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Versions: (draft-kwatsen-netconf-crypto-types) 00 01 02 03 04 05 06 07 08 09 10 11 12

NETCONF Working Group                                          K. Watsen
Internet-Draft                                           Watsen Networks
Intended status: Standards Track                                 H. Wang
Expires: May 4, 2020                                              Huawei
                                                        November 1, 2019


                Common YANG Data Types for Cryptography
                   draft-ietf-netconf-crypto-types-12

Abstract

   This document defines four YANG modules for types useful to
   cryptographic applications.  The modules defined include:

   o  ietf-crypto-types

   o  iana-symmetric-algs

   o  iana-asymmetric-algs

   o  iana-hash-algs

Editorial Note (To be removed by RFC Editor)

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

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

   o  "XXXX" --> the assigned RFC value for this draft

   Artwork in this document contains placeholder values for the date of
   publication of this draft.  Please apply the following replacement:

   o  "2019-11-02" --> the publication date of this draft

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

   o  Appendix B.  Change Log








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Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on May 4, 2020.

Copyright Notice

   Copyright (c) 2019 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  The Crypto Types Module . . . . . . . . . . . . . . . . . . .   4
     2.1.  Tree Diagram  . . . . . . . . . . . . . . . . . . . . . .   4
     2.2.  YANG Module . . . . . . . . . . . . . . . . . . . . . . .   6
     2.3.  Examples  . . . . . . . . . . . . . . . . . . . . . . . .  23
   3.  The Symmetric Algorithms Module . . . . . . . . . . . . . . .  27
     3.1.  Tree Diagram  . . . . . . . . . . . . . . . . . . . . . .  27
     3.2.  YANG Module . . . . . . . . . . . . . . . . . . . . . . .  27
     3.3.  Examples  . . . . . . . . . . . . . . . . . . . . . . . .  31
   4.  The Asymmetric Algorithms Module  . . . . . . . . . . . . . .  31
     4.1.  Tree Diagram  . . . . . . . . . . . . . . . . . . . . . .  31
     4.2.  YANG Module . . . . . . . . . . . . . . . . . . . . . . .  32
     4.3.  Examples  . . . . . . . . . . . . . . . . . . . . . . . .  36
   5.  The Hash Algorithms Module  . . . . . . . . . . . . . . . . .  36



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     5.1.  Tree Diagram  . . . . . . . . . . . . . . . . . . . . . .  36
     5.2.  YANG Module . . . . . . . . . . . . . . . . . . . . . . .  36
     5.3.  Examples  . . . . . . . . . . . . . . . . . . . . . . . .  40
   6.  Security Considerations . . . . . . . . . . . . . . . . . . .  40
     6.1.  Support for Algorithms  . . . . . . . . . . . . . . . . .  40
     6.2.  No Support for CRMF . . . . . . . . . . . . . . . . . . .  41
     6.3.  Access to Data Nodes  . . . . . . . . . . . . . . . . . .  41
   7.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  42
     7.1.  The IETF XML Registry . . . . . . . . . . . . . . . . . .  42
     7.2.  The YANG Module Names Registry  . . . . . . . . . . . . .  43
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  43
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  43
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  46
   Appendix A.  Change Log . . . . . . . . . . . . . . . . . . . . .  49
     A.1.  I-D to 00 . . . . . . . . . . . . . . . . . . . . . . . .  49
     A.2.  00 to 01  . . . . . . . . . . . . . . . . . . . . . . . .  49
     A.3.  01 to 02  . . . . . . . . . . . . . . . . . . . . . . . .  49
     A.4.  02 to 03  . . . . . . . . . . . . . . . . . . . . . . . .  49
     A.5.  03 to 04  . . . . . . . . . . . . . . . . . . . . . . . .  50
     A.6.  04 to 05  . . . . . . . . . . . . . . . . . . . . . . . .  50
     A.7.  05 to 06  . . . . . . . . . . . . . . . . . . . . . . . .  50
     A.8.  06 to 07  . . . . . . . . . . . . . . . . . . . . . . . .  51
     A.9.  07 to 08  . . . . . . . . . . . . . . . . . . . . . . . .  51
     A.10. 08 to 09  . . . . . . . . . . . . . . . . . . . . . . . .  51
     A.11. 09 to 10  . . . . . . . . . . . . . . . . . . . . . . . .  51
     A.12. 10 to 11  . . . . . . . . . . . . . . . . . . . . . . . .  52
     A.13. 11 to 12  . . . . . . . . . . . . . . . . . . . . . . . .  52
   Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . .  52
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  52

1.  Introduction

   This document defines four YANG 1.1 [RFC7950] modules for types
   useful to cryptographic applications.  The modules defined include:

   o  ietf-crypto-types

   o  iana-symmetric-algs

   o  iana-asymmetric-algs

   o  iana-hash-algs

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and
   "OPTIONAL" in this document are to be interpreted as described in BCP
   14 [RFC2119] [RFC8174] when, and only when, they appear in all
   capitals, as shown here.



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2.  The Crypto Types Module

2.1.  Tree Diagram

   This section provides a tree diagram [RFC8340] for the "ietf-crypto-
   types" module.  Only "grouping" statements are represented, as tree
   diagrams have no means to represent identities or typedefs.

   module: ietf-crypto-types

     grouping symmetric-key-grouping
       +-- algorithm           isa:symmetric-algorithm-type
       +-- key-format?         identityref
       +-- (key-type)
          +--:(key)
          |  +-- key?          binary
          +--:(hidden-key)
             +-- hidden-key?   empty
     grouping public-key-grouping
       +-- algorithm            iasa:asymmetric-algorithm-type
       +-- public-key-format?   identityref
       +-- public-key           binary
     grouping asymmetric-key-pair-grouping
       +-- algorithm                   iasa:asymmetric-algorithm-type
       +-- public-key-format?          identityref
       +-- public-key                  binary
       +-- private-key-format?         identityref
       +-- (private-key-type)
          +--:(private-key)
          |  +-- private-key?          binary
          +--:(hidden-private-key)
             +-- hidden-private-key?   empty
     grouping trust-anchor-cert-grouping
       +-- cert?                     trust-anchor-cert-cms
       +---n certificate-expiration
          +-- expiration-date    yang:date-and-time
     grouping trust-anchor-certs-grouping
       +-- cert*                     trust-anchor-cert-cms
       +---n certificate-expiration
          +-- expiration-date    yang:date-and-time
     grouping end-entity-cert-grouping
       +-- cert?                     end-entity-cert-cms
       +---n certificate-expiration
          +-- expiration-date    yang:date-and-time
     grouping end-entity-certs-grouping
       +-- cert*                     end-entity-cert-cms
       +---n certificate-expiration
          +-- expiration-date    yang:date-and-time



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     grouping asymmetric-key-pair-with-cert-grouping
       +-- algorithm
       |       iasa:asymmetric-algorithm-type
       +-- public-key-format?                      identityref
       +-- public-key                              binary
       +-- private-key-format?                     identityref
       +-- (private-key-type)
       |  +--:(private-key)
       |  |  +-- private-key?                      binary
       |  +--:(hidden-private-key)
       |     +-- hidden-private-key?               empty
       +-- cert?                                   end-entity-cert-cms
       +---n certificate-expiration
       |  +-- expiration-date    yang:date-and-time
       +---x generate-certificate-signing-request
          +---w input
          |  +---w subject       binary
          |  +---w attributes?   binary
          +--ro output
             +--ro certificate-signing-request    binary
     grouping asymmetric-key-pair-with-certs-grouping
       +-- algorithm
       |       iasa:asymmetric-algorithm-type
       +-- public-key-format?                      identityref
       +-- public-key                              binary
       +-- private-key-format?                     identityref
       +-- (private-key-type)
       |  +--:(private-key)
       |  |  +-- private-key?                      binary
       |  +--:(hidden-private-key)
       |     +-- hidden-private-key?               empty
       +-- certificates
       |  +-- certificate* [name]
       |     +-- name?                     string
       |     +-- cert?                     end-entity-cert-cms
       |     +---n certificate-expiration
       |        +-- expiration-date    yang:date-and-time
       +---x generate-certificate-signing-request
          +---w input
          |  +---w subject       binary
          |  +---w attributes?   binary
          +--ro output
             +--ro certificate-signing-request    binary








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2.2.  YANG Module

   This module has normative references to [RFC2404], [RFC3565],
   [RFC3686], [RFC4106], [RFC4253], [RFC4279], [RFC4309], [RFC4494],
   [RFC4543], [RFC4868], [RFC5280], [RFC5652], [RFC5656], [RFC6187],
   [RFC6991], [RFC7919], [RFC8268], [RFC8332], [RFC8341], [RFC8422],
   [RFC8446], and [ITU.X690.2015].

   This module has an informational reference to [RFC2986], [RFC3174],
   [RFC4493], [RFC5915], [RFC6125], [RFC6234], [RFC6239], [RFC6507],
   [RFC8017], [RFC8032], [RFC8439].

   <CODE BEGINS> file "ietf-crypto-types@2019-11-02.yang"

   module ietf-crypto-types {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:ietf-crypto-types";
     prefix ct;

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

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

     //import iana-hash-algs {
     //  prefix iha;
     //  reference
     //    "RFC XXXX: Common YANG Data Types for Cryptography";
     //}

     import iana-symmetric-algs {
       prefix isa;
       reference
         "RFC XXXX: Common YANG Data Types for Cryptography";
     }

     import iana-asymmetric-algs {
       prefix iasa;
       reference
         "RFC XXXX: Common YANG Data Types for Cryptography";
     }



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

     contact
       "WG Web:   <http://datatracker.ietf.org/wg/netconf/>
        WG List:  <mailto:netconf@ietf.org>
        Author:   Kent Watsen <mailto:kent+ietf@watsen.net>
        Author:   Wang Haiguang <wang.haiguang.shieldlab@huawei.com>";

     description
       "This module defines common YANG types for cryptographic
        applications.

        Copyright (c) 2019 IETF Trust and the persons identified
        as authors of the code. All rights reserved.

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

        This version of this YANG module is part of RFC XXXX
        (https://www.rfc-editor.org/info/rfcXXXX); 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 2019-11-02 {
       description
         "Initial version";
       reference
         "RFC XXXX: Common YANG Data Types for Cryptography";
     }

     /********************************************/
     /*   Identities for Key Format Structures   */
     /********************************************/

     /*** all key format types ****/

     identity key-format-base {



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       description "Base key-format identity for all keys.";
     }

     identity public-key-format {
       base "key-format-base";
       description "Base key-format identity for public keys.";
     }

     identity private-key-format {
       base "key-format-base";
       description "Base key-format identity for private keys.";
     }

     identity symmetric-key-format {
       base "key-format-base";
       description "Base key-format identity for symmetric keys.";
     }


     /**** for private keys ****/

     identity rsa-private-key-format {
         base "private-key-format";
         description "An RSAPrivateKey (from RFC 3447).";
     }

     identity ec-private-key-format {
         base "private-key-format";
         description "An ECPrivateKey (from RFC 5915)";
     }

     identity one-asymmetric-key-format {
         base "private-key-format";
         description "A OneAsymmetricKey (from RFC 5958).";
     }

     identity encrypted-private-key-format {
         base "private-key-format";
         description
           "A CMS EncryptedData structure (RFC 5652)
            containing a OneAsymmetricKey (RFC 5958).";
      }


     /**** for public keys ****/

     identity ssh-public-key-format {
         base "public-key-format";



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         description
           "The public key format described by RFC 4716.";
     }

     identity subject-public-key-info-format {
         base "public-key-format";
         description
           "A SubjectPublicKeyInfo (from RFC 5280).";
     }


     /**** for symmetric keys ****/

     identity octet-string-key-format {
         base "symmetric-key-format";
         description "An OctetString from ASN.1.";
           /*
           // Knowing that it is an "OctetString" isn't really helpful.
           // Knowing the length of the octet string would be helpful,
           // as it relates to the algorithm's block size.  We may want
           // to only (for now) use "one-symmetric-key-format" for
           // symmetric keys...were the usability issues Juergen
           // mentioned before only apply to asymmetric keys?
           */
     }

     identity one-symmetric-key-format {
         base "symmetric-key-format";
         description "A OneSymmetricKey (from RFC6031).";
     }

     identity encrypted-symmetric-key-format {
         base "symmetric-key-format";
         description
           "A CMS EncryptedData structure (RFC 5652)
            containing a OneSymmetricKey (RFC 6031).";
     }



     /***************************************************/
     /*   Typedefs for ASN.1 structures from RFC 5280   */
     /***************************************************/

     typedef x509 {
       type binary;
       description
         "A Certificate structure, as specified in RFC 5280,



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          encoded using ASN.1 distinguished encoding rules (DER),
          as specified in ITU-T X.690.";
       reference
         "RFC 5280:
            Internet X.509 Public Key Infrastructure Certificate
            and Certificate Revocation List (CRL) Profile
          ITU-T X.690:
            Information technology - ASN.1 encoding rules:
            Specification of Basic Encoding Rules (BER),
            Canonical Encoding Rules (CER) and Distinguished
            Encoding Rules (DER).";
     }

     typedef crl {
       type binary;
       description
         "A CertificateList structure, as specified in RFC 5280,
          encoded using ASN.1 distinguished encoding rules (DER),
          as specified in ITU-T X.690.";
       reference
         "RFC 5280:
            Internet X.509 Public Key Infrastructure Certificate
            and Certificate Revocation List (CRL) Profile
          ITU-T X.690:
            Information technology - ASN.1 encoding rules:
            Specification of Basic Encoding Rules (BER),
            Canonical Encoding Rules (CER) and Distinguished
            Encoding Rules (DER).";
     }

     /***********************************************/
     /*   Typedefs for ASN.1 structures from 5652   */
     /***********************************************/

     typedef cms {
       type binary;
       description
         "A ContentInfo structure, as specified in RFC 5652,
          encoded using ASN.1 distinguished encoding rules (DER),
          as specified in ITU-T X.690.";
       reference
         "RFC 5652:
            Cryptographic Message Syntax (CMS)
          ITU-T X.690:
            Information technology - ASN.1 encoding rules:
            Specification of Basic Encoding Rules (BER),
            Canonical Encoding Rules (CER) and Distinguished
            Encoding Rules (DER).";



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     }

     typedef data-content-cms {
       type cms;
       description
         "A CMS structure whose top-most content type MUST be the
          data content type, as described by Section 4 in RFC 5652.";
       reference
         "RFC 5652: Cryptographic Message Syntax (CMS)";
     }

     typedef signed-data-cms {
       type cms;
       description
         "A CMS structure whose top-most content type MUST be the
          signed-data content type, as described by Section 5 in
          RFC 5652.";
       reference
         "RFC 5652: Cryptographic Message Syntax (CMS)";
     }

     typedef enveloped-data-cms {
       type cms;
       description
         "A CMS structure whose top-most content type MUST be the
          enveloped-data content type, as described by Section 6
          in RFC 5652.";
       reference
         "RFC 5652: Cryptographic Message Syntax (CMS)";
     }

     typedef digested-data-cms {
       type cms;
       description
         "A CMS structure whose top-most content type MUST be the
          digested-data content type, as described by Section 7
          in RFC 5652.";
       reference
         "RFC 5652: Cryptographic Message Syntax (CMS)";
     }

     typedef encrypted-data-cms {
       type cms;
       description
         "A CMS structure whose top-most content type MUST be the
          encrypted-data content type, as described by Section 8
          in RFC 5652.";
       reference



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         "RFC 5652: Cryptographic Message Syntax (CMS)";
     }

     typedef authenticated-data-cms {
       type cms;
       description
         "A CMS structure whose top-most content type MUST be the
          authenticated-data content type, as described by Section 9
          in RFC 5652.";
       reference
         "RFC 5652: Cryptographic Message Syntax (CMS)";
     }

     /***************************************************/
     /*   Typedefs for structures related to !!FIXME!!  */
     /***************************************************/

     typedef psk {
       type binary;
       description
         "The binary key data for a PSK (pairwise-symmetric or
          pre-shared key).  FIXME: specify how it is formmated.";
     }

     typedef raw-public-key {
       type binary;
       description
         "The binary key data for a raw public key.
          FIXME: specify how it is formmated.";
     }

     /***************************************************/
     /*   Typedefs for structures related to RFC 4253   */
     /***************************************************/

     typedef ssh-host-key {
       type binary;
       description
         "The binary public key data for an SSH key, as
          specified by RFC 4253, Section 6.6, i.e.:

            string    certificate or public key format
                      identifier
            byte[n]   key/certificate data.";
       reference
         "RFC 4253: The Secure Shell (SSH) Transport Layer
                    Protocol";
     }



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     /*********************************************************/
     /*   Typedefs for ASN.1 structures related to RFC 5280   */
     /*********************************************************/

     typedef trust-anchor-cert-x509 {
       type x509;
       description
         "A Certificate structure that MUST encode a self-signed
          root certificate.";
     }

     typedef end-entity-cert-x509 {
       type x509;
       description
         "A Certificate structure that MUST encode a certificate
          that is neither self-signed nor having Basic constraint
          CA true.";
     }

     /*********************************************************/
     /*   Typedefs for ASN.1 structures related to RFC 5652   */
     /*********************************************************/

     typedef trust-anchor-cert-cms {
       type signed-data-cms;
       description
         "A CMS SignedData structure that MUST contain the chain of
          X.509 certificates needed to authenticate the certificate
          presented by a client or end-entity.

          The CMS MUST contain only a single chain of certificates.
          The client or end-entity certificate MUST only authenticate
          to last intermediate CA certificate listed in the chain.

          In all cases, the chain MUST include a self-signed root
          certificate.  In the case where the root certificate is
          itself the issuer of the client or end-entity certificate,
          only one certificate is present.

          This CMS structure MAY (as applicable where this type is
          used) also contain suitably fresh (as defined by local
          policy) revocation objects with which the device can
          verify the revocation status of the certificates.

          This CMS encodes the degenerate form of the SignedData
          structure that is commonly used to disseminate X.509
          certificates and revocation objects (RFC 5280).";
       reference



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         "RFC 5280:
            Internet X.509 Public Key Infrastructure Certificate
            and Certificate Revocation List (CRL) Profile.";
     }

     typedef end-entity-cert-cms {
       type signed-data-cms;
       description
         "A CMS SignedData structure that MUST contain the end
          entity certificate itself, and MAY contain any number
          of intermediate certificates leading up to a trust
          anchor certificate.  The trust anchor certificate
          MAY be included as well.

          The CMS MUST contain a single end entity certificate.
          The CMS MUST NOT contain any spurious certificates.

          This CMS structure MAY (as applicable where this type is
          used) also contain suitably fresh (as defined by local
          policy) revocation objects with which the device can
          verify the revocation status of the certificates.

          This CMS encodes the degenerate form of the SignedData
          structure that is commonly used to disseminate X.509
          certificates and revocation objects (RFC 5280).";
       reference
         "RFC 5280:
            Internet X.509 Public Key Infrastructure Certificate
            and Certificate Revocation List (CRL) Profile.";
     }

     typedef ssh-public-key-type {  // DELETE?
        type binary;
        description
          "The binary public key data for this SSH key, as
           specified by RFC 4253, Section 6.6, i.e.:

             string    certificate or public key format
                       identifier
             byte[n]   key/certificate data.";
        reference
          "RFC 4253: The Secure Shell (SSH) Transport
                     Layer Protocol";
     }

     /**********************************************/
     /*   Groupings for keys and/or certificates   */
     /**********************************************/



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     grouping symmetric-key-grouping {
       description
         "A symmetric key and algorithm.";
       leaf algorithm {
         type isa:symmetric-algorithm-type;
         mandatory true;
         description
           "The algorithm to be used when generating the key.";
         reference
           "RFC CCCC: Common YANG Data Types for Cryptography";
       }
       leaf key-format {
         nacm:default-deny-write;
         when "../key";
         type identityref {
           base symmetric-key-format;
         }
         description "Identifies the symmetric key's format.";
       }
       choice key-type {
         mandatory true;
         description
           "Choice between key types.";
         leaf key {
           nacm:default-deny-all;
           type binary;
           //must "../key-format";  FIXME: remove comment if approach ok
           description
             "The binary value of the key.  The interpretation of
              the value is defined by 'key-format'.  For example,
              FIXME.";
           reference
             "RFC XXXX: FIXME";
         }
         leaf hidden-key {
           nacm:default-deny-write;
           type empty;
           description
             "A permanently hidden key.  How such keys are created
              is outside the scope of this module.";
         }
       }
     }

     grouping public-key-grouping {
       description
         "A public key and its associated algorithm.";
       leaf algorithm {



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         nacm:default-deny-write;
         type iasa:asymmetric-algorithm-type;
         mandatory true;
         description
           "Identifies the key's algorithm.";
         reference
           "RFC CCCC: Common YANG Data Types for Cryptography";
       }
       leaf public-key-format {
         nacm:default-deny-write;
         when "../public-key";
         type identityref {
           base public-key-format;
         }
         description "Identifies the key's format.";
       }
       leaf public-key {
         nacm:default-deny-write;
         type binary;
         //must "../public-key-format"; FIXME: rm comment if approach ok
         mandatory true;
         description
           "The binary value of the public key.  The interpretation
            of the value is defined by 'public-key-format' field.";
       }
     }

     grouping asymmetric-key-pair-grouping {
       description
         "A private key and its associated public key and algorithm.";
       uses public-key-grouping;
       leaf private-key-format {
         nacm:default-deny-write;
         when "../private-key";
         type identityref {
           base private-key-format;
         }
         description "Identifies the key's format.";
       }
       choice private-key-type {
         mandatory true;
         description
           "Choice between key types.";
         leaf private-key {
           nacm:default-deny-all;
           type binary;
           //must "../private-key-format"; FIXME: rm comment if ok
           description



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             "The value of the binary key.  The key's value is
              interpreted by the 'private-key-format' field.";
         }
         leaf hidden-private-key {
           nacm:default-deny-write;
           type empty;
           description
             "A permanently hidden key.  How such keys are created
              is outside the scope of this module.";
         }
       }
     }

     grouping trust-anchor-cert-grouping {
       description
         "A trust anchor certificate, and a notification for when
          it is about to (or already has) expire.";
       leaf cert {
         nacm:default-deny-write;
         type trust-anchor-cert-cms;
         description
           "The binary certificate data for this certificate.";
         reference
           "RFC YYYY: Common YANG Data Types for Cryptography";
       }
       notification certificate-expiration {
         description
           "A notification indicating that the configured certificate
            is either about to expire or has already expired.  When to
            send notifications is an implementation specific decision,
            but it is RECOMMENDED that a notification be sent once a
            month for 3 months, then once a week for four weeks, and
            then once a day thereafter until the issue is resolved.";
         leaf expiration-date {
           type yang:date-and-time;
           mandatory true;
           description
             "Identifies the expiration date on the certificate.";
         }
       }
     }

     grouping trust-anchor-certs-grouping {
       description
         "A list of trust anchor certificates, and a notification
          for when one is about to (or already has) expire.";
       leaf-list cert {
         nacm:default-deny-write;



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         type trust-anchor-cert-cms;
         description
           "The binary certificate data for this certificate.";
         reference
           "RFC YYYY: Common YANG Data Types for Cryptography";
       }
       notification certificate-expiration {
         description
           "A notification indicating that the configured certificate
            is either about to expire or has already expired.  When to
            send notifications is an implementation specific decision,
            but it is RECOMMENDED that a notification be sent once a
            month for 3 months, then once a week for four weeks, and
            then once a day thereafter until the issue is resolved.";
         leaf expiration-date {
           type yang:date-and-time;
           mandatory true;
           description
             "Identifies the expiration date on the certificate.";
         }
       }
     }

     grouping end-entity-cert-grouping {
       description
         "An end entity certificate, and a notification for when
          it is about to (or already has) expire.  Implementations
          SHOULD assert that, where used, the end entity certificate
          contains the expected public key.";
       leaf cert {
         nacm:default-deny-write;
         type end-entity-cert-cms;
         description
           "The binary certificate data for this certificate.";
         reference
           "RFC YYYY: Common YANG Data Types for Cryptography";
       }
       notification certificate-expiration {
         description
           "A notification indicating that the configured certificate
            is either about to expire or has already expired.  When to
            send notifications is an implementation specific decision,
            but it is RECOMMENDED that a notification be sent once a
            month for 3 months, then once a week for four weeks, and
            then once a day thereafter until the issue is resolved.";
         leaf expiration-date {
           type yang:date-and-time;
           mandatory true;



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           description
             "Identifies the expiration date on the certificate.";
         }
       }
     }

     grouping end-entity-certs-grouping {
       description
         "A list of end entity certificates, and a notification for
          when one is about to (or already has) expire.";
       leaf-list cert {
         nacm:default-deny-write;
         type end-entity-cert-cms;
         description
           "The binary certificate data for this certificate.";
         reference
           "RFC YYYY: Common YANG Data Types for Cryptography";
       }
       notification certificate-expiration {
         description
           "A notification indicating that the configured certificate
            is either about to expire or has already expired.  When to
            send notifications is an implementation specific decision,
            but it is RECOMMENDED that a notification be sent once a
            month for 3 months, then once a week for four weeks, and
            then once a day thereafter until the issue is resolved.";
         leaf expiration-date {
           type yang:date-and-time;
           mandatory true;
           description
             "Identifies the expiration date on the certificate.";
         }
       }
     }

     grouping asymmetric-key-pair-with-cert-grouping {
       description
         "A private/public key pair and an associated certificate.
          Implementations SHOULD assert that certificates contain
          the matching public key.";
       uses asymmetric-key-pair-grouping;
       uses end-entity-cert-grouping;
       action generate-certificate-signing-request {
         nacm:default-deny-all;
         description
           "Generates a certificate signing request structure for
            the associated asymmetric key using the passed subject
            and attribute values.  The specified assertions need



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            to be appropriate for the certificate's use.  For
            example, an entity certificate for a TLS server
            SHOULD have values that enable clients to satisfy
            RFC 6125 processing.";
         input {
           leaf subject {
             type binary;
             mandatory true;
             description
               "The 'subject' field per the CertificationRequestInfo
                 structure as specified by RFC 2986, Section 4.1
                 encoded using the ASN.1 distinguished encoding
                 rules (DER), as specified in ITU-T X.690.";
             reference
               "RFC 2986:
                  PKCS #10: Certification Request Syntax
                            Specification Version 1.7.
                ITU-T X.690:
                  Information technology - ASN.1 encoding rules:
                  Specification of Basic Encoding Rules (BER),
                  Canonical Encoding Rules (CER) and Distinguished
                  Encoding Rules (DER).";
           }
           leaf attributes {
             type binary; // FIXME: does this need to be mandatory?
             description
               "The 'attributes' field from the structure
                CertificationRequestInfo as specified by RFC 2986,
                Section 4.1 encoded using the ASN.1 distinguished
                encoding rules (DER), as specified in ITU-T X.690.";
             reference
               "RFC 2986:
                  PKCS #10: Certification Request Syntax
                            Specification Version 1.7.
                ITU-T X.690:
                  Information technology - ASN.1 encoding rules:
                  Specification of Basic Encoding Rules (BER),
                  Canonical Encoding Rules (CER) and Distinguished
                  Encoding Rules (DER).";
           }
         }
         output {
           leaf certificate-signing-request {
             type binary;
             mandatory true;
             description
               "A CertificationRequest structure as specified by
                RFC 2986, Section 4.2 encoded using the ASN.1



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                distinguished encoding rules (DER), as specified
                in ITU-T X.690.";
             reference
               "RFC 2986:
                  PKCS #10: Certification Request Syntax
                            Specification Version 1.7.
                ITU-T X.690:
                  Information technology - ASN.1 encoding rules:
                  Specification of Basic Encoding Rules (BER),
                  Canonical Encoding Rules (CER) and Distinguished
                  Encoding Rules (DER).";
           }
         }
       } // generate-certificate-signing-request
     } // asymmetric-key-pair-with-cert-grouping

     grouping asymmetric-key-pair-with-certs-grouping {
       description
         "A private/public key pair and associated certificates.
          Implementations SHOULD assert that certificates contain
          the matching public key.";
       uses asymmetric-key-pair-grouping;
       container certificates {
         nacm:default-deny-write;
         description
           "Certificates associated with this asymmetric key.
            More than one certificate supports, for instance,
            a TPM-protected asymmetric key that has both IDevID
            and LDevID certificates associated.";
         list certificate {
           key "name";
           description
             "A certificate for this asymmetric key.";
           leaf name {
             type string;
             description
               "An arbitrary name for the certificate.  If the name
                matches the name of a certificate that exists
                independently in <operational> (i.e., an IDevID),
                then the 'cert' node MUST NOT be configured.";
           }
           uses end-entity-cert-grouping;
         }
       } // certificates
       action generate-certificate-signing-request {
         nacm:default-deny-all;
         description
           "Generates a certificate signing request structure for



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            the associated asymmetric key using the passed subject
            and attribute values.  The specified assertions need
            to be appropriate for the certificate's use.  For
            example, an entity certificate for a TLS server
            SHOULD have values that enable clients to satisfy
            RFC 6125 processing.";
         input {
           leaf subject {
             type binary;
             mandatory true;
             description
               "The 'subject' field per the CertificationRequestInfo
                 structure as specified by RFC 2986, Section 4.1
                 encoded using the ASN.1 distinguished encoding
                 rules (DER), as specified in ITU-T X.690.";
             reference
               "RFC 2986:
                  PKCS #10: Certification Request Syntax
                            Specification Version 1.7.
                ITU-T X.690:
                  Information technology - ASN.1 encoding rules:
                  Specification of Basic Encoding Rules (BER),
                  Canonical Encoding Rules (CER) and Distinguished
                  Encoding Rules (DER).";
           }
           leaf attributes {
             type binary; // FIXME: does this need to be mandatory?
             description
               "The 'attributes' field from the structure
                CertificationRequestInfo as specified by RFC 2986,
                Section 4.1 encoded using the ASN.1 distinguished
                encoding rules (DER), as specified in ITU-T X.690.";
             reference
               "RFC 2986:
                  PKCS #10: Certification Request Syntax
                            Specification Version 1.7.
                ITU-T X.690:
                  Information technology - ASN.1 encoding rules:
                  Specification of Basic Encoding Rules (BER),
                  Canonical Encoding Rules (CER) and Distinguished
                  Encoding Rules (DER).";
           }
         }
         output {
           leaf certificate-signing-request {
             type binary;
             mandatory true;
             description



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               "A CertificationRequest structure as specified by
                RFC 2986, Section 4.2 encoded using the ASN.1
                distinguished encoding rules (DER), as specified
                in ITU-T X.690.";
             reference
               "RFC 2986:
                  PKCS #10: Certification Request Syntax
                            Specification Version 1.7.
                ITU-T X.690:
                  Information technology - ASN.1 encoding rules:
                  Specification of Basic Encoding Rules (BER),
                  Canonical Encoding Rules (CER) and Distinguished
                  Encoding Rules (DER).";
           }
         }
       } // generate-certificate-signing-request
     } // asymmetric-key-pair-with-certs-grouping
   }

   <CODE ENDS>

2.3.  Examples

2.3.1.  The "asymmetric-key-pair-with-certs-grouping" Grouping

   The following example module illustrates the use of both the
   "symmetric-key-grouping" and the "asymmetric-key-pair-with-certs-
   grouping" groupings defined in the "ietf-crypto-types" module.

   module ex-crypto-types-usage {
     yang-version 1.1;

     namespace "http://example.com/ns/example-crypto-types-usage";
     prefix "ectu";

     import ietf-crypto-types {
       prefix ct;
       reference
         "RFC XXXX: Common YANG Data Types for Cryptography";
     }

     organization
      "Example Corporation";

     contact
      "Author: YANG Designer <mailto:yang.designer@example.com>";

     description



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      "This module illustrates the grouping
       defined in the crypto-types draft called
       'asymmetric-key-pair-with-certs-grouping'.";

     revision "1001-01-01" {
       description
        "Initial version";
       reference
        "RFC ????: Usage Example for RFC XXXX";
     }

     container symmetric-keys {
       description
         "A container of symmetric keys.";
       list symmetric-key {
         key name;
         description
           "A symmetric key";
         leaf name {
           type string;
           description
             "An arbitrary name for this key.";
         }
         uses ct:symmetric-key-grouping;
       }
     }
     container asymmetric-keys {
       description
         "A container of asymmetric keys.";
       list asymmetric-key {
         key name;
         leaf name {
           type string;
           description
             "An arbitrary name for this key.";
         }
         uses ct:asymmetric-key-pair-with-certs-grouping;
         description
           "An asymmetric key pair with associated certificates.";
       }
     }
   }

   Given the above example usage module, the following example
   illustrates some configured keys.

   <symmetric-keys
     xmlns="http://example.com/ns/example-crypto-types-usage"



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     xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-crypto-types">
     <symmetric-key>
       <name>ex-symmetric-key</name>
       <algorithm>aes-256-cbc</algorithm>
       <key-format>ct:octet-string-key-format</key-format>
       <key>base64encodedvalue==</key>
     </symmetric-key>
     <symmetric-key>
       <name>ex-hidden-symmetric-key</name>
       <algorithm>aes-256-cbc</algorithm>
       <hidden-key/>
     </symmetric-key>
   </symmetric-keys>

   <asymmetric-keys
     xmlns="http://example.com/ns/example-crypto-types-usage"
     xmlns:ct="urn:ietf:params:xml:ns:yang:ietf-crypto-types">
     <asymmetric-key>
       <name>ex-asymmetric-key</name>
       <algorithm>rsa2048</algorithm>
       <public-key-format>
         ct:subject-public-key-info-format
       </public-key-format>
       <public-key>base64encodedvalue==</public-key>
       <private-key-format>
         ct:rsa-private-key-format
       </private-key-format>
       <private-key>base64encodedvalue==</private-key>
       <certificates>
         <certificate>
           <name>ex-cert</name>
           <cert>base64encodedvalue==</cert>
         </certificate>
       </certificates>
     </asymmetric-key>
     <asymmetric-key>
       <name>ex-hidden-asymmetric-key</name>
       <algorithm>rsa2048</algorithm>
       <public-key-format>
         ct:subject-public-key-info-format
       </public-key-format>
       <public-key>base64encodedvalue==</public-key>
       <hidden-private-key/>
       <certificates>
         <certificate>
           <name>ex-hidden-key-cert</name>
           <cert>base64encodedvalue==</cert>
         </certificate>



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       </certificates>
     </asymmetric-key>
   </asymmetric-keys>

2.3.2.  The "generate-certificate-signing-request" Action

   The following example illustrates the "generate-certificate-signing-
   request" action with the NETCONF protocol.

   REQUEST

   <rpc message-id="101"
     xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
     <action xmlns="urn:ietf:params:xml:ns:yang:1">
       <asymmetric-keys
         xmlns="http://example.com/ns/example-crypto-types-usage">
         <asymmetric-key>
           <name>ex-key-sect571r1</name>
           <generate-certificate-signing-request>
             <subject>base64encodedvalue==</subject>
             <attributes>base64encodedvalue==</attributes>
           </generate-certificate-signing-request>
         </asymmetric-key>
       </asymmetric-keys>
     </action>
   </rpc>

   RESPONSE

   <rpc-reply message-id="101"
      xmlns="urn:ietf:params:xml:ns:netconf:base:1.0">
      <certificate-signing-request
        xmlns="http://example.com/ns/example-crypto-types-usage">
        base64encodedvalue==
      </certificate-signing-request>
   </rpc-reply>

2.3.3.  The "certificate-expiration" Notification

   The following example illustrates the "certificate-expiration"
   notification with the NETCONF protocol.










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   <notification
     xmlns="urn:ietf:params:xml:ns:netconf:notification:1.0">
     <eventTime>2018-05-25T00:01:00Z</eventTime>
     <keys xmlns="http://example.com/ns/example-crypto-types-usage">
       <key>
         <name>locally-defined key</name>
         <certificates>
           <certificate>
             <name>my-cert</name>
             <certificate-expiration>
               <expiration-date>
                 2018-08-05T14:18:53-05:00
               </expiration-date>
             </certificate-expiration>
           </certificate>
         </certificates>
       </key>
     </keys>
   </notification>

3.  The Symmetric Algorithms Module

3.1.  Tree Diagram

   This section provides a tree diagram [RFC8340] for the "iana-
   symmetric-algs" module.  Only the "container" statement is
   represented, as tree diagrams have no means to represent "typedef"
   statements.

   module: iana-symmetric-algs
     +--ro supported-symmetric-algorithms
        +--ro supported-symmetric-algorithm* [algorithm]
           +--ro algorithm    symmetric-algorithm-type

3.2.  YANG Module

   This module has normative references to FIXME...

   <CODE BEGINS> file "iana-symmetric-algs@2019-11-02.yang"

   module iana-symmetric-algs {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:iana-symmetric-algs";
     prefix isa;

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




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     contact
       "WG Web:   <http://datatracker.ietf.org/wg/netconf/>
        WG List:  <mailto:netconf@ietf.org>
        Author:   Kent Watsen <mailto:kent+ietf@watsen.net>
        Author:   Wang Haiguang <wang.haiguang.shieldlab@huawei.com>";

     description
       "This module defines a typedef for symmetric algorithms, and
        a container for a list of symmetric algorithms supported by
        the server.

        Copyright (c) 2019 IETF Trust and the persons identified
        as authors of the code. All rights reserved.
        Redistribution and use in source and binary forms, with
        or without modification, is permitted pursuant to, and
        subject to the license terms contained in, the Simplified
        BSD License set forth in Section 4.c of the IETF Trust's
        Legal Provisions Relating to IETF Documents
        (https://trustee.ietf.org/license-info).

        This version of this YANG module is part of RFC XXXX
        (https://www.rfc-editor.org/info/rfcXXXX); 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 2019-11-02 {
       description
         "Initial version";
       reference
         "RFC XXXX: Common YANG Data Types for Cryptography";
     }

     // Typedefs

     typedef symmetric-algorithm-type {
       type enumeration {
         enum aes-128-cbc {
           value 1;
           description
             "Encrypt message with AES algorithm in CBC mode with
              a key length of 128 bits.";
           reference



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             "RFC 3565: Use of the Advanced Encryption Standard (AES)
              Encryption Algorithm in Cryptographic Message Syntax
              (CMS)";
         }
         enum aes-192-cbc {
           value 2;
           description
             "Encrypt message with AES algorithm in CBC mode with
              a key length of 192 bits";
           reference
             "RFC 3565: Use of the Advanced Encryption Standard (AES)
              Encryption Algorithm in Cryptographic Message Syntax
              (CMS)";
         }
         enum aes-256-cbc {
           value 3;
           description
             "Encrypt message with AES algorithm in CBC mode with
              a key length of 256 bits";
           reference
             "RFC 3565: Use of the Advanced Encryption Standard (AES)
              Encryption Algorithm in Cryptographic Message Syntax
              (CMS)";
         }
         enum aes-128-ctr {
           value 4;
           description
             "Encrypt message with AES algorithm in CTR mode with
              a key length of 128 bits";
           reference
             "RFC 3686:
                Using Advanced Encryption Standard (AES) Counter
                Mode with IPsec Encapsulating Security Payload
                (ESP)";
         }
         enum aes-192-ctr {
           value 5;
           description
             "Encrypt message with AES algorithm in CTR mode with
              a key length of 192 bits";
           reference
             "RFC 3686:
                Using Advanced Encryption Standard (AES) Counter
                Mode with IPsec Encapsulating Security Payload
                (ESP)";
         }
         enum aes-256-ctr {
           value 6;



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           description
             "Encrypt message with AES algorithm in CTR mode with
              a key length of 256 bits";
           reference
             "RFC 3686:
                Using Advanced Encryption Standard (AES) Counter
                Mode with IPsec Encapsulating Security Payload
                (ESP)";
         }
         enum des3-cbc-sha1-kd {
           value 7;
           description
             "Encrypt message with 3DES algorithm in CBC mode
              with sha1 function for key derivation";
           reference
             "RFC 3961:
                Encryption and Checksum Specifications for
                Kerberos 5";
         }
         enum rc4-hmac {
           value 8;
           description
             "Encrypt message with rc4 algorithm";
           reference
             "RFC 4757:
                The RC4-HMAC Kerberos Encryption Types Used by
                Microsoft Windows";
         }
         enum rc4-hmac-exp {
           value 9;
           description
             "Encrypt message with rc4 algorithm that is exportable";
           reference
             "RFC 4757:
                The RC4-HMAC Kerberos Encryption Types Used by
                Microsoft Windows";
         }
       }
       description
         "A typedef enumerating various symmetric key algorithms.";
     }

     // Protocol-accessible Nodes

     container supported-symmetric-algorithms {
       config false;
       description
         "A container for a list of supported symmetric algorithms.



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          How algorithms come to be supported is outside the scope
          of this module.";
       list supported-symmetric-algorithm {
         key algorithm;
         description
           "A lists of symmetric algorithms supported by the server.";
         leaf algorithm {
           type symmetric-algorithm-type;
           description
             "An symmetric algorithms supported by the server.";
         }
       }
     }

   }

   <CODE ENDS>

3.3.  Examples

   The following example illustrates the "supported-symmetric-
   algorithms" "container" statement with the NETCONF protocol.

   <supported-symmetric-algorithms
     xmlns="urn:ietf:params:xml:ns:yang:iana-symmetric-algs">
     <supported-symmetric-algorithm>
       <algorithm>aes-128-cbc</algorithm>
     </supported-symmetric-algorithm>
     <supported-symmetric-algorithm>
       <algorithm>aes-256-cbc</algorithm>
     </supported-symmetric-algorithm>
   </supported-symmetric-algorithms>

4.  The Asymmetric Algorithms Module

4.1.  Tree Diagram

   This section provides a tree diagram [RFC8340] for the "iana-
   asymmetric-algs" module.  Only the "container" statement is
   represented, as tree diagrams have no means to represent "typedef"
   statements.

   module: iana-asymmetric-algs
     +--ro supported-asymmetric-algorithms
        +--ro supported-asymmetric-algorithm* [algorithm]
           +--ro algorithm    asymmetric-algorithm-type





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4.2.  YANG Module

   This module has normative references to FIXME...

   <CODE BEGINS> file "iana-asymmetric-algs@2019-11-02.yang"

   module iana-asymmetric-algs {
     yang-version 1.1;
     namespace "urn:ietf:params:xml:ns:yang:iana-asymmetric-algs";
     prefix iasa;

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

     contact
       "WG Web:   <http://datatracker.ietf.org/wg/netconf/>
        WG List:  <mailto:netconf@ietf.org>
        Author:   Kent Watsen <mailto:kent+ietf@watsen.net>
        Author:   Wang Haiguang <wang.haiguang.shieldlab@huawei.com>";

     description
       "This module defines a typedef for asymmetric algorithms, and
        a container for a list of asymmetric algorithms supported by
        the server.

        Copyright (c) 2019 IETF Trust and the persons identified
        as authors of the code. All rights reserved.
        Redistribution and use in source and binary forms, with
        or without modification, is permitted pursuant to, and
        subject to the license terms contained in, the Simplified
        BSD License set forth in Section 4.c of the IETF Trust's
        Legal Provisions Relating to IETF Documents
        (https://trustee.ietf.org/license-info).

        This version of this YANG module is part of RFC XXXX
        (https://www.rfc-editor.org/info/rfcXXXX); 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 2019-11-02 {
       description
         "Initial version";



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       reference
         "RFC XXXX: Common YANG Data Types for Cryptography";
     }

     // Typedefs

     typedef asymmetric-algorithm-type {
       type enumeration {
         enum rsa1024 {
           value 1;
           description
             "The RSA algorithm using a 1024-bit key.";
           reference
             "RFC 8017: PKCS #1: RSA Cryptography
              Specifications Version 2.2.";
         }
         enum rsa2048 {
           value 2;
           description
             "The RSA algorithm using a 2048-bit key.";
           reference
             "RFC 8017:
              PKCS #1: RSA Cryptography Specifications Version 2.2.";
         }
         enum rsa3072 {
           value 3;
           description
             "The RSA algorithm using a 3072-bit key.";
           reference
             "RFC 8017:
              PKCS #1: RSA Cryptography Specifications Version 2.2.";
         }
         enum rsa4096 {
           value 4;
           description
             "The RSA algorithm using a 4096-bit key.";
           reference
             "RFC 8017:
              PKCS #1: RSA Cryptography Specifications Version 2.2.";
         }
         enum rsa7680 {
           value 5;
           description
             "The RSA algorithm using a 7680-bit key.";
           reference
             "RFC 8017:
              PKCS #1: RSA Cryptography Specifications Version 2.2.";
         }



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         enum rsa15360 {
           value 6;
           description
             "The RSA algorithm using a 15360-bit key.";
           reference
             "RFC 8017:
              PKCS #1: RSA Cryptography Specifications Version 2.2.";
         }
         enum secp192r1 {
           value 7;
           description
             "The asymmetric algorithm using a NIST P192 Curve.";
           reference
             "RFC 6090:
                Fundamental Elliptic Curve Cryptography Algorithms.
              RFC 5480:
                 Elliptic Curve Cryptography Subject Public Key
                 Information.";
         }
         enum secp224r1 {
           value 8;
           description
             "The asymmetric algorithm using a NIST P224 Curve.";
           reference
             "RFC 6090:
                Fundamental Elliptic Curve Cryptography Algorithms.
              RFC 5480:
                Elliptic Curve Cryptography Subject Public Key
                Information.";
         }
         enum secp256r1 {
           value 9;
           description
             "The asymmetric algorithm using a NIST P256 Curve.";
           reference
             "RFC 6090:
                Fundamental Elliptic Curve Cryptography Algorithms.
              RFC 5480:
                Elliptic Curve Cryptography Subject Public Key
                Information.";
         }
         enum secp384r1 {
           value 10;
           description
             "The asymmetric algorithm using a NIST P384 Curve.";
           reference
             "RFC 6090:
                Fundamental Elliptic Curve Cryptography Algorithms.



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              RFC 5480:
                Elliptic Curve Cryptography Subject Public Key
                Information.";
         }
         enum secp521r1 {
           value 11;
           description
             "The asymmetric algorithm using a NIST P521 Curve.";
           reference
             "RFC 6090:
                Fundamental Elliptic Curve Cryptography Algorithms.
              RFC 5480:
                Elliptic Curve Cryptography Subject Public Key
                Information.";
         }
         enum x25519 {
           value 12;
           description
             "The asymmetric algorithm using a x.25519 Curve.";
           reference
             "RFC 7748:
                Elliptic Curves for Security.";
         }
         enum x448 {
           value 13;
           description
             "The asymmetric algorithm using a x.448 Curve.";
           reference
             "RFC 7748:
                Elliptic Curves for Security.";
         }
       }
       description
         "A typedef enumerating various asymmetric key algorithms.";
     }

     // Protocol-accessible Nodes

     container supported-asymmetric-algorithms {
       config false;
       description
         "A container for a list of supported asymmetric algorithms.
          How algorithms come to be supported is outside the scope
          of this module.";
       list supported-asymmetric-algorithm {
         key algorithm;
         description
           "A lists of asymmetric algorithms supported by the server.";



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         leaf algorithm {
           type asymmetric-algorithm-type;
           description
             "An asymmetric algorithms supported by the server.";
         }
       }
     }

   }

   <CODE ENDS>

4.3.  Examples

   The following example illustrates the "supported-asymmetric-
   algorithms" "container" statement with the NETCONF protocol.

   <supported-asymmetric-algorithms
     xmlns="urn:ietf:params:xml:ns:yang:iana-asymmetric-algs">
     <supported-asymmetric-algorithm>
       <algorithm>rsa2048</algorithm>
     </supported-asymmetric-algorithm>
     <supported-asymmetric-algorithm>
       <algorithm>secp256r1</algorithm>
     </supported-asymmetric-algorithm>
   </supported-asymmetric-algorithms>

5.  The Hash Algorithms Module

5.1.  Tree Diagram

   This section provides a tree diagram [RFC8340] for the "iana-hash-
   algs" module.  Only the "container" statement is represented, as tree
   diagrams have no means to represent "typedef" statements.

   module: iana-hash-algs
     +--ro supported-hash-algorithms
        +--ro supported-hash-algorithm* [algorithm]
           +--ro algorithm    hash-algorithm-type

5.2.  YANG Module

   This module has normative references to FIXME...

   <CODE BEGINS> file "iana-hash-algs@2019-11-02.yang"

   module iana-hash-algs {
     yang-version 1.1;



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     namespace "urn:ietf:params:xml:ns:yang:iana-hash-algs";
     prefix iha;

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

     contact
       "WG Web:   <http://datatracker.ietf.org/wg/netconf/>
        WG List:  <mailto:netconf@ietf.org>
        Author:   Kent Watsen <mailto:kent+ietf@watsen.net>
        Author:   Wang Haiguang <wang.haiguang.shieldlab@huawei.com>";

     description
       "This module defines a typedef for hash algorithms, and
        a container for a list of hash algorithms supported by
        the server.

        Copyright (c) 2019 IETF Trust and the persons identified
        as authors of the code. All rights reserved.
        Redistribution and use in source and binary forms, with
        or without modification, is permitted pursuant to, and
        subject to the license terms contained in, the Simplified
        BSD License set forth in Section 4.c of the IETF Trust's
        Legal Provisions Relating to IETF Documents
        (https://trustee.ietf.org/license-info).

        This version of this YANG module is part of RFC XXXX
        (https://www.rfc-editor.org/info/rfcXXXX); 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 2019-11-02 {
       description
         "Initial version";
       reference
         "RFC XXXX: Common YANG Data Types for Cryptography";
     }

     // Typedefs

     typedef hash-algorithm-type {
       type enumeration {



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         enum sha1 {
           value 1;
           status obsolete;
           description
             "The SHA1 algorithm.";
           reference
             "RFC 3174: US Secure Hash Algorithms 1 (SHA1).";
         }
         enum sha-224 {
           value 2;
           description
             "The SHA-224 algorithm.";
           reference
             "RFC 6234: US Secure Hash Algorithms.";
         }
         enum sha-256 {
           value 3;
           description
             "The SHA-256 algorithm.";
           reference
             "RFC 6234: US Secure Hash Algorithms.";
         }
         enum sha-384 {
           value 4;
           description
             "The SHA-384 algorithm.";
           reference
             "RFC 6234: US Secure Hash Algorithms.";
         }
         enum sha-512 {
           value 5;
           description
             "The SHA-512 algorithm.";
           reference
             "RFC 6234: US Secure Hash Algorithms.";
         }
         enum shake-128 {
           value 6;
           description
             "The SHA3 algorithm with 128-bits output.";
           reference
             "National Institute of Standards and Technology,
              SHA-3 Standard: Permutation-Based Hash and
              Extendable-Output Functions, FIPS PUB 202, DOI
              10.6028/NIST.FIPS.202, August 2015.";
         }
         enum shake-224 {
           value 7;



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           description
             "The SHA3 algorithm with 224-bits output.";
           reference
             "National Institute of Standards and Technology,
              SHA-3 Standard: Permutation-Based Hash and
              Extendable-Output Functions, FIPS PUB 202, DOI
              10.6028/NIST.FIPS.202, August 2015.";
         }
         enum shake-256 {
           value 8;
           description
             "The SHA3 algorithm with 256-bits output.";
           reference
             "National Institute of Standards and Technology,
              SHA-3 Standard: Permutation-Based Hash and
              Extendable-Output Functions, FIPS PUB 202, DOI
              10.6028/NIST.FIPS.202, August 2015.";
         }
         enum shake-384 {
           value 9;
           description
             "The SHA3 algorithm with 384-bits output.";
           reference
             "National Institute of Standards and Technology,
              SHA-3 Standard: Permutation-Based Hash and
              Extendable-Output Functions, FIPS PUB 202, DOI
              10.6028/NIST.FIPS.202, August 2015.";
         }
         enum shake-512 {
           value 10;
           description
             "The SHA3 algorithm with 384-bits output.";
           reference
             "National Institute of Standards and Technology,
              SHA-3 Standard: Permutation-Based Hash and
              Extendable-Output Functions, FIPS PUB 202, DOI
              10.6028/NIST.FIPS.202, August 2015.";
         }
       }
       description
         "A typedef enumerating various hash key algorithms.";
     }

     // Protocol-accessible Nodes

     container supported-hash-algorithms {
       config false;
       description



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         "A container for a list of supported hash algorithms.
          How algorithms come to be supported is outside the
          scope of this module.";
       list supported-hash-algorithm {
         key algorithm;
         description
           "A lists of hash algorithms supported by the server.";
         leaf algorithm {
           type hash-algorithm-type;
           description
             "An hash algorithms supported by the server.";
         }
       }
     }

   }

   <CODE ENDS>

5.3.  Examples

   The following example illustrates the "supported-hash-algorithms"
   "container" statement with the NETCONF protocol.

   <supported-hash-algorithms
     xmlns="urn:ietf:params:xml:ns:yang:iana-hash-algs">
     <supported-hash-algorithm>
       <algorithm>sha-256</algorithm>
     </supported-hash-algorithm>
     <supported-hash-algorithm>
       <algorithm>sha-512</algorithm>
     </supported-hash-algorithm>
   </supported-hash-algorithms>

6.  Security Considerations

6.1.  Support for Algorithms

   In order to use YANG identities for algorithm identifiers, only the
   most commonly used RSA key lengths are supported for the RSA
   algorithm.  Additional key lengths can be defined in another module
   or added into a future version of this document.

   This document limits the number of elliptical curves supported.  This
   was done to match industry trends and IETF best practice (e.g.,
   matching work being done in TLS 1.3).  If additional algorithms are
   needed, they can be defined by another module or added into a future
   version of this document.



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6.2.  No Support for CRMF

   This document uses PKCS #10 [RFC2986] for the "generate-certificate-
   signing-request" action.  The use of Certificate Request Message
   Format (CRMF) [RFC4211] was considered, but is was unclear if there
   was market demand for it.  If it is desired to support CRMF in the
   future, a backwards compatible solution can be defined at that time.

6.3.  Access to Data Nodes

   The YANG module in this document defines "grouping" statements that
   are designed to be accessed via YANG based management protocols, such
   as NETCONF [RFC6241] and RESTCONF [RFC8040].  Both of these protocols
   have mandatory-to-implement secure transport layers (e.g., SSH, TLS)
   with mutual authentication.

   The NETCONF access control model (NACM) [RFC8341] provides the means
   to restrict access for particular users to a pre-configured subset of
   all available protocol operations and content.

   Since the module in this document only define groupings, these
   considerations are primarily for the designers of other modules that
   use these groupings.

   There are a number of data nodes defined by the grouping statements
   that are writable/creatable/deletable (i.e., config true, which is
   the default).  Some of these data nodes may be considered sensitive
   or vulnerable in some network environments.  Write operations (e.g.,
   edit-config) to these data nodes without proper protection can have a
   negative effect on network operations.  These are the subtrees and
   data nodes and their sensitivity/vulnerability:

      *: All of the data nodes defined by all the groupings are
         considered sensitive to write operations.  For instance, the
         modification of a public key or a certificate can dramatically
         alter the implemented security policy.  For this reason, the
         NACM extension "default-deny-write" has been applied to all the
         data nodes defined by all the groupings.

   Some of the readable data nodes in the YANG module may be considered
   sensitive or vulnerable in some network environments.  It is thus
   important to control read access (e.g., via get, get-config, or
   notification) to these data nodes.  These are the subtrees and data
   nodes and their sensitivity/vulnerability:

      /private-key:  The "private-key" node defined in the "asymmetric-
         key-pair-grouping" grouping is additionally sensitive to read
         operations such that, in normal use cases, it should never be



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         returned to a client.  For this reason, the NACM extension
         "default-deny-all" has been applied to it here.

   Some of the operations in this YANG module may be considered
   sensitive or vulnerable in some network environments.  It is thus
   important to control access to these operations.  These are the
   operations and their sensitivity/vulnerability:

      *: All of the "action" statements defined by groupings SHOULD only
         be executed by authorized users.  For this reason, the NACM
         extension "default-deny-all" has been applied to all of them.
         Note that NACM uses "default-deny-all" to protect "RPC" and
         "action" statements; it does not define, e.g., an extension
         called "default-deny-execute".

      generate-certificate-signing-request:  For this action, it is
         RECOMMENDED that implementations assert channel binding
         [RFC5056], so as to ensure that the application layer that sent
         the request is the same as the device authenticated when the
         secure transport layer was established.

7.  IANA Considerations

7.1.  The IETF XML Registry

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

      URI: urn:ietf:params:xml:ns:yang:ietf-crypto-types
      Registrant Contact: The NETCONF WG of the IETF.
      XML: N/A, the requested URI is an XML namespace.

      URI: urn:ietf:params:xml:ns:yang:iana-symmetric-algs
      Registrant Contact: The NETCONF WG of the IETF.
      XML: N/A, the requested URI is an XML namespace.

      URI: urn:ietf:params:xml:ns:yang:iana-ssymmetric-algs
      Registrant Contact: The NETCONF WG of the IETF.
      XML: N/A, the requested URI is an XML namespace.

      URI: urn:ietf:params:xml:ns:yang:iana-hash-algs
      Registrant Contact: The NETCONF WG of the IETF.
      XML: N/A, the requested URI is an XML namespace.







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7.2.  The YANG Module Names Registry

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

      name:         ietf-crypto-types
      namespace:    urn:ietf:params:xml:ns:yang:ietf-crypto-types
      prefix:       ct
      reference:    RFC XXXX

      name:         iana-symmetric-algs
      namespace:    urn:ietf:params:xml:ns:yang:iana-symmetric-algs
      prefix:       isa
      reference:    RFC XXXX

      name:         iana-asymmetric-algs
      namespace:    urn:ietf:params:xml:ns:yang:iana-asymmetric-algs
      prefix:       iasa
      reference:    RFC XXXX

      name:         iana-hash-algs
      namespace:    urn:ietf:params:xml:ns:yang:iana-hash-algs
      prefix:       iha
      reference:    RFC XXXX

8.  References

8.1.  Normative References

   [ITU.X690.2015]
              International Telecommunication Union, "Information
              Technology - ASN.1 encoding rules: Specification of Basic
              Encoding Rules (BER), Canonical Encoding Rules (CER) and
              Distinguished Encoding Rules (DER)", ITU-T Recommendation
              X.690, ISO/IEC 8825-1, August 2015,
              <https://www.itu.int/rec/T-REC-X.690/>.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

   [RFC2404]  Madson, C. and R. Glenn, "The Use of HMAC-SHA-1-96 within
              ESP and AH", RFC 2404, DOI 10.17487/RFC2404, November
              1998, <https://www.rfc-editor.org/info/rfc2404>.





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   [RFC3565]  Schaad, J., "Use of the Advanced Encryption Standard (AES)
              Encryption Algorithm in Cryptographic Message Syntax
              (CMS)", RFC 3565, DOI 10.17487/RFC3565, July 2003,
              <https://www.rfc-editor.org/info/rfc3565>.

   [RFC3686]  Housley, R., "Using Advanced Encryption Standard (AES)
              Counter Mode With IPsec Encapsulating Security Payload
              (ESP)", RFC 3686, DOI 10.17487/RFC3686, January 2004,
              <https://www.rfc-editor.org/info/rfc3686>.

   [RFC4106]  Viega, J. and D. McGrew, "The Use of Galois/Counter Mode
              (GCM) in IPsec Encapsulating Security Payload (ESP)",
              RFC 4106, DOI 10.17487/RFC4106, June 2005,
              <https://www.rfc-editor.org/info/rfc4106>.

   [RFC4253]  Ylonen, T. and C. Lonvick, Ed., "The Secure Shell (SSH)
              Transport Layer Protocol", RFC 4253, DOI 10.17487/RFC4253,
              January 2006, <https://www.rfc-editor.org/info/rfc4253>.

   [RFC4279]  Eronen, P., Ed. and H. Tschofenig, Ed., "Pre-Shared Key
              Ciphersuites for Transport Layer Security (TLS)",
              RFC 4279, DOI 10.17487/RFC4279, December 2005,
              <https://www.rfc-editor.org/info/rfc4279>.

   [RFC4309]  Housley, R., "Using Advanced Encryption Standard (AES) CCM
              Mode with IPsec Encapsulating Security Payload (ESP)",
              RFC 4309, DOI 10.17487/RFC4309, December 2005,
              <https://www.rfc-editor.org/info/rfc4309>.

   [RFC4494]  Song, JH., Poovendran, R., and J. Lee, "The AES-CMAC-96
              Algorithm and Its Use with IPsec", RFC 4494,
              DOI 10.17487/RFC4494, June 2006,
              <https://www.rfc-editor.org/info/rfc4494>.

   [RFC4543]  McGrew, D. and J. Viega, "The Use of Galois Message
              Authentication Code (GMAC) in IPsec ESP and AH", RFC 4543,
              DOI 10.17487/RFC4543, May 2006,
              <https://www.rfc-editor.org/info/rfc4543>.

   [RFC4868]  Kelly, S. and S. Frankel, "Using HMAC-SHA-256, HMAC-SHA-
              384, and HMAC-SHA-512 with IPsec", RFC 4868,
              DOI 10.17487/RFC4868, May 2007,
              <https://www.rfc-editor.org/info/rfc4868>.








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   [RFC5280]  Cooper, D., Santesson, S., Farrell, S., Boeyen, S.,
              Housley, R., and W. Polk, "Internet X.509 Public Key
              Infrastructure Certificate and Certificate Revocation List
              (CRL) Profile", RFC 5280, DOI 10.17487/RFC5280, May 2008,
              <https://www.rfc-editor.org/info/rfc5280>.

   [RFC5652]  Housley, R., "Cryptographic Message Syntax (CMS)", STD 70,
              RFC 5652, DOI 10.17487/RFC5652, September 2009,
              <https://www.rfc-editor.org/info/rfc5652>.

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

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

   [RFC6991]  Schoenwaelder, J., Ed., "Common YANG Data Types",
              RFC 6991, DOI 10.17487/RFC6991, July 2013,
              <https://www.rfc-editor.org/info/rfc6991>.

   [RFC7919]  Gillmor, D., "Negotiated Finite Field Diffie-Hellman
              Ephemeral Parameters for Transport Layer Security (TLS)",
              RFC 7919, DOI 10.17487/RFC7919, August 2016,
              <https://www.rfc-editor.org/info/rfc7919>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8268]  Baushke, M., "More Modular Exponentiation (MODP) Diffie-
              Hellman (DH) Key Exchange (KEX) Groups for Secure Shell
              (SSH)", RFC 8268, DOI 10.17487/RFC8268, December 2017,
              <https://www.rfc-editor.org/info/rfc8268>.

   [RFC8332]  Bider, D., "Use of RSA Keys with SHA-256 and SHA-512 in
              the Secure Shell (SSH) Protocol", RFC 8332,
              DOI 10.17487/RFC8332, March 2018,
              <https://www.rfc-editor.org/info/rfc8332>.






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   [RFC8341]  Bierman, A. and M. Bjorklund, "Network Configuration
              Access Control Model", STD 91, RFC 8341,
              DOI 10.17487/RFC8341, March 2018,
              <https://www.rfc-editor.org/info/rfc8341>.

   [RFC8422]  Nir, Y., Josefsson, S., and M. Pegourie-Gonnard, "Elliptic
              Curve Cryptography (ECC) Cipher Suites for Transport Layer
              Security (TLS) Versions 1.2 and Earlier", RFC 8422,
              DOI 10.17487/RFC8422, August 2018,
              <https://www.rfc-editor.org/info/rfc8422>.

   [RFC8446]  Rescorla, E., "The Transport Layer Security (TLS) Protocol
              Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018,
              <https://www.rfc-editor.org/info/rfc8446>.

8.2.  Informative References

   [RFC2986]  Nystrom, M. and B. Kaliski, "PKCS #10: Certification
              Request Syntax Specification Version 1.7", RFC 2986,
              DOI 10.17487/RFC2986, November 2000,
              <https://www.rfc-editor.org/info/rfc2986>.

   [RFC3174]  Eastlake 3rd, D. and P. Jones, "US Secure Hash Algorithm 1
              (SHA1)", RFC 3174, DOI 10.17487/RFC3174, September 2001,
              <https://www.rfc-editor.org/info/rfc3174>.

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

   [RFC4211]  Schaad, J., "Internet X.509 Public Key Infrastructure
              Certificate Request Message Format (CRMF)", RFC 4211,
              DOI 10.17487/RFC4211, September 2005,
              <https://www.rfc-editor.org/info/rfc4211>.

   [RFC4493]  Song, JH., Poovendran, R., Lee, J., and T. Iwata, "The
              AES-CMAC Algorithm", RFC 4493, DOI 10.17487/RFC4493, June
              2006, <https://www.rfc-editor.org/info/rfc4493>.

   [RFC5056]  Williams, N., "On the Use of Channel Bindings to Secure
              Channels", RFC 5056, DOI 10.17487/RFC5056, November 2007,
              <https://www.rfc-editor.org/info/rfc5056>.

   [RFC5915]  Turner, S. and D. Brown, "Elliptic Curve Private Key
              Structure", RFC 5915, DOI 10.17487/RFC5915, June 2010,
              <https://www.rfc-editor.org/info/rfc5915>.





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   [RFC6020]  Bjorklund, M., Ed., "YANG - A Data Modeling Language for
              the Network Configuration Protocol (NETCONF)", RFC 6020,
              DOI 10.17487/RFC6020, October 2010,
              <https://www.rfc-editor.org/info/rfc6020>.

   [RFC6125]  Saint-Andre, P. and J. Hodges, "Representation and
              Verification of Domain-Based Application Service Identity
              within Internet Public Key Infrastructure Using X.509
              (PKIX) Certificates in the Context of Transport Layer
              Security (TLS)", RFC 6125, DOI 10.17487/RFC6125, March
              2011, <https://www.rfc-editor.org/info/rfc6125>.

   [RFC6234]  Eastlake 3rd, D. and T. Hansen, "US Secure Hash Algorithms
              (SHA and SHA-based HMAC and HKDF)", RFC 6234,
              DOI 10.17487/RFC6234, May 2011,
              <https://www.rfc-editor.org/info/rfc6234>.

   [RFC6239]  Igoe, K., "Suite B Cryptographic Suites for Secure Shell
              (SSH)", RFC 6239, DOI 10.17487/RFC6239, May 2011,
              <https://www.rfc-editor.org/info/rfc6239>.

   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
              and A. Bierman, Ed., "Network Configuration Protocol
              (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
              <https://www.rfc-editor.org/info/rfc6241>.

   [RFC6507]  Groves, M., "Elliptic Curve-Based Certificateless
              Signatures for Identity-Based Encryption (ECCSI)",
              RFC 6507, DOI 10.17487/RFC6507, February 2012,
              <https://www.rfc-editor.org/info/rfc6507>.

   [RFC8017]  Moriarty, K., Ed., Kaliski, B., Jonsson, J., and A. Rusch,
              "PKCS #1: RSA Cryptography Specifications Version 2.2",
              RFC 8017, DOI 10.17487/RFC8017, November 2016,
              <https://www.rfc-editor.org/info/rfc8017>.

   [RFC8032]  Josefsson, S. and I. Liusvaara, "Edwards-Curve Digital
              Signature Algorithm (EdDSA)", RFC 8032,
              DOI 10.17487/RFC8032, January 2017,
              <https://www.rfc-editor.org/info/rfc8032>.

   [RFC8040]  Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/info/rfc8040>.

   [RFC8340]  Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams",
              BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018,
              <https://www.rfc-editor.org/info/rfc8340>.



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   [RFC8439]  Nir, Y. and A. Langley, "ChaCha20 and Poly1305 for IETF
              Protocols", RFC 8439, DOI 10.17487/RFC8439, June 2018,
              <https://www.rfc-editor.org/info/rfc8439>.
















































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Appendix A.  Change Log

A.1.  I-D to 00

   o  Removed groupings and notifications.

   o  Added typedefs for identityrefs.

   o  Added typedefs for other RFC 5280 structures.

   o  Added typedefs for other RFC 5652 structures.

   o  Added convenience typedefs for RFC 4253, RFC 5280, and RFC 5652.

A.2.  00 to 01

   o  Moved groupings from the draft-ietf-netconf-keystore here.

A.3.  01 to 02

   o  Removed unwanted "mandatory" and "must" statements.

   o  Added many new crypto algorithms (thanks Haiguang!)

   o  Clarified in asymmetric-key-pair-with-certs-grouping, in
      certificates/certificate/name/description, that if the name MUST
      NOT match the name of a certificate that exists independently in
      <operational>, enabling certs installed by the manufacturer (e.g.,
      an IDevID).

A.4.  02 to 03

   o  renamed base identity 'asymmetric-key-encryption-algorithm' to
      'asymmetric-key-algorithm'.

   o  added new 'asymmetric-key-algorithm' identities for secp192r1,
      secp224r1, secp256r1, secp384r1, and secp521r1.

   o  removed 'mac-algorithm' identities for mac-aes-128-ccm, mac-aes-
      192-ccm, mac-aes-256-ccm, mac-aes-128-gcm, mac-aes-192-gcm, mac-
      aes-256-gcm, and mac-chacha20-poly1305.

   o  for all -cbc and -ctr identities, renamed base identity
      'symmetric-key-encryption-algorithm' to 'encryption-algorithm'.

   o  for all -ccm and -gcm identities, renamed base identity
      'symmetric-key-encryption-algorithm' to 'encryption-and-mac-
      algorithm' and renamed the identity to remove the "enc-" prefix.



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   o  for all the 'signature-algorithm' based identities, renamed from
      'rsa-*' to 'rsassa-*'.

   o  removed all of the "x509v3-" prefixed 'signature-algorithm' based
      identities.

   o  added 'key-exchange-algorithm' based identities for 'rsaes-oaep'
      and 'rsaes-pkcs1-v1_5'.

   o  renamed typedef 'symmetric-key-encryption-algorithm-ref' to
      'symmetric-key-algorithm-ref'.

   o  renamed typedef 'asymmetric-key-encryption-algorithm-ref' to
      'asymmetric-key-algorithm-ref'.

   o  added typedef 'encryption-and-mac-algorithm-ref'.

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

A.5.  03 to 04

   o  ran YANG module through formatter.

A.6.  04 to 05

   o  fixed broken symlink causing reformatted YANG module to not show.

A.7.  05 to 06

   o  Added NACM annotations.

   o  Updated Security Considerations section.

   o  Added 'asymmetric-key-pair-with-cert-grouping' grouping.

   o  Removed text from 'permanently-hidden' enum regarding such keys
      not being backed up or restored.

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

   o  Added an explanation to the 'public-key-grouping' and 'asymmetric-
      key-pair-grouping' statements as for why the nodes are not
      mandatory (e.g., because they may exist only in <operational>.






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   o  Added 'must' expressions to the 'public-key-grouping' and
      'asymmetric-key-pair-grouping' statements ensuring sibling nodes
      are either all exist or do not all exist.

   o  Added an explanation to the 'permanently-hidden' that the value
      cannot be configured directly by clients and servers MUST fail any
      attempt to do so.

   o  Added 'trust-anchor-certs-grouping' and 'end-entity-certs-
      grouping' (the plural form of existing groupings).

   o  Now states that keys created in <operational> by the *-hidden-key
      actions are bound to the lifetime of the parent 'config true'
      node, and that subsequent invocations of either action results in
      a failure.

A.8.  06 to 07

   o  Added clarifications that implementations SHOULD assert that
      configured certificates contain the matching public key.

   o  Replaced the 'generate-hidden-key' and 'install-hidden-key'
      actions with special 'crypt-hash' -like input/output values.

A.9.  07 to 08

   o  Removed the 'generate-key and 'hidden-key' features.

   o  Added grouping symmetric-key-grouping

   o  Modified 'asymmetric-key-pair-grouping' to have a 'choice'
      statement for the keystone module to augment into, as well as
      replacing the 'union' with leafs (having different NACM settings.

A.10.  08 to 09

   o  Converting algorithm from identities to enumerations.

A.11.  09 to 10

   o  All of the below changes are to the algorithm enumerations defined
      in ietf-crypto-types.

   o  Add in support for key exchange over x.25519 and x.448 based on
      RFC 8418.

   o  Add in SHAKE-128, SHAKE-224, SHAKE-256, SHAKE-384 and SHAKE 512




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   o  Revise/add in enum of signature algorithm for x25519 and x448

   o  Add in des3-cbc-sha1 for IPSec

   o  Add in sha1-des3-kd for IPSec

   o  Add in definit for rc4-hmac and rc4-hmac-exp.  These two
      algorithms have been deprecated in RFC 8429.  But some existing
      draft in i2nsf may still want to use them.

   o  Add x25519 and x448 curve for asymmetric algorithms

   o  Add signature algorithms ed25519, ed25519-cts, ed25519ph

   o  add signature algorithms ed448, ed448ph

   o  Add in rsa-sha2-256 and rsa-sha2-512 for SSH protocols (rfc8332)

A.12.  10 to 11

   o  Added a "key-format" identity.

   o  Added symmetric keys to the example in Section 2.3.

A.13.  11 to 12

   o  Removed all non-essential (to NC/RC) algorithm types.

   o  Moved remaining algorithm types each into its own module.

   o  Added a 'config false' "algorithms-supported" list to each of the
      algorithm-type modules.

Acknowledgements

   The authors would like to thank for following for lively discussions
   on list and in the halls (ordered by last name): Martin Bjorklund,
   Nick Hancock, Balazs Kovacs, Juergen Schoenwaelder, Eric Voit, and
   Liang Xia.

Authors' Addresses

   Kent Watsen
   Watsen Networks

   EMail: kent+ietf@watsen.net





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   Wang Haiguang
   Huawei

   EMail: wang.haiguang.shieldlab@huawei.com















































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