I2NSF Working Group J. Kim, Ed. Internet-Draft J. Jeong, Ed. Intended status: Standards Track Sungkyunkwan University Expires: 7 April 2022 J. Park ETRI S. Hares Q. Lin Huawei 4 October 2021 I2NSF Network Security Function-Facing Interface YANG Data Model draft-ietf-i2nsf-nsf-facing-interface-dm-15 Abstract This document defines a YANG data model for configuring security policy rules on Network Security Functions (NSF) in the Interface to Network Security Functions (I2NSF) framework. The YANG data model in this document corresponds to the information model for NSF-Facing Interface in the I2NSF framework. Status of This Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at https://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." This Internet-Draft will expire on 7 April 2022. Copyright Notice Copyright (c) 2021 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (https://trustee.ietf.org/ license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights Kim, et al. Expires 7 April 2022 [Page 1] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. YANG Tree Diagram . . . . . . . . . . . . . . . . . . . . . . 3 3.1. General I2NSF Security Policy Rule . . . . . . . . . . . 3 3.2. Event Clause . . . . . . . . . . . . . . . . . . . . . . 5 3.3. Condition Clause . . . . . . . . . . . . . . . . . . . . 6 3.4. Action Clause . . . . . . . . . . . . . . . . . . . . . . 11 4. YANG Data Model of NSF-Facing Interface . . . . . . . . . . . 12 4.1. YANG Module of NSF-Facing Interface . . . . . . . . . . . 13 5. XML Configuration Examples of Low-Level Security Policy Rules . . . . . . . . . . . . . . . . . . . . . . . . . . 65 5.1. Security Requirement 1: Block Social Networking Service (SNS) Access during Business Hours . . . . . . . . . . . 65 5.2. Security Requirement 2: Block Malicious VoIP/VoLTE Packets Coming to a Company . . . . . . . . . . . . . . . . . . . 69 5.3. Security Requirement 3: Mitigate HTTP and HTTPS Flood Attacks on a Company Web Server . . . . . . . . . . . . . 72 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 75 7. Security Considerations . . . . . . . . . . . . . . . . . . . 75 8. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 76 9. Contributors . . . . . . . . . . . . . . . . . . . . . . . . 76 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 77 10.1. Normative References . . . . . . . . . . . . . . . . . . 77 10.2. Informative References . . . . . . . . . . . . . . . . . 80 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 81 1. Introduction This document defines a YANG [RFC6020][RFC7950] data model for security policy rule configuration of Network Security Functions (NSF). The YANG data model in this document is based on the information and data model in [I-D.ietf-i2nsf-capability-data-model] for the NSF-Facing Interface in the Interface to Network Security Functions (I2NSF) architecture [RFC8329]. The YANG data model in this document focuses on security policy configuration for the NSFs discussed in [I-D.ietf-i2nsf-capability-data-model], i.e., generic NSF (. This YANG data model uses an "Event-Condition-Action" (ECA) policy model that is used as the basis for the design of I2NSF Policy described in [RFC8329] and [I-D.ietf-i2nsf-capability-data-model]. Kim, et al. Expires 7 April 2022 [Page 2] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 The "ietf-i2nsf-policy-rule-for-nsf" YANG module defined in this document provides the configuration of the following features. * A security policy rule of a network security function. * An event clause of a generic network security function. * A condition clause of a generic network security function. * An action clause of a generic network security function. 2. Terminology The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in BCP 14 [RFC2119] [RFC8174] when, and only when, they appear in all capitals, as shown here. This document uses the terminology described in [RFC8329]. This document follows the guidelines of [RFC8407], uses the common YANG types defined in [RFC6991], and adopts the Network Management Datastore Architecture (NMDA). The meaning of the symbols in tree diagrams is defined in [RFC8340]. 3. YANG Tree Diagram This section shows a YANG tree diagram of policy for network security functions. [I-D.ietf-i2nsf-capability-data-model]. 3.1. General I2NSF Security Policy Rule This section shows a YANG tree diagram for a general I2NSF security policy rule for generic network security functions. Kim, et al. Expires 7 April 2022 [Page 3] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 module: ietf-i2nsf-policy-rule-for-nsf +--rw i2nsf-security-policy* [system-policy-name] +--rw system-policy-name string +--rw priority-usage? identityref +--rw resolution-strategy? identityref +--rw default-action? identityref +--rw rules* [rule-name] | +--rw rule-name string | +--rw rule-description? string | +--rw rule-priority? uint8 | +--rw rule-enable? boolean | +--rw session-aging-time? uint16 | +--rw long-connection | | +--rw enable? boolean | | +--rw duration? uint16 | +--rw event | ... | +--rw action | ... +--rw rule-group +--rw groups* [group-name] +--rw group-name string +--rw rule-range | +--rw start-rule? string | +--rw end-rule? string +--rw enable? boolean +--rw description? string Figure 1: YANG Tree Diagram for Network Security Policy The system policy provides for multiple system policies in one NSF, and each system policy is used by one virtual instance of the NSF/ device. The system policy includes system policy name, priority usage, resolution strategy, default action, and rules. A resolution strategy is used to decide how to resolve conflicts that occur between the actions of the same or different policy rules that are matched and contained in a particular NSF. The resolution strategy is defined as First Matching Rule (FMR), Last Matching Rule (LMR), Prioritized Matching Rule (PMR) with Errors (PMRE), and Prioritized Matching Rule with No Errors (PMRN). The resolution strategy can be extended according to specific vendor action features. The resolution strategy is described in detail in [I-D.ietf-i2nsf-capability-data-model]. Kim, et al. Expires 7 April 2022 [Page 4] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 A default action is used to execute I2NSF policy rule when no rule matches a packet. The default action is defined as pass, drop, rate- limit, and mirror. The default action can be extended according to specific vendor action features. The default action is described in detail in [I-D.ietf-i2nsf-capability-data-model]. The rules include rule name, rule description, rule priority, rule enable, event, condition, and action. 3.2. Event Clause This section shows a YANG tree diagram for an event clause for a general I2NSF security policy rule for generic network security functions. module: ietf-i2nsf-policy-rule-for-nsf +--rw i2nsf-security-policy* [system-policy-name] ... +--rw rules* [rule-name] | ... | +--rw event | | +--rw event-clause-description? string | | +--rw time | | | +--rw start-date-time? yang:date-and-time | | | +--rw end-date-time? yang:date-and-time | | | +--rw period | | | | +--rw start-time? time | | | | +--rw end-time? time | | | | +--rw day* identityref | | | | +--rw date* int32 | | | | +--rw month* string | | | +--rw frequency? enumeration | | +--rw event-clauses | | +--rw system-event* identityref | | +--rw system-alarm* identityref | +--rw condition | | ... | +--rw action | ... +--rw rule-group ... Figure 2: YANG Tree Diagram for an Event Clause An event clause is any important occurrence at a specific time of a change in the system being managed, and/or in the environment of the system being managed. An event clause is used to trigger the evaluation of the condition clause of the I2NSF Policy Rule. The Kim, et al. Expires 7 April 2022 [Page 5] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 event clause is defined as a system event, system alarm [I-D.ietf-i2nsf-nsf-monitoring-data-model] and time. The event clause can be extended according to specific vendor event features. The event clause is described in detail in [I-D.ietf-i2nsf-capability-data-model]. 3.3. Condition Clause This section shows a YANG tree diagram for a condition clause for a general I2NSF security policy rule for generic network security functions. module: ietf-i2nsf-policy-rule-for-nsf +--rw i2nsf-security-policy* [system-policy-name] ... +--rw rules* [rule-name] | ... | +--rw event | ... | +--rw condition | | +--rw condition-clause-description? string | | +--rw ethernet | | | +--rw ethernet-description? string | | | +--rw source-address* yang:mac-address | | | +--rw destination-address* yang:mac-address | | | +--rw ether-type* uint16 | | +--rw ipv4 | | | +--rw description? string | | | +--rw header-length* [start end] | | | | +--rw start uint8 | | | | +--rw end uint8 | | | +--rw dscp* inet:dscp | | | +--rw total-length* [start end] | | | | +--rw start uint16 | | | | +--rw end uint16 | | | +--rw identification* uint16 | | | +--rw fragment-flags* identityref | | | +--rw fragment-offset* [start end] | | | | +--rw start uint16 | | | | +--rw end uint16 | | | +--rw ttl* [start end] | | | | +--rw start uint8 | | | | +--rw end uint8 | | | +--rw protocol* uint8 | | | +--rw source-address | | | | +--rw (match-type)? | | | | +--:(prefix) | | | | | +--rw ipv4-prefix* [ipv4] Kim, et al. Expires 7 April 2022 [Page 6] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 | | | | | +--rw ipv4 inet:ipv4-address-no-zone | | | | | +--rw (subnet)? | | | | | +--:(prefix-length) | | | | | | +--rw prefix-length? uint8 | | | | | +--:(netmask) | | | | | +--rw netmask? yang:dotted-quad | | | | +--:(range) | | | | +--rw ipv4-range* [start end] | | | | +--rw start inet:ipv4-address-no-zone | | | | +--rw end inet:ipv4-address-no-zone | | | +--rw destination-address | | | | +--rw (match-type)? | | | | +--:(prefix) | | | | | +--rw ipv4-prefix* [ipv4] | | | | | +--rw ipv4 inet:ipv4-address-no-zone | | | | | +--rw (subnet)? | | | | | +--:(prefix-length) | | | | | | +--rw prefix-length? uint8 | | | | | +--:(netmask) | | | | | +--rw netmask? yang:dotted-quad | | | | +--:(range) | | | | +--rw ipv4-range* [start end] | | | | +--rw start inet:ipv4-address-no-zone | | | | +--rw end inet:ipv4-address-no-zone | | | +--rw ipopts* identityref | | +--rw ipv6 | | | +--rw description? string | | | +--rw dscp* inet:dscp | | | +--rw flow-label* [start end] | | | | +--rw start inet:ipv6-flow-label | | | | +--rw end inet:ipv6-flow-label | | | +--rw payload-length* [start end] | | | | +--rw start uint16 | | | | +--rw end uint16 | | | +--rw next-header* uint8 | | | +--rw hop-limit* [start end] | | | | +--rw start uint8 | | | | +--rw end uint8 | | | +--rw source-address | | | | +--rw (match-type)? | | | | +--:(prefix) | | | | | +--rw ipv6-prefix* [ipv6] | | | | | +--rw ipv6 inet:ipv6-address-no-zone | | | | | +--rw prefix-length? uint8 | | | | +--:(range) | | | | +--rw ipv6-range* [start end] | | | | +--rw start inet:ipv6-address-no-zone | | | | +--rw end inet:ipv6-address-no-zone Kim, et al. Expires 7 April 2022 [Page 7] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 | | | +--rw destination-address | | | +--rw (match-type)? | | | +--:(prefix) | | | | +--rw ipv6-prefix* [ipv6] | | | | +--rw ipv6 inet:ipv6-address-no-zone | | | | +--rw prefix-length? uint8 | | | +--:(range) | | | +--rw ipv6-range* [start end] | | | +--rw start inet:ipv6-address-no-zone | | | +--rw end inet:ipv6-address-no-zone | | +--rw tcp | | | +--rw description? string | | | +--rw source-port-number* [start end] | | | | +--rw start inet:port-number | | | | +--rw end inet:port-number | | | +--rw destination-port-number* [start end] | | | | +--rw start inet:port-number | | | | +--rw end inet:port-number | | | +--rw flags* identityref | | +--rw udp | | | +--rw description? string | | | +--rw source-port-number | | | | +--rw start? inet:port-number | | | | +--rw end? inet:port-number | | | +--rw destination-port-number | | | | +--rw start? inet:port-number | | | | +--rw end? inet:port-number | | | +--rw total-length* [start end] | | | +--rw start uint32 | | | +--rw end uint32 | | +--rw sctp | | | +--rw description? string | | | +--rw source-port-number | | | | +--rw start? inet:port-number | | | | +--rw end? inet:port-number | | | +--rw destination-port-number | | | | +--rw start? inet:port-number | | | | +--rw end? inet:port-number | | | +--rw verification-tag* uint32 | | | +--rw chunk-type* uint8 | | +--rw dccp | | | +--rw description? string | | | +--rw source-port-number | | | | +--rw start? inet:port-number | | | | +--rw end? inet:port-number | | | +--rw destination-port-number | | | | +--rw start? inet:port-number | | | | +--rw end? inet:port-number Kim, et al. Expires 7 April 2022 [Page 8] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 | | | +--rw service-code* uint32 | | +--rw icmp* [version] | | | +--rw description? string | | | +--rw version enumeration | | | +--rw type* uint8 | | | +--rw code* uint8 | | +--rw url-category | | | +--rw description? string | | | +--rw pre-defined-category* string | | | +--rw user-defined-category* string | | +--rw voice | | | +--rw description? string | | | +--rw source-voice-id* string | | | +--rw destination-voice-id* string | | | +--rw user-agent* string | | +--rw ddos | | | +--rw description? string | | | +--rw alert-packet-rate? uint32 | | | +--rw alert-flow-rate? uint32 | | | +--rw alert-byte-rate? uint32 | | +--rw anti-virus | | | +--rw profile* string | | | +--rw exception-files* string | | +--rw payload | | | +--rw packet-payload-description? string | | | +--rw payload-content* string | | +--rw context | | +--rw context-description? string | | +--rw application | | | +--rw description? string | | | +--rw object* string | | | +--rw group* string | | | +--rw label* string | | | +--rw category | | | +--rw application-category* [name subcategory] | | | +--rw name string | | | +--rw subcategory string | | +--rw target | | | +--rw description? string | | | +--rw device* identityref | | +--rw users | | | +--rw users-description? string | | | +--rw user* [user-id] | | | | +--rw user-id uint32 | | | | +--rw user-name? string | | | +--rw group* [group-id] | | | | +--rw group-id uint32 | | | | +--rw group-name? string Kim, et al. Expires 7 April 2022 [Page 9] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 | | | +--rw security-group? string | | +--rw geography-location | | +--rw description? string | | +--rw source* string | | +--rw destination* string | +--rw action | ... +--rw rule-group ... Figure 3: YANG Tree Diagram for a Condition Clause A condition clause is defined as a set of attributes, features, and/ or values that are to be compared with a set of known attributes, features, and/or values in order to determine whether or not the set of actions in that (imperative) I2NSF policy rule can be executed or not. A condition clause is classified as a condition of generic network security functions, advanced network security functions, or context. A condition clause of generic network security functions is defined as IPv4 condition, IPv6 condition, TCP condition, UDP condition, SCTP condition, DCCP condition, and ICMP (ICMPv4 and ICMPv6) condition. Note that the data model in this document does not focus on only IP addresses, but focuses on all the fields of IPv4 and IPv6 headers. The IPv4 and IPv6 headers have similarity with some different fields. In this case, it is better to handle separately the IPv4 and IPv6 headers such that the different fields can be used to handle IPv4 and IPv6 packets. A condition clause of advanced network security functions is defined as url category condition, voice condition, DDoS condition, or payload condition. A condition clause of context is defined as application condition, target condition, users condition, and geography condition. Note that this document deals only with conditions of several advanced network security functions such as url filter (i.e., web filter), VoIP/VoLTE security, and DDoS-attack mitigator. A condition clause of other advanced network security functions such as Intrusion Prevention System (IPS) and Data Loss Prevention (DLP) can be defined as an extension in future. A condition clause can be extended according to specific vendor condition features. A condition clause is described in detail in [I-D.ietf-i2nsf-capability-data-model]. Kim, et al. Expires 7 April 2022 [Page 10] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 3.4. Action Clause This section shows a YANG tree diagram for an action clause for a general I2NSF security policy rule for generic network security functions. module: ietf-i2nsf-policy-rule-for-nsf +--rw i2nsf-security-policy* [system-policy-name] ... +--rw rules* [rule-name] | ... | +--rw event | ... | +--rw condition | ... | +--rw action | +--rw action-clause-description? string | +--rw packet-action | | +--rw ingress-action? identityref | | +--rw egress-action? identityref | | +--rw log-action? identityref | +--rw flow-action | | +--rw ingress-action? identityref | | +--rw egress-action? identityref | | +--rw log-action? identityref | +--rw advanced-action | +--rw content-security-control* identityref | +--rw attack-mitigation-control* identityref +--rw rule-group ... Figure 4: YANG Tree Diagram for an Action Clause Kim, et al. Expires 7 April 2022 [Page 11] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 An action is used to control and monitor aspects of flow-based NSFs when the policy rule event and condition clauses are satisfied. NSFs provide security services by executing various actions. The action clause is defined as ingress action, egress action, or log action for packet action, flow action, and advanced action for additional inspection. The packet action is an action for an individual packet such as an IP datagram as a stateless process that uses the packet's header and payload. The flow action is an action of a traffic flow such as the packets of a TCP session (e.g., an HTTP/HTTPS session) as a stateful process that uses the traffic flow information such as 5-tuple information, packet counts, and byte counts. The advanced action is an action for an advanced security service (e.g., url filter, DDoS-attack mitigator, and VoIP/VoLTE filter) for either a packet or a traffic flow according to the intention of such an advanced security service. The action clause can be extended according to specific vendor action features. The action clause is described in detail in [I-D.ietf-i2nsf-capability-data-model]. 4. YANG Data Model of NSF-Facing Interface The main objective of this data model is to provide both an information model and the corresponding YANG data model of I2NSF NSF- Facing Interface. This interface can be used to deliver control and management messages between Security Controller and NSFs for the I2NSF low-level security policies. This data model is designed to support the I2NSF framework that can be extended according to the security needs. In other words, the model design is independent of the content and meaning of specific policies as well as the implementation approach. With the YANG data model of I2NSF NSF-Facing Interface, this document suggests use cases for security policy rules such as time-based firewall, web filter, VoIP/VoLTE security service, and DDoS-attack mitigation in Section 5. Kim, et al. Expires 7 April 2022 [Page 12] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 4.1. YANG Module of NSF-Facing Interface This section describes a YANG module of NSF-Facing Interface. This document provides identities in the data model for the configuration of an NSF. The identity has the same concept with the corresponding identity in [I-D.ietf-i2nsf-consumer-facing-interface-dm] This YANG module imports from [RFC6991]. It makes references to [RFC0768] [RFC0791] [RFC0792] [RFC2474] [RFC3261] [RFC4340] [RFC4443] [RFC4960] [RFC5595] [RFC6335] [RFC8200] [RFC8329] [RFC8335] [RFC8344] [IEEE-802.3] [ISO-Country-Codes] [IANA-Protocol-Numbers] [IANA-ICMP-Parameters] [I-D.ietf-tcpm-rfc793bis] [I-D.ietf-i2nsf-capability-data-model] [I-D.ietf-i2nsf-nsf-monitoring-data-model]. file "ietf-i2nsf-policy-rule-for-nsf@2021-10-04.yang" module ietf-i2nsf-policy-rule-for-nsf { yang-version 1.1; namespace "urn:ietf:params:xml:ns:yang:ietf-i2nsf-policy-rule-for-nsf"; prefix nsfintf; import ietf-inet-types{ prefix inet; reference "Section 4 of RFC 6991"; } import ietf-yang-types { prefix yang; reference "Section 3 of RFC 6991"; } organization "IETF I2NSF (Interface to Network Security Functions) Working Group"; contact "WG Web: WG List: Editor: Jinyong Tim Kim Editor: Jaehoon Paul Jeong "; description Kim, et al. Expires 7 April 2022 [Page 13] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 "This module is a YANG module for Network Security Functions (NSF)-Facing Interface. The key words 'MUST', 'MUST NOT', 'REQUIRED', 'SHALL', 'SHALL NOT', 'SHOULD', 'SHOULD NOT', 'RECOMMENDED', 'NOT RECOMMENDED', 'MAY', and 'OPTIONAL' in this document are to be interpreted as described in BCP 14 (RFC 2119) (RFC 8174) when, and only when, they appear in all capitals, as shown here. Copyright (c) 2021 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 (https://trustee.ietf.org/license-info). This version of this YANG module is part of RFC XXXX (https://www.rfc-editor.org/info/rfcXXXX); see the RFC itself for full legal notices."; revision "2021-10-04"{ description "The latest revision."; reference "RFC XXXX: I2NSF Network Security Function-Facing Interface YANG Data Model"; } /* * Identities */ identity priority-usage { description "Base identity for priority usage type."; } identity priority-by-order { base priority-usage; description "Identity for priority by order"; } identity priority-by-number { base priority-usage; Kim, et al. Expires 7 April 2022 [Page 14] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 description "Identity for priority by number"; } identity event { description "Base identity for policy events"; reference "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF Monitoring YANG Data Model - Event"; } identity system-event { base event; description "Identity for system events"; reference "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF Monitoring YANG Data Model - System event"; } identity system-alarm { base event; description "Identity for system alarms"; reference "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF Monitoring YANG Data Model - System alarm"; } identity access-violation { base system-event; description "Identity for access violation system events"; reference "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF Monitoring YANG Data Model - System event for access violation"; } identity configuration-change { base system-event; description "Identity for configuration change system events"; reference "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF Kim, et al. Expires 7 April 2022 [Page 15] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 Monitoring YANG Data Model - System event for configuration change"; } identity memory-alarm { base system-alarm; description "Identity for memory alarm system alarms"; reference "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF Monitoring YANG Data Model - System alarm for memory"; } identity cpu-alarm { base system-alarm; description "Identity for CPU alarm system alarms"; reference "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF Monitoring YANG Data Model - System alarm for CPU"; } identity disk-alarm { base system-alarm; description "Identity for disk alarm system alarms"; reference "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF Monitoring YANG Data Model - System alarm for disk"; } identity hardware-alarm { base system-alarm; description "Identity for hardware alarm system alarms"; reference "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF Monitoring YANG Data Model - System alarm for hardware"; } identity interface-alarm { base system-alarm; description "Identity for interface alarm Kim, et al. Expires 7 April 2022 [Page 16] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 system alarms"; reference "draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF Monitoring YANG Data Model - System alarm for interface"; } identity fragmentation-flags { description "Base identity for fragmentation flags type"; reference "RFC 791: Internet Protocol - Fragmentation Flags"; } identity fragment { base fragmentation-flags; description "Identity for 'More fragment' flag"; reference "RFC 791: Internet Protocol - Fragmentation Flags"; } identity no-fragment { base fragmentation-flags; description "Identity for 'Do not fragment' flag"; reference "RFC 791: Internet Protocol - Fragmentation Flags"; } identity reserved { base fragmentation-flags; description "Identity for reserved flags"; reference "RFC 791: Internet Protocol - Fragmentation Flags"; } identity ipopts { description "Base identity for IP options"; reference "RFC 791: Internet Protocol - Options"; } identity rr { base ipopts; description "Identity for 'Record Route' IP Option"; Kim, et al. Expires 7 April 2022 [Page 17] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 reference "RFC 791: Internet Protocol - Options"; } identity eol { base ipopts; description "Identity for 'End of List' IP Option"; reference "RFC 791: Internet Protocol - Options"; } identity nop { base ipopts; description "Identity for 'No Operation' IP Option"; reference "RFC 791: Internet Protocol - Options"; } identity ts { base ipopts; description "Identity for 'Timestamp' IP Option"; reference "RFC 791: Internet Protocol - Options"; } identity sec { base ipopts; description "Identity for 'IP security' IP Option"; reference "RFC 791: Internet Protocol - Options"; } identity esec { base ipopts; description "Identity for 'IP extended security' IP Option"; reference "RFC 791: Internet Protocol - Options"; } identity lsrr { base ipopts; description "Identity for 'Loose Source Routing' IP Option"; Kim, et al. Expires 7 April 2022 [Page 18] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 reference "RFC 791: Internet Protocol - Options"; } identity ssrr { base ipopts; description "Identity for 'Strict Source Routing' IP Option"; reference "RFC 791: Internet Protocol - Options"; } identity satid { base ipopts; description "Identity for 'Stream Identifier' IP Option"; reference "RFC 791: Internet Protocol - Options"; } identity any { base ipopts; description "Identity for 'any IP options included in IPv4 packet"; reference "RFC 791: Internet Protocol - Options"; } identity tcp-flags { description "Base identity for TCP flags"; reference "draft-ietf-tcpm-rfc793bis-25: Transmission Control Protocol (TCP) Specification - TCP Header Flags RFC 3168: The Addition of Explicit Congestion Notification (ECN) to IP - ECN-Echo (ECE) Flag and Congestion Window Reduced (CWR) Flag draft-ietf-tcpm-accurate-ecn-15: More Accurate ECN Feedback in TCP - ECN-Echo (ECE) Flag and Congestion Window Reduced (CWR) Flag"; } identity cwr { base tcp-flags; description "Identity for 'Congestion Window Reduced' TCP flag"; reference Kim, et al. Expires 7 April 2022 [Page 19] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 "draft-ietf-tcpm-rfc793bis-25: Transmission Control Protocol (TCP) Specification - TCP Header Flags RFC 3168: The Addition of Explicit Congestion Notification (ECN) to IP - ECN-Echo (ECE) Flag and Congestion Window Reduced (CWR) Flag draft-ietf-tcpm-accurate-ecn-15: More Accurate ECN Feedback in TCP - ECN-Echo (ECE) Flag and Congestion Window Reduced (CWR) Flag"; } identity ece { base tcp-flags; description "Identity for 'Explicit Congestion Notification-Echo' TCP flag"; reference "draft-ietf-tcpm-rfc793bis-25: Transmission Control Protocol (TCP) Specification - TCP Header Flags RFC 3168: The Addition of Explicit Congestion Notification (ECN) to IP - ECN-Echo (ECE) Flag and Congestion Window Reduced (CWR) Flag draft-ietf-tcpm-accurate-ecn-15: More Accurate ECN Feedback in TCP - ECN-Echo (ECE) Flag and Congestion Window Reduced (CWR) Flag"; } identity urg { base tcp-flags; description "Identity for 'Urgent' TCP flag"; reference "draft-ietf-tcpm-rfc793bis-25: Transmission Control Protocol (TCP) Specification - Flags"; } identity ack { base tcp-flags; description "Identity for 'acknowledgement' TCP flag"; reference "draft-ietf-tcpm-rfc793bis-25: Transmission Control Protocol (TCP) Specification - Flags"; } identity psh { base tcp-flags; description "Identity for 'Push' TCP flag"; Kim, et al. Expires 7 April 2022 [Page 20] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 reference "draft-ietf-tcpm-rfc793bis-25: Transmission Control Protocol (TCP) Specification - Flags"; } identity rst { base tcp-flags; description "Identity for 'Reset' TCP flag"; reference "draft-ietf-tcpm-rfc793bis-25: Transmission Control Protocol (TCP) Specification - Flags"; } identity syn { base tcp-flags; description "Identity for 'Synchronize' TCP flag"; reference "draft-ietf-tcpm-rfc793bis-25: Transmission Control Protocol (TCP) Specification - Flags"; } identity fin { base tcp-flags; description "Identity for 'Finish' TCP flag"; reference "draft-ietf-tcpm-rfc793bis-25: Transmission Control Protocol (TCP) Specification - Flags"; } identity target-device { description "Base identity for target devices"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model"; } identity computer { base target-device; description "Identity for computer such as personal computer (PC) and server"; } identity mobile-phone { Kim, et al. Expires 7 April 2022 [Page 21] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 base target-device; description "Identity for mobile-phone such as smartphone and cellphone"; } identity voip-volte-phone { base target-device; description "Identity for voip-volte-phone"; } identity tablet { base target-device; description "Identity for tablet"; } identity network-infrastructure-device { base target-device; description "Identity for network infrastructure devices such as switch, router, and access point"; } identity iot-device { base target-device; description "Identity for IoT (Internet of Things) devices"; } identity ot { base target-device; description "Identity for Operational Technology"; } identity vehicle { base target-device; description "Identity for vehicle that connects to and shares data through the Internet"; } identity advanced-nsf { description "Base identity for advanced Network Security Function (NSF) capability. This can be used for advanced NSFs such as Kim, et al. Expires 7 April 2022 [Page 22] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 Anti-DDoS Attack, IPS, URL-Filtering, Antivirus, and VoIP/VoLTE Filter."; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model"; } identity content-security-control { base advanced-nsf; description "Base identity for content security control"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model"; } identity ips { base content-security-control; description "Identity for IPS (Intrusion Prevention System) that prevents malicious activity within a network"; } identity url-filtering { base content-security-control; description "Identity for url filtering that limits access by comparing the web traffic's URL with the URLs for web filtering in a database"; } identity anti-virus { base content-security-control; description "Identity for antivirus to protect the network by detecting and removing viruses or malwares."; } identity voip-volte-filter { base content-security-control; description "Identity for VoIP/VoLTE security service that filters out the packets or flows of malicious users with a deny list of malicious users in a database"; } identity attack-mitigation-control { base advanced-nsf; Kim, et al. Expires 7 April 2022 [Page 23] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 description "Base identity for attack mitigation control"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model"; } identity anti-ddos { base attack-mitigation-control; description "Identity for advanced NSF Anti-DDoS or DDoS Mitigator capability."; } identity action { description "Base identity for action"; } identity ingress-action { base action; description "Base identity for ingress action"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Ingress Action"; } identity egress-action { base action; description "Base identity for egress action"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Egress Action"; } identity default-action { base action; description "Base identity for default action"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Default Action"; } identity pass { base ingress-action; Kim, et al. Expires 7 April 2022 [Page 24] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 base egress-action; base default-action; description "Identity for pass"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Actions and Default Action"; } identity drop { base ingress-action; base egress-action; base default-action; description "Identity for drop"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Actions and Default Action"; } identity mirror { base ingress-action; base egress-action; base default-action; description "Identity for mirror"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Actions and Default Action"; } identity rate-limit { base ingress-action; base egress-action; base default-action; description "Identity for rate limiting action"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Actions and Default Action"; } identity log-action { base action; Kim, et al. Expires 7 April 2022 [Page 25] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 description "Base identity for log action"; } identity rule-log { base log-action; description "Identity for rule log"; } identity session-log { base log-action; description "Identity for session log"; } identity invoke-signaling { base egress-action; description "Identity for invoke signaling"; } identity tunnel-encapsulation { base egress-action; description "Identity for tunnel encapsulation"; } identity forwarding { base egress-action; description "Identity for forwarding"; } identity transformation { base egress-action; description "Identity for transformation"; } identity redirection { base egress-action; description "Identity for redirection"; } identity resolution-strategy { description Kim, et al. Expires 7 April 2022 [Page 26] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 "Base identity for resolution strategy"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Resolution Strategy"; } identity fmr { base resolution-strategy; description "Identity for First Matching Rule (FMR)"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Resolution Strategy"; } identity lmr { base resolution-strategy; description "Identity for Last Matching Rule (LMR)"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Resolution Strategy"; } identity pmr { base resolution-strategy; description "Identity for Prioritized Matching Rule (PMR)"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Resolution Strategy"; } identity pmre { base resolution-strategy; description "Identity for Prioritized Matching Rule with Errors (PMRE)"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Resolution Strategy"; } identity pmrn { base resolution-strategy; description "Identity for Prioritized Matching Rule with No Errors (PMRN)"; Kim, et al. Expires 7 April 2022 [Page 27] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Resolution Strategy"; } identity day { description "This represents the base for days."; } identity monday { base day; description "This represents Monday."; } identity tuesday { base day; description "This represents Tuesday."; } identity wednesday { base day; description "This represents Wednesday."; } identity thursday { base day; description "This represents Thursday."; } identity friday { base day; description "This represents Friday."; } identity saturday { base day; description "This represents Saturday."; } identity sunday { base day; Kim, et al. Expires 7 April 2022 [Page 28] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 description "This represents Sunday."; } /* * Typedefs */ typedef time { type string { pattern '(0[0-9]|1[0-9]|2[0-3]):[0-5][0-9]:[0-5][0-9](\.\d+)?' + '(Z|[\+\-]((1[0-3]|0[0-9]):([0-5][0-9])|14:00))?'; } description "The time type represents an instance of time of zero-duration that recurs every day."; } /* * Groupings */ grouping ipv4-prefix { description "The list of IPv4 addresses."; leaf ipv4 { type inet:ipv4-address-no-zone; description "The value of IPv4 address."; } choice subnet { description "The subnet can be specified as a prefix length or netmask."; leaf prefix-length { type uint8 { range "0..32"; } description "The length of the subnet prefix."; } leaf netmask { type yang:dotted-quad; description "The subnet specified as a netmask."; } } reference Kim, et al. Expires 7 April 2022 [Page 29] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 "RFC 791: Internet Protocol - IPv4 address RFC 8344: A YANG Data Model for IP Management"; } grouping ipv6-prefix { description "The list of IPv6 addresses."; leaf ipv6 { type inet:ipv6-address-no-zone; description "The value of IPv6 address."; } leaf prefix-length { type uint8 { range "0..128"; } description "The length of the subnet prefix."; } reference "RFC 8200: Internet Protocol, Version 6 (IPv6) Specification - IPv6 address RFC 8344: A YANG Data Model for IP Management"; } grouping ipv4-range { description "Range match for the IPv4 addresses. If only one value is needed, then set both start and end to the same value. The end IPv4 address MUST be equal or greater than the start IPv4 address."; leaf start { type inet:ipv4-address-no-zone; description "Starting IPv4 address for a range match."; } leaf end { type inet:ipv4-address-no-zone; description "Ending IPv4 address for a range match."; } reference "RFC 791: Internet Protocol - IPv4 address"; } grouping ipv6-range { description "Range match for the IPv6 addresses. If only one value is Kim, et al. Expires 7 April 2022 [Page 30] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 needed, then set both start and end to the same value. The end IPv6 address number MUST be equal to or greater than the start IPv6 address."; leaf start { type inet:ipv6-address-no-zone; description "Starting IPv6 address for a range match."; } leaf end { type inet:ipv6-address-no-zone; description "Ending IPv6 address for a range match."; } reference "RFC 8200: Internet Protocol, Version 6 (IPv6) Specification - IPv6 address"; } grouping ipv4-address { description "Grouping for IPv4 address. IPv4 address can be in the form of prefix or range."; choice match-type { description "Choose between Prefix or Range"; case prefix { list ipv4-prefix { key "ipv4"; uses ipv4-prefix; description "The list of IPv4 addresses specified with an IPv4 address and a prefix-length or a netmask."; } } case range { list ipv4-range { key "start end"; uses ipv4-range; description "The list of IPv4 address specified with a start IPv4 address and an end IPv4 address. If only one value is needed, then set both start and end to the same value."; } } } Kim, et al. Expires 7 April 2022 [Page 31] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 } grouping ipv6-address { description "Grouping for IPv6 address. IPv6 address can be in the form of prefix or range."; choice match-type { description "Choose between Prefix or Range"; case prefix { list ipv6-prefix { key "ipv6"; uses ipv6-prefix; description "The list of IPv6 addresses specified with an IPv6 address and a prefix-length."; } } case range { list ipv6-range { key "start end"; uses ipv6-range; description "The list of IPv6 address specified with a start IPv6 address and an end IPv6 address. If only one value is needed, then set both start and end to the same value."; } } } } grouping port-range { leaf start { type inet:port-number; description "Starting port number for a range match."; } leaf end { type inet:port-number; must '. >= ../start' { error-message "The end port number MUST be equal to or greater than the start port number."; } description "Ending port number for a range match."; } Kim, et al. Expires 7 April 2022 [Page 32] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 description "Range match for the port numbers. If only one value is needed, then set both start and end to the same value."; reference "draft-ietf-tcpm-rfc793bis-25: Transmission Control Protocol (TCP) Specification - Port Number RFC 768: User Datagram Protocol - Port Number RFC 4960: Stream Control Transmission Protocol - Port Number RFC 4340: Datagram Congestion Control Protocol (DCCP) - Port Number"; } /* * Data nodes */ list i2nsf-security-policy { key "system-policy-name"; description "Container for security policy including a set of security rules according to certain logic, i.e., their similarity or mutual relations, etc. The network security policy can be applied to both the unidirectional and bidirectional traffic across the NSF. The I2NSF security policies use the Event-Condition-Action (ECA) policy model "; reference "RFC 8329: Framework for Interface to Network Security Functions - I2NSF Flow Security Policy Structure draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Design Principles and ECA Policy Model Overview"; leaf system-policy-name { type string; description "The name of the policy. This must be unique."; } leaf priority-usage { type identityref { base priority-usage; } default priority-by-order; Kim, et al. Expires 7 April 2022 [Page 33] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 description "Priority usage type for security policy rule: priority by order and priority by number"; } leaf resolution-strategy { type identityref { base resolution-strategy; } default fmr; description "The resolution strategies that can be used to specify how to resolve conflicts that occur between actions of the same or different policy rules that are matched and contained in this particular NSF"; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Resolution strategy"; } leaf default-action { type identityref { base default-action; } default mirror; description "This default action can be used to specify a predefined action when no other alternative action was matched by the currently executing I2NSF Policy Rule. An analogy is the use of a default statement in a C switch statement."; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Default Action"; } list rules { key "rule-name"; description "This is a rule for network security functions."; leaf rule-name { type string; description "The name of the rule."; } leaf rule-description { Kim, et al. Expires 7 April 2022 [Page 34] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 type string; description "This description gives more information about rules."; } leaf rule-priority { type uint8 { range "1..255"; } description "The priority keyword comes with a mandatory numeric value which can range from 1 up to 255. Note that a higher number means a higher priority"; } leaf rule-enable { type boolean; description "True is enable. False is not enable."; } leaf session-aging-time { type uint16; units "second"; description "This is session aging time."; } container long-connection { description "A container for long connection. A long connection is a connection that is maintained after the socket connection is established, regardless of whether it is used for data traffic or not."; leaf enable { type boolean; description "True is enabled. False is not enabled."; } leaf duration { type uint16; units "second"; description Kim, et al. Expires 7 April 2022 [Page 35] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 "This is the duration of the long-connection."; } } container event { description "An event is defined as any important occurrence in time of a change in the system being managed, and/or in the environment of the system being managed. When used in the context of policy rules for a flow-based NSF, it is used to determine whether the Condition clause of the Policy Rule can be evaluated or not. Examples of an I2NSF event include time and user actions (e.g., logon, logoff, and actions that violate any ACL.)."; reference "RFC 8329: Framework for Interface to Network Security Functions - I2NSF Flow Security Policy Structure draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Design Principles and ECA Policy Model Overview draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF Monitoring YANG Data Model - Alarms, Events, Logs, and Counters"; leaf event-clause-description { type string; description "Description for an event clause"; } container time { description "Time to determine when the policy should be applied"; leaf start-date-time { type yang:date-and-time; description "This is the start date and time for a security policy rule."; } leaf end-date-time { type yang:date-and-time; description "This is the end date and time for a policy rule. The policy rule will stop working after the specified end-date-time."; Kim, et al. Expires 7 April 2022 [Page 36] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 } container period { when "../frequency!='only-once'"; description "This represents the repetition time. In the case where the frequency is weekly, the days can be set."; leaf start-time { type time; description "This is a period's start time for an event."; } leaf end-time { type time; description "This is a period's end time for an event."; } leaf-list day { when "../../frequency='weekly'"; type identityref{ base day; } min-elements 1; description "This represents the repeated day of every week (e.g., Monday and Tuesday). More than one day can be specified."; } leaf-list date { when "../../frequency='monthly'"; type int32{ range "1..31"; } min-elements 1; description "This represents the repeated date of every month. More than one date can be specified."; } leaf-list month { when "../../frequency='yearly'"; type string{ pattern '\d{2}-\d{2}'; } min-elements 1; Kim, et al. Expires 7 April 2022 [Page 37] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 description "This represents the repeated date and month of every year. More than one can be specified. A pattern used here is Month and Date (MM-DD)."; } } leaf frequency { type enumeration { enum only-once { description "This represents that the rule is immediately enforcedonly once and not repeated. The policy will continuously be active from the start-time to the end-time."; } enum daily { description "This represents that the rule is enforced on a daily basis. The policy will be repeated daily until the end-date."; } enum weekly { description "This represents that the rule is enforced on a weekly basis. The policy will be repeated weekly until the end-date. The repeated days can be specified."; } enum monthly { description "This represents that the rule is enforced on a monthly basis. The policy will be repeated monthly until the end-date."; } enum yearly { description "This represents that the rule is enforced on a yearly basis. The policy will be repeated yearly until the end-date."; } } default only-once; description "This represents how frequently the rule should be enforced."; } } Kim, et al. Expires 7 April 2022 [Page 38] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 container event-clauses { description "System Event Clause - either a system event or system alarm"; reference "RFC 8329: Framework for Interface to Network Security Functions - I2NSF Flow Security Policy Structure draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Design Principles and ECA Policy Model Overview draft-ietf-i2nsf-nsf-monitoring-data-model-09: I2NSF NSF Monitoring YANG Data Model - Alarms, Events, Logs, and Counters"; leaf-list system-event { type identityref { base system-event; } description "The security policy rule according to system events."; } leaf-list system-alarm { type identityref { base system-alarm; } description "The security policy rule according to system alarms."; } } } container condition { description "A condition is defined as a set of attributes, features, and/or values that are to be compared with a set of known attributes, features, and/or values in order to determine whether or not the set of Actions in that (imperative) I2NSF Policy Rule can be executed or not. Examples of I2NSF Conditions include matching attributes of a packet or flow, and comparing the internal state of an NSF to a desired state."; reference "RFC 8329: Framework for Interface to Network Security Functions - I2NSF Flow Security Policy Structure Kim, et al. Expires 7 April 2022 [Page 39] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Design Principles and ECA Policy Model Overview"; leaf condition-clause-description { type string; description "Description for a condition clause."; } container ethernet { description "The purpose of this container is to represent layer 2 packet header information to determine the set of policy actions in this ECA policy rule should be executed or not."; reference "IEEE 802.3: IEEE Standard for Ethernet"; leaf ethernet-description { type string; description "The MAC Condition description"; } leaf-list source-address { type yang:mac-address; description "The condition for source Media Access Control (MAC) Address of a Layer 2 packet. Multiple source MAC Addresses can be given in a single rule."; reference "IEEE 802.3: IEEE Standard for Ethernet"; } leaf-list destination-address { type yang:mac-address; description "The condition for destination Media Access Control (MAC) Address of a Layer 2 packet. Multiple destination MAC Addresses can be given in a single rule."; reference "IEEE 802.3: IEEE Standard for Ethernet"; } leaf-list ether-type { type uint16; Kim, et al. Expires 7 April 2022 [Page 40] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 description "The condition for matching the 2-octet of IEEE 802.3 Length/Type field. Can be specified with decimal or hexadecimal from 0 through 65535 (0xFFFF) A value from 0 through 1500 (0x05DC) specifies the number of MAC client data octets contained in the subsequent MAC Client Data Field of the basic frame A value greater than or equal to 1536 (0x0600) specifies that the Length/Type field indicates Ethertype of the MAC client protocol"; reference "IEEE 802.3: IEEE Standard for Ethernet"; } } container ipv4 { description "The purpose of this container is to represent IPv4 packet header information to determine if the set of policy actions in this ECA policy rule should be executed or not."; reference "RFC 791: Internet Protocol"; leaf description { type string; description "ipv4 condition textual description."; } list header-length { key "start end"; leaf start{ type uint8 { range "5..15"; } description "Starting IPv4 header length for a range match."; } leaf end { type uint8 { range "5..15"; } must '. >= ../start' { error-message Kim, et al. Expires 7 April 2022 [Page 41] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 "The end header length MUST be equal to or greater than the start header length."; } description "Ending IPv4 header length for a range match."; } description "The security policy rule according to IPv4 header length. If only one value is needed, then set both start and end to the same value."; reference "RFC 791: Internet Protocol - Header length"; } leaf-list dscp { type inet:dscp; description "The security policy rule according to IPv4 type of service for DSCP."; reference "RFC 791: Internet Protocol - Type of service RFC 2474: Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers."; } list total-length { key "start end"; leaf start { type uint16; description "Starting IPv4 total length for a range match."; } leaf end { type uint16; must '. >= ../start' { error-message "The end total length MUST be equal to or greater than the start total length."; } description "Ending IPv4 total length for a range match."; } description "The security policy rule according to IPv4 total length. If only one value is needed, then set both start and end to the same value."; reference Kim, et al. Expires 7 April 2022 [Page 42] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 "RFC 791: Internet Protocol - Total length"; } leaf-list identification { type uint16; description "The security policy rule according to IPv4 identification."; reference "RFC 791: Internet Protocol - Identification"; } leaf-list fragment-flags { type identityref { base fragmentation-flags; } description "The security policy rule according to IPv4 fragment flags."; reference "RFC 791: Internet Protocol - Fragment flags"; } list fragment-offset { key "start end"; leaf start { type uint16 { range "0..16383"; } description "Starting IPv4 fragment offset for a range match."; } leaf end { type uint16 { range "0..16383"; } must '. >= ../start' { error-message "The end fragment offset MUST be equal or greater than the start fragment offset."; } description "Ending IPv4 fragment offset for a range match."; } description "The security policy rule according to IPv4 fragment offset."; reference Kim, et al. Expires 7 April 2022 [Page 43] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 "RFC 791: Internet Protocol - Fragment offset"; } list ttl { key "start end"; leaf start { type uint8; description "Starting IPv4 TTL for a range match."; } leaf end { type uint8; must '. >= ../start' { error-message "The end TTL MUST be equal or greater than the start TTL."; } description "Ending IPv4 TTL for a range match."; } description "The security policy rule according to IPv4 time-to-live (TTL). If only one value is needed, then set both start and end to the same value."; reference "RFC 791: Internet Protocol - Time to live"; } leaf-list protocol { type uint8; description "The security policy rule according to IPv4 protocol header field."; reference "RFC 791: Internet Protocol - Protocol IANA: Assigned Internet Protocol Numbers"; } container source-address { uses ipv4-address; description "The security policy rule according to IPv4 source address."; reference "RFC 791: Internet Protocol - IPv4 Address"; } container destination-address { Kim, et al. Expires 7 April 2022 [Page 44] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 uses ipv4-address; description "The security policy rule according to IPv4 destination address."; reference "RFC 791: Internet Protocol - IPv4 Address"; } leaf-list ipopts { type identityref { base ipopts; } description "The security policy rule according to IPv4 options."; reference "RFC 791: Internet Protocol - Options"; } } container ipv6 { description "The purpose of this container is to represent IPv6 packet header information to determine if the set of policy actions in this ECA policy rule should be executed or not."; reference "RFC 8200: Internet Protocol, Version 6 (IPv6) Specification"; leaf description { type string; description "This is description for ipv6 condition."; } leaf-list dscp { type inet:dscp; description "The security policy rule according to IPv6 traffic class for DSCP."; reference "RFC 8200: Internet Protocol, Version 6 (IPv6) Specification - Traffic class RFC 2474: Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers."; Kim, et al. Expires 7 April 2022 [Page 45] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 } list flow-label { key "start end"; leaf start { type inet:ipv6-flow-label; description "Starting IPv6 flow label for a range match."; } leaf end { type inet:ipv6-flow-label; must '. >= ../start' { error-message "The end flow label MUST be equal or greater than the start flow label."; } description "Ending IPv6 flow label for a range match."; } description "The security policy rule according to IPv6 flow label. If only one value is needed, then set both start and end to the same value."; reference "RFC 8200: Internet Protocol, Version 6 (IPv6) Specification - Flow label"; } list payload-length { key "start end"; leaf start { type uint16; description "Starting IPv6 payload length for a range match."; } leaf end { type uint16; must '. >= ../start' { error-message "The end payload length MUST be equal or greater than the start payload length."; } description "Ending IPv6 payload length for a range match."; } description "The security policy rule according to IPv6 payload length. If only one value is needed, Kim, et al. Expires 7 April 2022 [Page 46] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 then set both start and end to the same value."; reference "RFC 8200: Internet Protocol, Version 6 (IPv6) Specification - Payload length"; } leaf-list next-header { type uint8; description "The security policy rule according to IPv6 next header."; reference "RFC 8200: Internet Protocol, Version 6 (IPv6) Specification - Next header IANA: Assigned Internet Protocol Numbers"; } list hop-limit { key "start end"; leaf start { type uint8; description "Start IPv6 hop limit for a range match."; } leaf end { type uint8; must '. >= ../start' { error-message "The end hop limit MUST be equal or greater than the start hop limit."; } description "End IPv6 hop limit for a range match."; } description "The security policy rule according to IPv6 hop limit. If only one value is needed, then set both start and end to the same value."; reference "RFC 8200: Internet Protocol, Version 6 (IPv6) Specification - Hop limit"; } container source-address { uses ipv6-address; description "The security policy rule according to IPv6 source address."; Kim, et al. Expires 7 April 2022 [Page 47] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 reference "RFC 8200: Internet Protocol, Version 6 (IPv6) Specification - IPv6 address"; } container destination-address { uses ipv6-address; description "The security policy rule according to IPv6 destination address."; reference "RFC 8200: Internet Protocol, Version 6 (IPv6) Specification - IPv6 address"; } } container tcp { description "The purpose of this container is to represent TCP packet header information to determine if the set of policy actions in this ECA policy rule should be executed or not."; reference "draft-ietf-tcpm-rfc793bis-25: Transmission Control Protocol (TCP) Specification"; leaf description { type string; description "This is description for tcp condition."; } list source-port-number { key "start end"; uses port-range; description "The security policy rule according to tcp source port number."; reference "draft-ietf-tcpm-rfc793bis-25: Transmission Control Protocol (TCP) Specification - Port Number"; } list destination-port-number { key "start end"; uses port-range; description Kim, et al. Expires 7 April 2022 [Page 48] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 "The security policy rule according to tcp destination port number."; reference "draft-ietf-tcpm-rfc793bis-25: Transmission Control Protocol (TCP) Specification - Port Number"; } leaf-list flags { type identityref { base tcp-flags; } description "The security policy rule according to tcp flags."; reference "draft-ietf-tcpm-rfc793bis-25: Transmission Control Protocol (TCP) Specification - Flags"; } } container udp { description "The purpose of this container is to represent UDP packet header information to determine if the set of policy actions in this ECA policy rule should be executed or not."; reference "RFC 768: User Datagram Protocol"; leaf description { type string; description "This is description for udp condition."; } container source-port-number { uses port-range; description "The security policy rule according to udp source port number."; reference "RFC 768: User Datagram Protocol - Port Number"; } container destination-port-number { uses port-range; description "The security policy rule according to Kim, et al. Expires 7 April 2022 [Page 49] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 udp destination port number."; reference "RFC 768: User Datagram Protocol - Port Number"; } list total-length { key "start end"; leaf start { type uint32; description "Start udp total length for a range match."; } leaf end { type uint32; must '. >= ../start' { error-message "The end hop limit MUST be equal or greater than the start hop limit."; } description "End udp total length for a range match."; } description "The security policy rule according to udp total length. If only one value is needed, then set both start and end to the same value"; reference "RFC 768: User Datagram Protocol - Total Length"; } } container sctp { description "The purpose of this container is to represent SCTP packet header information to determine if the set of policy actions in this ECA policy rule should be executed or not."; leaf description { type string; description "This is description for sctp condition."; } container source-port-number { uses port-range; description "The security policy rule according to sctp source port number."; Kim, et al. Expires 7 April 2022 [Page 50] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 reference "RFC 4960: Stream Control Transmission Protocol - Port number"; } container destination-port-number { uses port-range; description "The security policy rule according to sctp destination port number."; reference "RFC 4960: Stream Control Transmission Protocol - Port Number"; } leaf-list verification-tag { type uint32; description "The security policy rule according to udp total length."; reference "RFC 4960: Stream Control Transmission Protocol - Verification Tag"; } leaf-list chunk-type { type uint8; description "The security policy rule according to sctp chunk type ID Value."; reference "RFC 4960: Stream Control Transmission Protocol - Chunk Type"; } } container dccp { description "The purpose of this container is to represent DCCP packet header information to determine if the set of policy actions in this ECA policy rule should be executed or not."; leaf description { type string; description "This is description for dccp condition."; } Kim, et al. Expires 7 April 2022 [Page 51] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 container source-port-number { uses port-range; description "The security policy rule according to dccp source port number."; reference "RFC 4340: Datagram Congestion Control Protocol (DCCP) - Port number"; } container destination-port-number { uses port-range; description "The security policy rule according to dccp destination port number."; reference "RFC 4340: Datagram Congestion Control Protocol (DCCP) - Port number"; } leaf-list service-code { type uint32; description "The security policy rule according to dccp service code."; reference "RFC 4340: Datagram Congestion Control Protocol (DCCP) - Service Codes RFC 5595: The Datagram Congestion Control Protocol (DCCP) Service Codes RFC 6335: Internet Assigned Numbers Authority (IANA) Procedures for the Management of the Service Name and Transport Protocol Port Number Registry - Service Code"; } } list icmp { key "version"; description "The purpose of this container is to represent ICMP packet header information to determine if the set of policy actions in this ECA policy rule should be executed or not."; reference "RFC 792: Internet Control Message Protocol RFC 8335: PROBE: A Utility for Probing Interfaces"; Kim, et al. Expires 7 April 2022 [Page 52] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 leaf description { type string; description "This is description for icmp condition."; } leaf version { type enumeration { enum icmpv4 { value "1"; description "The ICMPv4 Protocol as defined in RFC 792"; } enum icmpv6 { value "2"; description "The ICMPv6 Protocol as defined in RFC 4443"; } } description "The ICMP version to be matched. This value affected the type and code values."; reference "RFC 792: Internet Control Message Protocol RFC 4443: Internet Control Message Protocol (ICMPv6) for the Internet Protocol Version 6 (IPv6) Specification"; } leaf-list type { type uint8; description "The security policy rule according to ICMPv4 or ICMPv6 type header field. The value of this leaf-list is affected by the value of the leaf version. If the version value is icmpv4, the type follows the IANA ICMP Parameters. If the version value is icmpv6, the type follows the IANA ICMPv6 Parameters."; reference "RFC 792: Internet Control Message Protocol RFC 4443: Internet Control Message Protocol (ICMPv6) for the Internet Protocol Version 6 (IPv6) Specification Kim, et al. Expires 7 April 2022 [Page 53] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 RFC 8335: PROBE: A Utility for Probing Interfaces IANA: Internet Control Message Protocol (ICMP) Parameters IANA: Internet Control Message Protocol version 6 (ICMPv6) Parameters"; } leaf-list code { type uint8; description "The security policy rule according to ICMPv4 or ICMPv6 code header field. The value of this leaf-list is affected by the value of the leaf version. If the version value is icmpv4, the code follows the IANA ICMP parameters. If the version value is icmpv6, the code follows the IANA ICMPv6 parameters."; reference "RFC 792: Internet Control Message Protocol RFC 4443: Internet Control Message Protocol (ICMPv6) for the Internet Protocol Version 6 (IPv6) Specification RFC 8335: PROBE: A Utility for Probing Interfaces IANA: Internet Control Message Protocol (ICMP) Parameters IANA: Internet Control Message Protocol version 6 (ICMPv6) Parameters"; } } container url-category { description "Condition for url category"; leaf description { type string; description "This is description for the condition of a URL's category such as SNS sites, game sites, ecommerce sites, company sites, and university sites."; } leaf-list pre-defined-category { type string; description Kim, et al. Expires 7 April 2022 [Page 54] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 "This is pre-defined-category."; } leaf-list user-defined-category { type string; description "This user-defined-category."; } } container voice { description "For the VoIP/VoLTE security system, a VoIP/ VoLTE security system can monitor each VoIP/VoLTE flow and manage VoIP/VoLTE security rules controlled by a centralized server for VoIP/VoLTE security service (called VoIP IPS). The VoIP/VoLTE security system controls each switch for the VoIP/VoLTE call flow management by manipulating the rules that can be added, deleted, or modified dynamically."; reference "RFC 3261: SIP: Session Initiation Protocol"; leaf description { type string; description "This is description for voice condition."; } leaf-list source-voice-id { type string; description "The security policy rule according to a source voice ID for VoIP and VoLTE."; } leaf-list destination-voice-id { type string; description "The security policy rule according to a destination voice ID for VoIP and VoLTE."; } leaf-list user-agent { type string; description "The security policy rule according to Kim, et al. Expires 7 April 2022 [Page 55] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 an user agent for VoIP and VoLTE."; } } container ddos { description "Condition for DDoS attack."; leaf description { type string; description "This is description for ddos condition."; } leaf alert-packet-rate { type uint32; units "pps"; description "The alert rate of flood detection for packets per second (PPS) of an IP address."; } leaf alert-flow-rate { type uint32; description "The alert rate of flood detection for flows per second of an IP address."; } leaf alert-byte-rate { type uint32; units "BPS"; description "The alert rate of flood detection for bytes per second of an IP address."; } } container anti-virus { description "Condition for antivirus"; leaf-list profile { type string; description "The security profile for antivirus. This is used to update the security profile for improving the security. The security profile is used to scan Kim, et al. Expires 7 April 2022 [Page 56] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 the viruses."; } leaf-list exception-files { type string; description "The type or name of the files to be excluded by the anti-virus. This can be used to keep the known harmless files."; } } container payload { description "Condition for packet payload"; leaf packet-payload-description { type string; description "This is description for payload condition."; } leaf-list payload-content { type string; description "This is a condition for packet payload content."; } } container context { description "Condition for context"; leaf context-description { type string; description "This is description for context condition."; } container application { description "Condition for application"; leaf description { type string; description "This is description for application condition."; } leaf-list object { type string; description "This is application object."; Kim, et al. Expires 7 April 2022 [Page 57] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 } leaf-list group { type string; description "This is application group."; } leaf-list label { type string; description "This is application label."; } container category { description "This is application category"; list application-category { key "name subcategory"; description "This is application category list"; leaf name { type string; description "This is name for application category."; } leaf subcategory { type string; description "This is application subcategory."; } } } } container target { description "Condition for target"; leaf description { type string; description "This is description for target condition. Vendors can write instructions for target condition that vendor made"; } leaf-list device { type identityref { base target-device; } Kim, et al. Expires 7 April 2022 [Page 58] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 description "The device attribute that can identify a device, including the device type (i.e., router, switch, pc, ios, or android) and the device's owner as well."; } } container users { description "Condition for users"; leaf users-description { type string; description "This is the description for users' condition."; } list user { key "user-id"; description "The user with which the traffic flow is associated can be identified by either a user id or user name. The user-to-IP address mapping is assumed to be provided by the unified user management system via network."; leaf user-id { type uint32; description "The ID of the user."; } leaf user-name { type string; description "The name of the user."; } } list group { key "group-id"; description "The user group with which the traffic flow is associated can be identified by either a group id or group name. The group-to-IP address and user-to-group mappings are assumed to be provided by the unified user management system via network."; leaf group-id { type uint32; description "The ID of the group."; } Kim, et al. Expires 7 April 2022 [Page 59] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 leaf group-name { type string; description "The name of the group."; } } leaf security-group { type string; description "security-group."; } } container geography-location { description "The location which network traffic flow is associated with. The region can be the geographical location such as country, province, and city, as well as the logical network location such as IP address, network section, and network domain."; leaf description { type string; description "This is description for generic context condition. Vendors can write instructions for generic context condition that vendor made"; } leaf-list source { type string; description "The src-geography-location is a geographical location mapped into an IP address. It matches the mapped IP address to the source IP address of the traffic flow."; reference "ISO 3166: Codes for the representation of names of countries and their subdivisions"; } leaf-list destination { type string; description "The dest-geography-location is a geographical location mapped into an IP address. It matches the mapped IP address to the destination IP address of Kim, et al. Expires 7 April 2022 [Page 60] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 the traffic flow."; reference "ISO 3166: Codes for the representation of names of countries and their subdivisions"; } } } } container action { description "An action is used to control and monitor aspects of flow-based NSFs when the event and condition clauses are satisfied. NSFs provide security functions by executing various Actions. Examples of I2NSF Actions include providing intrusion detection and/or protection, web and flow filtering, and deep packet inspection for packets and flows."; reference "RFC 8329: Framework for Interface to Network Security Functions - I2NSF Flow Security Policy Structure draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Design Principles and ECA Policy Model Overview"; leaf action-clause-description { type string; description "Description for an action clause."; } container packet-action { description "Action for packets"; reference "RFC 8329: Framework for Interface to Network Security Functions - I2NSF Flow Security Policy Structure draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Design Principles and ECA Policy Model Overview"; leaf ingress-action { type identityref { base ingress-action; } description "Ingress Action: pass, drop, rate-limit, and mirror."; Kim, et al. Expires 7 April 2022 [Page 61] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 } leaf egress-action { type identityref { base egress-action; } description "Egress action: pass, drop, rate-limit, mirror, invoke-signaling, tunnel-encapsulation, forwarding, and redirection."; } leaf log-action { type identityref { base log-action; } description "Log action: rule log and session log"; } } container flow-action { description "Action for flows"; reference "RFC 8329: Framework for Interface to Network Security Functions - I2NSF Flow Security Policy Structure draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - Design Principles and ECA Policy Model Overview"; leaf ingress-action { type identityref { base ingress-action; } description "Action: pass, drop, rate-limit, and mirror."; } leaf egress-action { type identityref { base egress-action; } description "Egress action: pass, drop, rate-limit, mirror, invoke-signaling, tunnel-encapsulation, forwarding, and redirection."; Kim, et al. Expires 7 April 2022 [Page 62] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 } leaf log-action { type identityref { base log-action; } description "Log action: rule log and session log"; } } container advanced-action { description "If the packet needs to be additionally inspected, the packet is passed to advanced network security functions according to the profile. The profile means the types of NSFs where the packet will be forwarded in order to additionally inspect the packet. The advanced action activates Service Function Chaining (SFC) for further inspection of a packet."; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - YANG Tree Diagram"; leaf-list content-security-control { type identityref { base content-security-control; } description "Content-security-control is the NSFs that inspect the payload of the packet. The profile for the types of NSFs for mitigation is divided into content security control and attack-mitigation-control. Content security control: ips, url filtering, anti-virus, and voip-volte-filter. This can be extended according to the provided NSFs."; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - YANG Tree Diagram"; } leaf-list attack-mitigation-control { type identityref { base attack-mitigation-control; } Kim, et al. Expires 7 April 2022 [Page 63] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 description "Attack-mitigation-control is the NSFs that weaken the attacks related to a denial of service and reconnaissance. The profile for the types of NSFs for mitigation is divided into content security control and attack-mitigation-control. Attack mitigation control: Anti-DDoS or DDoS mitigator. This can be extended according to the provided NSFs such as mitigators for ip sweep, port scanning, ping of death, teardrop, oversized icmp, and tracert."; reference "draft-ietf-i2nsf-capability-data-model-17: I2NSF Capability YANG Data Model - YANG Tree Diagram"; } } } } container rule-group { description "This is rule group"; list groups { key "group-name"; description "This is a group for rules"; leaf group-name { type string; description "This is a group for rules"; } leaf-list rule-name { type leafref { path "../../../rules/rule-name"; } description "The names of the rules to be grouped."; } leaf enable { type boolean; description "True is enabled, and False is not enabled."; } Kim, et al. Expires 7 April 2022 [Page 64] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 leaf description { type string; description "This is a description for rule-group"; } } } } } Figure 5: YANG Data Module of I2NSF NSF-Facing-Interface 5. XML Configuration Examples of Low-Level Security Policy Rules This section shows XML configuration examples of low-level security policy rules that are delivered from the Security Controller to NSFs over the NSF-Facing Interface. For security requirements, we assume that the NSFs (i.e., General firewall, Time-based firewall, URL filter, VoIP/VoLTE filter, and http and https flood mitigation ) described in of [I-D.ietf-i2nsf-capability-data-model] are registered in the I2NSF framework. With the registered NSFs, we show configuration examples for security policy rules of network security functions according to the following three security requirements: (i) Block Social Networking Service (SNS) access during business hours, (ii) Block malicious VoIP/VoLTE packets coming to the company, and (iii) Mitigate http and https flood attacks on company web server. 5.1. Security Requirement 1: Block Social Networking Service (SNS) Access during Business Hours This section shows a configuration example for blocking SNS access during business hours in IPv4 networks or IPv6 networks. Kim, et al. Expires 7 April 2022 [Page 65] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 sns_access block_sns_access_during_operation_time weekly 192.0.2.11 192.0.2.90 url-filtering Figure 6: Configuration XML for Time-based Firewall to Block SNS Access during Business Hours in IPv4 Networks Kim, et al. Expires 7 April 2022 [Page 66] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 sns_access block_sns_access_during_operation_time weekly 2001:DB8:0:1::11 2001:DB8:0:1::90 url-filtering Figure 7: Configuration XML for Time-based Firewall to Block SNS Access during Business Hours in IPv6 Networks Kim, et al. Expires 7 April 2022 [Page 67] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 sns_access block_sns_access_during_operation_time SNS_1 SNS_2 drop Figure 8: Configuration XML for Web Filter to Block SNS Access during Business Hours Figure 6 (or Figure 7) and Figure 8 show the configuration XML documents for time-based firewall and web filter to block SNS access during business hours in IPv4 networks (or IPv6 networks). For the security requirement, two NSFs (i.e., a time-based firewall and a web filter) were used because one NSF cannot meet the security requirement. The instances of XML documents for the time-based firewall and the web filter are as follows: Note that a detailed data model for the configuration of the advanced network security function (i.e., web filter) can be defined as an extension in future. Time-based Firewall is as follows: 1. The name of the system policy is sns_access. 2. The name of the rule is block_sns_access_during_operation_time. 3. The rule is started from 2021-03-11 at 9 a.m. to 2021-12-31 at 6 p.m. 4. The rule is operated weekly every weekday (i.e., Monday, Tuesday, Wednesday, Thursday, and Friday) during the business hours (i.e., from 9 a.m. to 6 p.m.) . Kim, et al. Expires 7 April 2022 [Page 68] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 5. The rule inspects a source IPv4 address (i.e., from 192.0.2.11 to 192.0.2.90) to inspect the outgoing packets of employees. For the case of IPv6 networks, the rule inspects a source IPv6 address (i.e., from 2001:DB8:0:1::11 to 2001:DB8:0:1::90) to inspect the outgoing packets of employees. 6. If the outgoing packets match the rules above, the time-based firewall sends the packets to url filtering for additional inspection because the time-based firewall can not inspect contents of the packets for the SNS URL. Web Filter is as follows: 1. The name of the system policy is sns_access. 2. The name of the rule is block_SNS_1_and_SNS_2. 3. The rule inspects URL address to block the access packets to the SNS_1 or the SNS_2. 4. If the outgoing packets match the rules above, the packets are blocked. 5.2. Security Requirement 2: Block Malicious VoIP/VoLTE Packets Coming to a Company This section shows a configuration example for blocking malicious VoIP/VoLTE packets coming to a company. Kim, et al. Expires 7 April 2022 [Page 69] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 voip_volte_inspection block_malicious_voice_id 192.0.2.11 192.0.2.90 5060 5061 voip-volte-filter Figure 9: Configuration XML for General Firewall to Block Malicious VoIP/VoLTE Packets Coming to a Company Kim, et al. Expires 7 April 2022 [Page 70] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 voip_volte_inspection block_malicious_voice_id user1@voip.malicious.example.com user2@voip.malicious.example.com drop Figure 10: Configuration XML for VoIP/VoLTE Filter to Block Malicious VoIP/VoLTE Packets Coming to a Company Figure 9 and Figure 10 show the configuration XML documents for general firewall and VoIP/VoLTE filter to block malicious VoIP/VoLTE packets coming to a company. For the security requirement, two NSFs (i.e., a general firewall and a VoIP/VoLTE filter) were used because one NSF can not meet the security requirement. The instances of XML documents for the general firewall and the VoIP/VoLTE filter are as follows: Note that a detailed data model for the configuration of the advanced network security function (i.e., VoIP/VoLTE filter) can be described as an extension in future. General Firewall is as follows: 1. The name of the system policy is voip_volte_inspection. 2. The name of the rule is block_malicious_voip_volte_packets. 3. The rule inspects a destination IPv4 address (i.e., from 192.0.2.11 to 192.0.2.90) to inspect the packets coming into the company. 4. The rule inspects a port number (i.e., 5060 and 5061) to inspect VoIP/VoLTE packet. Kim, et al. Expires 7 April 2022 [Page 71] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 5. If the incoming packets match the rules above, the general firewall sends the packets to VoIP/VoLTE filter for additional inspection because the general firewall can not inspect contents of the VoIP/VoLTE packets. VoIP/VoLTE Filter is as follows: 1. The name of the system policy is malicious_voice_id. 2. The name of the rule is block_malicious_voice_id. 3. The rule inspects the voice id of the VoIP/VoLTE packets to block the malicious VoIP/VoLTE packets (i.e., user1@voip.malicious.example.com and user2@voip.malicious.example.com). 4. If the incoming packets match the rules above, the packets are blocked. 5.3. Security Requirement 3: Mitigate HTTP and HTTPS Flood Attacks on a Company Web Server This section shows a configuration example for mitigating http and https flood attacks on a company web server. Kim, et al. Expires 7 April 2022 [Page 72] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 flood_attack_mitigation mitigate_http_and_https_flood_attack 192.0.2.11 192.0.2.11 80 80 443 443 anti-ddos Figure 11: Configuration XML for General Firewall to Mitigate HTTP and HTTPS Flood Attacks on a Company Web Server Kim, et al. Expires 7 April 2022 [Page 73] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 flood_attack_mitigation mitigate_http_and_https_flood_attack 1000 drop Figure 12: Configuration XML for Anti-DDoS to Mitigate HTTP and HTTPS Flood Attacks on a Company Web Server Figure 11 and Figure 12 show the configuration XML documents for general firewall and http and https flood attack mitigation to mitigate http and https flood attacks on a company web server. For the security requirement, two NSFs (i.e., a general firewall and a http and https flood attack mitigation) were used because one NSF can not meet the security requirement. The instances of XML documents for the general firewall and http and https flood attack mitigation are as follows: Note that a detailed data model for the configuration of the advanced network security function (i.e., http and https flood attack mitigation) can be defined as an extension in future. General Firewall is as follows: 1. The name of the system policy is flood_attack_mitigation. 2. The name of the rule is mitigate_http_and_https_flood_attack. 3. The rule inspects a destination IPv4 address (i.e., 192.0.2.11) to inspect the access packets coming into the company web server. 4. The rule inspects a port number (i.e., 80 and 443) to inspect http and https packet. 5. If the packets match the rules above, the general firewall sends the packets to anti-DDoS for additional inspection because the general firewall can not control the amount of packets for http and https packets. Kim, et al. Expires 7 April 2022 [Page 74] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 Anti DDoS for HTTP and HTTPS Flood Attack Mitigation is as follows: 1. The name of the system policy is flood_attack_mitigation. 2. The name of the rule is mitigate_http_and_https_flood_attack. 3. The rule controls the http and https packets according to the amount of incoming packets (1000 packets per second). 4. If the incoming packets match the rules above, the packets are blocked. 6. IANA Considerations This document requests IANA to register the following URI in the "IETF XML Registry" [RFC3688]: URI: urn:ietf:params:xml:ns:yang:ietf-i2nsf-policy-rule-for-nsf Registrant Contact: The IESG. XML: N/A; the requested URI is an XML namespace. This document requests IANA to register the following YANG module in the "YANG Module Names" registry [RFC7950][RFC8525]. name: ietf-i2nsf-policy-rule-for-nsf namespace: urn:ietf:params:xml:ns:yang:ietf-i2nsf-policy-rule-for-nsf prefix: nsfintf reference: RFC XXXX 7. Security Considerations The YANG module specified in this document defines a data schema designed to be accessed through network management protocols such as NETCONF [RFC6241] or RESTCONF [RFC8040]. The lowest NETCONF layer is the secure transport layer, and the required secure transport is Secure Shell (SSH) [RFC6242]. The lowest RESTCONF layer is HTTPS, and the required secure transport is TLS [RFC8446]. The NETCONF access control model [RFC8341] provides a means of restricting access to specific NETCONF or RESTCONF users to a preconfigured subset of all available NETCONF or RESTCONF protocol operations and content. There are a number of data nodes defined in this YANG module that are writable/creatable/deletable (i.e., config true, which is the default). These data nodes may be considered sensitive or vulnerable Kim, et al. Expires 7 April 2022 [Page 75] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 in some network environments. Write operations (e.g., edit-config) to these data nodes without proper protection can have a negative effect on network operations. These are the subtrees and data nodes and their sensitivity/vulnerability: * ietf-i2nsf-policy-rule-for-nsf: Writing to almost any element of this YANG module would directly impact on the configuration of NSFs, e.g., completely turning off security monitoring and mitigation capabilities; altering the scope of this monitoring and mitigation; creating an overwhelming logging volume to overwhelm downstream analytics or storage capacity; creating logging patterns which are confusing; or rendering useless trained statistics or artificial intelligence models. Some of the readable data nodes in this YANG module may be considered sensitive or vulnerable in some network environments. It is thus important to control read access (e.g., via get, get-config, or notification) to these data nodes. These are the subtrees and data nodes and their sensitivity/vulnerability: * ietf-i2nsf-policy-rule-for-nsf: The attacker may gather the security policy information of any target NSFs and misuse the security policy information for subsequent attacks. Policy rules identifying the specified users and user groups can be specified with "rules/condition/context/users". As with other data in this YANG module, this user information is provided by the Security Controller to the NSFs and is protected via the transport and access control mechanisms described above. 8. Acknowledgments This work was supported by Institute of Information & Communications Technology Planning & Evaluation (IITP) grant funded by the Korea MSIT (Ministry of Science and ICT) (R-20160222-002755, Cloud based Security Intelligence Technology Development for the Customized Security Service Provisioning). This work was supported in part by the IITP (2020-0-00395, Standard Development of Blockchain based Network Management Automation Technology). 9. Contributors This document is made by the group effort of I2NSF working group. Many people actively contributed to this document, such as Acee Lindem and Roman Danyliw. The authors sincerely appreciate their contributions. The following are co-authors of this document: Kim, et al. Expires 7 April 2022 [Page 76] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 Patrick Lingga Department of Electrical and Computer Engineering Sungkyunkwan University 2066 Seo-ro Jangan-gu Suwon, Gyeonggi-do 16419 Republic of Korea EMail: patricklink@skku.edu Hyoungshick Kim Department of Computer Science and Engineering Sungkyunkwan University 2066 Seo-ro Jangan-gu Suwon, Gyeonggi-do 16419 Republic of Korea EMail: hyoung@skku.edu Daeyoung Hyun Department of Computer Science and Engineering Sungkyunkwan University 2066 Seo-ro Jangan-gu Suwon, Gyeonggi-do 16419 Republic of Korea EMail: dyhyun@skku.edu Dongjin Hong Department of Electronic, Electrical and Computer Engineering Sungkyunkwan University 2066 Seo-ro Jangan-gu Suwon, Gyeonggi-do 16419 Republic of Korea EMail: dong.jin@skku.edu Liang Xia Huawei 101 Software Avenue Nanjing, Jiangsu 210012 China EMail: Frank.Xialiang@huawei.com Tae-Jin Ahn Korea Telecom 70 Yuseong-Ro, Yuseong-Gu Daejeon, 305-811 Republic of Korea EMail: taejin.ahn@kt.com Se-Hui Lee Korea Telecom 70 Yuseong-Ro, Yuseong-Gu Daejeon, 305-811 Republic of Korea EMail: sehuilee@kt.com 10. References 10.1. Normative References [RFC0768] Postel, J., "User Datagram Protocol", STD 6, RFC 768, DOI 10.17487/RFC0768, August 1980, . [RFC0791] Postel, J., "Internet Protocol", STD 5, RFC 791, DOI 10.17487/RFC0791, September 1981, . [RFC0792] Postel, J., "Internet Control Message Protocol", STD 5, RFC 792, DOI 10.17487/RFC0792, September 1981, . [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . Kim, et al. Expires 7 April 2022 [Page 77] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 [RFC2474] Nichols, K., Blake, S., Baker, F., and D. Black, "Definition of the Differentiated Services Field (DS Field) in the IPv4 and IPv6 Headers", RFC 2474, DOI 10.17487/RFC2474, December 1998, . [RFC3261] Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A., Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP: Session Initiation Protocol", RFC 3261, DOI 10.17487/RFC3261, June 2002, . [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, DOI 10.17487/RFC3688, January 2004, . [RFC4340] Kohler, E., Handley, M., and S. Floyd, "Datagram Congestion Control Protocol (DCCP)", RFC 4340, DOI 10.17487/RFC4340, March 2006, . [RFC4443] Conta, A., Deering, S., and M. Gupta, Ed., "Internet Control Message Protocol (ICMPv6) for the Internet Protocol Version 6 (IPv6) Specification", STD 89, RFC 4443, DOI 10.17487/RFC4443, March 2006, . [RFC4960] Stewart, R., Ed., "Stream Control Transmission Protocol", RFC 4960, DOI 10.17487/RFC4960, September 2007, . [RFC5595] Fairhurst, G., "The Datagram Congestion Control Protocol (DCCP) Service Codes", RFC 5595, DOI 10.17487/RFC5595, September 2009, . [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, DOI 10.17487/RFC6020, October 2010, . [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., and A. Bierman, Ed., "Network Configuration Protocol (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011, . [RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011, . Kim, et al. Expires 7 April 2022 [Page 78] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 [RFC6335] Cotton, M., Eggert, L., Touch, J., Westerlund, M., and S. Cheshire, "Internet Assigned Numbers Authority (IANA) Procedures for the Management of the Service Name and Transport Protocol Port Number Registry", BCP 165, RFC 6335, DOI 10.17487/RFC6335, August 2011, . [RFC6991] Schoenwaelder, J., Ed., "Common YANG Data Types", RFC 6991, DOI 10.17487/RFC6991, July 2013, . [RFC7950] Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language", RFC 7950, DOI 10.17487/RFC7950, August 2016, . [RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017, . [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, May 2017, . [RFC8200] Deering, S. and R. Hinden, "Internet Protocol, Version 6 (IPv6) Specification", STD 86, RFC 8200, DOI 10.17487/RFC8200, July 2017, . [RFC8335] Bonica, R., Thomas, R., Linkova, J., Lenart, C., and M. Boucadair, "PROBE: A Utility for Probing Interfaces", RFC 8335, DOI 10.17487/RFC8335, February 2018, . [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, . [RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration Access Control Model", STD 91, RFC 8341, DOI 10.17487/RFC8341, March 2018, . [RFC8344] Bjorklund, M., "A YANG Data Model for IP Management", RFC 8344, DOI 10.17487/RFC8344, March 2018, . Kim, et al. Expires 7 April 2022 [Page 79] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 [RFC8407] Bierman, A., "Guidelines for Authors and Reviewers of Documents Containing YANG Data Models", BCP 216, RFC 8407, DOI 10.17487/RFC8407, October 2018, . [RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018, . [RFC8525] Bierman, A., Bjorklund, M., Schoenwaelder, J., Watsen, K., and R. Wilton, "YANG Library", RFC 8525, DOI 10.17487/RFC8525, March 2019, . [I-D.ietf-tcpm-rfc793bis] Eddy, W. M., "Transmission Control Protocol (TCP) Specification", Work in Progress, Internet-Draft, draft- ietf-tcpm-rfc793bis-25, 7 September 2021, . [I-D.ietf-i2nsf-capability-data-model] Hares, S., Jeong, J. (., Kim, J. (., Moskowitz, R., and Q. Lin, "I2NSF Capability YANG Data Model", Work in Progress, Internet-Draft, draft-ietf-i2nsf-capability-data-model-19, 28 September 2021, . [I-D.ietf-i2nsf-nsf-monitoring-data-model] Jeong, J. (., Lingga, P., Hares, S., Xia, L. (., and H. Birkholz, "I2NSF NSF Monitoring Interface YANG Data Model", Work in Progress, Internet-Draft, draft-ietf- i2nsf-nsf-monitoring-data-model-10, 15 September 2021, . 10.2. Informative References [RFC8329] Lopez, D., Lopez, E., Dunbar, L., Strassner, J., and R. Kumar, "Framework for Interface to Network Security Functions", RFC 8329, DOI 10.17487/RFC8329, February 2018, . Kim, et al. Expires 7 April 2022 [Page 80] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 [I-D.ietf-i2nsf-consumer-facing-interface-dm] Jeong, J. (., Chung, C., Ahn, T., Kumar, R., and S. Hares, "I2NSF Consumer-Facing Interface YANG Data Model", Work in Progress, Internet-Draft, draft-ietf-i2nsf-consumer- facing-interface-dm-15, 15 September 2021, . [ISO-Country-Codes] "Codes for the representation of names of countries and their subdivisions", ISO 3166, September 2018, . [IANA-Protocol-Numbers] Internet Assigned Numbers Authority (IANA), "Assigned Internet Protocol Numbers", September 2020, . [IANA-ICMP-Parameters] Internet Assigned Numbers Authority (IANA), "Internet Control Message Procotol (ICMP) Parameters", February 2021, . [IANA-ICMPv6-Parameters] Internet Assigned Numbers Authority (IANA), "Internet Control Message Procotol version 6 (ICMPv6) Parameters", February 2021, . [IEEE-802.3] Institute of Electrical and Electronics Engineers, "IEEE Standard for Ethernet", 2018, . Authors' Addresses Jinyong (Tim) Kim (editor) Department of Electronic, Electrical and Computer Engineering Sungkyunkwan University 2066 Seobu-Ro, Jangan-Gu Suwon Gyeonggi-Do 16419 Republic of Korea Phone: +82 10 8273 0930 Kim, et al. Expires 7 April 2022 [Page 81] Internet-Draft NSF-Facing Interface YANG Data Model October 2021 Email: timkim@skku.edu Jaehoon (Paul) Jeong (editor) Department of Computer Science and Engineering Sungkyunkwan University 2066 Seobu-Ro, Jangan-Gu Suwon Gyeonggi-Do 16419 Republic of Korea Phone: +82 31 299 4957 Email: pauljeong@skku.edu URI: http://iotlab.skku.edu/people-jaehoon-jeong.php Jung-Soo Park Electronics and Telecommunications Research Institute 218 Gajeong-Ro, Yuseong-Gu Daejeon 34129 Republic of Korea Phone: +82 42 860 6514 Email: pjs@etri.re.kr Susan Hares Huawei 7453 Hickory Hill Saline, MI 48176 United States of America Phone: +1-734-604-0332 Email: shares@ndzh.com Qiushi Lin Huawei Huawei Industrial Base Shenzhen Guangdong 518129, China Email: linqiushi@huawei.com Kim, et al. Expires 7 April 2022 [Page 82]