Internet-Draft New TCP and IPv6 EH IPFIX IEs February 2023
Boucadair & Claise Expires 11 August 2023 [Page]
Workgroup:
OPSAWG
Internet-Draft:
draft-boucadair-opsawg-ipfix-tcpo-v6eh-00
Published:
Intended Status:
Standards Track
Expires:
Authors:
M. Boucadair
Orange
B. Claise
Huawei

Extended TCP Options and IPv6 Extension Headers IPFIX Information Elements

Abstract

This document sepcifies new IPFIX Information Elements (IEs) to solve some issues with existing ipv6ExtensionHeaders and tcpOptions IEs, especially the ability to export any observed TCP option or IPv6 Extension Headers.

Discussion Venues

This note is to be removed before publishing as an RFC.

Discussion of this document takes place on the Operations and Management Area Working Group Working Group mailing list (opsawg@ietf.org), which is archived at https://mailarchive.ietf.org/arch/browse/opsawg/.

Source for this draft and an issue tracker can be found at https://github.com/boucadair/ipfix-tcpoptions-and-v6eh.

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 11 August 2023.

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Table of Contents

1. Introduction

The current specification of ipv6ExtensionHeaders Information Element (IE) does not:

Alos, only TCP options having a kind =< 63 can be included in a tcpOptions IE. The specification of the tcpOptions IE does not describe how any observed TCP option in a packet can be exported using IPFIX. Also, there is no way to report the observed Experimental Identifiers (ExIDs) that are carried in shared TCP options (kind=253 or 254) [RFC6994].

This document specifies new IPFIX Information Elements to solve the abovementioned issues.

2. Conventions and Definitions

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 IPFIX-specific terminology (Information Element, Template, Collector, Data Record, Flow Record, Exporting Process, Collecting Process, etc.) defined in Section 2 of [RFC7011]. As in [RFC7011], these IPFIX-specific terms have the first letter of a word capitalized.

2.1. ipv6ExtensionHeadersFull Information Element

This document requests IANA to add this new IE to the IPFIX regisry:

  • Name: ipv6ExtensionHeadersFull
  • ElementID: TBD1

  • Description: IPv6 extension headers observed in packets of this Flow. The information is encoded in a set of bit fields. For each IPv6 option header, there is a bit in this set. The bit is set to 1 if any observed packet of this Flow contains the corresponding IPv6 extension header. Otherwise, if no observed packet of this Flow contained the respective IPv6 extension header, the value of the corresponding bit is 0. The IPv6 EH associated with each bit is provided in [NEW_IPFIX_IPv6EH_SUBREGISTRY].

    The value can be encoded in fewer octets as per the guidelines in Section 6.2 of [RFC7011].

  • Abstract Data Type: unsigned
  • Data Type Semantics: flags
  • Reference: [This-Document]
  • Additional Information: See the assigned bits to each IPv6 extension header in [NEW_IPFIX_IPv6EH_SUBREGISTRY]. See [RFC8200] for the general definition of IPv6 extension headers and [IPv6-EH] for assigned extension headers.

2.2. TCP Options

2.2.1. New Information Elements for the Full TCP Options Range: tcpOptionsFull

This document requests IANA to add this new IE to the IPFIX regisry:

  • Name: tcpOptionsFull
  • ElementID: TBD2

  • Description: TCP options in packets of this Flow. The information is encoded in a set of bit fields. For each TCP option, there is a bit in this set. The bit is set to 1 if any observed packet of this Flow contains the corresponding TCP option. Otherwise, if no observed packet of this Flow contained the respective TCP option, the value of the corresponding bit is 0.

    Options are mapped to bits according to their option numbers. Option number X is mapped to bit X. TCP option numbers are maintained by IANA.

    The value can be encoded in fewer octets as per the guidelines in Section 6.2 of [RFC7011].

  • Abstract Data Type: unsigned
  • Data Type Semantics: flags
  • Reference: [This-Document]
  • Additional Information: See the assigned TCP option kinds at [IANA-TCP]. See [RFC9293] for the general definition of TCP options.

2.2.2. New Information Elements for Shared TCP Options

ExIDs can be either 2 or 4 bytes in length [RFC6994]. Two new IEs are defined to accomodate these two lengths without introducing extra complexity in mixing both types in the same IE.

This document requests IANA to add the following new IEs to the IANA IPFIX registry [IANA-IPFIX].

2.2.2.1. tcpExID16 Information Element
  • Name: tcpExID16
  • ElementID: TBD3
  • Description: Observed 2-byte Expermients IDs (ExIDs) in a shared TCP option (Kind=253 or 254). The information is encoded in a set of 16-bit fields. Each 16-bit field carries the observed 2-byte ExID in a shared option.
  • Abstract Data Type: octetArray
  • Data Type Semantics: identifier
  • Additional Information: See assigned 16-bit ExIDs at [IANA-TCP-EXIDs].
  • Reference: [This-Document]
2.2.2.2. New IE: tcpExID32
  • Name: tcpExID32
  • ElementID: TBD4
  • Description: Observed 4-byte Expermients ID (ExIDs) in a shared TCP option (Kind=253 or 254). The information is encoded in a set of 16-bit fields. Each 32-bit field carries the observed 4-byte ExID in a shared option.
  • Abstract Data Type: octetArray
  • Data Type Semantics: identifier
  • Additional Information: See assigned 32-bit ExIDs at [IANA-TCP-EXIDs].
  • Reference: [This-Document]

3. Security Considerations

IPFIX security considerations are discussed in Section 8 of [RFC7012].

4. IANA Considerations

A set of requested IANA actions are described in the main document. These actions are not repeated here.

5. Normative References

[IANA-IPFIX]
IANA, "IP Flow Information Export (IPFIX) Entities", <https://www.iana.org/assignments/ipfix/ipfix.xhtml>.
[IANA-TCP]
IANA, "Transmission Control Protocol (TCP) Parameters, TCP Option Kind Numbers", <https://www.iana.org/assignments/tcp-parameters/tcp-parameters.xhtml#tcp-parameters-1>.
[IANA-TCP-EXIDs]
IANA, "Transmission Control Protocol (TCP) Parameters, TCP Experimental Option Experiment Identifiers (TCP ExIDs)", <https://www.iana.org/assignments/tcp-parameters/tcp-parameters.xhtml#tcp-exids>.
[IPv6-EH]
IANA, "Internet Protocol Version 6 (IPv6) Parameters, IPv6 Extension Header Types", <https://www.iana.org/assignments/ipv6-parameters/ipv6-parameters.xhtml#ipv6-parameters-1>.
[RFC2119]
Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, DOI 10.17487/RFC2119, , <https://www.rfc-editor.org/rfc/rfc2119>.
[RFC6994]
Touch, J., "Shared Use of Experimental TCP Options", RFC 6994, DOI 10.17487/RFC6994, , <https://www.rfc-editor.org/rfc/rfc6994>.
[RFC7011]
Claise, B., Ed., Trammell, B., Ed., and P. Aitken, "Specification of the IP Flow Information Export (IPFIX) Protocol for the Exchange of Flow Information", STD 77, RFC 7011, DOI 10.17487/RFC7011, , <https://www.rfc-editor.org/rfc/rfc7011>.
[RFC7012]
Claise, B., Ed. and B. Trammell, Ed., "Information Model for IP Flow Information Export (IPFIX)", RFC 7012, DOI 10.17487/RFC7012, , <https://www.rfc-editor.org/rfc/rfc7012>.
[RFC8174]
Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, , <https://www.rfc-editor.org/rfc/rfc8174>.
[RFC9293]
Eddy, W., Ed., "Transmission Control Protocol (TCP)", STD 7, RFC 9293, DOI 10.17487/RFC9293, , <https://www.rfc-editor.org/rfc/rfc9293>.

Acknowledgments

Thanks to Paul Aitken for the review.

Authors' Addresses

Mohamed Boucadair
Orange
Benoit Claise
Huawei