module ietf-ztp-types {

    yang-version 1.1;

    namespace
      "urn:ietf:params:xml:ns:yang:ietf-ztp-types";

    prefix zt;

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


    }

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

    contact
      "WG Web:   https://datatracker.ietf.org/wg/netconf
     WG List:  NETCONF WG list <mailto:netconf@ietf.org>
     Authors:  Kent Watsen <mailto:kent+ietf@watsen.net>
               Russ Housley <mailto:housley@vigilsec.com>
               Sean Turner <mailto:sean@sn3rd.com>";

    description
      "This module defines three groupings that enable
     bootstrapping devices to 1) indicate if and how they
     support generating CSRs, 2) obtain a request to
     generate a CSR, and 3) communicate the requested CSR.

     Copyright (c) 2022 IETF Trust and the persons identified
     as authors of the code. All rights reserved.

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

     This version of this YANG module is part of RFC 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 "2022-01-31" {
      description "Initial version";
      reference
        "RFC XXXX: Conveying a Certificate Signing Request (CSR)
        	  in a Secure Zero Touch Provisioning (SZTP)
        	  Bootstrapping Request";

    }


    identity certificate-request-format {
      description
        "A base identity for the request formats supported
       by the ZTP-client.

       Additional derived identities MAY be defined by
       future efforts.";
    }

    identity p10-csr {
      base certificate-request-format;
      description
        "Indicates that the ZTP-client supports generating
       requests using the 'CertificationRequest' structure
       defined in RFC 2986.";
      reference
        "RFC 2986: PKCS #10: Certification Request Syntax
        	  Specification Version 1.7";

    }

    identity cmp-csr {
      base certificate-request-format;
      description
        "Indicates that the ZTP-client supports generating
       requests using a profiled version of the PKIMessage
       that MUST contain a PKIHeader followed by a PKIBody
       containing only the p10cr structure defined in
       RFC 4210.";
      reference
        "RFC 4210: Internet X.509 Public Key Infrastructure
        	  Certificate Management Protocol (CMP)";

    }

    identity cmc-csr {
      base certificate-request-format;
      description
        "Indicates that the ZTP-client supports generating
       requests using a profiled version of the 'Full
       PKI Request' structure defined in RFC 5272.";
      reference
        "RFC 5272: Certificate Management over CMS (CMC)";

    }

    grouping csr-support-grouping {
      description
        "A grouping enabling use by other efforts.";
      container csr-support {
        description
          "Enables a ZTP-client to indicate that it supports
       generating certificate signing requests (CSRs) and
       provides details about the CSRs it is able to
       generate.";
        container key-generation {
          presence
            "Indicates that the ZTP-client is capable of
           generating a new asymmetric key pair.

           If this node is not present, the ZTP-server MAY
           request a CSR using the asymmetric key associated
           with the device's existing identity certificate
           (e.g., an IDevID from IEEE 802.1AR).";
          description
            "Specifies details for the ZTP-client's ability to
           generate a new asymmetric key pair.";
          container supported-algorithms {
            description
              "A list of public key algorithms supported by the
             ZTP-client for generating a new asymmetric key.";
            leaf-list algorithm-identifier {
              type binary;
              min-elements 1;
              description
                "An AlgorithmIdentifier, as defined in RFC 2986,
               encoded using ASN.1 distinguished encoding rules
               (DER), as specified in ITU-T X.690.";
              reference
                "RFC 2986: PKCS #10: Certification Request Syntax
                	  Specification Version 1.7
                ITU-T X.690:
                  Information technology - ASN.1 encoding rules:
                  Specification of Basic Encoding Rules (BER),
                  Canonical Encoding Rules (CER) and Distinguished
                  Encoding Rules (DER).";

            }
          }  // container supported-algorithms
        }  // container key-generation

        container csr-generation {
          description
            "Specifies details for the ZTP-client's ability to
           generate a certificate signing requests.";
          container supported-formats {
            description
              "A list of certificate request formats supported
             by the ZTP-client for generating a new key.";
            leaf-list format-identifier {
              type identityref {
                base zt:certificate-request-format;
              }
              min-elements 1;
              description
                "A certificate request format supported by the
               ZTP-client.";
            }
          }  // container supported-formats
        }  // container csr-generation
      }  // container csr-support
    }  // grouping csr-support-grouping

    grouping csr-request-grouping {
      description
        "A grouping enabling use by other efforts.";
      container key-generation {
        presence
          "Provided by a ZTP-server to indicate that it wishes
         the ZTP-client to generate a new asymmetric key.

         This statement is present so the mandatory descendant
         nodes do not imply that this node must be configured.";
        description
          "The key generation parameters selected by the ZTP-server.

         This leaf MUST only appear if the ZTP-client's
         'csr-support' included the 'key-generation' node.";
        container selected-algorithm {
          description
            "The key algorithm selected by the ZTP-server. The
           algorithm MUST be one of the algorithms specified by
           the 'supported-algorithms' node in the ZTP-client's
           message containing the 'csr-support' structure.";
          leaf algorithm-identifier {
            type binary;
            mandatory true;
            description
              "An AlgorithmIdentifier, as defined in RFC 2986,
             encoded using ASN.1 distinguished encoding rules
             (DER), as specified in ITU-T X.690.";
            reference
              "RFC 2986: PKCS #10: Certification Request Syntax
              	  Specification Version 1.7
              ITU-T X.690:
                Information technology - ASN.1 encoding rules:
                Specification of Basic Encoding Rules (BER),
                Canonical Encoding Rules (CER) and Distinguished
                Encoding Rules (DER).";

          }
        }  // container selected-algorithm
      }  // container key-generation

      container csr-generation {
        description
          "Specifies details for the CSR that the ZTP-client
         is to generate.";
        container selected-format {
          description
            "The CSR format selected by the ZTP-server. The
           format MUST be one of the formats specified by
           the 'supported-formats' node in the ZTP-client's
           request message.";
          leaf format-identifier {
            type identityref {
              base zt:certificate-request-format;
            }
            mandatory true;
            description
              "A certificate request format to be used by the
             ZTP-client.";
          }
        }  // container selected-format
      }  // container csr-generation

      leaf cert-req-info {
        type ct:csr-info;
        description
          "A CertificationRequestInfo structure, as defined in
         RFC 2986, and modeled via a 'typedef' statement by
         RFC AAAA.

         Enables the ZTP-server to provide a fully-populated
         CertificationRequestInfo structure that the ZTP-client
         only needs to sign in order to generate the complete
         'CertificationRequest' structure to send to ZTP-server
         in its next 'get-bootstrapping-data' request message.

         When provided, the ZTP-client MUST use this structure
         to generate its CSR; failure to do so will result in a
         400 Bad Request response containing another 'csr-request'
         structure.

         When not provided, the ZTP-client SHOULD generate a CSR
         using the same structure defined in its existing identity
         certificate (e.g., an IDevID from IEEE 802.1AR).

         If the 'AlgorithmIdentifier' field contained inside the
         certificate 'SubjectPublicKeyInfo' field does not match
         the algorithm identified by the 'selected-algorithm' node,
         then the client MUST reject the certificate and raise an
         error.";
        reference
          "RFC 2986:
            PKCS #10: Certification Request Syntax Specification
          RFC AAAA:
            YANG Data Types and Groupings for Cryptography";

      }
    }  // grouping csr-request-grouping

    grouping csr-grouping {
      description
        "Enables a ZTP-client to convey a certificate signing
       request, using the encoding format selected by a
       ZTP-server's 'csr-request' response to the ZTP-client's
       previously sent request containing the 'csr-support'
       node.";
      choice csr-type {
        mandatory true;
        description
          "A choice amongst certificate signing request formats.

         Additional formats MAY be augmented into this 'choice'
         statement by future efforts.";
        leaf p10-csr {
          type ct:csr;
          description
            "A CertificationRequest structure, per RFC 2986.
             Encoding details are defined in the 'ct:csr'
             typedef defined in RFC AAAA.

             A raw P10 does not support origin authentication in
             the CSR structure.  External origin authentication
             may be provided via the ZTP-client's authentication
             to the ZTP-server at the transport layer (e.g., TLS).";
          reference
            "RFC 2986: PKCS #10: Certification Request Syntax
            	  Specification
            RFC AAAA: YANG Data Types and Groupings for
            	  Cryptography";

        }
        leaf cmc-csr {
          type binary;
          description
            "A profiled version of the 'Full PKI Request'
             message defined in RFC 5272, encoded using ASN.1
             distinguished encoding rules (DER), as specified
             in ITU-T X.690.

             For asymmetric key-based origin authentication of a
             CSR based on the initial device identity certificate's
             private key for the associated identity certificate's
             public key, the PKIData contains one reqSequence
             element and no cmsSequence or otherMsgSequence
             elements. The reqSequence is the TaggedRequest
             and it is the tcr CHOICE branch. The tcr is the
             TaggedCertificationRequest and it is the bodyPartId
             and the certificateRequest elements.  The
             certificateRequest is signed with the initial device
             identity certificate's private key. The initial device
             identity certificate and optionally its certificate
             chain is included in the SignedData certificates that
             encapsulates the PKIData.

             For asymmetric key-based origin authentication based on
             the initial device identity certificate's private key
             that signs the encapsulated CSR signed by the local
             device identity certificate's private key, the
             PKIData contains one cmsSequence element and no
             reqSequence or otherMsgSequence
             elements.  The cmsSequence is the TaggedContentInfo
             and it includes a bodyPartID element and a contentInfo.
             The contentInfo is a SignedData encapsulating a PKIData
             with one reqSequence element and no cmsSequence or
             otherMsgSequence elements. The reqSequence is the
             TaggedRequest and it is the tcr CHOICE. The tcr is the
             TaggedCertificationRequest and it is the bodyPartId and
             the certificateRequest elements.  PKIData contains one
             cmsSequence element and no controlSequence, reqSequence,
             or otherMsgSequence elements.  The certificateRequest
             is signed with the local device identity certificate's
             private key.  The initial device identity certificate
             and optionally its certificate chain is included in the
             SignedData certificates that encapsulates the PKIData.

             For shared secret-based origin authentication of a
             CSR signed by the local device identity certificate's
             private key, the PKIData contains one cmsSequence
             element and no reqSequence or otherMsgSequence
             elements. The cmsSequence is the TaggedContentInfo
             and it includes a bodyPartID element and a contentInfo.
             The contentInfo is an AuthenticatedData encapsulating
             a PKIData with one reqSequence element and no
             cmsSequences or otherMsgSequence elements. The
             reqSequence is the TaggedRequest and it is the tcr
             CHOICE. The tcr is the TaggedCertificationRequest
             and it is the bodyPartId and the certificateRequest
             elements.  The certificateRequest is signed with the
             local device identity certificate's private key. The
             initial device identity certificate and optionally its
             certificate chain is included in the SignedData
             certificates that encapsulates the PKIData.";
          reference
            "RFC 5272: Certificate Management over CMS (CMC)
            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 cmp-csr {
          type binary;
          description
            "A PKIMessage structure, as defined in RFC 4210,
             encoded using ASN.1 distinguished encoding rules
             (DER), as specified in ITU-T X.690.

             For asymmetric key-based origin authentication of a
             CSR based on the initial device identity certificate's
             private key for the associated initial device identity
             certificate's public key, PKIMessages contains one
             PKIMessage with the header and body elements, no
             protection element, and SHOULD contain the extraCerts
             element. The header element contains the pvno, sender,
             and recipient elements. The pvno contains cmp2000, and
             the sender contains the subject of the initial device
             identity certificate. The body element contains a p10cr
             CHOICE of type CertificationRequest.  It is signed with
             the initial device identity certificate's private key.
             The extraCerts element contains the initial device
             identity certificate, optionally followed by its
             certificate chain excluding the trust anchor.

             For asymmetric key-based origin authentication based on
             the initial device identity certificate's private key
             that signs the encapsulated CSR signed by the local
             device identity certificate's private key, PKIMessages
             contains one PKIMessage with the header, body, and
             protection elements, and SHOULD contain the extraCerts
             element. The header element contains the pvno, sender,
             recipient, protectionAlg, and optionally senderKID
             elements. The pvno contains cmp2000, the sender
             contains the subject of the initial device identity
             certificate, the protectionAlg contains the
             AlgorithmIdentifier of the used signature algorithm,
             and the senderKID contains the subject key identifier
             of the initial device identity certificate. The
             body element contains a p10cr CHOICE of type
             CertificationRequest. It is signed with the local device
             identity certificate's private key.  The protection
             element contains the digital signature generated with
             the initial device identity certificate's private key.
             The extraCerts element contains the initial device
             identity certificate, optionally followed by its
             certificate chain excluding the trust anchor.

             For shared secret-based origin authentication of a
             CSR signed by the local device identity certificate's
             private key, PKIMessages contains one PKIMessage with
             the header, body, and protection element, and no
             extraCerts element. The header element contains the
             pvno, sender, recipient, protectionAlg, and senderKID
             elements. The pvno contains cmp2000, the protectionAlg
             contains the AlgorithmIdentifier of the used MAC
             algorithm, and the senderKID contains a reference
             the recipient can use to identify the shared secret.
             The body element contains a p10cr CHOICE of type
             CertificationRequest. It is signed with the local
             device identity certificate's private key.  The
             protection element contains the MAC value generated
             with the shared secret.";
          reference
            "RFC 4210:
              Internet X.509 Public Key Infrastructure
              Certificate Management Protocol (CMP)
            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).";

        }
      }  // choice csr-type
    }  // grouping csr-grouping
  }  // module ietf-ztp-types