25519 and
         Curve448";
  }

}

<CODE ENDS>¶