module ietf-keystore {

    yang-version 1.1;

    namespace
      "urn:ietf:params:xml:ns:yang:ietf-keystore";

    prefix ks;

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


    }
    import ietf-crypto-types {
      prefix ct;
      reference
        "RFC 9640: 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>
Author:   Kent Watsen <mailto:kent+ietf@watsen.net>";

    description
      "This module defines a 'keystore' to centralize management
of security credentials.

The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL',
'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED',
'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document
are to be interpreted as described in BCP 14 (RFC 2119)
(RFC 8174) when, and only when, they appear in all
capitals, as shown here.

Copyright (c) 2024 IETF Trust and the persons identified
as 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 9642
(https://www.rfc-editor.org/info/rfc9642); see the RFC
itself for full legal notices.";

    revision "2024-10-10" {
      description "Initial version";
      reference
        "RFC 9642: A YANG Data Model for a Keystore";

    }


    feature central-keystore-supported {
      description
        "The 'central-keystore-supported' feature indicates that
the server supports the central keystore (i.e., fully
implements the 'ietf-keystore' module).";
    }

    feature inline-definitions-supported {
      description
        "The 'inline-definitions-supported' feature indicates that
the server supports locally defined keys.";
    }

    feature asymmetric-keys {
      description
        "The 'asymmetric-keys' feature indicates that the server
implements the /keystore/asymmetric-keys subtree.";
    }

    feature symmetric-keys {
      description
        "The 'symmetric-keys' feature indicates that the server
implements the /keystore/symmetric-keys subtree.";
    }

    typedef central-symmetric-key-ref {
      type leafref {
        path "/ks:keystore/ks:symmetric-keys/ks:symmetric-key/ks:name";
      }
      description
        "This typedef enables modules to easily define a reference
to a symmetric key stored in the central keystore.";
    }

    typedef central-asymmetric-key-ref {
      type leafref {
        path "/ks:keystore/ks:asymmetric-keys/ks:asymmetric-key/ks:name";
      }
      description
        "This typedef enables modules to easily define a reference
to an asymmetric key stored in the central keystore.";
    }

    container keystore {
      nacm:default-deny-write;
      if-feature central-keystore-supported;
      description
        "A central keystore containing a list of symmetric keys and
a list of asymmetric keys.";
      container asymmetric-keys {
        nacm:default-deny-write;
        if-feature asymmetric-keys;
        description
          "A list of asymmetric keys.";
        list asymmetric-key {
          key "name";
          description "An asymmetric key.";
          leaf name {
            type string;
            description
              "An arbitrary name for the asymmetric key.";
          }

          leaf public-key-format {
            nacm:default-deny-write;
            type identityref {
              base public-key-format;
            }
            mandatory true;
            description
              "Identifies the public key's format.  Implementations SHOULD
ensure that the incoming public key value is encoded in the
specified format.";
          }

          leaf public-key {
            nacm:default-deny-write;
            type binary;
            mandatory true;
            description
              "The binary value of the public key.  The interpretation
of the value is defined by the 'public-key-format' field.";
          }

          leaf private-key-format {
            nacm:default-deny-write;
            type identityref {
              base private-key-format;
            }
            description
              "Identifies the private key's format.  Implementations SHOULD
ensure that the incoming private key value is encoded in the
specified format.

For encrypted keys, the value is the decrypted key's
format (i.e., the 'encrypted-value-format' conveys the
encrypted key's format).";
          }

          choice private-key-type {
            nacm:default-deny-write;
            mandatory true;
            description
              "Choice between key types.";
            case cleartext-private-key {
              if-feature cleartext-private-keys;
              leaf cleartext-private-key {
                nacm:default-deny-all;
                type binary;
                must "../private-key-format";
                description
                  "The value of the binary key.  The key's value is
interpreted by the 'private-key-format' field.";
              }
            }  // case cleartext-private-key

            case hidden-private-key {
              if-feature hidden-private-keys;
              leaf hidden-private-key {
                type empty;
                must
                  "not(../private-key-format)";
                description
                  "A hidden key.  It is of type 'empty' as its value is
inaccessible via management interfaces.  Though hidden
to users, such keys are not hidden to the server and
may be referenced by configuration to indicate which
key a server should use for a cryptographic operation.
How such keys are created is outside the scope of this
module.";
              }
            }  // case hidden-private-key

            case encrypted-private-key {
              if-feature encrypted-private-keys;
              container encrypted-private-key {
                must "../private-key-format";
                description
                  "A container for the encrypted asymmetric private key
value.  The interpretation of the 'encrypted-value'
node is via the 'private-key-format' node";
                container encrypted-by {
                  nacm:default-deny-write;
                  description
                    "An empty container enabling a reference to the key that
encrypted the value to be augmented in.  The referenced
key MUST be a symmetric key or an asymmetric key.

A symmetric key MUST be referenced via a leaf node called
'symmetric-key-ref'.  An asymmetric key MUST be referenced
via a leaf node called 'asymmetric-key-ref'.

The leaf nodes MUST be direct descendants in the data tree
and MAY be direct descendants in the schema tree (e.g.,
'choice'/'case' statements are allowed but not a
container).";
                  choice encrypted-by {
                    nacm:default-deny-write;
                    mandatory true;
                    description
                      "A choice amongst other symmetric or asymmetric keys.";
                    case central-symmetric-key-ref {
                      if-feature central-keystore-supported;
                      if-feature symmetric-keys;
                      leaf symmetric-key-ref {
                        type central-symmetric-key-ref;
                        description
                          "Identifies the symmetric key used to encrypt the
associated key.";
                      }
                    }  // case central-symmetric-key-ref

                    case central-asymmetric-key-ref {
                      if-feature central-keystore-supported;
                      if-feature asymmetric-keys;
                      leaf asymmetric-key-ref {
                        type central-asymmetric-key-ref;
                        description
                          "Identifies the asymmetric key whose public key
encrypted the associated key.";
                      }
                    }  // case central-asymmetric-key-ref
                  }  // choice encrypted-by
                }  // container encrypted-by

                leaf encrypted-value-format {
                  type identityref {
                    base encrypted-value-format;
                  }
                  mandatory true;
                  description
                    "Identifies the format of the 'encrypted-value' leaf.

If 'encrypted-by' points to a symmetric key, then an
identity based on 'symmetrically-encrypted-value-format'
MUST be set (e.g., 'cms-encrypted-data-format').

If 'encrypted-by' points to an asymmetric key, then an
identity based on 'asymmetrically-encrypted-value-format'
MUST be set (e.g., 'cms-enveloped-data-format').";
                }

                leaf encrypted-value {
                  nacm:default-deny-write;
                  type binary;
                  must "../encrypted-by";
                  mandatory true;
                  description
                    "The value, encrypted using the referenced symmetric
or asymmetric key.  The value MUST be encoded using
the format associated with the 'encrypted-value-format'
leaf.";
                }
              }  // container encrypted-private-key
            }  // case encrypted-private-key
          }  // choice private-key-type

          container certificates {
            nacm:default-deny-write;
            description
              "Certificates associated with this asymmetric key.";
            list certificate {
              key "name";
              description
                "A certificate for this asymmetric key.";
              leaf name {
                type string;
                description
                  "An arbitrary name for the certificate.";
              }

              leaf cert-data {
                nacm:default-deny-all;
                type end-entity-cert-cms;
                description
                  "The binary certificate data for this certificate.";
              }

              notification certificate-expiration {
                if-feature certificate-expiration-notification;
                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.

If the certificate's issuer maintains a Certificate
Revocation List (CRL), the expiration notification MAY
be sent if the CRL is about to expire.";
                leaf expiration-date {
                  type yang:date-and-time;
                  mandatory true;
                  description
                    "Identifies the expiration date on the certificate.";
                }
              }  // notification certificate-expiration
            }  // list certificate
          }  // container certificates

          action generate-csr {
            nacm:default-deny-all;
            if-feature csr-generation;
            description
              "Generates a certificate signing request structure for
the associated asymmetric key using the passed subject
and attribute values.

This 'action' statement is only available when the
associated 'public-key-format' node's value is
'subject-public-key-info-format'.";
            input {
              leaf csr-format {
                type identityref {
                  base csr-format;
                }
                mandatory true;
                description
                  "Specifies the format for the returned certificate.";
              }

              leaf csr-info {
                type csr-info;
                mandatory true;
                description
                  "A CertificationRequestInfo structure, as defined in
RFC 2986.

Enables the client to provide a fully populated
CertificationRequestInfo structure that the server
only needs to sign in order to generate the complete
CertificationRequest structure to return in the
'output'.

The 'AlgorithmIdentifier' field contained inside
the 'SubjectPublicKeyInfo' field MUST be one known
to be supported by the device.";
                reference
                  "RFC 2986:
                    PKCS #10: Certification Request Syntax Specification
                   RFC 9640:
                    YANG Data Types and Groupings for Cryptography";

              }
            }

            output {
              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.";
                case p10-csr {
                  description
                    "A CertificationRequest, as defined in RFC 2986.";
                  reference
                    "RFC 2986:
                      PKCS #10: Certification Request Syntax Specification
                     RFC 9640:
                      YANG Data Types and Groupings for Cryptography";

                  leaf p10-csr {
                    type p10-csr;
                    description
                      "A CertificationRequest, as defined in RFC 2986.";
                  }
                }  // case p10-csr
              }  // choice csr-type
            }
          }  // rpc generate-csr
        }  // list asymmetric-key
      }  // container asymmetric-keys

      container symmetric-keys {
        nacm:default-deny-write;
        if-feature symmetric-keys;
        description
          "A list of symmetric keys.";
        list symmetric-key {
          key "name";
          description "A symmetric key.";
          leaf name {
            type string;
            description
              "An arbitrary name for the symmetric key.";
          }

          leaf key-format {
            nacm:default-deny-write;
            type identityref {
              base symmetric-key-format;
            }
            description
              "Identifies the symmetric key's format.  Implementations
SHOULD ensure that the incoming symmetric key value is
encoded in the specified format.

For encrypted keys, the value is the decrypted key's
format (i.e., the 'encrypted-value-format' conveys the
encrypted key's format).";
          }

          choice key-type {
            nacm:default-deny-write;
            mandatory true;
            description
              "Choice between key types.";
            leaf cleartext-symmetric-key {
              nacm:default-deny-all;
              if-feature cleartext-symmetric-keys;
              type binary;
              must "../key-format";
              description
                "The binary value of the key.  The interpretation of
the value is defined by the 'key-format' field.";
            }

            case hidden-symmetric-key {
              if-feature hidden-symmetric-keys;
              leaf hidden-symmetric-key {
                type empty;
                must "not(../key-format)";
                description
                  "A hidden key is not exportable and not extractable;
therefore, it is of type 'empty' as its value is
inaccessible via management interfaces.  Though hidden
to users, such keys are not hidden to the server and
may be referenced by configuration to indicate which
key a server should use for a cryptographic operation.
How such keys are created is outside the scope of this
module.";
              }
            }  // case hidden-symmetric-key

            case encrypted-symmetric-key {
              if-feature encrypted-symmetric-keys;
              container encrypted-symmetric-key {
                must "../key-format";
                description
                  "A container for the encrypted symmetric key value.
The interpretation of the 'encrypted-value' node
is via the 'key-format' node";
                container encrypted-by {
                  nacm:default-deny-write;
                  description
                    "An empty container enabling a reference to the key that
encrypted the value to be augmented in.  The referenced
key MUST be a symmetric key or an asymmetric key.

A symmetric key MUST be referenced via a leaf node called
'symmetric-key-ref'.  An asymmetric key MUST be referenced
via a leaf node called 'asymmetric-key-ref'.

The leaf nodes MUST be direct descendants in the data tree
and MAY be direct descendants in the schema tree (e.g.,
'choice'/'case' statements are allowed but not a
container).";
                  choice encrypted-by {
                    nacm:default-deny-write;
                    mandatory true;
                    description
                      "A choice amongst other symmetric or asymmetric keys.";
                    case central-symmetric-key-ref {
                      if-feature central-keystore-supported;
                      if-feature symmetric-keys;
                      leaf symmetric-key-ref {
                        type central-symmetric-key-ref;
                        description
                          "Identifies the symmetric key used to encrypt the
associated key.";
                      }
                    }  // case central-symmetric-key-ref

                    case central-asymmetric-key-ref {
                      if-feature central-keystore-supported;
                      if-feature asymmetric-keys;
                      leaf asymmetric-key-ref {
                        type central-asymmetric-key-ref;
                        description
                          "Identifies the asymmetric key whose public key
encrypted the associated key.";
                      }
                    }  // case central-asymmetric-key-ref
                  }  // choice encrypted-by
                }  // container encrypted-by

                leaf encrypted-value-format {
                  type identityref {
                    base encrypted-value-format;
                  }
                  mandatory true;
                  description
                    "Identifies the format of the 'encrypted-value' leaf.

If 'encrypted-by' points to a symmetric key, then an
identity based on 'symmetrically-encrypted-value-format'
MUST be set (e.g., 'cms-encrypted-data-format').

If 'encrypted-by' points to an asymmetric key, then an
identity based on 'asymmetrically-encrypted-value-format'
MUST be set (e.g., 'cms-enveloped-data-format').";
                }

                leaf encrypted-value {
                  nacm:default-deny-write;
                  type binary;
                  must "../encrypted-by";
                  mandatory true;
                  description
                    "The value, encrypted using the referenced symmetric
or asymmetric key.  The value MUST be encoded using
the format associated with the 'encrypted-value-format'
leaf.";
                }
              }  // container encrypted-symmetric-key
            }  // case encrypted-symmetric-key
          }  // choice key-type
        }  // list symmetric-key
      }  // container symmetric-keys
    }  // container keystore
  }  // module ietf-keystore