module ietf-access-control-list {
  yang-version 1.1;
  namespace "urn:ietf:params:xml:ns:yang:ietf-access-control-list";
  prefix acl;

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

  import ietf-packet-fields {
    prefix pf;
    reference
    "RFC XXXX - Network ACL YANG Model.";
  }

  import ietf-interfaces {
    prefix if;
    reference
      "RFC 8343 - A YANG Data Model for Interface Management.";
  }

  organization
    "IETF NETMOD (Network Modeling Language)
     Working Group";

  contact
    "WG Web: http://tools.ietf.org/wg/netmod/
     WG List: netmod@ietf.org

     Editor: Mahesh Jethanandani
             mjethanandani@gmail.com
     Editor: Lisa Huang
             lyihuang16@gmail.com
     Editor: Sonal Agarwal
             sagarwal12@gmail.com
     Editor: Dana Blair
             dblair@cisco.com";

  description
    "This YANG module defines a component that describe the
     configuration of Access Control Lists (ACLs).

     Copyright (c) 2018 IETF Trust and the persons identified as
     the document authors.  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
     (http://trustee.ietf.org/license-info).

     This version of this YANG module is part of RFC XXXX; see
     the RFC itself for full legal notices.";

  revision 2018-10-01 {
    description
      "Initial version.";
    reference
      "RFC XXX: Network Access Control List (ACL) YANG Data Model.";
  }

  /*
   * Identities
   */
  /*
   * Forwarding actions for a packet
   */
  identity forwarding-action {
    description
      "Base identity for actions in the forwarding category";
  }

  identity accept {
    base forwarding-action;
    description
      "Accept the packet";
  }

  identity drop {
    base forwarding-action;
    description
      "Drop packet without sending any ICMP error message";
  }

  identity reject {
    base forwarding-action;
    description
      "Drop the packet and send an ICMP error message to the source";
  }

  /*
   * Logging actions for a packet
   */
  identity log-action {
    description
      "Base identity for defining the destination for logging actions";
  }

  identity log-syslog {
    base log-action;
    description
      "System log (syslog) the information for the packet";
  }

  identity log-none {
    base log-action;
    description
      "No logging for the packet";
  }

  /*
   * ACL type identities
   */
  identity acl-base {
    description
      "Base Access Control List type for all Access Control List type
       identifiers.";
  }

  identity ipv4-acl-type {
    base acl:acl-base;
    if-feature "ipv4";
    description
      "An ACL that matches on fields from the IPv4 header
       (e.g. IPv4 destination address) and layer 4 headers (e.g. TCP
       destination port).  An acl of type ipv4 does not contain
       matches on fields in the ethernet header or the IPv6 header.";
  }

  identity ipv6-acl-type {
    base acl:acl-base;
    if-feature "ipv6";
    description
      "An ACL that matches on fields from the IPv6 header
       (e.g. IPv6 destination address) and layer 4 headers (e.g. TCP
       destination port). An acl of type ipv6 does not contain
       matches on fields in the ethernet header or the IPv4 header.";
  }

  identity eth-acl-type {
    base acl:acl-base;
    if-feature "eth";
    description
      "An ACL that matches on fields in the ethernet header,
       like 10/100/1000baseT or WiFi Access Control List. An acl of
       type ethernet does not contain matches on fields in the IPv4
       header, IPv6 header or layer 4 headers.";
  }

  identity mixed-eth-ipv4-acl-type {
    base "acl:eth-acl-type";
    base "acl:ipv4-acl-type";
    if-feature "mixed-eth-ipv4";
    description
      "An ACL that contains a mix of entries that
       match on fields in ethernet headers,
       entries that match on IPv4 headers.
       Matching on layer 4 header fields may also exist in the
       list.";
  }
  identity mixed-eth-ipv6-acl-type {
    base "acl:eth-acl-type";
    base "acl:ipv6-acl-type";
    if-feature "mixed-eth-ipv6";
    description
      "ACL that contains a mix of entries that
       match on fields in ethernet headers, entries
       that match on fields in IPv6 headers. Matching on
       layer 4 header fields may also exist in the list.";
  }

  identity mixed-eth-ipv4-ipv6-acl-type {
    base "acl:eth-acl-type";
    base "acl:ipv4-acl-type";
    base "acl:ipv6-acl-type";
    if-feature "mixed-eth-ipv4-ipv6";
    description
      "ACL that contains a mix of entries that
       match on fields in ethernet headers, entries
       that match on fields in IPv4 headers, and entries
       that match on fields in IPv6 headers. Matching on
       layer 4 header fields may also exist in the list.";
  }

  /*
   * Features
   */

  /*
   * Features supported by device
   */
  feature match-on-eth {
    description
      "The device can support matching on ethernet headers.";
  }

  feature match-on-ipv4 {
    description
      "The device can support matching on IPv4 headers.";
  }

  feature match-on-ipv6 {
    description
      "The device can support matching on IPv6 headers.";
  }

  feature match-on-tcp {
    description
      "The device can support matching on TCP headers.";
  }

  feature match-on-udp {
    description
      "The device can support matching on UDP headers.";
  }

  feature match-on-icmp {
    description
      "The device can support matching on ICMP (v4 and v6) headers.";
  }

  /*
   * Header classifications combinations supported by
   * device
   */
  feature eth {
    if-feature "match-on-eth";
    description
      "Plain Ethernet ACL supported";
  }

  feature ipv4 {
    if-feature "match-on-ipv4";
    description
      "Plain IPv4 ACL supported";
  }

  feature ipv6 {
    if-feature "match-on-ipv6";
    description
      "Plain IPv6 ACL supported";
  }

  feature mixed-eth-ipv4 {
    if-feature "match-on-eth and match-on-ipv4";
    description
      "Ethernet and IPv4 ACL combinations supported";
  }

  feature mixed-eth-ipv6 {
    if-feature "match-on-eth and match-on-ipv6";
    description
      "Ethernet and IPv6 ACL combinations supported";
  }

  feature mixed-eth-ipv4-ipv6 {
    if-feature "match-on-eth and match-on-ipv4
                and match-on-ipv6";
    description
      "Ethernet, IPv4 and IPv6 ACL combinations supported.";
  }

  /*
   * Stats Features
   */
  feature interface-stats {
    description
      "ACL counters are available and reported only per interface";
  }

  feature acl-aggregate-stats {
    description
      "ACL counters are aggregated over all interfaces, and reported
       only per ACL entry";
  }

  /*
   * Attachment point features
   */
  feature interface-attachment {
    description
      "ACLs are set on interfaces.";
  }

  /*
   * Typedefs
   */
  typedef acl-type {
    type identityref {
      base acl-base;
    }
    description
      "This type is used to refer to an Access Control List
       (ACL) type";
  }

  /*
   * Groupings
   */
  grouping acl-counters {
    description
      "Common grouping for ACL counters";

    leaf matched-packets {
      type yang:counter64;
      config false;
      description
        "Count of the number of packets matching the current ACL
         entry.

         An implementation should provide this counter on a
         per-interface per-ACL-entry basis if possible.

         If an implementation only supports ACL counters on a per
         entry basis (i.e., not broken out per interface), then the
         value should be equal to the aggregate count across all
         interfaces.

         An implementation that provides counters on a per entry per
         interface basis is not required to also provide an aggregate
         count, e.g., per entry -- the user is expected to be able
         implement the required aggregation if such a count is
         needed.";
    }

    leaf matched-octets {
      type yang:counter64;
      config false;
      description
        "Count of the number of octets (bytes) matching the current
         ACL entry.

         An implementation should provide this counter on a
         per-interface per-ACL-entry if possible.

         If an implementation only supports ACL counters per entry
         (i.e., not broken out per interface), then the value
         should be equal to the aggregate count across all interfaces.

         An implementation that provides counters per entry per
         interface is not required to also provide an aggregate count,
         e.g., per entry -- the user is expected to be able implement
         the required aggregation if such a count is needed.";
    }
  }

  /*
   * Configuration data nodes
   */
  container acls {
    description
      "This is a top level container for Access Control Lists.
       It can have one or more acl nodes.";
    list acl {
      key "name";
      description
        "An Access Control List (ACL) is an ordered list of
         Access Control Entries (ACE). Each ACE has a
         list of match criteria and a list of actions.
         Since there are several kinds of Access Control Lists
         implemented with different attributes for
         different vendors, this model accommodates customizing
         Access Control Lists for each kind and, for each vendor.";
      leaf name {
        type string {
          length "1..64";
        }
        description
          "The name of access list. A device MAY restrict the length
           and value of this name, possibly space and special
           characters are not allowed.";
      }
      leaf type {
        type acl-type;
        description
          "Type of access control list. Indicates the primary intended
           type of match criteria (e.g. ethernet, IPv4, IPv6, mixed,
           etc) used in the list instance.";
      }
      container aces {
        description
          "The aces container contains one or more ace nodes.";
        list ace {
          key "name";
          ordered-by user;
          description
            "List of Access Control Entries (ACEs)";
          leaf name {
            type string {
              length "1..64";
            }
            description
              "A unique name identifying this Access Control
               Entry (ACE).";
          }

          container matches {
            description
              "The rules in this set determine what fields will be
               matched upon before any action is taken on them.
               The rules are selected based on the feature set
               defined by the server and the acl-type defined.
               If no matches are defined in a particular container,
               then any packet will match that container. If no
               matches are specified at all in an ACE, then any
               packet will match the ACE.";

            choice l2 {
              container eth {
                when "derived-from-or-self(/acls/acl/type, " +
                     "'acl:eth-acl-type')";
                if-feature match-on-eth;
                uses pf:acl-eth-header-fields;
                description
                  "Rule set that matches ethernet headers.";
              }
              description
                "Match layer 2 headers, for example ethernet
                 header fields.";
            }

            choice l3 {
              container ipv4 {
                when "derived-from-or-self(/acls/acl/type, " +
                     "'acl:ipv4-acl-type')";
                if-feature match-on-ipv4;
                uses pf:acl-ip-header-fields;
                uses pf:acl-ipv4-header-fields;
                description
                  "Rule set that matches IPv4 headers.";
              }

              container ipv6 {
                when "derived-from-or-self(/acls/acl/type, " +
                     "'acl:ipv6-acl-type')";
                if-feature match-on-ipv6;
                uses pf:acl-ip-header-fields;
                uses pf:acl-ipv6-header-fields;
                description
                  "Rule set that matches IPv6 headers.";
              }
              description
                "Choice of either ipv4 or ipv6 headers";
            }

            choice l4 {
              container tcp {
                if-feature match-on-tcp;
                uses pf:acl-tcp-header-fields;
                container source-port {
                  choice source-port {
                    case range-or-operator {
                      uses pf:port-range-or-operator;
                      description
                        "Source port definition from range or
                         operator.";
                    }
                    description
                      "Choice of source port definition using
                       range/operator or a choice to support future
                       'case' statements, such as one enabling a
                       group of source ports to be referenced.";
                  }
                  description
                    "Source port definition.";
                }
                container destination-port {
                  choice destination-port {
                    case range-or-operator {
                      uses pf:port-range-or-operator;
                      description
                        "Destination port definition from range or
                         operator.";
                    }
                    description
                      "Choice of destination port definition using
                       range/operator or a choice to support future
                       'case' statements, such as one enabling a
                       group of destination ports to be referenced.";
                  }
                  description
                    "Destination port definition.";
                }
                description
                  "Rule set that matches TCP headers.";
              }

              container udp {
                if-feature match-on-udp;
                uses pf:acl-udp-header-fields;
                container source-port {
                  choice source-port {
                    case range-or-operator {
                      uses pf:port-range-or-operator;
                      description
                        "Source port definition from range or
                         operator.";
                    }
                    description
                      "Choice of source port definition using
                       range/operator or a choice to support future
                       'case' statements, such as one enabling a
                       group of source ports to be referenced.";
                  }
                  description
                    "Source port definition.";
                }
                container destination-port {
                  choice destination-port {
                    case range-or-operator {
                      uses pf:port-range-or-operator;
                      description
                        "Destination port definition from range or
                         operator.";
                    }
                    description
                      "Choice of destination port definition using
                       range/operator or a choice to support future
                       'case' statements, such as one enabling a
                       group of destination ports to be referenced.";
                  }
                  description
                    "Destination port definition.";
                }
                description
                  "Rule set that matches UDP headers.";
              }

              container icmp {
                if-feature match-on-icmp;
                uses pf:acl-icmp-header-fields;
                description
                  "Rule set that matches ICMP headers.";
              }
              description
                "Choice of TCP, UDP or ICMP headers.";
            }

            leaf egress-interface {
              type if:interface-ref;
              description
                "Egress interface. This should not be used if this ACL
                 is attached as an egress ACL (or the value should
                 equal the interface to which the ACL is attached).";
            }

            leaf ingress-interface {
              type if:interface-ref;
              description
                "Ingress interface. This should not be used if this ACL
                 is attached as an ingress ACL (or the value should
                 equal the interface to which the ACL is attached)";
            }
          }

          container actions {
            description
              "Definitions of action for this ace entry";
            leaf forwarding {
              type identityref {
                base forwarding-action;
              }
              mandatory true;
              description
                "Specifies the forwarding action per ace entry";
            }

            leaf logging {
              type identityref {
                base log-action;
              }
              default log-none;
              description
                "Specifies the log action and destination for
                 matched packets. Default value is not to log the
                 packet.";
            }
          }
          container statistics {
            if-feature "acl-aggregate-stats";
            config false;
            description
              "Statistics gathered across all attachment points for the
               given ACL.";
            uses acl-counters;
          }
        }
      }
    }
    container attachment-points {
      description
        "Enclosing container for the list of
         attachment-points on which ACLs are set";

      /*
       * Groupings
       */
      grouping interface-acl {
        description
          "Grouping for per-interface ingress ACL data";

        container acl-sets {
          description
            "Enclosing container the list of ingress ACLs on the
             interface";

          list acl-set {
            key "name";
            ordered-by user;
            description
              "List of ingress ACLs on the interface";

            leaf name {
              type leafref {
                path "/acls/acl/name";
              }
              description
                "Reference to the ACL name applied on ingress";
            }

            list ace-statistics {
              if-feature "interface-stats";
              key "name";
              config false;
              description
                "List of Access Control Entries (ACEs)";
              leaf name {
                type leafref {
                  path "/acls/acl/aces/ace/name";
                }
                description
                  "The ace name";
              }
              uses acl-counters;
            }
          }
        }
      }

      list interface {
        if-feature interface-attachment;
        key "interface-id";
        description
          "List of interfaces on which ACLs are set";

        leaf interface-id {
          type if:interface-ref;
          description
            "Reference to the interface id list key";
        }

        container ingress {
          uses interface-acl;
          description
            "The ACLs applied to ingress interface";
        }
        container egress {
          uses interface-acl;
          description
            "The ACLs applied to egress interface";
        }
      }
    }
  }
}