module ietf-nat { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-nat"; //namespace to be assigned by IANA prefix "nat"; import ietf-inet-types { prefix inet; } import ietf-yang-types { prefix yang; } import ietf-interfaces { prefix if; } organization "IETF OPSAWG (Operations and Management Area Working Group)"; contact "WG Web: WG List: Editor: Mohamed Boucadair Editor: Senthil Sivakumar Editor: Christian Jacquenet Editor: Suresh Vinapamula Editor: Qin Wu "; description "This module is a YANG module for NAT implementations. NAT44, Network Address and Protocol Translation from IPv6 Clients to IPv4 Servers (NAT64), Customer-side transLATor (CLAT), Stateless IP/ICMP Translation (SIIT), Explicit Address Mappings for Stateless IP/ICMP Translation (SIIT EAM), and IPv6 Network Prefix Translation (NPTv6) are covered. Copyright (c) 2017 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 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 2017-11-16 { description "Initial revision."; reference "RFC XXXX: A YANG Data Model for Network Address Translation (NAT) and Network Prefix Translation (NPT)"; } /* * Definitions */ typedef percent { type uint8 { range "0 .. 100"; } description "Percentage"; } /* * Features */ feature basic-nat44{ description "Basic NAT44 translation is limited to IP addresses alone."; reference "RFC 3022: Traditional IP Network Address Translator (Traditional NAT)"; } feature napt44 { description "Network Address/Port Translator (NAPT): translation is extended to include IP addresses and transport identifiers (such as a TCP/UDP port or ICMP query ID). If the internal IP address is not sufficient to uniquely disambiguate NAPT44 mappings, an additional attribute is required. For example, that additional attribute may be an IPv6 address (a.k.a., DS-Lite (RFC 6333)) or a Layer 2 identifier (a.k.a., Per-Interface NAT (RFC 6619))"; reference "RFC 3022: Traditional IP Network Address Translator (Traditional NAT)"; } feature dst-nat { description "Destination NAT is a translation that acts on the destination IP address and/or destination port number. This flavor is usually deployed in load balancers or at devices in front of public servers."; } feature nat64 { description "NAT64 translation allows IPv6-only clients to contact IPv4 servers using unicast UDP, TCP, or ICMP. One or more public IPv4 addresses assigned to a NAT64 translator are shared among several IPv6-only clients."; reference "RFC 6146: Stateful NAT64: Network Address and Protocol Translation from IPv6 Clients to IPv4 Servers"; } feature siit { description "The Stateless IP/ICMP Translation Algorithm (SIIT), which translates between IPv4 and IPv6 packet headers (including ICMP headers). In the stateless mode, an IP/ICMP translator converts IPv4 addresses to IPv6 and vice versa solely based on the configuration of the stateless IP/ICMP translator and information contained within the packet being translated. The translator must support the stateless address mapping algorithm defined in RFC6052, which is the default behavior."; reference "RFC 7915: IP/ICMP Translation Algorithm"; } feature clat { description "CLAT is customer-side translator that algorithmically translates 1:1 private IPv4 addresses to global IPv6 addresses, and vice versa. When a dedicated /64 prefix is not available for translation from DHCPv6-PD, the CLAT may perform NAT44 for all IPv4 LAN packets so that all the LAN-originated IPv4 packets appear from a single IPv4 address and are then statelessly translated to one interface IPv6 address that is claimed by the CLAT via the Neighbor Discovery Protocol (NDP) and defended with Duplicate Address Detection."; reference "RFC 6877: 464XLAT: Combination of Stateful and Stateless Translation"; } feature eam { description "Explicit Address Mapping (EAM) is a bidirectional coupling between an IPv4 Prefix and an IPv6 Prefix."; reference "RFC 7757: Explicit Address Mappings for Stateless IP/ICMP Translation"; } feature nptv6 { description "NPTv6 is a stateless transport-agnostic IPv6-to-IPv6 prefix translation."; reference "RFC 6296: IPv6-to-IPv6 Network Prefix Translation"; } /* * Identities */ identity nat-type { description "Base identity for nat type."; } identity basic-nat44 { base nat:nat-type; description "Identity for Basic NAT support."; reference "RFC 3022: Traditional IP Network Address Translator (Traditional NAT)"; } identity napt44 { base nat:nat-type; description "Identity for NAPT support."; reference "RFC 3022: Traditional IP Network Address Translator (Traditional NAT)"; } identity dst-nat { base nat:nat-type; description "Identity for Destination NAT support."; } identity nat64 { base nat:nat-type; description "Identity for NAT64 support."; reference "RFC 6146: Stateful NAT64: Network Address and Protocol Translation from IPv6 Clients to IPv4 Servers"; } identity siit { base nat:nat-type; description "Identity for SIIT support."; reference "RFC 7915: IP/ICMP Translation Algorithm"; } identity clat { base nat:nat-type; description "Identity for CLAT support."; reference "RFC 6877: 464XLAT: Combination of Stateful and Stateless Translation"; } identity eam { base nat:nat-type; description "Identity for EAM support."; reference "RFC 7757: Explicit Address Mappings for Stateless IP/ICMP Translation"; } identity nptv6 { base nat:nat-type; description "Identity for NPTv6 support."; reference "RFC 6296: IPv6-to-IPv6 Network Prefix Translation"; } /* * Grouping */ grouping port-number { description "Individual port or a range of ports. When only start-port-number is present, it represents a single port."; leaf start-port-number { type inet:port-number; description "Begining of the port range."; reference "Section 3.2.9 of RFC 8045."; } leaf end-port-number { type inet:port-number; must ". >= ../start-port-number" { error-message "The end-port-number must be greater than or equal to start-port-number."; } description "End of the port range."; reference "Section 3.2.10 of RFC 8045."; } } grouping port-set { description "Indicates a set of ports. It may be a simple port range, or use the Port Set ID (PSID) algorithm to represent a range of transport layer ports which will be used by a NAPT."; choice port-type { default port-range; description "Port type: port-range or port-set-algo."; case port-range { uses port-number; } case port-set-algo { leaf psid-offset { type uint8 { range 0..15; } description "The number of offset bits (a.k.a., 'a' bits). Specifies the numeric value for the excluded port range/offset bits. Allowed values are between 0 and 15 "; reference "Section 5.1 of RFC 7597"; } leaf psid-len { type uint8 { range 0..15; } mandatory true; description "The length of PSID, representing the sharing ratio for an IPv4 address. (also known as 'k'). The address-sharing ratio would be 2^k."; reference "Section 5.1 of RFC 7597"; } leaf psid { type uint16; mandatory true; description "Port Set Identifier (PSID) value, which identifies a set of ports algorithmically."; reference "Section 5.1 of RFC 7597"; } } reference "Section 7597: Mapping of Address and Port with Encapsulation (MAP-E)"; } } grouping mapping-entry { description "NAT mapping entry. If an attribute is not stored in the mapping/session table, this means the corresponding fields of a packet that matches this entry is not rewritten by the NAT or this information is not required for NAT filtering purposes."; leaf index { type uint32; description "A unique identifier of a mapping entry. This identifier can be automatically assigned by the NAT instance or be explicitly configured."; } leaf type { type enumeration { enum "static" { description "The mapping entry is explicitly configured (e.g., via command-line interface)."; } enum "dynamic-implicit" { description "This mapping is created implicitly as a side effect of processing a packet that requires a new mapping."; } enum "dynamic-explicit" { description "This mapping is created as a result of an explicit request, e.g., a PCP message."; } } description "Indicates the type of a mapping entry. E.g., a mapping can be: static, implicit dynamic or explicit dynamic."; } leaf transport-protocol { type uint8; description "Upper-layer protocol associated with this mapping. Values are taken from the IANA protocol registry. For example, this field contains 6 (TCP) for a TCP mapping or 17 (UDP) for a UDP mapping. If this leaf is not instantiated, then the mapping applies to any protocol."; } leaf internal-src-address { type inet:ip-prefix; description "Corresponds to the source IPv4/IPv6 address/prefix of the packet received on an internal interface."; } container internal-src-port { description "Corresponds to the source port of the packet received on an internal interface. It is used also to indicate the internal source ICMP identifier. As a reminder, all the ICMP Query messages contain an 'Identifier' field, which is referred to in this document as the 'ICMP Identifier'."; uses port-number; } leaf external-src-address { type inet:ip-prefix; description "Source IP address/prefix of the packet sent on an external interface of the NAT."; } container external-src-port { description "Source port of the packet sent on an external interface of the NAT. It is used also to indicate the external source ICMP identifier."; uses port-number; } leaf internal-dst-address { type inet:ip-prefix; description "Corresponds to the destination IP address/prefix of the packet received on an internal interface of the NAT. For example, some NAT implementations support the translation of both source and destination addresses and ports, sometimes referred to as 'Twice NAT'."; } container internal-dst-port { description "Corresponds to the destination port of the IP packet received on the internal interface. It is used also to include the internal destination ICMP identifier."; uses port-number; } leaf external-dst-address { type inet:ip-prefix; description "Corresponds to the destination IP address/prefix of the packet sent on an external interface of the NAT."; } container external-dst-port { description "Corresponds to the destination port number of the packet sent on the external interface of the NAT. It is used also to include the external destination ICMP identifier."; uses port-number; } leaf lifetime { type uint32; units "seconds"; description "When specified, it is used to track the connection that is fully-formed (e.g., once the three-way handshake TCP is completed) or the duration for maintaining an explicit mapping alive. The mapping entry will be removed by the NAT instance once this lifetime is expired. When reported in a get operation, the lifetime indicates the remaining validity lifetime. Static mappings may not be associated with a lifetime. If no lifetime is associated with a static mapping, an explicit action is required to remove that mapping."; } } /* * NAT Module */ container nat { description "NAT module"; container instances { description "NAT instances"; list instance { key "id"; description "A NAT instance. This identifier can be automatically assigned or explicitly configured."; leaf id { type uint32; must ". >= 1"; description "NAT instance identifier. The identifier must be greater than zero as per RFC 7659."; reference "RFC 7659: Definitions of Managed Objects for Network Address Translators (NATs)"; } leaf name { type string; description "A name associated with the NAT instance."; reference "RFC 7659: Definitions of Managed Objects for Network Address Translators (NATs)"; } leaf enable { type boolean; description "Status of the NAT instance."; } container capabilities { config false; description "NAT capabilities"; leaf-list nat-flavor { type identityref { base nat-type; } description "Supported translation type(s)."; } leaf-list per-interface-binding { type enumeration { enum "unsupported" { description "No capability to associate a NAT binding with an extra identifier."; } enum "layer-2" { description "The NAT instance is able to associate a mapping with a layer-2 identifier."; } enum "dslite" { description "The NAT instance is able to associate a mapping with an IPv6 address (a.k.a., DS-Lite)."; } } description "Indicates the capability of a NAT to associate a particular NAT session not only with the five tuples used for the transport connection on both sides of the NAT but also with the internal interface on which the user device is connected to the NAT."; reference "Section 4 of RFC 6619"; } list transport-protocols { key protocol-id; description "List of supported protocols."; leaf protocol-id { type uint8; mandatory true; description "Upper-layer protocol associated with this mapping. Values are taken from the IANA protocol registry: https://www.iana.org/assignments/protocol-numbers/ protocol-numbers.xhtml For example, this field contains 6 (TCP) for a TCP mapping or 17 (UDP) for a UDP mapping."; } leaf protocol-name { type string; description "The name of the Upper-layer protocol associated with this mapping. Values are taken from the IANA protocol registry: https://www.iana.org/assignments/protocol-numbers/ protocol-numbers.xhtml For example, TCP, UDP, DCCP, and SCTP."; } } leaf restricted-port-support { type boolean; description "Indicates source port NAT restriction support."; reference "RFC 7596: Lightweight 4over6: An Extension to the Dual-Stack Lite Architecture."; } leaf static-mapping-support { type boolean; description "Indicates whether static mappings are supported."; } leaf port-randomization-support { type boolean; description "Indicates whether port randomization is supported."; reference "Section 4.2.1 of RFC 4787."; } leaf port-range-allocation-support { type boolean; description "Indicates whether port range allocation is supported."; reference "Section 1.1 of RFC 7753."; } leaf port-preservation-suport { type boolean; description "Indicates whether port preservation is supported."; reference "Section 4.2.1 of RFC 4787."; } leaf port-parity-preservation-support { type boolean; description "Indicates whether port parity preservation is supported."; reference "Section 8 of RFC 7857."; } leaf address-roundrobin-support { type boolean; description "Indicates whether address allocation round robin is supported."; } leaf paired-address-pooling-support { type boolean; description "Indicates whether paired-address-pooling is supported"; reference "REQ-2 of RFC 4787."; } leaf endpoint-independent-mapping-support { type boolean; description "Indicates whether endpoint-independent- mapping in Section 4 of RFC 4787 is supported."; reference "Section 4 of RFC 4787."; } leaf address-dependent-mapping-support { type boolean; description "Indicates whether address-dependent-mapping is supported."; reference "Section 4 of RFC 4787."; } leaf address-and-port-dependent-mapping-support { type boolean; description "Indicates whether address-and-port-dependent-mapping is supported."; reference "Section 4 of RFC 4787."; } leaf endpoint-independent-filtering-support { type boolean; description "Indicates whether endpoint-independent-filtering is supported."; reference "Section 5 of RFC 4787."; } leaf address-dependent-filtering { type boolean; description "Indicates whether address-dependent-filtering is supported."; reference "Section 5 of RFC 4787."; } leaf address-and-port-dependent-filtering { type boolean; description "Indicates whether address-and-port-dependent is supported."; reference "Section 5 of RFC 4787."; } leaf fragment-behavior { type enumeration { enum "unsupported" { description "No capability to translate incoming fragments. All received fragments are dropped."; } enum "in-order" { description "The NAT instance is able to translate fragments only if they are received in order. That is, in particular the header is in the first packet. Fragments received out of order are dropped. "; } enum "out-of-order" { description "The NAT instance is able to translate a fragment even if it is received out of order. This behavior is the one recommended in RFC4787."; reference "REQ-14 of RFC 4787"; } } description "The fragment behavior is the NAT instance's capability to translate fragments received on the external interface of the NAT."; } } leaf type { type identityref { base nat-type; } description "Specify the translation type. Particularly useful when multiple translation flavors are supported. If one type is supported by a NAT, this parameter is by default set to that type."; } leaf per-interface-binding { type enumeration { enum "disabled" { description "Disable the capability to associate an extra identifier with NAT mappings."; } enum "layer-2" { description "The NAT instance is able to associate a mapping with a layer-2 identifier."; } enum "dslite" { description "The NAT instance is able to associate a mapping with an IPv6 address (a.k.a., DS-Lite)."; } } description "A NAT that associates a particular NAT session not only with the five tuples used for the transport connection on both sides of the NAT but also with the internal interface on which the user device is connected to the NAT. If supported, this mode of operation should be configurable, and it should be disabled by default in general-purpose NAT devices. If one single per-interface binding behavior is supported by a NAT, this parameter is by default set to that behavior."; reference "Section 4 of RFC 6619"; } list nat-pass-through { if-feature "basic-nat44 or napt44 or dst-nat"; key id; description "IP prefix NAT pass through."; leaf id { type uint32; description "An identifier of the IP prefix pass through."; } leaf prefix { type inet:ip-prefix; mandatory true; description "The IP addresses that match should not be translated. According to REQ#6 of RFC6888, it must be possible to administratively turn off translation for specific destination addresses and/or ports."; reference "REQ#6 of RFC6888."; } leaf port { type inet:port-number; description "According to REQ#6 of RFC6888, it must be possible to administratively turn off translation for specific destination addresses and/or ports. If no prefix is defined, the NAT pass through bound to a given port applies for any destination address."; reference "REQ#6 of RFC6888."; } } list policy { key id; description "NAT parameters for a given instance"; leaf id { type uint32; description "An identifier of the NAT policy. It must be unique within the NAT instance."; } container clat-parameters { if-feature clat; description "CLAT parameters."; list clat-ipv6-prefixes { key ipv6-prefix; description "464XLAT double translation treatment is stateless when a dedicated /64 is available for translation on the CLAT. Otherwise, the CLAT will have both stateful and stateless since it requires NAT44 from the LAN to a single IPv4 address and then stateless translation to a single IPv6 address."; reference "RFC 6877: 464XLAT: Combination of Stateful and Stateless Translation"; leaf ipv6-prefix { type inet:ipv6-prefix; description "An IPv6 prefix used for CLAT."; } } list ipv4-prefixes { key ipv4-prefix; description "Pool of IPv4 addresses used for CLAT. 192.0.0.0/29 is the IPv4 service continuity prefix."; reference "RFC 7335: IPv4 Service Continuity Prefix"; leaf ipv4-prefix { type inet:ipv4-prefix; description "464XLAT double translation treatment is stateless when a dedicated /64 is available for translation on the CLAT. Otherwise, the CLAT will have both stateful and stateless since it requires NAT44 from the LAN to a single IPv4 address and then stateless translation to a single IPv6 address. The CLAT performs NAT44 for all IPv4 LAN packets so that all the LAN-originated IPv4 packets appear from a single IPv4 address and are then statelessly translated to one interface IPv6 address that is claimed by the CLAT. An IPv4 address from this pool is also provided to an application that makes use of literals."; reference "RFC 6877: 464XLAT: Combination of Stateful and Stateless Translation"; } } } list nptv6-prefixes { if-feature nptv6; key internal-ipv6-prefix ; description "Provides one or a list of (internal IPv6 prefix, external IPv6 prefix) required for NPTv6. In its simplest form, NPTv6 interconnects two network links, one of which is an 'internal' network link attached to a leaf network within a single administrative domain and the other of which is an 'external' network with connectivity to the global Internet."; reference "RFC 6296: IPv6-to-IPv6 Network Prefix Translation"; leaf internal-ipv6-prefix { type inet:ipv6-prefix; mandatory true; description "An IPv6 prefix used by an internal interface of NPTv6."; reference "RFC 6296: IPv6-to-IPv6 Network Prefix Translation"; } leaf external-ipv6-prefix { type inet:ipv6-prefix; mandatory true; description "An IPv6 prefix used by the external interface of NPTv6."; reference "RFC 6296: IPv6-to-IPv6 Network Prefix Translation"; } } list eam { if-feature eam; key ipv4-prefix; description "The Explicit Address Mapping Table, a conceptual table in which each row represents an EAM. Each EAM describes a mapping between IPv4 and IPv6 prefixes/addresses."; reference "Section 3.1 of RFC 7757."; leaf ipv4-prefix { type inet:ipv4-prefix; mandatory true; description "The IPv4 prefix of an EAM."; reference "Section 3.2 of RFC 7757."; } leaf ipv6-prefix { type inet:ipv6-prefix; mandatory true; description "The IPv6 prefix of an EAM."; reference "Section 3.2 of RFC 7757."; } } list nat64-prefixes { if-feature "siit or nat64 or clat"; key nat64-prefix; description "Provides one or a list of NAT64 prefixes with or without a list of destination IPv4 prefixes. Destination-based Pref64::/n is discussed in Section 5.1 of [RFC7050]). For example: 192.0.2.0/24 is mapped to 2001:db8:122:300::/56. 198.51.100.0/24 is mapped to 2001:db8:122::/48."; reference "Section 5.1 of RFC7050."; leaf nat64-prefix { type inet:ipv6-prefix; mandatory true; description "A NAT64 prefix. Can be Network-Specific Prefix (NSP) or Well-Known Prefix (WKP). Organizations deploying stateless IPv4/IPv6 translation should assign a Network-Specific Prefix to their IPv4/IPv6 translation service. For stateless NAT64, IPv4-translatable IPv6 addresses must use the selected Network-Specific Prefix. Both IPv4-translatable IPv6 addresses and IPv4-converted IPv6 addresses should use the same prefix."; reference "Sections 3.3 and 3.4 of RFC 6052."; } list destination-ipv4-prefix { key ipv4-prefix; description "An IPv4 prefix/address."; leaf ipv4-prefix { type inet:ipv4-prefix; description "An IPv4 address/prefix."; } } leaf stateless-enable { type boolean; default false; description "Enable explicitly stateless NAT64."; } } list external-ip-address-pool { if-feature "basic-nat44 or napt44 or nat64"; key pool-id; description "Pool of external IP addresses used to service internal hosts. A pool is a set of IP prefixes."; leaf pool-id { type uint32; must ". >= 1"; description "An identifier that uniquely identifies the address pool within a NAT instance. The identifier must be greater than zero as per RFC 7659."; reference "RFC 7659: Definitions of Managed Objects for Network Address Translators (NATs)"; } leaf external-ip-pool { type inet:ipv4-prefix; mandatory true; description "An IPv4 prefix used for NAT purposes."; } } container port-set-restrict { if-feature "napt44 or nat64"; description "Configures contiguous and non-contiguous port ranges. The port set is used to restrict the external source port numbers used by the translator."; uses port-set; } leaf dst-nat-enable { if-feature "basic-nat44 or napt44"; type boolean; default false; description "Enable/Disable destination NAT. A NAT44 may be configured to enable Destination NAT, too."; } list dst-ip-address-pool { if-feature dst-nat; key pool-id; description "Pool of IP addresses used for destination NAT."; leaf pool-id { type uint32; description "An identifier of the address pool."; } leaf dst-in-ip-pool { type inet:ip-prefix; description "Is used to identify an internal IP prefix/address to be translated."; } leaf dst-out-ip-pool { type inet:ip-prefix; mandatory true; description "IP address/prefix used for destination NAT."; } } list transport-protocols { if-feature "napt44 or nat64 or dst-nat"; key protocol-id; description "Configure the transport protocols to be handled by the translator. TCP and UDP are supported by default."; leaf protocol-id { type uint8; mandatory true; description "Upper-layer protocol associated with this mapping. Values are taken from the IANA protocol registry: https://www.iana.org/assignments/protocol-numbers/ protocol-numbers.xhtml For example, this field contains 6 (TCP) for a TCP mapping or 17 (UDP) for a UDP mapping."; } leaf protocol-name { type string; description "The name of the Upper-layer protocol associated with this mapping. Values are taken from the IANA protocol registry: https://www.iana.org/assignments/protocol-numbers/ protocol-numbers.xhtml For example, TCP, UDP, DCCP, and SCTP."; } } leaf subscriber-mask-v6 { type uint8 { range "0 .. 128"; } description "The subscriber mask is an integer that indicates the length of significant bits to be applied on the source IPv6 address (internal side) to unambiguously identify a user device (e.g., CPE). Subscriber mask is a system-wide configuration parameter that is used to enforce generic per-subscriber policies (e.g., port-quota). The enforcement of these generic policies does not require the configuration of every subscriber's prefix. Example: suppose the 2001:db8:100:100::/56 prefix is assigned to a NAT64 serviced CPE. Suppose also that 2001:db8:100:100::1 is the IPv6 address used by the client that resides in that CPE. When the NAT64 receives a packet from this client, it applies the subscriber-mask-v6 (e.g., 56) on the source IPv6 address to compute the associated prefix for this client (2001:db8:100:100::/56). Then, the NAT64 enforces policies based on that prefix (2001:db8:100:100::/56), not on the exact source IPv6 address."; } list subscriber-match { if-feature "basic-nat44 or napt44 or dst-nat"; key match-id; description "IP prefix match. A subscriber is identified by a subnet."; leaf match-id { type uint32; description "An identifier of the subscriber match."; } leaf subnet { type inet:ip-prefix; mandatory true; description "The IP address subnets that match should be translated. E.g., all addresses that belong to the 192.0.2.0/24 prefix must be processed by the NAT."; } } leaf address-allocation-type { type enumeration { enum "arbitrary" { if-feature "basic-nat44 or napt44 or nat64"; description "Arbitrary pooling behavior means that the NAT instance may create the new port mapping using any address in the pool that has a free port for the protocol concerned."; } enum "roundrobin" { if-feature "basic-nat44 or napt44 or nat64"; description "Round robin allocation."; } enum "paired" { if-feature "napt44 or nat64"; description "Paired address pooling informs the NAT that all the flows from an internal IP address must be assigned the same external address. This is the recommended behavior for NAPT/NAT64."; reference "RFC 4787: Network Address Translation (NAT) Behavioral Requirements for Unicast UDP"; } } description "Specifies how external IP addresses are allocated."; } leaf port-allocation-type { if-feature "napt44 or nat64"; type enumeration { enum "random" { description "Port randomization is enabled. A NAT port allocation scheme should make it hard for attackers to guess port numbers"; reference "REQ-15 of RFC 6888"; } enum "port-preservation" { description "Indicates whether the NAT should preserve the internal port number."; } enum "port-parity-preservation" { description "Indicates whether the NAT should preserve the port parity of the internal port number."; } enum "port-range-allocation" { description "Indicates whether the NAT assigns a range of ports for an internal host. This scheme allows to minimize log volume."; reference "REQ-14 of RFC 6888"; } } description "Indicates the type of port allocation."; } leaf mapping-type { if-feature "napt44 or nat64"; type enumeration { enum "eim" { description "endpoint-independent-mapping."; reference "Section 4 of RFC 4787."; } enum "adm" { description "address-dependent-mapping."; reference "Section 4 of RFC 4787."; } enum "edm" { description "address-and-port-dependent-mapping."; reference "Section 4 of RFC 4787."; } } description "Indicates the type of a NAT mapping."; } leaf filtering-type { if-feature "napt44 or nat64"; type enumeration { enum "eif" { description "endpoint-independent-filtering."; reference "Section 5 of RFC 4787."; } enum "adf" { description "address-dependent-filtering."; reference "Section 5 of RFC 4787."; } enum "edf" { description "address-and-port-dependent-filtering"; reference "Section 5 of RFC 4787."; } } description "Indicates the type of a NAT filtering."; } leaf fragment-behavior { if-feature "napt44 or nat64"; type enumeration { enum "drop-all" { description "All received fragments are dropped."; } enum "in-order" { description "Translate fragments only if they are received in order."; } enum "out-of-order" { description "Translate a fragment even if it is received out of order. This behavior is the recommended behavior."; reference "REQ-14 of RFC 4787"; } } description "The fragment behavior instructs the NAT about the behavior to follow to translate fragments received on the external interface of the NAT."; } list port-quota { if-feature "napt44 or nat64"; key quota-type; description "Configures a port quota to be assigned per subscriber. It corresponds to the maximum number of ports to be used by a subscriber."; leaf port-limit { type uint16; description "Configures a port quota to be assigned per subscriber. It corresponds to the maximum number of ports to be used by a subscriber."; reference "REQ-4 of RFC 6888."; } leaf quota-type { type uint8; description "Indicates whether the port quota applies to all protocols (0) or to a specific protocol."; } } container port-set { when "../port-allocation-type = 'port-range-allocation'"; if-feature "napt44 or nat64"; description "Manages port-set assignments."; leaf port-set-size { type uint16; mandatory true; description "Indicates the size of assigned port sets."; } leaf port-set-timeout { type uint32; units "seconds"; description "inactivity timeout for port sets."; } } container timers { if-feature "napt44 or nat64"; description "Configure values of various timeouts."; leaf udp-timeout { type uint32; units "seconds"; default 300; description "UDP inactivity timeout. That is the time a mapping will stay active without packets traversing the NAT."; reference "RFC 4787: Network Address Translation (NAT) Behavioral Requirements for Unicast UDP"; } leaf tcp-idle-timeout { type uint32; units "seconds"; default 7440; description "TCP Idle timeout should be 2 hours and 4 minutes."; reference "RFC 5382: NAT Behavioral Requirements for TCP"; } leaf tcp-trans-open-timeout { type uint32; units "seconds"; default 240; description "The value of the transitory open connection idle-timeout. Section 2.1 of [RFC7857] clarifies that a NAT should provide different configurable parameters for configuring the open and closing idle timeouts. To accommodate deployments that consider a partially open timeout of 4 minutes as being excessive from a security standpoint, a NAT may allow the configured timeout to be less than 4 minutes. However, a minimum default transitory connection idle-timeout of 4 minutes is recommended."; reference "Section 2.1 of RFC 7857."; } leaf tcp-trans-close-timeout { type uint32; units "seconds"; default 240; description "The value of the transitory close connection idle-timeout. Section 2.1 of [RFC7857] clarifies that a NAT should provide different configurable parameters for configuring the open and closing idle timeouts."; reference "Section 2.1 of RFC 7857."; } leaf tcp-in-syn-timeout { type uint32; units "seconds"; default 6; description "A NAT must not respond to an unsolicited inbound SYN packet for at least 6 seconds after the packet is received. If during this interval the NAT receives and translates an outbound SYN for the connection the NAT must silently drop the original unsolicited inbound SYN packet."; reference "RFC 5382 NAT Behavioral Requirements for TCP"; } leaf fragment-min-timeout { when "../../fragment-behavior='out-of-order'"; type uint32; units "seconds"; default 2; description "As long as the NAT has available resources, the NAT allows the fragments to arrive over fragment-min-timeout interval. The default value is inspired from RFC6146."; } leaf icmp-timeout { type uint32; units "seconds"; default 60; description "An ICMP Query session timer must not expire in less than 60 seconds. It is recommended that the ICMP Query session timer be made configurable"; reference "RFC 5508: NAT Behavioral Requirements for ICMP"; } list per-port-timeout { key port-number; description "Some NATs are configurable with short timeouts for some ports, e.g., as 10 seconds on port 53 (DNS) and 123 (NTP) and longer timeouts on other ports."; leaf port-number { type inet:port-number; description "A port number."; } leaf timeout { type uint32; units "seconds"; mandatory true; description "Timeout for this port number"; } } leaf hold-down-timeout { type uint32; units "seconds"; default 120; description "Hold down timer. Ports in the hold down pool are not reassigned until hold-down-timeout expires. The length of time and the maximum number of ports in this state must be configurable by the administrator. This is necessary in order to prevent collisions between old and new mappings and sessions. It ensures that all established sessions are broken instead of redirected to a different peer."; reference "REQ#8 of RFC 6888."; } leaf hold-down-max { type uint32; description "Maximum ports in the Hold down timer pool. Ports in the hold down pool are not reassigned until hold-down-timeout expires. The length of time and the maximum number of ports in this state must be configurable by the administrator. This is necessary in order to prevent collisions between old and new mappings and sessions. It ensures that all established sessions are broken instead of redirected to a different peer."; reference "REQ#8 of RFC 6888."; } } leaf fragments-limit{ when "../fragment-behavior='out-of-order'"; type uint32; description "Limits the number of out of order fragments that can be handled."; reference "Section 11 of RFC 4787."; } list algs { key name; description "ALG-related features."; leaf name { type string; description "The name of the ALG."; } leaf transport-protocol { type uint32; description "The transport protocol used by the ALG (e.g., TCP, UDP)."; } container dst-transport-port { uses port-number; description "The destination port number(s) used by the ALG. For example, - 21 for the FTP ALG - 53 for the DNS ALG."; } container src-transport-port { uses port-number; description "The source port number(s) used by the ALG."; } leaf status { type boolean; description "Enable/disable the ALG."; } } leaf all-algs-enable { type boolean; description "Enable/disable all ALGs. When specified, this parameter overrides the one that may be indicated, eventually, by the 'status' of an individual ALG."; } container notify-pool-usage { if-feature "basic-nat44 or napt44 or nat64"; description "Notification of pool usage when certain criteria are met."; leaf pool-id { type uint32; description "Pool-ID for which the notification criteria is defined"; } leaf high-threshold { type percent; description "Notification must be generated when the defined high threshold is reached. For example, if a notification is required when the pool utilization reaches 90%, this configuration parameter must be set to 90. 0% indicates that no high threshold is enabled."; } leaf low-threshold { type percent; must ". >= ../high-threshold" { error-message "The upper port number must be greater than or equal to lower port number."; } description "Notification must be generated when the defined low threshold is reached. For example, if a notification is required when the pool utilization reaches below 10%, this configuration parameter must be set to 10"; } leaf notify-interval { type uint32 { range "1 .. 3600"; } units "seconds"; default '20'; description "Minimum number of seconds between successive notifications for this pool."; reference "RFC 7659: Definitions of Managed Objects for Network Address Translators (NATs)"; } } container external-realm { description "Identifies the external realm of the NAT instance."; choice realm-type { description "Can be an interface, VRF instance, etc."; case interface { description "External interface."; leaf external-interface { type if:interface-ref; description "Name of the external interface."; } } } } } container mapping-limits { if-feature "napt44 or nat64"; description "Information about the configuration parameters that limits the mappings based upon various criteria."; leaf limit-subscribers { type uint32; description "Maximum number of subscribers that can be serviced by a NAT instance. A subscriber is identified by a given prefix."; reference "RFC 7659: Definitions of Managed Objects for Network Address Translators (NATs)"; } leaf limit-address-mapings { type uint32; description "Maximum number of address mappings that can be handled by a NAT instance. When this limit is reached, packets that would normally trigger translation, will be dropped."; reference "RFC 7659: Definitions of Managed Objects for Network Address Translators (NATs)"; } leaf limit-port-mappings { type uint32; description "Maximum number of port mappings that can be handled by a NAT instance. When this limit is reached, packets that would normally trigger translation, will be dropped."; reference "RFC 7659: Definitions of Managed Objects for Network Address Translators (NATs)"; } list limit-per-protocol { if-feature "napt44 or nat64 or dst-nat"; key protocol-id; description "Configure limits per transport protocol"; leaf protocol-id { type uint8; mandatory true; description "Upper-layer protocol associated with this mapping. Values are taken from the IANA protocol registry: https://www.iana.org/assignments/protocol-numbers/ protocol-numbers.xhtml For example, this field contains 6 (TCP) for a TCP mapping or 17 (UDP) for a UDP mapping."; } leaf limit { type uint32; description "Maximum number of protocol-specific NAT mappings per instance."; } } } container connection-limits { if-feature "basic-nat44 or napt44 or nat64"; description "Information about the configuration parameters that rate limit the translation based upon various criteria."; leaf limit-per-subscriber { type uint32; units "bits/second"; description "Rate-limit the number of new mappings and sessions per subscriber."; } leaf limit-per-instance { type uint32; units "bits/second"; mandatory true; description "Rate-limit the number of new mappings and sessions per instance."; } list limit-per-protocol { if-feature "napt44 or nat64"; key protocol-id; description "Configure limits per transport protocol"; leaf protocol-id { type uint8; mandatory true; description "Upper-layer protocol associated with this mapping. Values are taken from the IANA protocol registry: https://www.iana.org/assignments/protocol-numbers/ protocol-numbers.xhtml For example, this field contains 6 (TCP) for a TCP mapping or 17 (UDP) for a UDP mapping."; } leaf limit { type uint32; description "Rate-limit the number of protocol-specific mappings and sessions per instance."; } } } container notification-limits { description "Sets notification limits."; leaf notify-interval { if-feature "basic-nat44 or napt44 or nat64"; type uint32 { range "1 .. 3600"; } units "seconds"; default '10'; description "Minimum number of seconds between successive notifications for this NAT instance."; reference "RFC 7659: Definitions of Managed Objects for Network Address Translators (NATs)"; } leaf notify-addresses-usage { if-feature "basic-nat44 or napt44 or nat64"; type percent; description "Notification of address mappings usage over the whole NAT instance. Notification must be generated when the defined threshold is reached. For example, if a notification is required when the address mappings utilization reaches 90%, this configuration parameter must be set to 90."; } leaf notify-ports-usage { if-feature "napt44 or nat64"; type percent; description "Notification of port mappings usage over the whole NAT instance. Notification must be generated when the defined threshold is reached. For example, if a notification is required when the port mappings utilization reaches 90%, this configuration parameter must be set to 90."; } leaf notify-subscribers-limit { if-feature "basic-nat44 or napt44 or nat64"; type uint32; description "Notification of active subscribers per NAT instance. Notification must be generated when the defined threshold is reached."; } } leaf logging-enable { if-feature "basic-nat44 or napt44 or nat64"; type boolean; description "Enable logging features."; reference "Section 2.3 of RFC 6908 and REQ-12 of RFC6888."; } container mapping-table { if-feature "basic-nat44 or napt44 " + "or nat64 or clat or dst-nat"; description "NAT mapping table. Applicable for functions which maintain static and/or dynamic mappings, such as NAT44, Destination NAT, NAT64, or CLAT."; list mapping-entry { key "index"; description "NAT mapping entry."; uses mapping-entry; } } container statistics { config false; description "Statistics related to the NAT instance."; leaf discontinuity-time { type yang:date-and-time; mandatory true; description "The time on the most recent occasion at which the NAT instance suffered a discontinuity. This must be initialized when the NAT instance is configured or rebooted."; } container traffic-statistics { description "Generic traffic statistics."; leaf sent-packets { type yang:zero-based-counter64; description "Number of packets sent."; } leaf sent-bytes { type yang:zero-based-counter64; units 'bytes'; description "Counter for sent traffic in bytes."; } leaf rcvd-packets { type yang:zero-based-counter64; description "Number of received packets."; } leaf rcvd-bytes { type yang:zero-based-counter64; units 'bytes'; description "Counter for received traffic in bytes."; } leaf dropped-packets { type yang:zero-based-counter64; description "Number of dropped packets."; } leaf dropped-bytes { type yang:zero-based-counter64; units 'bytes'; description "Counter for dropped traffic in bytes."; } leaf dropped-fragments { if-feature "napt44 or nat64"; type yang:zero-based-counter64; description "Number of dropped fragments on the external realm."; } leaf dropped-address-limit-packets { if-feature "basic-nat44 or napt44 or nat64"; type yang:zero-based-counter64; description "Number of dropped packets because an address limit is reached."; } leaf dropped-address-limit-bytes { if-feature "basic-nat44 or napt44 or nat64"; type yang:zero-based-counter64; units 'bytes'; description "Counter of dropped packets because an address limit is reached, in bytes."; } leaf dropped-address-packets { if-feature "basic-nat44 or napt44 or nat64"; type yang:zero-based-counter64; description "Number of dropped packets because no address is available for allocation."; } leaf dropped-address-bytes { if-feature "basic-nat44 or napt44 or nat64"; type yang:zero-based-counter64; units 'bytes'; description "Counter of dropped packets because no address is available for allocation, in bytes."; } leaf dropped-port-limit-packets { if-feature "napt44 or nat64"; type yang:zero-based-counter64; description "Number of dropped packets because a port limit is reached."; } leaf dropped-port-limit-bytes { if-feature "napt44 or nat64"; type yang:zero-based-counter64; units 'bytes'; description "Counter of dropped packets because a port limit is reached, in bytes."; } leaf dropped-port-packets { if-feature "napt44 or nat64"; type yang:zero-based-counter64; description "Number of dropped packets because no port is available for allocation."; } leaf dropped-port-bytes { if-feature "napt44 or nat64"; type yang:zero-based-counter64; units 'bytes'; description "Counter of dropped packets because no port is available for allocation, in bytes."; } leaf dropped-subscriber-limit-packets { if-feature "basic-nat44 or napt44 or nat64"; type yang:zero-based-counter64; description "Number of dropped packets because the subscriber limit per instance is reached."; } leaf dropped-subscriber-limit-bytes { if-feature "basic-nat44 or napt44 or nat64"; type yang:zero-based-counter64; units 'bytes'; description "Counter of dropped packets because the subscriber limit per instance is reached, in bytes."; } } container mappings-statistics { description "Mappings statistics."; leaf total-active-subscribers { if-feature "basic-nat44 or napt44 or nat64"; type yang:gauge32; description "Total number of active subscribers (that is, subscribers for which the NAT maintains active mappings. A subscriber is identified by a subnet, subscriber-mask, etc."; } leaf total-address-mappings { if-feature "basic-nat44 or napt44 " + "or nat64 or clat or dst-nat"; type yang:gauge32; description "Total number of address mappings present at a given time. It includes both static and dynamic mappings."; reference "Section 3.3.8 of RFC 7659"; } leaf total-port-mappings { if-feature "napt44 or nat64"; type yang:gauge32; description "Total number of NAT port mappings present at a given time. It includes both static and dynamic mappings."; reference "Section 3.3.9 of RFC 7659"; } list total-per-protocol { if-feature "napt44 or nat64"; key protocol-id; description "Total mappings for each enabled/supported protocol."; leaf protocol-id { type uint8; mandatory true; description "Upper-layer protocol associated with this mapping. For example, this field contains 6 (TCP) for a TCP mapping or 17 (UDP) for a UDP mapping."; } leaf total { type yang:gauge32; description "Total number of a protocol-specific mappings present at a given time. The protocol is identified by protocol-id."; } } } container pools-stats { if-feature "basic-nat44 or napt44 or nat64"; description "Statistics related to address/prefix pools usage"; leaf addresses-allocated { type yang:gauge32; description "Number of all allocated addresses."; } leaf addresses-free { type yang:gauge32; description "Number of unallocated addresses of all pools at a given time. The sum of unallocated and allocated addresses is the total number of addresses of the pools."; } container ports-stats { if-feature "napt44 or nat64"; description "Statistics related to port numbers usage."; leaf ports-allocated { type yang:gauge32; description "Number of allocated ports from all pools."; } leaf ports-free { type yang:gauge32; description "Number of unallocated addresses from all pools."; } } list per-pool-stats { if-feature "basic-nat44 or napt44 or nat64"; key "pool-id"; description "Statistics related to address/prefix pool usage"; leaf pool-id { type uint32; description "Unique Identifier that represents a pool of addresses/prefixes."; } leaf discontinuity-time { type yang:date-and-time; mandatory true; description "The time on the most recent occasion at which this pool counters suffered a discontinuity. This must be initialized when the address pool is configured."; } container pool-stats { description "Statistics related to address/prefix pool usage"; leaf addresses-allocated { type yang:gauge32; description "Number of allocated addresses from this pool."; } leaf addresses-free { type yang:gauge32; description "Number of unallocated addresses in this pool."; } } container port-stats { if-feature "napt44 or nat64"; description "Statistics related to port numbers usage."; leaf ports-allocated { type yang:gauge32; description "Number of allocated ports from this pool."; } leaf ports-free { type yang:gauge32; description "Number of unallocated addresses from this pool."; } } } } } } } } /* * Notifications */ notification nat-pool-event { if-feature "basic-nat44 or napt44 or nat64"; description "Notifications must be generated when the defined high/low threshold is reached. Related configuration parameters must be provided to trigger the notifications."; leaf id { type leafref { path "/nat/instances/instance/id"; } mandatory true; description "NAT instance Identifier."; } leaf policy-id { type leafref { path "/nat/instances/instance/policy/id"; } description "Policy Identifier."; } leaf pool-id { type leafref { path "/nat/instances/instance/policy/" + "external-ip-address-pool/pool-id"; } mandatory true; description "Pool Identifier."; } leaf notify-pool-threshold { type percent; mandatory true; description "A threshold (high-threshold or low-threshold) has been fired."; } } notification nat-instance-event { if-feature "basic-nat44 or napt44 or nat64"; description "Notifications must be generated when notify-addresses-usage and/or notify-ports-usage threshold are reached."; leaf id { type leafref { path "/nat/instances/instance/id"; } mandatory true; description "NAT instance Identifier."; } leaf notify-subscribers-threshold { type uint32; description "The notify-subscribers-limit threshold has been fired."; } leaf notify-addresses-threshold { type percent; description "The notify-addresses-usage threshold has been fired."; } leaf notify-ports-threshold { type percent; description "The notify-ports-usage threshold has been fired."; } } }