module bbf-l2-dhcpv4-relay {

    yang-version 1.1;

    namespace
      "urn:bbf:yang:bbf-l2-dhcpv4-relay";

    prefix bbf-l2-d4r;

    import ietf-interfaces {
      prefix if;
    }
    import ietf-yang-types {
      prefix yang;
    }
    import bbf-yang-types {
      prefix bbf-yang;
    }
    import bbf-if-type {
      prefix bbfift;
    }
    import bbf-subscriber-types {
      prefix bbf-subtype;
    }

    organization
      "Broadband Forum <https://www.broadband-forum.org>
     Common YANG Work Area";

    contact
      "Comments or questions about this Broadband Forum YANG module
     should be directed to <mailto:help@broadband-forum.org>.

     Editor:      Nick Hancock, ADTRAN

     Editor:      Ludwig Pauwels, Nokia

     PS Leader:   Joey Boyd, ADTRAN

     WA Director: Joey Boyd, ADTRAN

     WA Director: Sven Ooghe, Nokia";

    description
      "This module contains a collection of YANG definitions for
     supporting the Broadband Forum requirements on subscriber
     management via the DHCPv4 protocol as applicable to access
     network equipment. As such, this module is specific to access
     network equipment (e.g., BBF-specified Access Nodes and FTTdp
     DPUs).

     Copyright (c) 2017-2022, Broadband Forum

     Redistribution and use in source and binary forms, with or
     without modification, are permitted provided that the following
     conditions are met:

     1. Redistributions of source code must retain the above copyright
        notice, this list of conditions and the following disclaimer.

     2. Redistributions in binary form must reproduce the above
        copyright notice, this list of conditions and the following
        disclaimer in the documentation and/or other materials
        provided with the distribution.

     3. Neither the name of the copyright holder nor the names of its
        contributors may be used to endorse or promote products
        derived from this software without specific prior written
        permission.

     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
     CONTRIBUTORS \"AS IS\" AND ANY EXPRESS OR IMPLIED WARRANTIES,
     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
     CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
     STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
     ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

     The above license is used as a license under copyright only.
     Please reference the Forum IPR Policy for patent licensing terms
     <https://www.broadband-forum.org/ipr-policy>.

     Any moral rights which are necessary to exercise under the above
     license grant are also deemed granted under this license.

     This version of this YANG module is part of TR-383a5; see
     the TR itself for full legal notices.";

    revision "2022-03-01" {
      description
        "Amendment 5.
       * Approval Date:    2022-03-01.
       * Publication Date: 2022-03-01.";
      reference
        "TR-383a5: Common YANG Modules
        	  <https://www.broadband-forum.org/technical/download/
        		   TR-383_Amendment-5.pdf>";

    }

    revision "2017-05-08" {
      description
        "Initial revision.
       * Approval Date:    see revision date above.
       * Publication Date: 2017-06-02.";
      reference
        "TR-383: Common YANG Modules
        	<https://www.broadband-forum.org/technical/download/
        		 TR-383.pdf>";

    }


    augment /if:interfaces/if:interface {
      when
        "derived-from-or-self(if:type,
                               'bbfift:vlan-sub-interface')" {
        description
          "Applies only to VLAN sub-interfaces.";
      }
      description
        "Additions for L2 DHCPv4 Relay Agent on the VLAN
       sub-interface.";
      container l2-dhcpv4-relay {
        presence
          "Presence of this container indicates L2 DHCPv4 Relay Agent
         functionality is supported on this interface.";
        description
          "L2 DHCPv4 Relay Agent configuration parameters.";
        leaf enable {
          type boolean;
          default "false";
          description
            "Manage the L2 DHCP Relay Agent option 82 functionality.";
        }

        leaf trusted-port {
          type boolean;
          default "false";
          description
            "On a trusted port the option 82 from the user is accepted
           in upstream messages, and it is not removed from downstream
           messages.";
        }

        leaf profile-ref {
          when "../enable = 'true'" {
            description
              "Applicable only when L2 DHCPv4 Relay Agent functionality
             is enabled.";
          }
          type leafref {
            path "/bbf-l2-d4r:l2-dhcpv4-relay-profiles/bbf-l2-d4r:l2-dhcpv4-relay-profile/bbf-l2-d4r:name";
          }
          mandatory true;
          description
            "Reference to the DHCPv4 configuration profile.";
        }
      }  // container l2-dhcpv4-relay
    }

    container l2-dhcpv4-relay-profiles {
      description
        "L2 DHCPv4 Relay Agent configuration profiles.";
      list l2-dhcpv4-relay-profile {
        key "name";
        description
          "List containing the parameters for L2 DHCPv4 Relay Agent
         configuration.";
        leaf name {
          type bbf-yang:string-ascii64;
          description "Name of the profile.";
        }

        leaf max-packet-size {
          type uint16;
          units "bytes";
          default "1500";
          description
            "The maximum size of the DHCP message to be created after
           appending the Agent Information option. Messages which,
           after appending the Relay Agent Information option, would
           exceed this configured maximum size shall be forwarded
           WITHOUT adding the Agent Information option.

           The 'max-packet-size' expresses the maximum size of the IP
           packet, i.e. the payload of the Ethernet frame, i.e. it
           excludes the Ethernet header and possible VLAN tags, it
           includes the IP header, the UDP header, and the DHCP
           message itself.";
          reference
            "RFC 3046 - Section 2.1";

        }

        container option82-format {
          description
            "Contains information that needs to be filled
           in option 82";
          leaf-list suboptions {
            type enumeration {
              enum "circuit-id" {
                value 0;
                description
                  "Add the sub-option circuit ID in option 82, i.e. add
                 the sub-option with code 0x01.

                 The value inserted is the value of the leaf
                 circuit-id defined in the instance in the list
                 subscriber-profiles/subscriber-profile that is
                 associated with the interface, if any. If this leaf
                 is unknown, then a sub-option circuit ID will be
                 generated according to the syntax defined in the leaf
                 default-circuit-id-syntax.";
                reference
                  "RFC 3046 - Section 3.1";

              }
              enum "remote-id" {
                value 1;
                description
                  "Add the sub-option remote ID in option 82, i.e. add
                 the sub-option with code 0x02.

                 The value inserted is the value of the leaf remote-id
                 defined in the instance in the list
                 subscriber-profiles/subscriber-profile that is
                 associated with the interface, if any. If this leaf
                 is unknown, then a sub-option remote ID will be
                 generated according to the syntax defined in the leaf
                 default-remote-id-syntax.";
                reference
                  "RFC 3046 - Section 3.2";

              }
              enum
                "access-loop-characteristics" {
                value 2;
                description
                  "Signal the access loop characteristics in option 82.
                 Access-loop-characteristics are added using the
                 vendor-specific sub-option with code 0x09.

                 The content of the sub-option is controlled via the
                 leaf access-loop-suboptions.";
                reference
                  "RFC 4243 - Sections 3 & 4";

              }
            }
            min-elements 1;
            description
              "Identifies the sub-options that should be part of
             option 82.";
          }

          leaf default-circuit-id-syntax {
            type bbf-yang:string-ascii63-or-empty;
            default "";
            description
              "To be used to generate a sub-option circuit ID when no
             circuit-id is provided for the VLAN sub-interface via a
             referenced subscriber-profiles/subscriber-profile.

             The syntax is a string of ASCII characters that
             determines the actual value inserted in the sub-option.
             Parts of the syntax that are recognized as predefined
             keywords will be replaced by an actual value.";
            reference
              "TR-178 - R117";

          }

          leaf default-remote-id-syntax {
            type bbf-yang:string-ascii63-or-empty;
            default "";
            description
              "To be used to generate a sub-option remote ID when no
             remote-id is provided for the VLAN sub-interface via a
             referenced subscriber-profiles/subscriber-profile.

             The syntax is a string of ASCII characters that
             determines the actual value inserted in the sub-option.
             Parts of the syntax that are recognized as predefined
             keywords will be replaced by an actual value.";
            reference
              "TR-178 - R120";

          }

          leaf access-loop-suboptions {
            type bbf-subtype:broadband-line-characteristics;
            default "";
            description
              "Broadband line characteristics that are to be added in
             option 82.";
            reference
              "TR-178 - R121";

          }

          leaf start-numbering-from-zero {
            type boolean;
            default "false";
            description
              "In case the default-circuit-id-syntax or
             default-remote-id-syntax indicates a Slot or a Port
             identification shall be added to the sub-option value,
             then this leaf determines if the slot/port numbering
             MUST start from 0 or 1.";
            reference
              "TR-178 - R118";

          }

          leaf use-leading-zeroes {
            type boolean;
            default "false";
            description
              "In case the default-circuit-id-syntax or
             default-remote-id-syntax indicates a Slot or a Port
             identification shall be added to the sub-option value,
             then this leaf determines if the slot/port numbering
             MUST use leading 0's or not, i.e., generate a fixed-
             length string or a string with only meaningful digits.

             Note that the number of digits used to form the fixed-
             length string is device specific. A device may use the
             number of digits as specified in TR-101 Table 2/
             TR-156 Table 1 or a device may determine the number of
             digits by the maximum value for the Slot or a Port
             identification applicable to the device, i.e., if the
             maximum value is less than or equal to 9, one digit may
             be used; if the maximum value is less than or equal to
             99, two digits may be used, etc.";
            reference
              "TR-178 - R119;
              TR-101i2 - Table 2 Circuit ID Syntax;
              TR-156 - Table 1 Port Identification String Elements.";

          }
        }  // container option82-format
      }  // list l2-dhcpv4-relay-profile
    }  // container l2-dhcpv4-relay-profiles

    augment /if:interfaces-state/if:interface/if:statistics {
      when
        "derived-from-or-self(../if:type,
                               'bbfift:vlan-sub-interface')" {
        description
          "Applies only to VLAN sub-interfaces and only when the L2
         DHCPv4 Relay Agent functionality is enabled.";
      }
      description
        "L2 DHCPv4 Relay Agent statistics.";
      container dhcpv4 {
        presence
          "Statistics are provided when the L2 DHCPv4 Relay Agent
                functionality is enabled";
        description
          "Container presents the message statistics related to the L2
         DHCPv4 Relay Agent.";
        leaf in-bad-packets-from-client {
          type yang:counter32;
          description
            "Bad DHCPv4 messages received on the interface. The messages
           are received from a DHCPv4 Client connected to it (directly
           or indirectly through a network).

           Discontinuities in the counter can occur at
           re-initialization of the management system, and/or when the
           L2 DHCPv4 Relay functionality is disabled/enabled.";
        }

        leaf in-bad-packets-from-server {
          type yang:counter32;
          description
            "Bad DHCPv4 messages received on the interface. The messages
           are received from a DHCPv4 Server connected to it (directly
           or indirectly through a network).

           Discontinuities in the counter can occur at
           re-initialization of the management system, and/or when the
           L2 DHCPv4 Relay functionality is disabled/enabled.";
        }

        leaf in-packets-from-client {
          type yang:counter32;
          description
            "Valid DHCPv4 messages received on the interface. The
           messages are received from a DHCPv4 Client connected to it
           (directly or indirectly through a network).

           Discontinuities in the counter can occur at
           re-initialization of the management system, and/or when the
           L2 DHCPv4 Relay functionality is disabled/enabled.";
        }

        leaf in-packets-from-server {
          type yang:counter32;
          description
            "Valid DHCPv4 messages received on the interface. The
           messages are received from a DHCPv4 Server connected to it
           (directly or indirectly through a network).

           Discontinuities in the counter can occur at
           re-initialization of the management system, and/or when the
           L2 DHCPv4 Relay functionality is disabled/enabled.";
        }

        leaf out-packets-to-server {
          type yang:counter32;
          description
            "Valid DHCPv4 messages sent to the interface. The messages
           are sent to a DHCPv4 Server connected to it (directly or
           indirectly through a network).

           Discontinuities in the counter can occur at
           re-initialization of the management system, and/or when the
           L2 DHCPv4 Relay functionality is disabled/enabled.";
        }

        leaf out-packets-to-client {
          type yang:counter32;
          description
            "Valid DHCPv4 messages sent to the interface. The messages
           are sent to a DHCPv4 Client connected to it (directly or
           indirectly through a network).

           Discontinuities in the counter can occur at
           re-initialization of the management system, and/or when the
           L2 DHCPv4 Relay functionality is disabled/enabled.";
        }

        leaf option-82-inserted-packets-to-server {
          type yang:counter32;
          description
            "DHCPv4 messages from a Client to a Server that pass this
           interface and into which the L2 DHCPv4 Relay inserted
           option 82.

           Discontinuities in the counter can occur at
           re-initialization of the management system, and/or when the
           L2 DHCPv4 Relay functionality is disabled/enabled.";
        }

        leaf option-82-removed-packets-to-client {
          type yang:counter32;
          description
            "DHCPv4 messages from a Server to a Client that pass this
           interface and from which the L2 DHCPv4 Relay removed
           option 82.

           Discontinuities in the counter can occur at
           re-initialization of the management system, and/or when the
           L2 DHCPv4 Relay functionality is disabled/enabled.";
        }

        leaf option-82-not-inserted-to-server {
          type yang:counter32;
          description
            "DHCPv4 messages from a Client to a Server that pass this
           interface and for which the L2 DHCPv4 Relay did not insert
           option 82 because after insertion the length would exceed
           the maximum allowed packet size.

           Discontinuities in the counter can occur at
           re-initialization of the management system, and/or when the
           L2 DHCPv4 Relay functionality is disabled/enabled.";
        }
      }  // container dhcpv4
    }
  }  // module bbf-l2-dhcpv4-relay