Babel routing protocol B. Stark Internet-Draft AT&T Intended status: Informational January 2, 2018 Expires: July 6, 2018 Babel Information Model draft-ietf-babel-information-model-01 Abstract This Babel Information Model can be used to create data models under various data modeling regimes (e.g., YANG). It allows a Babel implementation (via a management protocol such as netconf) to report on its current state and may allow some limited configuration of protocol constants. 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 July 6, 2018. Copyright Notice Copyright (c) 2018 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 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. Stark Expires July 6, 2018 [Page 1] Internet-Draft Babel Information Model January 2018 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 1.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 1.2. Notation . . . . . . . . . . . . . . . . . . . . . . . . 3 2. The Information Model . . . . . . . . . . . . . . . . . . . . 4 2.1. Definition of babel-information . . . . . . . . . . . . . 4 2.2. Definition of babel-constants . . . . . . . . . . . . . . 4 2.3. Definition of babel-interfaces . . . . . . . . . . . . . 5 2.4. Definition of babel-neighbors . . . . . . . . . . . . . . 6 2.5. Definition of babel-security . . . . . . . . . . . . . . 6 2.6. Definition of babel-trust . . . . . . . . . . . . . . . . 7 2.7. Definition of babel-sources . . . . . . . . . . . . . . . 7 2.8. Definition of babel-routes . . . . . . . . . . . . . . . 7 3. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 8 4. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 4.1. Normative References . . . . . . . . . . . . . . . . . . 9 4.2. Informative References . . . . . . . . . . . . . . . . . 9 Appendix A. Open Issues . . . . . . . . . . . . . . . . . . . . 10 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 10 1. Introduction Babel is a loop-avoiding distance-vector routing protocol defined in RFC 6126bis [RFC6126bis]. Babel Hashed Message Authentication Code (HMAC) Cryptographic Authentication, defined in RFC 7298 [RFC7298], describes a cryptographic authentication mechanism for the Babel routing protocol. This document describes an information model for Babel (including HMAC) that can be used to created management protocol data models (such as a netconf [RFC6241] YANG data model). Other Babel extensions may be included in this document when they become working group drafts. Due to the simplicity of the Babel protocol and the fact that it is designed to be used in non-professionally administered environments (such as home networks), most of the information model is focused on reporting status of the Babel protocol, and very little of that is considered mandatory to implement (conditional on a management protocol with Babel support being implemented). Some parameters may be configurable; however, it is up to the Babel implementation whether to allow any of these to be configured within its implementation. Where the implementation does not allow configuration of these parameters, it may still choose to expose them as read-only. Stark Expires July 6, 2018 [Page 2] Internet-Draft Babel Information Model January 2018 1.1. Requirements Language The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119 [RFC2119]. 1.2. Notation This document uses a programming language-like notation to define the properties of the objects of the information model. An optional property is enclosed by square brackets, [ ], and a list property is indicated by two numbers in angle brackets, , where m indicates the minimal number of values, and n is the maximum. The symbol * for n means no upper bound. The object definitions use base types that are defined as follows: base64 An opaque array of bytes. boolean A type representing a boolean value. counter A non-negative integer that monotonically increases. Counters may have discontinuities and they are not expected to persist across restarts. credentials An opaque type representing credentials needed by a cryptographic mechanism to secure communication. Data models must expand this opaque type as needed and required by the security protocols utilized. datetime A type representing a date and time using the Gregorian calendar. The datetime format MUST conform to RFC 3339 [RFC3339]. int A type representing signed or unsigned integer numbers. This information model does not define a precision nor does it make a distinction between signed and unsigned number ranges. This type is also used to represent enumerations. ip-address A type representing an IP address. This type supports both IPv4 and IPv6 addresses. string A type representing a human-readable string consisting of a (possibly restricted) subset of Unicode and ISO/IEC 10646 [ISO.10646] characters. Stark Expires July 6, 2018 [Page 3] Internet-Draft Babel Information Model January 2018 uri A type representing a Uniform Resource Identifier as defined in STD 66 [RFC3986]. 2. The Information Model 2.1. Definition of babel-information object { string babel-implementation-version; base64 babel-self-router-id; [int babel-self-seqno;] string babel-cost-comp-algorithms<1..*>; babel-constants-obj babel-constants; babel-interfaces-obj babel-interfaces<0..*>; babel-sources-obj babel-sources<0..*>; babel-routes-obj babel-routes<0..*>; }babel-information-obj; babel-version: the version of this implementation of the Babel protocol babel-self-router-id: the router-id used by this instance of the Babel protocol to identify itself; RFC 6126bis [RFC6126bis] describes this as an arbitrary string of 8 octets babel-self-seqno: the current sequence number included in route updates for routes originated by this node babel-cost-comp-algorithm: a set of names of supported cost computation algorithms; possible values include "k-out-of-j", "ETX" babel-constants: a babel-constants object babel-interfaces: a set of babel-interface objects babel-sources: a set of babel-source objects babel-routes: a set of babel-route objects 2.2. Definition of babel-constants object { int babel-udp-port; [ip-address babel-multicast-group-ipv6;] [ip-address babel-multicast-group-ipv4;] }babel-constants-obj; Stark Expires July 6, 2018 [Page 4] Internet-Draft Babel Information Model January 2018 babel-udp-port: UDP port for sending and listening for Babel messages; default is 6696; MAY be configurable babel-multicast-group-ipv6: multicast group for sending and listening to multicast announcements on IPv6; default is ff02:0:0:0:0:0:1:6; MAY be configurable babel-multicast-group-ipv4: multicast group for sending and listening to multicast announcements on IPv4; default is 224.0.0.111; MAY be configurable 2.3. Definition of babel-interfaces object { uri babel-interface-reference; [int babel-interface-seqno;] [int babel-interface-hello-interval;] [int babel-interface-update-interval;] boolean babel-request-trigger-ack; boolean babel-lossy-link; [int babel-external-cost;] babel-neighbors-obj babel-neighbors<1..*>; [babel-security-obj babel-security<1..*>;] }babel-interfaces-obj; babel-interface-reference: reference to an interface object as defined by the data model babel-interface-seqno: the current sequence number in use for this interface babel-interface-hello-interval: the current hello interval in use for this interface babel-interface-update-interval: the current update interval in use for this interface babel-request-trigger-ack: requests acknowledgement of triggered updates (if number of neighbors less than babel-ack-limit); MAY be configurable babel-lossy-link: indicates (if true) that the link of this interface is considered lossy; MAY be configurable babel-external-cost: external input to cost of link of this interface (need to determine how to express this);MUST be configurable if implemented Stark Expires July 6, 2018 [Page 5] Internet-Draft Babel Information Model January 2018 2.4. Definition of babel-neighbors object { ip-address babel-neighbor-address; string babel-hello-history; int babel-txcost; int babel-hello-seqno; int babel-neighbor-ihu-interval; [int babel-rxcost] }babel-neighbors-obj; babel-neighbor-address: (IPv4 or v6) address the neighbor sends messages from babel-hello-history: the Hello history (do we want a human readable format?) babel-txcost: transmission cost value from the last IHU packet received from this neighbor, or meximum value (infinity) to indicates the IHU hold timer for this neighbor has expired babel-hello-seqno: expected Hello sequence number babel-neighbor-ihu-interval: current IHU interval for this neighbor babel-router-id: router-id of the neighbor babel-rxcost: reception cost calculated for this neighbor 2.5. Definition of babel-security object { string babel-security-supported; string babel-security-enabled-protocol; credentials babel-security-self-cred; babel-trust-obj babel-trust<1..*>; }babel-security-obj; babel-security-supported: list of supported security mechanisms babel-security-enabled-protocol: the currently enabled security protocol; empty if none is enabled babel-security-self-cred: the credentials this router presents to participate in the enabled security protocol Stark Expires July 6, 2018 [Page 6] Internet-Draft Babel Information Model January 2018 babel-trust-obj: a set of babel-trust objects that identify the credentials of a router whose babel messages are trusted 2.6. Definition of babel-trust object { credentials babel-trust-cred; }babel-trust-obj; babel-trust-cred: the credentials of a router whose babel messages can be trusted 2.7. Definition of babel-sources object { ip-address babel-source-prefix; int babel-source-prefix-length; base64 babel-source-router-id; int babel-source-seqno; int babel-source-metric; [int babel-source-garbage-collection-time;] }babel-sources-obj; babel-source-prefix: Prefix this entry applies to babel-source-prefix-length: Length of the source prefix babel-source-router-id: router-id of the router originating this prefix babel-source-seqno: last sequence number used by this source babel-source-metric: this source's feasibility distance babel-source-garbage-collection-time: garbage-collection timer for this source 2.8. Definition of babel-routes Stark Expires July 6, 2018 [Page 7] Internet-Draft Babel Information Model January 2018 object { ip-address babel-route-prefix; int babel-route-prefix-length; base64 babel-route-router-id; base64 babel-route-neighbor; int babel-route-metric; int babel-route-seqno; ip-address babel-route-next-hop; boolean babel-route-selected; }babel-routes-obj; babel-route-prefix: Prefix (expressed in IP address format) for which this route is advertised babel-route-prefix-length: Length of the prefix for which this route is advertised babel-route-router-id: router-id of the source router for which this route is advertised babel-route-neighbor: neighbor that advertised this route (a router-id) babel-route-metric: the metric with which this route was advertised by the neighbor, or maximum value (infinity) to indicate a recently retracted route babel-route-seqno: the sequence number with which this route was advertised babel-route-next-hop: the next-hop address of this route babel-route-selected: a boolean flag indicating whether this route is selected, i.e., whether it is currently being used for forwarding and is being advertised 3. Acknowledgements Juliusz Chroboczek review has been very helpful in refining this information model. The language in the Notation section was mostly taken from RFC 8193 [RFC8193]. Stark Expires July 6, 2018 [Page 8] Internet-Draft Babel Information Model January 2018 4. References 4.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, March 1997, . [RFC6126bis] Chroboczek, J., "The Babel Routing Protocol", Work in Progress, draft-ietf-babel-rfc6126bis, October 2017. 4.2. Informative References [ISO.10646] International Organization for Standardization, "Information Technology - Universal Multiple-Octet Coded Character Set (UCS)", ISO Standard 10646:2014, 2014. [RFC3339] Klyne, G. and C. Newman, "Date and Time on the Internet: Timestamps", RFC 3339, DOI 10.17487/RFC3339, July 2002, . [RFC3986] Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform Resource Identifier (URI): Generic Syntax", STD 66, RFC 3986, DOI 10.17487/RFC3986, January 2005, . [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, . [RFC7298] Ovsienko, D., "Babel Hashed Message Authentication Code (HMAC) Cryptographic Authentication", RFC 7298, DOI 10.17487/RFC7298, July 2014, . [RFC8193] Burbridge, T., Eardley, P., Bagnulo, M., and J. Schoenwaelder, "Information Model for Large-Scale Measurement Platforms (LMAPs)", RFC 8193, DOI 10.17487/RFC8193, August 2017, . Stark Expires July 6, 2018 [Page 9] Internet-Draft Babel Information Model January 2018 Appendix A. Open Issues This draft must be reviewed against draft-ietf-babel-rfc6126bis. Following are some issues where a conscious decision may be useful: Closed by defining base64 type and using it for all router IDs: "babel-self-router-id: Should this be an opaque 64-bit value instead of int?" babel-interfaces-obj: "This needs further discussion, I fear some of these are implementation details." Would it be useful to define some parameters for reporting statistics or logs? [Yes, but these need to be proposed.] Would it be useful to define some parameters specifically for security anomalies? [Yes, but these need to be proposed.] I created a basic security model. It's useful for single (or no) active security mechanism; but not multiple active. OK? Do we need a registry for the supported security mechanisms? Author's Address Barbara Stark AT&T Atlanta, GA US Email: barbara.stark@att.com Stark Expires July 6, 2018 [Page 10]