Network Working Group M. Bjorklund Internet-Draft Tail-f Systems Intended status: Standards Track February 8, 2012 Expires: August 11, 2012 A YANG Data Model for IP Configuration draft-ietf-netmod-ip-cfg-02 Abstract This document defines a YANG data model for configuration of IP addresses on network interfaces. 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 http://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 August 11, 2012. Copyright Notice Copyright (c) 2012 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 (http://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 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. Bjorklund Expires August 11, 2012 [Page 1] Internet-Draft YANG IP Configuration February 2012 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. IP Data Model . . . . . . . . . . . . . . . . . . . . . . . . 4 3. IP Address YANG Module . . . . . . . . . . . . . . . . . . . . 5 4. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 5. Security Considerations . . . . . . . . . . . . . . . . . . . 11 6. Normative References . . . . . . . . . . . . . . . . . . . . . 12 Appendix A. Example: NETCONF reply . . . . . . . . . . . . 13 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 14 Bjorklund Expires August 11, 2012 [Page 2] Internet-Draft YANG IP Configuration February 2012 1. Introduction This document defines a YANG [RFC6020] data model for configuration of IP addresses on network interfaces. The keywords "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]. Bjorklund Expires August 11, 2012 [Page 3] Internet-Draft YANG IP Configuration February 2012 2. IP Data Model The module "ietf-ip" augments the "interface" list defined in the "ietf-interfaces" module [I-D.ietf-netmod-interfaces-cfg] with the following nodes, where square brackets are used to enclose a list's keys, and "?" means that the node is optional. Choice and case nodes are enclosed in parenthesis, and a case node is marked with a colon (":"). +--rw if:interfaces +--rw if:interface [name] ... +--rw ipv4 | +--rw enabled? boolean | +--rw address [ip] | +--rw ip inet:ipv4-address | +--rw (subnet)? | +--:(prefix-length) | | +--rw ip:prefix-length? uint8 | +--:(netmask) | +--rw ip:netmask? inet:ipv4-address +--rw ipv6 +--rw enabled? boolean +--rw address [ip] | +--rw ip inet:ipv6-address | +--rw prefix-length? uint8 +--rw autoconf +--rw create-global-addresses? boolean +--rw dup-addr-detect-transmits? uint32 The data model defines two containers, "ipv4" and "ipv6", representing the IPv4 and IPv6 address families. In each container, there is a leaf "enabled" that controls if the address familiy is enabled on that interface. In each container, there is also a list of manually configured addresses. Bjorklund Expires August 11, 2012 [Page 4] Internet-Draft YANG IP Configuration February 2012 3. IP Address YANG Module This module imports typedefs from [RFC6021] and [I-D.ietf-netmod-interfaces-cfg], and references [RFC4862]. RFC Ed.: update the date below with the date of RFC publication and remove this note. file "ietf-ip@2012-02-08.yang" module ietf-ip { namespace "urn:ietf:params:xml:ns:yang:ietf-ip"; prefix ip; import ietf-interfaces { prefix if; } import ietf-inet-types { prefix inet; } organization "IETF NETMOD (NETCONF Data Modeling Language) Working Group"; contact "WG Web: WG List: WG Chair: David Kessens WG Chair: Juergen Schoenwaelder Editor: Martin Bjorklund "; description "This module contains a collection of YANG definitions for configuring IP addresses on network interfaces. Copyright (c) 2011 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 Bjorklund Expires August 11, 2012 [Page 5] Internet-Draft YANG IP Configuration February 2012 set forth in Section 4.c of the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info). This version of this YANG module is part of RFC XXXX; see the RFC itself for full legal notices."; // RFC Ed.: replace XXXX with actual RFC number and remove this // note. // RFC Ed.: update the date below with the date of RFC publication // and remove this note. revision 2012-02-08 { description "Initial revision."; reference "RFC XXXX: A YANG Data Model for IP Configuration"; } /* Features */ feature non-contiguous-netmasks { description "Indicates support for configuring non-contiguous subnet masks."; } /* Data nodes */ augment "/if:interfaces/if:interface" { description "Parameters for configuring IP addresses on interfaces. If an interface is not capable of running IP, the server must not allow the client to configure these parameters."; container ipv4 { description "Parameters for the IPv4 address family."; leaf enabled { type boolean; default true; description "Controls if IPv4 is enabled or disabled on this interface."; } list address { key "ip"; Bjorklund Expires August 11, 2012 [Page 6] Internet-Draft YANG IP Configuration February 2012 description "The list of manually configured IPv4 addresses on the interface."; leaf ip { type inet:ipv4-address; description "The IPv4 address on the interface."; } choice subnet { default prefix-length; description "The subnet can be specified as a prefix-length, or, if the server supports non-contiguous netmasks, as a netmask. The default subnet is a prefix-length of 32."; leaf prefix-length { type uint8 { range "0..32"; } default 32; description "The length of the subnet prefix."; } leaf netmask { if-feature non-contiguous-netmasks; type inet:ipv4-address; description "The subnet specified as a netmask."; } } } } container ipv6 { description "Parameters for the IPv6 address family."; leaf enabled { type boolean; default true; description "Controls if IPv6 is enabled or disabled on this interface."; } list address { key "ip"; description Bjorklund Expires August 11, 2012 [Page 7] Internet-Draft YANG IP Configuration February 2012 "The list of manually configured IPv6 addresses on the interface."; leaf ip { type inet:ipv6-address; description "The IPv6 address on the interface."; } leaf prefix-length { type uint8 { range "0..128"; } default 128; description "The length of the subnet prefix."; } } container autoconf { description "Parameters to control the autoconfiguration of IPv6 addresses, as described in RFC 4862."; reference "RFC 4862: IPv6 Stateless Address Autoconfiguration"; // Open Issue #ip-02: should we have a leaf to control // the creation of a link-local address? //leaf create-link-local-address { ... default true; ... } leaf create-global-addresses { // Open Issue #ip-06: should we have a feature here? //if-feature ipv6-host; type boolean; default true; description "If enabled, the host creates global addresses as described in section 5.5 of RFC 4862."; reference "RFC 4862: IPv6 Stateless Address Autoconfiguration"; } leaf dup-addr-detect-transmits { type uint32; default 1; description "The number of consecutive Neighbor Solicitation messages sent while performing Duplicate Address Detection on a tentative address. A value of zero indicates that Duplicate Address Detection is not performed on tentative addresses. A value of one indicates a single Bjorklund Expires August 11, 2012 [Page 8] Internet-Draft YANG IP Configuration February 2012 transmission with no follow-up retransmissions."; reference "RFC 4862: IPv6 Stateless Address Autoconfiguration"; } } } } } Bjorklund Expires August 11, 2012 [Page 9] Internet-Draft YANG IP Configuration February 2012 4. IANA Considerations This document registers a URI in the IETF XML registry [RFC3688]. Following the format in RFC 3688, the following registration is requested to be made. URI: urn:ietf:params:xml:ns:yang:ietf-ip Registrant Contact: The NETMOD WG of the IETF. XML: N/A, the requested URI is an XML namespace. This document registers a YANG module in the YANG Module Names registry [RFC6020]. name: ietf-ip namespace: urn:ietf:params:xml:ns:yang:ietf-ip prefix: ip reference: RFC XXXX Bjorklund Expires August 11, 2012 [Page 10] Internet-Draft YANG IP Configuration February 2012 5. Security Considerations The YANG module defined in this memo is designed to be accessed via the NETCONF protocol [RFC6241]. The lowest NETCONF layer is the secure transport layer and the mandatory-to-implement secure transport is SSH [RFC6242]. There are a number of data nodes defined in the YANG module which are writable/creatable/deletable (i.e., config true, which is the default). These data nodes may be considered sensitive or vulnerable 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: ipv4/enabled and ipv6/enabled: These nodes are used to enable or disable IPv4 and IPv6 on a specific interface. By enabling a protocol on an interface, an attacker might be able to create an unsecured path into a node (or through it if routing is also enabled). By disabling a protocol on an interface, an attacker might be able to force packets to be routed through some other interface or deny access to some or all of the network via that protocol. ipv4/address and ipv6/address: These lists specify the configured IP addresses on an interface. By modifying this information, an attacker can cause a node to either ignore messages destined to it or accept (at least at the IP layer) messages it would otherwise ignore. The use of filtering or security associations may reduce the potential damage in the latter case. Bjorklund Expires August 11, 2012 [Page 11] Internet-Draft YANG IP Configuration February 2012 6. Normative References [I-D.ietf-netmod-interfaces-cfg] Bjorklund, M., "A YANG Data Model for Interface Configuration", draft-ietf-netmod-interfaces-cfg-01 (work in progress), May 2011. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, January 2004. [RFC4862] Thomson, S., Narten, T., and T. Jinmei, "IPv6 Stateless Address Autoconfiguration", RFC 4862, September 2007. [RFC6020] Bjorklund, M., "YANG - A Data Modeling Language for the Network Configuration Protocol (NETCONF)", RFC 6020, October 2010. [RFC6021] Schoenwaelder, J., "Common YANG Data Types", RFC 6021, October 2010. [RFC6241] Enns, R., Bjorklund, M., Schoenwaelder, J., and A. Bierman, "Network Configuration Protocol (NETCONF)", RFC 6241, June 2011. [RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure Shell (SSH)", RFC 6242, June 2011. Bjorklund Expires August 11, 2012 [Page 12] Internet-Draft YANG IP Configuration February 2012 Appendix A. Example: NETCONF reply This section gives an example of a reply to the NETCONF request for a device that implements the data model defined in this document. eth0 ethernetCsmacd 0 2
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Bjorklund Expires August 11, 2012 [Page 13] Internet-Draft YANG IP Configuration February 2012 Author's Address Martin Bjorklund Tail-f Systems Email: mbj@tail-f.com Bjorklund Expires August 11, 2012 [Page 14]