module kea-dhcp4-server {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:kea-dhcp4-server";
  prefix "kea-dhcp4-server";

  import ietf-inet-types {
    prefix inet;
  }
  import kea-types {
    prefix kea;
    revision-date 2019-08-12;
  }
  import kea-dhcp-types {
    prefix dhcp;
    revision-date 2023-06-28;
  }

  organization "Internet Systems Consortium";
  contact "kea-dev@lists.isc.org";
  description "This model defines a YANG data model that can be
               used to configure and manage a Kea DHCPv4 server.";

  revision 2023-06-28 {
    description "Added pool ID.";
  }

  revision 2023-05-31 {
    description "Added allocator, ddns-ttl-percent, exclude-first-last-24,
                 ignore-dhcp-server-identifier, offer-lifetime,
                 read-timeout, tcp-user-timeout, write-timeout.
                 Removed contact-points, keyspace.";
  }

  revision 2022-12-27 {
    description "Added never-send to option-data.";
  }

  revision 2022-11-30 {
    description "Added the template-test node for client classes.";
  }

  revision 2022-07-27 {
    description "Added TLS parameters for database connections: trust-anchor,
                 cert-file, key-file, cipher-list. Added parameters which govern
                 the way the server behaves regarding detection of configured
                 interfaces: service-sockets-require-all,
                 service-sockets-max-retries, service-sockets-retry-wait-time.
                 Added parameters which govern reservations lookup:
                 early-global-reservations-lookup, reservations-lookup-first.";
  }

  revision 2021-11-24 {
    description "Fixed store-extended-info. Added several containers and leaves:
                 compatibility, lenient-option-parsing, multi-threading,
                 enable-multi-threading, packet-queue-size, thread-pool-size,
                 valid-lifetime, min-valid-lifetime, max-valid-lifetime,
                 preferred-lifetime, min-preferred-lifetime,
                 max-preferred-lifetime, cache-max-age, cache-threshold,
                 ddns-generated-prefix, ddns-override-client-update,
                 ddns-override-no-update, ddns-qualifying-suffix,
                 ddns-replace-client-name, ddns-send-updates,
                 ddns-update-on-renew, ddns-use-conflict-resolution,
                 ip-reservations-unique, parked-packet-limit,
                 reservations-global, reservations-in-subnet,
                 reservations-out-of-pool, statistic-default-sample-age,
                 statistic-default-sample-count, store-extended-info, on-fail.";
  }

  revision 2021-08-25 {
    description "Added store-extended-info";
  }

  revision 2019-08-12 {
    description "Initial revision";
  }

  /*
  * Typedefs
  */
  typedef host-identifier-type {
    type enumeration {
      enum "duid" {
        description "DUID";
      }
      enum "hw-address" {
        description "Hardware address";
      }
      enum "circuit-id" {
        description "Circuit-id option";
      }
      enum "client-id" {
        description "Client identifier";
      }
      enum "flex-id" {
        description "Flexible identifier";
      }
    }
    description "Host identifier type.";
  }

  /*
  * Groupings
  */
  grouping match-client-id {
    description "Match client ID grouping.";
    leaf match-client-id {
      type boolean;
      description "Use client-id for lease lookups. If set to false, client-id
                   will be ignored.";
    }
  }

  grouping next-server {
    description "Next server address grouping.";
    leaf next-server {
      type inet:ipv4-address;
      description "Next server IPv4 address. If set, this value will be set
                   in siaddr field.";
    }
  }

  grouping server-hostname {
    description "Server hostname grouping.";
    leaf server-hostname {
      type string;
      description "Server hostname (up to 64 bytes).";
    }
  }

  grouping boot-file-name {
    description "Boot file name grouping.";
    leaf boot-file-name {
      type string;
      description "Boot file name (up to 128 bytes).";
    }
  }

  grouping authoritative {
    description "Authoritative grouping.";
    leaf authoritative {
      type boolean;
      description "NAK requests for unknown clients. If set to false
                   ignore them.";
      }
  }

  grouping relay {
    description "Relay grouping.";
    leaf-list ip-addresses {
      type inet:ipv4-address;
      description "IPv4 addresses.";
    }
  }

  grouping host {
    description "Host grouping.";
    leaf identifier-type {
      type host-identifier-type;
      mandatory true;
      description "Host identifier type.";
    }
    uses dhcp:host-identifier;
    leaf ip-address {
      type inet:ipv4-address;
      description "Host reserved IPv4 address.";
    }
    uses dhcp:host-hostname;
    uses dhcp:host-client-classes;
    uses option-data-list;
    uses next-server;
    uses server-hostname;
    uses boot-file-name;
    uses dhcp:host-user-context;
  }

  grouping reservations {
    description "Host reservations grouping.";
    list host {
      key "identifier-type identifier";
      description "Host reservation list.";
      uses host;
    }
  }

  grouping subnet4-list {
    description "Subnet4 list grouping.";
    list subnet4 {
      key id;
      ordered-by user;
      description "List of IPv4 subnets.";
      uses dhcp:allocator;
      uses dhcp:offer-lifetime;
      uses dhcp:valid-lifetime;
      uses dhcp:min-valid-lifetime;
      uses dhcp:max-valid-lifetime;
      uses dhcp:renew-timer;
      uses dhcp:rebind-timer;
      uses dhcp:calculate-tee-times;
      uses dhcp:t1-percent;
      uses dhcp:t2-percent;
      uses option-data-list;
      list pool {
        key "start-address end-address";
        ordered-by user;
        description "Pool list.";
        leaf prefix {
          type inet:ipv4-prefix;
          description "Defines a pool of dynamic IPv4 addresses to be managed
                       by the server.";
        }
        leaf start-address {
          type inet:ipv4-address;
          mandatory true;
          description "First IPv4 address in a pool.";
        }
        leaf end-address {
          type inet:ipv4-address;
          mandatory true;
          description "Last IPv4 address in a pool.";
        }
        uses option-data-list;
        uses dhcp:pool-client-class;
        uses dhcp:pool-require-client-classes;
        uses dhcp:pool-id;
        uses dhcp:pool-user-context;
      }
      leaf subnet {
        type inet:ipv4-prefix;
        mandatory true;
        description "IPv4 subnet prefix.";
      }
      uses dhcp:subnet-interface;
      uses dhcp:subnet-id;
      uses dhcp:subnet-client-class;
      uses dhcp:subnet-require-client-classes;
      uses reservations {
        refine host {
          description "Subnet host reservations list.";
        }
      }
      uses dhcp:reservation-mode;
      container relay {
        description "Optional information about relay agent.";
        uses relay;
      }
      uses match-client-id;
      uses next-server;
      uses server-hostname;
      uses boot-file-name;
      leaf subnet-4o6-interface {
        type string;
        description "Subnet DHCPv4-over-DHCPv6 interface.";
      }
      leaf subnet-4o6-interface-id {
        type string;
        description "Subnet DHCPv4-over-DHCPv6 interface-id option.";
      }
      leaf subnet-4o6-subnet {
        type inet:ipv6-prefix;
        description "Subnet DHCPv4-over-DHCPv6 IPv6 prefix.";
      }
      uses authoritative;
      uses dhcp:cache-max-age;
      uses dhcp:cache-threshold;
      uses dhcp:ddns-generated-prefix;
      uses dhcp:ddns-override-client-update;
      uses dhcp:ddns-override-no-update;
      uses dhcp:ddns-qualifying-suffix;
      uses dhcp:ddns-replace-client-name;
      uses dhcp:ddns-send-updates;
      uses dhcp:ddns-ttl-percent;
      uses dhcp:ddns-update-on-renew;
      uses dhcp:ddns-use-conflict-resolution;
      uses dhcp:hostname-char-replacement;
      uses dhcp:hostname-char-set;
      uses dhcp:reservations-global;
      uses dhcp:reservations-in-subnet;
      uses dhcp:reservations-out-of-pool;
      uses dhcp:store-extended-info;
      uses dhcp:subnet-user-context;
    }
  }

  grouping client-classes {
    description "Client class grouping.";
    list client-class {
      key name;
      ordered-by user;
      description "List of client classes.";
      uses dhcp:class-name;
      uses dhcp:class-test;
      uses dhcp:template-test;
      uses dhcp:class-only-if-required;
      uses dhcp:offer-lifetime;
      uses option-def-list;
      uses option-data-list;
      uses next-server;
      uses server-hostname;
      uses boot-file-name;
      uses dhcp:valid-lifetime;
      uses dhcp:min-valid-lifetime;
      uses dhcp:max-valid-lifetime;
      uses dhcp:class-user-context;
    }
  }

  grouping option-def-list {
    description "Option definition list grouping.";
    list option-def {
      key "code space";
      description "Option definition entry.";
      leaf code {
        type uint8;
        mandatory true;
        description "Option code to be used by the new option definition.";
      }
      leaf space {
        type string;
        mandatory true;
        description "Option space for the new option (typically dhcp4).";
      }
      uses dhcp:option-def-name;
      uses dhcp:option-def-type;
      uses dhcp:option-def-record-types;
      uses dhcp:option-def-encapsulate;
      uses dhcp:option-def-array;
      uses dhcp:option-def-user-context;
     }
  }

  grouping option-data-list {
    description "Option data list grouping.";
    list option-data {
      key "code space";
      description "Option data entry.";
      leaf code {
        type uint8;
        mandatory true;
        description "Option code.";
      }
      leaf space {
        type string;
        mandatory true;
        description "Option space.";
      }
      uses dhcp:option-data-name;
      uses dhcp:option-data-data;
      uses dhcp:option-data-csv-format;
      uses dhcp:option-data-always-send;
      uses dhcp:option-data-never-send;
      uses dhcp:option-data-user-context;
    }
  }

  /*
  * Data Nodes
  */

  container config {
    // config true;
    description "Contains DHCPv4 server configuration.";

    uses dhcp:allocator;
    uses dhcp:offer-lifetime;
    uses dhcp:valid-lifetime;
    uses dhcp:min-valid-lifetime;
    uses dhcp:max-valid-lifetime;
    uses dhcp:renew-timer;
    uses dhcp:rebind-timer;
    uses dhcp:calculate-tee-times;
    uses dhcp:t1-percent;
    uses dhcp:t2-percent;
    uses dhcp:decline-probation-period;
    uses subnet4-list;

    list shared-network {
      key name;
      description "List of IPv4 shared networks.";
      uses dhcp:network-name;
      uses subnet4-list;
      uses dhcp:allocator;
      uses dhcp:offer-lifetime;
      uses dhcp:network-interface;
      uses dhcp:renew-timer;
      uses dhcp:rebind-timer;
      uses option-data-list;
      uses match-client-id;
      uses next-server;
      uses server-hostname;
      uses boot-file-name;
      container relay {
        description "Optional information about relay agent.";
        uses relay;
      }
      uses authoritative;
      uses dhcp:reservation-mode;
      uses dhcp:network-client-class;
      uses dhcp:network-require-client-classes;
      uses dhcp:valid-lifetime;
      uses dhcp:min-valid-lifetime;
      uses dhcp:max-valid-lifetime;
      uses dhcp:calculate-tee-times;
      uses dhcp:t1-percent;
      uses dhcp:t2-percent;
      uses dhcp:cache-max-age;
      uses dhcp:cache-threshold;
      uses dhcp:ddns-generated-prefix;
      uses dhcp:ddns-override-client-update;
      uses dhcp:ddns-override-no-update;
      uses dhcp:ddns-qualifying-suffix;
      uses dhcp:ddns-replace-client-name;
      uses dhcp:ddns-send-updates;
      uses dhcp:ddns-ttl-percent;
      uses dhcp:ddns-update-on-renew;
      uses dhcp:ddns-use-conflict-resolution;
      uses dhcp:hostname-char-replacement;
      uses dhcp:hostname-char-set;
      uses dhcp:reservations-global;
      uses dhcp:reservations-in-subnet;
      uses dhcp:reservations-out-of-pool;
      uses dhcp:store-extended-info;
      uses dhcp:network-user-context;
    }

    container interfaces-config {
      description "Network interfaces configuration.";
      leaf-list interfaces {
        type string;
        description "Name of the interface (e.g. eth0) or name/address
                     (e.g. eth0/192.168.1.1) or * (use all interfaces).";
      }
      leaf dhcp-socket-type {
        type enumeration {
          enum "raw" {
            description "DHCP service uses RAW sockets.";
          }
          enum "udp" {
            description "DHCP service uses UDP sockets.";
          }
        }
        description "Type of sockets to use.";
      }
      leaf outbound-interface {
        type enumeration {
          enum "same-as-inbound" {
            description "Send the response on the interface where the query
                         was received.";
          }
          enum "use-routing" {
            description "Use kernel routing.";
          }
        }
        description "Control the interface used to send a response.";
      }
      uses dhcp:interfaces-re-detect;
      uses dhcp:interfaces-service-sockets-require-all;
      uses dhcp:interfaces-service-sockets-max-retries;
      uses dhcp:interfaces-service-sockets-retry-wait-time;
      uses dhcp:interfaces-user-context;
    }

    uses dhcp:databases;

    leaf-list host-reservation-identifiers {
      type host-identifier-type;
      description "Host reservation identifiers.";
    }

    uses client-classes;
    uses option-def-list;
    uses option-data-list;
    uses kea:hooks-libraries;
    uses dhcp:expired-leases-processing;
    uses dhcp:dhcp4o6-port;
    uses kea:control-socket;
    uses dhcp:hostname-char-set;
    uses dhcp:hostname-char-replacement;
    uses dhcp:dhcp-ddns;

    leaf echo-client-id {
      type boolean;
      description "Send client-id back when the client sent it. This
                   is conformant with RFC6842, but some older, buggy
                   clients have problems with it.";
    }

    uses match-client-id;
    uses next-server;
    uses server-hostname;
    uses boot-file-name;
    uses authoritative;
    uses kea:user-context {
      refine user-context {
        description "DHCPv4 server user context. Arbitrary JSON data can
                     be stored here.";
      }
    }
    uses dhcp:sanity-checks;
    uses dhcp:reservation-mode;
    uses reservations {
      refine host {
        description "Global host reservations list.";
      }
    }
    uses dhcp:config-control;
    uses dhcp:server-tag;
    uses dhcp:dhcp-queue-control;
    uses kea:loggers;
    uses dhcp:cache-max-age;
    uses dhcp:cache-threshold;
    container compatibility {
      uses dhcp:common-compatibility;
      uses dhcp:v4-compatibility;
    }
    uses dhcp:ddns-generated-prefix;
    uses dhcp:ddns-override-client-update;
    uses dhcp:ddns-override-no-update;
    uses dhcp:ddns-qualifying-suffix;
    uses dhcp:ddns-replace-client-name;
    uses dhcp:ddns-send-updates;
    uses dhcp:ddns-ttl-percent;
    uses dhcp:ddns-update-on-renew;
    uses dhcp:ddns-use-conflict-resolution;
    uses dhcp:ip-reservations-unique;
    uses dhcp:early-global-reservations-lookup;
    uses dhcp:reservations-lookup-first;
    uses dhcp:multi-threading;
    uses dhcp:parked-packet-limit;
    uses dhcp:reservations-global;
    uses dhcp:reservations-in-subnet;
    uses dhcp:reservations-out-of-pool;
    uses dhcp:statistic-default-sample-age;
    uses dhcp:statistic-default-sample-count;
    uses dhcp:store-extended-info;
  }

  /*
  * State data
  */
  container state {
    config false;
    description "State of Kea DHCPv4 server.";

    container leases {
      description "Kea DHCPv4 leases.";
      list lease {
        key ip-address;
        description "List of Kea DHCPv4 leases.";
        leaf ip-address {
          type inet:ipv4-address;
          mandatory true;
          description "Lease IP address.";
        }
        leaf hw-address {
          type binary;
          mandatory true;
          description "Lease hardware address.";
        }
        leaf client-id {
          type binary;
          description "Lease client-id.";
        }
        uses dhcp:valid-lifetime {
          refine valid-lifetime {
            mandatory true;
          }
        }
        leaf cltt {
          type uint32;
          units "seconds";
          mandatory true;
          description "Lease client last transmission time.";
        }
        leaf subnet-id {
          type uint32;
          mandatory true;
          description "Lease subnet ID.";
        }
        leaf fqdn-fwd {
          type boolean;
          description "Lease FQDN forward flag.";
        }
        leaf fqdn-rev {
          type boolean;
          description "Lease FQDN reverse lag.";
        }
        leaf hostname {
          type string;
          description "Lease hostname.";
        }
        leaf state {
          type dhcp:lease-state;
          description "Lease state.";
        }
        leaf user-context {
          type kea:user-context;
          description "Lease user context.";
        }
      }
    }

    container lease-stats {
      description "Lease statistics.";
      list subnet {
        key subnet-id;
        description "List of IPv4 subnets.";
        leaf subnet-id {
          type uint32;
          mandatory true;
          description "Subnet ID.";
        }
        leaf total-addresses {
          type uint32;
          mandatory true;
          description "Total addresses counter.";
        }
        leaf assigned-addresses {
          type uint32;
          mandatory true;
          description "Assigned addresses counter.";
        }
        leaf declined-addresses {
          type uint32;
          mandatory true;
          description "Declined addresses counter.";
        }
      }
    }

    container hosts {
      description "Kea DHCPv4 hosts.";
      list host {
        key "subnet-id identifier-type identifier";
        description "List of Kea DHCPv4 hosts.";
        uses host;
        uses dhcp:host-subnet-id;
        leaf auth-key {
          type string;
          description "Host authentication key (unused in DHCPv4).";
        }
      }
    }
  }
}