| Internet-Draft | Consumer-Facing Interface YANG Data Mode | January 2022 |
| Jeong, et al. | Expires 1 August 2022 | [Page] |
This document describes an information model and a YANG data model for the Consumer-Facing Interface between an Interface to Network Security Functions (I2NSF) User and Security Controller in an I2NSF system in a Network Functions Virtualization (NFV) environment. The information model defines various types of managed objects and the relationship among them needed to build the interface. The information model is based on the "Event-Condition-Action" (ECA) policy model defined by a capability information model for I2NSF, and the data model is defined for enabling different users of a given I2NSF system to define, manage, and monitor security policies for specific flows within an administrative domain.¶
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 1 August 2022.¶
Copyright (c) 2022 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 and restrictions with respect to this document. Code Components extracted from this document must include Revised BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Revised BSD License.¶
In a framework of Interface to Network Security Functions (I2NSF) [RFC8329], each vendor can register their NSFs using a Developer's Management System (DMS). Assuming that vendors also provide the front-end web applications registered with an I2NSF User, the Consumer-Facing Interface is required because the web applications developed by each vendor need to have a standard interface specifying the data types used when the I2NSF User and Security Controller communicate using this interface. Therefore, this document specifies the required information, their data types, and encoding schemes so that high-level security policies (or configuration information for security policies) can be transferred to the Security Controller through the Consumer-Facing Interface. These policies can easily be translated by the Security Controller into low-level security policies. The Security Controller delivers the translated policies to Network Security Functions (NSFs) according to their respective security capabilities for the required securiy enforcement.¶
The Consumer-Facing Interface would be built using a set of objects, with each object capturing a unique set of information from Security Administrator (i.e., I2NSF User [RFC8329]) needed to express a Security Policy. An object may have relationship with various other objects to express a complete set of requirements. An information model captures the managed objects and relationship among these objects. The information model proposed in this document is structured in accordance with the "Event-Condition-Action" (ECA) policy model.¶
An NSF Capability model is proposed in [I-D.ietf-i2nsf-capability] as the basic model for both the NSF-Facing interface and Consumer-Facing Interface security policy model of this document.¶
[RFC3444] explains differences between an information and data model. This document uses the guidelines in [RFC3444] to define both the information and data model for Consumer-Facing Interface. Figure 1 shows a high-level abstraction of Consumer-Facing Interface. A data model, which represents an implementation of the information model in a specific data representation language, is also defined in this document.¶
+-----------------+
| Consumer-Facing |
| Interface |
+--------+--------+
^
|
+-------------+------------+
| | |
+-----+----+ +-----+----+ +----+---+
| Policy | | Endpoint | | Threat |
| | | groups | | feed |
+-----+----+ +----------+ +--------+
^
|
+------+------+
| Rule |
+------+------+
^
|
+----------------+----------------+
| | |
+------+------+ +------+------+ +------+------+
| Event | | Condition | | Action |
+-------------+ +-------------+ +-------------+
Data models are defined at a lower level of abstraction and provide many details. They provide details about the implementation of a protocol's specification, e.g., rules that explain how to map managed objects onto lower-level protocol constructs. Since conceptual models can be implemented in different ways, multiple data models can be derived from a single information model.¶
The efficient and flexible provisioning of network functions by a Network Functions Virtualization (NFV) system leads to a rapid advance in the network industry. As practical applications, Network Security Functions (NSFs), such as firewall, Intrusion Detection System (IDS)/Intrusion Prevention System (IPS), and attack mitigation, can also be provided as Virtual Network Functions (VNF) in the NFV system. By the efficient virtualization technology, these VNFs might be automatically provisioned and dynamically migrated based on real-time security requirements. This document presents a YANG data model to implement security functions based on NFV.¶
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].¶
A Policy object represents a mechanism to express a Security Policy by Security Administrator (i.e., I2NSF User) using Consumer-Facing Interface toward Security Controller; the policy would be enforced on an NSF. Figure 2 shows the YANG tree of the Policy object. The Policy object SHALL have the following information:¶
+--rw i2nsf-cfi-policy* [name]
+--rw name string
+--rw resolution-strategy? identityref
+--rw rules* [name]
| ...
+--rw endpoint-groups
| ...
+--rw threat-preventions
| ...
+--rw url-group* [name]
| ...
A policy is a list of rules. In order to express a Rule, a Rule must have complete information such as where and when a policy needs to be applied. This is done by defining a set of managed objects and relationship among them. A Policy Rule may be related segmentation, threat mitigation or telemetry data collection from an NSF in the network, which will be specified as the sub-model of the policy model in the subsequent sections. Figure 3 shows the YANG data tree of the Rule object. The rule object SHALL have the following information:¶
+--rw rules* [name]
| +--rw name string
| +--rw priority? uint8
| +--rw event
| ...
| +--rw condition
| ...
| +--rw actions
...
Note that in the case of policy conflicts, the resolution of the conflicted policies conforms to the guidelines of "Information Model of NSFs Capabilities" [I-D.ietf-i2nsf-capability].¶
The Event Object contains information related to scheduling a Rule. The Rule could be activated based on a set time or security event. Figure 4 shows the YANG tree of the Event object. Event object SHALL have following information:¶
+--rw event | +--rw security-event? identityref | +--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* day | | +--rw date* int32 | | +--rw month* string | +--rw frequency? enumeration
This object represents Conditions that Security Administrator wants to apply the checking on the traffic in order to determine whether the set of actions in the Rule can be executed or not. The Condition Sub-model consists of three different types of containers each representing different cases, such as general firewall and DDoS-mitigation cases, and a case when the condition is based on the payload strings of packets. Each containers have source and destination-target to represent the source and destination for each case. Figure 5 shows the YANG tree of the Condition object. The Condition Sub-model SHALL have following information:¶
+--rw condition
| +--rw firewall-condition
| | +--rw source* union
| | +--rw destination* union
| | +--rw transport-layer-protocol? identityref
| | +--rw range-port-number
| | | +--rw start-port-number? inet:port-number
| | | +--rw end-port-number? inet:port-number
| | +--rw icmp* [version]
| | +--rw version enumeration
| | +--rw type* uint8
| | +--rw code* uint8
| +--rw ddos-condition
| | +--rw rate-limit
| | +--rw packet-rate-threshold? uint32
| | +--rw byte-rate-threshold? uint64
| | +--rw flow-rate-threshold? uint32
| +--rw anti-virus-condition
| | +--rw exception-files* string
| +--rw payload-condition
| | +--rw content*
-> /i2nsf-cfi-policy/threat-preventions/payload-content/name
| +--rw url-condition
| | +--rw url-name?
-> /i2nsf-cfi-policy/endpoint-groups/url-group/name
| +--rw voice-condition
| | +--rw source-id* string
| | +--rw destination-id* string
| | +--rw user-agent* string
| +--rw context-condition
| +--rw geographic-location
| +--rw source*
-> /i2nsf-cfi-policy/endpoint-groups/location-group/name
| +--rw destination*
-> /i2nsf-cfi-policy/endpoint-groups/location-group/name
| | +--rw threat-feed-condition
| | +--rw name*
-> /i2nsf-cfi-policy/threat-preventions/threat-feed-list/name
This object represents actions that Security Admin wants to perform based on certain traffic class. Figure 6 shows the YANG tree of the Action object. The Action object SHALL have following information:¶
+--rw actions
| +--rw primary-action
| | +--rw action? identityref
| +--rw secondary-action
| +--rw log-action? identityref
The Policy Endpoint Group is a very important part of building User-Construct based policies. A Security Administrator would create and use these objects to represent a logical entity in their business environment, where a Security Policy is to be applied. There are multiple managed objects that constitute a Policy's Endpoint Group, as shown in Figure 7. Figure 8 shows the YANG tree of the Endpoint-Groups object. This section lists these objects and relationship among them.¶
It is assumed that the information of Endpoint Groups (e.g., User-group, Device-group, and Location-group) such as the IP address(es) of each member in a group are stored in the I2NSF database available to the Security Controller, and that the IP address information of each group in the I2NSF database is synchronized with other systems in the networks under the same administration.¶
+-------------------+
| Endpoint Groups |
+---------+---------+
^
|
+--------------+-------+--------+---------------+
0..n | 0..n | 0..n | 0..n |
+-----+----+ +------+-----+ +-------+------+ +-----+---+
|User-group| |Device-group| |Location-group| |Url-group|
+----------+ +------------+ +--------------+ +---------+
+--rw endpoint-groups | +--rw user-group* [name] | ... | +--rw device-group* [name] | ... | +--rw location-group* [name] | ... | +--rw url-group* [name] | ...
This object represents a User-Group. Figure 9 shows the YANG tree of the User-Group object. The User-Group object SHALL have the following information:¶
+--rw user-group* [name] | +--rw name string | +--rw mac-address* yang:mac-address | +--rw (match-type) | | +--:(range-match-ipv4) | | | +--rw range-ipv4-address | | | +--rw start-ipv4-address inet:ipv4-address-no-zone | | | +--rw end-ipv4-address inet:ipv4-address-no-zone | | +--:(range-match-ipv6) | | +--rw range-ipv6-address | | +--rw start-ipv6-address inet:ipv6-address-no-zone | | +--rw end-ipv6-address inet:ipv6-address-no-zone
This object represents a Device-Group. Figure 10 shows the YANG tree of the Device-group object. The Device-Group object SHALL have the following information:¶
+--rw device-group* [name] | +--rw name string | +--rw (match-type) | | +--:(range-match-ipv4) | | | +--rw range-ipv4-address | | | +--rw start-ipv4-address inet:ipv4-address-no-zone | | | +--rw end-ipv4-address inet:ipv4-address-no-zone | | +--:(range-match-ipv6) | | +--rw range-ipv6-address | | +--rw start-ipv6-address inet:ipv6-address-no-zone | | +--rw end-ipv6-address inet:ipv6-address-no-zone | +--rw application-protocol* identityref
This object represents a location group based on either tag or other information. Figure 11 shows the YANG tree of the Location-Group object. The Location-Group object SHALL have the following information:¶
+--rw location-group* [name]
| +--rw name string
| +--rw geo-ip-ipv4* [ipv4-address]
| | +--rw ipv4-address inet:ipv4-address-no-zone
| | +--rw ipv4-prefix? inet:ipv4-prefix
| +--rw geo-ip-ipv6* [ipv6-address]
| | +--rw ipv6-address inet:ipv6-address-no-zone
| | +--rw ipv6-prefix? inet:ipv6-prefix
| +--rw continent? identityref
This object represents a URL group based on a Uniform Resource Locator (URL) or web address. Figure 12 shows the YANG tree of the URL-Group object. The URLn-Group object SHALL have the following information:¶
+--rw url-group* [name]
+--rw name string
+--rw url* string
The threat prevention plays an important part in the overall security posture by reducing the attack surfaces. This information could come from various threat feeds (i.e., sources for obtaining the threat information). There are multiple managed objects that constitute this category. This section lists these objects and relationship among them. Figure 14 shows the YANG tree of a Threat-Prevention object.¶
+-------------------+
| Threat Prevention |
+---------+---------+
^
|
+---------+---------+
0..n | 0..n |
+------+------+ +--------+--------+
| Threat-feed | | payload-content |
+-------------+ +-----------------+
+--rw threat-prevention
+--rw threat-feed-list* [name]
...
+--rw payload-content* [name]
...
This object represents a threat feed which provides the signatures of malicious activities. Figure 15 shows the YANG tree of a Threat-feed-list. The Threat-Feed object SHALL have the following information:¶
It is assumed that the I2NSF User obtains the threat signatures (i.e., threat content patterns) from a threat-feed server (i.e., feed provider), which is a server providing threat signatures. With the obtained threat signatures, the I2NSF User can deliver them to the Security Controller. The retrieval of the threat signatures by the I2NSF User is out of scope in this document.¶
+--rw threat-prevention
+--rw threat-feed-list* [name]
+--rw name identityref
+--rw description? string
+--rw signatures* identityref
This object represents a custom list created for the purpose of defining an exception to threat feeds. Figure 16 shows the YANG tree of a Payload-content list. The Payload-Content object SHALL have the following information:¶
+--rw payload-content* [name]
+--rw name string
+--rw description string
+--rw content* string
Network Configuration Access Control Model (NACM) provides a user group with an access control with the following features [RFC8341]:¶
The data model of the I2NSF Consumer-Facing Interface utilizes the NACM's mechanisms to manage the access control on the I2NSF Consumer-Facing Interface. The NACM with the above features can be used to set up the access control rules of a user group in the I2NSF Consumer-Facing Interface.¶
Figure 17 shows part of the NACM module to enable the access control of a user group for the I2NSF Consumer-Facing Interface. To use the NACM, a user needs to configure either a NETCONF server [RFC6241] or a RESTCONF server [RFC8040] to enable the NACM module. Then, the user can simply use an account of root or admin user for the access control for the module of the I2NSF Consumer-Facing Interface (i.e., ietf-i2nsf-cfi-policy). An XML example to configure the access control a user group for the I2NSF Consumer-Facing Interface can be seen in Section 9.¶
list rule {
key "name";
ordered-by user;
leaf name {
type string {
length "1..max";
}
description
"Arbitrary name assigned to the rule.";
}
leaf module-name {
type union {
type matchall-string-type;
type string;
}
default "*";
description
"Name of the module associated with this rule."
}
leaf access-operations {
type union {
type matchall-string-type;
type access-operations-type;
}
default "*";
description
"Access operations associated with this rule."
}
leaf action {
type action-type;
mandatory true;
description
"The access control action associated with the
rule. If a rule is determined to match a
particular request, then this object is used
to determine whether to permit or deny the
request.";
}
The main objective of this document is to provide both an information model and the corresponding YANG data model of I2NSF Consumer-Facing Interface. This interface can be used to deliver control and management messages between an I2NSF User and Security Controller for the I2NSF User's high-level security policies.¶
The semantics of the data model must be aligned with the information model of the Consumer-Facing Interface. The transformation of the information model is performed so that this YANG data model can facilitate the efficient delivery of the control or management messages.¶
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 Consumer-Facing Interface, this document suggests use cases for security policy rules such as time-based firewall, VoIP/VoLTE security service, and DDoS-attack mitigation in Section 8.¶
This section describes a YANG module of Consumer-Facing Interface. This document provides identities in the data model to be used for configuration of an NSF. Each identity is used for a different type of configuration. The details are explained in the description of each identity. This YANG module imports from [RFC6991]. It makes references to [RFC0768][RFC0792][RFC0793] [RFC0854][RFC0959][RFC1939] [RFC2818][RFC3022][RFC3261] [RFC3501][RFC4250][RFC4340] [RFC4443][RFC4960][RFC5321] [RFC7230][RFC7231][RFC8335] [RFC8805][I-D.ietf-i2nsf-capability] [I-D.ietf-tcpm-rfc793bis][IANA-ICMP-Parameters] [IANA-ICMPv6-Parameters][Encyclopedia-Britannica] [STIX].¶
<CODE BEGINS> file "ietf-i2nsf-cfi-policy@2022-01-28.yang"
module ietf-i2nsf-cfi-policy {
yang-version 1.1;
namespace
"urn:ietf:params:xml:ns:yang:ietf-i2nsf-cfi-policy";
prefix nsfcfi;
import ietf-inet-types{
prefix inet;
reference "RFC 6991";
}
import ietf-yang-types{
prefix yang;
reference "RFC 6991";
}
organization
"IETF I2NSF (Interface to Network Security Functions)
Working Group";
contact
"WG Web: <https://datatracker.ietf.org/wg/i2nsf>
WG List: <mailto:i2nsf@ietf.org>
Editor: Jaehoon Paul Jeong
<mailto:pauljeong@skku.edu>
Editor: Patrick Lingga
<mailto:patricklink@skku.edu>";
description
"This module is a YANG module for Consumer-Facing Interface.
Copyright (c) 2022 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.";
// RFC Ed.: replace XXXX with an actual RFC number and remove
// this note.
revision "2022-01-28" {
description "Initial revision.";
reference
"RFC XXXX: I2NSF Consumer-Facing Interface YANG Data Model";
// RFC Ed.: replace XXXX with an actual RFC number and remove
// this note.
}
identity resolution-strategy {
description
"Base identity for resolution strategy";
reference
"draft-ietf-i2nsf-capability-data-model-22:
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-22:
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-22:
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-22:
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-22:
I2NSF Capability YANG Data Model - Resolution Strategy";
}
identity pmrn {
base resolution-strategy;
description
"Identity for Prioritized Matching Rule
with No Errors (PMRN)";
reference
"draft-ietf-i2nsf-capability-data-model-22:
I2NSF Capability YANG Data Model - Resolution Strategy";
}
identity security-event {
description
"Base identity for security event types.";
}
identity anti-ddos {
base security-event;
description
"Identity for Anti-DDoS event types.";
}
identity ips {
base security-event;
description
"Identity for Intrusion Prevention System event types.";
}
identity url-filtering {
base security-event;
description
"Identity for url-filtering event types.";
}
identity anti-virus {
base security-event;
description
"Identity for Antivirus types.";
}
identity voip-volte-filtering {
base security-event;
description
"Identity for VoIP/VoLTE Filtering event types.";
}
identity protocol {
description
"This identity represents the protocol types.";
}
identity transport-protocol {
base protocol;
description
"Base identity for the Layer 4 (i.e., Transport Layer)
Protocols";
}
identity tcp {
base transport-protocol;
description
"Base identity for TCP condition capabilities";
reference
"RFC 793: Transmission Control Protocol
draft-ietf-tcpm-rfc793bis: Transmission Control Protocol
(TCP) Specification";
}
identity udp {
base transport-protocol;
description
"Base identity for UDP condition capabilities";
reference
"RFC 768: User Datagram Protocol";
}
identity sctp {
base transport-protocol;
description
"Identity for SCTP condition capabilities";
reference
"RFC 4960: Stream Control Transmission Protocol";
}
identity dccp {
base transport-protocol;
description
"Identity for DCCP condition capabilities";
reference
"RFC 4340: Datagram Congestion Control Protocol";
}
identity application-protocol {
base protocol;
description
"Base identity for the Layer 7 (i.e., Application Layer)
Protocols";
}
identity ftp {
base application-protocol;
description
"The identity for ftp protocol.";
reference
"RFC 959: File Transfer Protocol (FTP)";
}
identity ssh {
base application-protocol;
description
"The identity for ssh protocol.";
reference
"RFC 4250: The Secure Shell (SSH) Protocol";
}
identity telnet {
base application-protocol;
description
"The identity for telnet.";
reference
"RFC 854: Telnet Protocol";
}
identity smtp {
base application-protocol;
description
"The identity for smtp.";
reference
"RFC 5321: Simple Mail Transfer Protocol (SMTP)";
}
identity http {
base application-protocol;
description
"The identity for http.";
reference
"RFC7230: Hypertext Transfer Protocol (HTTP/1.1): Message
Syntax and Routing
RFC7231: Hypertext Transfer Protocol (HTTP/1.1): Semantics
and Content";
}
identity https {
base application-protocol;
description
"The identity for https.";
reference
"RFC 2818: HTTP over TLS (HTTPS)";
}
identity pop3 {
base application-protocol;
description
"The identity for pop3.";
reference
"RFC 1939: Post Office Protocol - Version 3 (POP3)";
}
identity imap {
base application-protocol;
description
"The identity for Internet Message Access Protocol (IMAP).";
reference
"RFC 3501: INTERNET MESSAGE ACCESS PROTOCOL - VERSION 4rev1";
}
identity action {
description
"Base identity for action";
}
identity primary-action {
base action;
description
"Base identity for primary action. Primary action is an action
that handle the forwarding of the packets or flows in an
NSF.";
}
identity secondary-action {
base action;
description
"Base identity for secondary action. Secondary action is an
action in the background that does not affect the network,
such as logging.";
}
identity ingress-action {
base primary-action;
description
"Base identity to represents the ingress actions, such as
pass, drop, reject, rate-limit, and mirror.";
}
identity egress-action {
base primary-action;
description
"Base identity represents the egress actions, such as
pass, drop, reject, rate-limit, mirror, invoke-signaling,
tunnel-encapsulation, forwarding, and transformation.";
}
identity pass {
base ingress-action;
base egress-action;
description
"Identity for pass. The pass action allows traffic that matches
the rule to proceed through the NSF to reach the
destination.";
reference
"draft-ietf-i2nsf-capability-data-model-22:
I2NSF Capability YANG Data Model - Actions and
Default Action";
}
identity drop {
base ingress-action;
base egress-action;
description
"Identity for drop. The drop action denies the traffic that
matches the rule. The drop action should do a silent drop,
which does not give any response to the source.";
reference
"draft-ietf-i2nsf-capability-data-model-22:
I2NSF Capability YANG Data Model - Actions and
Default Action";
}
identity reject {
base ingress-action;
base egress-action;
description
"Identity for reject action. The reject action
denies packet to go through the NSF entering or exiting the
internal network and send a response back to the source.
The response depends on the packet and implementation.
For example, a TCP packet is rejected with TCP RST response
or a UDP packet may be rejected with an ICMP response message
with Type 3 Code 3, i.e., Destination Unreachable: Destination
port unreachable.";
reference
"draft-ietf-i2nsf-capability-data-model-22:
I2NSF Capability YANG Data Model - Actions and
Default Action";
}
identity mirror {
base ingress-action;
base egress-action;
description
"Identity for mirror. The mirror action copies a packet and
sends the packet's copy to the monitoring entity while still
allowing the packet or flow to go through the NSF.";
reference
"draft-ietf-i2nsf-capability-data-model-22:
I2NSF Capability YANG Data Model - Actions and
Default Action";
}
identity rate-limit {
base ingress-action;
base egress-action;
description
"Identity for rate limiting action. The rate limit action
limits the number of packets or flows that can go through the
NSF by dropping packets or flows (randomly or
systematically). The drop mechanism, e.g., silent drop and
unreachable drop (i.e., reject), is up to the implementation";
reference
"draft-ietf-i2nsf-capability-data-model-22:
I2NSF Capability YANG Data Model - Actions and
Default Action";
}
identity invoke-signaling {
base egress-action;
description
"Identity for invoke signaling action capability. The invoke
signaling action is used to convey information of the event
triggering this action to a monitoring entity";
reference
"RFC 8329: Framework for Interface to Network Security
Functions - Invoke-signaling action";
}
identity tunnel-encapsulation {
base egress-action;
description
"Identity for tunnel encapsulation action capability. The
tunnel encapsulation action is used to encapsulate the packet
to be tunneled across the network to enable a secure
connection.";
reference
"RFC 8329: Framework for Interface to Network Security
Functions - Tunnel Encapsulation";
}
identity forwarding {
base egress-action;
description
"Identity for forwarding action capability. The forwarding
action is used to relay the packet from one network segment
to another node in the network.";
reference
"RFC 8329: Framework for Interface to Network Security
Functions - Forwarding action";
}
identity transformation {
base egress-action;
description
"Identity for transformation action capability. The
transformation action is used to transform the packet by
modifying its protocol header such as HTTP-to-CoAP
translation.";
reference
"RFC 8329: Framework for Interface to Network Security
Functions - Redirection action";
}
identity log-action {
base secondary-action;
description
"Base identity for representing log actions, such as rule-log
and session-log action.";
}
identity rule-log {
base log-action;
description
"Identity for rule log-action capability.
Log the received packet based on the rule";
}
identity session-log {
base log-action;
description
"Identity for session log-action capability.
Log the received packet based on the session.";
}
identity signature-type {
description
"This represents the base identity for signature types.";
}
identity signature-yara {
base signature-type;
description
"This represents the YARA signatures.";
reference
"YARA: YARA signatures are explained.";
}
identity signature-snort {
base signature-type;
description
"This represents the SNORT signatures.";
reference
"SNORT: SNORT signatures are explained.";
}
identity signature-suricata {
base signature-type;
description
"This represents the SURICATA signatures.";
reference
"SURICATA: SURICATA signatures are explained.";
}
identity threat-feed-type {
description
"This represents the base identity for threat-feed.";
}
identity continent {
description
"Base identity for continent types. The continents are based
on Encyclopedia Britannica";
reference
"Encyclopedia Britannica: Continent";
}
identity africa {
base continent;
description
"Identity for Africa.";
reference
"Encyclopedia Britannica: Continent";
}
identity asia {
base continent;
description
"Identity for Asia.";
reference
"Encyclopedia Britannica: Continent";
}
identity antarctica {
base continent;
description
"Identity for Antarctica.";
reference
"Encyclopedia Britannica: Continent";
}
identity europe {
base continent;
description
"Identity for Europe.";
reference
"Encyclopedia Britannica: Continent";
}
identity north-america {
base continent;
description
"Identity for North America.";
reference
"Encyclopedia Britannica: Continent";
}
identity south-america {
base continent;
description
"Identity for South America.";
reference
"Encyclopedia Britannica: Continent";
}
identity australia {
base continent;
description
"Identity for Australia";
reference
"Encyclopedia Britannica: Continent";
}
/*
* 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.";
}
typedef day {
type enumeration {
enum monday {
description
"This represents Monday.";
}
enum tuesday {
description
"This represents Tuesday.";
}
enum wednesday {
description
"This represents Wednesday";
}
enum thursday {
description
"This represents Thursday.";
}
enum friday {
description
"This represents Friday.";
}
enum saturday {
description
"This represents Saturday.";
}
enum sunday {
description
"This represents Sunday.";
}
}
description
"The type for representing the day of the week.";
}
/*
* Groupings
*/
grouping ipv4-list {
description
"Grouping for an IPv4 address list.";
leaf-list ipv4 {
type inet:ipv4-address-no-zone;
description
"This is the entry for an IPv4 address list.";
}
}
grouping ipv6-list {
description
"Grouping for an IPv6 address list.";
leaf-list ipv6 {
type inet:ipv6-address-no-zone;
description
"This is the entry for an IPv6 address list.";
}
}
grouping ipv4 {
description
"Grouping for an IPv4 address.";
leaf ipv4 {
type inet:ipv4-address-no-zone;
description
"This is the entry for an IPv4 address.";
}
}
grouping ipv6 {
description
"Grouping for an IPv6 address.";
leaf ipv6 {
type inet:ipv6-address-no-zone;
description
"This is the entry for an IPv6 address.";
}
}
grouping ip-address-info {
description
"There are two types to configure a security policy
for an IP address, such as IPv4 adress and IPv6 address.";
choice match-type {
description
"User can choose between IPv4 and IPv6.";
case range-match-ipv4 {
container range-ipv4-address {
leaf start-ipv4-address {
type inet:ipv4-address-no-zone;
mandatory true;
description
"A start IPv4 address for a range match.";
}
leaf end-ipv4-address {
type inet:ipv4-address-no-zone;
mandatory true;
description
"An end IPv4 address for a range match.";
}
description
"A range match for IPv4 addresses is provided.
Note that the start IPv4 address must be lower than
the end IPv4 address.";
}
}
case range-match-ipv6 {
container range-ipv6-address {
leaf start-ipv6-address {
type inet:ipv6-address-no-zone;
mandatory true;
description
"A start IPv6 address for a range match.";
}
leaf end-ipv6-address {
type inet:ipv6-address-no-zone;
mandatory true;
description
"An end IPv6 address for a range match.";
}
description
"A range match for IPv6 addresses is provided.
Note that the start IPv6 address must be lower than
the end IPv6 address.";
}
}
}
}
grouping user-group {
description
"This group represents user group information such as name and
ip-address.";
leaf name {
type string;
description
"This represents the name of a user-group. A user-group name
is used to map a user-group's name (e.g., employees) to IP
address(es), MAC address(es).
It is dependent on implementation.";
}
leaf-list mac-address {
type yang:mac-address;
description
"Represent the MAC Address of a user-group. A user-group
can have multiple MAC Addresses.";
}
uses ip-address-info{
description
"This represents the IP addresses of a user-group.";
refine match-type{
mandatory true;
}
}
}
grouping device-group {
description
"This group represents device group information such as
ip-address protocol.";
leaf name {
type string;
description
"This represents the name of a device-group.";
}
uses ip-address-info{
refine match-type{
mandatory true;
}
}
leaf-list application-protocol {
type identityref {
base application-protocol;
}
description
"This represents the application layer protocols of devices.
If this is not set, it cannot support the appropriate
protocol";
}
}
grouping location-group {
description
"This group represents location-group information such as
geo-ip and continent.";
leaf name {
type string;
description
"This represents the name of a location.";
}
list geo-ip-ipv4 {
key "ipv4-address";
description
"This represents the list of IPv4 addresses based on a
location.";
leaf ipv4-address{
type inet:ipv4-address-no-zone;
description
"This represents an IPv4 geo-ip address of a location.";
}
leaf ipv4-prefix{
type inet:ipv4-prefix;
description
"This represents the prefix for the IPv4 addresses.";
}
}
list geo-ip-ipv6 {
key "ipv6-address";
description
"This represents the list of IPv6 addresses based on a
location.";
leaf ipv6-address{
type inet:ipv6-address-no-zone;
description
"This represents an IPv6 geo-ip address of a location.";
}
leaf ipv6-prefix{
type inet:ipv6-prefix;
description
"This represents the prefix for the IPv6 addresses.";
}
}
leaf continent {
type identityref {
base continent;
}
default asia;
description
"location-group has geo-ip addresses of the corresponding
continent.";
}
reference
"RFC 8805: A Format for Self-Published IP Geolocation Feeds -
An access control for a geographical location (i.e.,
geolocation) that has the corresponding IP prefix.";
}
grouping payload-string {
description
"The grouping for payload-string content. It contains
information such as name and string content.";
leaf description {
type string;
description
"This represents the description of a payload. If this is
not set, it cannot support the description of how the
payload content is related to a security attack.";
}
leaf-list content {
type string;
description
"This represents the string of the payload contents.
This content leaf-list contains the payload of a packet to
analyze a threat. Due to the types of threats, the type of
the content is defined as a string to accommodate any kind
of a payload type such as HTTP, HTTPS, and SIP. If this is
not set, it cannot support the payload contents involved in
a security attack as a string.";
}
}
list i2nsf-cfi-policy {
key "name";
description
"This is a security policy list. Each policy in the list
contains a list of security policy rules, and is a policy
instance to have the information of where and when a policy
needs to be applied.";
leaf name {
type string;
description
"The name which identifies the policy.";
}
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-22:
I2NSF Capability YANG Data Model - Resolution strategy";
}
list rules {
key "name";
description
"There can be a single or multiple number of rules.";
leaf name {
type string;
description
"This represents the name for a rule.";
}
leaf priority {
type uint8 {
range "1..255";
}
description
"The priority keyword comes with a mandatory
numeric value which can range from 1 through 255.
Note that a higher number means a higher priority";
}
container event {
description
"This represents an event (i.e., a security event), for
which a security rule is made.";
leaf security-event {
type identityref {
base security-event;
}
description
"This contains the description of a security event. If
this is not set, it cannot support what security event
will be enforced.";
}
container time {
description
"The time when a security policy rule 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 security policy
rule. The policy rule will stop working after the
specified end date and time.";
}
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 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;
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
enforced only once and not repeated. The policy
will continuously be active from the
start-date-time to the end-date-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-time.";
}
enum weekly {
description
"This represents that the rule is enforced on a
weekly basis. The policy will be repeated weekly
until the end-date-time. 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-time.";
}
enum yearly {
description
"This represents that the rule is enforced on a
yearly basis. The policy will be repeated yearly
until the end-date-time.";
}
}
default only-once;
description
"This represents how frequently the rule should be
enforced.";
}
}
}
container condition {
description
"Conditions for general security policies.";
container firewall-condition {
description
"A general firewall condition based on the packet
header.";
leaf-list source {
type union {
type leafref {
path
"/i2nsf-cfi-policy/endpoint-groups/"
+"user-group/name";
}
type leafref {
path
"/i2nsf-cfi-policy/endpoint-groups/"
+"device-group/name";
}
}
description
"This describes the path of the source.";
}
leaf-list destination {
type union {
type leafref {
path
"/i2nsf-cfi-policy/endpoint-groups/"
+"user-group/name";
}
type leafref {
path
"/i2nsf-cfi-policy/endpoint-groups/"
+"device-group/name";
}
}
description
"This describes the path to the destinations.";
}
leaf transport-layer-protocol {
type identityref {
base transport-protocol;
}
description
"The transport-layer protocol to be matched.";
}
container range-port-number {
leaf start-port-number {
type inet:port-number;
description
"A start port number for range match.";
}
leaf end-port-number {
type inet:port-number;
description
"An end port number for range match.";
}
description
"A range match for transport-layer port number. Note
that the start port number value must be lower than
the end port number value";
}
list icmp {
key "version";
description
"Represents the 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";
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
ICMP type parameter.";
reference
"RFC 792: Internet Control Message Protocol
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
ICMP code parameter.";
reference
"RFC 792: Internet Control Message Protocol
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 ddos-condition {
description
"A condition for a DDoS attack.";
container rate-limit {
description
"This describes the rate-limit.";
leaf packet-rate-threshold {
type uint32;
description
"This is a trigger value for a rate limit of packet
rate for a DDoS-attack mitigation.";
}
leaf byte-rate-threshold {
type uint64;
description
"This is a trigger value for a rate limit of byte
rate for a DDoS-attack mitigation.";
}
leaf flow-rate-threshold {
type uint32;
description
"This is a trigger value for a rate limit of flow
rate for a DDoS-attack mitigation.";
}
}
}
container anti-virus-condition {
description
"A condition for anti-virus";
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-condition {
description
"A condition based on a packet's content.";
leaf-list content {
type leafref {
path "/i2nsf-cfi-policy/threat-preventions/"
+ "payload-content/name";
}
description
"This describes the paths to a packet content's";
}
}
container url-condition {
description
"Condition for url category";
leaf url-name {
type leafref {
path
"/i2nsf-cfi-policy/endpoint-groups/"
+"url-group/name";
}
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.";
}
}
container voice-condition {
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-list source-id {
type string;
description
"The security policy rule according to
a source voice ID for VoIP and VoLTE.";
}
leaf-list destination-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
an user agent for VoIP and VoLTE.";
}
}
container context-condition {
description
"Condition for matching the context of the packet, such
as geographic location, time, packet direction";
container geographic-location {
description
"A condition for a location-based connection";
leaf-list source {
type leafref {
path
"/i2nsf-cfi-policy/endpoint-groups/"
+"location-group/name";
}
description
"This describes the paths to a location's sources.";
}
leaf-list destination {
type leafref {
path
"/i2nsf-cfi-policy/endpoint-groups/"
+"location-group/name";
}
description
"This describes the paths to a location's
destinations.";
}
}
}
container threat-feed-condition {
description
"A condition based on the threat-feed information.";
leaf-list name {
type leafref {
path
"/i2nsf-cfi-policy/threat-preventions/"
+"threat-feed-list/name";
}
description
"This describes the paths to a threat-feed's sources.";
}
}
}
container actions {
description
"This is the action container.";
container primary-action {
description
"This represents primary actions (e.g., ingress and
egress actions) to be applied to a condition.
If this is not set, it cannot support the primary
actions.";
leaf action {
type identityref {
base primary-action;
}
description
"Ingress actions: pass, drop, reject, rate-limit,
and mirror.
Egress actions: mirror, invoke-signaling,
tunnel-encapsulation, forwarding, and redirection.";
}
}
container secondary-action {
description
"This represents secondary actions (e.g., log and syslog)
to be applied if they are needed. If this is not set,
it cannot support the secondary actions.";
leaf log-action {
type identityref {
base secondary-action;
}
description
"Log action: rule log and session log";
}
}
}
}
container endpoint-groups {
description
"A logical entity in a business environment, where a security
policy is to be applied.";
list user-group{
uses user-group;
key "name";
description
"This represents a user group.";
}
list device-group {
key "name";
uses device-group;
description
"This represents a device group.";
}
list location-group{
key "name";
uses location-group;
description
"This represents a location group.";
}
list url-group {
key "name";
description
"This describes the list of URL.";
leaf name {
type string;
description
"This is the name of URL group, e.g., SNS sites,
gaming sites, ecommerce sites";
}
leaf-list url {
type string;
description
"Specifies the URL to be added into the group.";
}
}
}
container threat-preventions {
description
"This describes the list of threat-preventions.";
list threat-feed-list {
key "name";
description
"There can be a single or multiple number of
threat-feeds.";
leaf name {
type string;
description
"This represents the name of the threat-feed.";
}
leaf description {
type string;
description
"This represents the descriptions of a threat-feed. The
description should include information, such as type,
threat, method, and file type. Structured Threat
Information Expression (STIX) can be used for
description of a threat [STIX].";
}
leaf-list signatures {
type identityref {
base signature-type;
}
description
"This contains a list of signatures or hashes of the
threats.";
}
}
list payload-content {
key "name";
leaf name {
type string;
description
"This represents the name of a packet's payload-content.
It should give an idea of why a specific payload content
is marked as a threat. For example, the name 'backdoor'
indicates the payload content is related to a backdoor
attack.";
}
description
"This represents a payload-string group.";
uses payload-string;
}
}
}
}
<CODE ENDS>
This section shows XML configuration examples of high-level security policy rules that are delivered from the I2NSF User to the Security Controller over the Consumer-Facing Interface. The considered use cases are: Database registration, time-based firewall for web filtering, VoIP/VoLTE security service, and DDoS-attack mitigation.¶
If new endpoints are introduced to the network, it is necessary to first register their data to the database. For example, if new members are newly introduced in either of three different groups (i.e., user-group, device-group, and url-group), each of them should be registered with information such as ip-addresses or protocols used by devices.¶
Figure 19 shows an example XML representation of the registered information for the user-group and device-group with IPv4 addresses [RFC5737].¶
<?xml version="1.0" encoding="UTF-8" ?>
<i2nsf-cfi-policy
xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-cfi-policy">
<name>security_policy_for_blocking_sns</name>
<endpoint-groups>
<user-group>
<name>employees</name>
<range-ipv4-address>
<start-ipv4-address>192.0.2.11</start-ipv4-address>
<end-ipv4-address>192.0.2.90</end-ipv4-address>
</range-ipv4-address>
</user-group>
<device-group>
<name>webservers</name>
<range-ipv4-address>
<start-ipv4-address>198.51.100.11</start-ipv4-address>
<end-ipv4-address>198.51.100.20</end-ipv4-address>
</range-ipv4-address>
<application-protocol>nsfcfi:http</application-protocol>
<application-protocol>nsfcfi:https</application-protocol>
</device-group>
<url-group>
<name>sns-websites</name>
<url>SNS_1</url>
<url>SNS_2</url>
</url-group>
</endpoint-groups>
</i2nsf-cfi-policy>
Also, Figure 20 shows an example XML representation of the registered information for the user-group and device-group with IPv6 addresses [RFC3849].¶
<?xml version="1.0" encoding="UTF-8" ?>
<i2nsf-cfi-policy
xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-cfi-policy">
<name>security_policy_for_blocking_sns</name>
<endpoint-groups>
<user-group>
<name>employees</name>
<range-ipv6-address>
<start-ipv6-address>2001:db8:0:1::11</start-ipv6-address>
<end-ipv6-address>2001:db8:0:1::90</end-ipv6-address>
</range-ipv6-address>
</user-group>
<device-group>
<name>webservers</name>
<range-ipv6-address>
<start-ipv6-address>2001:db8:0:2::11</start-ipv6-address>
<end-ipv6-address>2001:db8:0:2::20</end-ipv6-address>
</range-ipv6-address>
<application-protocol>nsfcfi:http</application-protocol>
<application-protocol>nsfcfi:https</application-protocol>
</device-group>
<url-group>
<name>sns-websites</name>
<url>SNS_1</url>
<url>SNS_2</url>
</url-group>
</endpoint-groups>
</i2nsf-cfi-policy>
The first example scenario is to "block SNS access during office hours" using a time-based firewall policy. In this scenario, all users registered as "employees" in the user-group list are unable to access Social Networking Services (SNS) during the office hours (weekdays). The XML instance is described below:¶
<?xml version="1.0" encoding="UTF-8" ?>
<i2nsf-cfi-policy
xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-cfi-policy">
<name>security_policy_for_blocking_sns</name>
<rules>
<name>block_access_to_sns_during_office_hours</name>
<event>
<time>
<start-date-time>2021-03-11T09:00:00.00Z</start-date-time>
<end-date-time>2021-12-31T18:00:00.00Z</end-date-time>
<period>
<start-time>09:00:00Z</start-time>
<end-time>18:00:00Z</end-time>
<day>monday</day>
<day>tuesday</day>
<day>wednesday</day>
<day>thursday</day>
<day>friday</day>
</period>
<frequency>weekly</frequency>
</time>
</event>
<condition>
<firewall-condition>
<source>employees</source>
</firewall-condition>
<url-condition>
<url-name>sns-websites</url-name>
</url-condition>
</condition>
<actions>
<primary-action>
<action>nsfcfi:drop</action>
</primary-action>
</actions>
</rules>
</i2nsf-cfi-policy>
Time-based-condition Firewall¶
The second example scenario is to "block malicious VoIP/VoLTE packets coming to a company" using a VoIP policy. In this scenario, the calls comming from from VOIP and/or VOLTE sources with VOLTE IDs that are classified as malicious are dropped. The IP addresses of the employees and malicious VOIP IDs should be blocked are stored in the database or datastore of the enterprise. Here and the rest of the cases assume that the security administrators or someone responsible for the existing and newly generated policies, are not aware of which and/or how many NSFs are needed to meet the security requirements. Figure 22 represents the XML document generated from YANG discussed in previous sections. Once a high-level seucurity policy is created by a security admin, it is delivered by the Consumer-Facing Interface, through RESTCONF server, to the security controller. The XML instance is described below:¶
<?xml version="1.0" encoding="UTF-8" ?>
<i2nsf-cfi-policy
xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-cfi-policy">
<name>
security_policy_for_blocking_malicious_voip_packets
</name>
<rules>
<name>Block_malicious_voip_and_volte_packets</name>
<condition>
<voice-condition>
<source-id>malicious-id</source-id>
</voice-condition>
<firewall-condition>
<destination>employees</destination>
</firewall-condition>
</condition>
<actions>
<primary-action>
<action>nsfcfi:drop</action>
</primary-action>
</actions>
</rules>
</i2nsf-cfi-policy>
Custom-condition Firewall¶
The third example scenario is to "Mitigate HTTP and HTTPS flood attacks on a company web server" using a DDoS-attack mitigation policy. Here, the time information is not set because the service provided by the network should be maintained at all times. If the packets sent by any sources are more than the set threshold, then the admin can set the percentage of the packets to be dropped to safely maintain the service. In this scenario, the source is set as "any" to block any sources which send abnormal amount of packets. The destination is set as "web_server01". Once the rule is set and delivered and enforced to the nsfs by the securiy controller, the NSFs will monitor the incoming packet amounts and the destination to act according to the rule set. The XML instance is described below:¶
<?xml version="1.0" encoding="UTF-8" ?>
<i2nsf-cfi-policy
xmlns="urn:ietf:params:xml:ns:yang:ietf-i2nsf-cfi-policy">
<name>security_policy_for_ddos_attacks</name>
<rules>
<name>1000_packets_per_second</name>
<condition>
<ddos-condition>
<rate-limit>
<packet-rate-threshold>1000</packet-rate-threshold>
</rate-limit>
</ddos-condition>
</condition>
<actions>
<primary-action>
<action>drop</action>
</primary-action>
</actions>
</rules>
</i2nsf-cfi-policy>
DDoS-condition Firewall¶
This is an example for creating privileges for a group of users (i.e., a user group) to access and use the I2NSF Consumer-Facing Interface to create security policies via the interface. For the access control of the Consumer-Facing Interface, the NACM module can be used. Figure 24 shows an XML example the access control of a user group (named Example-Group) for I2NSF Consumer-Facing Interface A group called Example-Group can be created and configured with NACM for the Consumer-Facing Interface. For Example-Group, a rule list can created with the name of Example-Group-Rules. Example-Group-Rules has two rules of Example-Group-Rule1 and Example-Group-Rule2 as follows. For Example-Group-Rule1, the privilege of "Read" is allowed to Example-Group for the Consumer-Facing Interface. On the other hand, for Example-Group-Rule2, the privileges of "Create", "Update", and "Delete" are denied against Example-Group for the Consumer-Facing Interface.¶
<?xml version="1.0" encoding="UTF-8" ?>
<nacm xmlns="urn:ietf:params:xml:ns:yang:ietf-netconf-acm">
<enable-nacm>true</enable-nacm>
<groups>
<group>
<name>Example-Group</name>
<user-name>Alice</user-name>
<user-name>Bob</user-name>
<user-name>Eve</user-name>
</group>
</groups>
<rule-list>
<name>Example-Group-Rules</name>
<group>Example-Group</group>
<rule>
<name>Example-Group-Rule1</name>
<access-operations>read</access-operations>
<module-name>ietf-i2nsf-cfi-policy</module-name>
<action>permit</action>
</rule>
<rule>
<name>Example-Group-Rule2</name>
<access-operations>create update delete</access-operations>
<module-name>ietf-i2nsf-cfi-policy</module-name>
<action>deny</action>
</rule>
</rule-list>
</nacm>
The access control for the I2NSF Consumer-Facing Interface is as follows.¶
This document requests IANA to register the following URI in the "IETF XML Registry" [RFC3688]:¶
URI: urn:ietf:params:xml:ns:yang:ietf-i2nsf-cfi-policy 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-cfi-policy namespace: urn:ietf:params:xml:ns:yang:ietf-i2nsf-cfi-policy prefix: nsfcfi reference: RFC XXXX // RFC Ed.: replace XXXX with an actual RFC number and remove // this note.¶
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 Network Configuration Access Control Model (NACM) [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 contents. Thus, NACM SHOULD be used to restrict the NSF registration from unauthorized users.¶
There are a number of data nodes defined in this YANG module that are writable, creatable, and deletable (i.e., config true, which is the default). These data nodes may be considered sensitive or vulnerable in some network environments. Write operations to these data nodes could have a negative effect on network and security operations. These data nodes are collected into a single list node with the following sensitivity/vulnerability:¶
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 with their sensitivity/vulnerability:¶
This document is a product by the I2NSF Working Group (WG) including WG Chairs (i.e., Linda Dunbar and Yoav Nir) and Diego Lopez. This document took advantage of the review and comments from the following people: Roman Danyliw, Mahdi F. Dachmehchi, Daeyoung Hyun, Jan Lindblad (YANG doctor), and Tom Petch. We authors sincerely appreciate their sincere efforts and kind help.¶
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).¶
The following are co-authors of this document:¶
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¶
Eunsoo Kim - Department of Electronic, Electrical and Computer Engineering, Sungkyunkwan University, 2066 Seo-ro Jangan-gu, Suwon, Gyeonggi-do 16419, Republic of Korea, EMail: eskim86@skku.edu¶
Seungjin Lee - Department of Electronic, Electrical and Computer Engineering, Sungkyunkwan University, 2066 Seo-ro Jangan-gu, Suwon, Gyeonggi-do 16419, Republic of Korea, EMail: jine33@skku.edu¶
Jinyong (Tim) Kim - Department of Electronic, Electrical and Computer Engineering, Sungkyunkwan University, 2066 Seo-ro Jangan-gu, Suwon, Gyeonggi-do 16419, Republic of Korea, EMail: timkim@skku.edu¶
Anil Lohiya - Juniper Networks, 1133 Innovation Way, Sunnyvale, CA 94089, US, EMail: alohiya@juniper.net¶
Dave Qi - Bloomberg, 731 Lexington Avenue, New York, NY 10022, US, EMail: DQI@bloomberg.net¶
Nabil Bitar - Nokia, 755 Ravendale Drive, Mountain View, CA 94043, US, EMail: nabil.bitar@nokia.com¶
Senad Palislamovic - Nokia, 755 Ravendale Drive, Mountain View, CA 94043, US, EMail: senad.palislamovic@nokia.com¶
Liang Xia - Huawei, 101 Software Avenue, Nanjing, Jiangsu 210012, China, EMail: Frank.Xialiang@huawei.com¶
The following changes are made from draft-ietf-i2nsf-consumer-facing-interface-dm-15:¶