Internet-Draft ICMPv6 Ping Enabled IOAM Capabilities October 2021
Min & Mirsky Expires 27 April 2022 [Page]
Workgroup:
6MAN Working Group
Internet-Draft:
draft-xiao-6man-icmpv6-ioam-conf-state-00
Updates:
4884 (if approved)
Published:
Intended Status:
Standards Track
Expires:
Authors:
X. Min
ZTE Corp.
G. Mirsky
Ericsson

ICMPv6 Echo Request/Reply for Enabled In-situ OAM Capabilities

Abstract

This document describes the ICMPv6 IOAM Echo functionality, which uses the ICMPv6 IOAM Echo Request/Reply messages, allowing the IOAM encapsulating node to discover the enabled IOAM capabilities of each IOAM transit node and IOAM decapsulating node.

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 27 April 2022.

Table of Contents

1. Introduction

IPv6 encapsulation for In-situ OAM (IOAM) data is defined in [I-D.ietf-ippm-ioam-ipv6-options], which uses IPv6 hop-by-hop options and/or destination options to carry IOAM data.

As specified in [I-D.ietf-ippm-ioam-conf-state], echo request/reply can be used for the IOAM encapsulating node to discover the enabled IOAM capabilities at IOAM transit nodes and IOAM decapsulating node.

As specified in [RFC4443], the Internet Control Message Protocol for IPv6 (ICMPv6) is an integral part of IPv6, and the base protocol MUST be fully implemented by every IPv6 node. ICMPv6 messages include error messages and informational messages, and the latter are referred to as ICMPv6 Echo Request/Reply messages. [RFC4884] defines ICMPv6 Extension Structure by which multi-part ICMPv6 error messages are supported. [RFC8335] defines ICMPv6 Extended Echo Request/Reply messages, and the ICMPv6 Extended Echo Request contains an ICMPv6 Extension Structure customized for this message. Both [RFC4884] and [RFC8335] provide sound principles and examples on how to extend ICMPv6 error messages and echo request/reply messages.

This document describes the ICMPv6 IOAM Echo functionality, which uses the ICMPv6 IOAM Echo Request/Reply messages, allowing the IOAM encapsulating node to discover the enabled IOAM capabilities of each IOAM transit node and IOAM decapsulating node.

The IOAM encapsulating node sends an ICMPv6 IOAM Echo Request message to each IOAM transit and decapsulating node, then each receiving node executes access control procedures, and if access is granted, each receiving node returns an ICMPv6 IOAM Echo Reply message which indicates the enabled IOAM capabilities of the receiving node. The ICMPv6 IOAM Echo Reply contains an ICMPv6 Extension Structure exactly customized to this message, and the ICMPv6 Extension Structure contains one or more IOAM Capabilities Objects.

Note that before the IOAM encapsulating node sends the ICMPv6 IOAM Echo Request messages, it needs to know the IPv6 address of each node along the transport path of a data packet. that can be achieved by executing ICMPv6 traceroute or provisioning explicit path at the IOAM encapsulating node.

2. Conventions Used in This Document

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.

3. ICMPv6 IOAM Echo Request

The ICMPv6 IOAM Echo Request message is encapsulated in an IPv6 header [RFC8200], like any ICMPv6 message.

The ICMPv6 IOAM Echo Request message has the following format:

 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|     Type      |     Code      |          Checksum             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Identifier          |Sequence Number| Num of NS-IDs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
.           IOAM Capabilities Query Container Payload           .
.                        as specified in                        .
.         Section 3.1 of draft-ietf-ippm-ioam-conf-state        .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 1: ICMPv6 IOAM Echo Request Message

IPv6 Header fields:

ICMPv6 fields:

4. ICMPv6 IOAM Echo Reply

The ICMPv6 IOAM Echo Reply message is encapsulated in an IPv6 header [RFC8200], like any ICMPv6 message.

The ICMPv6 IOAM Echo Reply message has the following format:

 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|     Type      |     Code      |          Checksum             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Identifier          |Sequence Number| Num of NS-IDs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
.         IOAM Capabilities Response Container Payload          .
.                        as specified in                        .
.         Section 3.2 of draft-ietf-ippm-ioam-conf-state        .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 2: ICMPv6 IOAM Echo Reply Message

IPv6 Header fields:

ICMPv6 fields:

4.1. IOAM Capabilities Objects

All ICMPv6 IOAM Capabilities Objects are encapsulated in an ICMPv6 IOAM Echo Reply message.

Each ICMPv6 IOAM Capabilities Object has the following format:

 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|             Length            |   Class-Num   |   C-Type      |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
.                IOAM Capabilities Object Payload               .
.                        as specified in                        .
.        Section 3.2.x of draft-ietf-ippm-ioam-conf-state       .
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
Figure 3: IOAM Capabilities Object

Object fields:

  • Class-Num: IOAM Capabilities Objects. The values are listed as the following:
   Value         Object Name
   -----         -----------
   TBD3          IOAM Tracing Capabilities Object
   TBD4          IOAM Proof-of-Transit Capabilities Object
   TBD5          IOAM Edge-to-Edge Capabilities Object
   TBD6          IOAM DEX Capabilities Object
   TBD7          IOAM End-of-Domain Object
  • C-Type: Values are listed as the following:
   Class-Num     C-Type     C-Type Name
   ---------     ------     -----------
   TBD3          0          Reserved
                 1          Pre-allocated Tracing
                 2          Incremental Tracing
   TBD4          0          Reserved
   TBD5          0          Reserved
   TBD6          0          Reserved
   TBD7          0          Reserved
  • Length: Length of the object, measured in octets, including the Object Header and Object Payload.
  • Following the IOAM Capabilities Object Header, it's the IOAM Capabilities Object Payload, which is defined respectively in Section 3.2.1, Section 3.2.2, Section 3.2.3, Section 3.2.4, Section 3.2.5 and Section 3.2.6 of [I-D.ietf-ippm-ioam-conf-state].

4.2. Examples of IOAM Echo Reply

The format of ICMPv6 IOAM Echo Reply can vary from deployment to deployment.

In a deployment where only the default Namespace-ID is used, the IOAM Pre-allocated Tracing Capabilities and IOAM Proof-of-Transit Capabilities are enabled at the IOAM transit node that received ICMPv6 IOAM Echo Request message, the ICMPv6 IOAM Echo Reply message is depicted as the following:

 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|     Type      |     Code      |          Checksum             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Identifier          |Sequence Number| Num of NS-IDs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|             Length            |   Class-Num   |   C-Type      |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|               IOAM-Trace-Type                 |  Reserved   |W|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|         Namespace-ID          |          Egress_MTU           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|  Egress_if_id (short or wide format)         ......           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|             Length            |   Class-Num   |   C-Type      |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|         Namespace-ID          | IOAM-POT-Type |P|SoR|Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

In a deployment where only the default Namespace-ID is used, the IOAM Pre-allocated Tracing Capabilities, IOAM Proof-of-Transit Capabilities and IOAM Edge-to-Edge Capabilities are enabled at the IOAM decapsulating node that received ICMPv6 IOAM Echo Request message, the ICMPv6 IOAM Echo Reply message is depicted as the following:

 0                   1                   2                   3
 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|     Type      |     Code      |          Checksum             |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|           Identifier          |Sequence Number| Num of NS-IDs |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|             Length            |   Class-Num   |   C-Type      |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|               IOAM-Trace-Type                 |  Reserved   |W|
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|         Namespace-ID          |          Egress_MTU           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|  Egress_if_id (short or wide format)         ......           |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|             Length            |   Class-Num   |   C-Type      |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|         Namespace-ID          | IOAM-POT-Type |P|SoR|Reserved |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|             Length            |   Class-Num   |   C-Type      |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|         Namespace-ID          |         IOAM-E2E-Type         |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
|TSF|TSL|       Reserved        |              MBZ              |
+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

Note that when an ICMPv6 IOAM Echo Request message or IOAM Echo Reply message is received, the Payload Length field of IPv6 Header [RFC8200] indicates the message length.

5. ICMPv6 Message Processing

When a node receives an ICMPv6 IOAM Echo Request message and any of the following conditions apply, the node MUST silently discard the incoming message:

Otherwise, when a node receives an ICMPv6 IOAM Echo Request, it MUST format an ICMPv6 IOAM Echo Reply as follows:

5.1. Code Field Processing

The Code field MUST be set to (1) Malformed Query if any of the following conditions apply:

  • The ICMPv6 IOAM Echo Request does not include any Namespace-ID.
  • The value of Num of NS-IDs field does not match the contained list of Namespace-IDs.
  • The query is otherwise malformed.

The Code field MUST be set to (2) No Matched Namespace-ID if none of the contained list of Namespace-IDs is recognized.

The Code field MUST be set to (3) Exceed the minimum IPv6 MTU if the formatted ICMPv6 IOAM Echo Reply exceeds the minimum IPv6 MTU (i.e., 1280 octets). In this case, all objects MUST be stripped before forwarding the ICMPv6 Echo Reply to its destination.

Otherwise, the Code field MUST be set to (0) No Error.

6. Updates to RFC 4884

Section 4.6 of [RFC4884] provides a list of extensible ICMP messages (i.e., messages that can carry the ICMP Extension Structure). This document adds the ICMPv6 IOAM Echo Request message and the ICMPv6 IOAM Echo Reply message to that list.

7. IANA Considerations

This document requests the following IANA actions:

All codes mentioned above are assigned on an FCFS basis with a range of 0-255.

8. Security Considerations

Securiy issues discussed in [I-D.ietf-ippm-ioam-conf-state] apply to this document.

This document recommends using IP Authentication Header [RFC4302] or IP Encapsulating Security Payload Header [RFC4303] to provide integrity protection for IOAM Capabilities info.

This document recommends using IP Encapsulating Security Payload Header [RFC4303] to provide privacy protection for IOAM Capabilities info.

This document recommends that the network operators establish policies that restrict access to ICMPv6 IOAM Echo functionality. In order to enforce these policies, nodes that support ICMPv6 IOAM Echo functionality MUST support the following configuration options:

When a node receives an ICMPv6 IOAM Echo Request message that it is not configured to support, it MUST silently discard the message. See Section 5 for details.

In order to protect local resources, implementations SHOULD rate-limit incoming ICMPv6 IOAM Echo Request messages.

9. Acknowledgements

TBA.

10. References

10.1. Normative References

[I-D.ietf-ippm-ioam-conf-state]
Min, X., Mirsky, G., and L. Bo, "Echo Request/Reply for Enabled In-situ OAM Capabilities", Work in Progress, Internet-Draft, draft-ietf-ippm-ioam-conf-state-01, , <https://www.ietf.org/archive/id/draft-ietf-ippm-ioam-conf-state-01.txt>.
[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/info/rfc2119>.
[RFC4443]
Conta, A., Deering, S., and M. Gupta, Ed., "Internet Control Message Protocol (ICMPv6) for the Internet Protocol Version 6 (IPv6) Specification", STD 89, RFC 4443, DOI 10.17487/RFC4443, , <https://www.rfc-editor.org/info/rfc4443>.
[RFC4884]
Bonica, R., Gan, D., Tappan, D., and C. Pignataro, "Extended ICMP to Support Multi-Part Messages", RFC 4884, DOI 10.17487/RFC4884, , <https://www.rfc-editor.org/info/rfc4884>.
[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/info/rfc8174>.

10.2. Informative References

[I-D.ietf-ippm-ioam-ipv6-options]
Bhandari, S. and F. Brockners, "In-situ OAM IPv6 Options", Work in Progress, Internet-Draft, draft-ietf-ippm-ioam-ipv6-options-06, , <https://www.ietf.org/archive/id/draft-ietf-ippm-ioam-ipv6-options-06.txt>.
[RFC4302]
Kent, S., "IP Authentication Header", RFC 4302, DOI 10.17487/RFC4302, , <https://www.rfc-editor.org/info/rfc4302>.
[RFC4303]
Kent, S., "IP Encapsulating Security Payload (ESP)", RFC 4303, DOI 10.17487/RFC4303, , <https://www.rfc-editor.org/info/rfc4303>.
[RFC4594]
Babiarz, J., Chan, K., and F. Baker, "Configuration Guidelines for DiffServ Service Classes", RFC 4594, DOI 10.17487/RFC4594, , <https://www.rfc-editor.org/info/rfc4594>.
[RFC8200]
Deering, S. and R. Hinden, "Internet Protocol, Version 6 (IPv6) Specification", STD 86, RFC 8200, DOI 10.17487/RFC8200, , <https://www.rfc-editor.org/info/rfc8200>.
[RFC8335]
Bonica, R., Thomas, R., Linkova, J., Lenart, C., and M. Boucadair, "PROBE: A Utility for Probing Interfaces", RFC 8335, DOI 10.17487/RFC8335, , <https://www.rfc-editor.org/info/rfc8335>.

Authors' Addresses

Xiao Min
ZTE Corp.
Nanjing
China
Greg Mirsky
Ericsson
United States of America